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Find video protocols related to scientific articles indexed in Pubmed.
Nationwide Trends in Mastectomy for Early-Stage Breast Cancer.
JAMA Surg
PUBLISHED: 11-20-2014
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Accredited breast centers in the United States are measured on performance of breast conservation surgery (BCS) in the majority of women with early-stage breast cancer. Prior research in regional and limited national cohorts suggests a recent shift toward increasing performance of mastectomy in patients eligible for BCS.
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Mutations in the ABCA3 gene are associated with cataract-microcornea syndrome.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 11-20-2014
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Cataract-microcornea syndrome (CCMC) is an autosomal dominant inherited disease characterized by the association of congenital cataract and microcornea without any other systemic anomaly or dysmorphism. Although mutations of several genes have been shown to cause dominant CCMC, in many patients the causative gene has not yet been identified. Our aim was to identify the disease-associated gene in Chinese patients with CCMC.
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Influence of Recombinant Lentiviral Vector Encoding miR-15a/16-1 in Biological Features of Human Nasopharyngeal Carcinoma CNE-2Z Cells.
Cancer Biother. Radiopharm.
PUBLISHED: 11-19-2014
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Abstract MicroRNAs can function as tumor suppressor miRNAs. Bcl-2 is an antiapoptotic gene overexpressed in many tumors, including nasopharyngeal carcinoma (NPC). It is reported that microRNA-15a (miR-15a) and microRNA-16-1 (miR-16-1) could act as bcl-2 inhibitors. To investigate their effects on NPC, the authors used recombinant lentiviral vector to upregulate the expression of miR-15a/16-1 in NPC CNE-2Z cells. The authors divided cells into the control group, transfection group, radiotherapy group, and transfection-radiotherapy group. In this experiment, reverse transcription-quantitative polymerase chain reaction was used to detect the expression of miR-15a/16-1 and bcl-2 mRNA. Cell proliferation was analyzed by MTT assay. Flow cytometry was used to measure cell apoptosis. Radiosensitivity was measured using colony-forming experiment. The protein expression of bcl-2 was measured by western blot, the activation levels of caspase were detected by a spectrophotometric method. After transfection, cell proliferation was inhibited, while the apoptosis rate and radiosensitivity were increased. In addition, the activation of caspase-2 and caspase-3 was aggrandized correspondingly. Although the expression levels of bcl-2 mRNA in each group had no difference, the protein expression of bcl-2 was downregulated. These results suggested that miR-15a/16-1 could inhibit cell proliferation and increase the apoptosis and radiosensitivity of CNE-2 cells, by regulating the bcl-2 gene at post-transcriptional level and by increasing the activation of caspase-2 and caspase-3.
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[Immunoprotective effect of a plasmid DNA vaccine pCMV-LC3-Ag85B against Mycobaterium tuberculosis].
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi
PUBLISHED: 11-07-2014
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Objective To construct an autophagy-targeted vaccine harboring the genes encoding Ag85B and microtubule-associated protein light chain-3 (LC3) and to explore its immunoprotection against Mycobacterium tuberculosis (MTB). Methods The pCMV-LC3-Ag85B plasmid was constructed and used to transfect RAW264.7 cells. The level of LC3-Ag85B was detected using Western blotting. Then, BALB/c mice were immunized with pCMV, pCMV-Ag85B and pCMV-LC3-Ag85B plasmid, respectively. In vitro, two weeks after the last immunization, the secretion of IL-2, IFN-?, IL-4 and IL-10 from Ag85B-stimulated lymphocytes was measured by ELISA. Three months after the last immunization, all mice were challenged with MTB H37Rv via the tail vein and the bacterial loads in their spleens and lungs were determined by colony formation assay. Results The LC3-Ag85B fusion protein was expressed in RAW264.7 cells that had been transfected with pCMV-LC3-Ag85B and the expression level was in a dose-dependent manner. Compared with the pCMV-Ag85B treatment group, pCMV-LC3-Ag85B-immunized mice showed a significant increase of IL-2 and IFN-? levels and the lower loads of MTB in the spleens and lungs. Conclusion pCMV-LC3-Ag85B can enhance a specific Th1-predominant immunity and a superior immunoprotection against MTB, which may provide a new practical strategy for the development of improved vaccines against MTB.
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HBsAg-negative hepatitis B virus infection and hepatocellular carcinoma.
Discov Med
PUBLISHED: 10-23-2014
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Hepatitis B virus (HBV) is the major causative agent of chronic hepatitis, hepatic decompensation, liver cirrhosis, and hepatocellular carcinoma (HCC). HBV-related serum markers are widely used in clinical diagnosis and prognosis for HBV infection. Among them, the HBV surface antigen (HBsAg) was once regarded as the sole marker for infection. The serum levels of HBsAg, along with HBV DNA levels, are the most important predictors of the risk of developing HCC. Higher levels of HBsAg are usually connected with a higher risk and lower levels of HBsAg are usually connected with a lower risk. However, negative results for serum HBsAg tests do not always represent a clearance or inactivating status of HBV viruses. HCC could still develop in the absence of detectable HBsAg in serum. This situation is called occult hepatitis B virus infection (OBI). OBI is characterized by the presence of HBV viral genome in the patient's liver but no virus surface antigen (HBsAg) detected in serum by commonly used immunoassays. Although there may not be much difference in the extent of HBV genome replication in OBI (HBsAg negative) and the overt HBV infections (HBsAg positive), the duration of HBV replication and its pathological consequences last much longer in OBI than in overt infections. This paper provides a comprehensive review on the reasons behind OBI, the clinical impact of OBI on the development of HCC, and the urgency for implementing new methodological techniques for detecting OBI.
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[Changes and clinical significance of peripheral blood natural killer cells in neonates with bacterial pneumonia].
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi
PUBLISHED: 10-02-2014
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Objective To detect the percentage of total natural killer (NK) cells and its different populations in the peripheral blood from neonates with bacterial pneumonia and discuss the clinical significance of NK cells in the pathogenesis of bacterial pneumonia. Methods Flow cytometry was performed to detect the percentages of NK cells and its subsets in peripheral blood lymphocytes from 38 cases of neonatal bacterial pneumonias and 18 cases of normal neonates. Patients recruited were divided into two groups according to hospitalization days and numbers of peripheral leukocytes: hospitalization days within 10 days (including 10 days) as group A, and more than 10 days as group B; the number of peripheral blood leukocytes <5.0×10(9)/L or >20.0×10(9)/L as severe infection group, and 5.0×10(9)/L< number of peripheral blood leukocytes <20.0×10(9)/L as mild infection group. Results The percentages of peripheral blood NK cells and CD3(-)CD56(neg)CD16(bright) subset in the neonates with bacterial pneumonia were significantly lower than those of the normal newborns (P<0.01), but there were no statistically significant differences in CD3(-)CD56(bright)CD16(neg/dim) and CD3(-)CD56(dim)CD16(bright) subsets. The percentage of CD3(-)CD56(neg)CD16(bright) subset in group A was significantly lower than that of the normal newborns (P<0.01), while the percentages of the total NK cells and other subsets had no statistical significance. The neonates with bacterial pneumonia had significantly lower percentages of the total NK cells and CD3(-)CD56(neg)CD16(bright) subset in group B as compared with the normal neonates (P<0.01). And the percentages of the total NK cells and its subsets in group B were also lower than those in group A (P<0.05). The percentages of NK cells and each subset in severe infection group were significantly lower than those in mild infection group (P<0.05). Conclusion To the neonates who suffer from bacterial pneumonia, the more serious and the longer hospital stay, the lower the percentages of NK cells and its subsets are.
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Effects of low-fat diet on serum lipids in premenopausal and postmenopausal women: a meta-analysis of randomized controlled trials.
Menopause
PUBLISHED: 09-25-2014
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This study aims to conduct a meta-analysis to evaluate the effects of a low-fat diet, in comparison with participants' usual diet, on serum lipids in premenopausal and postmenopausal women.
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The role of specific PP2A complexes in the dephosphorylation of ?-H2AX.
J. Cell. Sci.
PUBLISHED: 09-20-2014
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The formation of ?-H2AX in response to DNA double-strand breaks (DSBs) marks damaged regions for recognition and repair. Dephosphorylation of ?-H2AX is required for cells to resume cell cycle. However, the mechanisms of ?-H2AX dephosphorylation remain underexplored. Using a loss of function screen, we identified PP2A specific subunits, B56? and ?4, involved in elimination of ?-H2AX during DSBs repair process. In the early stage of DSBs repair the inhibitory subunit ?4 binds and renders PP2Ac inactive. As DNA is repaired, ?4 releases PP2Ac and triggers the assembly of an active PP2A B56? holoenzyme. PP2A B56?, which translocates from cytoplasm into the nucleus upon DNA damage, is responsible for a direct dephosphorylation of ?-H2AX. Suppression of both B56? and ?4 leads to persistence of ?-H2AX and defects in DNA repair. In contrast, the rapid clearance of ?-H2AX in human hepatocarcinoma is correlated with the over-expression of both B56? and ?4. Functional analysis reveals that PP2A B56? coordinates with ?4 in accelerating HR repair upon DNA damage. Together, these observations gain insight of how ?-H2AX dephosphorylation is kinetically regulated during DNA repair response.
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SPAG6 silencing inhibits the growth of the malignant myeloid cell lines SKM-1 and K562 via activating p53 and caspase activation-dependent apoptosis.
Int. J. Oncol.
PUBLISHED: 09-13-2014
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SPAG6, which is a novel cancer-testis antigen, is overexpressed in myeloid malignancies. Previously, SPAG6 was found in UPD (uniparental disomy) region of myeloid cell DNA from MDS patients and reported that SPAG6 may be a predictive marker of minimal residual disease in pediatric acute myeloid, but the biological role of SPAG6 in myeloid malignancies remains unclear. The present study was undertaken to determine the expression and functional significance of SPAG6 in malignant myeloid hematologic cell lines. A short hairpin RNA (shRNA) targeting SPAG6 was designed that could specifically inhibit SPAG6 expression at the mRNA and protein levels when introduced into the malignant myeloid hematologic cell lines SKM-1 and K562. The results from flow cytometry and CCK-8 assays showed that SPAG6 silencing inhibited the proliferation of SKM-1/K562 by inducing apoptosis. Furthermore, SPAG6 silencing resulted in activation of caspase-3, -9 and -8 and upregulated the mRNA and protein expression of p53 and PTEN. Then, we subcutaneously inoculated the monoclonal cells into NOD/SCID mice to establish xenograft models, and we found that the SPAG6-shRNA lentivirus dramatically inhibited tumor growth and increased apoptosis in vivo. These findings demonstrate that SPAG6 might have a role in malignant myeloid hematologic cell proliferation and apoptosis by regulating caspase proteins and p53, suggesting that SPAG6 may be a potential therapeutic target.
