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1.
J Assist Reprod Genet ; 34(8): 999-1006, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28540437

RESUMO

PURPOSE: This study aims to describe the role of implementing good laboratory practices to improve in vitro fertilization (IVF) outcomes which are of great interest for practitioners dealing with infertility. METHODS: Certain modifications were introduced in May 2015 in our IVF laboratory like high-efficiency particulate air CODA system, steel furniture instead of wooden, use of new disinfectants like oosafe, and restriction of personnel entry along with avoidance of cosmetics like perfume to improve pregnancy rates. Volatile organic compound (VOC) meter reading was monitored at two time points and five different places in the laboratory to compare the embryonic development parameters before (group A: July 2014-April 2015) and after (group B: July 2015-April 2016) remodeling. RESULTS: The IVF outcomes from 1036 cycles were associated in this study. Reduction in VOC meter readings, enhanced air quality, improvement in blastocyst formation rate, implantation, and clinical pregnancy rate were observed in the laboratory after implementation of new facilities. Results illustrated that the attention must be focused on potential hazards which expose laboratories to elevated VOC levels. Blastocyst formation rate increased around 18%. Implantation rate, clinical pregnancy rate, and live birth rate increased by around 11, 10, and 8%, respectively. CONCLUSION: In conclusion, with proper engineering and material selection, we have been able to reduce chemical contamination and adverse effects on culture with optimized IVF results. SUPPORT: None.


Assuntos
Blastocisto/citologia , Implantação do Embrião/fisiologia , Compostos Orgânicos Voláteis/metabolismo , Adulto , Coeficiente de Natalidade , Blastocisto/metabolismo , Transferência Embrionária/métodos , Desenvolvimento Embrionário/fisiologia , Feminino , Fertilização in vitro/métodos , Humanos , Infertilidade/metabolismo , Infertilidade/fisiopatologia , Laboratórios , Gravidez , Taxa de Gravidez
2.
ISA Trans ; 62: 333-48, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26876377

RESUMO

In this paper, an enhanced low-voltage ride-through (LVRT) performance of a grid connected doubly fed induction generator (DFIG) has been presented with the usage of stator dynamic composite fault current limiter (SDCFCL). This protection circuit comprises of a suitable series resistor-inductor combination and parallel bidirectional semiconductor switch. The SDCFCL facilitates double benefits such as reduction of rotor induced open circuit voltage due to increased value of stator total inductance and concurrent increase of rotor impedance. Both effects will limit rotor circuit over current and over voltage situation more secured way in comparison to the conventional scheme like the dynamic rotor current limiter (RCL) during any type of fault situation. The proposed concept is validated through the simulation study of the grid integrated 2.0MW DFIG.

3.
PLoS One ; 8(5): e64446, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23700477

RESUMO

Recurrent pregnancy loss (RPL) in polycystic ovary syndrome (PCOS), which occurs in ∼50% of total pregnancies is a frequent obstetric complication. Among the several hypotheses, insulin resistance (IR), obesity and hyperhomocysteinemia (HHcy) play significant role/s in RPL. This study was conducted to assess the link between elevated levels of homocysteine and IR in PCOS-associated women with RPL in Kolkata, India. A retrospective study was conducted of one hundred and twenty six PCOS women (<30 years) who experienced two or more spontaneous abortions during the first trimester presenting to Institute of Reproductive Medicine (IRM) in Kolkata during the period of March 2008 through February 2011. One hundred and seventeen non-PCOS subjects with matching age range were randomly chosen as controls. Incidence of HHcy and IR was 70.63% (n = 89) and 56.34% (n = 71), respectively, in RPL-affected PCOS population which was significantly higher (p<0.04; p<0.0001) when compared to the non-PCOS set (HHcy: 57.26%; IR: 6.83%). Rates of miscarriage were significantly higher (p<0.008; p<0.03) in hyperhomocysteinemia-induced miscarriage when compared to the normohomocysteinemic segment (PCOS: 70.63% vs.29.36% & non-PCOS: 57.26% vs. 42.73%) along with the insulin resistant (p<0.04; p<0.0001) population (PCOS: 70.63% vs. 56.34% & non-PCOS: 57.26% vs. 6.83%) in both groups. A probabilistic causal model evaluated HHcy as the strongest plausible factor for diagnosis of RPL. A probability percentage of 43.32% in the cases of HHcy- mediated RPL suggests its increased tendency when compared to IR mediated miscarriage (37.29%), further supported by ROC-AUC (HHcy: 0.778vs. IR: 0.601) values. Greater susceptibility towards HHcy may increase the incidence for miscarriage in women in India and highlights the need to combat the condition in RPL control programs in the subcontinent.


