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1.
Nan Fang Yi Ke Da Xue Xue Bao ; 42(1): 137-142, 2022 Jan 20.
Artigo em Chinês | MEDLINE | ID: mdl-35249881

RESUMO

OBJECTIVE: To explore the differences in the factors associated with endometriosis between Chinese and British patients. METHODS: This case-control study was conducted in 387 patients with endometriosis and 199 non-endometriosis patients admitted to John Radcliffe Hospital (Oxford, UK) and in 101 patients with endometriosis and 50 non-endometriosis patients admitted in the First Affiliated Hospital of Guangzhou University of Chinese Medicine. The clinical data including height, weight, body mass index, marital status, employment, menstruation, fertility, and operation reasons were collected via a standardized WERF EPHect questionnaire. RESULTS: Multivariate logistic regression analysis indicated that body mass index, surgery for dysmenorrhea, history of pregnancy, counts of previous surgeries for endometriosis and status of employment were all significantly associated with endometriosis in the UK (P < 0.05), while a history of dysmenorrhea was significantly correlated with endometriosis in Chinese patients (P < 0.05). CONCLUSION: Dysmenorrhea may be the most important common factor associated with endometriosis in China and the UK, but the other factors contributing to endometriosis may differ between these two countries.


Assuntos
Endometriose , Estudos de Casos e Controles , Dismenorreia/complicações , Endometriose/complicações , Feminino , Humanos , Menstruação , Gravidez , Reino Unido
2.
Eur Rev Med Pharmacol Sci ; 25(5): 2154, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33755943

RESUMO

We detected some serious inaccuracies and mistakes. Therefore, the article, "Circular RNA circ-NT5C2 acts as a potential novel biomarker for prognosis of osteosarcoma, by W.-B. Nie, L.-M. Zhao, R. Guo, M.-X. Wang, F.-G. Ye, published in Eur Rev Med Pharmacol Sci 2018; 22 (19): 6239-6244-DOI: 10.26355/eurrev_201810_16030-PMID: 30338784" has been withdrawn. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/16030.

3.
Eur Rev Med Pharmacol Sci ; 22(19): 6239-6244, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30338784

RESUMO

OBJECTIVE: Recent evidence suggests that circular RNAs (circRNAs) play important roles in multiple diseases, including cancer. Circ-NT5C2 was reported to be up-regulated in osteosarcoma. However, the clinical significance of circ-NT5C2 remains largely unclear. The aim of the current study was to investigate the value of circ-NT5C2 for the prognosis of patients with osteosarcoma. PATIENTS AND METHODS: the expression of circ-NT5C2 in osteosarcoma tissues and corresponding normal tissues were explored by quantitative real-time polymerase chain reaction (qRT-PCR) experiments. The association of circ-NT5C2 expression with clinicopathological factors or the prognosis of osteosarcoma patients was also analyzed. Kaplan-Meier survival analysis was performed to analyze the association of circ-NT5C2 expression with overall survival (OS) and disease-free survival (DFS) of patients. Univariate and multivariate Cox-regression analyses were used to identify risk factors for poor prognosis. RESULTS: Our data showed a significant increase of circ-NT5C2 expression in osteosarcoma tissues compared with adjacent normal bone tissues (p < 0.01). In addition, we found that the level of circ-NT5C2 in osteosarcoma was strongly correlated with clinical stage (p = 0.006) and distant metastasis (p = 0.001). Importantly, patients with high expression of circ-NT5C2 had a shorter OS (p = 0.006) and DFS (p = 0.001) than those with low expression of circ-NT5C2. Finally, Cox regression analyses showed that high circ-NT5C2 expression might be an independent prognostic parameter to predict poor prognosis. CONCLUSIONS: Our findings indicated that circ-NT5C2 is significantly up-regulated in osteosarcoma tissues. Circ-NT5C2 may represent a new marker of prognosis in osteosarcoma.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Ósseas/metabolismo , Osteossarcoma/metabolismo , RNA Circular/metabolismo , Adulto , Biomarcadores Tumorais/genética , Neoplasias Ósseas/genética , Neoplasias Ósseas/mortalidade , Neoplasias Ósseas/patologia , Progressão da Doença , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Estadiamento de Neoplasias , Osteossarcoma/genética , Osteossarcoma/mortalidade , Osteossarcoma/patologia , RNA Circular/genética , Fatores de Risco , Transdução de Sinais , Adulto Jovem
4.
Transplant Proc ; 50(8): 2465-2468, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30316380