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A global view of transcriptome dynamics during Sporisorium scitamineum challenge in sugarcane by RNA-Seq.
PLoS ONE
PUBLISHED: 08-29-2014
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Sugarcane smut caused by Sporisorium scitamineum is a critical fungal disease in the sugarcane industry. However, molecular mechanistic studies of pathological response of sugarcane to S. scitamineum are scarce and preliminary. Here, transcriptome analysis of sugarcane disease induced by S. scitamineum at 24, 48 and 120 h was conducted, using an S. scitamineum-resistant and -susceptible genotype (Yacheng05-179 and "ROC"22). The reliability of Illumina data was confirmed by real-time quantitative PCR. In total, transcriptome sequencing of eight samples revealed gene annotations of 65,852 unigenes. Correlation analysis of differentially expressed genes indicated that after S. scitamineum infection, most differentially expressed genes and related metabolic pathways in both sugarcane genotypes were common, covering most biological activities. However, expression of resistance-associated genes in Yacheng05-179 (24-48 h) occurred earlier than those in "ROC"22 (48-120 h), and more transcript expressions were observed in the former, suggesting resistance specificity and early timing of these genes in non-affinity sugarcane and S. scitamineum interactions. Obtained unigenes were related to cellular components, molecular functions and biological processes. From these data, functional annotations associated with resistance were obtained, including signal transduction mechanisms, energy production and conversion, inorganic ion transport and metabolism, and defense mechanisms. Pathway enrichment analysis revealed that differentially expressed genes are involved in plant hormone signal transduction, flavonoid biosynthesis, plant-pathogen interaction, cell wall fortification pathway and other resistance-associated metabolic pathways. Disease inoculation experiments and the validation of in vitro antibacterial activity of the chitinase gene ScChi show that this sugarcane chitinase gene identified through RNA-Seq analysis is relevant to plant-pathogen interactions. In conclusion, expression data here represent the most comprehensive dataset available for sugarcane smut induced by S. scitamineum and will serve as a resource for finally unraveling the molecular mechanisms of sugarcane responses to S. scitamineum.
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Exome sequencing reveals mutation in GJA1 as a cause of keratoderma-hypotrichosis-leukonychia totalis syndrome.
Hum. Mol. Genet.
PUBLISHED: 08-28-2014
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Keratoderma-hypotrichosis-leukonychia totalis syndrome (KHLS) is an extremely rare, autosomal-dominant disorder characterized by severe skin hyperkeratosis, congenital alopecia and leukonychia totalis. The genetic defect underlying KHLS remained undetermined. By performing whole-exome sequencing in a family with KHLS, we identified a heterozygous mutation (c.23G>T [p.Gly8Val]) in GJA1, which cosegregated with the phenotype in the family. In an additional affected individual, we also found the identical de novo mutation which was absent in his unaffected family members. GJA1 encodes a gap junction protein connexin 43 (Cx43) which is ubiquitously expressed in various organs, including the epidermis and hair follicles. In vitro studies on HEK293 cells expressing Cx43(Gly8Val) found that the protein formed gap junction plaques between adjacent transfected cells, as observed in the wild-type. Dye-transfer experiments by microinjection of Lucifer yellow displayed functional gap junction of the Cx43(Gly8Val) mutant. Using patch clamp and Ca(2+) imaging methods, we observed that the Cx43(Gly8Val) hemichannel had significantly more openings than Cx43(WT), facilitating Ca(2+) influx at resting potential. Such gain-of-function effect might result in cytoplasmic Ca(2+) overload, accelerated apoptosis of keratinocytes and subsequent skin hyperkeratosis. Taken together, our results demonstrated that, with probably enhanced hemichannel activities, a mutation in GJA1 is linked to KHLS without extracutaneous involvement.
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Small-molecule survivin inhibitor YM155 enhances radiosensitization in esophageal squamous cell carcinoma by the abrogation of G2 checkpoint and suppression of homologous recombination repair.
J Hematol Oncol
PUBLISHED: 08-20-2014
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Survivin is overexpressed in cancer cells and plays a crucial role in apoptosis evasion. YM155, a small-molecule inhibitor of survivin, could enhance the cytotoxicity of various DNA-damaging agents. Here, we evaluated the radiosensitizaion potential of YM155 in human esophageal squamous cell carcinoma (ESCC).
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Genome-wide association analysis of Vogt-Koyanagi-Harada syndrome identifies two new susceptibility loci at 1p31.2 and 10q21.3.
Nat. Genet.
PUBLISHED: 08-10-2014
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To identify new genetic risk factors for Vogt-Koyanagi-Harada (VKH) syndrome, we conducted a genome-wide association study of 2,208,258 SNPs in 774 cases and 2,009 controls with follow-up in a collection of 415 cases and 2,006 controls and a further collection of 349 cases and 1,588 controls from a Han Chinese population. We identified three loci associated with VKH syndrome susceptibility (IL23R-C1orf141, rs117633859, P(combined) = 3.42 × 10(-21), odds ratio (OR) = 1.82; ADO-ZNF365-EGR2, rs442309, P(combined) = 2.97 × 10(-11), OR = 1.37; and HLA-DRB1/DQA1, rs3021304, P(combined) = 1.26 × 10(-118), OR = 2.97). The five non-HLA genes were all expressed in human iris tissue. IL23R was also expressed in the ciliary body, and EGR2 was expressed in the ciliary body and choroid. The risk G allele of rs117633859 in the promoter region of IL23R exhibited low transcriptional activation in a cell-based reporter assay and was associated with diminished IL23R mRNA expression in human peripheral blood mononuclear cells.
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Eukaryotic elongation factor 2 kinase confers tolerance to stress conditions in cancer cells.
Cell Stress Chaperones
PUBLISHED: 07-19-2014
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Eukaryotic elongation factor 2 (eEF2) is a member of the GTP-binding translation elongation factor family that is essential for protein synthesis. eEF2 kinase (eEF2K) is a structurally and functionally unique protein kinase in the calmodulin-mediated signaling pathway. eEF2K phosphorylates eEF2, thereby inhibiting eEF2 function under stressful conditions. eEF2K regulates numerous processes, such as protein synthesis, cell cycle progression, and induction of autophagy and apoptosis in cancer cells. This review will demonstrate the mechanisms underlying eEF2K activity in cancer cells under different stresses, such as nutrient deprivation, hypoxia, and DNA damage via eEF2 regulation. In vivo, in vitro, and clinical studies indicated that eEF2K may be a novel biomarker and therapeutic target for cancer.
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Epithelial ovarian cancer: A case report.
Exp Ther Med
PUBLISHED: 07-10-2014
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An 82-year-old female was diagnosed with ovarian cancer in May 2004. Following gynecological surgery, pathological evaluation showed stage IIIC epithelial ovarian cancer. From June 2004 to January 2005, the patient received six cycles of conventional treatment combined with intravenous paclitaxel (Taxol(®)) and cisplatin. The patient developed abdominal distension and experienced a gradual deterioration in health during 2007, with admission to The First Affiliated Hospital in May 2007. The patient presented with severe abdominal distension and breathing difficulty on May 15 and appeared to be in critical condition. Ultrasound examination revealed massive ascites and left-side pleural effusion. Thoracentesis and abdominocentesis were performed, and 300 mg carboplatin was administered intraperitoneally on May 19, followed by a second abdominocentesis on May 21. However, these treatments did not alleviate the symptoms, and 200 mg bevacizumab was administered by intravenous infusion on May 27. The condition of the patient gradually improved and 400 mg bevacizumab was administered by intravenous infusion every two weeks from June 9. From December, the dosage of bevacizumab was reduced to 200 mg every two weeks. In addition, 300 mg carboplatin was administered intraperitoneally on November 4 and intraperitoneal carboplatin chemotherapy was repeated thereafter. The patient exhibited disease-free survival until July 2009, at which time disease progression was observed and the cancer recurred in August 2009. The patient died of multiple organ failure in September 2009. Bevacizumab rapidly eliminated the patient's massive ascites and pleural effusion, and achieved an effect that was not possible with other treatments. Therefore, bevacizumab is an effective therapy for late-stage relapse and refractory ovarian cancer.
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A novel COL4A5 mutation identified in a Chinese Han family using exome sequencing.
Biomed Res Int
PUBLISHED: 07-06-2014
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Alport syndrome (AS) is a monogenic disease of the basement membrane (BM), resulting in progressive renal failure due to glomerulonephropathy, variable sensorineural hearing loss, and ocular anomalies. It is caused by mutations in the collagen type IV alpha-3 gene (COL4A3), the collagen type IV alpha-4 gene (COL4A4), and the collagen type IV alpha-5 gene (COL4A5), which encodes type IV collagen ?3, ?4, and ?5 chains, respectively. To explore the disease-related gene in a four-generation Chinese Han pedigree of AS, exome sequencing was conducted on the proband, and a novel deletion mutation c.499delC (p.Pro167Glnfs*36) in the COL4A5 gene was identified. This mutation, absent in 1,000 genomes project, HapMap, dbSNP132, YH1 databases, and 100 normal controls, cosegregated with patients in the family. Neither sensorineural hearing loss nor typical COL4A5-related ocular abnormalities (dot-and-fleck retinopathy, anterior lenticonus, and the rare posterior polymorphous corneal dystrophy) were present in patients of this family. The phenotypes of patients in this AS family were characterized by early onset-age and rapidly developing into end-stage renal disease (ESRD). Our discovery broadens the mutation spectrum in the COL4A5 gene associated with AS, which may also shed new light on genetic counseling for AS.
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The choice of reference genes for assessing gene expression in sugarcane under salinity and drought stresses.