Assuntos
Aborto Habitual/etiologia , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/metabolismo , Adulto , Feminino , Humanos , Hiper-Homocisteinemia/complicações , Hiper-Homocisteinemia/metabolismo , Resistência à Insulina , Gravidez , Prognóstico , Curva ROC , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
4.
Biol Trace Elem Res ; 152(1): 9-15, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23322284

RESUMO

Insulin resistance is a very common associate of polycystic ovary syndrome (PCOS). Pathophysiology in relation with the essential elements including copper, magnesium, zinc, manganese, chromium, and calcium has been reported in women with insulin resistance. This prospective study was designed to explore whether the women with PCOS do exhibit altered serum element levels in association with/without insulin resistance. One hundred and thirty-two women with PCOS and forty-six control women were studied. Women with PCOS were further divided based on the presence of insulin resistance (insulin resistant: n = 50; non-insulin resistant: n = 82). In all women, basal levels of gonadotropins, prolactin, testosterone, insulin, glucose, and the six different elements were measured. Serum levels of testosterone (p < 0.001), luteinizing hormone (p < 0.05), and fasting insulin (p < 0.004) were significantly higher in the PCOS population compared to controls as well as PCOS women without insulin resistance. Women with PCOS exhibited a significantly high calcium (p < 0.04) and lower manganese levels (p < 0.002) when compared to controls. However, the PCOS women with insulin resistance exhibited significantly lower serum levels of magnesium and chromium (p < 0.04), in addition to higher levels of zinc and copper (p < 0.04). The differences in calcium (p < 0.03) and manganese levels (p < 0.0001) became aggravated with the presence of insulin resistance when compared to control as well as PCOS women without insulin resistance. In PCOS-associated insulin resistance, circulating serum magnesium (r = -0.31; p < 0.03) and chromium (r = -0.38; p < 0.006) status significantly correlated with fasting insulin levels. We conclude that imbalanced element status may be a key foundation for insulin resistance in PCOS. The findings in this study should be investigated with further trials in order to obtain new insights into PCOS.


Assuntos
Resistência à Insulina , Síndrome do Ovário Policístico/sangue , Oligoelementos/sangue , Adulto , Glicemia/análise , Cálcio/sangue , Cromo/sangue , Cobre/sangue , Jejum/sangue , Feminino , Gonadotropinas/sangue , Humanos , Insulina/sangue , Hormônio Luteinizante/sangue , Magnésio/sangue , Manganês/sangue , Síndrome do Ovário Policístico/fisiopatologia , Prolactina/sangue , Estudos Prospectivos , Testosterona/sangue , Zinco/sangue
5.
Hum Reprod ; 21(9): 2403-7, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16861701

RESUMO

BACKGROUND: The impact of oxidative stress in female reproduction is not clear. Contradictory reports on the effect of various oxidative stress markers on follicular fluid, oocytes and embryo quality and fertilization potential exist. The objectives of this study were to examine reactive oxygen species (ROS) levels in follicular fluid of women undergoing IVF and to relate these levels to embryo formation and quality. METHODS AND RESULTS: A total of 208 follicular fluid samples were obtained from 78 women undergoing controlled ovarian stimulation and analysed for ROS and lipid peroxidation (LPO). These samples were divided into groups I and II which represented follicular fluid containing grade III and grade II oocytes, respectively. These groups were further subdivided into groups IA, IB, IIA and IIB according to embryo quality. Subgroups IA and IIA consisted of follicular fluid samples corresponding to grade I/II embryo formation. Subgroups IB and IIB represented fertilization failure/pro-nucleolus (PN) arrest/grade III embryos. No significant correlation was observed in ROS levels on comparing groups I and II (P > 0.05). However, ROS levels were observed to be significantly different on comparing groups IA and IB (P < or = 0.01) and groups IIA and IIB (P < or = 0.05). LPO levels further supported our results. CONCLUSION: ROS levels in follicular fluid appear to play a significant role in embryo formation and quality.


