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Elevated CO2 can affect the synthesis and distribution of photosynthetic assimilates. However, the carbohydrate metabolism molecular mechanism of cucumber leaves in response to CO2 enrichment is unclear. Therefore, it is of great significance to investigate the key functional regulatory genes in cucumber. In this study, the growth of cucumber leaves under different CO2 conditions was compared. The results showed that under CO2 enrichment, leaf area increased, the number of mesophyll cells increased, stomata enlarged, and more starch grains accumulated in the chloroplasts. Compared with the control, the starch and soluble sugar content of leaves were maximally increased by 194.1% and 55.94%, respectively; the activities of fructose-1,6-bisphosphatase (FBPase), ADPG pyrophosphorylase (AGPase), starch synthase (SSS), sucrose phosphate synthase (SPS), sucrose synthase (SS) and invertase (Inv) were maximally increased by 36.91%, 66.13%, 33.18%, 21.7%, 54.11%, and 46.01%, respectively. Through transcriptome analysis, a total of 1,582 differential expressed genes (DEGs) were identified, in which the starch and sucrose metabolism pathway was significantly enriched, and 23 genes of carbon metabolism were screened. Through metabolome analysis, a total of 22 differential accumulation metabolites (DAMs) were identified. Moreover, D-glucose and D(+)-glucose were significantly accumulated, showing upregulation 2.4-fold and 2.6-fold, respectively. Through combined analysis of transcriptome and metabolome, it was revealed that seven genes were highly related to D-glucose, and Csa6G153460 (AGPase), Csa5G612840 (ß-glucosidase), and Csa4G420150 (4-α-glucanotransferase) were significantly correlated to the carbohydrate regulatory network. Furthermore, the mechanism of CO2 enrichment that promotes carbohydrate metabolism in leaves at the molecular level was revealed. This mechanism advances the development of the cell wall and leaf morphology by activating the expression of key genes and improving enzyme activity.
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Metabolismo dos Carboidratos , Dióxido de Carbono , Cucumis sativus , Regulação da Expressão Gênica de Plantas , Folhas de Planta , Folhas de Planta/metabolismo , Cucumis sativus/metabolismo , Cucumis sativus/genética , Cucumis sativus/crescimento & desenvolvimento , Dióxido de Carbono/metabolismo , Amido/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Sacarose/metabolismo , Fotossíntese , Perfilação da Expressão Gênica , TranscriptomaRESUMO
OBJECTIVES: To investigate whether miR-1260b can regulate migration and invasion of hepatocellular carcinoma (HCC) by targeting RGS22. RESULTS: miR-1260b was up-regulated in HCC tissues compared with their corresponding non-cancerous tissues. Over-expression of miR-1260b increased migration and invasion of HepG2 and SMMC-7721 cells associated with HCC. Regulator of G-protein signaling 22 (RGS22) was identified as a directly target of miR-1260b and was inhibited by miR-1260b. Knockdown of RGS22 increased proliferation of HCC cells. CONCLUSIONS: The new identified miR-1260b/RGS22 axis provides useful therapeutic methods for treatment of HCC deepening on our understanding of underlying mechanisms of HCC tumorigenesis.
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Antígenos de Superfície/metabolismo , Carcinoma Hepatocelular/patologia , Movimento Celular , Proliferação de Células , Reguladores de Proteínas de Ligação ao GTP/metabolismo , Neoplasias Hepáticas/patologia , MicroRNAs/metabolismo , Carcinoma Hepatocelular/fisiopatologia , Células Hep G2 , Humanos , Neoplasias Hepáticas/fisiopatologia , Transdução de SinaisRESUMO
Four non-fluorinated sulfonimide polyamides (s-PAs) were successfully synthesized and a series of membranes were prepared by blending s-PA with polyvinylidene fluoride (PVDF) to achieve high-methanol-permeation resistivity for direct methanol fuel cell (DMFC) applications. Four membranes were fabricated by blending 50 wt% PVDF with s-PA, named BPD-101, BPD-102, BPD-111 and BPD-211, respectively. The s-PA/PVDF membranes exhibit high methanol resistivity, especially for the BPD-111 membrane with methanol resistivity of 8.13 × 10-7 cm2/s, which is one order of magnitude smaller than that of the Nafion 117 membrane. The tensile strength of the BPD-111 membrane is 15 MPa, comparable to that of the Nafion 117 membrane. Moreover, the four membranes also show good thermal stability up to 230 °C. The BPD-x membrane exhibits good oxidative stability, and the measured residual weights of the BPD-111 membrane are 97% and 93% after treating in Fenton's reagent (80 °C) for 1 h and 24 h, respectively. By considering the mechanical, thermal and dimensional properties, the polyamide proton-exchange membrane exhibits promising application potential for direct methanol fuel cells.