RESUMO

OBJECTIVES: This study aimed to identify the potential risk factors of acute rejection after deceased donor kidney transplantation in China. METHODS: Adult kidney transplantations from deceased donors in our center from February 2004 to December 2015 were enrolled for retrospective analysis. All deceased donations complied with China's Organ Donation Program. No organs from executed prisoners were used. The incidence of clinical and biopsy-proved acute rejection was assessed with the Kaplan-Meier method, and the Cox proportional hazard model was used for multivariate analysis. RESULTS: One-year, 2-year, 3-year and 5-year incidences of acute rejection were 12.4%, 14.2%, 14.8%, and 17.1%, respectively. Multivariate analysis demonstrated that longer pre-transplant dialysis duration (hazard ratio [HR] 1.009 per month; 95% confidence interval, 1.003-1.015; P = .003), positive pre-transplant panel reactive antibody (PRA) (positive vs negative HR 3.266; 1.570-6.793; P = .023), and increasing HLA mismatches (≥4 vs < 4 HR 2.136; 1.022-4.465; P = .044) increased the risk of acute rejection, while tacrolimus decreased acute rejection risk compared to cyclosporine (HR 0.317; 0.111-0.906; P = .032). CONCLUSION: Longer pre-transplant dialysis duration, HLA mismatch, and positive pre-transplant PRA increase the risk of acute rejection, while tacrolimus helps prevent acute rejection compared to cyclosporine in deceased donor kidney transplantation.


Assuntos
Rejeição de Enxerto/epidemiologia , Transplante de Rim/métodos , Doadores de Tecidos/provisão & distribuição , Adulto , China , Ciclosporina/uso terapêutico , Morte , Feminino , Rejeição de Enxerto/imunologia , Sobrevivência de Enxerto , Humanos , Imunossupressores/uso terapêutico , Incidência , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Tacrolimo/uso terapêutico
5.
Neoplasma ; 64(4): 554-562, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28485161

RESUMO

Non-small cell lung cancer (NSCLC) is one of the most deadly human cancers. MicroRNA-300 acts as both tumor promoter and suppressor in different types of cancer. Here, we try to identify the function of microRNA-300 in human NSCLC. We compared MicroRNA-300 levels between tumor tissues versus paired adjacent non-tumor lung tissues from NSCLC patients, and in NSCLC versus normal lung cell lines. Effects of microRNA-300 on cell proliferation, invasion and migration were examined in vitro, and on tumor growth in vivo using a xenograft mouse model. Potential mRNA targets of microRNA-300 were predicted and underlying mechanism was explored. MicroRNA-300 expression was lower in both NSCLC tissues and cell lines. Overexpression of microRNA-300 inhibited proliferation, invasion and migration of NSCLC cells in vitro, and tumor growth in vivo. MicroRNA-300 could directly bind to the 3'-UTR of hypoxia inducible factor-3 alpha (HIF3α) mRNA, and inhibit both its mRNA and protein expressions. Restoring HIF3α expression could rescue the inhibitory effects of microRNA-300 on tumorigenesis of NSCLC both in vitro and in vivo. MicroRNA-300 is a tumor suppressor microRNA in NSCLC by downregulating HIF3α expression. Both microRNA-300 and HIF3α may serve as potential therapeutic targets in NSCLC treatment.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , MicroRNAs/genética , Animais , Proteínas Reguladoras de Apoptose , Carcinogênese , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/patologia , Camundongos , Proteínas Repressoras , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Sci Rep ; 6: 18998, 2016 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-26753788

RESUMO

Severe air pollution episodes have been frequent in China during the recent years. While high emissions are the primary reason for increasing pollutant concentrations, the ultimate cause for the most severe pollution episodes has remained unclear. Here we show that a high concentration of particulate matter (PM) will enhance the stability of an urban boundary layer, which in turn decreases the boundary layer height and consequently cause further increases in PM concentrations. We estimate the strength of this positive feedback mechanism by combining a new theoretical framework with ambient observations. We show that the feedback remains moderate at fine PM concentrations lower than about 200 µg m(-3), but that it becomes increasingly effective at higher PM loadings resulting from the combined effect of high surface PM emissions and massive secondary PM production within the boundary layer. Our analysis explains why air pollution episodes are particularly serious and severe in megacities and during the days when synoptic weather conditions stay constant.