Assuntos
Técnicas de Cultura Embrionária , Fertilização in vitro/instrumentação , Fertilização in vitro/métodos , Líquido Folicular/metabolismo , Espécies Reativas de Oxigênio , Estruturas Embrionárias/metabolismo , Feminino , Humanos , Peroxidação de Lipídeos , Oócitos/metabolismo , Folículo Ovariano/metabolismo , Estresse Oxidativo , Gravidez , Fatores de Tempo
6.
Hum Reprod ; 19(9): 2031-5, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15217999

RESUMO

BACKGROUND: Use of letrozole, a selective inhibitor of aromatase, reduces the gonadotrophin dose required to induce follicular maturation. We evaluated whether incorporation of letrozole could be an effective low-cost IVF protocol for poor responders. METHODS: A randomized, controlled, single-blind trial was conducted in the Assisted Reproduction Unit, Institute of Reproductive Medicine, Kolkata, India. Thirty-eight women with a history of poor ovarian response to gonadotrophins were recruited. Thirteen women (Let-FSH group) received letrozole 2.5 mg daily from day 3-7, and recombinant FSH (rFSH) 75 IU/day on days 3 and 8; and 25 women (GnRH-ag-FSH group) underwent long GnRH agonist protocol and stimulated with rFSH (300-450 IU/day). Ovulation was triggered by 10,000 IU of HCG followed by IVF-embryo transfer. The main outcome measures were total dose of rFSH (IU/cycle), terminal estradiol (E2) (pg/ml), numbers of follicles, oocytes retrieved and transferable embryo, endometrial thickness (mm), and pregnancy rate. RESULTS: Compared with the GnRH-ag-FSH group (2865 +/- 228 IU), the Let-FSH group (150 +/- 0 IU) received a significantly (P < 0.001) lower total dose of FSH. Except for terminal E2, which was significantly higher (P < 0.001) in the GnRH-ag-FSH group (380 +/- 46 pg/ml) than the Let-FSH group (227 +/- 45 pg/ml), the treatment outcomes in all other respects, including pregnancy rate, were statistically comparable. CONCLUSIONS: Adjunctive use of letrozole may form an effective means of low-cost IVF protocol in poorly responding women.


Assuntos
Inibidores da Aromatase/economia , Inibidores da Aromatase/uso terapêutico , Controle de Custos , Fertilização in vitro/economia , Gonadotropinas/uso terapêutico , Nitrilas/economia , Nitrilas/uso terapêutico , Ovário/efeitos dos fármacos , Triazóis/economia , Triazóis/uso terapêutico , Adulto , Gonadotropina Coriônica/uso terapêutico , Relação Dose-Resposta a Droga , Resistência a Medicamentos , Transferência Embrionária , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/administração & dosagem , Hormônio Foliculoestimulante/uso terapêutico , Hormônio Liberador de Gonadotropina/agonistas , Humanos , Letrozol , Gravidez , Taxa de Gravidez , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/uso terapêutico , Método Simples-Cego , Resultado do Tratamento
7.
Hum Reprod ; 18(10): 2031-8, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14507817

RESUMO

BACKGROUND: The pathophysiological mechanisms underlying premature ovarian failure (POF) are largely unknown. Our objective was to develop a working animal model to explore the pathogenesis of POF. Since galactosaemic women eventually develop POF, we evaluated the potential of experimental galactose toxicity as the proposed model. METHODS: Pregnant rats were fed pellets supplemented with or without 35% galactose from day 3 of conception continuing through weaning of the litters. Female offspring were evaluated for serum levels of galactose and galactose-1-phosphate, growth rate, onset of puberty, reproductive cyclicity, ovarian complement of follicles, hypothalamo-pituitary-ovarian function and follicular response to gonadotrophins. RESULTS: Galactose toxicity delayed the onset of puberty and developed a state of hypergonadotrophic hypoestrogenism. The characteristic low FSH levels at weaning followed by pubertal spurts of gonadotrophins and estradiol (E(2)) secretion of the controls was replaced by a sustained high level of FSH and a low level of E(2) under galactose toxicity. The ovary developed with apparently normal or deficient complement of follicles. Ovarian response to exogenous gonadotrophin stimulation was blunted, but the response improved significantly when the stimulation was preceded by pituitary desensitization. CONCLUSION: Experimental galactose toxicity may serve as a model for exploring some of the basic tenets of POF.


