Effect of Protein Kinase C on Endoplasmic Reticulum Cholesterol

Biochemical and Biophysical Research Communications. Jan, 2002  |  Pubmed ID: 11779197

Plasma membrane cholesterol both regulates and is regulated by effector proteins in the endoplasmic reticulum (ER) through a feedback system that is poorly understood. We now show that ER cholesterol varies over a fivefold range in response to experimental agents that act upon protein kinase C (PKC). Agents that activate Ca(2+)-dependent PKC [phorbol-12-myristate-13-acetate (PMA) and bryostatin 1] increased the level of ER cholesterol; inhibitors such as staurosporine and calphostin C decreased it. Rottlerin, a selective inhibitor of the PKC-delta isoform, also increased ER cholesterol. The esterification of plasma membrane cholesterol was altered by protein kinase C-directed agents in a corresponding fashion. Furthermore, the regulatory effect of plasma membrane cholesterol on the esterification of ER cholesterol was blocked by PKC-directed agents. These findings suggest that multiple protein kinase C isoforms participate in the regulation of ER cholesterol and therefore in cholesterol homeostasis.

Dynamics of Lysosomal Cholesterol in Niemann-Pick Type C and Normal Human Fibroblasts

Journal of Lipid Research. Feb, 2002  |  Pubmed ID: 11861661

The dynamics of endolysosomal cholesterol were investigated in Niemann-Pick type C (NPC) cells and in human fibroblasts treated with class 2 amphiphiles to mimic NPC cells. We showed through new approaches that the massive pools of endolysosomal cholesterol in these cells are not trapped but, rather, circulate to the cell surface at about the normal rate. This flux spared NPC and amphiphile-treated cells from disruption by the extraction of their plasma membrane cholesterol with cyclodextrin. Nocodazole, a microtubule-depolymerizing agent, reversed the resistance of NPC and U18666A-treated cells to cholesterol depletion, apparently by reducing the flux of endolysosomal cholesterol to the plasma membrane. Neither nocodazole nor bafilomycin A1 (an inhibitor of the vacuolar proton pump) acted in the same way as the NPC mutation or class 2 amphiphiles: both agents decreased plasma membrane cholesterol at the expense of the endolysosomal pool and both blocked the actions of the amphiphile, U18666A. Finally, the resistance of NPC cells to lysis by amphotericin B was shown not to reflect a reduction in plasma membrane cholesterol arising from a block in lysosomal cholesterol export but rather the diversion of the amphotericin B to cholesterol-rich endolysosomes. We conclude that the large pool of endolysosomal cholesterol in NPC and amphiphile-treated fibroblasts is dynamic and that its turnover, as in normal cells, is dependent on microtubules.

Fission Yeast Mutants Affecting Telomere Clustering and Meiosis-specific Spindle Pole Body Integrity

Genetics. Mar, 2002  |  Pubmed ID: 11901107

In meiotic prophase of many eukaryotic organisms, telomeres attach to the nuclear envelope and form a polarized configuration called the bouquet. Bouquet formation is hypothesized to facilitate homologous chromosome pairing. In fission yeast, bouquet formation and telomere clustering occurs in karyogamy and persists throughout the horsetail stage. Here we report the isolation and characterization of six mutants from our screen for meiotic mutants. These mutants show defective telomere clustering as demonstrated by mislocalization of Swi6::GFP, a heterochromatin-binding protein, and Taz1p::GFP, a telomere-specific protein. These mutants define four complementation groups and are named dot1 to dot4-defective organization of telomeres. dot3 and dot4 are allelic to mat1-Mm and mei4, respectively. Immunolocalization of Sad1, a protein associated with the spindle pole body (SPB), in dot mutants showed an elevated frequency of multiple Sad1-nuclei signals relative to wild type. Many of these Sad1 foci were colocalized with Taz1::GFP. Impaired SPB structure and function were further demonstrated by failure of spore wall formation in dot1, by multiple Pcp1::GFP signals (an SPB component) in dot2, and by abnormal microtubule organizations during meiosis in dot mutants. The coincidence of impaired SPB functions with defective telomere clustering suggests a link between the SPB and the telomere cluster.

Probing Red Cell Membrane Cholesterol Movement with Cyclodextrin

Biophysical Journal. Oct, 2002  |  Pubmed ID: 12324429

We probed the kinetics with which cholesterol moves across the human red cell bilayer and exits the membrane using methyl-beta-cyclodextrin as an acceptor. The fractional rate of cholesterol transfer (% s(-1)) was unprecedented, the half-time at 37 degrees C being ~1 s. The kinetics observed under typical conditions were independent of donor concentration and directly proportional to acceptor concentration. The rate of exit of membrane cholesterol fell hyperbolically to zero with increasing dilution. The energy of activation for cholesterol transfer was the same at high and low dilution; namely, 27-28 Kcal/mol. This behavior is not consistent with an exit pathway involving desorption followed by aqueous diffusion to acceptors nor with a simple one-step collision mechanism. Rather, it is that predicted for an activation-collision mechanism in which the reversible partial projection of cholesterol molecules out of the bilayer precedes their collisional capture by cyclodextrin. Because the entire membrane pool was transferred in a single first-order process under all conditions, we infer that the transbilayer diffusion (flip-flop) of cholesterol must have proceeded faster than its exit, i.e., with a half-time of <1 s at 37 degrees C.

Supragingival Calculus: Formation and Control

Critical Reviews in Oral Biology and Medicine : an Official Publication of the American Association of Oral Biologists. 2002  |  Pubmed ID: 12393761

Dental calculus is composed of inorganic components and organic matrix. Brushite, dicalcium phosphate dihydrate, octacalcium phosphate, hydroxyapatite, and whitlockite form the mineral part of dental calculus. Salivary proteins selectively adsorb on the tooth surface to form an acquired pellicle. It is followed by the adherence of various oral micro-organisms. Fimbriae, flagella, and some other surface proteins are essential for microbial adherence. Microbial co-aggregation and co-adhesion enable some micro-organisms, which are incapable of adhering, to adhere to the pellicle-coated tooth surface. Once organisms attach to the tooth surface, new genes could be expressed so that mature dental plaque can form and biofilm bacteria assume increased resistance to antimicrobial agents. Supersaturation of saliva and plaque fluid with respect to calcium phosphates is the driving force for plaque mineralization. Both salivary flow rate and plaque pH appear to influence the saturation degree of calcium phosphates. Acidic phospholipids and specific proteolipids present in cell membranes play a key role in microbial mineralization. The roles of crystal growth inhibitors, promoters, and organic acids in calculus formation are discussed. Application of biofilm culture systems in plaque mineralization is concisely reviewed. Anti-calculus agents used--centering on triclosan plus polyvinyl methyl ether/maleic acid copolymer, pyrophosphate plus polyvinyl methyl ether/maleic acid copolymer, and zinc ion-in commercial dentifrices are also discussed in this paper.

[A Clinical Study on Improving Phonation Function of Larynx After Partial Laryngectomy]

Lin Chuang Er Bi Yan Hou Ke Za Zhi = Journal of Clinical Otorhinolaryngology. Mar, 2003  |  Pubmed ID: 12815887

To analyse the clinical results of reconstruction of vocal cord using sternohyoid muscle flap after partial laryngectomy and research a new repairing method to improve laryngeal function and living quality of patient.

[The Expression of Vascular Endothelial Growth Factor and Its Receptor in Hematopoietic Malignant Cell Lines HL-60 and Raji]

Zhongguo Shi Yan Xue Ye Xue Za Zhi / Zhongguo Bing Li Sheng Li Xue Hui = Journal of Experimental Hematology / Chinese Association of Pathophysiology. Aug, 2003  |  Pubmed ID: 12962566

In order to explore the effect of vascular endothelial growth factor (VEGF) in hematological malignancies, the expression of VEGF and its receptor was detected in HL-60 and Raji cells by reverse transcriptase-polymerase chain reaction (RT-PCR), enzyme linked immunosorbent assay (ELISA) and immunohistochemistry. The results showed that VEGF-mRNA expressed in both HL-60 and Raji cells, and the mean VEGF concentrations in the cultural supernatant of both cell lines were significantly higher than that of normal peripheral blood mononuclear cell respectively. There was expression of VEGF-R (Flt-1) on the surfaces of both HL-60 and Raji cells. The research results demonstrated that VEGF-mRNA was expressed in hematopoietic malignant cell lines (HL-60 and Raji), and the corresponding protein was secreted into the extracellular microenvironment, the both cell lines expressed VEGF-R on the cell surface. VEGF affects not only vascular endothelial cells, but also leukemic and lymphoma cells themselves. It is suggested that an autocrine pathway of VEGF existed in the both cell lines other than the paracrine pathway. The autocrine pathway of VEGF works as basis of tumor invasion. In conclusion, to restrain expression of VEGF and its receptor may inhibit tumor growth, and helps to block the reciprocal loop between VEGF and endothelial cells, and decrease the tumor specialities of hyperproliferation, anti-apoptosis and invation, that may make the tumor more susceptible to chemotherapy.

Successful Resection of Enterovesical Fistula in a Patient with Sigmoid Colonic Malignancy

Chinese Medical Journal. Oct, 2003  |  Pubmed ID: 14640108

Genetic and Phenotypic Analysis of Alleles of the Drosophila Chromosomal JIL-1 Kinase Reveals a Functional Requirement at Multiple Developmental Stages

Genetics. Nov, 2003  |  Pubmed ID: 14668387

In this study we provide a cytological and genetic characterization of the JIL-1 locus in Drosophila. JIL-1 is an essential chromosomal tandem kinase and in JIL-1 null animals chromatin structure is severely perturbed. Using a range of JIL-1 hypomorphic mutations, we show that they form an allelic series. JIL-1 has a strong maternal effect and JIL-1 activity is required at all stages of development, including embryonic, larval, and pupal stages. Furthermore, we identified a new allele of JIL-1, JIL-1(h9), that encodes a truncated protein missing COOH-terminal sequences. Remarkably, the truncated JIL-1 protein can partially restore viability without rescuing the defects in polytene chromosome organization. This suggests that sequences within this region of JIL-1 play an important role in establishing and/or maintaining normal chromatin structure. By analyzing the effects of JIL-1 mutations we provide evidence that JIL-1 function is necessary for the normal progression of several developmental processes at different developmental stages such as oogenesis and segment specification. We propose that JIL-1 may exert such effects by a general regulation of chromatin structure affecting gene expression.

Disruption of Hepatitis C Virus RNA Replication Through Inhibition of Host Protein Geranylgeranylation

Proceedings of the National Academy of Sciences of the United States of America. Dec, 2003  |  Pubmed ID: 14668447

Hepatitis C virus (HCV) RNA replication depends on viral protein association with intracellular membranes, but the influence of membrane composition on viral replication is unclear. We report that HCV RNA replication and assembly of the viral replication complex require geranylgeranylation of one or more host proteins. In cultured hepatoma cells, HCV RNA replication was disrupted by treatment with lovastatin, an inhibitor of 3-hydroxy-3-methyglutaryl CoA reductase, or with an inhibitor of protein geranylgeranyl transferase I, each of which induced the dissolution of the HCV replication complex. Viral replication was not affected by treatment of cells with an inhibitor of farnesyl transferase. When added to lovastatin-treated cells, geranylgeraniol, but not farnesol, restored replication complex assembly and viral replication. Inasmuch as the HCV genome does not encode a canonical geranylgeranylated protein, the data suggest the involvement of a geranylgeranylated host protein in HCV replication. Inhibition of its geranylgeranylation affords a therapeutic strategy for treatment of HCV infection.

[Expression of Recombinant Plasmid PcDNA3.1/P12X3C with Multi-genes of Foot-and-mouth Disease Virus in BHK-21 Cells]

Sheng Wu Gong Cheng Xue Bao = Chinese Journal of Biotechnology. May, 2003  |  Pubmed ID: 15969026

In order to obtain the gene P12X3C of Foot-and-Mouth Disease Virus (FMDV) that includes full length P1, 2A, 3C and a part of 2B, the site mutation strategy was used. After being digested by Kpn I and Xba I respectively, the gene P12X3C was cloned into the pcDNA3.1 (+) expression vector. The recombinant plasmid was checked by restriction enzyme analysis and nucleic acid sequencing, and then named pcDNA3.1/P12X3C. Further, BHK-21 cells was transfected with pcDNA3.1/P12X3C by using lipoid. The proteins of Foot-and-Mouth Disease Virus, which were expressed in BHK-21 cells, were confirmed by sandwich-ELISA and fluoroscopy. The result shows the gene P12X3C is cloned into eukaryotic expression plasmid, and the recombinant eukaryotic expression plasmid pcDNA3.1/P12X3C could express proteins of Foot-and-Mouth Disease Virus in BHK-21 cells, which have immunocompetence. This study demonstrates that delivery of a recombinant eukaryotic expression plasmid containing P12X3C coding regions results in the assembly of FMDV capsid structures, which will offer experimental base to DNA vaccine of FMDV.

[The Effect of All-trans Retinoid Acid and Sodium Selenite (Na2SeO3) on VEGF and Its Receptor Expression in HL-60 Cells]

Zhongguo Shi Yan Xue Ye Xue Za Zhi / Zhongguo Bing Li Sheng Li Xue Hui = Journal of Experimental Hematology / Chinese Association of Pathophysiology. Apr, 2004  |  Pubmed ID: 15157320

In order to investigate the effect of non-medullar toxicity drug - all trans retinoid acid (ATRA) and cancer preventive trace element-selenium compound - sodium selenite (Na(2)SeO(3)) on the expression of vascular endothelial growth factor (VEGF) and its receptor in HL-60 cells, the expression of VEGF and its receptor in HL-60 cells were detected by ELISA technique and flow cytometry before and after treatment with two drugs. The results showed that the mean VEGF concentrations in the cultural supernatant of 5 and 10 micro mol/L ATRA-treated HL-60 cells for 48 and 72 hours were lower than those of the control group without adding ATRA. The differences between the ATRA-treated groups and the control group were statistically significant (P = 0.001, P = 0.000, P < 0.01, respectively). The levels of VEGF-R on the surface of HL-60 cells also decreased after treatment with ATRA of 5 and 10 micro mol/L for 72 hours, but at 48 hours the expression rates of VEGF-R on HL-60 cells of the two ATRA treated groups were not significantly decreased. At 48 and 72 hours, Na(2)SeO(3) of 5 and 10 micro mol/L had no obvious effect on HL-60 secreting VEGF, but notablely inhibited the expression of VEGF-R. In conclusion, ATRA could inhibit the expression of VEGF and its receptor in HL-60 cell. Na(2)SeO(3) could not inhibit the expression of VEGF in HL-60 cell, but could decrease the receptor expression of VEGF, which mechanism should be further studied. ATRA and Na(2)SeO(3) had not obvious medullar-inhibition, but anti-angiogenesis activity. It is suggested that combination of two drugs with conventional therapy may enhance the effect of radiotherapy and chemotherapy, and reduce the dose and thus toxicity of chemotherapeutic agents.