Assuntos
Aerossóis/análise , Poluição do Ar/análise , Retroalimentação , China , Material Particulado/análise , Fuligem/análise , Luz Solar , Fatores de Tempo
7.
Cell Mol Biol (Noisy-le-grand) ; 61(3): 96-101, 2015 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-26255138

RESUMO

It is known, for a long time, that angiotensin II (Ang II) could contribute to atherogenesis (AS) and plaque vulnerability, however the underlying mechanisms are poorly understood. Dendritic cells (DCs) are critical for the development of both inflammation and atherogenesis. In the present study, we tried to investigate the influence of AngII on the expression of connexin43 (Cx43) in DCs, as well as the effect of AngII on AS. After mouse bone marrow—derived dendritic cells (BMDCs) were treated by Ang II with or without Valsartan, the expression of Cx43 was quantified by Western Blots. The expression of Cx43 and CD40 (one marker of DCs) of DCs derived from AS plaques of ApoE—/— mice was detected by immunohistochemistry double staining. The morphology of atherosclerotic plaque was indicated by immunohistochemistry staining of smooth muscle cells. The expression of Cx43 (P < 0.05) was increased significantly in mouse BMDCs after treatment with AngII. In atherosclerotic plaques from ApoE—/— mice expressing high levels of endogenous AngII, upregulation of Cx43 (P < 0.01) and CD40 (P < 0.01) was observed. The upregulation and pro—atherogenesis effect of Cx43 could be blocked by the AngII type 1 receptor blocker Valsartan, both in vitro and in vivo. AngII may promote atherosclerosis and plaque vulnerability by increasing the expression of Cx43 in DCs and inducing the maturation of DCs through the angiotensin II type 1 receptor.


Assuntos
Angiotensina II/farmacologia , Aterosclerose/etiologia , Conexina 43/metabolismo , Células Dendríticas/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Animais , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Antígenos CD40/metabolismo , Células Cultivadas , Conexina 43/genética , Células Dendríticas/citologia , Células Dendríticas/metabolismo , Imuno-Histoquímica , Lipopolissacarídeos/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , Valsartana/farmacologia
8.
Eur J Vasc Endovasc Surg ; 50(4): 450-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26100449

RESUMO

OBJECTIVE: This study evaluates the safety and efficacy of pre-placement of a distal bare stent as an adjunct to thoracic endovascular aortic repair (TEVAR) in the setting of complicated acute Stanford type B aortic dissection (cTBAD). METHODS: The records of all patients diagnosed with cTBAD at the institution between 2010 and 2013 were reviewed. Indications for the pre-placement of a distal bare stent included symptomatic malperfusion and/or radiological evidence of true lumen collapse. Computed tomography angiography was performed post-operatively to assess aortic remodeling. RESULTS: 148 patients were treated for cTBAD: 113 patients (76.4%) were treated with standard TEVAR and 35 (23.6%) were treated by combined proximal TEVAR with pre-placement of an adjunctive distal bare stent. Primary technical success was 95.9%. The 30 day mortality rate was 4.1% and was not different between groups. The 30 day morbidity included transient renal failure (10.1%), endoleak (7.4%), and paraplegia (2.7%), and was not different between groups. The mean follow up was 10 months (range 2-12 months). No late stent complications were observed; patients with an adjunctive bare stent had less distal re-dissection (0% vs. 15%; p = .01) and fewer endovascular re-interventions (5.7% vs. 20.4%; p = .04). At 1 year, patients treated with TEVAR and an adjunctive distal bare stent had increased true lumen volume (166 vs. 110 mL; p = .022), decreased false lumen volume (60 vs. 90 mL; p = .043), and increased complete false lumen thrombosis in the thoracic (76.5% vs. 29.5%; p < .001) and abdominal (20.6% vs. 3.8%; p = .002) segments. CONCLUSIONS: Combined pre-placement of a distal bare stent as an adjunct to proximal TEVAR to treat cTBAD restricts oversizing of the distal stent graft, reducing the potential for distal true lumen collapse and visceral malperfusion, and improving remodeling of the dissected thoracic aorta. Long-term follow up and prospective studies are needed to assess the overall effectiveness of this treatment strategy.


