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1.
Hum Reprod ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38636947

RESUMO

STUDY QUESTION: Does BMI of gestational carriers (GCs) affect perinatal outcomes after embryo transfer? SUMMARY ANSWER: Overweight and class I obesity in GCs does not affect the rate of good perinatal outcomes. WHAT IS KNOWN ALREADY: The use of GCs is increasing, but uniform guidance regarding optimal BMI for GCs is lacking. Women with obesity who conceive without fertility treatment or through autologous or donor in vitro fertilization are at higher risk of adverse maternal and fetal outcomes, but data on obesity in GCs are very limited. STUDY DESIGN, SIZE, DURATION: We performed a retrospective cohort study of 1121 GC cycles from January 2015 to December 2020 at US Fertility, the largest national partnership of fertility practices in the USA. PARTICIPANTS/MATERIALS, SETTING, AND METHODS: All GC cycles performed at a large network of fertility practices were reviewed. Same-sex partners undergoing co-IVF were excluded. The primary outcome was good perinatal outcome from the first embryo transfer, defined as a singleton live birth at ≥37 weeks of gestation with birth weight between 2500 and 4000 g. Secondary outcome measures included frequencies of live birth, clinical pregnancy, miscarriage, full-term birth, low birth weight, large for gestational age, and cesarean delivery. A generalized linear model (log-binomial) was used for each to compare outcomes across BMI groups using normal BMI (20-24.9 kg/m2) as the reference group. Risk ratios and 95% CIs were estimated for each category group relative to normal BMI. MAIN RESULTS AND THE ROLE OF CHANCE: We identified 1121 cycles in which GCs underwent first embryo transfer, of which 263 (23.5%) were in GCs with BMI >30. Demographics and reproductive history for GCs did not differ by BMI groups. The age of intended parents, use of frozen eggs, and fresh embryo transfers were higher with increasing BMI group. There were no statistically significant associations between BMI and good perinatal outcomes, live birth, clinical pregnancy, biochemical, spontaneous abortion, or low birth weight. However, among live births, higher BMI was significantly associated with birth by cesarean (P = 0.015) and large for gestational age infants (P = 0.023). LIMITATIONS, REASONS FOR CAUTION: This was a retrospective study, and there may be unmeasured confounders. The number of patients with BMI <20 or ≥35 was small, limiting the power for these groups. We were not able to assess all maternal and fetal outcomes. WIDER IMPLICATIONS OF THE FINDINGS: In this study, we did not identify any significant impact of BMI on the chances of having a good perinatal outcome. Prior research studies have been inconsistent and this is the largest study to date. STUDY FUNDING/COMPETING INTEREST(S): No external funding was received for this work. The authors do not have any conflicts of interest to declare. TRIAL REGISTRATION NUMBER: N/A.

2.
Laryngorhinootologie ; 92(9): 589-93, 2013 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-23996551

RESUMO

OBJECTIVE: Peritonsillar abscess (PTA) is a common problem in otorhinolaryngology. The pathogenesis, supporting factors and optimal therapy are matter of numerous investigations. We studied retrospectively smoking habits, preoperative coagulation screening and the applied therapy of PTA. MATERIAL AND METHODS: Data from 460 patients who underwent treatment for PTA between 2000 and 2009 at Dessau Medical Center were retrospectively analysed. RESULTS: The highest incidence of PTA was found in young men, the prevalence of nicotine consumption was clearly increased in relation to the general population. The therapy of first choice was abscess tonsillectomy. Even with preoperative pathological coagulation-parameters no increased risk of secondary bleeding was shown. CONCLUSIONS: The part of smokers of patients with PTA is increased in comparison to the correspondent population of same age. A routine preoperative coagulation screening has a low benefit relating to the prediction of the risk of secondary bleeding. Abscess tonsillectomy is a safe method and has proved itself in clinical daily routine.


Assuntos
Testes de Coagulação Sanguínea , Programas de Rastreamento , Abscesso Peritonsilar/etiologia , Abscesso Peritonsilar/cirurgia , Hemorragia Pós-Operatória/prevenção & controle , Cuidados Pré-Operatórios , Fumar/efeitos adversos , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Estudos Transversais , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Abscesso Peritonsilar/diagnóstico por imagem , Abscesso Peritonsilar/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais , Fumar/epidemiologia , Tomografia Computadorizada por Raios X , Tonsilectomia , Adulto Jovem
3.
Cell Prolif ; 39(1): 15-28, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16426419

RESUMO

Recent research in cancer progression and treatment indicates that many forms of cancer arise from the development of a small subpopulation of abnormal cancer stem cells (CSCs) that promote cancer growth and spread. Many potential treatments preferentially interact with cells at certain stages of the cell cycle by either selective killing or halting the cell cycle, such as intense, nanosecond-duration pulsed electric fields (nsPEFs). Simple mathematical models of unfed cancer cell populations at the plateau of their growth characteristics may estimate the long-term consequences of these treatments on proliferating and quiescent cell populations. Applying such a model with no transition from the quiescent to proliferating state shows that it is possible for the proliferating cell population to fall below 1 if the quiescent cell population obtains a sufficient competitive advantage with respect to nutrient consumption and/or survival rate. Introducing small, realistic transition rates did not appreciably alter short-term or long-term population behaviour, indicating that the predicted small cell population behaviour (< 1 cell) is not an artefact of the simpler model. Experimental observations of nsPEF-induced effects on the cell cycle suggest that such a model may serve as a first step in assessing the viability of a given cancer treatment in vitro prior to clinical application.


