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1.
Indian J Sex Transm Dis AIDS ; 39(1): 1-6, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30187018

RESUMO

Erectile dysfunction (ED) is a common complication in patients with diabetes mellitus (DM). Sildenafil, a phosphodiesterase-5 inhibitor, is commonly used in patients with ED. This meta-analysis was planned to determine the strength of evidence to assess the efficacy and tolerability of sildenafil in patients with DM-associated ED. Electronic searches were carried out to identify randomized controlled trials (RCTs) which reported clinical efficacy of sildenafil in patients with DM-associated ED. Data were extracted and methodological quality was assessed. Relative Risk (RR) with 95% confidence intervals (CIs) was estimated for the dichotomous outcomes, and the mean difference with 95% CI was estimated for continuous data. Eight randomized controlled trials (RCTs) involving 1172 patients met with our inclusion criteria. In comparison to placebo, sildenafil significantly improved the overall sexual performance in patients of ED associated with DM with relative risk (RR) of answering "yes" to global efficiency question being 3.99 (95% CI: 2.58-6.18) compared to placebo. The rate of discontinuation due to treatment-related adverse reactions was 2.4% in sildenafil arm with RR of 2.67 (95% CI: 0.74-9.62). Sildenafil is an effective and safe medication for the treatment of ED associated with DM.

2.
J Postgrad Med ; 58(2): 112-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22718054

RESUMO

BACKGROUND: Drug-resistant typhoid fever is a major clinical problem globally. Emergence of multidrug-resistant (MDR) S. Typhi has complicated therapy by limiting treatment options. OBJECTIVES: A meta-analysis was planned to determine the strength of evidence supporting use of azithromycin over the alternate drugs available for treatment of uncomplicated typhoid fever. MATERIALS AND METHODS: Studies were identified using electronic database such as MEDLINE and other data at the National Library of Medicine assessed using PUBMED search engine as well as Cochrane Clinical Trial Register. Randomized control trials (RCTs) comparing azithromycin with chloramphenicol, fluoroquinolones and cephalosporins in culture-proven enteric fever were included. Data was extracted and methodological quality was assessed. Risk ratio (RR) with 95% confidence intervals was estimated for the dichotomous outcomes and mean difference (MD) with 95% confidence was estimated for continuous data. Primary outcomes studied were clinical failure (CF), microbiological failure, and relapse. RESULTS: A total of seven RCTs involving 773 patients met with our inclusion criteria. In comparison to older fluoroquinolones, azithromycin is marginally better in reducing the chance of CF with RR 0.46 (95% CI 0.25-0.82), while in comparison to ceftriaxone, it significantly reduced the chance of relapse with RR 0.1 (95% CI 0.01- 0.76). There were no serious adverse events reported in any of the trials. CONCLUSION: Azithromycin can be recommended as a second-line drug in MDR typhoid fever, however, large trials involving pediatric age group patients are recommended to arrive at a definite conclusion.


Assuntos
Antibacterianos/uso terapêutico , Azitromicina/uso terapêutico , Salmonella typhi/efeitos dos fármacos , Febre Tifoide/tratamento farmacológico , Antibacterianos/efeitos adversos , Azitromicina/efeitos adversos , Cefalosporinas/efeitos adversos , Cefalosporinas/uso terapêutico , Cloranfenicol/efeitos adversos , Cloranfenicol/uso terapêutico , Intervalos de Confiança , Fluoroquinolonas/efeitos adversos , Fluoroquinolonas/uso terapêutico , Humanos , Razão de Chances , Ensaios Clínicos Controlados Aleatórios como Assunto , Salmonella typhi/isolamento & purificação , Resultado do Tratamento , Febre Tifoide/microbiologia
3.
Indian J Dermatol ; 55(2): 198-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20606897

RESUMO

BACKGROUND: Toenail onychomycosis is a challenge for clinicians to treat. While both Itraconazole and terbinafine have proven to be effective against onychomycosis, very little is known about their comparative efficacy in achieving mycological and clinical cure. AIM: The purpose of this meta-analysis is to compare the efficacy of continuous terbinafine with intermittent itraconazole in the treatment of toenail onychomycosis. MATERIAL AND METHODS: all RCTs comparing continuous terbinafine with intermittent itraconazole were identified from PUBMED and BIDS electronic database. RESULTS: analysis of total eight trials including 1181 patients state that treatment with continuous terbinafine is more likely to produce mycological and clinical cure compared to intermittent itraconazole with odds ratio 2.3(95% CI, 1.7 to 3.0 P<0.0001) CONCLUSION: though both itraconazole and terbinafine are well tolerated and highly effective drugs, continuous terbinafine is more effective than intermittent itraconazole at achieving mycological cure of toenail onychomycosis.

