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Find video protocols related to scientific articles indexed in Pubmed.
Epigallocatechin-3-gallate (EGCG) inhibits 3-hydroxy-3-methylglutaryl-CoA reductase in the presence of glycerol.
Pak J Pharm Sci
PUBLISHED: 11-03-2014
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The inhibition of 3-hydroxy-3-methylglutaryl CoA reductase (HMGCR) is considered able to decrease serum cholesterol levels and dramatically reduce the risk for cardiovascular and cerebrovascular diseases. The statins, competitive inhibitors of HMGCR, have been employed to control hypercholesterolemia. But their side effects, especially their safety of long-term administration have attracted great attention. Therefore, there is still an urgent requirement for the development of safer inhibitors of HMGCR with less serious side effects. In this study, we cloned and purified the catalytic domain of human HMGCR (?HMGCR), and applied the method of Ultra Performance Liquid Chromatography (UPLC) to assay ?HMGCR activity and screen its inhibitors from natural products. The results indicated that EGCG can inhibit ?HMGCR in the presence of some glycerol in vitro and can decrease cellular total cholesterol in HepG2 cells. As a consequence, it is promising to put EGCG into the development of hypolipidemic health product.
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The effect of rhubarb pre-treatment on intestinal microcirculation in septic rats.
Am. J. Chin. Med.
PUBLISHED: 09-01-2014
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The intestine plays a vital role in the pathophysiology of sepsis development. The objective of the present study was to explore the effects of rhubarb on intestinal microcirculation in septic rats. We used moorFLPI laser speckle imaging to detect the blood flow of the intestinal mucosa and wall. Using an ELISA, we assayed the concentration of lactate (L) and pyruvic acid (P) in the intestinal tissue to calculate the ratio of lactate to pyruvic acid (L/P ratio). To observe the intestinal mucosal capillaries, gelatin and ink were perfused into the intestine and subsequently stained with hematoxylin and eosin (HE) to measure the ratio of the vessel area. We then used immunohistochemistry to measure CD31 expression. Using an MTT assay, the effect of the rhubarb extract on the proliferation of human umbilical vein endothelial cells (HUVECs) was analyzed. The blood flow in the intestinal wall and mucosa of the control, sham and rhubarb-treated groups was significantly higher, while the sepsis group had relatively low blood flow. The L/P ratio in the intestinal tissue was larger in the sepsis group than in the other three groups. The microvascular area (MVA) in the sepsis group was smaller than in the control group, sham group or rhubarb group. Positive expression for CD31 was observed in the cytoplasm of vascular endothelial cells. The intestinal mucosal capillaries were reduced in septic rats as compared to the other three groups. HUVEC proliferation was enhanced by the rhubarb extract monomers at 1 ?mol/L, but suppressed at higher concentrations of 10 to 100 ?mol/L. These results suggest that pre-treatment with rhubarb prior to sepsis induction promotes the expansion of the intestinal mucosal capillaries, protects intestinal mucosal capillary endothelial cells and increases the number of functional intestinal capillaries.
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Ultra-pH-sensitive nanoprobe library with broad pH tunability and fluorescence emissions.
J. Am. Chem. Soc.
PUBLISHED: 07-29-2014
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pH is an important physiological parameter that plays a critical role in cellular and tissue homeostasis. Conventional small molecular pH sensors (e.g., fluorescein, Lysosensor) are limited by broad pH response and restricted fluorescent emissions. Previously, we reported the development of ultra-pH-sensitive (UPS) nanoprobes with sharp pH response using fluorophores with small Stokes shifts (<40 nm). In this study, we expand the UPS design to a library of nanoprobes with operator-predetermined pH transitions and wide fluorescent emissions (400-820 nm). A copolymer strategy was employed to fine tune the hydrophobicity of the ionizable hydrophobic block, which led to a desired transition pH based on standard curves. Interestingly, matching the hydrophobicity of the monomers was critical to achieve a sharp pH transition. To overcome the fluorophore limitations, we introduced copolymers conjugated with fluorescence quenchers (FQs). In the micelle state, the FQs effectively suppressed the emission of fluorophores regardless of their Stokes shifts and further increased the fluorescence activation ratios. As a proof of concept, we generated a library of 10 nanoprobes each encoded with a unique fluorophore. The nanoprobes cover the entire physiologic range of pH (4-7.4) with 0.3 pH increments. Each nanoprobe maintained a sharp pH transition (on/off < 0.25 pH) and high fluorescence activation ratio (>50-fold between on and off states). The UPS library provides a useful toolkit to study pH regulation in many pathophysiological indications (e.g., cancer, lysosome catabolism) as well as establishing tumor-activatable systems for cancer imaging and drug delivery.
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Isolation of benzoic and cinnamic acid derivatives from the grains of Sorghum bicolor and their inhibition of lipopolysaccharide-induced nitric oxide production in RAW 264.7 cells.
Food Chem
PUBLISHED: 07-15-2014
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Two new caffeoylglycerols, (hwanggeumchal A-B, 9-10), together with eight known derivatives (1-8) were isolated from the grains of Sorghum bicolor (L.) Moench var. hwanggeumchal. Their chemical structures were established mainly by 1D and 2D NMR techniques and MS data analysis. Amongst those, methyl 3,4-dihydroxybenzoate (2), 3,4,5-trihydroxycinnamate (3), methyl 3,4-dihydroxycinnamate (5), caffeoylglycolic acid methyl ester (7) and 1-O-caffeoylglycerol (8) displayed potential inhibitory effects against LPS-induced NO production in macrophage RAW264.7 cells with IC50 values of 11.9, 2.9, 27.1, 29.0 and 18.5?M, respectively. Furthermore, these compounds dose-dependently reduced the LPS-induced iNOS expression. In addition, pre-incubation of cells with compounds 2, 3 and 5 significantly suppressed LPS-induced COX-2 protein expression. SAR investigation revealed that compounds with a methyl ester (COOCH3) group possessed stronger activity. Our obtained data suggest that S. bicolor and its caffeoylglyceride-enrich extracts may be applied as supplemental and/or functional foods having a beneficial effect against inflammation.
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Serum-stabilized naked caspase-3 siRNA protects autotransplant kidneys in a porcine model.
Mol. Ther.
PUBLISHED: 06-03-2014
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The naked small interfering RNA (siRNA) of caspase-3, a key player in ischemia reperfusion injury, was effective in cold preserved and hemoreperfused kidneys, but not autotransplanted kidneys in our porcine models. Here, chemically modified serum stabilized caspase-3 siRNAs were further evaluated. The left kidney was retrieved and infused by University of Wisconsin solution with/without 0.3?mg caspase-3 or negative siRNA into the renal artery for 24-hour cold storage (CS). After an intravenous injection of 0.9?mg siRNA and right-uninephrectomy, the left kidney was autotransplanted for 2 weeks. The effectiveness of caspase-3 siRNA was confirmed by caspase-3 knockdown in the post-CS and/or post-transplant kidneys with reduced apoptosis and inflammation, while the functional caspase-3 siRNA in vivo was proved by detected caspase-3 mRNA degradation intermediates. HMGB1 protein was also decreased in the post-transplanted kidneys; correlated positively with renal IL-1? mRNA, but negatively with serum IL-10 or IL-4. The minimal off-target effects of caspase-3 siRNA were seen with favorable systemic responses. More importantly, renal function, associated with active caspase-3, HMGB1, apoptosis, inflammation, and tubulointerstitial damage, was improved by caspase-3 siRNA. Taken together, the 2-week autotransplanted kidneys were protected when caspase-3 siRNA administrated locally and systemically, which provides important evidence for future clinical trials.
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Divergent LIN28-mRNA associations result in translational suppression upon the initiation of differentiation.
Nucleic Acids Res.
PUBLISHED: 05-23-2014
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LIN28 function is fundamental to the activity and behavior of human embryonic stem cells (hESCs) and induced pluripotent stem cells. Its main roles in these cell types are the regulation of translational efficiency and let-7 miRNA maturation. However, LIN28-associated mRNA cargo shifting and resultant regulation of translational efficiency upon the initiation of differentiation remain unknown. An RNA-immunoprecipitation and microarray analysis protocol, eRIP, that has high specificity and sensitivity was developed to test endogenous LIN28-associated mRNA cargo shifting. A combined eRIP and polysome analysis of early stage differentiation of hESCs with two distinct differentiation cues revealed close similarities between the dynamics of LIN28 association and translational modulation of genes involved in the Wnt signaling, cell cycle, RNA metabolism and proteasomal pathways. Our data demonstrate that change in translational efficiency is a major contributor to early stages of differentiation of hESCs, in which LIN28 plays a central role. This implies that eRIP analysis of LIN28-associated RNA cargoes may be used for rapid functional quality control of pluripotent stem cells under manufacture for therapeutic applications.