Endoscopic Band Ligation Without Electrosurgery: a New Technique for Excision of Small Upper-GI Leiomyoma

Gastrointestinal Endoscopy. Aug, 2004  |  Pubmed ID: 15278048

Leiomyoma is a relatively common submucosal tumor in the upper-GI tract. The efficacy of a new method for resection of these tumors, endoscopic band ligation, was evaluated.

How Cholesterol Homeostasis is Regulated by Plasma Membrane Cholesterol in Excess of Phospholipids

Proceedings of the National Academy of Sciences of the United States of America. Aug, 2004  |  Pubmed ID: 15289597

How do cells sense and control their cholesterol levels? Whereas most of the cell cholesterol is located in the plasma membrane, the effectors of its abundance are regulated by a small pool of cholesterol in the endoplasmic reticulum (ER). The size of the ER compartment responds rapidly and dramatically to small changes in plasma membrane cholesterol around the normal level. Consequently, increasing plasma membrane cholesterol in vivo from just below to just above the basal level evoked an acute (<2 h) and profound ( approximately 20-fold) decrease in ER 3-hydroxy-3-methylglutaryl-CoA reductase activity in vitro. We tested the hypothesis that the sharply inflected ER response to cholesterol is governed by the thermodynamic activity (fugacity) of plasma membrane cholesterol. The following two independent measures of plasma membrane cholesterol activity in human red cells and fibroblasts were used: susceptibility to cholesterol oxidase and cholesterol transfer to cyclodextrin. Both indicators revealed a threshold at the physiologic set point of plasma membrane cholesterol. Incrementing the phospholipid compartment in the plasma membrane with lysophosphatidylcholine, previously shown to decrease cholesterol oxidase susceptibility, reduced the transfer of plasma membrane cholesterol to cyclodextrin and to the ER. Conversely, the membrane intercalator, n-octanol, increased cholesterol oxidation, transfer, and ER pool size, perhaps by displacing cholesterol from plasma membrane phospholipids. We conclude that the activity of the fraction of cholesterol in excess of other plasma membrane lipids sets the cholesterol level in the ER. Cholesterol-sensitive elements therein respond by nulling the active plasma membrane pool, thereby keeping the cholesterol matched to the other plasma membrane lipids.

Proteolytic Activation of Sterol Regulatory Element-binding Protein Induced by Cellular Stress Through Depletion of Insig-1

The Journal of Biological Chemistry. Oct, 2004  |  Pubmed ID: 15304479

Insig-1 and Insig-2 are closely related proteins of the endoplasmic reticulum (ER) that block proteolytic activation of sterol regulatory element-binding proteins (SREBPs), membrane-bound transcription factors that activate synthesis of cholesterol and fatty acids in animal cells. When cellular cholesterol levels are high, Insig proteins bind to SREBP cleavage-activating protein, retaining it in the ER and preventing it from escorting SREBPs to the site of proteolytic activation in the Golgi complex. Here we report that hypotonic stress reverses the sterol-mediated inhibition of SREBP proteolytic activation by reducing the level of Insig-1 but not Insig-2. The reduction of Insig-1, a protein with a rapid turnover rate, results from a general inhibition of protein synthesis mediated by hypotonic stress. Insig-2 is not affected by hypotonic stress because of its slower turnover rate. Inhibition of protein synthesis by hypotonic shock has not been reported previously. Thapsigargin, an activator of the ER stress response, also inhibits protein synthesis and activates proteolysis of SREBP. Such activation also correlates with the disappearance of Insig-1. The current study demonstrates that animal cells, in response to either hypotonic shock or ER stress, can bypass the cholesterol inhibition of SREBP processing, an effect that is attributable to the rapid turnover of Insig-1.

Biofilm Formation of Candida Albicans is Variably Affected by Saliva and Dietary Sugars

Archives of Oral Biology. Oct, 2004  |  Pubmed ID: 15308423

The pathogenesis of both superficial and systemic candidiasis is closely dictated by properties of the yeast biofilms. Despite extensive investigations on bacterial biofilms, the characteristics of candidal biofilms, and various factors affecting this process remain to be determined. Therefore we examined the effect of human whole saliva and dietary sugars, glucose and galactose on the adhesion and biofilm formation of Candida albicans. Biofilms of C. albicans isolate 192 887 g were developed on polystyrene, flat-bottomed 96-well microtiter plates and monitored using ATP bioluminescence and tetrazolium (XTT) reduction assays as well as the conventional colony forming unit (CFU) evaluation. Our data showed that both the ATP and the XTT assays strongly correlated with the CFU assay (ATP versus CFU: r = 0.994, P = 0.006; XTT versus CFU: r = 0.985, P = 0.015). Compared with a glucose-supplemented (100 mM) medium, galactose containing (500 mM) medium generated consistently lower levels of both candidal adhesion and biofilm formation (all P < 0.05), but a higher pace of biofilm development over time (96 h). Whist the presence of an immobilised saliva coating had little effect on either the candidal adhesion or biofilm formation, the addition of saliva to the incubation medium quantitatively affected biofilm formation especially on day 3 and 4, without any significant effect on yeast adhesion. To conclude, biofilm formation of C. albicans within the oral milieu appears to be modulated to varying extents by dietary and salivary factors and, further investigations are required to elucidate these complex interactions.

[Computer Tomography Characteristics of Chronic Invasive Fungal Rhinosinusitis in Early Stage]

Lin Chuang Er Bi Yan Hou Ke Za Zhi = Journal of Clinical Otorhinolaryngology. May, 2004  |  Pubmed ID: 15311510

To discuss the computer tomography (CT) characteristics of chronic invasive fungal rhinosinusitis in early stage and their diagnostic value.

Spindle Pole Body Duplication in Fission Yeast Occurs at the G1/S Boundary but Maturation is Blocked Until Exit from S by an Event Downstream of Cdc10+

Molecular Biology of the Cell. Dec, 2004  |  Pubmed ID: 15385623

The regulation and timing of spindle pole body (SPB) duplication and maturation in fission yeast was examined by transmission electron microscopy. When cells are arrested at G1 by nitrogen starvation, the SPB is unduplicated. On release from G1, the SPBs were duplicated after 1-2 h. In cells arrested at S by hydroxyurea, SPBs are duplicated but not mature. In G1 arrest/release experiments with cdc2.33 cells at the restrictive temperature, SPBs remained single, whereas in cells at the permissive temperature, SPBs were duplicated. In cdc10 mutant cells, the SPBs seem not only to be duplicated but also to undergo partial maturation, including invagination of the nuclear envelope underneath the SPB. There may be an S-phase-specific inhibitor of SPB maturation whose expression is under control of cdc10(+). This model was examined by induction of overreplication of the genome by overexpression of rum1p or cdc18p. In cdc18p-overexpressing cells, the SPBs are duplicated but not mature, suggesting that cdc18p is one component of this feedback mechanism. In contrast, cells overexpressing rum1p have large, deformed SPBs accompanied by other features of maturation and duplication. We propose a feedback mechanism for maturation of the SPB that is coupled with exit from S to trigger morphological changes.

Hierarchical Planning for a Surface Mounting Machine Placement

Journal of Zhejiang University. Science. Nov, 2004  |  Pubmed ID: 15495340

For a surface mounting machine (SMM) in printed circuit board (PCB) assembly line, there are four problems, e.g. CAD data conversion, nozzle selection, feeder assignment and placement sequence determination. A hierarchical planning for them to maximize the throughput rate of an SMM is presented here. To minimize set-up time, a CAD data conversion system was first applied that could automatically generate the data for machine placement from CAD design data files. Then an effective nozzle selection approach implemented to minimize the time of nozzle changing. And then, to minimize picking time, an algorithm for feeder assignment was used to make picking multiple components simultaneously as much as possible. Finally, in order to shorten pick-and-place time, a heuristic algorithm was used to determine optimal component placement sequence according to the decided feeder positions. Experiments were conducted on a four head SMM. The experimental results were used to analyse the assembly line performance.

[Morphological Analysis of Acetabulum Bony Curved Surface]

Sheng Wu Yi Xue Gong Cheng Xue Za Zhi = Journal of Biomedical Engineering = Shengwu Yixue Gongchengxue Zazhi. Oct, 2004  |  Pubmed ID: 15553844

By using the reverse engineering (RE) technology, the mesh surface model of acetabulum was reconstructed by triangulation. Based on this kind of model, the local morphological analysis (LMA) and global morphological analysis (GMA) could be processed. The fitting minimal quadric surface method was applied to calculate the curvature of any point on the acetabulum bony surface, the local morphological character of its surface could be acquired, and its global surface character could be determined by GMA. The results showed that the acetabulum bony surface is elliptical surface, and its three eigenvalues (lambda1, lambda2, lambda3) relations on the three axes (x, y, z) are as follows: lambda1 is short than lambda2 and lambda3, lambda2 is close to lambda3.

[A Study on New Computer-aided Modeling Method of Hip Joint]

Sheng Wu Yi Xue Gong Cheng Xue Za Zhi = Journal of Biomedical Engineering = Shengwu Yixue Gongchengxue Zazhi. Oct, 2004  |  Pubmed ID: 15553868

The main reason of invalidation of prosthetic hip joint is the prostheses flexibility and shift, dislocation and disjunction. Promoting the long time stability of the prostheses is the key of improving the long term hip joint replacement effect. Former research work was focused on the upper segment of femur, and assumed the acetabulum cup to be a spheric concave, and the external form of acetabulum prostheses was basically semi spheric. This paper presents a method of acquiring the point data on the surface of the hip bone using the reverse engineering technology. By analyzing the acetabulum surface fitting error we use rotating elliptical surface to fit the acetabulum surface, together with the optimal technique to build up the CAD model of acetabulum surface. We compare the fitting error between the sphere fitting and rotating elliptical surface fitting and get the result that the rotating elliptical surface fitting error is smaller than the sphere fitting error, and the rotating elliptical surface can describe the shape of the acetabulum better.

Identification of FBL2 As a Geranylgeranylated Cellular Protein Required for Hepatitis C Virus RNA Replication

Molecular Cell. May, 2005  |  Pubmed ID: 15893726

We recently reported that Hepatitis C virus (HCV) RNA replication requires one or more geranylgeranylated host proteins. Using a combination of [(3)H]mevalonate labeling, coimmunoprecipitation, and bioinformatic search, we identified a geranylgeranylated host protein required for HCV RNA replication. This protein, FBL2, contains an F box domain and a CAAX motif (CVIL). It forms a stable immunoprecipitable complex with the HCV nonstructural protein 5A (NS5A). The association of FBL2 with NS5A requires the CAAX motif of FBL2, but not the F box. Deletion of the F box created a dominant-negative protein that inhibited replication of HCV RNA when overexpressed in Huh7-K2040 cells; this inhibition was overcome by coexpression of NS5A. siRNA-mediated knockdown of FBL2 mRNA by 70% in Huh7-HP cells reduced HCV RNA by 65%; this reduction was overcome by expression of a cDNA encoding a wobble mutant of FBL2. The current data indicate that geranylgeranylated FBL2 binds to NS5A in a reaction crucial for HCV RNA replication.

The Fission Yeast Homolog of the Human Transcription Factor EAP30 Blocks Meiotic Spindle Pole Body Amplification

Developmental Cell. Jul, 2005  |  Pubmed ID: 15992541

Centrosome aberrations caused by misregulated centrosome maturation result in defective spindle and genomic instability. Here we report that the fission yeast homolog of the human transcription factor EAP30, Dot2, negatively regulates meiotic spindle pole body (SPB, the yeast equivalent of centrosome) maturation. dot2 mutants show excess electron-dense material accumulating near SPBs, which we refer to as aberrant microtubule organization centers (AMtOCs). These AMtOCs assemble multipolar spindles, leading to chromosome missegregation. SPB aberrations were associated with elevated levels of Pcp1, the fission yeast ortholog of pericentrin/kentrin, and reducing pcp1(+) expression significantly suppressed AMtOCs in dot2-439 cells. Our findings, therefore, uncover meiosis-specific regulation of SPB maturation and provide evidence that a member of the conserved EAP30 family is required for maintenance of genome stability through regulation of SPB maturation. EAP30 is part of a transcription factor complex associated with acute myeloid leukemia, so these results may have relevance to human cancer.

[Effect of Puerarin on the Expression of Hsp70 in the Rats with Cerebral Injury Induced by Acute Local Ischemia]

Zhongguo Zhong Yao Za Zhi = Zhongguo Zhongyao Zazhi = China Journal of Chinese Materia Medica. Apr, 2005  |  Pubmed ID: 16011103

To study the effect of puerarin on the expression of Hsp (heat shock protein) 70 in the rats with cerebral injury induced by acute local ischemia.

[Study on Purification of Total Peony Glycoside with D140 Macroporous Resin]

Zhong Yao Cai = Zhongyaocai = Journal of Chinese Medicinal Materials. Mar, 2005  |  Pubmed ID: 16107028

To study the extraction process of total peony glycoside from Paeonia veitchii Lynvh.

Activation of Membrane Cholesterol by Displacement from Phospholipids

The Journal of Biological Chemistry. Oct, 2005  |  Pubmed ID: 16129675

We tested the hypothesis that certain membrane-intercalating agents increase the chemical activity of cholesterol by displacing it from its low activity association with phospholipids. Octanol, 1,2-dioctanoyl-sn-glycerol (a diglyceride), and N-hexanoyl-D-erythrosphingosine (a ceramide) were shown to increase both the rate of transfer and the extent of equilibrium partition of human red blood cell cholesterol to methyl-beta-cyclodextrin. These agents also promoted the interaction of the sterol with two cholesterol-specific probes, cholesterol oxidase and saponin. Expanding the pool of bilayer phospholipids with lysophosphatides countered these effects. The three intercalators also protected the red cells against lysis by cholesterol depletion as if substituting for the extracted sterol. As is the case for excess plasma membrane cholesterol, treating human fibroblasts with octanol, diglyceride, or ceramide stimulated the rapid inactivation of their hydroxymethylglutaryl-CoA reductase, presumably through an increase in the pool of endoplasmic reticulum cholesterol. These data supported the stated hypothesis and point to competition between cholesterol and endogenous and exogenous intercalators for association with membrane phospholipids. We also describe simple screens using red cells in a microtiter well format to identify intercalating agents that increase or decrease the activity of membrane cholesterol.

[Detection of Glucocorticoid Receptor-alpha MRNA Expression Using FQ-RT-PCR in Nasal Polyp]

Lin Chuang Er Bi Yan Hou Ke Za Zhi = Journal of Clinical Otorhinolaryngology. Sep, 2005  |  Pubmed ID: 16334247

To detect the expression of the glucocorticoid receptor-alpha (GR-alpha) mRNA in nasal polyp and normal nasal mucosa and investigate the significance of GR-alpha in progression of nasal polyp.