Sci Rep
PUBLISHED: 07-04-2014
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Sugarcane (Saccharum spp. hybrids) is a world-wide cash crop for sugar and biofuel in tropical and subtropical regions and suffers serious losses in cane yield and sugar content under salinity and drought stresses. Although real-time quantitative PCR has a numerous advantage in the expression quantification of stress-related genes for the elaboration of the corresponding molecular mechanism in sugarcane, the variation happened across the process of gene expression quantification should be normalized and monitored by introducing one or several reference genes. To validate suitable reference genes or gene sets for sugarcane gene expression normalization, 13 candidate reference genes have been tested across 12 NaCl- and PEG-treated sugarcane samples for four sugarcane genotypes using four commonly used systematic statistical algorithms termed geNorm, BestKeeper, NormFinder and the deltaCt method. The results demonstrated that glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and eukaryotic elongation factor 1-alpha (eEF-1a) were identified as suitable reference genes for gene expression normalization under salinity/drought-treatment in sugarcane. Moreover, the expression analyses of SuSK and 6PGDH further validated that a combination of clathrin adaptor complex (CAC) and cullin (CUL) as reference should be better for gene expression normalization. These results can facilitate the future research on gene expression in sugarcane under salinity and drought stresses.
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A Highly Selective Two-Photon Fluorescent Probe for Detection of Cadmium(II) Based on Intramolecular Electron Transfer and its Imaging in Living Cells.
Chemistry
PUBLISHED: 07-02-2014
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A new quinoline-based probe was designed that shows one-photon ratiometric and two-photon off-on changes upon detecting Cd(2+) . It exhibits fluorescence emission at 407?nm originating from quinoline groups in Tris-HCl (25?mM, pH?7.40), H2 O/EtOH (8:2, v/v). Coordination with Cd(2+) causes quenching of the emission at 407?nm and simultaneously yields a remarkable redshift of the emission maximum to 500?nm with an isoemissive point at 439?nm owing to an intramolecular charge-transfer mechanism. Thus, dual-emission ratiometric measurement with a large redshift (??=93?nm) and significant changes in the ratio (F500 /F439 ) of the emission intensity (R/R0 up to 27) is established. Moreover, the sensor H2 L displays excellent selectivity response, high sensitive fluorescence enhancement, and strong binding ability to Cd(2+) . Coordination properties of H2 L towards Cd(2+) were fully investigated by absorption/fluorescence spectroscopy, which indicated the formation of a 2:1 H2 L/Cd(2+) complex. All complexes were characterized by X-ray crystallography, and TD-DFT calculations were performed to understand the origin of optical selectivity shown by H2 L. Two-photon fluorescence microscopy experiments have demonstrated that H2 L could be used in live cells for the detection of Cd(2+) .
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Biomimetic chemical sensors using bioengineered olfactory and taste cells.
Bioengineered
PUBLISHED: 07-02-2014
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Biological olfactory and taste systems are natural chemical sensing systems with unique performances for the detection of environmental chemical signals. With the advances in olfactory and taste transduction mechanisms, biomimetic chemical sensors have achieved significant progress due to their promising prospects and potential applications. Biomimetic chemical sensors exploit the unique capability of biological functional components for chemical sensing, which are often sourced from sensing units of biological olfactory or taste systems at the tissue level, cellular level, or molecular level. Specifically, at the cellular level, there are mainly two categories of cells have been employed for the development of biomimetic chemical sensors, which are natural cells and bioengineered cells, respectively. Natural cells are directly isolated from biological olfactory and taste systems, which are convenient to achieve. However, natural cells often suffer from the undefined sensing properties and limited amount of identical cells. On the other hand, bioengineered cells have shown decisive advantages to be applied in the development of biomimetic chemical sensors due to the powerful biotechnology for the reconstruction of the cell sensing properties. Here, we briefly summarized the most recent advances of biomimetic chemical sensors using bioengineered olfactory and taste cells. The development challenges and future trends are discussed as well.
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The role of small RNAs on phenotypes in reciprocal hybrids between Solanum lycopersicum and S. pimpinellifolium.
BMC Plant Biol.
PUBLISHED: 06-29-2014
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BackgroundReciprocal hybrids showing different phenotypes have been well documented in previous studies, and many factors accounting for different phenotypes have been extensively investigated. However, less is known about whether the profiles of small RNAs differ between reciprocal hybrids and how these small RNAs affect gene expression and phenotypes. To better understand this mechanism, the role of small RNAs on phenotypes in reciprocal hybrids was analysed.ResultsReciprocal hybrids between Solanum lycopersicum cv. Micro-Tom and S. pimpinellifolium line WVa700 were generated. Significantly different phenotypes between the reciprocal hybrids were observed, including fruit shape index, single fruit weight and plant height. Then, through the high-throughput sequencing of small RNAs, we found that the expression levels of 76 known miRNAs were highly variable between the reciprocal hybrids. Subsequently, a total of 410 target genes were predicted to correspond with these differentially expressed miRNAs. Furthermore, gene ontology (GO) annotation indicated that those target genes are primarily involved in metabolic processes. Finally, differentially expressed miRNAs, such as miR156f and 171a, and their target genes were analysed by qRT-PCR, and their expression levels were well correlated with the different phenotypes.ConclusionsThis study showed that the profiles of small RNAs differed between the reciprocal hybrids, and differentially expressed genes were also observed based on the different phenotypes. The qRT-PCR results of target genes showed that differentially expressed miRNAs negatively regulated their target genes. Moreover, the expression of target genes was well correlated with the observations of different phenotypes. These findings may aid in elucidating small RNAs contribute significantly to different phenotypes through epigenetic modification during reciprocal crossing.
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Characterization of a novel exported esterase Rv3036c from Mycobacterium tuberculosis.
Protein Expr. Purif.
PUBLISHED: 06-26-2014
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Mycobacterium tuberculosis possesses an unusually high number of genes involved in the metabolism of lipids. Driven by a newly described esterase motif SXXK in the amino acid sequence and a predicted signal peptide, the gene rv3036c from M. tuberculosis was cloned and characterized biochemically. Rv3036c efficiently hydrolyzes soluble p-nitrophenyl esters but not emulsified lipid. The highest activity of this enzyme was observed when p-nitrophenyl acetate (C2) was used as the substrate. Based on the activities, Rv3036c was classified as a nonlipolytic hydrolase. The results of immunoreactivity studies on the subcellular mycobacterial fractions suggested that the enzyme was present in the cell wall and cell membrane in mycobacteria. In summary, Rv3036c was characterized as a novel cell wall-anchored esterase from M. tuberculosis.
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Two new amides from a halotolerant fungus, Myrothecium sp. GS-17.
J. Antibiot.
PUBLISHED: 06-22-2014
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Two new amides, named N-acetyl-2,4,10,17-tetrahydroxyheptadecylamine (1) and N-acetyl-3,5,11,18-tetrahydroxyoctadecyl-2-amine (2), were isolated from a halotolerant fungus, Myrothecium sp. GS-17. Their structures were identified on the basis of spectroscopic characteristics. The cancer cell cytotoxicities of two compounds were evaluated, and compound 2 exhibited weak cytotoxicity in HL-60 cell line.The Journal of Antibiotics advance online publication, 1 October 2014; doi:10.1038/ja.2014.136.
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A cytosolic glucose-6-phosphate dehydrogenase gene, ScG6PDH, plays a positive role in response to various abiotic stresses in sugarcane.
Sci Rep
PUBLISHED: 06-10-2014
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As one of the key enzymes in the oxidative pentose phosphate pathway, glucose-6-phosphate dehydrogenase (G6PDH) plays a role in response to abiotic stresses and pathogenesis. Here, a full-length cDNA was obtained, designed as ScG6PDH from sugarcane. The ScG6PDH gene is 1,646?bp long with a 1,524-bp long ORF encoding 507 amino acid residues. Analysis of a phylogenetic tree indicated that this gene is a member of the cytosolic G6PDH gene family, which is consistent with results from a subcellular localization experiment. Based on a real-time quantitative RT-PCR performed under salt, drought, heavy metal (CdCl2) and low temperature (4°C) treatments, the transcription levels of the ScG6PDH gene were higher compared with transcription levels where these treatments were not imposed, suggesting a positive response of this gene to these environmental stresses. Furthermore, G6PDH activity was stimulated under 4°C, CdCl2, NaCl and PEG treatments, but the increments varied with treatment and sampling time, implying positive response to abiotic stresses, similar to the transcript of the G6PDH gene. Ion conductivity measurements and a histochemical assay provided indirect evidence of the involvement of the ScG6PDH gene in defense reactions to the above-mentioned abiotic stresses.
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Mutation analysis of Leber congenital amaurosis?associated genes in patients with retinitis pigmentosa.
Mol Med Rep
PUBLISHED: 05-28-2014
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The genetic defects underlying approximately half of all retinitis pigmentosa (RP) cases are unknown. A number of genes responsible for Leber congenital amaurosis (LCA) may also cause RP when they are mutated. Our previous study revealed that variants in the most frequently mutated nine exons accounted for approximately half of the mutations detected in a cohort of patients with LCA. The aim of the present study was to detect mutations in LCA-associated genes in patients with RP using two different strategies. Sanger sequencing was used to screen mutations in the nine exons in 293 patients with RP and exome sequencing was used to detect variants in 12 LCA-associated genes in 157 of the 293 patients with RP and then to validate the variants by Sanger sequencing. Potential pathogenic mutations were identified in four patients with early onset RP, including homozygous CRB1 mutations in two patients, compound heterozygous CRB1 mutations in one patient and compound heterozygous CEP290 mutations in one patient. The present study indicated that mutations in CEP290 may also be associated with RP but not with LCA. With the exception of CEP290, the remaining 11 genes known to be associated with LCA but not with RP are unlikely to be a common cause of RP.
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Red blood cell alloimmunization is influenced by recipient inflammatory state at time of transfusion in patients with sickle cell disease.
Br. J. Haematol.
PUBLISHED: 05-27-2014
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Sickle cell disease (SCD) patients are at increased risk of red blood cell (RBC) alloimmunization. Recipient inflammatory state at time of transfusion has been shown to regulate alloimmunization in murine models, but evidence is lacking in SCD patients. We retrospectively studied a cohort of alloimmunized SCD patients to determine the influence of pro-inflammatory SCD-related complications at time of transfusion on alloimmunization. For each transfusion, the presence of pro-inflammatory state, degree of RBC antigen matching, unit age, storage solution and alloantibody detection date were ascertained. Transfusion-associated pro-inflammatory events were compared between transfusions resulting and not resulting in new alloantibodies. Univariate analysis and multivariate logistic regression were performed. Fifty-two patients received 3166 pre-storage leuco-reduced transfusions of which 128 resulted in alloantibodies. Transfusions during inflammatory events were associated with increased alloantibody risk on univariate and multivariate analysis; acute chest syndrome and vaso-occlusive crisis showed strongest associations with alloimmunization. Increased antigen matching demonstrated a protective effect on alloimmunization (univariate and multivariate analysis). Although an association was seen between citrate-phosphate-dextrose (adenine) stored units and alloimmunization on univariate analysis, no effect was found on multivariate analysis. Identifying recipient pro-inflammatory states at time of transfusion that promote alloimmunization can impact RBC unit selection decisions for SCD patients at risk for alloimmunization.