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BACKGROUND: Neither HBV DNA nor HBsAg positivity at birth is an accurate marker for HBV infection of infants. No data is available for continuous changes of HBV markers in newborns to HBsAg(+) mothers. This prospective, multi-centers study aims at observing the dynamic changes of HBV markers and exploring an early diagnostic marker for mother-infant infection. METHODS: One hundred forty-eight HBsAg(+) mothers and their newborns were enrolled after mothers signed the informed consent forms. Those infants were received combination immunoprophylaxis (hepatitis B immunoglobulin [HBIG] and hepatitis B vaccine) at birth, and then followed up to 12 months. Venous blood of the infants (0, 1, 7, and 12 months of age) was collected to test for HBV DNA and HBV markers. RESULTS: Of the 148 infants enrolled in our study, 41 and 24 infants were detected as HBsAg(+) and HBV DNA(+) at birth, respectively. Nine were diagnosed with HBV infection after 7 mo follow-up. Dynamic observation of the HBV markers showed that HBV DNA and HBsAg decreased gradually and eventually sero-converted to negativity in the non-infected infants, whereas in the infected infants, HBV DNA and HBsAg were persistently positive, or higher at the end of follow-up. At 1 mo, the infants with anti-HBs(+), despite positivity for HBsAg or HBV DNA at birth, were resolved after 12 mo follow-up, whereas all the nine infants with anti-HBs(-) were diagnosed with HBV infection. Anti-HBs(-) at 1 mo showed a higher positive likelihood ratio for HBV mother-infant infection than HBV DNA and/or HBsAg at birth. CONCLUSIONS: Negativity for anti-HBs at 1 mo can be considered as a sensitive and early diagnostic indictor for HBV infection in the infants with positive HBV DNA and HBsAg at birth, especially for those infants with low levels of HBV DNA load and HBsAg titer.
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DNA Viral/sangue , Antígenos de Superfície da Hepatite B/sangue , Hepatite B/virologia , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Complicações Infecciosas na Gravidez/virologia , Adulto , Biomarcadores/sangue , Feminino , Hepatite B/tratamento farmacológico , Hepatite B/prevenção & controle , Anticorpos Anti-Hepatite B/sangue , Vacinas contra Hepatite B/imunologia , Vacinas contra Hepatite B/uso terapêutico , Humanos , Imunoglobulinas/uso terapêutico , Lactente , Recém-Nascido , Masculino , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Complicações Infecciosas na Gravidez/prevenção & controle , Estudos Prospectivos , Adulto JovemRESUMO
OBJECTIVE: To conduct a prospective randomized controlled trial of infants born to hepatitis B virus (HBV) surface antigen (HBsAg)-positive mothers in order to investigate the dynamic changes in the titer of anti-HBV surface protein (HBS) induced by treatment with combined immunoprophylaxis (200 IU hepatitis B immunoglobulin (HBIG) and 5 or 10 mug yeast recombinant hepatitis B vaccine), to compare the protective effect of 5 and 10 mug hepatitis B vaccine, and to provide an immunization strategy, monitoring mode and booster immunization schedule for the high-risk group. METHODS: Two-hundred-and-sixty-nine infants born to HBsAg positive mothers were given combined immunoprophylaxis at birth, and the venous blood samples (at birth, and 1, 7 and 12 months) were tested for HBV DNA load, and HBsAg and anti-HBS titers. RESULTS: The overall 1-year protective rate of combined immunoprophylaxis was 95.9%. There was no significant difference between the infectious rates of infants given the 5 mug or the 10 mug hepatitis B vaccine (x2 = 0.876, P = 0.377). The geometric mean titers (GMTs) of anti-HBS were 144.1 mIU/ml at 1-month old and 564.9 mIU/ml at the age of 7 months old (the highest point), but declined to 397.6 mIU/ml at the age of 12 months