Assuntos
Galactose/intoxicação , Insuficiência Ovariana Primária/induzido quimicamente , Envelhecimento , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Estradiol/sangue , Feminino , Galactose/sangue , Galactosefosfatos/sangue , Gonadotropinas/sangue , Ovário/patologia , Indução da Ovulação , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Insuficiência Ovariana Primária/sangue , Insuficiência Ovariana Primária/patologia , Ratos , Ratos Sprague-Dawley , Superovulação , Vagina/fisiopatologia
8.
Hum Reprod ; 18(2): 276-82, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12571162

RESUMO

BACKGROUND: In rats, prenatal exposure to high concentrations of galactose may contribute to a condition that is equivalent to the premature ovarian failure (POF) component of human galactosaemia. We investigated if development of POF under experimental galactosaemia-like conditions was attributed to impaired germ cell migration. METHODS: Pregnant rats were fed pellets supplemented with, or without, 35% galactose from day 3 of conception continuing through parturition. Between days 12-15, embryos from one uterine horn were dissected out. Primordial germ cells (PGC) were histochemically localized and counted on the basis of binding of Dolichos biflorus agglutinin, a lectin specific for terminal N-acetylgalactosamine (GalNAc), to the surface glycoconjugate of the germ cells. The embryos from the other uterine horn were maintained until parturition. Liver activity of uridine diphosphate galactose 4-epimerase, the enzyme involved at multiple steps in the process of synthesis of GalNAc, was assayed in 1-2 day old female pups. RESULTS: The numbers of PGC at the day-specific sites on all days of examination were significantly lower (P

Assuntos
Galactose/administração & dosagem , Galactose/efeitos adversos , Galactosemias/etiologia , Células Germinativas/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal , Insuficiência Ovariana Primária/etiologia , Animais , Contagem de Células , Movimento Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Galactosemias/complicações , Células Germinativas/patologia , Gônadas/patologia , Fígado/enzimologia , Masculino , Gravidez , Ratos , UDPglucose 4-Epimerase/antagonistas & inibidores , UDPglucose 4-Epimerase/metabolismo
9.
Biochem Biophys Res Commun ; 300(3): 686-93, 2003 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-12507504

RESUMO

Hyaluronan binding protein 1 (HABP1) is a ubiquitously expressed multifunctional phospho-protein that interacts with a wide range of ligands and is implicated in cell signalling. Recently, we have reported that HABP1 is an endogenous substrate for MAP kinase and upon mitogenic stimulation it is translocated to the nucleus in a MAP kinase-dependent manner (Biochem. Biophys. Res. Commun. 291(4) (2002) 829-837). This prompted us to investigate the role of HABP1 in cell growth or otherwise in low MAP kinase background. We demonstrate that HABP1, when overexpressed in normal rat skin fibroblasts, remained in the cytosol, primarily concentrated around the nuclear periphery. However, HABP1 overexpressing cells showed extensive vacuolation and reduced growth rate, which was corrected by frequent medium replenishment. Further investigation revealed that HABP1 overexpressing cells undergo apoptosis, as detected by TUNEL assay, induction of Bax expression, and FACS analysis, and they failed to enter into the S-phase. Periodic medium supplementation prevented these cells from undergoing apoptotic death. We also demonstrate that upon induction of apoptosis in HeLa cells by cisplatin, HABP1 level is upregulated, indicating a correlation between HABP1 and cell death in a normal cellular environment.


Assuntos
Fibroblastos/metabolismo , Receptores de Hialuronatos/biossíntese , Animais , Apoptose/efeitos dos fármacos , Proteínas de Transporte , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Meios de Cultura/farmacologia , Citoplasma/metabolismo , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Células HeLa , Humanos , Receptores de Hialuronatos/farmacologia , Proteínas Mitocondriais , Ratos , Estresse Fisiológico/metabolismo , Fatores de Tempo
10.
Biochem Biophys Res Commun ; 291(4): 829-37, 2002 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-11866440