4.
Indian J Physiol Pharmacol ; 50(4): 409-15, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17402272

RESUMO

The objective of the present study was to evaluate the antidepressant action of Withania somnifera (WS) as well as its interaction with the conventional antidepressant drugs and to delineate the possible mechanism of its antidepressant action using forced swimming model in mice. Effect of different doses of WS, fluoxetine and imipramine were studied on forced swimming test induced mean immobility time (MIT). Moreover effect of WS 100 mg/kg, i.p. was observed at different time intervals. Effect produced by combination of sub therapeutic doses of WS with imipramine (2.5 mg/kg, i.p.) as well as fluoxetine (2.5 mg/kg, i.p.) were also observed. Effect of WS (100 mg/kg, i.p.) as well as combination of WS (37.5 mg/kg, i.p.) with either imipramine (2.5 mg/kg, i.p.) or fluoxetine (2.5 mg/kg, i.p.) were observed in mice pretreated with reserpine (2 mg/kg, i.p.) and clonidine (0.15 mg/kg, i.p.). Effects of prazosin (3 mg/kg, i.p.) or haloperidol (0.1 mg/kg, i.p.) pre-treatment were also observed on WS induced decrease in MIT. WS produced dose dependent decrease in MIT. Maximum effect in MIT was observed after 30 min of treatment with WS 100 mg/kg, i.p. Combination of WS (37.5 mg/kg, i.p.) with imipramine (2.5 mg/kg, i.p.) or fluoxetine (2.5 mg/kg, i.p.) also produced significant decrease in the MIT. Clonidine and reserpine induced increase in MIT, was significantly reversed by treatment with WS (100 mg/kg, i.p.) as well as combination of WS (37.5 mg/kg, i.p.) with either imipramine (2.5 mg/kg, i.p.) or fluoxetine (2.5 mg/kg, i.p.). Pre-treatment with prazosin but not haloperidol, significantly antagonized the WS (100 mg/kg, i.p.) induced decrease in MIT. It is concluded that, WS produced significant decrease in MIT in mice which could be mediated partly through a adrenoceptor as well as alteration in the level of central biogenic amines.


Assuntos
Antidepressivos , Atividade Motora/fisiologia , Natação/fisiologia , Withania/química , Agonistas alfa-Adrenérgicos/farmacologia , Antagonistas Adrenérgicos alfa/farmacologia , Animais , Antidepressivos de Segunda Geração/farmacologia , Antidepressivos Tricíclicos/farmacologia , Antipsicóticos/farmacologia , Clonidina/farmacologia , Interações Medicamentosas , Feminino , Fluoxetina/farmacologia , Imipramina/farmacologia , Masculino , Camundongos , Atividade Motora/efeitos dos fármacos , Extratos Vegetais/farmacologia , Prazosina/farmacologia , Reserpina/farmacologia
5.
Surg Endosc ; 19(1): 60-4, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15529194