old. The rate of infants with anti-HBS titer less than 100 mIU/ml was 20.9%, and that of less than 10 mIU/ml was 7.4% at 7-month-old; the rate of infants with anti-HBS titer less than 100 mIU/ml increased to 30.2% and that of less than 10 mIU/ml increased to 15.9% at 12-month-old. At 7-month-old, the GMT of the 10 mug vaccine group was higher than that of the 5 mug vaccine group (675.3 mIU/ml vs. 25.0 mIU/ml, P = 0.001) and the rate of infants with anti-HBS titer less than 10 mIU/ml was significantly lower in the 10 mug vaccine group (2.3% vs. 12.6%, P = 0.002); at 12-month-old, the rate of infants with anti-HBS titer less than 100 mIU/ml was also significantly lower in the 10 mug group (20.6% vs. 40.2%, P = 0.001). CONCLUSION: Combined immunoprophylaxis is therapeutically efficacious for treating infants born to HBsAg positive mothers. Monitoring these infants' anti-HBs titer will help to identify non- or low-responders in a timely manner. The high-dose hepatitis B vaccine is preferable to the low-dose, and should be considered for use in immunization strategies for these infants.
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Anticorpos Anti-Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/sangue , Vacinas contra Hepatite B/uso terapêutico , Hepatite B/imunologia , Hepatite B/prevenção & controle , Feminino , Hepatite B/sangue , Anticorpos Anti-Hepatite B/sangue , Antígenos de Superfície da Hepatite B/imunologia , Humanos , Lactente , Mães , Estudos Prospectivos , Carga ViralRESUMO
Background: Engaging in social activities can help older persons with their depressed symptoms. Few studies, however, have looked into the connection between social interactions and depressed symptoms in Chinese older persons. The aim of this study was to investigate differences in older Chinese individuals' social activity involvement and depressive symptoms across urban and rural settings. Methods: A cross-sectional investigation using information from the 2018 China Health and Retirement Longitudinal Study (CHARLS), which was limited to older individuals aged 60 and over. Generalized linear models were constructed to assess the effects of participants' characteristics and specific social activities on CES-D scores. The association between specific social activities and depressed symptoms was investigated using multivariate logistic regression analysis. Results: In this study, it was discovered that older individuals had a prevalence of depressed symptoms of 36.2%, with rural older adults having a greater prevalence of depressive symptoms (39.7%) than urban older adults (30.9%). Our results showed that for urban respondents, providing help to others (not regularly. OR = 0.753, 95% CI: 0.579-0.980, P = 0.035), going to a sport (not regularly. OR = 0.685, 95% CI: 0.508-0.924, P = 0.013), and using the Internet (not regular. OR = 0.613, 95% CI: 0.477-0.789, P < 0.001; almost weekly. OR = 0.196, 95% CI: 0.060-0.645, P = 0.007) were all significantly and negatively associated with depressive symptoms, while for rural respondents, interacting with friends (not regularly. OR = 1.205, 95% CI: 1.028-01.412, P = 0.021) and using the Internet (not regularly. OR = 0.441, 95% CI: 0.278-0.698, P < 0.001) were significantly and negatively associated with depressive symptoms. Conclusions: According to our research, there is a cross-sectional relationship between participating in a specific social activity and depressed symptoms in Chinese older adults, and this relationship varies across urban and rural older adults. This suggests that taking part in specific social activities may be crucial for reducing depression symptoms in older persons, developing more focused interventions that might support healthy aging, and offering a guide for policymakers and activists working to improve the mental health of seniors.