RESUMO

The role of hyaluronan binding protein 1 (HABP1) in cell signaling was investigated and in vitro kinase assay demonstrated that it is a substrate for MAP kinase. Phosphorylation of endogenous HABP1 was also observed following treatment of J774 cells with PMA. HABP1 was coimmunoprecipitated with activated ERK, confirming their physical interaction in the cellular context. Upon PMA stimulation of normal rat fibroblast (F111) and transformed (HeLa) cells, the HABP1 level in the cytoplasm gradually decreased with a parallel increase in the nucleus. In HeLa cells, within 6 h of PMA treatment, HABP1 was completely translocated to the nucleus, which was prevented by PD98059, a selective inhibitor of ERK. We also observed that the nuclear translocation of HABP1 is concurrent with that of ERK, suggesting that ERK activation is a requirement for the translocation of HABP1. It is thus established for the first time that HABP1 is a substrate for ERK and an integral part of the MAP kinase cascade.


Assuntos
Núcleo Celular/metabolismo , Receptores de Hialuronatos/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Proteínas de Transporte , Linhagem Celular , Células HeLa , Humanos , Microscopia de Fluorescência , Proteínas Mitocondriais , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno , Mitógenos/farmacologia , Fosforilação , Acetato de Tetradecanoilforbol/farmacologia
11.
J Exp Clin Cancer Res ; 21(4): 563-8, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12636103

RESUMO

The anticancer effect of black tea (BT) and its polyphenols theaflavin (TF) and thearubigin (TR) has been evaluated on U-937 cell line, a myeloid leukemic cell line and on leukemic cells isolated from peripheral blood of chronic myeloid leukemia (CML) patients. In both types of cells, cell growth inhibition was observed 24 hrs after treatment with BT, TF and TR. MTT assay showed growth inhibition of metabolically active cells and inhibition of DNA synthesis was observed by 3H-Thymidine incorporation after treatment with the compounds. In all cases TF and TR were more effective than BT, suggesting that these are possibly the active components in BT responsible for its antileukemic activity. Superoxide dismutase (SOD), a free radical scavenger, was found to be increased by TF, whereas BT and TR lowered the level in comparison to the control. The present study is the first report of antileukemic effect of BT and its polyphenols.


Assuntos
Anticarcinógenos/toxicidade , Biflavonoides , Catequina/análogos & derivados , Divisão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fitoterapia , Extratos Vegetais/toxicidade , Chá , Catequina/isolamento & purificação , Catequina/farmacologia , Humanos , Cinética , Leucemia Mieloide , Fenóis/isolamento & purificação , Fenóis/farmacologia , Polifenóis , Superóxido Dismutase/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Chá/toxicidade , Células Tumorais Cultivadas
12.
J Virol ; 75(21): 10348-58, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11581403

RESUMO

Transcriptional activation of diverse cellular genes by the X protein (HBx) of hepatitis B virus (HBV) has been suggested as one of the mechanisms for HBV-associated hepatocellular carcinoma. However, such functions of HBx have been studied using transformed cells in culture and have not been examined in the normal adult hepatocytes, a natural host of HBV. Using an efficient hepatocyte-specific virus-based gene delivery system developed in our laboratory earlier, we studied the HBx action in vivo. We demonstrate that following virosome-mediated delivery of HBx DNA, a large population (>50%) of hepatocytes express the HBx protein in a dose-dependent manner, which induces a significant increase in the activity of extracellular signal-regulated kinases (ERKs) in the livers of HBx-transfected mice. Inhibition of HBx-induced ERK activation following intravenous administration of PD98059, a mitogen-activated protein kinase kinase kinase (MEK) inhibitor, confirmed the requirement for MEK in the activation of ERKs by HBx. Induction of ERK activity by HBx was sustained for up to 30 days. Interestingly, sustained activation of c-Jun N-terminal kinases (JNKs) for up to 30 days was also noted. Such constitutive ERK and JNK activation as a consequence of continued HBx expression also led to sustained stimulation of further downstream events, such as increased levels of c-Jun and c-Fos proteins along with the persistent induction of activator protein 1 binding activity. Taken together, our data suggest a critical role of these molecules in HBx-mediated cell transformation.