Down-regulation of Specific Gene Expression by Double-strand RNA Induces Neural Stem Cell Differentiation in Vitro

Molecular and Cellular Biochemistry. Jul, 2005  |  Pubmed ID: 16335801

In the postgenomic era the elucidation of the physiological function of genes has become the rate-limiting step in the quest to understand the development and function of living organisms. Double-stranded RNA (dsRNA) interferes with gene expression in various species, a phenomenon known as RNA interference (RNAi). We show here that RNAi is also effective in modifying gene expression in neural stem cell differentiation. The progenitor cells were obtained from E14 mouse embryonic forebrain and maintained using N-2 medium containing basic fibroblast growth factor (bFGF), epidermal growth factor (EGF) and B27.A gene (NM017084.1) was previously discovered and validated to express obviously differently between differentiated and undifferentiated neural stem cells in our laboratory. Here we report a long double-stranded RNA to knock out or knock down this gene. The results demonstrated that following RNAi inhibition of expression of the NM017084.1 gene, the differentiation of neural stem cells is accelerated. Thus the NM017084.1 gene may play a pivotal role in the process of differentiation of neural stem cells.

Sterol-regulated Ubiquitination and Degradation of Insig-1 Creates a Convergent Mechanism for Feedback Control of Cholesterol Synthesis and Uptake

Cell Metabolism. Jan, 2006  |  Pubmed ID: 16399501

This paper describes a convergent mechanism for the feedback control of cholesterol synthesis and uptake mediated by SREBPs, membrane bound transcription factors. Endoplasmic reticulum (ER) bound SREBPs form complexes with Scap, a polytopic ER protein. In sterol-overloaded cells, Scap/SREBP binds to Insig-1, which retains the complex in the ER. Upon sterol deprivation, the Scap/SREBP complex dissociates from Insig-1, which is then ubiquitinated on lysines 156 and 158 and degraded in proteasomes. Scap/SREBP moves to the Golgi, where SREBP is processed to liberate a nuclear fragment that activates genes for cholesterol synthesis and uptake and the gene for Insig-1. Ubiquitination is not necessary for release of Scap/SREBP from Insig-1, but it establishes a requirement for synthesis of new Insig-1 for feedback inhibition. When the new Insig-1 and cholesterol converge on Scap, Scap/SREBP binds to Insig-1, preventing ubiquitination. The Insig-1/Scap/SREBP complex accumulates in the ER, ready for liberation when the cell is again sterol deprived.

Proteasomal Degradation of Ubiquitinated Insig Proteins is Determined by Serine Residues Flanking Ubiquitinated Lysines

Proceedings of the National Academy of Sciences of the United States of America. Mar, 2006  |  Pubmed ID: 16549805

Insig-1 and Insig-2 are closely related proteins of the endoplasmic reticulum that play crucial roles in cholesterol homeostasis by inhibiting excessive cholesterol synthesis and uptake. In sterol-depleted cells Insig-1 is degraded at least 15 times more rapidly than Insig-2, owing to ubiquitination of Lys-156 and Lys-158 in Insig-1. In this study, we use domain-swapping methods to localize amino acid residues responsible for this differential degradation. In the case of Insig-2, Glu-214 stabilizes the protein by preventing ubiquitination. When Glu-214 is changed to alanine, Insig-2 becomes ubiquitinated, but it is still not degraded as rapidly as ubiquitinated Insig-1. The difference in the degradation rates is traced to two amino acids: Ser-149 in Insig-1 and Ser-106 in Insig-2. Ser-149, which lies NH(2)-terminal to the ubiquitination sites, accelerates the degradation of ubiquitinated Insig-1. Ser-106, which is COOH-terminal to the ubiquitination sites, retards the degradation of ubiquitinated Insig-2. The current studies indicate that the degradation of ubiquitinated Insigs is controlled by serine residues flanking the sites of ubiquitination.

Juxtamembranous Aspartic Acid in Insig-1 and Insig-2 is Required for Cholesterol Homeostasis

Proceedings of the National Academy of Sciences of the United States of America. Apr, 2006  |  Pubmed ID: 16606821

Insig-1 and Insig-2 are closely related proteins of the endoplasmic reticulum (ER) that mediate feedback control of cholesterol synthesis by sterol-dependent binding to the following two membrane proteins: the escort protein Scap, thus preventing proteolytic processing of sterol regulatory element-binding proteins; and the cholesterol biosynthetic enzyme 3-hydroxy-3-methylglutaryl CoA reductase, thus inducing the ubiquitination and ER-associated degradation of the enzyme. Here, we report that the conserved Asp-205 in Insig-1, which abuts the fourth transmembrane helix at the cytosolic side of the ER membrane, is essential for its dual function. When Asp-205 was mutated to alanine, the mutant Insig-1 lost the ability to bind to Scap and, thus, was unable to suppress the cleavage of sterol regulatory element-binding proteins. The mutant Insig-1 was ineffective also in accelerating sterol-stimulated degradation of 3-hydroxy-3-methylglutaryl CoA reductase. Alanine substitution of the corresponding aspartic acid in Insig-2 produced the same dual defects. These studies identify a single amino acid residue that is crucial for the function of Insig proteins in regulating cholesterol homeostasis in mammalian cells.

[Investigation of GR MRNA Quantu Expression in Chronic Sinusitis and Nasal Polyps]

Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi = Chinese Journal of Otorhinolaryngology Head and Neck Surgery. Mar, 2006  |  Pubmed ID: 16759008

To detect the expression of the glucocorticoid receptor-alpha/beta (GR-alpha/beta) mRNA in nasal polyp and normal nasal mucosa and investigate the significance of receptor-alpha/beta in GC-insensitive and GC-sensitive patients.

Bqt2p is Essential for Initiating Telomere Clustering Upon Pheromone Sensing in Fission Yeast

The Journal of Cell Biology. Jun, 2006  |  Pubmed ID: 16769823

The telomere bouquet, i.e., telomere clustering on the nuclear envelope (NE) during meiotic prophase, is thought to promote homologous chromosome pairing. Using a visual screen, we identified bqt2/im295, a mutant that disrupts telomere clustering in fission yeast. Bqt2p is required for linking telomeres to the meiotic spindle pole body (SPB) but not for attachment of telomeres or the SPB to the NE. Bqt2p is expressed upon pheromone sensing and colocalizes thereafter to Sad1p, an SPB protein. This localization only depends on Bqt1p, not on other identified proteins required for telomere clustering. Upon pheromone sensing, generation of Sad1p foci next to telomeres depends on Bqt2p. However, depletion of Bqt2p from the SPB is dispensable for dissolving the telomere bouquet at the end of meiotic prophase. Therefore, telomere bouquet formation requires Bqt2p as a linking component and is finely regulated during meiotic progression.

Sterol-regulated Degradation of Insig-1 Mediated by the Membrane-bound Ubiquitin Ligase Gp78

The Journal of Biological Chemistry. Dec, 2006  |  Pubmed ID: 17043353

Insig-1 and Insig-2, closely related endoplasmic reticulum membrane proteins, mediate transcriptional and post-transcriptional mechanisms that assure cholesterol homeostasis through their sterol-induced binding to Scap (SREBP cleavage-activating protein) and 3-hydroxy-3-methylglutaryl coenzyme A reductase. Recent studies show that Insig-1 (but not Insig-2) is ubiquitinated and rapidly degraded when cells are depleted of sterols. Conversely, ubiquitination of Insig-1 is blocked, and the protein is stabilized when intracellular sterols accumulate. Here, we report that the ubiquitin ligase gp78, which binds with much higher affinity to Insig-1 than Insig-2, is required for ubiquitination and degradation of Insig-1 in sterol-depleted cells. Sterols prevent Insig-1 ubiquitination and degradation by displacing gp78 from Insig-1, an event that results from sterol-induced binding of Scap to Insig-1. In addition to providing a mechanism for sterol-regulated degradation of Insig-1, these results help to explain why Scap is subject to endoplasmic reticulum retention upon Insig-1 binding, whereas 3-hydroxy-3-methylglutaryl coenzyme A reductase is ubiquitinated and degraded.

[Sleep Architecture Changes in Children with Adenoidal Hypertrophy]

Lin Chuang Er Bi Yan Hou Ke Za Zhi = Journal of Clinical Otorhinolaryngology. Dec, 2006  |  Pubmed ID: 17285975

Adenoidal hypertrophy in children is associated with obstructive manifestations like mouth breathing, snoring, night cough. However, the sleep architecture is poorly defined in children with AH, which is this studies for.

Analysis of Risk Factors for Hospital Mortality in Patients with Chronic Obstructive Pulmonary Diseases Requiring Invasive Mechanical Ventilation

Chinese Medical Journal. Feb, 2007  |  Pubmed ID: 17374279

Accurate prediction for prognosis is important for hospitalized patients with chronic obstructive pulmonary disease (COPD) requiring invasive mechanic ventilation (IMV) and for their family members to make end-of-life decisions. The response to therapy in such a patient population has rarely been investigated. The aim of the study was to evaluate the risk factors in these patients and investigate their response to IMV and the relationship between their responses and prognosis.

Hepatitis C Virus Production by Human Hepatocytes Dependent on Assembly and Secretion of Very Low-density Lipoproteins

Proceedings of the National Academy of Sciences of the United States of America. Apr, 2007  |  Pubmed ID: 17376867

Hepatitis C virus (HCV) and triglyceride-rich very low-density lipoproteins (VLDLs) both are secreted uniquely by hepatocytes and circulate in blood in a complex. Here, we isolated from human hepatoma cells the membrane vesicles in which HCV replicates. These vesicles, which contain the HCV replication complex, are highly enriched in proteins required for VLDL assembly, including apolipoprotein B (apoB), apoE, and microsomal triglyceride transfer protein. In hepatoma cells that constitutively produce infectious HCV, HCV production is reduced by two agents that block VLDL assembly: an inhibitor of microsomal triglyceride transfer protein and siRNA directed against apoB. These results provide a possible explanation for the restriction of HCV production to the liver and suggest new cellular targets for treatment of HCV infection.

[Impact of Adenotonsillectomy on Quality of Life in Children with Sleep Disordered Breathing]

Lin Chuang Er Bi Yan Hou Tou Jing Wai Ke Za Zhi = Journal of Clinical Otorhinolaryngology, Head, and Neck Surgery. Mar, 2007  |  Pubmed ID: 17511162

To compare improvement in quality of life after adenotonsillectomy in children with similar demographics but with either obstructive sleep apnea hypopnea syndrome (OSAHS) or with milder forms of sleep-disordered breathing (SDB). To evaluate the relationship between polysomnogram (PSG) results and disease-specific quality of life for children with obstructive sleep apnea 18 item survey (OSA-18).

[Transnasal Endoscopic Repair of Nasal-skull Base Defect: 69 Cases]

Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi = Chinese Journal of Otorhinolaryngology Head and Neck Surgery. May, 2007  |  Pubmed ID: 17629001

To summarize the experience of transnasal endoscopic repair of nasal-skull base defect.

[Up-regulation of MUC2 Mucin Gene in Chronic Rhinosinusitis]

Lin Chuang Er Bi Yan Hou Tou Jing Wai Ke Za Zhi = Journal of Clinical Otorhinolaryngology, Head, and Neck Surgery. Jun, 2007  |  Pubmed ID: 17674761

To investigate the expression of MUC2 in human sinus mucosa and compare the expression of MUC2 mRNAs in normal and in chronic sinus mucosa.

[Clinical Types, Diagnosis and Endoscopic Surgery of Choanal Polyps]

Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi = Chinese Journal of Otorhinolaryngology Head and Neck Surgery. Jun, 2007  |  Pubmed ID: 17702418

To investigate the clinical type, diagnosis and prognosis of endoscopic surgery of choanal polyp (CP).

[Correlation of Cyclooxygenase 2 with Upstream Mitogen-activated Protein Kinase, Nuclear Factor Kappa B Signal Transduction Pathway in Middle Turbinate Mucosa of Chronic Rhinosinusitis]

Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi = Chinese Journal of Otorhinolaryngology Head and Neck Surgery. Jun, 2007  |  Pubmed ID: 17702421

To detect the expression and correlation of cyclooxygenase 2 (COX-2)and key enzymes both of mitogen activated protein kinase (MAPK) and nuclear factor-kappa B( NF-KB) pathways in middle turbinate mucosa of chronic rhinosinusitis (CRS) and to investigate their roles in CRS pathogenesis.

Reliance of Host Cholesterol Metabolic Pathways for the Life Cycle of Hepatitis C Virus

PLoS Pathogens. Aug, 2007  |  Pubmed ID: 17784784

Hepatitis C virus (HCV), a single-stranded positive-sense RNA virus of the Flaviviridae family, infects more than 170 million people worldwide and is the leading cause of liver failure in the United States. A unique feature of HCV is that the viral life cycle depends on cholesterol metabolism in host cells. This review summarizes the cholesterol metabolic pathways that are required for the replication, secretion, and entry of HCV. The potential application of drugs that alter host cholesterol metabolism in treating HCV infection is also discussed.

Increased Serum Levels of C-reactive Protein and Matrix Metalloproteinase-9 in Obstructive Sleep Apnea Syndrome

Chinese Medical Journal. Sep, 2007  |  Pubmed ID: 17908454

Obstructive sleep apnea syndrome (OSAS), characterized by intermittent hypoxia/reoxygenation (IHR), has been identified as an independent risk factor for cardiovascular diseases (CVD). The CVD biomarkers associated with OSAS have not been thoroughly investigated.

HLA-A, -B, -DR Haplotype Frequencies from DNA Typing Data of 26,266 Chinese Bone Marrow Donors

Human Immunology. Oct, 2007  |  Pubmed ID: 17961775

HLA phenotypes of 26,266 Chinese individuals who were recruited as potential hematopoietic stem cell donors by the Shanghai Red Cross Marrow Donor Registry, part of the China Marrow Donor Program, were determined for HLA-A, -B, and -DRB1 alleles at low to intermediate resolution using DNA-based typing methods. The large sample size of the study allowed accurate calculation of the Chinese HLA haplotype frequencies. The observed alleles correspond to 19 HLA-A, 44 -B, and 13 -DR split antigens. The serologic equivalents of HLA-A36, -A80, -B78, and -DR18 alleles were not observed. A total of 2,241 distinct HLA-A, -B, -DRB1 haplotypes were identified. Three-locus haplotype frequency was estimated using the maximum likelihood method. The lowest haplotype frequency that can be reliably estimated at a 95% confidence level was 0.000057. Using this cutoff value, 1,220 haplotypes (54%) were statistically reliable and their cumulative haplotype frequency was 0.9730. The cumulative haplotype frequency of the remaining 1,021 haplotypes (46%) was 0.0270. A regression equation of p = 0.192 log N - 0.576 was derived to estimate the probability (p) of finding an HLA-A, -B, -DR split antigens-matched donor in a pool of N Chinese donors.

Determinants of Prolonged Mechanical Ventilation in Patients with Chronic Obstructive Pulmonary Diseases and Acute Hypercapnic Respiratory Failure

European Journal of Internal Medicine. Nov, 2007  |  Pubmed ID: 17967336

The aim of the present study was to identify early risk factors for prolonged mechanical ventilation (PMV) in chronic obstructive pulmonary disease (COPD) patients admitted to respiratory intensive care units (RICU) for acute hypercapnic respiratory failure.