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Depressão , Aposentadoria , Humanos , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Depressão/epidemiologia , Depressão/psicologia , Estudos Longitudinais , Aposentadoria/psicologia , Comportamento Social , China/epidemiologiaRESUMO
The increase in the concentration of CO2 in the atmosphere has attracted widespread attention. To explore the effect of elevated CO2 on lettuce growth and better understand the mechanism of elevated CO2 in lettuce cultivation, 3 kinds of lettuce with 4 real leaves were selected and planted in a solar greenhouse. One week later, CO2 was applied from 8:00 a.m. to 10:00 a.m. on sunny days for 30 days. The results showed that the growth potential of lettuce was enhanced under CO2 enrichment. The content of vitamin C and chlorophyll in the three lettuce varieties increased, and the content of nitrate nitrogen decreased. The light saturation point and net photosynthetic rate of leaves increased, and the light compensation point decreased. Transcriptome analysis showed that there were 217 differentially expressed genes (DEGs) shared by the three varieties, among which 166 were upregulated, 44 were downregulated, and 7 DEGs were inconsistent in the three materials. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that these DEGs involved mainly the ethylene signaling pathway, jasmonic acid signaling pathway, porphyrin and chlorophyll metabolism pathway, starch and sucrose metabolism pathway, etc. Forty-one DEGs in response to CO2 enrichment were screened out by Gene Ontology (GO) analysis, and the biological processes involved were consistent with KEGG analysis. which suggested that the growth and nutritional quality of lettuce could be improved by increasing the enzyme activity and gene expression levels of photosynthesis, hormone signaling and carbohydrate metabolism. The results laid a theoretical foundation for lettuce cultivation in solar greenhouses and the application of CO2 fertilization technology.
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Dióxido de Carbono , Lactuca , Dióxido de Carbono/análise , Transcriptoma , Clorofila/metabolismo , Perfilação da Expressão GênicaRESUMO
Pathological cardiac hypertrophy is an important risk factor for cardiovascular disease. However, drug therapies that can reverse the maladaptive process and restore heart function are limited. Ganoderma lucidum polysaccharides (GLPs) are one of the main active components of G. lucidum (Ganoderma lucidum), and they have various pharmacological effects. GLPs have been used as Chinese medicine prescriptions for clinical treatment. In this study, cardiac hypertrophy was induced by transverse aortic constriction (TAC) in mice. We found that GLPs ameliorate Ang II-induced cardiomyocyte hypertrophy in vitro and attenuate pressure overload-induced cardiac hypertrophy in vivo. Further research indicated that GLPs attenuated the mRNA levels of hypertrophic and fibrotic markers to inhibit cardiac hypertrophy through the PPARγ/PGC-1α pathway. Overall, these results indicate that GLPs inhibit cardiac hypertrophy through downregulating key genes for hypertrophy and fibrosis and attenuate pressure overload-induced pathological cardiac hypertrophy by activating PPARγ. This study provides important theoretical support for the potential of using GLPs to treat pathological myocardial hypertrophy and heart failure.
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BACKGROUND: Home oxygen therapy (HOT) is indicated upon discharge in some preterm infants with severe bronchopulmonary dysplasia (BPD). There is a lack of evidence-based consensus on the indication for HOT among these infants. Because wide variation in the institutional use of HOT exists, little is known about the role of regional social-economic level in the wide variation of HOT. METHODS: This was a secondary analysis of Chinese Neonatal Network (CHNN) data from January 1, 2019 to December 31, 2019. Infants at gestational ages < 32 weeks, with a birth weight < 1500 g, and with moderate or severe BPD who survived to discharge from tertiary hospitals located in 25 provinces were included in this study. Infants with major congenital anomalies and those who were discharged against medical advice were excluded. RESULTS: Of 1768 preterm infants with BPD, 474 infants (26.8%) were discharged to home with oxygen. The proportion of HOT use in participating member hospitals varied from 0 to 89%, with five of 52 hospitals' observing proportions of HOT use that were significantly greater than expected, with 14 hospitals with observing proportions significantly less than expected, and with 33 hospitals with appropriate proportions. We noted a negative correlation between different performance groups of HOT and median GDP per capita (P = 0.04). CONCLUSIONS: The use of HOT varied across China and was negatively correlated with the levels of provincial economic levels. A local HOT guideline is needed to address the wide variation in HOT use with respect to different regional economic levels in countries like China.