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A method for reconstruction of vermilion tubercle.
Plast Reconstr Surg Glob Open
PUBLISHED: 05-01-2014
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This article reports on the bilateral lip mucosa flaps (BLMFs) for reconstruction of the vermilion tubercle of the corrected cleft lip deformity.
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A novel proteolysis-resistant cyclic helix B peptide ameliorates kidney ischemia reperfusion injury.
Biochim. Biophys. Acta
PUBLISHED: 04-12-2014
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Helix B surface peptide (HBSP), derived from erythropoietin, displays powerful tissue protection during kidney ischemia reperfusion (IR) injury without erythropoietic side effects. We employed cyclization strategy for the first time, and synthesized thioether-cyclized helix B peptide (CHBP) to improve metabolic stability and renoprotective effect. LC-MS/MS analysis was adopted to examine the stability of CHBP in vitro and in vivo. The renoprotective effect of CHBP in terms of renal function, apoptosis, inflammation, extracellular matrix deposition, and histological injury was also detected in vivo and in vitro. Antibody array and western blot were performed to analyze the signal pathway of involvement by CHBP in the IR model and renal tubular epithelial cells. In this study, thioether-cyclized peptide was significantly stable in vivo and in vitro. One dose of 8nmol/kg CHBP administered intraperitoneally at the onset of reperfusion improved renal protection compared with three doses of 8nmol/kg linear HBSP in a 48h murine IR model. In a one-week model, the one dose CHBP-treated group exhibited remarkably improved renal function over the IR group, and attenuated kidney injury, including reduced inflammation and apoptosis. Interestingly, we found that the phosphorylation of autophagy protein mTORC1 was dramatically reduced upon CHBP treatment. We also demonstrated that CHBP induced autophagy via inhibition of mTORC1 and activation of mTORC2, leading to renoprotective effects on IR. Our results indicate that the novel metabolically stable CHBP is a promising therapeutic medicine for kidney IR injury treatment.
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Transgenic expression of human cytoxic T-lymphocyte associated antigen4-Immunoglobulin (hCTLA4Ig) by porcine skin for xenogeneic skin grafting.
Transgenic Res.
PUBLISHED: 03-26-2014
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Porcine skin is frequently used as a substitute of human skin to cover large wounds in clinic practice of wound care. In our previous work, we found that transgenic expression of human cytoxicT-lymphocyte associated antigen4-immunoglobulin (hCTLA4Ig) in murine skin graft remarkably prolonged its survival in xenogeneic wounds without extensive immunosuppression in recipients, suggesting that transgenic hCTLA4Ig expression in skin graft may be an effective and safe method to prolong xenogeneic skin graft survival. In this work, using a transgene construct containing hCTLA4Ig coding sequence under the drive of human Keratine 14 (k14) promoter, hCTLA4Ig transgenic pigs were generated by somatic nuclear transfer. The derived transgenic pigs were healthy and exhibited no signs of susceptibility to infection. The hCTLA4Ig transgene was stably transmitted through germline over generations, and thereby a transgenic pig colony was established. In the derived transgenic pigs, hCTLA4Ig expression in skin was shown to be genetically stable over generations, and detected in heart, kidney and corneal as well as in skin. Transgenic hCTLA4Ig protein in pigs exhibited expected biological activity as it suppressed human lymphocyte proliferation in human mixed lymphocyte culture to extents comparable to those of commercially purchased purified hCTLA4Ig protein. In skin grafting from pigs to rats, transgenic porcine skin grafts exhibited remarkably prolonged survival compared to the wild-type skin grafts derived from the same pig strain (13.33 ± 3.64 vs. 6.25 ± 2.49 days, P < 0.01), further indicating that the transgenic hCTLA4Ig protein was biologically active and capable of extending porcine skin graft survival in xenogeneic wounds. The transgenic pigs generated in this work can be used as a reproducible resource to provide porcine skin grafts with extended survival for wound coverage, and also as donors to investigate the impacts of hCTLA4Ig on xenotransplantation of other organs (heart, kidney and corneal) due to the ectopic transgenic hCTLA4Ig expression.
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Entangling different-color photons via time-resolved measurement and active feed forward.
Phys. Rev. Lett.
PUBLISHED: 03-10-2014
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Entangling independent photons is not only of fundamental interest but also of crucial importance for quantum-information science. Two-photon interference is a major method for entangling independent identical photons. If two photons are different in color, perfect two-photon coalescence can no longer happen, which makes the entangling of different-color photons difficult to realize. In this Letter, by exploring and developing time-resolved measurement and active feed forward, we have entangled two independent photons of different colors for the first time. We find that entanglement with a varying form can be identified for different two-photon temporal modes through time-resolved measurement. By using active feed forward, we are able to convert the varying entanglement into uniform entanglement. Adopting these measures, we have successfully entangled two photons with a frequency separation 16 times larger than their linewidths. In addition to its fundamental interest, our work also provides an approach for solving the frequency-mismatch problem for future quantum networks.
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Complement C5a is detrimental to histological and functional locomotor recovery after spinal cord injury in mice.
Neurobiol. Dis.
PUBLISHED: 02-23-2014
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Based on the studies on the role of complements C3, C1q and factor B, we hypothesized that complement C5a is detrimental to locomotor recovery at the early stage of secondary injury after spinal cord injury (SCI). To test this hypothesis, we investigated the effect of inhibition of complement C5a receptor (C5aR) by using C5aR antagonist PMX53 (C5aRA) and deficiency of complement C5a receptor (C5aR-/- mice) on histological and locomotor recovery after SCI in mice. We demonstrated that the Basso Mouse Scale scores in the mice injected with C5aRA (C5aRA-mice) at 45min before and 24h after SCI and the C5aR-/- mice were markedly higher than those in the mice treated with saline (Saline-mice) and the C5aR+/+ mice respectively between 7 and 28days after SCI. Also, expression of TNF-? and IL-1? in C5aRA-mice was significantly lower than that in Saline-mice from 1 to 24h after SCI. In addition, the percentage of microglia/macrophage in C5aRA mice and C5aR-/- mice was significantly lower than those in their corresponding control groups from 1 to 14days after SCI. Furthermore, C5aRA mice and C5aR-/- mice had less GFAP expression in the injured spinal cord epicenter as compared to Saline mice and C5aR+/+ mice at day 28 after SCI. These findings provided evidence that inhibition or deficiency of C5aR could significantly improve histological and functional locomotor recovery after SCI in mice.
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Increased peripheral and local soluble FGL2 in the recovery of renal ischemia reperfusion injury in a porcine kidney auto-transplantation model.
J Transl Med
PUBLISHED: 02-19-2014
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Regulatory T cells (Treg) protect kidney against ischemia reperfusion (IR) injury via suppressing innate immunity, but the mechanism has not been fully clarified. Soluble fibrinogen-like protein 2 (sFGL2), a novel effector of Treg, may affect apoptosis and inflammation. This study investigated the role of sFGL2 in renal IR injury in a porcine kidney auto-transplantation model.
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Quantitative analysis of four types of primary glomeropathy by application of a decision forest to ultrasonic and laboratory characteristics.
Ultrasound Med Biol
PUBLISHED: 02-15-2014
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The aim of this study was to apply a decision forest to analysis of the ultrasound characteristics and laboratory test indices of four types of primary glomerulopathy, and quantitative analysis of the four pathologic types using a combination of these two methods. The decision trees were derived from 41 clinical indices and 5 characteristic sonographic indices obtained for the left kidney. Fifty-six patients who had undergone ultrasound-guided renal biopsy were reviewed retrospectively, and on pathologic examination, the patients were diagnosed with primary glomerulopathy, which includes mesangial proliferative glomerulonephritis, membranous nephropathy, immunoglobulin A nephropathy and minimal change disease. In this study, eight characteristic indicators were correlated with pathologic type in the 56 cases of primary glomerulopathy. The order calculated by decision forests, from high to low, is proteinuria, length of kidney, serum creatinine, plasma albumin, area of kidney, total protein, thickness of renal parenchyma, 24-h urine protein. The glomerulopathy with the highest ++++ proteinuria is membranous nephropathy, which accounts for 39.2% (22/56) of the total sample; this was followed by minimal change disease, mesangial proliferative glomerulonephritis and immunoglobulin A nephropathy. On the basis of our analysis of 41 clinical indices, the key indices for quantitative analysis of primary glomerulonephritis are laboratory tests, and these include urine protein, serum creatinine, plasma albumin, total serum protein and 24-h urine protein. The three key sonographic features are measurement indices: renal length, renal area and renal parenchymal thickness. From the eight characteristic indicators, we observed that with respect to severity (from most severe to least severe), the four types of glomerulopathy are membranous nephropathy, minimal change disease, mesangial proliferative glomerulonephritis and immunoglobulin A nephropathy.