[Eukaryonization of T7 RNA Polymerase Prokaryotic Expression System and Development of Its Couple Expression System]

Sheng Wu Gong Cheng Xue Bao = Chinese Journal of Biotechnology. Sep, 2007  |  Pubmed ID: 18051880

To make transcription of the target gene be driven by T7 RNA polymerase (T7 RNAP) in the eukaryotic cells, and the transcripts be CAP-independent translated. Firstly, the T7 RNAP was introduced into eukaryotic cells by two methods: (1) the BHK-21 cells were contransfected by the plasmid expressing T7 RNAP and pIERS-EGFP-ET vector; (2) by transfection of the cell line stably expressing T7 RNAP. The internal ribosome entry site (IRES) element from FMDV was cloned into the downstream of the T7 promoter sequence of the prokaryotic expressing vector pET-40a-c (+), resulted in the plasmid would express the transcripts carrying the IERS element at its 5' end. The enhanced green fluorescent protein (EGFP) gene was cloned into the downstream of the IERS element, resulted in plasmid pIERS-EGFP-ET. Then, the two kinds of cells expressing T7 RANP were transfected by pIERS-EGFP-ET. The green fluorescence in the transfected cells was observed under a fluorescence microscope equipped with a video documentation system. And the expressional efficiency was analyzed with flow cytometry (FCM). The results show that the IRES element from FMDV has the role of initiating CAP-independent translation, and lay foundation for researching function of the element and interrelated proteins. It would be potential for expressing target gene by the T7 RNAP couple expression system.

Detection of Abnormal Visual Cortex in Children with Amblyopia by Voxel-based Morphometry

American Journal of Ophthalmology. Mar, 2007  |  Pubmed ID: 17224120

To detect the abnormalities of gray matter in children with amblyopia by voxel-based morphometry (VBM).

Scrambling of Phospholipids Activates Red Cell Membrane Cholesterol

Biochemistry. Feb, 2007  |  Pubmed ID: 17269796

Cholesterol is predicted to associate more strongly with the outer than the inner leaflet of plasma membrane bilayers based on the relative in vitro affinities of their phospholipids. Complex formation with the high-affinity species (especially saturated sphingomyelins) is said to reduce the chemical activity (escape potential or fugacity) of the sterol. We therefore tested the hypothesis that scrambling the sidedness of plasma membrane phospholipids of intact cells will increase the chemical activity of outer surface cholesterol. Upon activating the plasma membrane scramblase in intact human red cells by introducing ionomycin to raise cytoplasmic Ca++, phosphatidylserine became exposed and, concomitantly, the chemical activity of exofacial cholesterol was increased. (This was gauged by its susceptibility to cholesterol oxidase and its rate of transfer to cyclodextrin.) Similar behavior was observed in human fibroblasts. Two other treatments known to activate cell surface cholesterol (namely, exposure to glutaraldehyde and to low-ionic-strength buffer) also brought phosphatidylserine to the cell surface but by a Ca++-independent mechanism. Given that phospholipid scrambling is important in blood coagulation and apoptosis, the concomitant activation of cell surface cholesterol could contribute to these and other pathophysiological signaling processes.

Underdevelopment of Optic Radiation in Children with Amblyopia: a Tractography Study

American Journal of Ophthalmology. Apr, 2007  |  Pubmed ID: 17276381

To detect the abnormalities of the optic radiation (OR) in children with amblyopia by diffusion tensor imaging (DTI) and tractography.

Inhibition of Hepatitis C Virus Replication by Peroxidation of Arachidonate and Restoration by Vitamin E

Proceedings of the National Academy of Sciences of the United States of America. Nov, 2007  |  Pubmed ID: 18003907

Hepatitis C virus (HCV) is a single-stranded positive-sense RNA virus of the Flaviviridae family. HCV-infected hepatocytes are known to produce reactive oxygen species (ROS), which initiate lipid peroxidation, a reaction that converts polyunsaturated fatty acids, such as arachidonate, into reactive carbonyls that inactivate proteins. To study the effect of lipid peroxidation on HCV replication, we administered arachidonate to Huh7 cells that harbor an HCV replicon (Huh7-K2040 cells). After incubation in medium supplemented with arachidonate but deprived of lipid-soluble antioxidants, the cellular amount of malondialdehyde (MDA), a product of lipid peroxidation, increased markedly in Huh7-K2040 cells but not in parental Huh7 cells that do not harbor an HCV replicon. This increase was followed by a sharp reduction (>95%) in HCV RNA. Both of these events were prevented when cells were treated with vitamin E, a lipid-soluble antioxidant. After prolonged incubation of Huh7-K2040 cells with arachidonate in the absence of lipid-soluble antioxidants, the amount of MDA decreased after the reduction in the amount of HCV RNA. Thus, in the presence of arachidonate and in the absence of lipid-soluble antioxidants, HCV replication induces lipid peroxidation that reduces the amount of HCV RNA. Our results provide a mechanism for the previous observation that polyunsaturated fatty acids inhibit HCV replication [Kapadia SB, Chisari FV (2005) Proc Natl Acad Sci USA 102:2561-2566], and they suggest that these agents may be effective in inhibiting HCV replication in vivo.

Effectors of Rapid Homeostatic Responses of Endoplasmic Reticulum Cholesterol and 3-hydroxy-3-methylglutaryl-CoA Reductase

The Journal of Biological Chemistry. Jan, 2008  |  Pubmed ID: 18024962

The cholesterol content of the endoplasmic reticulum (ER) and the activity of 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR) imbedded therein respond homeostatically within minutes to changes in the level of plasma membrane cholesterol. We have now examined the roles of sterol regulatory element-binding protein (SREBP)-dependent gene expression, side chain oxysterol biosynthesis, and cholesterol precursors in the short term regulation of ER cholesterol levels and HMGR activity. We found that SREBP-dependent gene expression is not required for the response to changes in cell cholesterol of either the pool of ER cholesterol or the rate of cholesterol esterification. It was also found that the acute proteolytic inactivation of HMGR triggered by cholesterol loading required the conversion of cholesterol to 27-hydroxycholesterol. High levels of exogenous 24,25-dihydrolanosterol drove the inactivation of HMGR; lanosterol did not. However, purging endogenous 24,25-dihydrolanosterol, lanosterol, and other biosynthetic sterol intermediates by treating cells with NB-598 did not greatly affect either the setting of their ER cholesterol pool or the inactivation of their HMGR. In summary, neither SREBP-regulated genes nor 27-hydroxycholesterol is involved in setting the ER cholesterol pool. On the other hand, 27-hydroxycholesterol, rather than cholesterol itself or biosynthetic precursors of cholesterol, stimulates the rapid inactivation of HMGR in response to high levels of cholesterol.

[Prevalence and Prognostic Factors for Postoperative Complications of Uvulopalatopharyngoplasty in Patients with Obstructive Sleep Apnea Hypopnea Syndrome]

Lin Chuang Er Bi Yan Hou Tou Jing Wai Ke Za Zhi = Journal of Clinical Otorhinolaryngology, Head, and Neck Surgery. May, 2008  |  Pubmed ID: 18652310

To explore the complication incidence and risk factors within immediate 24 hours after uvulopalatopharyngoplasty in patients with obstructive sleep apnea hypopnea syndrome (OSAHS) and provide theoretical foundation for preventing postoperative complication incidence.

[Effect of Lipopolysaccharide on Cyclooxygenase-2 Expression and Prostaglandin E2 Release in Human Nasal Epithelia]

Lin Chuang Er Bi Yan Hou Tou Jing Wai Ke Za Zhi = Journal of Clinical Otorhinolaryngology, Head, and Neck Surgery. Jun, 2008  |  Pubmed ID: 18727513

To detect cyclooxygenase-2 (COX-2) expression and prostaglandin E2 (PGE2) release in human nasal epithelia (HNE) induced by lipopolysaccharide (LPS) in different concentration gradient and time gradient, and to investigate their roles in nasal inflammatory pathogenesis.

[Apoptosis of Active T Lymphocytes Induced by Human Laryngocarcinoma Cell Line]

Lin Chuang Er Bi Yan Hou Tou Jing Wai Ke Za Zhi = Journal of Clinical Otorhinolaryngology, Head, and Neck Surgery. Jun, 2008  |  Pubmed ID: 18800686

To observe the expression of Fas receptor and ligand in human laryngocarcinoma cell line, Hep-2 and to investigate the possible mechanism of immune escape through Fas/FasL pathway in Hep-2 cell.

Unsaturated Fatty Acids Inhibit Proteasomal Degradation of Insig-1 at a Postubiquitination Step

The Journal of Biological Chemistry. Nov, 2008  |  Pubmed ID: 18835813

Proteasomes mediate the regulated degradation of Insig-1, a membrane protein of the endoplasmic reticulum (ER) that plays a crucial role in lipid metabolism. We showed previously that sterols inhibit this degradation by blocking ubiquitination of Insig-1. Here we show that unsaturated fatty acids stabilize Insig-1 without affecting its ubiquitination. Instead unsaturated fatty acids inhibit extraction of ubiquitinated Insig-1 from membranes, a process known to be mediated by valosin-containing protein and necessary for ER-associated degradation. Valosin-containing protein is recruited to Insig-1 through the action of another protein, Ubxd8. Unsaturated fatty acids block the binding between Ubxd8 and Insig-1, thereby abrogating the membrane extraction of Insig-1. Unsaturated fatty acid-mediated stabilization of Insig-1 enhances the ability of sterols to inhibit proteolytic activation of SREBP-1, which activates transcription of genes involved in fatty acid synthesis. The current study provides a molecular mechanism for regulation of proteasome-mediated ER protein degradation at a postubiquitination step.

[Effect of Beta-elemene on the Proliferation, Migration and RhoA Expression of Hepatic Stellate Cells Induced by Angiotensin II]

Zhonghua Gan Zang Bing Za Zhi = Zhonghua Ganzangbing Zazhi = Chinese Journal of Hepatology. Oct, 2008  |  Pubmed ID: 18983771

To explore the influence of beta-elemene on the proliferation, migration and RhoA expression of hepatic stellate cells (HSC) induced by angiotensin II (ANG II).

[Comparative Study of Two Primary Culture Methods of Human Nasal Epithelial Cells in Vitro]

Lin Chuang Er Bi Yan Hou Tou Jing Wai Ke Za Zhi = Journal of Clinical Otorhinolaryngology, Head, and Neck Surgery. Sep, 2008  |  Pubmed ID: 19086655

To compare two primary culture methods of human nasal epithelial (HNE) in vitro, and explore a suitable method to be used in further study.

[A Novel Red Phosphor (La3PO7:Eu3+) Prepared by Solid State Method]

Guang Pu Xue Yu Guang Pu Fen Xi = Guang Pu. Dec, 2008  |  Pubmed ID: 19248479

Novel red phosphor, Eu3+ -doped oxyphosphate (La3 PO7:Eu3+), was synthesized by a solid state method under high temperature. All the starting materials were analytical grade. La2O3, EuO3 and (NH4)2HPO4 weighed in appropriated molar ratios and ground in an agate mortar. Then the powder was treated under 1000 degrees C. The crystal phase of La3PO7:Eu3+ was investigated by X-ray diffraction (XRD) using a Cu target radiation resource (lamda = 1.54078 ?) and exhibited prominent peaks accordant with JCPDS standard card (33-0720) of La3PO7 in monoclinic phase. Emission and excitation spectra of La3PO7:Eu3+ were recorded at room temperature using a fluorescence spectrometer (Hitachi F-4500). Under 254 nm excitation, intense red fluorescence was observed from La3PO7:Eu3+, which was assigned to the (5)D0-->(7)F2 transition of Eu3+ ions. The intensity of the (5)D0-->(7)F2 transition is stronger than that of the (5)D0-->(7)F1 transition, showing that the Eu3+ ions were in the non-centrosym-metric sites in La3PO7. The CommissionIn-ternational DeL" Eclairage (CIE) coordinate of La3PO7:Eu3+ is (0.63,0.37) in the red area of CIE1931 XY chromaticity coordinate graph and close to that of Y2o3:Eu3+, but the cost of La3PO7 host is lower. This novel material may have potential applications in plasma display panels and Hg-free fluorescent lamps in the future.

Clinical Prognostic Factors of Chronic Rhinosinusitis After Endoscopic Sinus Surgery

ORL; Journal for Oto-rhino-laryngology and Its Related Specialties. 2008  |  Pubmed ID: 18408409

We aimed to determine the clinical prognostic factors of chronic rhinosinusitis after endoscopic sinus surgery (ESS) in order to better guide the management of patients.

Europium(III) Complexes/silica Hybrid Nanospheres Synthesized in Microemulsion

Journal of Nanoscience and Nanotechnology. Mar, 2008  |  Pubmed ID: 18468127

Eu(DBM)3Phen/silica nanospheres with a uniform diameter of approximately 40 nm and the characteristic fluorescence of Eu3+ ions have been synthesized by a microemulsion method. SEM and TEM analysis indicate that the hybrid nanospheres are core/shell structures with fine spherical surfaces and that Eu(DBM)3Phen has been successfully enveloped in the SiO2 spheres as chromophore cores. IR absorption spectra and photoluminescence spectra suggest that the hybrid nanoparticles are promising materials for bioassay.

A Novel Approach from Infrared to Ultraviolet Emission Enhancement in Yb3+, Er3+:CaF2 Nanofilms

Journal of Nanoscience and Nanotechnology. Mar, 2008  |  Pubmed ID: 18468135

Under 978 nm excitation, we explored the infrared-to-ultraviolet upconversion properties in the nanofilms with the nanoparticles of Yb3+, Er3+ codoped calcium fluoride (CaF2:Yb3+, Er3+). The strong enhancement of ultraviolet emission was observed. The result is attributed to the optical performance characteristics of the nanostructure materials. Furthermore, a novel upconversion approach explains well the UV-enhanced emission.

Multicolor Up-conversion Emissions of Tm3+/Er3+/Yb3+ Tri-doped YF3 Phosphors

Journal of Nanoscience and Nanotechnology. Mar, 2008  |  Pubmed ID: 18468159

Tm3+/Er3+/Yb3+ tri-doped yttrium fluoride (YF3) phosphors were prepared by a facile hydrothermal method. X-ray topographic analysis found that the phosphors were crystallized products. Their sizes and morphologies were characterized by scanning electron microscopy (SEM, Hitachi S-4800), which indicated that most of the YF3 phosphors were hundreds of nanometers in size. Up-conversion (UC) spectra were recorded under 980-nm diode laser excitation at room temperature with a fluorescence spectrometer (Hitachi F-4500). Plenty of UC emissions of Tm3+ and Er3+ were observed from ultraviolet to red. For Tm3+ ions, a five-photon process (approximately 291 nm and approximately 347 nm), a four-photon process (approximately 362 nm and approximately 452 nm), and a three-photon process (approximately 475 nm) were identified in the UC spectra. The UC emissions from the Er3+ were: approximately 380 nm, approximately 408 nm, approximately 521 nm, approximately 537 nm, and approximately 652 nm. Therefore, cyan-white light can be observed by the naked eye at 980-nm excitation, even under low excitation power density. By comparing the UC spectra of the phosphors annealed at different temperatures, we found that the intensity of the UC luminescence increased as annealing temperature increased. Furthermore, the spectral dependencies on Tm3+ doped concentrations were studied. The energy transfer processes and fluorescence dynamics in the tri-doped system are currently being investigated.