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Displasia Broncopulmonar , Recém-Nascido Prematuro , Lactente , Recém-Nascido , Humanos , Displasia Broncopulmonar/terapia , Displasia Broncopulmonar/complicações , Idade Gestacional , Oxigênio/uso terapêutico , China , Estudos de Coortes , Recém-Nascido de muito Baixo PesoRESUMO
BACKGROUND: Esophageal atresia (EA) is a life-threatening congenital malformation in newborns, and the traditional repair approaches pose technical challenges and are extremely invasive. Therefore, surgeons have been actively investigating new minimally invasive techniques to address this issue. Magnetic compression anastomosis has been reported in several studies for its potential in repairing EA. In this paper, the primary repair of EA with magnetic compression anastomosis under thoracoscopy was reported. CASE SUMMARY: A full-term male weighing 3500 g was diagnosed with EA gross type C. The magnetic devices used in this procedure consisted of two magnetic rings and several catheters. Tracheoesophageal fistula ligation and two purse strings were performed. The magnetic compression anastomosis was then completed thoracoscopically. After the primary repair, no additional operation was conducted. A patent anastomosis was observed on the 15th day postoperatively, and the magnets were removed on the 23rd day. No leakage existed when the transoral feeding started. CONCLUSION: Thoracoscopic magnetic compression anastomosis may be a promising minimally invasive approach for repairing EA.
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OBJECTIVE: To study the protocol of construction of a KCNQ2-c.812G>T mutant and it's eukaryotic expression vector, the c.812G>T (p.G271V) mutation which was detected in a Chinese pedigree of benign familial infantile convulsions, and to examine the expression of mutant protein in human embyonic kidney (HEK) 293 cells. METHODS: A KCNQ2 mutation c.812G>T was engineered on KCNQ2 cDNAs cloned into pcDNA3.0 by sequence overlap extension PCR and restriction enzymes. HEK293 cells were co-transfected with pRK5-GFP and KCNQ2 plasmid (the wild type or mutant) using lipofectamine and then subjected to confocal microscopy. The transfected cells were immunostained to visualize the intracellular expression of the mutant molecules. RESULTS: Direct sequence analysis revealed a G to T transition at position 812. The c.812G>T mutation was correctly combined to eukaryotic expressive vector pcDNA3.0 and expressed in HEK293 cells. Immunostaining of transfected cells showed the expression of both the wild type and mutant molecules on the plasma membrane, which suggested that the c.812G>T mutation at the pore forming region of KCNQ2 channel did not impair normal protein expression in HEK293 cells. CONCLUSIONS: Successful construction of mutant KCNQ2 eukaryotic expression vector and expression of KCNQ2 protein in HEK293 cells provide a basis for further study on the functional effects of convulsion-causing KCNQ2 mutations and for understanding the molecular pathogenesis of epilepsy.
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Epilepsia Neonatal Benigna/genética , Canal de Potássio KCNQ2/genética , Imunofluorescência , Vetores Genéticos , Células HEK293 , Humanos , Recém-Nascido , Canal de Potássio KCNQ2/análise , Canal de Potássio KCNQ2/fisiologia , Mutagênese Sítio-Dirigida , Reação em Cadeia da PolimeraseRESUMO
The CO2 saturation point can reach as high as 1819 µmol· mol-1 in carrot (Daucus carota L.). In recent years, carrot has been cultivated in out-of-season greenhouses, but the molecular mechanism of CO2 enrichment has been ignored, and this is a missed opportunity to gain a comprehensive understanding of this important process. In this study, it was found that CO2 enrichment increased the aboveground and belowground biomasses and greatly increased the carotenoid contents. Twenty genes related to carotenoids were discovered in 482 differentially expressed genes (DEGs) through RNA sequencing (RNA-Seq.). These genes were involved in either carotenoid biosynthesis or the composition of the photosystem membrane proteins, most of which were upregulated. We suspected that these genes were directly related to quality improvement and increases in biomass under CO2 enrichment in carrot. As such, ß-carotene hydroxylase activity in carotenoid metabolism and the expression levels of coded genes were determined and analysed, and the results were consistent with the observed change in carotenoid content. These results illustrate the molecular mechanism by which the increase in carotenoid content after CO2 enrichment leads to the improvement of quality and biological yield. Our findings have important theoretical and practical significance.