Assuntos
Ciclo Celular , Modelos Biológicos , Neoplasias/patologia , Células-Tronco Neoplásicas/citologia , Animais , Divisão Celular , Linhagem Celular Tumoral , Sobrevivência Celular , Transformação Celular Neoplásica , Humanos
4.
Fertil Steril ; 76(5): 957-61, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11704117

RESUMO

OBJECTIVE: To assess the effect of ibuprofen, a nonspecific inhibitor of prostaglandin synthesis, on ovulation. DESIGN: Prospective, randomized, double-blind, placebo-controlled cross-over study. SETTING: University Medical Center. PATIENT(S): Twelve normally cycling women between ages 20 and 40. INTERVENTION(S): Subjects were randomized to either oral ibuprofen (800 mg) or placebo three times per day, beginning when the maximum diameter of the leading follicle reached 16 mm by ultrasound, and continuing for 10 days total. The second cycle was a washout period, and in the third cycle, the subjects were crossed over to the alternate regimen from the first cycle. The probability of delayed follicular collapse was determined using the binomial distribution, and changes in P levels were compared using the paired t test. MAIN OUTCOME MEASURE(S): Urinary LH surge, follicular collapse by serial transvaginal ultrasonography, and serum midluteal P levels. RESULT(S): Eleven of 12 subjects detected an LH surge with both ibuprofen and placebo. Five of 11 women demonstrated a >or=2-day increase in time interval from detection of the LH surge to follicular collapse, and 3 of those 5 had been randomized to ibuprofen. This represents a 27% (3 of 11; 95% confidence limits: 1%, 53%) rate of delay for follicular collapse for ibuprofen. There was no difference in average midluteal P levels for ibuprofen or placebo. CONCLUSION(S): If ibuprofen inhibits follicular collapse, this effect is seen in a small group of study subjects, and this information should be clinically reassuring to patients who take nonsteroidal anti-inflammatory drugs. Serum midluteal P levels were unaffected by administration of ibuprofen.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Ibuprofeno/farmacologia , Ovulação/efeitos dos fármacos , Adulto , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Folículo Ovariano/diagnóstico por imagem , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/fisiologia , Estudos Prospectivos , Fatores de Tempo , Ultrassonografia
5.
J Neurochem ; 76(4): 1177-87, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11181837

RESUMO

In mammals, cyclic GMP and cGMP-dependent protein kinases (cGKs) have been implicated in the regulation of many neuronal functions including long-term potentiation and long-term depression of synaptic efficacy. To develop Caenorhabditis elegans as a model system for studying the neuronal function of the cGKs, we cloned and characterized the cgk-1 gene. A combination of approaches showed that cgk-1 produces three transcripts, which differ in their first exon but are similar in length. Northern analysis of C. elegans RNA, performed with a probe designed to hybridize to all three transcripts, confirmed that a major 3.0 kb cgk-1 transcript is present at all stages of development. To determine if the CGK-1C protein was a cGMP-dependent protein kinase, CGK-1C was expressed in SF:9 cells and purified. CGK-1C shows a K(a) of 190 +/- 14 nM for cGMP and 18.4 +/- 2 microM for cAMP. Furthermore, CGK-1C undergoes autophosphorylation in a cGMP-dependent manner and is inhibited by the commonly used cGK inhibitor, KT5823. To determine which cells expressed CGK-1C, a 2.4-kb DNA fragment from the promoter of CGK-1C was used to drive GFP expression. The CGK-1C reporter construct is strongly expressed in the ventral nerve cord and in several other neurons as well as the marginal cells of the pharynx and intestine. Finally, RNA-mediated interference of CGK-1 resulted in movement defects in nematode larvae. These results provide the first demonstration that cGMP-dependent protein kinase is present in neurons of C. elegans and show that this kinase is required for normal motility.