Self-assembly of Yb3+-Tm3+ Co-doped YF3 Elongated Nanocrystals into Nanobundles of Straw and Up-conversion Fluorescence

Journal of Nanoscience and Nanotechnology. Mar, 2008  |  Pubmed ID: 18468160

The hierarchical self-assembly of Yb3+ and Tm3+ co-doped YF3 elongated nanocrystals (NCs) into nanobundles of straw were synthesized through a facile hydrothermal route. The formational mechanisms of regular aggregates of the building blocks were studied. Ultraviolet (UV)-blue upconversion emissions of Tm3+ were recorded under 980-nm excitation by the Yb3+ sensitizer. The relatively bright blue emission indicated that the bundles have the potential for applications such as short-wavelength solid-state lasers and display devices.

Synthesis and Photophysical Properties of Core-shell Eu(DBM)3phen/TiO2 Nanohybrids

Journal of Nanoscience and Nanotechnology. Mar, 2008  |  Pubmed ID: 18468175

The core-shell titania (TiO2) hybrid spheres embedded with tris(dibenzoylmethanato)phenanthroline [Eu-(DBM)3phen] complex clusters were fabricated by a modified Stöber method. Under ultraviolet excitation (355 nm), the hybrid spheres exhibit the characteristic luminescence of the Eu3+ ions. The experimental results indicate that the titanic shell has different influences on the two fluorescent centers of Eu3+ ions. The emission from the centers on the complex surfaces was greatly enhanced when incorporated into titania spheres.

RNA Polymerase II-mediated Transcription at Active Loci Does Not Require Histone H3S10 Phosphorylation in Drosophila

Development (Cambridge, England). Sep, 2008  |  Pubmed ID: 18667461

JIL-1 is the major kinase controlling the phosphorylation state of histone H3S10 at interphase in Drosophila. In this study, we used three different commercially available histone H3S10 phosphorylation antibodies, as well as an acid-free polytene chromosome squash protocol that preserves the antigenicity of the histone H3S10 phospho-epitope, to examine the role of histone H3S10 phosphorylation in transcription under both heat shock and non-heat shock conditions. We show that there is no redistribution or upregulation of JIL-1 or histone H3S10 phosphorylation at transcriptionally active puffs in such polytene squash preparations after heat shock treatment. Furthermore, we provide evidence that heat shock-induced puffs in JIL-1 null mutant backgrounds are strongly labeled by antibody to the elongating form of RNA polymerase II (Pol IIoser2), indicating that Pol IIoser2 is actively involved in heat shock-induced transcription in the absence of histone H3S10 phosphorylation. This is supported by the finding that there is no change in the levels of Pol IIoser2 in JIL-1 null mutant backgrounds compared with wild type. mRNA from the six genes that encode the major heat shock protein in Drosophila, Hsp70, is transcribed at robust levels in JIL-1 null mutants, as directly demonstrated by qRT-PCR. Taken together, these data are inconsistent with the model that Pol II-dependent transcription at active loci requires JIL-1-mediated histone H3S10 phosphorylation, and instead support a model in which transcriptional defects in the absence of histone H3S10 phosphorylation are a result of structural alterations of chromatin.

Long Chain Acyl-CoA Synthetase 3-mediated Phosphatidylcholine Synthesis is Required for Assembly of Very Low Density Lipoproteins in Human Hepatoma Huh7 Cells

The Journal of Biological Chemistry. Jan, 2008  |  Pubmed ID: 18003621

Hepatocytes play a crucial role in regulating lipid metabolism by exporting cholesterol and triglyceride into plasma through secretion of very low density lipoproteins (VLDL). VLDL production is also required for release of hepatitis C virus (HCV) from infected hepatocytes. Here, we show that long chain acyl-CoA synthetase 3 (ACSL3) plays a crucial role in secretion of VLDL and HCV from hepatocytes. In cultured human hepatoma Huh7 cells, ACSL3 is specifically required for incorporation of fatty acids into phosphatidylcholine. In cells receiving small interfering RNA targeting ACSL3, secretion of apolipoprotein B, the major protein component of VLDL, was inhibited and the lipoprotein was rapidly degraded. This inhibition in secretion was completely eliminated when these cells were treated with phosphatidylcholine. Treatment of cells with small interfering RNA targeting ACSL3 also inhibited secretion of HCV from Huh7-derived cells. These results identify ACSL3 as a new enzymatic target to limit VLDL secretion and HCV infection.

Development of a Hamster Kidney Cell Line Expressing Stably T7 RNA Polymerase Using Retroviral Gene Transfer Technology for Efficient Rescue of Infectious Foot-and-mouth Disease Virus

Journal of Virological Methods. Mar, 2009  |  Pubmed ID: 19095010

Reverse genetics systems, with the ability to manipulate viral genomes at the DNA molecular level, are an important platform for study of the assembly and function of viruses. Genome manipulation, such as gene recombination, mosaicism, and mutation may interfere with replication, assembly and release of viruses. An efficient, convenient and economical method of virus rescue is undoubtedly required for increasing the efficiency of rescuing recombinant viruses. To develop an efficient, helper virus-free viral recovery system (reverse genetics), a retroviral gene transfer technology was used to establish a stable BHK-21 cell line (designated as BHKT7) which expressed constitutively bacteriophage T7 RNA polymerase (T7 RNAP). An improved method for rescue of infectious foot-and-mouth disease virus (FMDV) was then developed. FMDV full-length cDNA under control of a T7 promotor, was transfected into BHKT7 of differing passages. FMDV virus was rescued efficiently from the BHKT7 cells, the passage number not having an effect on the efficiency of recovery. As a result, the cell line was stable even after multiple passages, expressing sufficient T7 RNAP to support ex vivo transcription and efficient rescue. The reverse genetics system described below is efficient, stable, and convenient. The system could provide not only the basis of gene function research into FMDV, but could also be used for reverse genetics research into other positive-strand RNA viruses, without the need for helper viruses.

Involvement of Caspase-3 Activity and Survivin Downregulation in Cinobufocini-induced Apoptosis in A 549 Cells

Experimental Biology and Medicine (Maywood, N.J.). May, 2009  |  Pubmed ID: 19244543

Cinobufocini injection is a preparation containing water-soluble components of the toad skin. The aim of the present study was to investigate the apoptosis of human lung adenocarcinoma cell line A 549 induced by cinobufocini. A 549 or HLF-1(human lung fibroblast) cells were treated with cinobufocini at different concentrations for 24 and 48 h, respectively. The proliferation of cells was detected with the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay. Morphology of cells was carried out with scanning electronic microscopy (SEM) and Hoechst 33258 staining. The apoptosis rate was examined by flow cytometry. The expression of survivin was examined with RT-PCR and Western blot assay. The caspase-3 and caspase-7 activities were detected with caspase colorimetric protease assay. We found that cinobufocini significantly inhibited tumor growth of A 549 cells in a dose- and time-dependent manner without damaging non-cancerous cells (HLF-1) and induced granular apoptotic bodies of A 549 cells. Next, cinobufocini increased the percentage of cells in G1 phase and decreased the percentage of cells in S phase in A 549 cells. Furthermore, cinobufocini downregulated the expression of survivin mRNA and protein. Finally, cinobufocini upregulated caspase-3 activity. We concluded that cinobufocini induces apoptosis of A 549 cells, which is associated with the decreasing expression of survivin mRNA and protein, increasing caspase-3 activity of A 549 cells.

Regulation of Fibroblast Mitochondrial 27-hydroxycholesterol Production by Active Plasma Membrane Cholesterol

Journal of Lipid Research. Sep, 2009  |  Pubmed ID: 19401598

Side chain oxysterols are cholesterol derivatives thought to signal the abundance of cell cholesterol to homeostatic effector proteins. Here, we investigated how plasma membrane (PM) cholesterol might regulate 27-hydroxycholesterol (HC) biosynthesis in cultured fibroblasts. We showed that PM cholesterol was a major substrate for 27-HC production. Biosynthesis commenced within minutes of loading depleted cells with cholesterol, concurrent with the rapid inactivation of hydroxy-3-methylglutaryl CoA reductase (HMGR). 27-HC production rose approximately 30-fold in normal and Niemann-Pick C1 fibroblasts when PM cholesterol was increased by approximately 60%. 27-HC production was also stimulated by 1-octanol, which displaces PM cholesterol from its phospholipid complexes and thereby increases its activity (escape tendency) and elevates its intracellular abundance. Conversely, lysophosphatidylserine and U18666A inhibited 27-HC biosynthesis and the inactivation of HMGR, presumably by reducing the activity of PM cholesterol and, therefore, its circulation to mitochondria. We conclude that, in this in vitro system, excess (active) PM cholesterol rapidly reaches mitochondria where, as the rate-limiting substrate, it stimulates 27-HC biosynthesis. The oxysterol product then promotes the rapid degradation of HMGR, along with other homeostatic effects. The regulation of 27-HC production by the active excess of PM cholesterol can thus provide a feedback mechanism in the homeostasis of PM cholesterol.

[Beta-elemene Inhibits Expression of ANG II and RhoA/ROCK Signaling in Hepatic Stellate Cells]

Zhongguo Zhong Yao Za Zhi = Zhongguo Zhongyao Zazhi = China Journal of Chinese Materia Medica. Feb, 2009  |  Pubmed ID: 19459312

To investigate the influence of beta-Elemene on expression of ANG II and RhoA/ROCK signaling in Hepatic Stellate Cells.

Posttranslational Elevation of Cell Wall Invertase Activity by Silencing Its Inhibitor in Tomato Delays Leaf Senescence and Increases Seed Weight and Fruit Hexose Level

The Plant Cell. Jul, 2009  |  Pubmed ID: 19574437

Invertase plays multiple pivotal roles in plant development. Thus, its activity must be tightly regulated in vivo. Emerging evidence suggests that a group of small proteins that inhibit invertase activity in vitro appears to exist in a wide variety of plants. However, little is known regarding their roles in planta. Here, we examined the function of INVINH1, a putative invertase inhibitor, in tomato (Solanum lycopersicum). Expression of a INVINH1:green fluorescent protein fusion revealed its apoplasmic localization. Ectopic overexpression of INVINH1 in Arabidopsis thaliana specifically reduced cell wall invertase activity. By contrast, silencing its expression in tomato significantly increased the activity of cell wall invertase without altering activities of cytoplasmic and vacuolar invertases. Elevation of cell wall invertase activity in RNA interference transgenic tomato led to (1) a prolonged leaf life span involving in a blockage of abscisic acid-induced senescence and (2) an increase in seed weight and fruit hexose level, which is likely achieved through enhanced sucrose hydrolysis in the apoplasm of the fruit vasculature. This assertion is based on (1) coexpression of INVINH1 and a fruit-specific cell wall invertase Lin5 in phloem parenchyma cells of young fruit, including the placenta regions connecting developing seeds; (2) a physical interaction between INVINH1 and Lin5 in vivo; and (3) a symplasmic discontinuity at the interface between placenta and seeds. Together, the results demonstrate that INVINH1 encodes a protein that specifically inhibits the activity of cell wall invertase and regulates leaf senescence and seed and fruit development in tomato by limiting the invertase activity in planta.

Apolipoprotein E on Hepatitis C Virion Facilitates Infection Through Interaction with Low-density Lipoprotein Receptor

Virology. Nov, 2009  |  Pubmed ID: 19751943

Hepatitis C virus (HCV) infection is a major cause of liver disease. HCV associates with host apolipoproteins and enters hepatocytes through complex processes involving some combination of CD81, claudin-1, occludin, and scavenger receptor BI. Here we show that infectious HCV resembles very low density lipoprotein (VLDL) and that entry involves co-receptor function of the low-density lipoprotein receptor (LDL-R). Blocking experiments demonstrate that beta-VLDL itself or anti-apolipoprotein E (apoE) antibody can block HCV entry. Knockdown of the LDL-R by treatment with 25-hydroxycholesterol or siRNA ablated ligand uptake and reduced HCV infection of cells, whereas infection was rescued upon cell ectopic LDL-R expression. Analyses of gradient-fractionated HCV demonstrate that apoE is associated with HCV virions exhibiting peak infectivity and dependence upon the LDL-R for cell entry. Our results define the LDL-R as a cooperative HCV co-receptor that supports viral entry and infectivity through interaction with apoE ligand present in an infectious HCV/lipoprotein complex comprising the virion. Disruption of HCV/LDL-R interactions by altering lipoprotein metabolism may therefore represent a focus for future therapy.

Regulated Endoplasmic Reticulum-associated Degradation of a Polytopic Protein: P97 Recruits Proteasomes to Insig-1 Before Extraction from Membranes

The Journal of Biological Chemistry. Dec, 2009  |  Pubmed ID: 19815544

Polytopic membrane proteins subjected to endoplasmic reticulum (ER)-associated degradation are extracted from membranes and targeted to proteasomes for destruction. The extraction mechanism is poorly understood. One polytopic ER protein subjected to ER-associated degradation is Insig-1, a negative regulator of cholesterol synthesis. Insig-1 is rapidly degraded by proteasomes when cells are depleted of cholesterol, and its degradation is inhibited when sterols accumulate in cells. Insig-2, a functional homologue of Insig-1, is degraded slowly, and its degradation is not regulated by sterols. Here, we report that a single amino acid substitution in Insig-2, Insig-2(L210A), causes Insig-2 to be degraded in an accelerated and sterol-regulated manner similar to Insig-1. In seeking an explanation for the accelerated degradation, we found that proteasomes bind to wild type Insig-1 and mutant Insig-2(L210A) but not to wild type Insig-2, whereas the proteins are still embedded in cell membranes. This binding depends on at least two factors, ubiquitination of Insig and association with the ATPase p97/VCP complex. These data suggest that p97 recruits proteasomes to polytopic ER proteins even before they are extracted from membranes.

Capping Invertase Activity by Its Inhibitor: Roles and Implications in Sugar Signaling, Carbon Allocation, Senescence and Evolution

Plant Signaling & Behavior. Oct, 2009  |  Pubmed ID: 19826227

Since the initial biochemical study of a putative invertase inhibitor half a century ago, it has remained as a puzzle as whether such an inhibitory protein indeed limits invertase activity in vivo and, if it does, what is the developmental or physiological significance of such an interaction? Recently, we demonstrated that an invertase inhibitor, INVINH1, specifically inhibited cell wall invertase activity in tomato and Arabidopsis. Silencing INVINH1 expression in tomato released a significant amount of extra cell wall invertase activity. This posttranslational elevation of invertase activity resulted in a blockage of ABA-induced leaf senescence and an increase in fruit sugar levels and seed weight. Here, we discuss the implication of the findings and propose a model that the invertse inhibitor may act as a key modulator in controlling leaf longevity and seed development to ensure success during plant evolution. This may be achieved by optimizing carbon and nitrogen allocation and sugar signaling via interaction between invertase and inhibitor. The discoveries open up exciting new areas for exploring fundamental questions in sugar signaling, carbon allocation and plant development as well as avenues for improving crop productivity.