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Dióxido de Carbono/metabolismo , Carotenoides/metabolismo , Daucus carota , Regulação da Expressão Gênica de Plantas , Genes de Plantas , RNA-Seq , Daucus carota/genética , Daucus carota/metabolismoRESUMO
AIM OF STUDY: The conclusions on the association between the rs2736100 polymorphisms of telomerase reverse transcriptase (TERT) gene polymorphism and digestive cancers risk are still debated. This meta-analysis was conducted to update the association between the TERT rs2736100 polymorphisms and the risk of digestive cancers. MATERIALS AND METHODS: The association investigations were identified from PubMed and Cochrane Library, and eligible studies were included and synthesized using the meta-analysis method. RESULTS: Eight case-control studies were included in this meta-analysis for associating TERT rs2736100 gene polymorphism and digestive cancer susceptibility. Pooled odds ratio with 95% confidence interval was calculated using a fixed or random-effects model. Overall, no evidence has shown that the TERT rs2736100 polymorphism was associated with the susceptibility to digestive cancers. Besides, stratified analysis with ethnicity also indicated no significant association between TRET rs2736100 and the risk of digestive cancers under all genetic models in both Asian and Caucasian populations were observed. CONCLUSION: According to the meta-analysis, TERT rs2736100 polymorphism might be unrelated to digestive cancer susceptibility. Evidence with adequate sample size is still needed.
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Biomarcadores Tumorais/genética , Neoplasias do Sistema Digestório/patologia , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Telomerase/genética , Estudos de Casos e Controles , Neoplasias do Sistema Digestório/genética , Humanos , Prognóstico , Fatores de RiscoRESUMO
Esophageal squamous cell carcinoma (ESCC) is a dominant histological subtype of esophageal cancer with notably high incidence and mortality rates. Pemetrexed is a clinical antifolate therapeutic agent with anticancer properties. The present study aimed to understand whether pemetrexed is able to exert anticancer effects on ESCC cells, and to determine the underlying molecular mechanism. ESCC cells were treated with pemetrexed and cell survival was assessed with MTT assays. The cell cycle and apoptosis were evaluated using flow cytometry analysis, and proteins were detected using western blotting. It was demonstrated that pemetrexed inhibited cell survival and induced G0/G1 cell cycle arrest and apoptosis in human ESCC cells. Furthermore, the results demonstrated that the phorbol-12-myristate-13-acetate-induced protein 1/induced myeloid leukemia cell differentiation protein Mcl-1 axis is involved in intrinsic apoptosis induced by pemetrexed. The protein expression of endoplasmic reticulum stress markers inositol-requiring enzyme 1α, binding immunoglobulin protein and CCAAT-enhancer-binding protein homologous protein were upregulated following treatment with pemetrexed. These results suggest that pemetrexed may induce an endoplasmic reticulum stress response while activating intrinsic apoptosis. The present study provided important mechanistic insights into potential cancer treatments involving pemetrexed and enhanced the understanding of human ESCC.
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OBJECTIVE: To obtain the Rnf141 polyclonal antibody and to study its function. METHODS: Rnf141 cDNA was obtained by PCR amplification and inserted into the expression vector pGEX-5X-3, which encoding the GST protein to generate a recombinant plasmid. The recombinant was transformed into E. coli BL21 (DE3). After inducing with 1 mmol/L IPTG at 25 degrees C, the GST-Rnf141 fusion protein was expressed at a high level as a soluble form. Purified fusion protein with Glutathione Sephorase 4B chromatography was applied to immune rabbits to prepare the polyclonal antibody. Western blot and immunohistochemistry were applied to confirm the specificity of the resulting antibody. RESULTS: pGEX-Rnf141 recombinant plasmid was constructed successfully and the resulting. GST-Rnf141 fusion protein could be expressed in E. coli BL21(DE3) at a relatively high level, standing for 46% of total bacteria protein. The titer of the antiserum was 1:128000 and the polyclonal antibody could recognize GST-Rnf141 fusion protein and Rnf141 protein in different tissues of mouse. The high expression of Rnf141 protein was observed in spleen and brain of mouse. CONCLUSION: Rnf141 polyclonal antibody was prepared successfully and this will provide material for further studies of Rnf141 expression and function.