RESUMO

BACKGROUND: Little is know about the effects of different insufflation gases on peritoneal pH during laparoscopy. However, these changes may influence the intracellular signalling system, resulting in altered cell growth or adhesiveness. The aim of this study was to determine the effects of carbon dioxide (CO(2)), nitrous oxide (N(2)O), and helium (He) on parietal and visceral peritoneal pH. The effect of different intraabdominal pressures on parietal and visceral peritoneal pH was also examined. METHODS: We conducted both an ambient gas study and a pressure study. For the ambient gas study, 20 pigs were divided into the following four groups: (a) CO(2), (b) He, (c) N(2)O, and (d) abdominal wall lift (Lift) laparoscopy. Parietal and visceral peritoneal pH were measured at 15 min intervals for 180 min. For the pressure study, 15 pigs were divided into the following three groups: (a) CO(2), (b) He, (c) N(2)O laparoscopy. Baseline values were established for parietal and visceral peritoneal pH. Intraabdominal pressure was then increased stepwise at 1-mmHg intervals to 15 mmHg. After pressure was maintained for 15 min at each setting, parietal and visceral peritoneal pH were measured. RESULTS: Ambient gas environment was the major determinant of parietal peritoneal pH. Carbon dioxide caused parietal peritoneal acidosis. Helium, N(2)O, and Lift caused alkalotic parietal peritoneal pH. Intraabdominal pressure had a minor effect on parietal peritoneal pH. At higher intraabdominal pressure (12-15 vs 5-8 mmHg), CO(2) caused a slight decrease in parietal peritoneal pH, whereas N(2)O and He caused a slight increase in parietal peritoneal pH. Visceral peritoneal pH remained relatively unaffected during all studies. CONCLUSIONS: Parietal peritoneal pH during laparoscopy was highly dependent on the ambient gas environment. The effect of intraabdominal pressure on parietal peritoneal pH was of minor significance. Carbon dioxide caused a slight worsening of parietal peritoneal acidosis at higher intraabdominal pressure, whereas, N(2)O, He, and Lift did not cause parietal peritoneal acidosis.


Assuntos
Dióxido de Carbono/farmacologia , Hélio/farmacologia , Laparoscopia , Óxido Nitroso/farmacologia , Peritônio/efeitos dos fármacos , Peritônio/metabolismo , Animais , Concentração de Íons de Hidrogênio , Período Intraoperatório , Pressão , Suínos
6.
Surg Endosc ; 18(10): 1498-503, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15791377

RESUMO

BACKGROUND: Carbon dioxide (CO(2)) is the most common gas used for insufflation in laparoscopy, but its effects on peritoneal physiology are poorly understood. This study looks at the changes in peritoneal and bowel serosal pH during CO(2) pneumoperitoneum, and whether heating and humidification with or without bicarbonate alters the outcomes. METHODS: Twenty-one pigs divided into four groups as follows: (1) standard (STD) laparoscopy (n = 5); (2) heated and humidified (HH) laparoscopy (n = 6); (3) heated and humidified with bicarbonate (HHBI) laparoscopy (n = 5); and (4) laparotomy (n = 5). Peritoneal pH, bowel serosal pH, and arterial blood gas (ABG) were obtained at 15-min intervals for 3 h. RESULTS: Severe peritoneal acidosis (pH range 6.59-6.74) was observed in all laparoscopy groups, and this was unaltered by heating and humidification or the addition of bicarbonate. Bowel serosal acidosis was observed in all laparoscopy groups with onset of pneumoperitoneum, but it recovered after 45 minutes. No significant changes in peritoneal or bowel serosal pH were observed in the laparotomy group. CONCLUSION: CO(2) pneumoperitoneum resulted in severe peritoneal acidosis that was unaltered by heating and humidification with or without bicarbonate. Alteration in peritoneal pH may conceivably be responsible for providing an environment favorable for tumor-cell implantation during laparoscopy.


Assuntos
Acidose/induzido quimicamente , Dióxido de Carbono/efeitos adversos , Doenças Peritoneais/induzido quimicamente , Pneumoperitônio Artificial/métodos , Animais , Bicarbonatos/uso terapêutico , Modelos Animais de Doenças , Temperatura Alta/uso terapêutico , Umidade , Índice de Gravidade de Doença , Suínos , Falha de Tratamento
7.
Blood Coagul Fibrinolysis ; 11(3): 255-9, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10870806

RESUMO

This open-label, emergency-use study evaluated the efficacy and safety of activated human coagulation factor VIIa (recombinant) (rFVIIa) (NovoSeven; Novo Nordisk Pharmaceuticals, Inc., New Jersey, USA) in treating limb-threatening joint or muscle bleeds in 17 patients with haemophilia A or B and six patients with acquired inhibitors to factor VIII or factor IX. All patients had previously failed on one or more alternative therapies. rFVIIa administration was effective or partially effective in controlling joint or muscle bleeds in 34 out of 35 (97%) bleeding episodes; in 23 patients, 14 of 17 (82%) muscle bleeds and 16 of 18 (89%) joint bleeds were effectively controlled. These findings suggest that rFVIIa is an effective and well-tolerated therapeutic option in the management of joint or muscle haemorrhage in patients with haemophilia and in patients with acquired inhibitors.