Assuntos
Caenorhabditis elegans/enzimologia , Proteínas Quinases Dependentes de GMP Cíclico/genética , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Atividade Motora/fisiologia , Animais , DNA Complementar/genética , DNA Complementar/isolamento & purificação , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Fluorescência Verde , Isoenzimas/genética , Isoenzimas/metabolismo , Proteínas Luminescentes/biossíntese , Proteínas Luminescentes/genética , Microinjeções , Dados de Sequência Molecular , Atividade Motora/efeitos dos fármacos , Neurônios/citologia , Neurônios/metabolismo , Regiões Promotoras Genéticas/genética , RNA de Cadeia Dupla/administração & dosagem , RNA Mensageiro/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
6.
J Neurochem ; 76(4): 1252-63, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11181844

RESUMO

Nerve growth factor (NGF) has been shown to increase cyclic AMP in PC12 cells and to potentiate the actions of other agents that raise cyclic AMP. In our studies, NGF causes over 50% loss of PDE 2 activity (cyclic GMP-stimulated cyclic nucleotide phosphodiesterase) in PC12 cells within 24 h. After 72 h of NGF treatment, cyclic AMP hydrolysis in PC12 extracts is no longer cyclic GMP-stimulated. NGF deprivation increases the phosphodiesterase activity of treated cells. NGF does not decrease either PDE 2 mRNA or immunoreactivity of PDE 2A2 protein. Incubation of whole cells with micromolar Na(3)VO(4) mimics NGF treatment, reducing PDE 2 activity in PC12 cells by over 50% after 24 h, suggesting a phosphoprotein-mediated regulation of PDE 2 activity. Protein kinase inhibitor effects were difficult to assess due to their direct interaction with the PDE in cell lysates. To study phosphorylation in PDE 2 regulation, PDE 2A2 was epitope-tagged, and stable clonal PC12 cell transfectants were isolated (PC12B cells). When combined with metabolically labeled (32)P-phosphoproteins in vivo or in vitro, phosphoproteins of 108, 90, 64, 43, 33 and 19 kDa coprecipitated with epitope-tagged PDE 2A2 in an NGF sensitive manner. A 23-kDa phosphoprotein containing immunoreactive phosphoserine associated with the complex in an NGF independent manner. Phosphothreonine plus phosphotyrosine immunoreactivity at 23, 24, and 64 kDa as well as the phosphotyrosine immunoreactivity at 108, 90, 64, 43, 33, and 19 kDa required NGF or orthovanadate treatment. These proteins are hypothesized to be part of an NGF-regulated complex controlling PDE 2A2 activity.


Assuntos
Fator de Crescimento Neural/metabolismo , Células PC12/metabolismo , Fosfoproteínas/metabolismo , Diester Fosfórico Hidrolases/metabolismo , Animais , Autorradiografia , AMP Cíclico/metabolismo , GMP Cíclico/metabolismo , GMP Cíclico/farmacologia , Nucleotídeo Cíclico Fosfodiesterase do Tipo 2 , Relação Dose-Resposta a Droga , Eletroforese em Gel de Poliacrilamida , Inibidores Enzimáticos/farmacologia , Fator de Crescimento Neural/farmacologia , Neuritos/efeitos dos fármacos , Neuritos/metabolismo , Células PC12/citologia , Células PC12/efeitos dos fármacos , Inibidores de Fosfodiesterase/farmacologia , Diester Fosfórico Hidrolases/efeitos dos fármacos , Diester Fosfórico Hidrolases/genética , Radioisótopos de Fósforo , Proteínas Tirosina Fosfatases/antagonistas & inibidores , RNA Mensageiro/metabolismo , Ratos , Proteínas Recombinantes/efeitos dos fármacos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Fatores de Tempo
7.
Hum Reprod ; 16(1): 174-176, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11139559

RESUMO

Ovarian hyperstimulation syndrome (OHSS) remains the most serious medical complication of controlled ovarian stimulation. An unusual case of perforated duodenal ulcer following critical OHSS is presented. A 29 year old nulligravid woman with polycystic ovarian syndrome underwent her first attempt at in-vitro fertilization. She was admitted to the hospital with critical OHSS and subsequently found to have a perforated posterior duodenal ulcer. She underwent exploratory laparotomy, antrectomy and gastrojejunostomy. Pathological analysis of her gastric antrum confirmed chronic gastritis and Helicobacter pylori. She required prolonged assisted ventilation, vasopressor support, multiple i.v. antibiotics, blood product replacement and nutritional support. The patient was hospitalized for a total of 47 days and then transferred to a rehabilitation facility for an additional 30 days before being discharged to home. In this critically ill patient with OHSS, severe stress associated with invasive monitoring and multiple medical therapies in the intensive care unit as well as H. pylori infection appear to be the most probable causative factors of her perforated viscus. Prompt recognition of potential complications and proper medical intervention are essential in the management of patients with OHSS. Avoidance strategies are still needed.


Assuntos
Úlcera Duodenal/etiologia , Perfuração Intestinal/etiologia , Síndrome de Hiperestimulação Ovariana/complicações , Adulto , Estado Terminal , Feminino , Fertilização in vitro/efeitos adversos , Gastrite/complicações , Infecções por Helicobacter/complicações , Helicobacter pylori , Humanos , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/terapia
8.
Invest Ophthalmol Vis Sci ; 41(9): 2766-73, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10937596