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Anticorpos Monoclonais/biossíntese , Proteínas de Ligação a DNA/genética , Proteínas Recombinantes de Fusão/genética , Fatores de Transcrição/genética , Animais , Proteínas de Ligação a DNA/biossíntese , Escherichia coli/genética , Escherichia coli/metabolismo , Células Eucarióticas/metabolismo , Vetores Genéticos/genética , Camundongos , Proteínas Recombinantes de Fusão/biossíntese , Fatores de Transcrição/biossínteseRESUMO
An extracellular xylanase was purified to homogeneity from a culture of Streptomyces chartreusis L1105 by a 2-step method of ammonium sulfate precipitation and carboxymethyl sepharose fast-flow chromatography (CMSFF). The xylanase was purified by 6.86-fold, with a recovery yield of 31.96%. The purified xylanase appeared as a single protein band on SDS-PAGE with a molecular mass of about 34.2 kDa. The optimum temperature and pH of the purified xylanase activity were 70 °C and 7.2 respectively. The xylanase was more stable under alkaline conditions and retained more than 80% activity after 30 min incubation at pH 6 to 10. It also showed specific activity towards different xylans. Hydrolysis of oat-spelt and corn-cob xylans by the xylanase yielded xylobiose and xylotriose as principle products without the formation of xylose. These properties indicate that the purified xylanase may potentially be useful in biotechnological applications, such as xylooligosaccharide preparation. This is the first report about the purification and characterization of a xylanase from S. chartreusis.
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Glucuronatos/biossíntese , Oligossacarídeos/biossíntese , Streptomyces/enzimologia , Xilosidases/isolamento & purificação , Xilosidases/metabolismo , Ácido Edético/química , Eletroforese em Gel de Poliacrilamida , Concentração de Íons de Hidrogênio , Hidrólise , Peso Molecular , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Streptomyces/genética , Especificidade por Substrato , Temperatura , Xilanos/metabolismoRESUMO
OBJECTIVE: To study the protocol of construction of a KCNQ2-c.812G>T mutant and its eukaryotic expression vector, the c.812G>T (p.G271V) mutation, which was detected in a Chinese pedigree of benign familial infantile convulsions (BFIC), and to examine the expression of mutant protein in human embyonic kidney (HEK) 293 cells. METHODS: A KCNQ2 mutation c.812G>T was engineered on KCNQ2 cDNAs cloned into pcDNA3.0 by sequence overlap extension PCR and restriction enzymes. HEK293 cells were co-transfected with pRK5-GFP and KCNQ2 plasmid (the wild type or mutant) using lipofectamine and then subjected to confocal microscopy. The transfected cells were immunostained to visualize the intracellular expression of the mutant molecules. RESULTS: Direct sequence analysis revealed a G to T transition at position 812. The c.812G>T mutation was correctly combined to eukaryotic expressive vector pcDNA3.0 and expressed in HEK293 cells. Immunostaining of transfected cells showed the expression of both the wild type and mutant molecules on the plasma membrane, which suggested that the c.812G>T mutation at the pore forming region of KCNQ2 channel did not impair normal protein expression in HEK293 cells. CONCLUSIONS: Successful construction of mutant KCNQ2 eukaryotic expression vector and expression of KCNQ2 protein in HEK293 cells provide a basis for further study on the functional effects of convulsion-causing KCNQ2 mutations and for understanding the molecular pathogenesis of epilepsy.