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Dosimetric evaluation of integrated IMRT treatment of the chest wall and supraclavicular region for breast cancer after modified radical mastectomy.
Med Dosim
PUBLISHED: 02-04-2014
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To investigate the dosimetric characteristics of irradiation of the chest wall and supraclavicular region as an integrated volume with intensity-modulated radiation therapy (IMRT) after modified radical mastectomy. This study included 246 patients who received modified radical mastectomy. The patients were scanned with computed tomography, and the chest wall (with or without the internal mammary lymph nodes) and supraclavicular region were delineated. For 143 patients, the chest wall and supraclavicular region were combined as an integrated planning volume and treated with IMRT. For 103 patients, conventional treatments were employed with 2 tangential fields for the chest wall, abutting a mixed field of 6-MV x-rays (16Gy) and 9-MeV electrons (34Gy) for the upper supraclavicular region. The common prescription dose was 50Gy/25Fx/5W to 90% of the target volume. The dosimetric characteristics of the chest wall, the supraclavicular region, and normal organs were compared. For the chest wall target, compared with conventional treatments, the integrated IMRT plans lowered the maximum dose, increased the minimum dose, and resulted in better conformity and uniformity of the target volume. There was an increase in minimum, average, and 95% prescription dose for the integrated IMRT plans in the supraclavicular region, and conformity and uniformity were improved. The V30 of the ipsilateral lung and V10, V30, and mean dose of the heart on the integrated IMRT plans were lower than those of the conventional plans. The V5 and V10 of the ipsilateral lung and V5 of the heart were higher on the integrated IMRT plans (p < 0.05) than on conventional plans. Without an increase in the radiation dose to organs at risk, the integrated IMRT treatment plans improved the dose distribution of the supraclavicular region and showed better dose conformity and uniformity of the integrated target volume of the chest wall and supraclavicular region.
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Embryology training for Reproductive Endocrine fellows in the clinical human embryology laboratory.
J. Assist. Reprod. Genet.
PUBLISHED: 02-03-2014
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To determine if comprehensive embryology training for clinical Reproductive Endocrinology fellows could be completed to a level of proficiency equivalent to that of experienced embryologists.
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[Biomarkers in acute lung injury].
Zhongguo Dang Dai Er Ke Za Zhi
PUBLISHED: 01-28-2014
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Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) is characterized by non-cardiogenic, acute and progressive respiratory failure mediated by a variety of injurious stimuli. ALI can progress to ARDS if an effective management is not taken. The mortality rate remains high due to the complex pathogenesis and ineffective management of ARDS. At present, effective treatment methods for ALI are not available and thus it is important to study the pathogenesis and early diagnosis of ALI. This article reviews some of the biomarkers associated with ALI, with a focus on early diagnosis and future studies.
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Antithrombotic and antidiabetic flavonoid glycosides from the grains of Sorghum bicolor (L.) Moench var. hwanggeumchal.
Arch. Pharm. Res.
PUBLISHED: 01-16-2014
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A phytochemical study of the grains of S. bicolor, resulting in the isolation of twelve flavonoid glycosides 1-12. Their chemical structures were elucidated on the basis of spectroscopic (1D and 2D NMR) and MS data analyses. All compounds were tested on thrombin time (TT) assay and ?-glucosidase assay in order to assess their inhibitory effects on blood coagulation and ?-glucosidase enzyme. At the concentration of 500 ?g/mL, compounds 3, 4, 7 and 10 possessed the potential effects on blood coagulation with inhibitory percentage of 197, 152, 120 and 158 %, respectively, whereas aspirin, which used as a positive control, indicated 181 and 138 % inhibition at 500 and 375 ?g/mL, respectively. Furthermore, compounds 3, 4, 7, 9 and 10 also displayed strong inhibitory effects on ?-glucosidase enzyme, with 85.2, 55.7, 43.9, 52.7 and 65.2 % inhibition at 100 ?g/mL, respectively, whereas acarbose, as a positive control, possessed only 38.7 % at the same concentration. Taken together, our data suggest that S. bicolor and its flavonoid-enrich extracts could be considered as supplemental and or functional foods having beneficial effects against blood coagulation-induced ischemia, possibly thromboembolism disease, as well as diabetes.
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The regulatory T cell effector soluble fibrinogen-like protein 2 induces tubular epithelial cell apoptosis in renal transplantation.
Exp. Biol. Med. (Maywood)
PUBLISHED: 01-10-2014
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Acute rejection (AR) hinders renal allograft survival. Tubular epithelial cell (TEC) apoptosis contributes to premature graft loss in AR, while the mechanism remains unclear. Soluble fibrinogen-like protein 2 (sFGL2), a novel effector of regulatory T cells (Treg), induces apoptosis to mediate tissue injury. We previously found that serum sFGL2 significantly increased in renal allograft rejection patients. In this study, the role of sFGL2 in AR was further investigated both in vivo and in vitro. The serum level of sFGL2 and the percentage of CD4(+)CD25(+)Foxp3(+) Treg in the peripheral blood were measured in renal allograft recipients with AR or stable renal function (n = 30 per group). The human TEC was stimulated with sFGL2, tumor necrosis factor (TNF)-?, or phosphate buffered saline and investigated for apoptosis in vitro. Apoptosis-associated genes expression in TEC was further assessed. Approval for this study was obtained from the Ethics Committee of Fudan University. Our results showed that the serum level of sFGL2, correlated with Treg in the peripheral blood, was significantly increased in the AR patients. In vitro, sFGL2 remarkably induced TEC apoptosis, with a significant up-regulation of proapoptotic genes, including CASP-3, CASP-8, CASP-9, CASP-10, TRADD, TNFSF10, FADD, FAS, FASLG, BAK1, BAD, BAX, and NF-KB1. However, no significant changes were observed in the expression of antiapoptotic genes, including CARD-18, NAIP, BCL2, IKBKB, and TBK1. Therefore, sFGL2, an effector of Treg, induces TEC apoptosis. Our study suggests that sFGL2 is a potential mediator in the pathogenesis of allograft rejection and provides novel insights into the role of Treg in AR.
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Rare de novo copy number variants in patients with congenital pulmonary atresia.
PLoS ONE
PUBLISHED: 01-01-2014
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Ongoing studies using genomic microarrays and next-generation sequencing have demonstrated that the genetic contributions to cardiovascular diseases have been significantly ignored in the past. The aim of this study was to identify rare copy number variants in individuals with congenital pulmonary atresia (PA).
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Hypoxia Induces autophagic cell death through hypoxia-inducible factor 1? in microglia.
PLoS ONE
PUBLISHED: 01-01-2014
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As phagocytic cells of central nervous system, excessive activation or cell death of microglia is involved in a lot of nervous system injury and degenerative disease, such as stroke, epilepsy, Parkinson's disease, Alzheimer's disease. Accumulating evidence indicates that hypoxia upregulates HIF-1? expression leading to cell death of microglia. However, the exact mechanism of cell death induced by hypoxia in microglia is not clear. In the current study, we showed that hypoxia induced cell death and autophagy in microglia. The suppression of autophagy using either pharmacologic inhibitors (3-methyladenine, bafilomycin A1) or RNA interference in essential autophagy genes (BECN1 and ATG5) decreased the cell death induced by hypoxia in microglia cells. Moreover, the suppression of HIF-1? using either pharmacologic inhibitors (3-MA, Baf A1) or RNA interference decreased the microglia death and autophagy in vitro. Taken together, these data indicate that hypoxia contributes to autophagic cell death of microglia through HIF-1?, and provide novel therapeutic interventions for cerebral hypoxic diseases associated with microglia activation.
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Rare copy number variations containing genes involved in RASopathies: deletion of SHOC2 and duplication of PTPN11.