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Melittin enhances radiosensitivity of hypoxic head and neck squamous cell carcinoma by suppressing HIF-1?.
Tumour Biol.
PUBLISHED: 05-22-2014
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Hypoxia is a widespread phenomenon present in many human solid tumors and is associated with a poor prognosis and therapy resistance. Here, we tested the feasibility of melittin, a major component of bee venom, on radiosensitization of hypoxic head and neck squamous cell carcinoma (HNSCC). CNE-2 and KB cells were treated with melittin and radiation response was determined. Cell viability, cytotoxicity and apoptosis induction were examined by CCK-8 assay, colony formation assay, and flow cytometry. Expression of hypoxia-inducible factor 1-alpha (HIF-1?) and vascular endothelial growth factor (VEGF) proteins were assessed using western blotting. Additionally, we also examined the effect of melittin on tumor growth and radiosensitivity in vivo using a xenograft model of HNSCC. Treatment with melittin resulted in cell growth inhibition, induction of cell apoptosis, and reduction of HIF-1? and VEGF expression, which has been linked to hypoxia cell radioresistance. In addition, intraperitoneal injection of melittin significantly reduced the growth of HNSCC tumors in CNE-2 tumor-bearing mice. These data suggest that melittin enhances radiosensitivity of HNSCC under hypoxia condition, and this is associated with the suppression of HIF-1? expression. Melittin appears to be a potential radiotherapy sensitization agent due to its significant antihypoxia activity.
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The high-affinity D2/D3 agonist D512 protects PC12 cells from 6-OHDA-induced apoptotic cell death and rescues dopaminergic neurons in the MPTP mouse model of Parkinson's disease.
J. Neurochem.
PUBLISHED: 05-19-2014
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In this study, in vitro and in vivo experiments were carried out with the high-affinity multifunctional D2/D3 agonist D-512 to explore its potential neuroprotective effects in models of Parkinson's disease and the potential mechanism(s) underlying such properties. Pre-treatment with D-512 in vitro was found to rescue rat adrenal Pheochromocytoma PC12 cells from toxicity induced by 6-hydroxydopamine administration in a dose-dependent manner. Neuroprotection was found to coincide with reductions in intracellular reactive oxygen species, lipid peroxidation, and DNA damage. In vivo, pre-treatment with 0.5 mg/kg D-512 was protective against neurodegenerative phenotypes associated with systemic administration of MPTP, including losses in striatal dopamine, reductions in numbers of DAergic neurons in the substantia nigra (SN), and locomotor dysfunction. These observations strongly suggest that the multifunctional drug D-512 may constitute a novel viable therapy for Parkinson's disease.
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[Pregabalin combined with intrathecal sufentanil infusion for breakthrough pain in patients with bone metastases].
Zhong Nan Da Xue Xue Bao Yi Xue Ban
PUBLISHED: 05-14-2014
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To evaluate the analgesic effect of pregabalin combined with intrathecal sufentanil infusion for the treatment of breakthrough pain in patients with bone metastases.
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Genome sequencing of Sporisorium scitamineum provides insights into the pathogenic mechanisms of sugarcane smut.
BMC Genomics
PUBLISHED: 05-10-2014
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Sugarcane smut can cause losses in cane yield and sugar content that range from 30 % to total crop failure. Losses tend to increase with the passage of years. Sporisorium scitamineum is the fungus that causes sugarcane smut. This fungus has the potential to infect all sugarcane species unless a species is resistant to biotrophic fungal pathogens. However, it remains unclear how the fungus breaks through the cell walls of sugarcane and causes the formation of black or gray whip-like structures on the sugarcane plants.
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The role of small RNAs in wide hybridisation and allopolyploidisation between Brassica rapa and Brassica nigra.
BMC Plant Biol.
PUBLISHED: 05-05-2014
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BackgroundAn allopolyploid formation consists of the two processes of hybridisation and chromosome doubling. Hybridisation makes a different genome combined in the same cell, and genome ¿shock¿ and instability occur during this process, whereas chromosome doubling results in doubling and reconstructing the genome dosage. Recent studies have demonstrated that small RNAs, play an important role in maintaining the genome reconstruction and stability. However, to date, little is known regarding the role of small RNAs during the process of wide hybridisation and chromosome doubling, which is essential to elucidate the mechanism of polyploidisation. Therefore, the genetic and DNA methylation alterations and changes in the siRNA and miRNA were assessed during the formation of an allodiploid and its allotetraploid between Brassica rapa and Brassica nigra in the present study.ResultsThe phenotypic analysis exhibited that the allotetraploid had high heterosis compared with their parents and the allodiploid. The methylation-sensitive amplification polymorphism (MSAP) analysis indicated that the proportion of changes in the methylation pattern of the allodiploid was significantly higher than that found in the allotetraploid, while the DNA methylation ratio was higher in the parents than the allodiploid and allotetraploid. The small RNAs results showed that the expression levels of miRNAs increased in the allodiploid and allotetraploid compared with the parents, and the expression levels of siRNAs increased and decreased compared with the parents B. rapa and B. nigra, respectively. Moreover, the percentages of miRNAs increased with an increase in the polyploidy levels, but the percentages of siRNAs and DNA methylation alterations decreased with an increase in the polyploidy levels. Furthermore, qRT-PCR analysis showed that the expression levels of the target genes were negatively corrected with the expressed miRNAs.ConclusionsThe study showed that siRNAs and DNA methylation play an important role in maintaining the genome stability in the formation of an allotetraploid. The miRNAs regulate gene expression and induce the phenotype variation, which may play an important role in the occurrence of heterosis in the allotetraploid. The findings of this study may provide new information for elucidating that the allotetraploids have a growth advantage over the parents and the allodiploids.
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Effects of lifestyle intervention improve cardiovascular disease risk factors in community-based menopausal transition and early postmenopausal women in China.
Menopause
PUBLISHED: 05-01-2014
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The aim of this study was to test the efficacy of a 12-month lifestyle intervention in improving cardiovascular disease risk factors in community-based menopausal transition and early postmenopausal women in China.
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STAT3 inhibitor NSC74859 radiosensitizes esophageal cancer via the downregulation of HIF-1?.
Tumour Biol.
PUBLISHED: 04-27-2014
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Radiotherapy is the main therapy for inoperable and locally advanced esophageal squamous cell carcinoma (ESCC). However, radioresistance in ESCC remains a challenge. The aim of this study is to investigate the radiosensitizing effects of STAT3 inhibitor NSC74859 on ESCC and explore the underlying mechanisms. ECA109 and TE13 cells were exposed to hypoxia, and treated with NSC74859 or radiation, alone or in combination. Cell proliferation, survival, apoptosis, and double-stranded DNA breaks (DSBs) were examined. Nude mice model of ECA109 xenograft was treated with radiation and/or NSC74859. The levels of STAT3, p-STAT3, HIF-1?, and VEGF were detected by Western blot analysis. NSC74859 efficiently radiosensitized ESCC cells and xenografts in nude mice, and inhibited hypoxia-/radiation-induced activation of STAT3 and upregulation of HIF-1? and VEGF expression. NSC74859 confers radiosensitivity in ESCC via the inhibition of STAT3 activation and the downregulation of HIF-1? and VEGF expression. NSC74859 may become a promising radiosensitizer for ESCC radiotherapy.
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Predictors of hemodynamic instability during surgery for pheochromocytoma.
Ann. Surg. Oncol.
PUBLISHED: 04-22-2014
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Resection of pheochromocytoma is often associated with hemodynamic instability (HDI). We examined patient and tumor factors that may influence HDI. The effect of pretreatment with nonselective ? blockade phenoxybenzamine (PXB) versus selective ? blockade on HDI and outcomes was also evaluated.
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Elevated hydrogen sulfide levels in vitreous body and plasma in patients with proliferative diabetic retinopathy.
Retina (Philadelphia, Pa.)
PUBLISHED: 04-19-2014
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Hydrogen sulfide (H2S), a colorless gas, has been confirmed to be a gaseous messenger molecule and an endogenous stimulus for angiogenesis recently. This study was performed to investigate the role of H2S in diabetic retinopathy.
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Melittin radiosensitizes esophageal squamous cell carcinoma with induction of apoptosis in vitro and in vivo.
Tumour Biol.
PUBLISHED: 04-16-2014
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Currently, unresectable esophageal squamous cell carcinoma (ESCC) is primarily treated by chemoradiotherapy. However, the outcome has not improved significantly because of radioresistance of cancer cells. This study aimed to determine the radiosensitizing effect of melittin, a novel component of bee venom, in ESCC. ESCC cell lines were irradiated with or without melittin. Cell proliferation was detected by Cell Counting Kit 8 assay. Radiosensitization was evaluated by clonogenic survival assay. Cell apoptosis was detected by flow cytometry. Results show that melittin potently sensitized ESCC cells to radiation with a sensitization enhancement ratio of 1.15-1.42. Radiosensitization was accompanied with enhanced apoptosis and regulated by apoptosis proteins. The results were confirmed by in vivo studies on tumor-bearing xenografts. In summary, these results provide support that melittin may be a potentially promising radiosensitizer in ESCC radiation therapy.
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Xuebijing injection improves the respiratory function in rabbits with oleic acid-induced acute lung injury by inhibiting IL-6 expression and promoting IL-10 expression at the protein and mRNA levels.
Exp Ther Med
PUBLISHED: 03-28-2014
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Xuebijing injection is a complex herbal medicine, and clinical and experimental studies have shown that it has a significant effect on acute respiratory distress syndrome and multiple organ dysfunction syndrome. However, the majority of studies regarding Xuebijing injection have focused on serum inflammatory factors, and few studies have been carried out from the perspective of the protein and mRNA expression of inflammatory cytokines. In this study, 60 healthy rabbits of mixed gender were randomly assigned to a normal control group (CG), oleic acid group (model group; MG) and oleic acid + Xuebijing injection group (treatment group; TG). Rabbits of the CG were treated with normal saline through the ear vein, rabbits of the MG were injected with oleic acid (0.4 ml/kg) and rabbits of the TG received 0.4 ml/kg oleic acid + 10 ml/kg Xuebijing injection. Blood samples were collected from the common carotid artery of all rabbits of all groups 1 h after the ear vein was injected with the corresponding reagent, and was used to measure the arterial partial pressure of oxygen (PaO2) and of carbon dioxide (PaCO2). The activity of myeloperoxidase (MPO) was tested, and the protein and mRNA expression levels of interleukin (IL)-6 and IL-10 were determined. Rabbits of the MG exhibited evident respiratory dysfunction (PaO2 and PaCO2 were low), histopathological lung damage and overactive inflammatory responses (the expression of the proinflammatory cytokine IL-6 and the anti-inflammatory cytokine IL-10 was increased at the protein and mRNA levels). Following the administration of the Xuebijing injection, the inflammatory response of the rabbits was significantly reduced. Xuebijing injection raised PaO2 and PaCO2, weakened the activity of MPO in the lung tissue, downregulated the expression of the proinflammatory cytokine IL-6 and further increased the expression of the anti-inflammatory cytokine IL-10. These results demonstrated that Xuebijing injection improved the respiratory function of rabbits with acute oleic acid-induced lung injury by inhibiting IL-6 expression and promoting IL-10 expression.