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OBJECTIVE: To detect possible relationship between genetic defect within the gene encoding member A3 of the ATP Binding Cassette family (ABCA3) and neonatal respiratory distress syndrome (NRDS), thus to understand the genetic mechanisms of NRDS in Han ethnic group. METHOD: The clinical data of 11 cases with NRDS hospitalized in neonatal intensive care unit was investigated. Blood samples were collected from 11 cases with NRDS and 97 unassociated normal individuals. Polymerase chain reaction (PCR) and DNA direct sequencing were performed to screen all exons and their flanking introns of ABCA3 gene for mutation analysis in 11 cases with NRDS. If a new missense variation was identified, single strand conformation polymorphism analysis was performed in 97 healthy controls. Lung tissue sample from a case who died 12 hours after birth was examined with light microscopy and electron microscopy. RESULT: Three missense genetic variants in exons, which include c. 2169 G > A (p.M723I), c. 1010 T > G (p.V337G), c. 4972 A > G (p.S1658G), one splice junction site variation (Exon 30 + 2 T/G), several unreported polymorphism sites [213 C > T(p.F71F), exon 21 + 34C/T] and reported polymorphism site (p.F353F) were identified on ABCA3 gene coding region in 11 case. The homozygous variation (c.2169G > A), which was in exon 17 and causes an M723I amino acid change, was found in the case who died 13 hours after birth, but not detected in 97 controls, indicating that this variation is indeed a mutation and not a polymorphism. In the case carrying c.2169G > A, ultrastructural examination of the alveolar type II cells with electron microscopy demonstrated abnormally small and dense lamellar body with eccentrically distributed electron dense substance. CONCLUSION: Genetic variants within ABCA3 may be the genetic cause of or a contributor to some unexplained refractory NRDS. Identification of ABCA3 genetic variant in NRDS infants is important to establish appropriate management and evaluation of treatment options, as well as to offer genetic counseling and prenatal diagnosis.
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Transportadores de Cassetes de Ligação de ATP/genética , Síndrome do Desconforto Respiratório do Recém-Nascido/genética , Análise Mutacional de DNA , Éxons , Humanos , Recém-Nascido , Polimorfismo Genético , Síndrome do Desconforto Respiratório do Recém-Nascido/etiologiaRESUMO
The testis-specific serine/threonine kinase (TSSK) family is a specific kinase group with exclusive or dominant expression in testis and involvement in spermatogenesis and male infertility. TSSK4 is a newly identified member of the TSSK family. In order to investigate the possible relationships between variations, including mutations and polymorphisms of the TSSK4 gene and impaired spermatogenesis in humans, mutation screening of this gene in 372 patients with azoospermia or severe oligospermia and 220 controls was performed. In total, 4 novel single nucleotide changes including c.679G>A, c.987+108G>A, c.-155C>G and c.765C>A were discovered. The latter 2 variations were found only in patients, not in controls. Bioinformatics analysis suggested that allele A of c.765C>A could decrease the activity of pre-mRNA splicing of TSSK4. The frequency of allele A of c.679G>A was significantly higher in controls than in patients. On the contrary, allele A of c.987+108G>A was remarkably increased in patients compared with controls. Our investigation of TSSK4, a potentially important testicular gene, in Chinese infertile and control men identified the association of some single nucleotide polymorphisms in this gene with male infertility.
Assuntos
Predisposição Genética para Doença , Testes Genéticos , Infertilidade Masculina/genética , Proteínas Serina-Treonina Quinases/genética , Espermatogênese/fisiologia , Adulto , Povo Asiático , Sequência de Bases , Cromatografia Líquida de Alta Pressão , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Polimorfismo de Nucleotídeo ÚnicoRESUMO
Znf230, the mouse homologue of the human spermatogenesis-related gene, ZNF230, has been cloned by rapid amplification of cDNA ends (RACE). This gene is expressed predominantly in testis, but its expression in different testicular cells and spermatogenic stages has not been previously analyzed in detail. In the present study, the cellular localization of the Znf230 protein in mouse testis and epididymal spermatozoa was determined by RT-PCR, immunoblotting, immunohistochemistry and immunofluorescence. It is primarily expressed in the nuclei of spermatogonia and subsequently in the acrosome system and the entire tail of developing spermatids and spermatozoa. The results indicate that Znf230 may play an important role in mouse spermatogenesis, including spermatogenic cell proliferation and sperm maturation, as well as motility and fertilization.