Assuntos
Fator VII/administração & dosagem , Hemofilia A/tratamento farmacológico , Hemofilia B/tratamento farmacológico , Adolescente , Adulto , Idoso , Anticorpos/sangue , Criança , Pré-Escolar , Extremidades/fisiopatologia , Fator IX/imunologia , Fator VIII/imunologia , Fator VIIa , Feminino , Hemofilia A/sangue , Hemofilia A/imunologia , Hemofilia A/fisiopatologia , Hemofilia B/sangue , Hemofilia B/imunologia , Hemofilia B/fisiopatologia , Hemorragia/tratamento farmacológico , Humanos , Lactente , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/administração & dosagem , Terapia de Salvação
8.
Gene ; 246(1-2): 197-207, 2000 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-10767541

RESUMO

Mammalian HMGI proteins belong to the high mobility group (HMG) of small non-histone nuclear proteins, and function as architectural factors to mediate structural changes in DNA. The HMGI family consists of three members: HMGI, HMGY and HMGI-C. As pseudogenes have complicated the genomic analysis of murine Hmgi(y), a mouse lambda FIX II genomic library was screened with an intron-specific probe to identify and characterize the authentic Hmgi(y) gene. The murine Hmgi(y) gene is 7.2kb long and contains four protein coding exons and two additional exons encoding part of the 5' untranslated region. Sequencing confirms that an alternative splicing site within exon 3 results in the two protein isoforms: Hmgi and Hmgy. Primer extension experiments revealed that at least three transcription start sites exist in the 5' end of the gene. It has been well established that the expression of both Hmgi-c and Hmgi(y) is readily detectable throughout embryogenesis. Unlike Hmgi-c, whose expression is restricted to embryogenesis, a Northern hybridization analysis showed low-level expression of Hmgi(y) in adult mouse tissues. Similarly, when tissues from newborn animals were examined, Hmgi(y) expression was readily detected at a level of intensity intermediate between that found in embryos and adults. Understanding the gene structure and expression pattern will provide important insights into the in-vivo function of Hmgi(y).


Assuntos
Genes/genética , Proteínas de Grupo de Alta Mobilidade/genética , Fatores de Transcrição/genética , Sequência de Aminoácidos , Animais , Animais Recém-Nascidos , Sequência de Bases , Northern Blotting , DNA/química , DNA/genética , DNA/isolamento & purificação , Éxons , Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Proteína HMGA1a , Íntrons , Masculino , Camundongos , Dados de Sequência Molecular , RNA/genética , RNA/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico , Distribuição Tecidual , Transcrição Gênica
9.
Am J Hematol ; 63(3): 109-13, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10679799

RESUMO

Eight patients with inhibitors to factor VIII (4 hemophilia A and 4 nonhemophilic) were treated with recombinant activated factor VII (rFVIIa) to control severe abdominal bleeding. The recombinant factor was supplied under an open-label, emergency-use program to patients previously unresponsive to one or more alternative therapies. Therapy with rFVIIa was administered for nine separate bleeding events; one patient was treated for two separate bleeding episodes. Patients were treated for an average of 9 days and received a mean total dose of 5.2 mg of rFVIIa for control of bleeding. Treatment was considered successful and hemostasis adequate in 7 of the 9 episodes (78%). Treatment with rFVIIa was partially successful in one other episode. Four patients in this series experienced serious adverse events; all the adverse events were considered unrelated to rFVIIa therapy. The results of this limited series indicate that rFVIIa is an effective means of managing life-threatening abdominal bleeding in individuals with hemophilia or acquired antibodies to factor VIII.