RESUMO

PURPOSE: To examine the expression of the major isoforms of cyclic guanosine monophosphate (cGMP)-dependent protein kinase (cGK) in mouse eye. METHODS: Immunohistochemical localization of cGMP in mouse eye cryosections was performed using an anti-cGMP antibody, followed by visualization with indirect fluorescence microscopy. The presence of types Ialpha, Ibeta, and II cGK mRNAs in mouse eye extracts was determined initially by RNase protection analysis. Further localization of cGK I and II mRNAs on cryosections was accomplished by in situ hybridization using digoxigenin-labeled cRNA probes and an alkaline phosphatase-conjugated anti-digoxigenin antibody. Finally, cGK I protein was localized to subcellular areas within the retina using an anti-cGK I-specific primary antibody. RESULTS: In initial immunohistochemical experiments cGMP was present in numerous regions and layers within the eye and retina. Subsequent RNase protection studies demonstrated that cGK Ialpha, Ibeta, and II mRNAs were present in mouse eye and that type Ibeta mRNA were 6.6 and 30 times more abundant than type Ialpha and type II, respectively. By in situ hybridization, cGK I mRNA was localized to photoreceptor inner segments and the ganglion cell and inner nuclear layers of the retina, and lesser amounts were found in the ciliary epithelium, lens, and cornea. The cGK II mRNA expression pattern was similar but not identical with that of cGK I. Finally, within the retina, cGK I protein was most abundant in the inner plexiform layer, with significant amounts in ganglion cells and photoreceptor inner segments as well. CONCLUSIONS: The presence of these cGK isoforms in discrete areas throughout the eye suggests multiple roles for the cGMP-dependent signal transduction system in the regulation of physiologic and pathologic ocular processes.


Assuntos
Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Olho/enzimologia , Animais , Western Blotting , Proteínas Quinases Dependentes de GMP Cíclico/genética , Técnica Indireta de Fluorescência para Anticorpo , Hibridização In Situ , Isoenzimas/genética , Isoenzimas/metabolismo , Camundongos , Microscopia de Fluorescência , Plasmídeos , RNA Mensageiro/metabolismo
9.
J Biol Chem ; 275(36): 28053-62, 2000 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-10864932

RESUMO

For the type I cGMP-dependent protein kinases (cGKIalpha and cGKIbeta), a high affinity interaction exists between the C2 amino group of cGMP and the hydroxyl side chain of a threonine conserved in most cGMP binding sites. To examine the effect of this interaction on ligand binding and kinase activation in the type II isozyme of cGMP-dependent protein kinase (cGKII), alanine was substituted for the conserved threonine or serine. cGKII was found to require the C2 amino group of cGMP and its cognate serine or threonine hydroxyl for efficient cGMP activation. Of the two binding sites, disruption of cGMP-specific binding in the NH(2)-terminal binding site had the greatest effect on cGMP-dependent kinase activation, like cGKI. However, ligand dissociation studies showed that the location of the rapid and slow dissociation sites of cGKII was reversed relative to cGKI. Another set of mutations that prevented cyclic nucleotide binding demonstrated the necessity of the NH(2)-terminal, rapid dissociation binding site for cyclic nucleotide-dependent activation of cGKII. These findings suggest distinct mechanisms of activation for cGKII and cGKI isoforms. Because cGKII mediates the effects of heat-stable enterotoxins via the cystic fibrosis transmembrane regulator Cl(-) channel, these findings define a structural target for drug design.


Assuntos
Proteínas Quinases Dependentes de GMP Cíclico/química , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Sequência de Aminoácidos , Substituição de Aminoácidos , Animais , Sítios de Ligação , Linhagem Celular , Sequência Conservada , AMP Cíclico/metabolismo , Proteína Quinase Dependente de GMP Cíclico Tipo II , Ativação Enzimática , Isoenzimas/química , Isoenzimas/metabolismo , Cinética , Modelos Moleculares , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Conformação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Serina , Spodoptera , Treonina
10.
Menopause ; 7(3): 162-7, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10810961

RESUMO

OBJECTIVE: To examine the role of estrogen replacement therapy on the development of gallbladder disease in postmenopausal women. DESIGN: Systematic review of the English literature was conducted. All studies that addressed the association between hormone replacement therapy and gallbladder disease published from 1970 to the present were reviewed. RESULTS: Seven observational studies, two clinical trials, two case series, and one nonrandomized and three randomized investigations were reviewed. The results of each study were reported and analyzed. CONCLUSIONS: Estrogen replacement therapy in postmenopausal women increased the chances for gallstone formation.