Assuntos
Hepatócitos/virologia , Proteínas Quinases JNK Ativadas por Mitógeno , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Transativadores/toxicidade , Fator de Transcrição AP-1/metabolismo , Animais , Carcinoma Hepatocelular/etiologia , DNA Viral/metabolismo , Ativação Enzimática , Feminino , Flavonoides/farmacologia , Hepatócitos/metabolismo , Neoplasias Hepáticas/etiologia , MAP Quinase Quinase 4 , Camundongos , Camundongos Endogâmicos BALB C , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-jun/biossíntese , Transativadores/genética , Proteínas Virais Reguladoras e Acessórias
13.
FEBS Lett ; 504(1-2): 59-64, 2001 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-11522297

RESUMO

The human hepatitis B virus X protein (HBx) is known as a dual-specificity transactivator stimulating the transcriptional machinery in the nucleus and signal transduction pathways in the cytoplasm. HBx-induced activation of mitogen-activated protein kinase (MAPK) signaling cascades is considered to play an important role in hepatitis B virus-mediated hepatocarcinogenesis. Herein, we have identified the regions of HBx that are crucial for activating such signaling cascades in vivo. A truncated mutant incorporating regions C-E (amino acids 58-140) was as effective as the full-length HBx in activating MAPKs and enhancing activator protein-1 binding activity. While deletion of region C (amino acids 58-84) or D (amino acids 85-119) led to a drastic loss of function, region E (amino acids 120-140) was dispensable for the activation of signaling cascades. Overall, these findings provide the first evidence for the requirement of domain 58-119 of HBx in transmitting mitogenic signals to the nucleus in vivo.


Assuntos
Fígado/enzimologia , Sistema de Sinalização das MAP Quinases , Transativadores/metabolismo , Animais , Sequência de Bases , Western Blotting , Primers do DNA , Ativação Enzimática , Fígado/citologia , Camundongos , Mutação , Fosforilação , Transdução de Sinais , Transativadores/química , Transativadores/genética , Fator de Transcrição AP-1/metabolismo , Proteínas Virais Reguladoras e Acessórias
14.
Mol Cell Biochem ; 217(1-2): 13-20, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11269656

RESUMO

Hypertrophic stimulation of cardiac myocytes results in rapid induction of a number of transcription factors, including members of the AP-1 family, which is followed by a programmed alteration in the pattern of gene expression. In the ventricular cardiocytes there is re-expression of the fetal atrial natriuretic factor (ANF) gene and upregulation of its myosin light chain-2 (MLC-2v). The mechanism(s) by which the induction ofAP-1 is coupled to the promoters of these target genes is largely unknown. In this report, we demonstrate that in transient co-transfection assay, c-Jun inhibited while Jun B stimulated the MLC-2v promoter activity. Mutant c-Jun recombinants, in which the activation domains were deleted, still remained inhibitory, but a specific mutation in the leucine zipper, which changes the alignment of Jun with its dimerization partner, caused a reversal of its effect on the target MLC-2v promoter. Based on these findings, we propose that in chicken cardiac myocytes, the regulation of MLC-2v promoter by Jun may occur via its interaction with other proteins, possibly of the leucine zipper family.


Assuntos
Miosinas Cardíacas , Regulação da Expressão Gênica , Miocárdio/citologia , Miocárdio/metabolismo , Cadeias Leves de Miosina/genética , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-jun/metabolismo , Fator de Transcrição AP-1/metabolismo , Animais , Células Cultivadas , Embrião de Galinha , Dimerização , Genes jun , Zíper de Leucina , Mutação , Estrutura Terciária de Proteína , Proteínas Proto-Oncogênicas c-jun/química , Transfecção
15.
FEMS Microbiol Lett ; 180(2): 213-9, 1999 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-10556714

RESUMO

We previously demonstrated that the CDR1 gene, encoding a multidrug transporter in Candida albicans, is differentially upregulated by various drugs and steroids. In order to get an insight into the molecular basis of the induction of this gene we analyzed its promoter region. The transcription start site was mapped to 63 nucleotides upstream of the initiating ATG. Reporter assays revealed the presence of four upstream activating and four upstream repressing sequence domains along the entire promoter. Like the native gene, promoter-luciferase recombinants showed enhanced activity in response to various stresses like drugs, human steroid hormones and heavy metals. Mutational analysis demonstrated that while the proximal promoter (-345/+1) contains all the regulatory domains required for its induction by various other stresses, the miconazole response is mediated via the distal promoter (-857/-1147), harboring an AP-1 site. The involvement of the AP-1 element in mediating the latter effect was evident by an increase in AP-1 binding activity following miconazole treatment.