Assuntos
Abdome , Transtornos de Proteínas de Coagulação/tratamento farmacológico , Fator VII/uso terapêutico , Hemorragia/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Autoanticorpos/sangue , Criança , Transtornos de Proteínas de Coagulação/imunologia , Esquema de Medicação , Fator IX/imunologia , Deficiência do Fator VII/tratamento farmacológico , Fator VIII/imunologia , Fator VIIa , Feminino , Hemofilia A/tratamento farmacológico , Hemofilia B/tratamento farmacológico , Hemorragia/tratamento farmacológico , Hemorragia/imunologia , Humanos , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/uso terapêutico , Resultado do Tratamento
10.
Clin Cancer Res ; 5(11): 3488-99, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10589763

RESUMO

Six human ovarian cancer cell lines and samples of ascites cells isolated from 27 patients with stage III or IV ovarian papillary serous cystadenocarcinoma were studied individually to test whether recombinant human Mullerian inhibiting substance (rhMIS) acts via its receptor. To do these experiments, we scaled up production of rhMIS and labeled it successfully with biotin for binding studies, cloned the human MIS type II receptor for mRNA detection, and raised antibodies to an extracellular domain peptide for protein detection. These probes were first tested on the human ovarian cancer cell lines and then applied to primary ovarian ascites cells. rhMIS inhibited colony growth of five of six cell lines that expressed the human MIS type II receptor mRNA by Northern analysis while not inhibiting receptor-negative COS cells. Flow cytometry performed on MIS-sensitive ovarian cancer cell lines demonstrated specific and saturable binding of rhMIS (Kd = 10.2 nM). Ascites cells from 15 of 27 or 56% of patients tested bound biotinylated MIS (MIS-biotin) and, of the 11 that grew in soft agarose, 9 of 11 or 82% showed statistically significant inhibition of colony formation. Of the 15 patients who bound biotinylated MIS, mRNA was available for analysis from 9, and 8 of 9 expressed MIS type II receptor mRNA by reverse transcription-PCR, showing a statistically significant correlation, compared with binding, by chi2 analysis (P = 0.025). Solid ovarian cancers were positive for the MIS type II receptor protein by immunohistochemical staining, which colocalized with staining for antibody to CA-125 (OC-125). Thus, the detection of the MIS type I receptor by flow cytometry may be a useful predictor of therapeutic response to MIS and may be a modality to rapidly choose patients with late-stage ovarian cancer for treatment with MIS.


Assuntos
Cistadenocarcinoma/patologia , Glicoproteínas , Inibidores do Crescimento/farmacologia , Neoplasias Ovarianas/patologia , Receptores de Peptídeos/genética , Receptores de Peptídeos/metabolismo , Hormônios Testiculares/farmacologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Aminoácidos , Animais , Hormônio Antimülleriano , Ascite/genética , Ascite/patologia , Células COS , Divisão Celular/efeitos dos fármacos , Cistadenocarcinoma/genética , Feminino , Feto , Inibidores do Crescimento/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Ductos Paramesonéfricos , Neoplasias Ovarianas/genética , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/imunologia , Ratos , Receptores de Fatores de Crescimento Transformadores beta , Proteínas Recombinantes/metabolismo , Hormônios Testiculares/metabolismo , Testículo/embriologia , Testículo/metabolismo , Transfecção , Células Tumorais Cultivadas
11.
Mech Ageing Dev ; 107(1): 37-50, 1999 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-10197787

RESUMO

Intestinal ischemia/reperfusion (I/R) is a serious disorder that is prevalent in elderly patients. Reactive oxygen species are implicated in the pathogenesis of intestinal I/R injury. Reactive oxygen species are also implicated in cellular senescence and aging. To test the hypothesis that aging exacerbates intestinal I/R injury, the effects of intestinal I/R on tissue injury were compared between young (3 month old) and aged (12 month old) mice. Intestinal ischemia was induced by occluding the superior mesenteric artery with a microbulldog clamp. Reperfusion was initiated by removing the clamp. Mortality due to intestinal ischemia followed by reperfusion was significantly higher in aged mice. There were no differences in the baseline levels of malondialdehyde or myeloperoxidase activity (indicators of lipid peroxidation and neutrophil infiltration, respectively) between young and aged mice. Although intestinal I/R caused a significant increase in malondialdehyde levels and myeloperoxidase activity in aged mice, similar increases were also observed in young mice. There were no significant differences in the activities of antioxidant enzymes including superoxide dismutase, glutathione peroxidase and catalase between young and aged mice that underwent sham operation. Intestinal I/R caused a significant decrease in catalase activity only in aged mice. In conclusion, our results indicate that aged mice are more susceptible to mortality due to intestinal I/R and that an age-dependent decrease in catalase activity may contribute to the observed mortality.