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Characterization of breast cancers with PI3K mutations in an academic practice setting using SNaPshot profiling.
Breast Cancer Res. Treat.
PUBLISHED: 03-25-2014
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Mutations in the PIK3CA gene are common in breast cancer and represent a clinically useful therapeutic target. Several larger, population-based studies have shown a positive prognostic significance associated with these mutations. This study aims to further identify characteristics of patients harboring PIK3CA mutations while evaluating the clinical impact of genomic testing for these mutations. Tumors from 312 patients at Vanderbilt-Ingram Cancer Center were analyzed for PIK3CA mutations using a multiplex screening assay (SNaPshot). Mutation rates, receptor status, histopathologic characteristics, and time to recurrence were assessed. The number of patients participating in clinical trials, specifically trials relating to the PIK3CA mutation, was examined. Statistically significant differences between wild-type and mutated tumors were determined using the Wilcoxon, Pearson, and Fischer exact tests. The PIK3CA mutation was found in 25 % of tumors tested. Patients with PIK3CA mutations were significantly more likely to express hormone receptors, be of lower combined histological grade, and have a reduced time to recurrence. Patients found to have a PIK3CA mutation were significantly more likely to enter a PIK3CA-specific clinical trial. In addition to confirming previously established positive prognostic characteristics of tumors harboring PIK3CA mutations, this study demonstrates the feasibility and utility of mutation profiling in a clinical setting. PIK3CA mutation testing impacted treatment and resulted in more patients entering mutation-specific clinical trials.
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Effects of Chinese Medicine Tong xinluo on Diabetic Nephropathy via Inhibiting TGF- ? 1-Induced Epithelial-to-Mesenchymal Transition.
Evid Based Complement Alternat Med
PUBLISHED: 03-18-2014
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Diabetic nephropathy (DN) is a major cause of chronic kidney failure and characterized by interstitial and glomeruli fibrosis. Epithelial-to-mesenchymal transition (EMT) plays an important role in the pathogenesis of DN. Tong xinluo (TXL), a Chinese herbal compound, has been used in China with established therapeutic efficacy in patients with DN. To investigate the molecular mechanism of TXL improving DN, KK-Ay mice were selected as models for the evaluation of pathogenesis and treatment in DN. In vitro, TGF- ? 1 was used to induce EMT. Western blot (WB), immunofluorescence staining, and real-time polymerase chain reaction (RT-PCR) were applied to detect the changes of EMT markers in vivo and in vitro, respectively. Results showed the expressions of TGF- ? 1 and its downstream proteins smad3/p-smad3 were greatly reduced in TXL group; meantime, TXL restored the expression of smad7. As a result, the expressions of collagen IV (Col IV) and fibronectin (FN) were significantly decreased in TXL group. In vivo, 24?h-UAER (24-hour urine albumin excretion ratio) and BUN (blood urea nitrogen) were decreased and Ccr (creatinine clearance ratio) was increased in TXL group compared with DN group. In summary, the present study demonstrates that TXL successfully inhibits TGF- ? 1-induced epithelial-to-mesenchymal transition in DN, which may account for the therapeutic efficacy in TXL-mediated renoprotection.
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Likelihood approach for evaluating bioequivalence of highly variable drugs.
Pharm Stat
PUBLISHED: 03-14-2014
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Bioequivalence (BE) is required for approving a generic drug. The two one-sided tests procedure (TOST, or the 90% confidence interval approach) has been used as the mainstream methodology to test average BE (ABE) on pharmacokinetic parameters such as the area under the blood concentration-time curve and the peak concentration. However, for highly variable drugs (%CV > 30%), it is difficult to demonstrate ABE in a standard cross-over study with the typical number of subjects using the TOST because of lack of power. Recently, the US Food and Drug Administration and the European Medicines Agency recommended similar but not identical reference-scaled average BE (RSABE) approaches to address this issue. Although the power is improved, the new approaches may not guarantee a high level of confidence for the true difference between two drugs at the ABE boundaries. It is also difficult for these approaches to address the issues of population BE (PBE) and individual BE (IBE). We advocate the use of a likelihood approach for representing and interpreting BE data as evidence. Using example data from a full replicate 2 × 4 cross-over study, we demonstrate how to present evidence using the profile likelihoods for the mean difference and standard deviation ratios of the two drugs for the pharmacokinetic parameters. With this approach, we present evidence for PBE and IBE as well as ABE within a unified framework. Our simulations show that the operating characteristics of the proposed likelihood approach are comparable with the RSABE approaches when the same criteria are applied. Copyright © 2014 John Wiley & Sons, Ltd.
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Quantitative determination and validation of avermectin B1a in commercial products using quantitative nuclear magnetic resonance spectroscopy.
Magn Reson Chem
PUBLISHED: 03-14-2014
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Nuclear magnetic resonance is defined as a quantitative spectroscopic tool that enables a precise determination of the number of substances in liquids as well as in solids. There is few report demonstrating the application of NMR in the quantification of avermectin B1a (AVB1a ); here, a proton nuclear magnetic resonance spectroscopy ((1) H NMR) using benzene [1-methoxy-4-(2-nitroethyl) (PMN)] as an internal standard and deuterochloroform as an NMR solvent was tested for the quantitative determination of AVB1a . The integrated signal of AVB1a at 5.56?ppm and the signal of PMN at 8.14?ppm in the (1) H NMR spectrum were used for quantification purposes. Parameters of specificity, linearity, accuracy, precision, intermediate precision, range, limit of detection (LOD), limit of quantification (LOQ), stability and robustness were validated. The established method was accurate and precise with good recovery (98.86%) and relative standard deviation (RSD) of assay (0.34%) within the linearity of the calibration curve ranging from 5.08 to 13.58?mg/ml (R(2) ?=?0.9999). The LOD and LOQ were 0.009 and 0.029?mg/ml, which indicated the excellent sensitivity of the method. The stability of the method was testified by a calculated RSD of 0.11%. The robustness was testified by modification of four different parameters, and the differences among each parameter were all less than 0.1%. Comparing with the assay described by the manufacturer of avermectin tablets, there was no significant difference between the assay obtained by HPLC and quantitative NMR (qNMR), which indicated qNMR was a simple and efficient method for the determination of AVB1a in commercial formulation products.
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A selective release system based on dual-drug-loaded mesoporous silica for nanoparticle-assisted combination therapy.
Chemistry
PUBLISHED: 02-24-2014
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A selective release system was demonstrated with a dual-cargo loaded MSNs. When stimulated by different signals (UV or H(+)), this system could selectively release different kinds of cargoes individually. Furthermore, this system has been used to provide a combination of chemotherapy and biotherapy for cancer treatment. This controlled release system could be an important step in the development of more effective and sophisticated nanomedicine and nanodevices, due to the possibility of selective release of a complex multi-drug.
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Selection of suitable endogenous reference genes for relative copy number detection in sugarcane.
Int J Mol Sci
PUBLISHED: 02-19-2014
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Transgene copy number has a great impact on the expression level and stability of exogenous gene in transgenic plants. Proper selection of endogenous reference genes is necessary for detection of genetic components in genetically modification (GM) crops by quantitative real-time PCR (qPCR) or by qualitative PCR approach, especially in sugarcane with polyploid and aneuploid genomic structure. qPCR technique has been widely accepted as an accurate, time-saving method on determination of copy numbers in transgenic plants and on detection of genetically modified plants to meet the regulatory and legislative requirement. In this study, to find a suitable endogenous reference gene and its real-time PCR assay for sugarcane (Saccharum spp. hybrids) DNA content quantification, we evaluated a set of potential "single copy" genes including P4H, APRT, ENOL, CYC, TST and PRR, through qualitative PCR and absolute quantitative PCR. Based on copy number comparisons among different sugarcane genotypes, including five S. officinarum, one S. spontaneum and two S. spp. hybrids, these endogenous genes fell into three groups: ENOL-3--high copy number group, TST-1 and PRR-1--medium copy number group, P4H-1, APRT-2 and CYC-2--low copy number group. Among these tested genes, P4H, APRT and CYC were the most stable, while ENOL and TST were the least stable across different sugarcane genotypes. Therefore, three primer pairs of P4H-3, APRT-2 and CYC-2 were then selected as the suitable reference gene primer pairs for sugarcane. The test of multi-target reference genes revealed that the APRT gene was a specific amplicon, suggesting this gene is the most suitable to be used as an endogenous reference target for sugarcane DNA content quantification. These results should be helpful for establishing accurate and reliable qualitative and quantitative PCR analysis of GM sugarcane.
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Combined effect of nerve growth factor and brain?derived neurotrophic factor on neuronal differentiation of neural stem cells and the potential molecular mechanisms.
Mol Med Rep
PUBLISHED: 02-14-2014
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Neural stem cells (NSCs) are important pluripotent stem cells, which have potential applications in cell replacement therapy. Brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) have been demonstrated to exert a marked impact on the proliferation and differentiation of NSCs. The effects of NGF, BDNF, and BDNF combined with NGF on NSC neuronal differentiation and the possible mechanisms for these effects were investigated in this study. An adherent monolayer culture was employed to obtain highly homogeneous NSCs. The cells were divided into four groups: Control, NGF, BDNF and combination (BDNF + NGF) groups. Neuron differentiation was examined using immunocytochemistry and phospho-extracellular signal-regulated kinase (p?ERK) levels were analyzed using western blotting. Reverse transcription polymerase chain reaction was used to measure the mRNA expression levels of the HES1, HES5, MASH1, NGN1 and NeuroD transcription factors at different time intervals following neurotrophin-induced differentiation. NGF and BDNF were observed to induce NSC neuronal differentiation, and ?-tubulin III-positive cells and p-ERK expression levels were highest in the NGF + BDNF combination group at all time points. The proportion of ?-tubulin ?-positive neurons in each group was associated with the expression levels of MASH1, NGN1 and NeuroD in the group. In conclusion, BDNF combined with NGF significantly improved NSC neuronal differentiation, which may provide support for the practical application of NSCs in neurodegenerative diseases.