Assuntos
Aorta Torácica/cirurgia , Aneurisma da Aorta Torácica/cirurgia , Dissecção Aórtica/cirurgia , Implante de Prótese Vascular , Prótese Vascular , Procedimentos Endovasculares , Stents , Remodelação Vascular , Doença Aguda , Adulto , Dissecção Aórtica/diagnóstico , Dissecção Aórtica/mortalidade , Dissecção Aórtica/fisiopatologia , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/fisiopatologia , Aneurisma da Aorta Torácica/diagnóstico , Aneurisma da Aorta Torácica/mortalidade , Aneurisma da Aorta Torácica/fisiopatologia , Aortografia/métodos , Implante de Prótese Vascular/instrumentação , Implante de Prótese Vascular/métodos , Implante de Prótese Vascular/mortalidade , China , Procedimentos Endovasculares/instrumentação , Procedimentos Endovasculares/métodos , Procedimentos Endovasculares/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/terapia , Desenho de Prótese , Recidiva , Estudos Retrospectivos , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento
9.
ScientificWorldJournal ; 2014: 185608, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25162042

RESUMO

With an increase in mining depth and production, the intensity and frequency of outburst of coal and gas have a tendency to increase. Estimating the intensity of outbursts of coal and gas plays an important role because of its relation with the risk value. In this paper, we described the semiquantitative relations between major parameters and intensity of outburst based on physical experiments. The results showed increment of geostress simulated by horizontal load (from 1.4, 2.4, 3.2, to 3.4 MPa) or vertical load (from 2, 3, 3.6, to 4 MPa) improved the relative intensity rate (3.763-7.403% and 1.273-7.99%); the increment of porosity (from 1.57, 2.51, 3, to 3.6%) improved the relative intensity rate from 3.8 to 13.8%; the increment of gas pressure (from 0, 0.5, 0.65, 0.72, 1, to 1.5 Mpa) induced the relative intensity rate to decrease from 38.22 to 0%; the increment of water content (from 0, 2, 4, to 8%) caused the relative intensity rate to drop from 5.425 to 0.5%. Furthermore, sensitivity and range analysis evaluates coupled factors affecting the relative intensity. In addition, the distinction with initiation of outburst of coal and gas affected by these parameters is discussed by the relative threshold of gas content rate.


Assuntos
Minas de Carvão , Mineração , Modelos Teóricos , Gás Natural , Geologia/instrumentação , Geologia/métodos , Risco
10.
J Investig Allergol Clin Immunol ; 24(6): 406-17, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25668892

RESUMO

BACKGROUND: Several studies have examined associations between TNF-α polymorphisms and asthma risk, but the results have been conflicting. METHODS: A search was performed of the PubMed, EMBASE, and Wanfang databases. Data were extracted and pooled ORs with 95% CIs were calculated. RESULTS: Fifty-four studies were included. A significant association between the TNFA-308A/G polymorphism and asthma susceptibility was observed for AA + AG vs GG (OR, 1.39; 95% CI, 1.23-1.58; P < .001). This polymorphism was also significantly associated with asthma risk in whites (OR, 1.47; 95% CI, 1.25-1.73; P < .001), atopic asthma risk (OR, 1.38; 95% CI, 1.16-1.65; P < .001), pediatric asthma risk (OR, 1.48; 95% CI, 1.23-1.79; P < .001), and adult asthma risk (OR, 1.35; 95% CI, 1.21-1.52; P < .001).There was also a significant association between the TNFA -857C/T polymorphism and asthma risk in the recessive model (OR, 1.25; 95% CI, 1.10-1.43; P < .001). In the subgroup analyses, asthma risk was significantly increased in Asians (OR, 1.23; 95% CI, 1.07-1.41; P = .004) and atopic individuals (OR, 1.33; 95% CI, 1.13-1.57; P < .001). No significant association was found for the TNFA-238A/G polymorphism. There were insufficient data to evaluate the associations between TNFA -1031T/C and -863C/A polymorphisms and asthma risk. CONCLUSIONS: This meta-analysis suggests that TNFA -308A/G and -857C/T polymorphisms are risk factors for asthma.