Assuntos
Envelhecimento/metabolismo , Intestino Delgado/irrigação sanguínea , Isquemia/metabolismo , Traumatismo por Reperfusão/metabolismo , Envelhecimento/patologia , Animais , Intestino Delgado/metabolismo , Isquemia/mortalidade , Isquemia/patologia , Malondialdeído/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Peroxidases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Traumatismo por Reperfusão/mortalidade , Superóxido Dismutase/metabolismo , Taxa de Sobrevida
12.
Am J Physiol ; 273(4): C1130-5, 1997 10.
Artigo em Inglês | MEDLINE | ID: mdl-9357755

RESUMO

Superoxide dismutase (SOD) scavenges oxygen radicals that are implicated in the pathogenesis of intestinal ischemia-reperfusion injury. The effect of intestinal ischemia and reperfusion was investigated in transgenic mice overexpressing human Cu-Zn SOD. Ischemia was induced by occluding the superior mesenteric artery. Myeloperoxidase activity was determined as an index of neutrophil infiltration, and malondialdehyde levels were measured as an indicator of lipid peroxidation. Forty-five minutes of intestinal ischemia followed by 4 h of reperfusion caused an increase in intestinal levels of malondialdehyde in both nontransgenic and transgenic mice, but the concentration of malondialdehyde was significantly greater in nontransgenic mice. Intestinal ischemia-reperfusion also caused an increase in intestinal and pulmonary myeloperoxidase activity in nontransgenic and transgenic mice, but the transgenic mice had significantly lower levels of myeloperoxidase activity than nontransgenic mice. Transgenic mice had higher levels of intestinal SOD activity than nontransgenic mice. There were no significant differences in the catalase or glutathione peroxidase activities. In conclusion, our study demonstrates that the overexpression of SOD protects tissues from neutrophil infiltration and lipid peroxidation during intestinal ischemia-reperfusion.


Assuntos
Intestino Delgado/irrigação sanguínea , Isquemia/fisiopatologia , Traumatismo por Reperfusão/fisiopatologia , Superóxido Dismutase/metabolismo , Animais , Catalase/metabolismo , Glutationa Peroxidase/metabolismo , Heterozigoto , Humanos , Isquemia/enzimologia , Isquemia/mortalidade , Artéria Mesentérica Superior , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Camundongos Transgênicos , Traumatismo por Reperfusão/enzimologia , Superóxido Dismutase/genética
13.
EMBO J ; 16(23): 7105-17, 1997 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-9384588

RESUMO

Oct-1 and Oct-2 represent the prototypical example of related transcription factors with identical DNA recognition properties. They bind functionally critical octamer elements found in diverse regulatory sequences. It has not been possible to determine directly if these factors are functionally redundant or selective when interacting with different regulatory sequences in the appropriate cell type. An equivalent pair of altered DNA-binding specificity mutants of Oct-1 and Oct-2 are used to examine their function from varied regulatory contexts in B cells. These factors function as redundant activators of immunoglobulin (Ig) gene promoters (Vkappa and VH) and a histone H2B promoter. The structural basis of redundancy resides in the highly conserved DNA-binding POU domain, because this domain of either protein can activate transcription from both Ig and H2B promoters. We find that the nature of a distal enhancer dictates the relative potency of Oct-1 versus Oct-2 bound to a promoter. Oct-1 preferentially stimulates transcription from a VH or Vkappa promoter in combination with enhancers from the IgH or Igkappa locus, respectively. In this context, the more potent action of Oct-1 is dependent on a region external to the POU domain. These results suggest that Oct-1 may be the critical regulator of Ig gene transcription during B cell development and provide an explanation for selective Ig isotype expression defects in Oct-2 and OCA-B null mice.