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Exome sequencing reveals CHM mutations in six families with atypical choroideremia initially diagnosed as retinitis pigmentosa.
Int. J. Mol. Med.
PUBLISHED: 02-14-2014
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Mutations in almost 200 genes are associated with hereditary retinal diseases. Of these diseases, retinitis pigmentosa (RP) is the most common and is genetically and clinically highly heterogeneous. At least 62 genes are associated with RP and mutations in these genes account for approximately half of the cases of disease. In the present study, mutations in the CHM gene, which are known to associate with choroideremia, were identified in six of 157 families with retinitis pigmentosa by whole exome sequencing. No potential pathogenic mutations in the 62 RP?associated genes were found in the six families. Sanger sequencing confirmed the mutations in CHM, including four novel (c.558_559delTT, c.964G>T, c.966delA, c.1166+2T>G) and two known (c.703?1G>A and c.1584_1587delTGTT) mutations. Available clinical data suggest an atypical phenotype of choroideremia in these patients compared to that of Caucasians. Overlapping clinical features and atypical phenotypic variation may contribute to the confusion of one another. Awareness of the phenotypic variation and careful clinical examination may facilitate proper clinical diagnosis and genetic counseling of complicated hereditary retinal diseases. Whole exome sequencing therefore is useful in the identification of genetic cause for less clarified hereditary retinal diseases and enriches our understanding of phenotypic variations of gene mutation.
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Cultivar evaluation and essential test locations identification for sugarcane breeding in China.
ScientificWorldJournal
PUBLISHED: 02-07-2014
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The discrepancies across test sites and years, along with the interaction between cultivar and environment, make it difficult to accurately evaluate the differences of the sugarcane cultivars. Using a genotype main effect plus genotype-environment interaction (GGE) Biplot software, the yield performance data of seven sugarcane cultivars in the 8th Chinese National Sugarcane Regional Tests were analyzed to identify cultivars recommended for commercial release. Fn38 produced a high and stable sugar yield. Gn02-70 had the lowest cane yield with high stability. Yz06-407 was a high cane yield cultivar with poor stability in sugar yield. Yz05-51 and Lc03-1137 had an unstable cane yield but relatively high sugar yield. Fn39 produced stable high sugar yield with low and unstable cane production. Significantly different sugar and cane yields were observed across seasons due to strong cultivar-environment interactions. Three areas, Guangxi Chongzuo, Guangxi Baise, and Guangxi Hechi, showed better representativeness of cane yield and sugar content than the other four areas. On the other hand, the areas Guangxi Chongzuo, Yunnan Lincang, and Yunnan Baoshan showed strong discrimination ability, while the areas Guangxi Hechi and Guangxi Liuzhou showed poor discrimination ability. This study provides a reference for cultivar evaluation and essential test locations identification for sugarcane breeding in China.
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High-level coproduction, purification and characterisation of laccase and exopolysaccharides by Coriolus versicolor.
Food Chem
PUBLISHED: 02-05-2014
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In this study, a two-stage pH-shift fermentation process was developed for the coproduction of laccase and exopolysaccharides (EPS) by Coriolus versicolor. At the same time, laccase and EPS were purified and characterised in detail. The results showed that the highest laccase and EPS production reached 7680 U l(-1) and 8.2 g l(-1). Furthermore, the flow behaviour of fermentation broth was Newtonian and the maximum ?(ap) was 2.7×10(-3) Pa s. The MW of laccase was 64 kDa and it showed a pI value of 4.2. The CD analysis showed that laccase had a high ?-helical content (68%). The MW of the purified EPS was determined to be 1.8×10(6) Da, consisting of carbohydrates (87.6%) and proteins (12.4%). The EPS consisted of 17 amino acids, mainly serine (11.3%), glutamic acid (12.60%), leucine (13.3%) and phenylalanine (9.4%) in protein moiety, and three monosaccharides (galactose, mannose and xylose).
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Mechanism, reactivity, and selectivity in palladium-catalyzed redox-relay Heck arylations of alkenyl alcohols.
J. Am. Chem. Soc.
PUBLISHED: 01-22-2014
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The enantioselective Pd-catalyzed redox-relay Heck arylation of acyclic alkenyl alcohols allows access to various useful chiral building blocks from simple olefinic substrates. Mechanistically, after the initial migratory insertion, a succession of ?-hydride elimination and migratory insertion steps yields a saturated carbonyl product instead of the more general Heck product, an unsaturated alcohol. Here, we investigate the reaction mechanism, including the relay function, yielding the final carbonyl group transformation. M06 calculations predict a ??G(‡) of 1 kcal/mol for the site selectivity and 2.5 kcal/mol for the enantioselectivity, in quantitative agreement with experimental results. The site selectivity is controlled by a remote electronic effect, where the developing polarization of the alkene in the migratory insertion transition state is stabilized by the C-O dipole of the alcohol moiety. The enantioselectivity is controlled by steric repulsion between the oxazoline substituent and the alcohol-bearing alkene substituent. The relay efficiency is due to an unusually smooth potential energy surface without high barriers, where the hydroxyalkyl-palladium species acts as a thermodynamic sink, driving the reaction toward the carbonyl product. Computational predictions of the relative reactivity and selectivity of the double bond isomers are validated experimentally.
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Establishment and application of a loop-mediated isothermal amplification (LAMP) system for detection of cry1Ac transgenic sugarcane.
Sci Rep
PUBLISHED: 01-20-2014
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To meet the demand for detection of foreign genes in genetically modified (GM) sugarcane necessary for regulation of gene technology, an efficient method with high specificity and rapidity was developed for the cry1Ac gene, based on loop-mediated isothermal amplification (LAMP). A set of four primers was designed using the sequence of cry1Ac along with optimized reaction conditions: 5.25?mM of Mg(2+), 4:1 ratio of inner primer to outer primer, 2.0?U of Bst DNA polymerase in a reaction volume of 25.0??L. Three post-LAMP detection methods (precipitation, calcein (0.60?mM) with Mn(2+) (0.05?mM) complex and SYBR Green I visualization), were shown to be effective. The sensitivity of the LAMP method was tenfold higher than that of conventional PCR when using templates of the recombinant cry1Ac plasmid or genomic DNA from cry1Ac transgenic sugarcane plants. More importantly, this system allowed detection of the foreign gene on-site when screening GM sugarcane without complex and expensive instruments, using the naked eye. This method can not only provide technological support for detection of cry1Ac, but can also further facilitate the use of this detection technique for other transgenes in GM sugarcane.
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Photosynthetic and canopy characteristics of different varieties at the early elongation stage and their relationships with the cane yield in sugarcane.
ScientificWorldJournal
PUBLISHED: 01-15-2014
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During sugarcane growth, the Early Elongation stage is critical to cane yield formation. In this study, parameters of 17 sugarcane varieties were determined at the Early Elongation stage using CI-301 photosynthesis measuring system and CI-100 digital plant canopy imager. The data analysis showed highly significant differences in leaf area index (LAI), mean foliage inclination angle (MFIA), transmission coefficient for diffused light penetration (TD), transmission coefficient for solar beam radiation penetration (TR), leaf distribution (LD), net photosynthetic rate (PN), transpiration rate (E), and stomatal conductance (GS) among sugarcane varieties. Based on the photosynthetic or canopy parameters, the 17 sugarcane varieties were classified into four categories. Through the factor analysis, nine parameters were represented by three principal factors, of which the cumulative rate of variance contributions reached 85.77%. A regression for sugarcane yield, with relative error of yield fitting less than 0.05, was successfully established: sugarcane yield = -27.19 - 1.69 × PN + 0.17 × E + 90.43 × LAI - 408.81 × LD + 0.0015 × NSH + 101.38 × D (R(2) = 0.928**). This study helps provide a theoretical basis and technical guidance for the screening of new sugarcane varieties with high net photosynthetic rate and ideal canopy structure.
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New phenotypic characteristics of three tmm alleles in Arabidopsis thaliana.
Plant Cell Rep.
PUBLISHED: 01-15-2014
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Three new tmm mutants were isolated and showed differential phenotypes from tmm - 1 , and TMM overexpression led to abnormal leaf trichomes. TOO MANY MOUTH (TMM) plays a significant role in the stomatal signal transduction pathway, which involves in the regulation of stomatal distribution and patterning. Three mutants with clustered stomata were isolated and identified as new alleles of tmm. tmm-4 mutation included a base transversion from adenine to thymidine in position 1,033 of the TMM coding region and resulted in premature termination of translation at position 345 of TMM. tmm-5 had a base transition from cytosine to thymidine in 244 of TMM and translated 82 amino acids before premature termination. tmm-6 mutation took a base transition from guanine to adenine in 463 of TMM and changed a glycine (Gly) to an arginine (Arg) in position 155 of the protein. tmm-6 had an evident reduction of stomatal clusters and fewer stomata in cluster compared with other tmm alleles, possibly due to decreased level of entry divisions in cells next to two stomata or their precursors. tmm-5 and tmm-6 were hypersensitive to abscisic acid (ABA) in seedling growth and seed germination, while tmm-4 was defective in response to ABA during seed dormancy, suggesting that TMM was involved in ABA signaling transduction. Interestingly, overexpression of TMM resulted in the reduction of leaf trichomes and their branches, and this might reveal a new function of TMM in trichome development.
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ScChi, encoding an acidic class III chitinase of sugarcane, confers positive responses to biotic and abiotic stresses in sugarcane.