Assuntos
Asma/genética , Predisposição Genética para Doença , Polimorfismo Genético , Fator de Necrose Tumoral alfa/genética , Asma/etiologia , Genótipo , Humanos , Risco
11.
Br Poult Sci ; 53(5): 608-15, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23281754

RESUMO

1. The aim of the study was to determine if H(2)S is involved in the development of hypoxia-induced pulmonary hypertension in broilers, a condition frequently observed in a variety of cardiac and pulmonary diseases. 2. Two-week-old broilers were reared under normoxic conditions or exposed to normobaric hypoxia (6 h/day) with tissue levels of H(2)S adjusted by administering sodium hydrosulfide (NaHS, 10 µmol/kg body weight/day). Mean pulmonary arterial pressure, right ventricular mass, plasma and tissue H(2)S levels, the expression of cystathionine-ß-synthase (CSE) and vascular remodeling were determined at 35 d of age. 3. Exposure to hypoxia-induced pulmonary arterial hypertension was characterized by elevated pulmonary pressure, right ventricular hypertrophy and vascular remodeling. This was accompanied by decreased expression of CSE and decreased concentrations of plasma and tissue H(2)S. 4. Hypoxia-induced pulmonary hypertension was significantly reduced by administration of NaHS but this protective effect was largely abolished by D, L-propargylglycerine, an inhibitor of CSE. 5. The results indicate that H(2)S is involved in the development of hypoxia-induced pulmonary hypertension. Supplementing NaHS or H(2)S could be a strategy for reducing hypoxia-induced hypertension in broilers.


Assuntos
Cistationina beta-Sintase/metabolismo , Glicerol/farmacologia , Sulfeto de Hidrogênio/metabolismo , Hipertensão Pulmonar/veterinária , Hipertrofia Ventricular Direita/veterinária , Doenças das Aves Domésticas/tratamento farmacológico , Sulfetos/uso terapêutico , Animais , Ascite/tratamento farmacológico , Ascite/etiologia , Western Blotting/veterinária , Galinhas , Cistationina gama-Liase/metabolismo , Hipertensão Pulmonar Primária Familiar , Glicerol/análogos & derivados , Sulfeto de Hidrogênio/sangue , Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/metabolismo , Hipertrofia Ventricular Direita/tratamento farmacológico , Hipertrofia Ventricular Direita/etiologia , Hipertrofia Ventricular Direita/metabolismo , Hipóxia , Masculino , Doenças das Aves Domésticas/etiologia , Doenças das Aves Domésticas/metabolismo , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Espectrofotometria/veterinária , Sulfetos/metabolismo
12.
Vaccine ; 26(11): 1471-81, 2008 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-18289743