[Treatment of Frontal Sinus Diseases Via Combined Transfrontal and Intranasal Endoscopic Approaches]

Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi = Chinese Journal of Otorhinolaryngology Head and Neck Surgery. Jul, 2009  |  Pubmed ID: 19957648

To summarize the clinical experience of treatment of frontal sinus diseases via combined transfrontal and intranasal endoscopic approaches, and to explore its indications.

Recovery of Infectious Foot-and-mouth Disease Virus from Full-length Genomic CDNA Clones Using an RNA Polymerase I System

Acta Biochimica Et Biophysica Sinica. Dec, 2009  |  Pubmed ID: 20011974

The prototypic foot-and-mouth disease virus (FMDV) was shown more than a century ago to be the first filterable agent capable of causing FMD, and it has served as an important model for studying basic principles of Aphthovirus molecular biology. However, the complex structure and antigenic diversity of FMDV have posed a major obstacle to the attempts at manipulating the infectious virus by reverse genetic techniques. Here, we report the recovery of infectious FMDV from cDNAs based on an efficient in vivo RNA polymerase I (polI) transcription system. Intracellular transcription of the full-length viral genome from polI-based vectors resulted in efficient formation of infectious virus displaying a genetic marker. Compared with wild-type virus, an abundance of genomic mRNA and elevated expression levels of viral antigens were indicative of the hyperfunction throughout the life-cycle of this cDNA-derived virus at transcription, replication, and translation levels. The technology described here could be an extremely valuable molecular biology tool for studying FMDV complex infectious characteristics. It is an operating platform for studying FMDV functional genomics, molecular mechanism of pathogenicity and variation, and lays a solid foundation for the development of viral chimeras toward the prospect of a genetically engineered vaccine.

[Mutation and Expression of Tumor Suppressor Gene Phosphatase and Tensin Homolog Deleted in Chromosome 10 in Oral Squamous Cell Carcinoma]

Zhonghua Kou Qiang Yi Xue Za Zhi = Zhonghua Kouqiang Yixue Zazhi = Chinese Journal of Stomatology. Nov, 2009  |  Pubmed ID: 20079266

To investigate the role of mutation and mRNA expression of tumor suppressor gene phosphatase and tensin homolog deleted in chromosome 10 (PTEN) in tumorigenesis and progression of oral squamous cell carcinoma (OSCC).

[Correlation Between Clinic and Polysomnographic Findings in Children with Obstructive Sleep Apnea Hypopnea Syndrome]

Lin Chuang Er Bi Yan Hou Tou Jing Wai Ke Za Zhi = Journal of Clinical Otorhinolaryngology, Head, and Neck Surgery. Sep, 2009  |  Pubmed ID: 20120863

To evaluate the correlation between the polysomnographic findings and the degree of obstruction caused by adenoid and tonsillar hypertrophy in children with clinical history of apnea.

[Ursodeoxycholic Acid Inhibits Hepatocyte-like Cell Apoptosis by Down-regulating the Expressions of Bax and Caspase-3]

Zhonghua Yi Xue Za Zhi. Nov, 2009  |  Pubmed ID: 20137712

To investigate the mechanism of ursodeoxycholic acid (UDCA) in hepatocyte apoptosis using differentiated hepatocytes derived from bone marrow mesenchymal cells.

Effects of Feiyanning Decoction on Gene Expression of Nuclear Factor-kappaB Activated by Tumor Necrosis Factor-alpha in Lung Adenocarcinoma Cell Line

Zhong Xi Yi Jie He Xue Bao = Journal of Chinese Integrative Medicine. Mar, 2009  |  Pubmed ID: 19284955

To study the effects of Feiyanning Decoction, a compound traditional Chinese herbal medicine, on gene expression of nuclear factor-kappaB (NF-kappaB) activated by tumor necrosis factor-alpha (TNF-alpha) in lung adenocarcinoma cell line (A549).

Postoperative Respiratory Complications of Adenotonsillectomy for Obstructive Sleep Apnea Syndrome in Older Children: Prevalence, Risk Factors, and Impact on Clinical Outcome

Journal of Otolaryngology - Head & Neck Surgery = Le Journal D'oto-rhino-laryngologie Et De Chirurgie Cervico-faciale. Feb, 2009  |  Pubmed ID: 19344613

To determine the prevalence and type of respiratory complications after adenotonsillectomy for obstructive sleep apnea syndrome (OSAS) in otherwise healthy children with a completed preoperative polysomnography evaluation.

Small Noncoding RNA GcvB is a Novel Regulator of Acid Resistance in Escherichia Coli

BMC Genomics. 2009  |  Pubmed ID: 19379489

The low pH environment of the human stomach is lethal for most microorganisms; but not Escherichia coli, which can tolerate extreme acid stress. Acid resistance in E. coli is hierarchically controlled by numerous regulators among which are small noncoding RNAs (sncRNA).

ANG II-AT1 Receptor Pathway is Involved in the Anti-fibrotic Effect of Beta-elemene

Journal of Huazhong University of Science and Technology. Medical Sciences = Hua Zhong Ke Ji Da Xue Xue Bao. Yi Xue Ying De Wen Ban = Huazhong Keji Daxue Xuebao. Yixue Yingdewen Ban. Apr, 2009  |  Pubmed ID: 19399400

To investigate the effects of beta-elemene on the ANG II-AT1 receptor pathway in rats with liver fibrosis, a model of hepatic fibrosis was induced by hypodermical injection of carbon tetrachloride (CCl4) into Wistar male rats. beta-elemene was intraperitonealy administered into the rats for 8 weeks (0.1 mL/100 g body weight per day). Masson staining was used to observe the liver fibrosis of rats and liver functions were measured by enzymatic kinetic analysis. The content of hydroxyproline in liver tissues was detected by specimen alkaline hydrolysis. The level of plasma ANG in blood II plasma was detected by radioimmunoassay. The expression of AT1R in rat liver were measured using reverse transcriptional-polymerase chain reaction and immunohistochemistry respectively. The results showed that beta-elemene could reduce the collagen disposition in liver and inhibit the progression of liver fibrosis. In addition, the levels of plasma ANG II and the expression of hepatic AT1R in rats with liver fibrosis were also suppressed by beta-elemene. It is concluded that the ANG II-AT1 receptor pathway plays an important role in the development of hepatic fibrosis and beta-elemene could down-regulate the levels of plasma ANG II and the expression of hepatic AT1R in rats with liver fibrosis.

[Effect of Hypoxia and IL-1beta on COX-2 Expression and PGE2 Release in Human Nasal Epithelia]

Lin Chuang Er Bi Yan Hou Tou Jing Wai Ke Za Zhi = Journal of Clinical Otorhinolaryngology, Head, and Neck Surgery. Feb, 2009  |  Pubmed ID: 19452719

To detect cyclooxygenase-2 (COX-2) expression and prostaglandin E2 (PGE2) release in human nasal epithelia (HNE) induced by hypoxia and/or IL-1beta of different time gradient, and to investigate their roles in nasal inflammatory pathogenesis.

[Expression of Hepatocyte-enriched Transcriptional Factors During the Differentiation of Bone Marrow Mesenchymal Stem Cell-derived Hepatocytes]

Zhongguo Yi Xue Ke Xue Yuan Xue Bao. Acta Academiae Medicinae Sinicae. Jun, 2009  |  Pubmed ID: 19621519

To study the expression and distribution of hepatocyte-enriched transcriptional factors during the differentiation of hepatocyte by rat bone marrow stem cells in vitro.

Activation of Membrane Cholesterol by 63 Amphipaths

Biochemistry. Sep, 2009  |  Pubmed ID: 19655814

A few membrane-intercalating amphipaths have been observed to stimulate the interaction of cholesterol with cholesterol oxidase, saponin and cyclodextrin, presumably by displacing cholesterol laterally from its phospholipid complexes. We now report that this effect, referred to as cholesterol activation, occurs with dozens of other amphipaths, including alkanols, saturated and cis- and trans-unsaturated fatty acids, fatty acid methyl esters, sphingosine derivatives, terpenes, alkyl ethers, ketones, aromatics and cyclic alkyl derivatives. The apparent potency of the agents tested ranged from 3 microM to 7 mM and generally paralleled their octanol/water partition coefficients, except that relative potency declined for compounds with >10 carbons. Some small amphipaths activated cholesterol at a membrane concentration of approximately 3 mol per 100 mol of bilayer lipids, about equimolar with the cholesterol they displaced. Lysophosphatidylserine countered the effects of all these agents, consistent with its ability to reduce the pool of active membrane cholesterol. Various amphipaths stabilized red cells against the hemolysis elicited by cholesterol depletion, presumably by substituting for the extracted sterol. The number and location of cis and trans fatty acid unsaturations and the absolute stereochemistry of enantiomer pairs had only small effects on amphipath potency. Nevertheless, potency varied approximately 7-fold within a group of diverse agents with similar partition coefficients. We infer that a wide variety of amphipaths can displace membrane cholesterol by competing stoichiometrically but with only limited specificity for weak association with phospholipids. Any number of other drugs and experimental agents might do the same.

Use of a Riboswitch-controlled Conditional Hypomorphic Mutation to Uncover a Role for the Essential CsrA Gene in Bacterial Autoaggregation

The Journal of Biological Chemistry. Oct, 2009  |  Pubmed ID: 19706608

Essential genes encode biological functions critical for cell survival. Correspondingly, their null mutants are often difficult to obtain, which impedes subsequent genetic and functional analysis. Here, we describe the development and utility of a theophylline-responsive riboswitch that enables target gene expression to be specifically "tuned" from low to high levels, which may be used to generate conditional hypomorphic mutants. Low levels of gene activity in the absence of the ligand (theophylline) permit cell survival, enabling gene activities to be investigated. Normal gene expression levels and wild-type phenotypes can be restored by the addition of the ligand. We demonstrate the utility of this approach with csrA, an essential gene in Escherichia coli that encodes the global regulatory protein CsrA. We placed the theophylline-responsive riboswitch immediately upstream of the csrA ribosome binding site, with the resulting mutant named switch-csrA. Hypomorphism of switch-csrA and its specific responsiveness to theophylline were verified by phenotypic examination and translation analysis. The utility of switch-csrA revealed a previously unidentified function for CsrA, namely its role as a repressor of cellular autoaggregation. Specifically, switch-csrA in the non-ligand-bound form produced low levels of CsrA, and its cells autoaggregated. Theophylline binding induced conformational changes in the riboswitch and permitted efficient csrA translation; consequently, autoaggregation did not occur. Our results indicate that CsrA modulates autoaggregation via the polysaccharide adhesin poly-beta-1,6-N-acetyl-D-glucosamine. In summary, the use of ligand-responsive riboswitches to construct conditional hypomorphic mutants represents a novel approach for investigating the activities of essential genes, which effectively complements traditional genetic approaches.

Vaccination with a Chaperone Complex Based on PSCA and GRP170 Adjuvant Enhances the CTL Response and Inhibits the Tumor Growth in Mice

Vaccine. Aug, 2010  |  Pubmed ID: 20637304

Increasing knowledge demonstrate that prostate stem cell antigen (PSCA) is a promising candidate for immunotherapy of advanced prostate cancer. However, tumor escape with down-regulation of target antigens may limit the susceptibility of tumor cells to the immune attack. Concomitant generation of T-cell responses against several immunodominant antigens may circumvent this potential drawback. In this study, we prepared the chaperone complex vaccine based on PSCA and GRP170, and utilized it to immunize the C57BL/6 mice. In addition, the T-cell response was monitored with ELISPOT and (51)Cr-release assays, and the tumor growth and the life span of tumor-bearing mice were assessed. The results demonstrated the chaperone complex based on PSCA and GRP170 could enhance the T-cell mediate immune responses, which significantly inhibited the tumor growth and prolonged the life span of tumor-bearing mice. In conclusion, our findings supported the strategy of chaperone complex, based on PSCA and GRP170, could be an effective treatment for prostate cancer therapy.

Sugar Input, Metabolism, and Signaling Mediated by Invertase: Roles in Development, Yield Potential, and Response to Drought and Heat

Molecular Plant. Nov, 2010  |  Pubmed ID: 20729475

Invertase (INV) hydrolyzes sucrose into glucose and fructose, thereby playing key roles in primary metabolism and plant development. Based on their pH optima and sub-cellular locations, INVs are categorized into cell wall, cytoplasmic, and vacuolar subgroups, abbreviated as CWIN, CIN, and VIN, respectively. The broad importance and implications of INVs in plant development and crop productivity have attracted enormous interest to examine INV function and regulation from multiple perspectives. Here, we review some exciting advances in this area over the last two decades, focusing on (1) new or emerging roles of INV in plant development and regulation at the post-translational level through interaction with inhibitors, (2) cross-talk between INV-mediated sugar signaling and hormonal control of development, and (3) sugar- and INV-mediated responses to drought and heat stresses and their impact on seed and fruit set. Finally, we discuss major questions arising from this new progress and outline future directions for unraveling mechanisms underlying INV-mediated plant development and their potential applications in plant biotechnology and agriculture.

[The Clinical Characteristics of the Benign Paroxysmal Positional Vertigo Associated with Meniere's Disease]

Zhonghua Yi Xue Za Zhi. Jul, 2010  |  Pubmed ID: 20979913

To explore the clinical characteristics of the benign paroxysmal positional vertigo (BPPV) associated with Meniere's disease (MD) in retrospect in an effort to improve the diagnosis and efficacy of treatment.

Identification of Ubxd8 Protein As a Sensor for Unsaturated Fatty Acids and Regulator of Triglyceride Synthesis

Proceedings of the National Academy of Sciences of the United States of America. Dec, 2010  |  Pubmed ID: 21115839

Fatty acids (FAs) are essential for cell survival, yet their overaccumulation causes lipotoxicity. To prevent lipotoxicity, cells store excess FAs as triglycerides (TGs). In cultured cells TG synthesis is activated by excess unsaturated but not saturated FAs. Here, we identify Ubxd8 as a sensor for unsaturated FAs and regulator of TG synthesis. In cultured cells depleted of FAs, Ubxd8 inhibits TG synthesis by blocking conversion of diacylglycerols (DAGs) to TGs. Excess unsaturated but not saturated FAs relieve this inhibition. As a result, unsaturated FAs are incorporated into TGs, whereas saturated FAs are incorporated into DAGs. In vitro, unsaturated but not saturated FAs alter the structure of purified recombinant Ubxd8 as monitored by changes in its thermal stability, trypsin cleavage pattern, and oligomerization. These results suggest that Ubxd8 acts as a brake that limits TG synthesis, and this brake is released when its structure is altered by exposure to unsaturated FAs.

[Clinical Research and Preliminarily Exploration of Genetic Basis on a Hereditary Hemochromatosis Pedigree]

Zhonghua Gan Zang Bing Za Zhi = Zhonghua Ganzangbing Zazhi = Chinese Journal of Hepatology. Nov, 2010  |  Pubmed ID: 21138633

To describe the clinical features of a hereditary hemochromatosis pedigree and to explore preliminarily the genetic basis of this pedigree.