Assuntos
Linfócitos B , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Genes de Imunoglobulinas , Fatores de Transcrição/metabolismo , Animais , Proteínas de Ligação a DNA/genética , Elementos Facilitadores Genéticos , Histonas/genética , Fator C1 de Célula Hospedeira , Cadeias Pesadas de Imunoglobulinas/genética , Região Variável de Imunoglobulina/genética , Cadeias kappa de Imunoglobulina/genética , Camundongos , Camundongos Mutantes , Mutação , Fator 1 de Transcrição de Octâmero , Fator 2 de Transcrição de Octâmero , Fatores do Domínio POU , Regiões Promotoras Genéticas , Ligação Proteica/genética , Transativadores/metabolismo , Fatores de Transcrição/genética , Transcrição Gênica
14.
Semin Pediatr Surg ; 5(3): 182-90, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8858765

RESUMO

The study of ligand receptor interactions and receptor function often requires multifaceted experimental approaches. In the course of studying the function and mechanism of action of müllerian inhibiting substance (MIS), we have used a wide range of molecular and cellular techniques. These have led to the identification, cloning, and characterization of the MIS receptors and of other receptors for the transforming growth factor-beta (TGF beta) family. This article describes the use of polymerase chain reaction (PCR) cloning to isolate candidate receptor genes, transfection and flow cytometry to study ligand binding, nonhomologous recombination targeted gene disruption (knockout) to analyze receptor function, and yeast genetics to identify other proteins that interact with the receptor complex. Together these techniques have led to the development of therapeutics and therapeutic strategies that are ready for clinical application.


Assuntos
Glicoproteínas , Receptores de Peptídeos/fisiologia , Receptores de Fatores de Crescimento Transformadores beta/fisiologia , Hormônio Antimülleriano , Técnicas Genéticas , Inibidores do Crescimento/isolamento & purificação , Inibidores do Crescimento/fisiologia , Humanos , Ductos Paramesonéfricos , Receptores de Peptídeos/análise , Receptores de Fatores de Crescimento Transformadores beta/análise , Hormônios Testiculares/isolamento & purificação , Hormônios Testiculares/fisiologia
15.
Cell ; 86(3): 435-44, 1996 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-8756725

RESUMO

The immunophilin FKBP12 is an evolutionarily conserved abundant protein; however, its physiological roles remain poorly defined. Here we report that FKBP12 is a common cytoplasmic interactor of TGF beta family type I receptors. FKBP12 binds to ligand-free TGF beta type I receptor, from which it is released upon a ligand-induced, type II receptor mediated phosphorylation of the type I receptor. Blocking FKBP12/type I receptor interaction with FK506 nonfunctional derivatives enhances the ligand activity, indicating that FKBP12 binding is inhibitory to the signaling pathways of the TGF beta family ligands. Overexpression of a myristylated FKBP12 in Mv1Lu cell specifically inhibits two separate pathways activated by TGF beta, and two point mutations on FKBP12 (G89P, I90K) abolish the inhibitory activity of FKBP12, suggesting that FKBP12 may dock a cytoplasmic protein to the type I receptors to inhibit TGF beta family mediated signaling.


Assuntos
Receptores de Ativinas Tipo I , Proteínas de Transporte/fisiologia , Proteínas de Ligação a DNA/fisiologia , Proteínas de Choque Térmico/fisiologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Receptores de Fatores de Crescimento Transformadores beta/antagonistas & inibidores , Fator de Crescimento Transformador beta/metabolismo , Sequência de Aminoácidos , Animais , Calcineurina , Proteínas de Ligação a Calmodulina/metabolismo , Drosophila , Dados de Sequência Molecular , Ácido Mirístico , Ácidos Mirísticos/metabolismo , Fosfoproteínas Fosfatases/metabolismo , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptor do Fator de Crescimento Transformador beta Tipo II , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Transdução de Sinais , Proteínas de Ligação a Tacrolimo , Transfecção
16.
Am J Med ; 101(1): 121-2; author reply 122, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8686709
17.
Science ; 271(5252): 1120-2, 1996 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-8599089