Mol Cytogenet
PUBLISHED: 01-01-2014
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RASopathies are a group of disorders related to Noonan syndrome that with dysregulated RAS-mitogen-activated protein kinase (MAPK) signaling pathway. Noonan syndrome (NS, OMIM# 163950) is a both phenotypically and genotypically variable disorder. We and other researchers have demonstrated that copy number variations underlie a small percentage of patients with RASopathies.
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[Application of dexmedetomidine for brain nuclei lesion of patients with Parkinsons disease].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 12-24-2013
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To observe the sedative and analgesic effects of dexmedetomidine (Dex) and its influence on respiration and blood pressure, evaluate electrophysiological monitoring and explore the optimal dose of Dex for brain nuclei lesion in Parkinsons disease (PD) patients.
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[Effects of elevated O3 concentration and UV-B radiation on the chlorophyll content and active oxygen metabolism of soybean leaves].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 09-11-2013
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Taking the soybean (Glycine max) cultivar Tiefeng 29 as test material, and by using open-top chamber, this paper studied the effects of elevated O3 concentration and UV-B radiation on the leaf chlorophyll content, lipid peroxidation, reactive oxygen species (ROS) production rate, anti-oxidation enzymes activities, and the grain yield. During the growth period of soybean, as compared with the control, the leaf Chl a, Chl b and Chl (a+b) contents under the stresses of O3 and UV-B had a decreasing trend, the relative electrical conductivity, malondialdehyde content, superoxide anion (O2) production rate, and hydrogen peroxide (H2O2) content increased, and the activities of superoxide dismutase, peroxidase and catalase as well as the grain yield decreased. O3+ UV stress aggravated the leaf membrane lipid peroxidation, promoted the ROS production, and decreased the plant antioxidant capacity and leaf chlorophyll content. The negative effects of O3 stress on soybean leaves were more close to the impacts of O3+UV stress, suggesting that O3 might play an important role in the combined stress.
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Quantitative and pattern recognition analyses of magnoflorine, spinosin, 6-feruloyl spinosin and jujuboside A by HPLC in Zizyphi Semen.
Arch. Pharm. Res.
PUBLISHED: 08-13-2013
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Two rapid and simple HPLC methods with UV detector to determine three main compounds (magnoflorine, spinosin and 6-feruloyl spinosin) and evaporative light scattering detector (ELSD) to determine jujuboside A were developed for the chemical analyses of Zizyphi Semen. Magnoflorine, spinosin, and 6-feruloyl spinosin were separated with an YMC Jsphere ODS-H80 column (250 mm × 4.6 mm, 4 ?m) by the gradient elution followed by the isocratic elution using methanol with 0.1 % formic acid and water with 0.1 % formic acid as the mobile phase. The flow rate was 1.0 mL/min. Jujuboside A was separated by HPLC-ELSD with YoungJinBioChrom Aegispak C18-L column (250 mm × 4.6 mm, 5 ?m) column in a gradient elution using methanol with 0.1 % formic acid (A) and water with 0.1 % formic acid as the mobile phase. These two methods were fully validated with respect to linearity, precision, accuracy, stability, and robustness. These HPLC methods were applied successfully to quantify four compounds in a Zizyphi Semen extract. The HPLC analytical methods were validated for pattern recognition analysis by repeated analysis of 91 seed samples corresponding to 48 Zizyphus jujuba var. spinosa (J01-J48) and 43 Zizyphus mauritiana (M01-M43). The results indicate that these methods are suitable for a quality evaluation of Zizyphi Semen.
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Innate immunity activation involved in unprotected porcine auto-transplant kidneys preserved by naked caspase-3 siRNA.
J Transl Med
PUBLISHED: 06-13-2013
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The naked caspase-3 small interfering RNA (siRNA) infused into the renal artery during cold preservation was effective, but did not protect auto-transplant porcine kidneys with increased inflammation and apoptosis in our previous study. The mechanisms involved, in particular, whether siRNA or complementary systemic feedback eliciting innate immune responses are worthy to be further investigated.
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A novel planarization method based on photoinduced confined chemical etching.
Chem. Commun. (Camb.)
PUBLISHED: 06-13-2013
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A photoinduced confined chemical etching system based on TiO2 nanotube arrays is developed for the planarization of the copper surface, which is proved to be a prospective stress-free chemical planarization method for metals and semiconductors.
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Intraoperative device closure of subaortic ventricular septal defects.
J Card Surg
PUBLISHED: 06-11-2013
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To evaluate the safety and the indication for percardiac device closure of subaortic ventricular septal defects (VSDs) under guidance of transesophageal echocardiography.
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Characterization and bioactivity of polysaccharides obtained from pine cones of Pinus koraiensis by graded ethanol precipitation.
Molecules
PUBLISHED: 06-08-2013
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Pinus koraiensis polysaccharides (PKP) were extracted by hot water from P. koraiensis pine cones. Five polysaccharide fractions named PKP-A, PKP-B, PKP-C, PKP-D and PKP-E were successfully separated at final ethanol concentrations of 30%, 50%, 60%, 70% and 80%, respectively. HPLC, FT-IR, GC-MS and automatic amino-acid analysis were applied to investigate their chemical characteristics. Monosaccharide component analysis indicated that the five fractions were all composed of D-ribose, L-rhamnose, L-arabinose, D-xylose, D-mannose, D-glucose and D-galactose, but their molar ratios were quite different. HPLC results revealed that the polysaccharides precipitated by higher concentrations of ethanol solution had lower molecular masses. Moreover, the antioxidant activities of the five fractions were studied on the basis of hydroxyl radical and ABTS radical scavenging tests. The five graded polysaccharide fractions exhibited good inhibitory power, and MTT tests in vitro showed the IC50 of PKP-A and PKP-E were 1,072.5 and 2,070.0 ?g · mL-1, respectively. These results demonstrated that the PKP could be a potential source of natural antioxidants or dietary supplements.
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[Melissopalynology and trophic niche of Apis cerana ceraca and Apis mellifera ligustica in Yunnan Province of Southwest China].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 05-31-2013
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In 2010 and 2011, the honey samples of Apis cerana cerana and A. mellifera ligustica were collected from Kunming and Mengzi of Yunnan Province, respectively, aimed to analyze the melissopalynology and tropic niche of the two bee species. The absolute pollen concentration of the honey of A. cerana cerana was 1.55 x 10(4) ind x g(-1), being significantly higher than that (1.01 x 10(4) ind x g(-1)) of A. mellifera ligustica, and the number of nectar plant species collected by A. cerana cerana was 12.9, also significantly higher than that (7.7) collected by A. mellifera ligustica, indicating that A. cerana cerana could utilize more nectar plants, while A. mellifera ligustica had stronger selectivity to the nectar plants. The trophic niche breadth of A. cerana cerana was 0.35, which was significantly higher than that (0.23) of A. mellifera ligustica. The trophic niche overlap index between the two bee species was 0.71, and the interspecific competition index was 0.93, suggesting that the food competition between A. cerana cerana and A. mellifera ligustica was fierce.
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A microporous metal-organic framework containing an exceptional four-connecting 4(2)6(4) topology and a combined effect for highly selective adsorption of CO2 over N2.
Dalton Trans
PUBLISHED: 05-17-2013
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Reported here is a new microporous metal-organic framework, namely [Zn(2)(L)(btc)(Hbtc)] [NH(2)(CH(3))(2)]·(DMF)(2)(H(2)O)(4) (1), which is synthesized solvo(hydro)thermally by the self-assembly of Zn(NO(3))(2), N(4),N(4)-di(pyridin-3-yl)-[1,1-biphenyl]-4,4-dicarboxamide (L) and 1,3,5-benzenetricarboxylate acid (H(3)btc). Its topology can be described as a four-connecting 4(2)6(4) matrix containing both tetrahedral metal and ligand nodes. Interestingly, such a matrix has the same topology symbol as that observed in the well known sodalite (SOD) net, but the td10 of 434 is different from the td10 of 791 for the SOD net, indicative of an exceptional four-connecting 4(2)6(4) net. Another outstanding point is the highly selective adsorption of CO(2) over N(2), possibly contributed by a combined effect from the charged skeleton, the existence of functional groups of -CONH- and -COOH in 1.
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Time--temperature indicator for perishable products based on kinetically programmable Ag overgrowth on Au nanorods.