Assuntos
Terapia de Reposição de Estrogênios/efeitos adversos , Doenças da Vesícula Biliar/etiologia , Pós-Menopausa , Bile/efeitos dos fármacos , Colelitíase/química , Colelitíase/etiologia , Colesterol/análise , Feminino , Humanos , Fatores de Risco
11.
J Biol Chem ; 275(32): 24333-40, 2000 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-10811639

RESUMO

Chain elongation of fatty acids is an important cellular process and is believed to occur in the endoplasmic reticulum of all eukaroytic cells. Herein we describe the cloning and characterization of a peroxisomal NADPH-specific trans-2-enoyl-CoA reductase, the key enzyme for a proposed peroxisomal chain elongation pathway. The reductase was solubilized and partially purified from guinea pig liver peroxisomes by affinity chromatography. On SDS-polyacrylamide gel electrophoresis, a 40-kDa band was identified as the enzyme, and its partial amino acid sequence (27 amino acids) was determined. A full-length cDNA for the reductase was cloned from a guinea pig liver cDNA library. The open reading frame of this nucleotide sequence encodes a 302-amino acid polypeptide with a calculated molecular mass of 32.5 kDa. Full-length mouse and human cDNA clones encoding homologous proteins have also been isolated. All of these translated polypeptides have the type I peroxisomal targeting signal, AKL, at the carboxyl terminus. The identity of the cloned enoyl-CoA reductase cDNAs was confirmed by expressing the guinea pig and human cDNAs in Escherichia coli. The His-tagged recombinant enzymes were found to have very high NADPH-specific 2-enoyl-CoA reductase activity with similar properties and specificity as the liver peroxisomal reductase. Both the natural and the recombinant enzyme catalyze the reduction of trans-2-enoyl-CoAs of varying chain lengths from 6:1 to 16:1, having maximum activity with 10:1 CoA. Northern blot analysis demonstrated that a single transcript of 1.3 kilobases is present in most mouse tissues, with particularly high concentrations in liver and kidney.


Assuntos
Ácidos Graxos Dessaturases/genética , Ácidos Graxos Dessaturases/metabolismo , Ácido Graxo Sintases , Fígado/enzimologia , NADH NADPH Oxirredutases , Peroxissomos/enzimologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Cromatografia de Afinidade , Clonagem Molecular , Ácidos Graxos Dessaturases/química , Cobaias , Humanos , Cinética , Mamíferos , Camundongos , Microssomos Hepáticos/enzimologia , Dados de Sequência Molecular , Ratos , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Especificidade por Substrato
12.
Mol Cell Biol ; 20(10): 3442-8, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10779334

RESUMO

Protein kinase inhibitor (PKI) is a potent endogenous inhibitor of the cyclic AMP (cAMP)-dependent protein kinase (PKA). It functions by binding the free catalytic (C) subunit with a high affinity and is also known to export nuclear C subunit to the cytoplasm. The significance of these actions with respect to PKI's physiological role is not well understood. To address this, we have generated by homologous recombination mutant mice that are deficient in PKIalpha, one of the three isoforms of PKI. The mice completely lack PKI activity in skeletal muscle and, surprisingly, show decreased basal and isoproterenol-induced gene expression in muscle. Further examination revealed reduced levels of the phosphorylated (active) form of the transcription factor CREB (cAMP response element binding protein) in the knockouts. This phenomenon stems, at least in part, from lower basal PKA activity levels in the mutants, arising from a compensatory increase in the level of the RIalpha subunit of PKA. The deficit in gene induction, however, is not easily explained by current models of PKI function and suggests that PKI may play an as yet undescribed role in PKA signaling.


Assuntos
Proteínas de Transporte/genética , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Peptídeos e Proteínas de Sinalização Intracelular , Músculo Esquelético/fisiologia , Animais , AMP Cíclico/farmacologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Inibidores Enzimáticos , Regulação da Expressão Gênica , Homozigoto , Isoproterenol/farmacologia , Camundongos , Camundongos Knockout , Fosforilação , Isoformas de Proteínas/genética , Transdução de Sinais , Ativação Transcricional
13.
Biochem J ; 345 Pt 3: 673-80, 2000 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-10642527

RESUMO

Peutz-Jeghers syndrome (PJS) is an autosomal dominant disease characterized by melanocytic macules, hamartomatous polyps and an increased risk for numerous cancers. The human LKB1 (hLKB1) gene encodes a serine/threonine protein kinase that is deficient in the majority of patients with PJS. The murine LKB1 (mLKB1) cDNA was isolated, sequenced and shown to produce a 2.4-kb transcript encoding a 436 amino acid protein with 90% identity with hLKB1. RNA blot and RNase-protection analysis revealed that mLKB1 mRNA is expressed in all tissues and cell lines examined. The widespread expression of LKB1 transcripts is consistent with the elevated risk of multiple cancer types in PJS patients. The predicted LKB1 protein sequence terminates with a conserved prenylation motif (Cys(433)-Lys-Gln-Gln(436)) directly downstream from a consensus cAMP-dependent protein kinase (PKA) phosphorylation site (Arg(428)-Arg-Leu-Ser(431)). The expression of enhanced green fluorescent protein (EGFP)-mLKB1 chimaeras demonstrated that LKB1 possesses a functional prenylation motif that is capable of targeting EGFP to cellular membranes. Mutation of Cys(433) to an alanine residue, but not phosphorylation by PKA, blocked membrane localization. These findings suggest that PKA does phosphorylate LKB1, although this phosphorylation does not alter the cellular localization of LKB1.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Quinases Proteína-Quinases Ativadas por AMP , Proteínas Quinases Ativadas por AMP , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Clonagem Molecular , Regulação da Expressão Gênica no Desenvolvimento , Genes Supressores de Tumor , Proteínas de Fluorescência Verde , Humanos , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Camundongos , Dados de Sequência Molecular , Síndrome de Peutz-Jeghers/genética , Síndrome de Peutz-Jeghers/metabolismo , Fosforilação , Prenilação de Proteína , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Análise de Sequência , Homologia de Sequência de Aminoácidos , Células Tumorais Cultivadas
14.
J Assist Reprod Genet ; 16(8): 402-4, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10478317