RESUMO

The alpha subunit of p21(RAS) farnesyltransferase (FNTA), which is also shared by geranylgeranyltransferase, was isolated as a specific cytoplasmic interactor of the transforming growth factor-beta (TGF-beta) and activin type I receptors with the use of the yeast two-hybrid system. FNTA interacts specifically with ligand-free TGF-beta type l receptor but is phosphorylated and released upon ligand binding. Furthermore, the release is dependent on the kinase activity of the TGF-beta type II receptor. Thus, the growth inhibitory and differentiative pathways activated by TGF-beta and activin involve novel mechanisms of serine-threonine receptor phosphorylation-dependent release of cytoplasmic interactors and regulation of the activation of small G proteins, such as p21(RAS).


Assuntos
Receptores de Ativinas Tipo I , Alquil e Aril Transferases , Inibinas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Transdução de Sinais , Transferases/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Receptores de Ativinas , Ativinas , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Humanos , Ligantes , Dados de Sequência Molecular , Mutação , Fosforilação , Proteínas Serina-Treonina Quinases/química , Proteínas Serina-Treonina Quinases/genética , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptor do Fator de Crescimento Transformador beta Tipo II , Receptores de Fatores de Crescimento/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/química , Receptores de Fatores de Crescimento Transformadores beta/genética , Proteínas Recombinantes de Fusão/metabolismo
18.
Endocrinology ; 137(1): 160-5, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8536608

RESUMO

We have isolated a candidate Müllerian inhibiting substance (MIS) type II receptor complementary DNA from an embryonic rat urogenital ridge library and have studied its binding to MIS, its developmental pattern of expression and tissue distribution. By in situ hybridization with a full-length riboprobe, the receptor is expressed in the mesenchymal cells surrounding the Müllerian duct at embryonic days 14, 15, and 16 and in tubular and follicular structures of the rat fetal gonads. Expression of the messenger RNA was also seen in the granules cells and seminiferous tubules of pubertal gonads. Northern analysis revealed that the MIS type II receptor messenger RNA is highly expressed in embryonic, pubertal, and adult testes and ovaries, as well as in the gravid uterus. The timing of expression in the gonads of both sexes was also analyzed by Northern analyses that showed high levels of expression at the time of Müllerian duct regression, much lower levels neonatally and prepubertally and then increased expression again with sexual maturation. The tissue and developmental specificity of expression of this receptor, which make it likely that this is the functional MIS type II receptor, can be used to advantage in therapeutic targeting strategies and to decipher the function of MIS in the gonads.


Assuntos
Envelhecimento/metabolismo , Animais Recém-Nascidos/metabolismo , Desenvolvimento Embrionário e Fetal , Feto/metabolismo , Receptores de Peptídeos/metabolismo , Sequência de Aminoácidos , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Sequência de Bases , Northern Blotting , Feminino , Hibridização In Situ , Masculino , Sondas Moleculares/genética , Dados de Sequência Molecular , Ratos/embriologia , Receptores de Peptídeos/genética , Receptores de Fatores de Crescimento Transformadores beta
19.
Leuk Res ; 19(12): 1001-4, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8632655

RESUMO

Patients with extreme leukocytosis or thrombocytosis who have hypoxemia on arterial blood gas analysis may demonstrate normal oxygen saturation using pulse oximetry. The most commonly invoked explanation for this phenomenon is oxygen consumption in the blood gas sample prior to analysis. However, others have challenged the premise that the hypoxemia is spurious. We describe a patient with extreme leukocytosis and hypoxemia in whom normoxia was confirmed by continuous blood gas analysis.


Assuntos
Gasometria , Hipóxia/diagnóstico , Leucemia Mielogênica Crônica BCR-ABL Positiva/complicações , Adulto , Gasometria/métodos , Feminino , Humanos , Hipóxia/sangue , Hipóxia/etiologia , Leucocitose/etiologia , Monitorização Fisiológica , Oxigênio/sangue
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