[Endoscopic Endonasal Anatomy of Pterygopalatine Fossa and Infratemporal Fossa: Comparison of Endoscopic and Radiological Landmarks]

Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi = Chinese Journal of Otorhinolaryngology Head and Neck Surgery. Oct, 2010  |  Pubmed ID: 21176577

To investigate the feasibility and reliability of the measurement of critical anatomic landmarks of endoscopic endonasal anatomy of pterygopalatine fossa and infratemporal fossa using multislice spiral computed tomography (MSCT), and to illustrate the spatial relationship of the surgical landmarks in pterygopalatine fossa and infratemporal fossa through an endoscopic endonasal view and radiological images.

Identification and Assessment of Permeability Enhancing Vehicles for Transdermal Delivery of Glucosamine Hydrochloride

Archives of Pharmacal Research. Feb, 2010  |  Pubmed ID: 20195831

As an initial step to develop the transdermal delivery system of glucosamine hydrochloride (GL-HCl), the permeation study across the rat skin in vitro was performed to identify the most efficient vehicle with regard to the ability to deliver GL-HCl transdermally. The GL-HCl formulations such as o/w cream, liposome suspension, liposomal gel, and liquid crystalline vehicles were prepared and compared for transdermal flux of GL-HCl. The liquid crystalline vehicles were more effective in increasing the skin permeation of GL-HCl than o/w cream and liposomal vehicles. Of the liquid crystalline vehicles tested, the permeation enhancing ability of the cubic phase was greater than that of the hexagonal phase when the nanoparticle dispersion was used. The skin permeation enhancing ability of the cubic nanoparticles for GL-HCl was further increased by employing both oleic acid and polyethylene glycol 200. Therefore, the cubic liquid crystalline nanodispersion containing oleic acid and PEG 200 can provide a possibility of clinical application of transdermal GL-HCl.

Serological Profiling of a Candida Albicans Protein Microarray Reveals Permanent Host-pathogen Interplay and Stage-specific Responses During Candidemia

PLoS Pathogens. Mar, 2010  |  Pubmed ID: 20361054

Candida albicans in the immunocompetent host is a benign member of the human microbiota. Though, when host physiology is disrupted, this commensal-host interaction can degenerate and lead to an opportunistic infection. Relatively little is known regarding the dynamics of C. albicans colonization and pathogenesis. We developed a C. albicans cell surface protein microarray to profile the immunoglobulin G response during commensal colonization and candidemia. The antibody response from the sera of patients with candidemia and our negative control groups indicate that the immunocompetent host exists in permanent host-pathogen interplay with commensal C. albicans. This report also identifies cell surface antigens that are specific to different phases (i.e. acute, early and mid convalescence) of candidemia. We identified a set of thirteen cell surface antigens capable of distinguishing acute candidemia from healthy individuals and uninfected hospital patients with commensal colonization. Interestingly, a large proportion of these cell surface antigens are involved in either oxidative stress or drug resistance. In addition, we identified 33 antigenic proteins that are enriched in convalescent sera of the candidemia patients. Intriguingly, we found within this subset an increase in antigens associated with heme-associated iron acquisition. These findings have important implications for the mechanisms of C. albicans colonization as well as the development of systemic infection.

Diagnosis and Phylogenetic Analysis of Orf Virus from Goats in China: a Case Report

Virology Journal. 2010  |  Pubmed ID: 20416112

Orf virus (ORFV) is the etiological agent of contagious pustular dermatitis and is the prototype of the genus Parapoxvirus (PPV). It causes a severe exanthematous dermatitis that afflicts domestic and wild small ruminants.

Medicine. HDL MiR-ed Down by SREBP Introns

Science (New York, N.Y.). Jun, 2010  |  Pubmed ID: 20558698

A Room-temperature Reactive-template Route to Mesoporous ZnGa2O4 with Improved Photocatalytic Activity in Reduction of CO2

Angewandte Chemie (International Ed. in English). Aug, 2010  |  Pubmed ID: 20652925

Outcome of Adenotonsillectomy for Obstructive Sleep Apnea Syndrome in Children

The Annals of Otology, Rhinology, and Laryngology. Aug, 2010  |  Pubmed ID: 20860275

We evaluated the outcome of adenotonsillectomy for obstructive sleep apnea syndrome (OSAS) in children using polysomnography (PSG) data and a quality-of-life (QOL) instrument.

[Clinical Research on the Quality of Life in Patients with Allergic Rhinitis]

Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi = Chinese Journal of Otorhinolaryngology Head and Neck Surgery. Jun, 2010  |  Pubmed ID: 21055320

To explore the quality of life (QOL) outcome in patients with allergic rhinitis (AR).

Construction of a DNA Vaccine Encoding Flk-1 Extracellular Domain and C3d Fusion Gene and Investigation of Its Suppressing Effect on Tumor Growth

Cancer Immunology, Immunotherapy : CII. Jan, 2010  |  Pubmed ID: 19543726

Although the critical role of complement component C3d as a molecular adjuvant in preventing virus infection is well established, its role in cancer prophylaxis and treatment is unclear. In this study, we constructed a recombinant plasmid encoding Flk-1 and C3d3 fusion proteins and investigated its transient expression in vitro in transfected eukaryotic cells and its antibody response in immunized mice. Subsequently, we investigated the vaccine's ability to elicit an immune response leading to suppression of angiogenesis and tumor growth in mice bearing bladder transitional cell carcinoma. Using Western blotting, immunocytochemistry, and flow cytometry, we detected the expression of Flk-1 and C3d3 fusion proteins in COS-7 cells transfected with these recombinant plasmids. Further binding experiment using CR2 (C3d receptor) positive Raji cells that were incubated with transfected COS-7 supernatant indicated that C3d was successfully fused to Flk-1. Although both vaccines elicited peak antibody levels at 5 weeks, Flk-1-specific antibody titer in pSG.SS.Flk-1(ECD).C3d3.YL-immunized mice was significantly higher when compared to pSG.SS.Flk-1(ECD).YL-immunized mice. The results of experiments with bladder tumor-bearing mice showed that the vaccine inhibited tumor growth significantly. These results suggest that C3d plays a critical role in tumor immunotherapy by promoting antibody response in Flk-1-based DNA vaccines. This approach may provide a new strategy for the rational design of anti-angiogenic therapies for the treatment of solid tumors and provide a basis for the further exploitation and application of the anti-angiogenesis DNA vaccines.

Unmasking of LPA1 Receptor-mediated Migration Response to Lysophosphatidic Acid by Interleukin-1β-induced Attenuation of Rho Signaling Pathways in Rat Astrocytes

Journal of Neurochemistry. Apr, 2011  |  Pubmed ID: 21244430

Action mechanism of lipopolysaccharide (LPS), interleukin-1β (IL-1β), and lysophosphatidic acid (LPA) to regulate motility, an important process of astrogliosis, was investigated in rat astrocytes. While LPA exerted no significant effect on the cell migration, the prior treatment of the cells with LPS or IL-1β resulted in the appearance of migration activity in response to LPA. The LPS induction of the migration response to LPA was associated with the production of IL-1β precursor protein and inhibited by the IL-1 receptor antagonist. The IL-1β treatment also allowed LPA to activate Rac1. The LPA-induced Rac1 activation and migration were inhibited by pertussis toxin, a small interfering RNA specific to LPA(1) receptors, and LPA(1) receptor antagonists, including Ki16425. However, the IL-1β treatment had no appreciable effect on LPA(1) receptor mRNA expression and LPA-induced activation of ERK, Akt, and proliferation. The induction of the migration response to LPA by IL-1β was inhibited by a constitutively active RhoA. Moreover, LPA significantly activated RhoA through the LPA(1) receptor in the control cells but not in the IL-1β-treated cells. These results suggest that IL-1β inhibits the LPA(1) receptor-mediated Rho signaling through the IL-1 receptor, thereby disclosing the LPA(1) receptor-mediated G(i) protein/Rac/migration pathway.

Plasma Nitric Oxide and Left Ventricular Function in Rabbits After Cardiac Lymphatic Obstruction

Bosnian Journal of Basic Medical Sciences / Udruženje Basičnih Mediciniskih Znanosti = Association of Basic Medical Sciences. Feb, 2011  |  Pubmed ID: 21342136

This study was designed to investigate the effect of cardiac lymphatic obstruction on plasma nitric oxide (NO) and left ventricular function. The plasma NO was measured in study group (n = 21) and control group rabbits (n = 12) before, and 3, 7, 14, 30 and 90 days after the obstruction of cardiac lymphatic vessels. Left ventricular ejection fraction was measured with echocardiography. There was a significant reduction in the left ventricular ejection fraction following the lymphatic obstruction (0.72±0.02 vs. 0.61±0.02, p<0.01). Plasma NO in the control group remained unchanged during the observation period (54.2±4.4 vs. 52.0±4.2 μmol/L, p>0.05). In the study group, there was a small but significant increase in the plasma NO on day 3, 7 and 14 following the lymphatic obstruction (52.3±4.1 vs. 73.4±5.9 μmol/L, p<0.01). The plasma NO returned to the baseline levels on day 30 but reduced to 44.9±3.6 μmol/L on 90 days after the lymphatic obstruction (p<0.05). In conclusion, cardiac lymphatic obstruction was associated with a significant reduction in left ventricular function. It was also associated with an increase in the plasma NO in the first 2 weeks but there was a significant reduction in the NO levels three months after the lymphatic obstruction.

Physico-chemical Characteristics and Free Fatty Acid Composition of Dry Fermented Mutton Sausages As Affected by the Use of Various Combinations of Starter Cultures and Spices

Meat Science. Aug, 2011  |  Pubmed ID: 21458169

The microbiological, physico-chemical and free fatty acid composition of dry fermented mutton sausages were determined during ripening and storage. Three sausage mixtures (starter culture [SC], SC and black pepper [SC+BP] and SC, BP and cumin [SC+BP+C]) were compared with a control (CO). In general, the lactic acid bacteria populations in the SC+BP increased significantly to 9 log CFU/g and were higher than the CO (8 log CFU/g) (P<0.05) from fermentation to ripening. The pH values of the SC, SC+BP and SC+BP+C were 4.81, 4.55 and 4.53 respectively, significantly lower (P<0.05) than the CO at the end of fermentation. The water activity (a(w)) in all sausages decreased significantly to 0.88 at Day 7. The total free fatty acid (TFFA) in the treatments increased significantly (P<0.05) during ripening and storage. The levels of MUFA+PUFA/SFA in SC+BP and SC+BP+C at Day 7 were 2.44 and 2.31 respectively, higher than the control (1.65) (P>0.05).

[Role of MicroRNA-223 and Its Target Gene Oncogene C-myc in Hepatocellular Carcinoma Pathogenesis.]

Zhonghua Gan Zang Bing Za Zhi = Zhonghua Ganzangbing Zazhi = Chinese Journal of Hepatology. Feb, 2011  |  Pubmed ID: 21492514

To investigate the regulatory role of microRNA-223 (miR-223) on c-myc and its role in hepatocarcinogenesis. miR-223 and c-myc mRNA expressions in normal tissue, paraneoplastic tissue, liver cancer tissue and liver cancer cells were tested with microRNA microarray and quantitative real-time PCR (qRT-PCR). C-myc protein expression was detected by Western blot. MiR-223 mimic was transfected into HepG2 cells and the expression changes of c-myc mRNA and protein were tested with qRT-PCR and Western blot respectively. MiR-223 was down-regulated by 61.53% and 30.77% respectively in hepatocellular carcinoma and adjacent tissues as compared to normal liver tissues and the expression of miR-223 was also decreased in HepG2 cell as compared to fetal liver cells L02, whereas the expressions of c-myc mRNA and protein increased in paraneoplastic and HCC tissues compared with normal liver tissues. It prompts that the expressions of miR-223 and c-myc are negatively correlated. No obvious difference found among c-myc mRNA expressions after miR-223 mimics transfection. The c-myc abnormal high-expression may play a dynamic role in hepatocarcinogenesis due to the miR-223 down-regulation.

Regulation of Cholesterol and Fatty Acid Synthesis

Cold Spring Harbor Perspectives in Biology. Jul, 2011  |  Pubmed ID: 21504873

In mammals, intracellular levels of cholesterol and fatty acids are controlled through a feedback regulatory system mediated by a family of transcription factors called sterol regulatory element-binding proteins (SREBPs). SREBPs are synthesized as inactive precursors bound to membranes of the endoplasmic reticulum. When cells are deprived of cholesterol and fatty acids, NH(2)-terminal fragments of SREBPs become proteolytically released from membranes and migrate to the nucleus to activate transcription of genes required for lipid synthesis and uptake. Conversely, lipid repletion inhibits proteolytic processing of SREBPs and thereby suppresses lipid accumulation. We review here studies in cultured cells that reveal the mechanism for regulation of SREBP proteolytic activation, and those in animal models in which SREBP proteolysis has been either activated or inhibited to show the essential role of SREBPs in regulating hepatic lipid homeostasis.

In-line Monitoring of Extraction Process of Scutellarein from Erigeron Breviscapus (vant.) Hand-Mazz Based on Qualitative and Quantitative Uses of Near-infrared Spectroscopy

Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy. Sep, 2011  |  Pubmed ID: 21561801

The application of near-infrared (NIR) spectroscopy for in-line monitoring of extraction process of scutellarein from Erigeron breviscapus (vant.) Hand-Mazz was investigated. For NIR measurements, two fiber optic probes designed to transmit NIR radiation through a 2 mm pathlength flow cell were utilized to collect spectra in real-time. High performance liquid chromatography (HPLC) was used as a reference method to determine scutellarein in extract solution. Partial least squares regression (PLSR) calibration model of Savitzky-Golay smoothing NIR spectra in the 5450-10,000 cm(-1) region gave satisfactory predictive results for scutellarein. The results showed that the correlation coefficients of calibration and cross validation were 0.9967 and 0.9811, respectively, and the root mean square error of calibration and cross validation were 0.044 and 0.105, respectively. Furthermore, both the moving block standard deviation (MBSD) method and conformity test were used to identify the end point of extraction process, providing real-time data and instant feedback about the extraction course. The results obtained in this study indicated that the NIR spectroscopy technique provides an efficient and environmentally friendly approach for fast determination of scutellarein and end point control of extraction process.

The Membrane-bound Transcription Factor CREB3L1 is Activated in Response to Virus Infection to Inhibit Proliferation of Virus-infected Cells

Cell Host & Microbe. Jul, 2011  |  Pubmed ID: 21767813

CREB3L1/OASIS is a cellular transcription factor synthesized as a membrane-bound precursor and activated by regulated intramembrane proteolysis in response to stimuli like ER stress. Comparing gene expression between Huh7 subclones that are permissive for hepatitis C virus (HCV) replication versus the nonpermissive parental Huh7 cells, we identified CREB3L1 as a host factor that inhibits proliferation of virus-infected cells. Upon infection with diverse DNA and RNA viruses, including murine γ-herpesvirus 68, HCV, West Nile virus (WNV), and Sendai virus, CREB3L1 was proteolytically cleaved, allowing its NH(2) terminus to enter the nucleus and induce multiple genes encoding inhibitors of the cell cycle to block cell proliferation. Consistent with this, we observed a necessity for CREB3L1 expression to be silenced in proliferating cells that harbor replicons of HCV or WNV. Our results indicate that CREB3L1 may play an important role in limiting virus spread by inhibiting proliferation of virus-infected cells.