RESUMO

OBJECTIVE: Our objective was to assess the clinical outcome of tubal reversal in women of advanced reproductive age. METHODS: A multicenter retrospective chart review of 153 patients who underwent a tubal ligation reversal was carried out. Patients were evaluated according to age. All patients had documented ovulation and a partner with a normal semen analysis by WHO criteria. Outcome measures included rates of clinical pregnancy, ectopic pregnancy, spontaneous abortion, and live birth, and the time to conception. RESULTS: Clinical pregnancy rates were significantly lower in women > or = 40 compared to younger groups. The time to conception was significantly shorter for women < 30 compared to women > or = 35. No pregnancies occurred in women > or = 42. CONCLUSIONS: Our data support the judicious use of sterilization reversal for infertile women with no male factor through their early forties. Women > or = 42 years should be especially counseled as to the very low success rates.


Assuntos
Reversão da Esterilização , Esterilização Tubária , Adulto , Fatores Etários , Feminino , Humanos , Masculino , Gravidez , Resultado da Gravidez , Taxa de Gravidez , Gravidez Ectópica , Estudos Retrospectivos
15.
J Biol Chem ; 274(13): 8391-404, 1999 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-10085070

RESUMO

The ability of cGMP-dependent protein kinases (cGKs) to activate cAMP response element (CRE)-dependent gene transcription was compared with that of cAMP-dependent protein kinases (cAKs). Although both the type Ibeta cGMP-dependent protein kinase (cGKIbeta) and the type II cAMP-dependent protein kinase (cAKII) phosphorylated the cytoplasmic substrate VASP (vasodilator- and A kinase-stimulated phosphoprotein) to a similar extent, cyclic nucleotide regulation of CRE-dependent transcription was at least 10-fold higher in cAKII-transfected cells than in cGKIbeta-transfected cells. Overexpression of each kinase in mammalian cells resulted in a cytoplasmic localization of the unactivated enzyme. As reported previously, the catalytic (C) subunit of cAKII translocated to the nucleus following activation by 8-bromo-cyclic AMP. However, cGKIbeta did not translocate to the nucleus upon activation by 8-bromo-cyclic GMP. Replacement of an autophosphorylated serine (Ser79) of cGKIbeta with an aspartic acid resulted in a mutant kinase with constitutive kinase activity in vitro and in vivo. The cGKIbetaS79D mutant localized to the cytoplasm and was only a weak activator of CRE-dependent gene transcription. However, an amino-terminal deletion mutant of cGKIbeta was found in the nucleus as well as the cytoplasm and was a strong activator of CRE-dependent gene transcription. These data suggest that the inability of cGKs to translocate to the nucleus is responsible for the differential ability of cAKs and cGKs to activate CRE-dependent gene transcription and that nuclear redistribution of cGKs is not required for NO/cGMP regulation of gene transcription.


Assuntos
Proteínas de Transporte/genética , Proteínas Quinases Dependentes de AMP Cíclico/genética , Proteínas Quinases Dependentes de GMP Cíclico/genética , Peptídeos e Proteínas de Sinalização Intracelular , Sequência de Aminoácidos , Animais , Sequência de Bases , Encéfalo/metabolismo , Moléculas de Adesão Celular/metabolismo , Linhagem Celular , Clonagem Molecular , AMP Cíclico/análogos & derivados , AMP Cíclico/farmacologia , Proteína Quinase Tipo II Dependente de AMP Cíclico , GMP Cíclico/análogos & derivados , GMP Cíclico/farmacologia , Imunofluorescência , Genes Reporter/genética , Camundongos , Proteínas dos Microfilamentos , Dados de Sequência Molecular , Mutação/genética , Fosfoproteínas/metabolismo , Fosforilação , Ativação Transcricional/genética , Transfecção/genética
16.
J Neurochem ; 72(4): 1362-71, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10098837

RESUMO

We previously reported cloning of cDNAs encoding both components of a protein doublet induced during goldfish optic nerve regeneration. The predicted protein sequences showed significant homology with the mammalian 2',3'-cyclic-nucleotide 3'-phosphodiesterases (CNPases). CNPases are well-established markers of mammalian myelin; hence, the cDNAs were designated gRICH68 and gRICH70 (for goldfish Regeneration-Induced CNPase Homologues of 68 and 70 kDa). Homologous cDNAs have now been isolated from zebrafish encoding a highly related protein, which we have termed zRICH. RNase protection assays show that zRICH mRNA is induced significantly (fivefold) in optic nerve regenerating zebrafish retinas 7 days following nerve crush. Western blots show a single band in zebrafish brain and retina extracts, with immunoreactivity increasing three-fold in regenerating retinas 21 days postcrush. Immunohistochemical analysis indicated that this increase in zRICH protein expression is localized to the retinal ganglion cell layer in regenerating retina. We have characterized and evaluated the relevance of a conserved beta-ketoacyl synthase motif in zRICH to CNPase activity by means of site-directed mutagenesis. Two residues within the motif, H334 and T336, are critical for enzymatic activity. A cysteine residue within the motif, which corresponds to a critical residue for beta-ketoacyl synthase, does not appear to participate in the phosphodiesterase activity.