Int J Mol Sci
PUBLISHED: 01-13-2014
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Chitinases (EC 3.2.2.14), expressed during the plant-pathogen interaction, are associated with plant defense against pathogens. In the present study, a positive correlation between chitinase activity and sugarcane smut resistance was found. ScChi (GenBank accession no. KF664180), a Class III chitinase gene, encoded a 31.37 kDa polypeptide, was cloned and identified. Subcellular localization revealed ScChi targeting to the nucleus, cytoplasm and the plasma membrane. Real-time quantitative PCR (RT-qPCR) results showed that ScChi was highly expressed in leaf and stem epidermal tissues. The ScChi transcript was both higher and maintained longer in the resistance cultivar during challenge with Sporisorium scitamineum. The ScChi also showed an obvious induction of transcription after treatment with SA (salicylic acid), H2O2, MeJA (methyl jasmonate), ABA (abscisic acid), NaCl, CuCl2, PEG (polyethylene glycol) and low temperature (4 °C). The expression levels of ScChi and six immunity associated marker genes were upregulated by the transient overexpression of ScChi. Besides, histochemical assay of Nicotiana benthamiana leaves overexpressing pCAMBIA 1301-ScChi exhibited deep DAB (3,3'-diaminobenzidinesolution) staining color and high conductivity, indicating the high level of H2O2 accumulation. These results suggest a close relationship between the expression of ScChi and plant immunity. In conclusion, the positive responses of ScChi to the biotic and abiotic stimuli reveal that this gene is a stress-related gene of sugarcane.
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The tetratricopeptide repeat-containing protein slow green1 is required for chloroplast development in Arabidopsis.
J. Exp. Bot.
PUBLISHED: 01-13-2014
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A new gene, SG1, was identified in a slow-greening mutant (sg1) isolated from an ethylmethanesulphonate-mutagenized population of Arabidopsis thaliana. The newly formed leaves of sg1 were initially albino, but gradually became pale green. After 3 weeks, the leaves of the mutant were as green as those of the wild-type plants. Transmission electron microscopic observations revealed that the mutant displayed delayed proplastid to chloroplast transition. The results of map-based cloning showed that SG1 encodes a chloroplast-localized tetratricopeptide repeat-containing protein. Quantitative real-time reverse transcription-PCR data demonstrated the presence of SG1 gene expression in all tissues, particularly young green tissues. The sg1 mutation disrupted the expression levels of several genes associated with chloroplast development, photosynthesis, and chlorophyll biosynthesis. The results of genetic analysis indicated that gun1 and gun4 partially restored the expression patterns of the previously detected chloroplast-associated genes, thereby ameliorating the slow-greening phenotype of sg1. Taken together, the results suggest that the newly identified protein, SG1, is required for chloroplast development in Arabidopsis.
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Mutations of 60 known causative genes in 157 families with retinitis pigmentosa based on exome sequencing.
Hum. Genet.
PUBLISHED: 01-07-2014
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Retinitis pigmentosa (RP) is the most common and highly heterogeneous form of hereditary retinal degeneration. This study was to identify mutations in the 60 genes that were known to be associated with RP in 157 unrelated Chinese families with RP. Genomic DNA from probands was initially analyzed by whole exome sequencing. Sanger sequencing was used to confirm potential candidate variants affecting the encoded residues in the 60 genes, including heterozygous variants from genes that are related to autosomal dominant RP, homozygous or compound heterozygous variants from genes that are related to autosomal recessive RP, and hemizygous variants from genes that are related to X-linked RP. Synonymous and intronic variants were also examined to confirm whether they could affect splicing. A total of 244 candidate variants were detected by exome sequencing. Sanger sequencing confirmed 240 variants out of the 244 candidates. Informatics and segregation analyses suggested 110 potential pathogenic mutations in 28 out of the 60 genes involving 79 of the 157 (50%) families, including 31 (39%, 31/79) families with heterozygous mutations in autosomal dominant genes, 37 (47%, 37/79) families with homozygous (9) or compound heterozygous (28) mutations in autosomal recessive genes, and 11 (14%, 11/79) families with hemizygous mutations in X-linked genes. Of the 110 identified variants, 74 (67%) were novel. The genetic defects in approximately half of the 157 studies families were detected by exome sequencing. A comprehensive analysis of the 60 known genes not only expanded the mutation spectrum and frequency of the 60 genes in Chinese patients with RP, but also provided an overview of the molecular etiology of RP in Chinese patients. The analysis of the known genes also supplied the foundation and clues for discovering novel causative RP genes.
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Leptin level and oxidative stress contribute to obesity-induced low testosterone in murine testicular tissue.
Oxid Med Cell Longev
PUBLISHED: 01-07-2014
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This study evaluated the effects of obesity on the function of reproductive organs in male mice and the possible mechanism of male secondary hypogonadism (SH) in obesity.
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Genetic analysis of diversity within a Chinese local sugarcane germplasm based on start codon targeted polymorphism.
Biomed Res Int
PUBLISHED: 01-03-2014
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In-depth information on sugarcane germplasm is the basis for its conservation and utilization. Data on sugarcane molecular markers are limited for the Chinese sugarcane germplasm collections. In the present study, 20 start codon targeted (SCoT) marker primers were designed to assess the genetic diversity among 107 sugarcane accessions within a local sugarcane germplasm collection. These primers amplified 176 DNA fragments, of which 163 were polymorphic (92.85%). Polymorphic information content (PIC) values ranged from 0.783 to 0.907 with a mean of 0.861. Unweighted pair group method of arithmetic averages (UPGMA) cluster analysis of the SCoT marker data divided the 107 sugarcane accessions into six clusters at 0.674 genetic similarity coefficient level. Relatively abundant genetic diversity was observed among ROC22, ROC16, and ROC10, which occupied about 80% of the total sugarcane acreage in China, indicating their potential breeding value on Mainland China. Principal component analysis (PCA) partitioned the 107 sugarcane accessions into two major groups, the Domestic Group and the Foreign Introduction Group. Each group was further divided based on institutions, where the sugarcane accessions were originally developed. The knowledge of genetic diversity among the local sugarcane germplasm provided foundation data for managing sugarcane germplasm, including construction of a core collection and regional variety distribution and subrogation.
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Thymidylate synthase genotype-directed chemotherapy for patients with gastric and gastroesophageal junction cancers.
PLoS ONE
PUBLISHED: 01-01-2014
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Retrospective studies indicate associations between TSER (thymidylate synthase enhancer region) genotypes and clinical outcomes in patients receiving 5-FU based chemotherapy, but well-controlled prospective validation has been lacking.
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Separation of metabolic supply and demand: aerobic glycolysis as a normal physiological response to fluctuating energetic demands in the membrane.
Cancer Metab
PUBLISHED: 01-01-2014
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Cancer cells, and a variety of normal cells, exhibit aerobic glycolysis, high rates of glucose fermentation in the presence of normal oxygen concentrations, also known as the Warburg effect. This metabolism is considered abnormal because it violates the standard model of cellular energy production that assumes glucose metabolism is predominantly governed by oxygen concentrations and, therefore, fermentative glycolysis is an emergency back-up for periods of hypoxia. Though several hypotheses have been proposed for the origin of aerobic glycolysis, its biological basis in cancer and normal cells is still not well understood.
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Isolation and characterization of microsatellite markers and analysis of genetic diversity in Chinese jujube (Ziziphus jujuba Mill.).
PLoS ONE
PUBLISHED: 01-01-2014
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Chinese jujube (Ziziphus jujuba Mill, 2n = 2× = 24, Rhamnaceae) is an economically important Chinese native species. It has high nutritional value, and its medicinal properties have led to extensive use in traditional oriental medicine. The characterization of genotypes using molecular markers is important for genetic studies and plant breeding. However, few simple sequence repeat (SSR) markers are available for this species. In this study, 1,488 unique SSR clones were isolated from Z. jujuba 'Dongzao' using enriched genomic libraries coupled with a three-primer colony PCR screening strategy, yielding a high enrichment rate of 73.3%. Finally, 1,188 (80.87%) primer pairs were amplified successfully in the size expected for 'Dongzao'. A total of 350 primer pairs were further selected and evaluated for their ability to detect polymorphisms across a panel of six diverse cultivars; among these, 301 primer pairs detected polymorphisms, and the polymorphism information content (PIC) value across all loci ranged from 0.15 to 0.82, with an average of 0.52. An analysis of 76 major cultivars employed in Chinese jujube production using 31 primer pairs revealed comparatively high genetic diversity among these cultivars. Within-population differences among individuals accounted for 98.2% of the observed genetic variation. Neighbor-joining clustering divided the cultivars into three main groups, none of which correspond to major geographic regions, suggesting that the genetics and geographical origin of modern Chinese jujube cultivars might not be linked. The current work firstly reports the large-scale development of Chinese jujube SSR markers. The development of these markers and their polymorphic information represent a significant improvement in the available Chinese jujube genomic resources and will facilitate both genetic and breeding applications, further accelerating the development of new cultivars.
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PARP-1 Val762Ala polymorphism and risk of cancer: a meta-analysis based on 39 case-control studies.
PLoS ONE
PUBLISHED: 01-01-2014
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Poly(ADP-ribose) polymerase-1 (PARP-1) is a nuclear chromatin-associated enzyme involved in several important cellular processes, particularly in the DNA repair system. PARP-1 rs1136410: C>T is among the most studied polymorphisms and likely involved in human carcinogenesis. However, results from previous studies are inconclusive. Thus, a meta-analysis was conducted to derive a more precise estimation of the effects of this enzyme.
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A novel DFNA36 mutation in TMC1 orthologous to the Beethoven (Bth) mouse associated with autosomal dominant hearing loss in a Chinese family.
PLoS ONE
PUBLISHED: 01-01-2014
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Mutations in the transmembrane channel-like gene 1 (TMC1) can cause both DFNA36 and DFNB7/11 hearing loss. More than thirty DFNB7/11 mutations have been reported, but only three DFNA36 mutations were reported previously. In this study, we found a large Chinese family with 222 family members showing post-lingual, progressive sensorineural hearing loss which were consistent with DFNA36 hearing loss. Auditory brainstem response (ABR) test of the youngest patient showed a special result with nearly normal threshold but prolonged latency, decreased amplitude, and the abnormal waveform morphology. Exome sequencing of the proband found four candidate variants in known hearing loss genes. Sanger sequencing in all family members found a novel variant c.1253T>A (p.M418K) in TMC1 at DFNA36 that co-segregated with the phenotype. This mutation in TMC1 is orthologous to the mutation found in the hearing loss mouse model named Bth ten years ago. In another 51 Chinese autosomal dominant hearing loss families, we screened the segments containing the dominant mutations of TMC1 and no functional variants were found. TMC1 is expressed in the hair cells in inner ear. Given the already known roles of TMC1 in the mechanotransduction in the cochlea and its expression in inner ear, our results may provide an interesting perspective into its function in inner ear.
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Comprehensive selection of reference genes for gene expression normalization in sugarcane by real time quantitative rt-PCR.