ACS Nano
PUBLISHED: 05-01-2013
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Food safety is a constant concern for humans. Besides adulteration and contamination, another major threat comes from the spontaneous spoilage of perishable products, which is basically inevitable and highly dependent on the temperature history during the custody chain. For advanced quality control and assessment, time-temperature indicators (TTIs) can be deployed to document the temperature history. However, the use of TTIs is currently limited by either relatively high cost or poor programmability. Here we describe a general, kinetically programmable, and cost-efficient TTI protocol constructed from plasmonic nanocrystals. We present proof-of-principle demonstrations that our TTI can be specifically tailored and thus used to track perishables, dynamically mimic the deteriorative processes therein, and indicate product quality through sharp-contrast multicolor changes. The flexible programmability of our TTI, combined with its substantially low cost and low toxicity, promises a general applicability to each single packaged item of a plethora of perishable products.
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Common underlying diseases do not contribute in determining the causes of sudden unexplained death.
Chin. Med. J.
PUBLISHED: 03-16-2013
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Underlying diseases have a statistically significant positive correlation to sudden death. However, sudden unexplained death (SUD) is different from sudden death, as there is no clinical evidence to support the sudden death due to the original underlying disease, nor a lethal pathological basis to be found during autopsy. In addition, SUD are more common in young, previously healthy individuals, usually without any signs of disease, with no positive lesions found after autopsy. Therefore, a causal relationship between SUD and the underlying disease needs to be further explored. This study aimed to explore the role that common underlying diseases play in patients with SUD and to reveal the correlation between them.
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Determination of free amino acids and 18 elements in freeze-dried strawberry and blueberry fruit using an Amino Acid Analyzer and ICP-MS with micro-wave digestion.
Food Chem
PUBLISHED: 03-15-2013
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The objective of this study was to investigate the level of 18 trace elements of two freeze-dried samples from the Blueberry (Vaccinium corymbosum) and the Strawberry (Fragaria × Ananassa). The total free amino acid composition in the blueberry and strawberry was determined by an Amino Acid Analyzer. Eleven free amino acids were found in both berries. The trace elements in each dried fruit sample were determined by ICP-MS with microwave digestion. The linearity range of the standard curves was 0-1250.0 ?g L(-1) (Mg, P, K, Ca),while in all cases, except for B, Na, Al, Cr, Mn, Fe, Ni, Cu, Zn, Se, Cd, Pb, Ge and As, which was 125.0 ?g mL(-1), all related coefficients were above 0.9999; recovery was in the range of 79.0-106.8%. Minor concentrations of nutritional elements were found in each freeze-dried berry. In sum, the toxic trace element analysis found the content of toxic trace elements in each freeze-dried berry sample was safe for human consumption and that the overall quality of the blueberry surpassed that of the strawberry. The results certify that the two freeze-dried berries have potential for human consumption in value-added products and have a certain theoretical and practical significance.
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Helix B surface peptide administered after insult of ischemia reperfusion improved renal function, structure and apoptosis through beta common receptor/erythropoietin receptor and PI3K/Akt pathway in a murine model.
Exp. Biol. Med. (Maywood)
PUBLISHED: 03-13-2013
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Erythropoietin (EPO) has been well recognized as a tissue protective agent by inhibiting apoptosis and inflammation. The tissue protective effect of EPO, however, only occurs at a high dosage, which may elicit severe side-effects at the meantime. Helix B surface peptide (HBSP), a novel peptide derived from the non-erythropoietic helix B of EPO, plays a specific role in tissue protection. We investigated effects of HBSP and the expression of its heterodimeric receptor, beta common receptor (?cR)/EPO receptor ( ), in a murine renal ischemia reperfusion (IR) injury model. HBSP significantly ameliorated renal dysfunction and tissue damage, decreased apoptotic cells in the kidney and reduced activation of caspase-9 and -3. The ?cR/EPOR in the kidney was up-regulated by IR, but down-regulated by HBSP. Further investigation revealed that the expression and phosphorylation of Akt was dramatically enhanced by HBSP, but strongly reversed by wortmannin, the PI3K inhibitor. Wortmannin intervention improved ?cR/EPOR expression, promoted caspase-9 and -3 activation, and increased active caspase-3 positive cells, while renal function and structure, and apoptotic cell counts scarcely changed. This result indicates a significant contribution of PI3K/Akt signaling pathway in the renoprotection of HBSP. The therapeutic effects of HBSP in this study suggest that HBSP could be a better candidate for renal protection.
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A nanoparticle-based strategy for the imaging of a broad range of tumours by nonlinear amplification of microenvironment signals.
Nat Mater
PUBLISHED: 03-07-2013
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Stimuli-responsive nanomaterials are increasingly important in a variety of applications such as biosensing, molecular imaging, drug delivery and tissue engineering. For cancer detection, a paramount challenge still exists in the search for methods that can illuminate tumours universally regardless of their genotypes and phenotypes. Here we capitalized on the acidic, angiogenic tumour microenvironment to achieve the detection of tumour tissues in a wide variety of mouse cancer models. This was accomplished using ultra pH-sensitive fluorescent nanoprobes that have tunable, exponential fluorescence activation on encountering subtle, physiologically relevant pH transitions. These nanoprobes were silent in the circulation, and then strongly activated (>300-fold) in response to the neovasculature or to the low extracellular pH in tumours. Thus, we have established non-toxic, fluorescent nanoreporters that can nonlinearly amplify tumour microenvironmental signals, permitting the identification of tumour tissue independently of histological type or driver mutation, and detection of acute treatment responses much more rapidly than conventional imaging approaches.
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Rac1 modulates the vitreous-induced plasticity of mesenchymal movement in retinal pigment epithelial cells.
Clin. Experiment. Ophthalmol.
PUBLISHED: 03-03-2013
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The vitreous has been shown to induce epithelial-mesenchymal transdifferentiation because it induces fibroblast-like morphology, enhanced migration and invasion in retinal pigment epithelial cells in proliferative vitreoretinopathy. Rac1 is the principal mediator of cell migration. In the current study, the relationship between Rac1 and cell migration, and invasion in vitreous-transformed retinal pigment epithelial cells was investigated using NSC23766, a specific inhibitor of Rac guanosine-5-triphosphatase activity, and the involvement of a Rac1 guanosine-5-triphosphatase-dependent pathway was detected.
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Comprehensive chromosome screening alters traditional morphology-based embryo selection: a prospective study of 100 consecutive cycles of planned fresh euploid blastocyst transfer.
Fertil. Steril.
PUBLISHED: 02-26-2013
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To determine how often trophectoderm biopsy and rapid, real-time quantitative polymerase chain reaction (PCR)-based comprehensive chromosome screening (CCS) alters clinical management by resulting in the transfer of a different embryo than would have been chosen by traditional day 5 morphology-based criteria.
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Lamin B1 fluctuations have differential effects on cellular proliferation and senescence.
J. Cell Biol.
PUBLISHED: 02-25-2013
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The nuclear lamina consists of A- and B-type lamins. Mutations in LMNA cause many human diseases, including progeria, a premature aging syndrome, whereas LMNB1 duplication causes adult-onset autosomal dominant leukodystrophy (ADLD). LMNB1 is reduced in cells from progeria patients, but the significance of this reduction is unclear. In this paper, we show that LMNB1 protein levels decline in senescent human dermal fibroblasts and keratinocytes, mediated by reduced transcription and inhibition of LMNB1 messenger ribonucleic acid (RNA) translation by miRNA-23a. This reduction is also observed in chronologically aged human skin tissue. To determine whether altered LMNB1 levels cause senescence, we either increased or reduced LMNB1. Both LMNB1 depletion and overexpression inhibited proliferation, but only LMNB1 overexpression induced senescence, which was prevented by telomerase expression or inactivation of p53. This phenotype was exacerbated by a simultaneous reduction of LMNA/C. Our results demonstrate that altering LMNB1 levels inhibits proliferation and are relevant to understanding the molecular pathology of ADLD.
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A pilot trial of the iPad tablet computer as a portable device for visual acuity testing.
J Telemed Telecare
PUBLISHED: 02-22-2013
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We evaluated the accuracy of an app for the iPad tablet computer (Eye Chart Pro) as a portable method of visual acuity (VA) testing. A total of 120 consecutive patients (240 eyes) underwent visual acuity test with an iPad 2 and a conventional light-box chart. The logMAR VA results from the iPad were significantly higher than those from the light-box (P < 0.001). Bland-Altman analysis revealed a mean difference (bias) of 0.02 logMAR units between the VA results from the iPad chart and the light-box chart, with 95% limits of agreement of -0.14 to 0.19. Two groups of patients were defined: in Group 1 there were 182 eyes with VA better than 0.1 according to the light-box VA test. The median logMAR VA by the iPad was 0.54 and by the light-box chart it was 0.52; there was no significant difference between them (P = 0.69). In Group 2 there were 58 eyes with VA equal to or worse than 0.1 according to the light-box VA test. The median logMAR VA by the iPad was 1.26 and was 1.10 by the light box; the result from the iPad was significantly lower (P < 0.001). The Eye Chart Pro app installed on the iPad is reliable for VA testing only when the Snellen VA is better than 0.1 (20/200).