Assuntos
2',3'-Nucleotídeo Cíclico Fosfodiesterases/genética , Proteínas de Peixes , Regeneração Nervosa/fisiologia , Nervo Óptico/enzimologia , 2',3'-Nucleotídeo Cíclico Fosfodiesterases/química , 3-Oxoacil-(Proteína de Transporte de Acila) Sintase/genética , Acetil-CoA C-Aciltransferase/genética , Animais , Sequência de Bases , Sítios de Ligação/genética , Clonagem Molecular , Sequência Conservada , Expressão Gênica/fisiologia , Isoenzimas/genética , Cinética , Dados de Sequência Molecular , Mutagênese/fisiologia , Proteínas do Tecido Nervoso/genética , Nervo Óptico/citologia , Estrutura Terciária de Proteína , RNA Mensageiro/análise , Células Ganglionares da Retina/química , Células Ganglionares da Retina/enzimologia , Homologia de Sequência de Aminoácidos , Especificidade da Espécie , Peixe-Zebra
17.
J Biol Chem ; 274(6): 3485-95, 1999 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-9920894

RESUMO

G-substrate, a specific substrate of the cGMP-dependent protein kinase, has previously been localized to the Purkinje cells of the cerebellum. We report here the isolation from mouse brain of a cDNA encoding G-substrate. This cDNA was used to localize G-substrate mRNA expression, as well as to produce recombinant protein for the characterization of G-substrate phosphatase inhibitory activity. Brain and eye were the only tissues in which a G-substrate transcript was detected. Within the brain, G-substrate transcripts were restricted almost entirely to the Purkinje cells of the cerebellum, although transcripts were also detected at low levels in the paraventricular region of the hypothalamus and the pons/medulla. Like the native protein, the recombinant protein was preferentially phosphorylated by cGMP-dependent protein kinase (Km = 0.2 microM) over cAMP-dependent protein kinase (Km = 2.0 microM). Phospho-G-substrate inhibited the catalytic subunit of native protein phosphatase-1 with an IC50 of 131 +/- 27 nM. Dephospho-G-substrate was not found to be inhibitory. Both dephospho- and phospho-G-substrate were weak inhibitors of native protein phosphatase-2A1, which dephosphorylated G-substrate 20 times faster than the catalytic subunit of protein phosphatase-1. G-substrate potentiated the action of cAMP-dependent protein kinase on a cAMP-regulated luciferase reporter construct, consistent with an inhibition of cellular phosphatases in vivo. These results provide the first demonstration that G-substrate inhibits protein phosphatase-1 and suggest a novel mechanism by which cGMP-dependent protein kinase I can regulate the activity of the type 1 protein phosphatases.


Assuntos
Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Fosfoproteínas Fosfatases/antagonistas & inibidores , Células de Purkinje/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Clonagem Molecular , Primers do DNA , DNA Complementar , Humanos , Cinética , Camundongos , Dados de Sequência Molecular , Proteínas do Tecido Nervoso/genética , Fosforilação , Proteína Fosfatase 1 , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos , Especificidade por Substrato
18.
J Clin Endocrinol Metab ; 83(2): 410-4, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9467549

RESUMO

This prospective, randomized, double blind, parallel study was undertaken to elucidate further the potential mechanisms through which estrogens could promote the formation of cholesterol gallstones and to compare the impact of nonoral (transdermal) and oral estrogens on serum, hepatic, and biliary markers of estrogen action. Ninety-seven postmenopausal women were randomized to receive either transdermal estradiol (E2; 0.1 mg every 3.5 days; n = 48) or oral conjugated equine estrogens (1.25 mg every day; n = 49) for 8 weeks. Blood samples were drawn, and bile samples were obtained by cholecystokinin-stimulated duodenal drainage before and after 8 weeks of estrogen administration. The main outcome measures included serum FSH, LH, E2, estrone, estrone sulfate, sex hormone-binding globulin, lipid profiles, biliary cholesterol saturation index, cholesterol nucleation time, presence of cholesterol crystals in bile, as well as biliary arachidonate, PGE2, and mucous glycoproteins. Estrogens administered by both routes increased circulating estrogens and resulted in similar suppression of both gonadotropins. Sex hormone-binding globulin was clearly increased, and the changes in serum lipids were more pronounced with oral conjugated equine estrogens than with transdermal E2. The biliary cholesterol saturation index was significantly increased compared to the baseline values with both transdermal E2 (1.08 +/- 0.04 vs. 1.00 +/- 0.03; mean change, 8%) and oral conjugated equine estrogens (1.04 +/- 0.03 vs. 0.99 +/- 0.03; mean change, 6%); however, there was no difference between the treatments. The number of patients with cholesterol crystals detected in bile was similar after both estrogen regimens. Transdermal and oral estrogens decreased nucleation time in vitro, increased arachidonate and PGE2 levels, and minimally raised total glycoprotein concentrations. In conclusion, transdermal and oral estrogens exerted comparable nonhepatic effects, as evidenced by similar reductions of gonadotropin levels, but oral therapy exhibited substantially greater actions on hepatic markers of estrogen action. Both transdermal E2 and oral conjugated equine estrogens significantly elevated the biliary cholesterol saturation index and reduced the nucleation time. These results suggest that estrogens at the doses studied could promote gallstone formation by alteration of biliary lipids and cholesterol nucleation time that have been incriminated in this process.