PLoS ONE
PUBLISHED: 01-01-2014
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The increasingly used real time quantitative reverse transcription-PCR (qRT-PCR) method for gene expression analysis requires one or several reference gene(s) acting as normalization factor(s). In order to facilitate gene expression studies in sugarcane (Saccharum officinarum), a non-model plant with limited genome information, the stability of 13 candidate reference genes was evaluated. The geNorm, NormFinder and deltaCt methods were used for selecting stably expressed internal controls across different tissues and under various experimental treatments. These results revealed that, among these 13 candidate reference genes, GAPDH, eEF-1a and eIF-4? were the most stable and suitable for use as normalization factors across all various experimental samples. In addition, APRT could be a candidate for examining the relationship between gene copy number and transcript levels in sugarcane tissue samples. According to the results evaluated by geNorm, combining CUL and eEF-1? in hormone treatment experiments; CAC and CUL in abiotic stress tests; GAPDH, eEF-1a and CUL in all treatment samples plus CAC, CUL, APRT and TIPS-41 in cultivar tissues as groups for normalization would lead to more accurate and reliable expression quantification in sugarcane. This is the first systematic validation of reference genes for quantification of transcript expression profiles in sugarcane. This study should provide useful information for selecting reference genes for more accurate quantification of gene expression in sugarcane and other plant species.
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A functional variant of PTPN22 confers risk for Vogt-Koyanagi-Harada syndrome but not for ankylosing spondylitis.
PLoS ONE
PUBLISHED: 01-01-2014
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Protein tyrosine phosphatase non-receptor 22 (PTPN22) is a key negative regulator of T lymphocytes and has emerged as an important candidate susceptibility factor for a number of immune-related diseases. This study aimed to examine the predisposition of PTPN22 SNPs to Vogt-Koyanagi-Harada (VKH) syndrome and acute anterior uveitis (AAU) associated with ankylosing spondylitis (AS).
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Biogeographical variation and population genetic structure of Sporisorium scitamineum in Mainland China: insights from ISSR and SP-SRAP markers.
ScientificWorldJournal
PUBLISHED: 01-01-2014
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A total of 100 Sporisorium scitamineum isolates were investigated by inter simple sequence repeat (ISSR) and single primer-sequence related amplified polymorphism (SP-SRAP) markers. These isolates were clearly assorted into three distinct clusters regardless of method used: either cluster analysis or by principal component analysis (PCA) of the ISSR, SP-SRAP, or ISSR + SP-SRAP data set. The total gene diversity (H t) and gene diversity between subpopulations (H s) were estimated to be 0.34 to 0.38 and 0.22 to 0.29, respectively, by analyzing separately the ISSR and SP-SRAP data sets, and to be 0.26-0.36 by analyzing ISSR + SP-SRAP data set. The gene diversity attributable to differentiation among populations (G st) was estimated to be 0.35 and 0.22, and the gene flow (Nm) was 0.94 and 1.78, respectively, when analyzing separately ISSR and SP-SRAP data set, and was 0.27 and 1.33, respectively, when analyzing ISSR + SP-SRAP data set. Our study showed that there is considerable genetic variation in the analyzed 100 isolates, and the environmental heterogeneity has played an important role for this observed high degree of variation. The genetic differentiation of sugarcane smut fungus depends to a large extent on the heterogeneity of their habitats and is the result of long-term adaptations of pathogens to their ecological environments.
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The role of interleukin-1 receptor-associated kinases in Vogt-Koyanagi-Harada disease.
PLoS ONE
PUBLISHED: 01-01-2014
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To explore whether IRAK1 and IRAK4 are involved in the pathogenesis of Vogt-Koyanagi-Harada (VKH) disease.
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The application of quantitative NMR for the facile, rapid and reliable determination of clindamycin phosphate in a conventional tablet formulation.
Magn Reson Chem
PUBLISHED: 01-01-2014
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Spectroscopic tools such as NMR can be applied to the quantitative analysis of active pharmaceutical ingredients with relative ease and accuracy. Here, we demonstrate the quantification of clindamycin phosphate (CLP) in a conventional tablet formulation, performed using potassium hydrogen phthalate (KHP) as the internal standard and deuterium oxide (D2O) as the NMR solvent. The methyl protons signal of CLP at 0.72 ppm (triplet) relative to the signal of KHP at 7.37-7.40 ppm (multiplet) was used for quantification purposes using (1)H NMR. This method was shown to be specific and linear (r = 0.9997) within the CLP concentration range from 7.2 to 23.1 mg per 0.5 ml of D2O. The maximum relative standard deviation (RSD) of accuracy and precision was calculated at 0.39% and 0.64%, respectively. The limits of detection (LOD) and quantification were 0.04 and 0.11 mg/ml, respectively. The method was highly stable with a calculated RSD of 0.03%. The robustness of the method was demonstrated by changing four different parameters, and the difference among each parameter was ? 0.78%. The findings of this work were in good agreement with previously reported conventional HPLC-based approaches, highlighting its applicability in the determination of other active pharmaceutical ingredients in conventional formulations for quality control purposes.
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Isolation of a novel peroxisomal catalase gene from sugarcane, which is responsive to biotic and abiotic stresses.
PLoS ONE
PUBLISHED: 01-01-2014
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Catalase is an iron porphyrin enzyme, which serves as an efficient scavenger of reactive oxygen species (ROS) to avoid oxidative damage. In sugarcane, the enzymatic activity of catalase in a variety (Yacheng05-179) resistant to the smut pathogen Sporisorium scitamineum was always higher than that of the susceptible variety (Liucheng03-182), suggesting that catalase activity may have a positive correlation with smut resistance in sugarcane. To understand the function of catalase at the molecular level, a cDNA sequence of ScCAT1 (GenBank Accession No. KF664183), was isolated from sugarcane infected by S. scitamineum. ScCAT1 was predicted to encode 492 amino acid residues, and its deduced amino acid sequence shared a high degree of homology with other plant catalases. Enhanced growth of ScCAT1 in recombinant Escherichia coli Rosetta cells under the stresses of CuCl2, CdCl2 and NaCl indicated its high tolerance. Q-PCR results showed that ScCAT1 was expressed at relatively high levels in the bud, whereas expression was moderate in stem epidermis and stem pith. Different kinds of stresses, including S. scitamineum challenge, plant hormones (SA, MeJA and ABA) treatments, oxidative (H2O2) stress, heavy metal (CuCl2) and hyper-osmotic (PEG and NaCl) stresses, triggered a significant induction of ScCAT1. The ScCAT1 protein appeared to localize in plasma membrane and cytoplasm. Furthermore, histochemical assays using DAB and trypan blue staining, as well as conductivity measurement, indicated that ScCAT1 may confer the sugarcane immunity. In conclusion, the positive response of ScCAT1 to biotic and abiotic stresses suggests that ScCAT1 is involved in protection of sugarcane against reactive oxidant-related environmental stimuli.
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Gsta4 Null Mouse Embryonic Fibroblasts Exhibit Enhanced Sensitivity to Oxidants: Role of 4-Hydroxynonenal in Oxidant Toxicity.
Open J Apoptosis
PUBLISHED: 12-20-2013
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The alpha class glutathione s-transferase (GST) isozyme GSTA4-4 (EC2.5.1.18) exhibits high catalytic efficiency to-wards 4-hydroxynon-2-enal (4-HNE), a major end product of oxidative stress induced lipid peroxidation. Exposure of cells and tissues to heat, radiation, and chemicals has been shown to induce oxidative stress resulting in elevated concentrations of 4-HNE that can be detrimental to cell survival. Alternatively, at physiological levels 4-HNE acts as a signaling molecule conveying the occurrence of oxidative events initiating the activation of adaptive pathways. To examine the impact of oxidative/electrophilic stress in a model with impaired 4-HNE metabolizing capability, we disrupted the Gsta4 gene that encodes GSTA4-4 in mice. The effect of electrophile and oxidants on embryonic fibroblasts (MEF) isolated from wild type (WT) and Gsta4 null mice were examined. Results indicate that in the absence of GSTA4-4, oxidant-induced toxicity is potentiated and correlates with elevated accumulation of 4-HNE adducts and DNA damage. Treatment of Gsta4 null MEF with 1,1,4-tris(acetyloxy)-2(E)-nonene [4-HNE(Ac)3], a pro-drug form of 4-HNE, resulted in the activation and phosphorylation of the c-jun-N-terminal kinase (JNK), extracellular-signal-regulated kinases (ERK 1/2) and p38 mitogen activated protein kinases (p38 MAPK) accompanied by enhanced cleavage of caspase-3. Interestingly, when recombinant mammalian or invertebrate GSTs were delivered to Gsta4 null MEF, activation of stress-related kinases in 4-HNE(Ac)3 treated Gsta4 null MEF were inversely correlated with the catalytic efficiency of delivered GSTs towards 4-HNE. Our data suggest that GSTA4-4 plays a major role in protecting cells from the toxic effects of oxidant chemicals by attenuating the accumulation of 4-HNE.
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Berberine radiosensitizes human nasopharyngeal carcinoma by suppressing hypoxia-inducible factor-1? expression.
Acta Otolaryngol.
PUBLISHED: 12-10-2013
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Abstract Conclusion: Berberine confers radiosensitivity on nasopharyngeal carcinoma (NPC) and this is associated with the down-regulation of hypoxia-inducible factor-1? (HIF-1?) and vascular endothelial growth factor (VEGF) expression. Berberine could be a promising radiosensitizer for NPC radiotherapy. Objectives: NPC has a poor prognosis. Radiotherapy as first-line therapy significantly increases patient survival but radioresistance is a problem. This study aimed to investigate the radiosensitizing effects of berberine on NPC and explore the underlying mechanisms. Methods: CNE-1 and CNE-2 cells were exposed to hypoxia and treated with berberine at different concentrations. The MTT assay, clonogenic assay, and flow cytometry were performed to analyze cell proliferation, colony formation, and apoptosis. The expression of HIF-1? and VEGF was assessed by Western blot and immunofluorescence analysis. Male nude mice inoculated subcutaneously with CNE-2 cells were used to examine the sensitizing effects of berberine in vivo. Results: Berberine efficiently radiosensitized NPC cells and xenografts in mice, and inhibited hypoxia/radiation-induced up-regulation of HIF-1? and VEGF expression.
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Effects of walking on the preservation of bone mineral density in perimenopausal and postmenopausal women: a systematic review and meta-analysis.
Menopause
PUBLISHED: 10-24-2013
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This study aims to critically evaluate the effects of a walking intervention on bone mineral density (BMD) in perimenopausal and postmenopausal women and to identify the optimal duration of this walking exercise intervention.
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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.