Assuntos
Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Proteínas de Membrana Transportadoras , Miconazol/farmacologia , Sequência de Bases , Candida albicans/genética , Resistência Microbiana a Medicamentos , Resistência a Múltiplos Medicamentos , Eletroporação , Proteínas Fúngicas/metabolismo , Deleção de Genes , Genes Fúngicos , Genes MDR , Humanos , Dados de Sequência Molecular , Mutação , Regiões Promotoras Genéticas/genética , Análise de Sequência de DNA , Fator de Transcrição AP-1/genética , Fator de Transcrição AP-1/metabolismo , Transcrição Gênica , Transformação Genética
16.
Biol Reprod ; 60(4): 954-8, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10084971

RESUMO

The effects of pelvic endometrial implants on the overall reproductive potential of female rats were investigated. After homologous transplantation in the peritoneum, the ectopic endometrium developed into highly vascularized nodes that gradually increased in mass until the 9th week postsurgery and then plateaued. In the presence of these implants, overall reproductive function was adversely affected. The effect was of greatest magnitude during 50-70 days posttransplantation. As compared with values in corresponding controls, ovulation was reduced by 43% (6 of 14) (p < 0.05), mating rate was reduced by 44% (12 of 27) (p < 0.025), and premature termination of pregnancy occurred in 34% (5 of 15) of rats. Wastage of pregnancy, which included complete termination or reduction of fetal number, occurred during the postimplantation course of gestation. Furthermore, 100% of the rats with transplants failed to respond to the copulomimetic stimulation for the induction of pseudopregnancy (p < 0.01, compared with corresponding controls). However, on exposure to vasectomized males, 46% (6 of 13) of these rats exhibited development of pseudopregnancy (p < 0.05, compared with corresponding group receiving copulomimetic stimulation). Increased rate of mating failure and differential pseudopregnancy rates after copulomimetic and natural cervical stimulation suggest that the rats with endometrial explants possibly had an absence or a short appearance of behavioral estrus. Hormonal assessment during the preovulatory phase showed a tendency toward lower mean levels of preovulatory estradiol and significantly lower LH (p < 0.01) and progesterone (p < 0.01) concentrations. The adversely affected reproductive functions may be a secondary consequence of these altered endocrine milieus.


Assuntos
Endométrio/transplante , Reprodução/fisiologia , Aborto Espontâneo , Animais , Copulação , Estradiol/sangue , Feminino , Hormônio Luteinizante/sangue , Ovulação , Peritônio , Gravidez , Progesterona/sangue , Pseudogravidez , Ratos , Ratos Sprague-Dawley , Transplante Heterotópico
17.
Artigo em Inglês | MEDLINE | ID: mdl-9253882

RESUMO

A total of 395 drug addicts from Nagaland, India during 1992-1993 were studied. Of these, 331 (83.8%) were primary abusers of heroin. Mean age of the group was 21.8 years +/- SD 3.84. Of these 5.2% were females. The majority were unmarried (92.1%) and 52% had completed 10 years of schooling. Drug-related school dropout rate was 72.8%. Unemployment was predominant (90.3%) in the group, of which most were never employed. Christianity was the main religion (90.9%) of the group. The mean age at first use of heroin was 17.6 years +/- SD 3.68. The mean duration of dependence on heroin was 4.4 years +/- SD 2.8. Heroin was injected by 80.9% subjects. Friends were the main source of introduction. Concurrent use of tranquilizers and codeine containing cough syrups was prevalent in the event of a short supply of heroin. The involvement of young, unemployed, unmarried persons in heroin addiction; widespread prevalence of the injection route and needle sharing; chronicity of heroin dependence; paucity of specialized treatment avenues and proximity to the Golden Triangle facilitating illicit traffic, have contributed to emergence of heroin addiction as a major public health problem in Nagaland.