RESUMO

An orally delivered foot-and-mouth disease (FMD) vaccine has not previously been reported. By using a T4 bacteriophage nanoparticle surface gene-protein display system (T4-S-GPDS), we created a foot-and-mouth disease virus (FMDV) entire capsid protein vaccine candidate. On the T4 phage surface SOC site, a full length FMDV capsid precursor polyprotein (P1, 755 aa) and proteinase 3C (213 aa) derived from an infected pig of serotype O strain GD-10 (1999), were separately displayed on different T4 phage particle surfaces through inserting their coding region DNAs into the T4 phage genome, yielding phage strains T4-P1 and T4-3C. We also constructed a series of FMDV sub-full length capsid structural protein (subunit) containing T4 phage recombinant vaccines. Both sucking and young BALB/c mice were used as two kinds of FMDV vaccine potency evaluation models. Many groups of both model mice were vaccinated orally or by subcutaneous injection with varying FMDV-T4 phage recombinant vaccines, with and without addition of adjuvant, then challenged with a lethal dose of cattle source virulent FMDV. In the case of immunization with a mixture of phage T4-P1 and phage T4-3C particles without any adjuvant added, all mice were 100% protected following either oral or injection immunization, whereas 100% of the control, non-immunized mice and mice immunized with only T4 phage vector Z1/Zh(-) or wild-type T4(+)D phage died; in contrast, with FMDV subunit vaccine, less than 75% protection followed the same potency challenge in both mice model groups. In addition, two pigs immunized with a phage T4-P1 and phage T4-3C mix were protected upon housing together with infected pigs. This study represents a clear example of how FMD and other pathogenic disease vaccines can be prepared by a simple and efficient bacteriophage route.


Assuntos
Bacteriófago T4/imunologia , Capsídeo/imunologia , Vírus da Febre Aftosa/imunologia , Febre Aftosa/prevenção & controle , Vacinas Virais/imunologia , Animais , Animais Recém-Nascidos , DNA Viral/biossíntese , DNA Viral/genética , DNA Viral/imunologia , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Escherichia coli/ultraestrutura , Escherichia coli/virologia , Febre Aftosa/imunologia , Febre Aftosa/virologia , Vírus da Febre Aftosa/genética , Vírus da Febre Aftosa/patogenicidade , Injeções Subcutâneas , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica , Biblioteca de Peptídeos , Regiões Promotoras Genéticas/genética , Engenharia de Proteínas , Sorotipagem , Suínos , Vacinas Sintéticas/uso terapêutico
13.
Lett Appl Microbiol ; 40(5): 378-84, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15836743

RESUMO

AIMS: To study the effect of low pH stress on glutathione (GSH) synthesis and excretion capability of GSH fermentation production in Candida utilis. METHODS AND RESULTS: When C. utilis WSH 02-08 was cultivated in a glucose-ammonium sulfate medium without pH control, GSH leakage occurred when the pH of the medium decreased to 1.5. However, analysis of the cell viability indicated that the cells were not lysed. To further study the effect of low pH stress on GSH production, pH-controlled batch cultures were conducted, where the pH was switched from 5.5 to 1.2 at 24 h and maintained at 1.2 for 6 h. Nearly all intracellular GSH was leaked into the medium and the cell viability decreased dramatically, conceiving a long-term exposure of strain WSH 02-08 at low pH environment led to a complete cell lysis. A critical point (treated at pH 1.2 for 3 h) was experimentally determined, where most cells were alive but suffering a low pH stress. Low pH-stressed C. utilis cells displayed an increased intracellular GSH synthesis and export capability, which protected the cells against short-term low pH treatment. CONCLUSIONS: Using this knowledge, a low pH-stress strategy was developed and applied in fed-batch production of GSH and 197.3 mg l-1 of GSH was secreted into the medium. The GSH-specific production yield could be increased from 2.11 to 2.67% (w/w), and the total GSH concentration could reach 737.1 mg l-1 and increased by 24.9%. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report of GSH secretion of C. utilis at low pH. This study demonstrated the importance of the physiology-based fermentation strategy in the production of useful metabolites.


Assuntos
Candida/metabolismo , Glutationa/biossíntese , Candida/crescimento & desenvolvimento , Meios de Cultura , Fermentação , Glucose , Concentração de Íons de Hidrogênio
14.
Br J Pharmacol ; 129(5): 927-36, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10696092