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Cleavage-stage biopsy significantly impairs human embryonic implantation potential while blastocyst biopsy does not: a randomized and paired clinical trial.
Fertil. Steril.
PUBLISHED: 02-17-2013
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To determine if cleavage- or blastocyst-stage embryo biopsy affects reproductive competence.
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Quantitative determination and pattern recognition analyses of bioactive marker compounds from Dipsaci Radix by HPLC.
Arch. Pharm. Res.
PUBLISHED: 02-07-2013
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In this study, quantitative and pattern recognition analyses were developed using HPLC/UV for the quality evaluation of Dipsaci Radix. For quantitative analysis, five major bioactive compounds were assessed. The separation conditions employed for HPLC/UV were optimized using ODS C18 column (250 × 4.6 mm, 5 ?m) with a gradient of acetonitrile and water as the mobile phase at a flow rate of 1.0 mL/min and a detection wavelength of 212 nm. These methods were fully validated with respect to linearity, accuracy, precision, recovery, and robustness. The HPLC/UV method was applied successfully to the quantification of five major compounds in the extract of Dipsaci Radix. The HPLC analytical method for pattern recognition analysis was validated by repeated analysis of 17 Dipsaci Radix and four Phlomidis Radix samples. The results indicate that the established HPLC/UV method is suitable for quantitative analysis.
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Shenfu injection attenuates neonatal hypoxic-ischemic brain damage in rat.
Neurol. Sci.
PUBLISHED: 01-24-2013
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Perinatal hypoxia-ischemia remains the most important cause of brain injury in the newborn. However, there is still no effective cure for neonatal hypoxic-ischemic brain damage (HIBD). In the present study, we aimed to examine the neuroprotective effects of Shenfu injection (SFI) on HIBD of neonatal rat. Sprague-Dawley rats were divided randomly into three groups (n = 8): S group: the rats were sham operated; C group: the rats were operated for HIBD modeling and received intraperitoneal injection of saline; SFI group: the rats were operated for HIBD modeling and received intraperitoneal injection of SFI (10 ml/kg days) for 7 days. Flow cytometry analysis showed that apoptosis rate of neuron in hippocampal CAI region in SFI group was significantly less than in NC group at 3 and 7 days after HI insult (P < 0.05). Immunohistochemical staining demonstrated that Bcl-2 expression was markedly higher while Bax expression was significantly lower in SFI group than in the C group at 24, 72 h and 7 days after HI insult (P < 0.05). Our findings suggest that SFI exhibits neuroprotective effects for neonatal hypoxic-ischemic brain injury by preventing neuron apoptosis and has potential to be used in the clinical for the treatment of perinatal hypoxia-ischemia.
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Quantitative analysis of betaine in Lycii Fructus by HILIC-ELSD.
Arch. Pharm. Res.
PUBLISHED: 01-23-2013
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A rapid and simple high-performance liquid chromatography (HPLC) method with evaporative light scattering detection (ELSD) was developed for the determination of betaine from Lycii Fructus. Betaine was separated with an Atlantis hydrophilic interaction liquid chromatography silica column (4.6 × 150 mm, 5 ?m, 100 Å) by isocratic elution using 30 mM ammonium acetate buffer and acetonitrile (20:80, v/v %) as the mobile phase. The flow rate was 1.0 mL/min, and the temperature for the spray chamber and drift tube was set at 30 and 50 °C, respectively. The method was fully validated with respect to linearity, precision, accuracy, stability and robustness. The HPLC/ELSD method was applied successfully to the quantification of betaine in the extract of Lycii Fructus. The HPLC analytical method for pattern recognition analysis was validated by repeated analysis of twenty-six L. barbarum L. from China (BC01-BC26), 3 L. barbarum L. (BJ27-BJ29) from Japan, 12 L. chinense Miller from China (CC30-CC41) and 51 L. chinense Miller samples (CK42-CK92) from Korea. The results indicate that the established HPLC/ELSD method is suitable for quality evaluation of Lycii Fructus.
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Soluble FGL2 induced by tumor necrosis factor-? and interferon-? in CD4+ T cells through MAPK pathway in human renal allograft acute rejection.
J. Surg. Res.
PUBLISHED: 01-19-2013
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Acute rejection (AR), initiated by alloreactive CD4(+) T cells, hampers allograft survival. Soluble fibrinogen-like protein 2 (sFGL2) is a novel effector of CD4(+) T cells. We previously found that serum sFGL2 significantly increased in renal allograft recipients with AR. In this study, sFGL2 secretion by CD4(+) T cells and its mechanism were further explored both in vivo and in vitro.
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A leveling method based on current feedback mode of scanning electrochemical microscopy.
Anal. Chem.
PUBLISHED: 01-17-2013
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Substrate leveling is an essential but neglected instrumental technique of scanning electrochemical microscopy (SECM). In this technical note, we provide an effective substrate leveling method based on the current feedback mode of SECM. By using an air-bearing rotary stage as the supporter of an electrolytic cell, the current feedback presents a periodic waveform signal, which can be used to characterize the levelness of the substrate. Tuning the adjusting screws of the tilt stage, substrate leveling can be completed in minutes by observing the decreased current amplitude. The obtained high-quality SECM feedback curves and images prove that this leveling technique is valuable in not only SECM studies but also electrochemical machining.
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Systemic blockade of dopamine D2-like receptors increases high-voltage spindles in the globus pallidus and motor cortex of freely moving rats.
PLoS ONE
PUBLISHED: 01-01-2013
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High-voltage spindles (HVSs) have been reported to appear spontaneously and widely in the cortical-basal ganglia networks of rats. Our previous study showed that dopamine depletion can significantly increase the power and coherence of HVSs in the globus pallidus (GP) and motor cortex of freely moving rats. However, it is unclear whether dopamine regulates HVS activity by acting on dopamine D?-like receptors or D?-like receptors. We employed local-field potential and electrocorticogram methods to simultaneously record the oscillatory activities in the GP and primary motor cortex (M1) in freely moving rats following systemic administration of dopamine receptor antagonists or saline. The results showed that the dopamine D?-like receptor antagonists, raclopride and haloperidol, significantly increased the number and duration of HVSs, and the relative power associated with HVS activity in the GP and M1 cortex. Coherence values for HVS activity between the GP and M1 cortex area were also significantly increased by dopamine D?-like receptor antagonists. On the contrary, the selective dopamine D?-like receptor antagonist, SCH23390, had no significant effect on the number, duration, or relative power of HVSs, or HVS-related coherence between M1 and GP. In conclusion, dopamine D?-like receptors, but not D?-like receptors, were involved in HVS regulation. This supports the important role of dopamine D?-like receptors in the regulation of HVSs. An siRNA knock-down experiment on the striatum confirmed our conclusion.
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Genome-wide identification of bone metastasis-related microRNAs in lung adenocarcinoma by high-throughput sequencing.
PLoS ONE
PUBLISHED: 01-01-2013
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MicroRNAs (miRNAs) are a class of small noncoding RNAs that regulate gene expression at the post-transcriptional level. They participate in a wide variety of biological processes, including apoptosis, proliferation and metastasis. The aberrant expression of miRNAs has been found to play an important role in many cancers.
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Fabrication of magnetic-antimicrobial-fluorescent multifunctional hybrid microspheres and their properties.
Int J Mol Sci
PUBLISHED: 01-01-2013
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Novel magnetic-antimicrobial-fluorescent multifunctional hybrid microspheres with well-defined nanostructure were synthesized by the aid of a poly(glycidyl methacrylate) (PGMA) template. The hybrid microspheres were fully characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR), X-ray diffraction (XRD) and digital fluorescence microscope. The as-synthesized microspheres PGMA, amino-modified PGMA (NH2-PGMA) and magnetic PGMA (M-PGMA) have a spherical shape with a smooth surface and fine monodispersity. M-PGMA microspheres are super-paramagnetic, and their saturated magnetic field is 4.608 emu·g-1, which made M-PGMA efficiently separable from aqueous solution by an external magnetic field. After poly(haxemethylene guanidine hydrochloride) (PHGH) functionalization, the resultant microspheres exhibit excellent antibacterial performance against both Gram-positive and Gram-negative bacteria. The fluorescence feature originating from the quantum dot CdTe endowed the hybrid microspheres with biological functions, such as targeted localization and biological monitoring functions. Combination of magnetism, antibiosis and fluorescence into one single hybrid microsphere opens up the possibility of the extensive study of multifunctional materials and widens the potential applications.