Assuntos
Biomarcadores , Colelitíase/induzido quimicamente , Estrogênios/administração & dosagem , Estrogênios/efeitos adversos , Pós-Menopausa , Administração Cutânea , Adulto , Idoso , Animais , Bile/metabolismo , Colesterol/metabolismo , Cristalização , Método Duplo-Cego , Feminino , Cavalos , Humanos , Lipídeos/sangue , Pessoa de Meia-Idade , Estudos Prospectivos
19.
J Biol Chem ; 272(29): 18169-78, 1997 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-9218452

RESUMO

Attempts to understand the physiological roles of the protein kinase inhibitor (PKI) proteins have been hampered by a lack of knowledge concerning the molecular heterogeneity of the PKI family. The PKIgamma cDNA sequence determined here predicted an open reading frame of 75 amino acids, showing 35% identity to PKIalpha and 30% identity to PKIbeta1. Residues important for the high affinity of PKIalpha and PKIbeta1 as well as nuclear export of the catalytic (C) subunit of cAMP-dependent protein kinase were found to be conserved in PKIgamma. Northern blot analysis showed that a 1.3-kilobase PKIgamma message is widely expressed, with highest levels in heart, skeletal muscle, and testis. RNase protection analysis revealed that in most tissues examined PKIgamma is expressed at levels equal to or higher than the other known PKI isoforms and that in several mouse-derived cell lines, PKIgamma is the predominant PKI message. Partial purification of PKI activities from mouse heart by DEAE ion exchange chromatography resolved two major inhibitory peaks, and isoform-specific polyclonal antibodies raised against recombinant PKIalpha and PKIgamma identified these inhibitory activities to be PKIalpha and PKIgamma. A comparison of inhibitory potencies of PKIalpha and PKIgamma expressed in Escherichia coli revealed that PKIgamma was a potent competitive inhibitor of Calpha phosphotransferase activity in vitro (Ki = 0.44 nM) but is 6-fold less potent than PKIalpha (Ki = 0.073 nM). Like PKIalpha, PKIgamma was capable of blocking the nuclear accumulation of Flag-tagged C subunit in transiently transfected mammalian cells. Finally, the murine PKIgamma gene was found to overlap the murine adenosine deaminase gene on mouse chromosome 2. These results demonstrate that PKIgamma is a novel, functional PKI isoform that accounts for the previously observed discrepancy between PKI activity and PKI mRNA levels in several mammalian tissues.


Assuntos
Proteínas de Transporte/biossíntese , Proteínas de Transporte/química , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Inibidores Enzimáticos/química , Peptídeos e Proteínas de Sinalização Intracelular , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas de Transporte/farmacologia , Linhagem Celular , Cromatografia DEAE-Celulose , Primers do DNA , Humanos , Cinética , Camundongos , Dados de Sequência Molecular , Miocárdio/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacologia , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Transfecção
20.
J Pediatr Adolesc Gynecol ; 10(2): 73-7, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9179805

RESUMO

Tuboovarian abscess is a serious consequence of pelvic inflammatory disease, especially in the adolescent population. Early diagnosis and treatment are essential to prevent further sequelae including infertility, ectopic pregnancy, and chronic pelvic pain. Not all patients, however, present with pelvic pain, pelvic mass, fever, and leukocytosis. We present the case of a sexually active 15-year-old black girl who presented with mild abdominal pain and excessive vaginal bleeding without pelvic mass, fever, or leukocytosis. Erythrocyte sedimentation rate was 66 mm/h. Pelvic ultrasound revealed bilateral complex ovarian masses. At laparoscopy, the patient had bilateral tuboovarian abscesses with extensive adhesions to the pelvic side walls. This case illustrates the need for a high index of suspicion of tuboovarian abscess in sexually active adolescents.


Assuntos
Abscesso/diagnóstico , Doenças dos Anexos/diagnóstico , Comportamento Sexual , Abscesso/complicações , Doenças dos Anexos/complicações , Adolescente , Diagnóstico Diferencial , Feminino , Humanos
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