RESUMO

Extracellular ATP can function as a glial trophic factor as well as a neuronal transmitter. In astrocytes, mitogenic signalling by ATP is mediated by metabotropic P(2Y) receptors that are linked to the extracellular signal regulated protein kinase (Erk) cascade, but the types of P(2Y) receptors expressed in astrocytes have not been defined and it is not known whether all P(2Y) receptor subtypes are coupled to Erk by identical or distinct signalling pathways. We found that the P(2Y) receptor agonists ATP, ADP, UTP and 2-methylthioATP (2MeSATP) activated Erk and its upstream activator MAP/Erk kinase (Mek). cRaf-1, the first kinase in the Erk cascade, was activated by 2MeSATP, ADP and UTP but, surprisingly, cRaf-1 was not stimulated by ATP. Furthermore, ATP did not activate B-Raf, the major isoform of Raf in the brain, nor other Mek activators such as Mek kinase 1 (MekK1) and MekK2/3. Reverse transcriptase-polymerase chain reaction (RT - PCR) studies using primer pairs for cloned rat P(2Y) receptors revealed that rat cortical astrocytes express P(2Y(1)), a receptor subtype stimulated by ATP and ADP and their 2MeS analogues, as well as P(2Y(2)) and P(2Y(4)), subtypes in rats for which ATP and UTP are equipotent. Transcripts for P(2Y(6)), a pyrimidine-preferring receptor, were not detected. ATP did not increase cyclic AMP levels, suggesting that P(2Y(11)), an ATP-preferring receptor, is not expressed or is not linked to adenylyl cyclase in rat cortical astrocytes. These signal transduction and RT - PCR experiments reveal differences in the activation of cRaf-1 by P(2Y) receptor agonists that are inconsistent with properties of the P(2Y(1)), P(2Y(2)) and P(2Y(4)) receptors shown to be expressed in astrocytes, i.e. ATP=UTP; ATP=2MeSATP, ADP. This suggests that the properties of the native P(2Y) receptors coupled to the Erk cascade differ from the recombinant P(2Y) receptors or that astrocytes express novel purine-preferring and pyrimidine-preferring receptors coupled to the ERK cascade.


Assuntos
Astrócitos/metabolismo , Ativadores de Enzimas/farmacologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Receptores Purinérgicos P2/metabolismo , Difosfato de Adenosina/farmacologia , Trifosfato de Adenosina/análogos & derivados , Trifosfato de Adenosina/farmacologia , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/enzimologia , Células Cultivadas , Córtex Cerebral/citologia , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/enzimologia , MAP Quinase Quinase Quinases/metabolismo , Proteína Quinase 3 Ativada por Mitógeno , Proteínas Serina-Treonina Quinases/biossíntese , Proteínas Proto-Oncogênicas c-raf/biossíntese , Agonistas do Receptor Purinérgico P2 , Ratos , Ratos Endogâmicos F344 , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tionucleotídeos/farmacologia , Uridina Trifosfato/farmacologia
16.
Hunan Yi Ke Da Xue Xue Bao ; 23(6): 558-60, 1998.
Artigo em Chinês | MEDLINE | ID: mdl-10806768

RESUMO

Endoscopic variceal ligation combined with partial splenic embolization (EVL-PSE) was performed in a group of 13 patients with esophageal variceal bleeding and hypersplenism due to portal hypertension from January 1997 to March 1998. PSE was performed one to two weeks before or one week after initial EVL, and a range of 30% to 60% of the splenic parenchyma was embolized. Repeated EVL was performed at two week intervals until the varices were eradicated. Active bleeding in the nine patients was successfully controlled and all the varices of the 13 patients were eradicated after EVL-PSE. Eradication of the varices required two to five(mean 3.1) EVL sessions, follow-up ranging from 2 to 16 months(mean 6.9 months). In all but one case, no rebleeding occurred. All patients after PSE showed a good response on peripheral blood cell count and reduction of splenomegaly. No major complication or death related to the combination therapy was observed. Preliminary results in this study show that this combination therapy may result in more rapid eradication of the varices and reduce rebleeding after endoscopic variceal ligation. However, more data and studies may be necessary for further evaluation.


Assuntos
Embolização Terapêutica , Varizes Esofágicas e Gástricas/cirurgia , Hipertensão Portal/cirurgia , Esplenomegalia/terapia , Adulto , Idoso , Embolização Terapêutica/métodos , Endoscopia , Endoscopia Gastrointestinal , Varizes Esofágicas e Gástricas/etiologia , Feminino , Humanos , Hipertensão Portal/complicações , Hipertensão Portal/terapia , Ligadura , Masculino , Pessoa de Meia-Idade , Veia Esplênica/cirurgia
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