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[Cloning and expression of human interleukin-32 and studies on its bioactivity].
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi
PUBLISHED: 12-14-2011
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To clone human interleukin-32(hIL-32) gene and express it in E.coli efficiently.
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The application of single-crystal-to-single-crystal transformation towards adjustable SMM properties.
Chem. Commun. (Camb.)
PUBLISHED: 12-07-2011
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Reversible single-crystal-to-single-crystal transformation (SCSC) was for the first time observed between 4f-based molecular magnets.
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Huge Casimir effect at finite temperature in electromagnetic Rindler space.
Opt Lett
PUBLISHED: 12-06-2011
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We investigate the Casimir effect at a finite temperature in the electromagnetic Rindler space, and we find that the Casimir energy is proportional to T(4)/d(2) in the high-temperature limit, where T ? 27 °C is the temperature and d ? 100 nm is a small cutoff. We propose to make metamaterials to mimic the Rindler space and measure the predicted Casimir effect. Because the parameters of metamaterials we proposed are quite simple, this experiment would be easily implemented in the laboratory.
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[Expression of erythropoietin and its receptor in the brain of newborn rats suffering from fetal distress].
Zhongguo Dang Dai Er Ke Za Zhi
PUBLISHED: 11-22-2011
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To study the expression of erythropoietin (EPO) and its receptor (EPOR) in the brain of newborn rats suffering fetal distress.
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Microwave-controlled facile synthesis of well-defined PbS hexapods.
J Nanosci Nanotechnol
PUBLISHED: 11-22-2011
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Controlled synthesis of well-defined PbS nanostructures in terms of size and shape has been strongly motivated by their potential applications ranging from solar photovoltaics to near-infrared optics. Hereby, we report a facile microwave-assistant method for ultrafast fabrication of PbS nanostructures, by which uniform PbS hexapods with six arms stretching along six (100) directions of the crystal seeds have been easily synthesized within minutes. Various morphologies including rectangle plates, uniform cubes as well as nanoparticles were obtained by tuning the parameters for the formation of PbS nanocrystals. The results reveal that both concentration and feed ratio of precursors determine the growth of PbS nanocrystals significantly. And higher initial precursor concentration favors the formation of the hexapod structures. The process of crystal growth is monitored through scanning electron microscopy of PbS from different durations of the reaction. This controlled ultrafast synthesis of PbS structures at nanometer and micrometer scale with various morphologies may be promising in large scale fabrication of nanostructures. Based on the systematically study of the growth process, a possible mechanism for the formation of the hexapod-like structure is discussed.
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[Protection of hyperoxia-induced lung injury by granulocyte-macrophage colony-stimulating factor via RAGE-NF-?B signaling pathway in newborn rats].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 11-19-2011
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To explore the effects of granulocyte-macrophage colony-stimulating factor (GMCSF) on hyperoxia exposure lung injury in newborn rats and elucidate its protective mechanism of operating via the signaling pathway of advanced glycation end products (RAGE)-NF-?B.
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Mesorhizobium silamurunense sp. nov., isolated from root nodules of Astragalus species.
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 11-04-2011
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Four rhizobial strains representing a previously defined novel group in the genus Mesorhizobium and isolated from Astragalus species in China were further characterized using a polyphasic approach. Phylogenetic analysis of 16S rRNA gene sequences showed that these Gram-negative bacteria belonged to the genus Mesorhizobium, with Mesorhizobium plurifarium LMG 11892(T) as the closest neighbour sharing a sequence similarity of 99.8 %. Comparative sequence analysis of the atpD, recA, glnII, rpoB, nodC and nifH genes, SDS-PAGE of whole-cell soluble proteins, DNA-DNA hybridization, fatty acid profiles and a series of phenotypic and physiological tests differentiated the novel group from all recognized species of the genus Mesorhizobium. Based on the data obtained in the present and previous studies, this group represents a novel species within the genus Mesorhizobium, for which the name Mesorhizobium silamurunense sp. nov. is proposed. The type strain is CCBAU 01550(T) (= HAMBI 3029(T) = LMG 24822(T)), and could form effective nodules on Astragalus membranaceus, Astragalus adsurgens and Caragana intermedia, and ineffective nodules on Phaseolus vulgaris in cross-nodulation tests.
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Chiral 1D Dy(III) compound showing slow magnetic relaxation.
Dalton Trans
PUBLISHED: 10-27-2011
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Herein, we present one chiral Dy(III) compound, namely Dy(L)(3)(1, HL = 2-methylbenzoic acid), synthesized from the achiral HL ligand. Within 1, along a direction the seven-coordinated Dy(III) ion are bridged by double L carboxylate and single L oxygen to give rise to the 1D helical chain. The magnetic studies suggest small intra-chain ferromagnetic interactions. Alternating current (AC) magnetic measurements show a frequency dependence of magnetic susceptibilities in both in-phase, ?, and out-of-phase, ?. However, no obvious peak can be found even under 1000 Oe static field, suggesting the prevalence of quantum tunnelling effect at low temperature.
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Constituents with DNA topoisomerases I and II inhibitory activity and cytotoxicity from the roots of Rubia cordifolia.
Planta Med.
PUBLISHED: 10-06-2011
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Activity-directed isolation of the ethyl acetate fraction from the roots of Rubia cordifolia resulted in the identification of a new anthraquinone, 1,3,6-trihydroxy-2-hydroxymethyl-9,10-anthraquinone-3- O- ?- L-rhamnopyranosyl-(1???2)- ?-D-(6-O-acetyl)-glucopyranoside (1), two new dihydronaphtoquinones, 1,4-dihydroxy-2-carbomethoxy-3-prenylnaphthalene-1-O- ?-D-glucopyranoside (2) and mollugin-1-O- ?- D-glucopyranoside (3), and a new monoterpenoid, 3 R,3a S,4 R,6a R-3,4,6-tris(hydroxymethyl)-3,3a,4,6a-tetrahydro-2 H-cyclopenta[ B]furan-2-one (4), together with nine known compounds (5-13). The structures of these compounds were elucidated on the basis of spectroscopic evidence. In addition, their DNA topoisomerases I and II inhibitory activity and cytotoxicity were measured.
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Development of an immunoaffinity chromatography purification and ultra performance liquid chromatography tandem mass spectrometry method for determination of 12 sulfonamides in beef and milk.
J. Agric. Food Chem.
PUBLISHED: 08-25-2011
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A highly selective and sensitive method was developed for the simultaneous determination of 12 sulfonamides in beef and milk by immunoaffinity chromatography purification coupled to ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The MS/MS conditions, UPLC mobile phase, injection solution, sample purification process, and matrix effect were studied to optimize the operating conditions. The limits of detection (LODs) of the instrument for the studied sulfonamides ranged from 0.4 to 2.0 ?g L(-1), being 1.6-8.0 ?g kg(-1) for beef and 1.8-6.4 ?g kg(-1) for milk. The standard solution was diluted with blank beef or milk matrix for the construction of calibration curves, which had a linear range from 10 to 200 ?g kg(-1) and regression coefficients higher than 0.990 (n=10) for all the studied sulfonamides. Samples spiked at 10, 20, and 100 ?g kg(-1) showed recoveries above 70% and relative standard deviations below 10%.
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Multiple extra-synaptic spillover mechanisms regulate prolonged activity in cerebellar Golgi cell-granule cell loops.