Proteomics Analysis of Porcine Serum Proteins by LC-MS/MS After Foot-and-mouth Disease Virus (FMDV) Infection

The Journal of Veterinary Medical Science / the Japanese Society of Veterinary Science. Dec, 2011  |  Pubmed ID: 21799299

To analyze serum proteomics differences between normal and foot and mouth disease virus (FMDV)-infected piglets, an analytical method based on liquid chromatography with tandem mass spectrometry (LC-MS/MS) was used. Samples of venous blood were collected before and after FMDV infection and high abundance serum albumin was removed using a commercial kit. After trypsin digestion, serum samples were processed with LC-MS/MS. Proteins were identified by peptide mass fingerprinting. We found that apolipoprotein A-IV precursor, haptoglobin and probable chemoreceptor glutamine deamidase cheD appeared after FMDV infection in the same piglet. This is believed to be the first time that serum proteomics analysis by LC-MS/MS after FMDV infection has been performed, and our results may provide further information about biomarkers for early diagnosis of FMD in piglets.

Engineering a Portable Riboswitch-LacP Hybrid Device for Two-way Gene Regulation

Nucleic Acids Research. Oct, 2011  |  Pubmed ID: 21803790

Riboswitches are RNA-based regulatory devices that mediate ligand-dependent control of gene expression. However, there has been limited success in rationally designing riboswitches. Moreover, most previous riboswitches are confined to a particular gene and only perform one-way regulation. Here, we used a library screening strategy for efficient creation of ON and OFF riboswitches of lacI on the chromosome of Escherichia coli. We then engineered a riboswitch-LacP hybrid device to achieve portable gene control in response to theophylline and IPTG. Moreover, this device regulated target expression in a 'two-way' manner: the default state of target expression was ON; the expression was switched off by adding theophylline and restored to the ON state by adding IPTG without changing growth medium. We showcased the portability and two-way regulation of this device by applying it to the small RNA CsrB and the RpoS protein. Finally, the use of the hybrid device uncovered an inhibitory role of RpoS in acetate assimilation, a function which is otherwise neglected using conventional genetic approaches. Overall, this work establishes a portable riboswitch-LacP device that achieves sequential OFF-and-ON gene regulation. The two-way control of gene expression has various potential scientific and biotechnological applications and helps reveal novel gene functions.

Transumbilical Laparoendoscopic Single-site Renal Pedicle Lymphatic Disconnection for Refractory Chyluria

Journal of Endourology / Endourological Society. Aug, 2011  |  Pubmed ID: 21815794

To report our preliminary techniques and experience with transumbilical laparoendoscopic single-site renal pedicle lymphatic disconnection (LESS-RPLD) in seven patients with refractory chyluria.

Intratympanic Methylprednisolone Improves Hearing Function in Refractory Sudden Sensorineural Hearing Loss: a Control Study

Audiology & Neuro-otology. 2011  |  Pubmed ID: 20948195

The aim of this study was to describe our experience with intratympanic (IT) steroid treatment of sudden sensorineural hearing loss (SSNHL) after the failure of intravenous (IV) steroid treatment and to examine the efficacy of this treatment.

[Compatibility of Three Chemiluminescence Systems in CA153 Detection]

Zhonghua Zhong Liu Za Zhi [Chinese Journal of Oncology]. Feb, 2011  |  Pubmed ID: 21575482

Cell Biology. Protease Sets Site-1 on Lysosomes

Science (New York, N.Y.). Jul, 2011  |  Pubmed ID: 21719668

[In-line Monitoring of Blending Process of Zhongsheng Pill Powder Using Miniature Near-infrared Analyzer]

Zhongguo Zhong Yao Za Zhi = Zhongguo Zhongyao Zazhi = China Journal of Chinese Materia Medica. Nov, 2011  |  Pubmed ID: 22308684

To establish a simple and rapid method based on diffuse reflectance NIR spectra to in-line monitor the blending process of Zhongsheng pill powder.

Diagnosis and Treatment of Hyper-Delayed Graft Function After Renal Transplantation

Urologia Internationalis. Feb, 2012  |  Pubmed ID: 22327625

Background: Renal transplant recipients may experience delayed graft function (DGF), but recovery can take many months, a condition we define as hyper-delayed graft function (HDGF). Methods: A retrospective review of 50 renal transplant recipients who had HDGF and comparison with patients who had immediate graft function (IGF) and DGF. Results: Acute renal tube necrosis (ATN) during or soon after surgery was the most common cause of HDGF. Following standard treatment, 48 HDGF patients transitioned from oliguria to polyuria in 45 days (± 3) and renal function of the kidney fully recovered in 73 days (± 1). These HDGF patients had similar overall survival and kidney survival rates as IGF and DGF patients who were matched for age, sex, primary underlying disease, tissue matching, warm and cold ischemia time, and surgery time. Conclusions: Appropriate care and monitoring of HDGF patients allows them to regain normal renal function and to achieve patient and renal survival rates similar to those of IGF and DGF patients.

Pedicled Greater Omentum Graft: a New Technique to Repair Recurrent Urinary Fistulae After Kidney Transplantation

Cell Biochemistry and Biophysics. Jan, 2012  |  Pubmed ID: 21833672

Urinary fistula is the most frequent urologic complication within the first month after kidney transplantation, which often leads to graft loss and mortality. Open surgery is the most popular approach for the treatment of these fistulae; however, it is associated with high failure rates. Here, we present a new technique of pedicled greater omentum graft to repair recurrent urinary fistulae after kidney transplantation. We used this technique in the repair of recurrent urinary fistulae in 13 post-kidney transplant patients. All operations were successful at the first attempt, and there was no fistula recurrence. Further, no complications associated with the technique have been observed during the follow-up (1-7 years). In conclusion, the use of pedicled greater omentum graft for the repair of recurrent urinary fistulae after kidney transplantation is both effective and safe.

Genetic Characterization of a New Pandemic Southeast Asia Topotype Strain of Serotype O Foot-and-mouth Disease Virus Isolated in China During 2010

Virus Genes. Feb, 2012  |  Pubmed ID: 21932049

The full-length nucleotide sequence of the foot-and-mouth disease virus O/BY/CHA/2010 strain, Mya-98 lineage of Southeast Asia (SEA) topotype, was determined and compared with O/HKN/20/2010 and other known FMDV strains. Homology analysis indicated >98.0% nucleotide identity between O/BY/CHA/2010 and the epidemic strains, O/HKN/20/2010, and O/VN/2009. However, with the exception of the VP4, 2A, and 3BCD regions, O/BY/CHA/2010 showed a lower similarity with SEA topotype strains, O/VN/2006, and HLJOC12/03. A comparison of O/BY/CHA/2010 with non-SEA topotype strains showed the highest level of homology (97.4-100%) with UKG/7B/2007, Akesu/58, and the PanAsia strains in the 2A, P2, and 3CD regions, which suggested the presence of similar characteristics among these strains. Phylogenetic analysis revealed that O/BY/CHA/2010 is clustered in the Mya-98 lineage of the SEA topotype and is linked to four other isolates: HKN/20/2010, O/VN/2009, O/VN/2006, and HLJOC12/03. The VP1-based phylogenetic tree was divided into distinct clusters according to the different topotypes, while other gene-based phylogenetic trees exhibited some degree of intercrossing among topotypes. Furthermore, sequence analysis of the Lpro gene revealed a single amino acid insertion in O/HKN/20/2010 and a single amino acid deletion in O/BY/CHA/2010, in addition to a 70-nucleotide deletion within the 5'-untranslated region of O/HKN/20/2010. The majority of strains were shown to be homologous in the pseudoknots region although some exceptions were noted. This study provides a comprehensive genetic characterization of a novel FMDV isolate of the Mya-98 lineage.

High Invertase Activity in Tomato Reproductive Organs Correlates with Enhanced Sucrose Import Into, and Heat Tolerance Of, Young Fruit

Journal of Experimental Botany. Feb, 2012  |  Pubmed ID: 22105847

Heat stress can cause severe crop yield losses by impairing reproductive development. However, the underlying mechanisms are poorly understood. We examined patterns of carbon allocation and activities of sucrose cleavage enzymes in heat-tolerant (HT) and -sensitive (HS) tomato (Solanum lycopersicum L.) lines subjected to normal (control) and heat stress temperatures. At the control temperature of 25/20 °C (day/night) the HT line exhibited higher cell wall invertase (CWIN) activity in flowers and young fruits and partitioned more sucrose to fruits but less to vegetative tissues as compared to the HS line, independent of leaf photosynthetic capacity. Upon 2-, 4-, or 24-h exposure to day or night temperatures of 5 °C or more above 25/20 °C, cell wall (CWIN) and vacuolar invertases (VIN), but not sucrose synthase (SuSy), activities in young fruit of the HT line were significantly higher than those of the HS line. The HT line had a higher level of transcript of a CWIN gene, Lin7, in 5-day fruit than the HS line under control and heat stress temperatures. Interestingly, heat induced transcription of an invertase inhibitor gene, INVINH1, but reduced its protein abundance. Transcript levels of LePLDa1, encoding phospholipase D, which degrades cell membranes, was less in the HT line than in the HS line after exposure to heat stress. The data indicate that high invertase activity of, and increased sucrose import into, young tomato fruit could contribute to their heat tolerance through increasing sink strength and sugar signalling activities, possibly regulating a programmed cell death pathway.

Saucerneol F, a New Lignan, Inhibits INOS Expression Via MAPKs, NF-κB and AP-1 Inactivation in LPS-induced RAW264.7 Cells

International Immunopharmacology. Jan, 2012  |  Pubmed ID: 22155103

Saucerneol F (SF), a new tetrahydrofuran-type sesquilignan isolated from Saururus chinensis, dose-dependently inhibited nitric oxide (NO) production, with concomitant reduction of inducible nitric oxide synthase (iNOS) protein and mRNA expression in lipopolysaccharide (LPS)-stimulated murine macrophage RAW264.7 cells. To elucidate the molecular mechanism underlying the inhibition of iNOS expression by SF, we assessed the effects of SF on nuclear factor-κB (NF-κB) DNA-binding activity, NF-κB-dependent reporter gene activity, inhibitory factor-κB (IκB) phosphorylation and degradation, and p65 nuclear translocation. Treatment with SF decreased the luciferase activities of NF-κB reporter promoters in a dose-dependent manner and translocation of NF-κB p65. In addition, pretreatment of SF reduced LPS-stimulated activation of mitogen-activated protein kinases (MAPKs) including extracellular signal-regulated kinase 1/2 (ERK1/2), p38 MAPK, and c-Jun NH(2)-terminal kinase (JNK). Furthermore, SF attenuated the luciferase activities of AP-1 reporter promoters and the DNA-binding capacity of AP-1. Taken together, the present results indicate that SF attenuates NO production and iNOS expression by blocking LPS-induced activation of NF-κB, MAPKs, and AP-1, suggesting that SF is potentially applicable as an anti-inflammatory drug.

Activation Mobilizes the Cholesterol in the Late Endosomes-lysosomes of Niemann Pick Type C Cells

PloS One. 2012  |  Pubmed ID: 22276143

A variety of intercalating amphipaths increase the chemical activity of plasma membrane cholesterol. To test whether intracellular cholesterol can be similarly activated, we examined NPC1 and NPC2 fibroblasts, since they accumulate large amounts of cholesterol in their late endosomes and lysosomes (LE/L). We gauged the mobility of intracellular sterol from its appearance at the surface of the intact cells, as determined by its susceptibility to cholesterol oxidase and its isotope exchange with extracellular 2-(hydroxypropyl)-β-cyclodextrin-cholesterol. The entire cytoplasmic cholesterol pool in these cells was mobile, exchanging with the plasma membrane with an apparent half-time of ∼3-4 hours, ∼4-5 times slower than that for wild type human fibroblasts (half-time ∼0.75 hours). The mobility of the intracellular cholesterol was increased by the membrane-intercalating amphipaths chlorpromazine and 1-octanol. Chlorpromazine also promoted the net transfer of LE/L cholesterol to serum and cyclodextrin. Surprisingly, the mobility of LE/L cholesterol was greatly stimulated by treating intact NPC cells with glutaraldehyde or formaldehyde. Similar effects were seen with wild type fibroblasts in which the LE/L cholesterol pool had been expanded using U18666A. We also showed that the cholesterol in the intracellular membranes of fixed wild-type fibroblasts was mobile; it was rapidly oxidized by cholesterol oxidase and was rapidly replenished by exogenous sterol. We conclude that a) the cholesterol in NPC cells can exit the LE/L (and the extensive membranous inclusions therein) over a few hours; b) this mobility is stimulated by the activation of the cholesterol with intercalating amphipaths; c) intracellular cholesterol is even more mobile in fixed cells; and d) amphipaths that activate cholesterol might be useful in treating NPC disease.

Natural Vanadium-containing Jeju Groundwater Inhibits Immunoglobulin E-mediated Anaphylactic Reaction and Suppresses Eicosanoid Generation and Degranulation in Bone Marrow Derived-mast Cells

Biological & Pharmaceutical Bulletin. 2012  |  Pubmed ID: 22293352

The high-affinity receptor for immunoglobulin E (IgE) (FcεRI)-mediated activation of mast cells plays an important role in various allergic diseases. To assess the anti-allergic activity of natural vanadium-containing Jeju groundwater (JW), an in vivo passive cutaneous anaphylaxis (PCA) animal model and in vitro mouse bone marrow-derived mast cells (BMMCs) was used. JW inhibited cyclooxygenase-2 (COX-2)-dependent prostaglandin D(2) (PGD(2)) generation in a dose-dependent manner, with a concomitant reduction of COX-2 protein expression in IgE-induced BMMCs. In addition, JW inhibited 5-lipoxygenase (5-LOX)-dependent generation of leukotriene C(4) (LTC(4)) as well as degranulation in a dose-dependent manner. These results demonstrate that JW has dual COX-2/5-LOX inhibitory activity. In addition, vanadium pentoxide (V(2)O(5)), which is the major vanadium component of JW, also inhibited PGD(2) and LTC(4) generation as well as degranulation in IgE-induced BMMCs. Furthermore, oral administration of JW dose-dependently inhibited mast cell-dependent passive anaphylactic reaction in IgE-sensitized mice. Taken together, these results suggest that JW may be useful in regulating mast cell-mediated allergic response through the suppression of eicosanoid generation and degranulation in mast cells.

Reduced E-cadherin Expression is Associated with Lymph Node Metastases in Laryngeal Squamous Cell Carcinoma

Auris, Nasus, Larynx. Apr, 2012  |  Pubmed ID: 21570223

To investigate the expression of E-cadherin and its relationship with clinicopathological parameters in laryngeal squamous cell carcinoma (LSCC).