Assuntos
Dependência de Heroína/epidemiologia , Adolescente , Adulto , Fatores Etários , Criança , Escolaridade , Feminino , Humanos , Índia/epidemiologia , Masculino
19.
J Mol Cell Cardiol ; 28(9): 1901-10, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8899549

RESUMO

Latissimus dorsi muscle (LDM) transformation following chronic stimulation is the critical requirement for its use in cardiac assist procedures. In order to identify one or two molecular markers that can be used to effectively monitor the LDM transformation, the modulation in the expression of creatine kinase (CK) and phospholamban (PLB) genes by semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR) was examined. Continuous in situ stimulation of left LDM was performed in four dogs for a period of 10 weeks after a vascular delay period of 2 weeks following surgery. For RT-PCR, gene-specific radiolabeled primers and equal amounts of cDNA synthesized from total RNA extracted from the LDM biopsies obtained at 4, 7, and 10 weeks of stimulation were used. A 2.6-fold increase in creatine kinase (brain type) (CK-B) mRNA was observed at transformed LDM compared to the control (P = 0.004) following 10 weeks of stimulation. On the contrary, a 30% decline was observed in creatine kinase (muscle type) (CK-M) mRNA level. An increase up to eight-fold was also observed in PLB mRNA in stimulated LDM compared to the contralateral muscle (P = 0.002). The PLB mRNA level in transformed LDM reached plateau and became comparable to that of normal heart after 7 weeks of stimulation. However, a sustained increase in CK-B mRNA level was observed until 10 weeks of stimulation. The level of beta-actin mRNA used as control remained the same in both stimulated and control samples. Thus the increase in CK-B and PLB mRNA and downregulation of CK-M mRNA in transformed LDM, demonstrated here by RT-PCR, indicate a switch from anaerobic to aerobic potential of transformed LDM along with a change towards slow-twitch phenotype and provide valuable markers to monitor the effectiveness of muscle transformation in cardiomyoplasty.


Assuntos
Adenosina Trifosfatases/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Creatina Quinase/metabolismo , Músculo Esquelético/metabolismo , Actinas/metabolismo , Adenosina Trifosfatases/genética , Animais , Biópsia , Creatina Quinase/genética , Cães , Ativação Enzimática , Músculo Esquelético/fisiologia , Reação em Cadeia da Polimerase/métodos , RNA Mensageiro/análise , Fatores de Tempo
20.
J Assist Reprod Genet ; 13(5): 374-80, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8739051

RESUMO

PURPOSE: Our purpose was to evaluate the IVF-ET outcome in patients who did not achieve timely pituitary-ovarian suppression following "long"-protocol GnRH agonist (GnRH-a) administration. METHODS: A retrospective analysis was done on 96 IVF treatment cycles characterized by a delayed response (DR) to long-protocol GnRH-a treatment. The study included those patients who either achieved ovarian suppression (E2 < or = 110 pM) despite an elevated LH level (group DR-A) or had pituitary desensitization (LH < or = 1.5 IU/L) without ovarian suppression (group DR-B) on day 12 of GnRH-a treatment but needed an extended course of GnRH-a treatment to achieve complete suppression. These patients had gonadotropin stimulation either from day 12, despite an elevated level of LH (subgroup DR-A1; n = 13) or elevated E2 levels (subgroup DR-B1; n = 9), or after achieving a complete hypogonadotropic-hypopgonadal state following an extended course of GnRH-a treatment [subgroups DR-A2 (n = 46) and DR-B2 (n = 28)]. The outcome was compared with that of 88 cycles of normal responders (group NR) who had pituitary-ovarian suppression by day 12 day GnRH-a administration. RESULTS: Ovarian response and pregnancy rates in subgroups DR-A1 and DR-A2 were statistically not different and comparable to those in the NR group. In subgroups DR-B1 and DR-B2, E2 response and rates of oocyte retrieval and pregnancy were significantly lower than those in the other groups, but fertilization and cleavage rates were similar. The requirement of gonadotropin for ovarian stimulation was comparatively higher in subgroup DR-A2 and both DR-B subgroups. CONCLUSIONS: There was no treatment cancellation in group NR and both DR-A subgroups, but 22% of the cycles in DR-B1 and 14% of the cycles in DR-B2 were canceled due to poor ovarian response. It therefore appears that during long-protocol pituitary desensitization, the post-GnRH-a level of serum E2, rather than LH, better predicts IVF-ET outcome.


Assuntos
Fertilização in vitro , Hormônio Liberador de Gonadotropina/agonistas , Hormônio Liberador de Gonadotropina/farmacologia , Ovário/efeitos dos fármacos , Adulto , Transferência Embrionária , Estradiol/sangue , Feminino , Previsões , Humanos , Hormônio Luteinizante/sangue , Oócitos/fisiologia , Hipófise/efeitos dos fármacos , Gravidez , Estudos Retrospectivos , Resultado do Tratamento
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