J. Physiol. (Lond.)
PUBLISHED: 06-13-2011
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Despite a wealth of in vitro and modelling studies it remains unclear how neuronal populations in the cerebellum interact in vivo. We address the issue of how the cerebellar input layer processes sensory information, with particular focus on the granule cells (input relays) and their counterpart inhibitory interneurones, Golgi cells. Based on the textbook view, granule cells excite Golgi cells via glutamate forming a negative feedback loop. However, Golgi cells express inhibitory mGluR2 receptors suggesting an inhibitory role for glutamate. We set out to test this glutamatergic paradox in Golgi cells. Here we show that granule cells and Golgi cells interact through extra-synaptic signalling mechanisms during sensory information processing, as well as synaptic mechanisms. We demonstrate that such interactions depend on granule cell-derived glutamate acting via inhibitory mGluR2 receptors leading causally to the suppression of Golgi cell activity for several hundreds of milliseconds. We further show that granule cell-derived inhibition of Golgi cell activity is regulated by GABA-dependent extra-synaptic Golgi cell inhibition of granule cells, identifying a regulatory loop in which glutamate and GABA may be critical regulators of Golgi cell–granule cell functional activity. Thus, granule cells may promote their own prolonged activity via paradoxical feed-forward inhibition of Golgi cells, thereby enabling information processing over long timescales.
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Receptor-like protein-tyrosine phosphatase ? enhances cell surface expression of neural adhesion molecule NB-3.
J. Biol. Chem.
PUBLISHED: 05-27-2011
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Neural adhesion molecule NB-3 plays an important role in the apical dendrite development of layer V pyramidal neurons in the visual cortex, and receptor-like protein-tyrosine phosphatase ? (PTP?) mediates NB-3 signaling in this process. Here we investigated the role of PTP? in regulating cell surface expression of NB-3. We found that cortical neurons from PTP? knock-out mice exhibited a lower level of NB-3 at the cell surface. When expressed in COS1 cells, NB-3 was enriched in the Golgi apparatus with a low level of cell surface expression. However, co-expression of PTP? increased the cell surface distribution of NB-3. Further analysis showed that PTP? facilitated Golgi exit of NB-3 and stabilized NB-3 protein at the cell surface by preventing its release from the plasma membrane. The extracellular region of PTP? but not its catalytic activity is necessary for its effect on NB-3 expression. Thus, the PTP?-mediated increase of NB-3 level at the cell surface represents a novel function of PTP? in NB-3 signaling in neural development.
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Association study of HLA-B alleles with idiopathic male infertility in Han population of China.
J. Assist. Reprod. Genet.
PUBLISHED: 05-26-2011
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To investigate the distributions of HLA-B alleles and estimate their associations with idiopathic male infertility in Chinese Han population.
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Electrochemically-driven large amplitude pH cycling for acid-base driven DNA denaturation and renaturation.
Anal. Chem.
PUBLISHED: 05-19-2011
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In this paper, we present an electrochemically driven large amplitude pH alteration method based on a serial electrolytic cell involving a hydrogen permeable bifacial working electrode such as Pd thin foil. The method allows solution pH to be changed periodically up to ±4~5 units without additional alteration of concentration and/or composition of the system. Application to the acid-base driven cyclic denaturation and renaturation of 290 bp DNA fragments is successfully demonstrated with in situ real-time UV spectroscopic characterization. Electrophoretic analysis confirms that the denaturation and renaturation processes are reversible without degradation of the DNA. The serial electrolytic cell based electrochemical pH alteration method presented in this work would promote investigations of a wide variety of potential-dependent processes and techniques.
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[Experimental study on the relationship between the ratio of length to width of slender narrow pedicle and random flap survival area in pig].
Zhonghua Zheng Xing Wai Ke Za Zhi
PUBLISHED: 05-10-2011
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To explore the relationship between the ratio of length to width of slender narrow pedicle and random flap survival area, and to provide a theoretical basis for the clinical application of slender narrow pedicle flaps.
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A pyrene maleimide with a flexible linker for sampling of longer inter-thiol distances by excimer formation.
PLoS ONE
PUBLISHED: 05-09-2011
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Pyrene-containing compounds are commonly used in a number of fluorescence-based applications because they can form excited-state dimers (excimers) by stacking interaction between excited-state and ground-state monomers. Their usefulness arises from the facts that excimer formation requires close proximity between the pyrenes and that the excimer emission spectrum is very different from that of the monomers. One of many applications is to assess proximity between specific sites of macromolecules labeled with pyrenes. This has been done using pyrene maleimide, a reagent that reacts with reduced thiols of cysteines, but its use for structural studies of proteins has been rather limited. This is because the introduction of two cysteines at sufficiently close distance from each other to obtain excimer fluorescence upon labeling with pyrene maleimide requires detailed knowledge of the protein structure or extensive site-directed mutagenesis trials. We synthesized and tested a new compound with a 4-carbon methylene linker placed between the maleimide and the pyrene (pyrene-4-maleimide), with the aim of increasing the sampling distance for excimer formation and making the use of excimer fluorescence simpler and more widespread. We tested the new compound on thiol-modified oligonucleotides and showed that it can detect proximity between thiols beyond the reach of pyrene maleimide. Based on its spectroscopic and chemical properties, we suggest that pyrene-4-maleimide is an excellent probe to assess proximities between cysteines in proteins and thiols in other macromolecules, as well as to follow conformational changes.
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Genetic polymorphisms of 10 X-STR among four ethnic populations in northwest of China.
Mol. Biol. Rep.
PUBLISHED: 05-03-2011
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In the present study, 10 short tandem repeats (STR) (HPRTB, DXS6789, DXS6799, DXS6804, DXS7130, DXS7132, DXS7133, DXS7423, DXS7424, and DXS8378) on X chromosome were investigated among four ethnic populations (431 individuals) in northwest of China, in order to learn about the genetic diversity, forensic suitability, and possible genetic affinities of the populations. The polymorphism information content (PIC) values for the ten loci range from 0.340 to 0.810, and the observed heterozygosity values for the ten loci range from 0.397 to 0.860, the results indicated that the ten loci have a moderate degree of variability in the four populations, and each population has its own characteristics of genetic structure. A Neighbor-joining (NJ) tree constructed on the basis of the generated data shows very low genetic distance between Han, Mongolian and Tibetan, Dongxiang and Tu as well as between Salar and Bonan populations. Our results based on genetic distance analysis are consistent with the results of earlier studies based on linguistics and the immigration history and origin of these populations. These STR loci on the X chromosome studied here are not only useful in showing significant genetic variation between the populations, but also are suitable for human identity testing among the four populations.
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Erythropoietin ameliorates renal ischemia and reperfusion injury via inhibiting tubulointerstitial inflammation.
J. Surg. Res.
PUBLISHED: 04-05-2011
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Tubulointerstitial inflammation is the characteristics of renal ischemia reperfusion injury (IRI) that is inevitable in kidney transplantation. Erythropoietin (EPO) has recently been shown to have protective effects on renal IRI by anti-apoptosis and anti-oxidation. Here, the effect and mechanism of EPO on renal IRI were further investigated, with a focus on tubulointerstitial inflammation.
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Two new sesquiterpene polyol esters from the root barks of Celastrus angulatus.
J Asian Nat Prod Res
PUBLISHED: 04-05-2011
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Angulatin F (1) and angulatin I (2), two new sesquiterpene polyol esters, were isolated from the root barks of Celastrus angulatus, together with six known compounds 1?,2?-diacetoxy-4?,6?-dihydroxy-8?-isobutanoyloxy-9?-benzoyloxy-15-(?-methyl) butanoyloxy-?-dihydroagrofuran (3), angulatin A (4), angulatin B (5), celangulatin E (6), 1?,2?,15-triacetoxy-4?,6?-dihydroxy-8?-isobutanoyloxy-9?-benzoyloxy-?-dihydroagrofuran (7), and celangulin I (8). The structures of 1 and 2 were elucidated as 1?,2?,6?,15-tetraacetoxy-4?-hydroxy-8?,9?-difuroyloxy-?-dihydroagrofuran and 1?,2?,6?,8?,15-pentaacetoxy-4?-hydroxy-9?-furoyloxy-?-dihydroagrofuran by spectroscopic means.
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Visualization of nitroxyl in living cells by a chelated copper(II) coumarin complex.
Org. Lett.
PUBLISHED: 02-15-2011
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The coumarin-based probe Cu(II)-COT1 was successfully developed for the detection of HNO on the basis of the reduction reaction. In addition, highly selective "turn on" type fluorogenic behavior upon the addition of Angelis salt (Na(2)N(2)O(3)) was also applied to bioimaging in A375 cells.
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Microwave synthesis of zinc sulfite and porous zinc oxide microrods.
Chem. Commun. (Camb.)
PUBLISHED: 02-14-2011
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ZnSO(3) microrods with uniform size and shape can be prepared under microwave irradiation at much higher speed than a conventional heating bath, usually in minutes. The annealing of ZnSO(3) microrods produced porous ZnO microrods with pore size between 50-200 nm.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.