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1.
Catheter Cardiovasc Interv ; 88(5): 740-747, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26833916

RESUMO

OBJECTIVES: This study sought to assess the impact of residual coronary artery disease (CAD), using the residual SYNTAX score (rSS), on in-hospital outcomes after primary percutaneous intervention (PPCI). The study also aimed to determine independent predictors for high rSS. Residual CAD has been associated with worsened prognosis in patients undergoing PCI for non-ST acute coronary syndromes. The rSS is a systematic angiographic score that measures the extent and complexity of residual CAD after PCI. MATERIALS AND METHODS: Data from 243 consecutive patients undergoing PPCI for ST-elevation myocardial infarction (STEMI) were analyzed. The rSS was derived from post-PPCI angiography. Patients were dichotomized into low (<8) and high rSS (≥8) groups and outcomes were compared between groups. The primary outcome of net adverse cardiovascular events (NACE) consisted of a composite of in-hospital death, congestive heart failure (CHF), recurrent MI and bleeding. RESULTS: The mean rSS was 4.7 (±7.2). A high rSS was associated with the primary outcome (P < 0.0001), in-hospital death (P = 0.0026), periprocedural death (P < 0.0001), CHF (P < 0.0004) and acute kidney injury (P < 0.0019). A high rSS was also an independent predictor of the primary outcome with an OR of 3.82. Independent predictors of a high rSS included a history of diabetes (OR 2.8), previous MI (OR 5.75), 2-vessel disease (VD) (OR 15.48, vs. 1-VD) and 3-VD (OR 57.06, vs. 1-VD). CONCLUSIONS: Residual CAD, as assessed by the rSS, confers a worsened prognosis in patients undergoing PPCI. Diabetes, previous MI and multi-vessel disease were independent predictors of a high rSS. © 2016 Wiley Periodicals, Inc.


Assuntos
Intervenção Coronária Percutânea/métodos , Complicações Pós-Operatórias/epidemiologia , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia , Idoso , Angiografia Coronária , Feminino , Seguimentos , Mortalidade Hospitalar/tendências , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Quebeque/epidemiologia , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Fatores de Tempo
2.
Climacteric ; 18(6): 817-25, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26517756

RESUMO

OBJECTIVE: The aim was to analyze the opinion of the male partner of women treated for vulvovaginal atrophy (VVA) with intravaginal 0.50% DHEA (prasterone), thus providing information on both members of the couple. METHODS: On a voluntary basis, in a prospective, randomized, double-blind and placebo-controlled phase-III clinical trial, the male partner filled a questionnaire at baseline and at 12 weeks stating his observations related to his penis and intercourse before and after VVA treatment. RESULTS: Sixty-six men having a partner treated with intravaginal DHEA and 34 others having a partner treated with placebo answered the questionnaires. Concerning the feeling of vaginal dryness of their female partner, the severity score following DHEA treatment improved by 81% (0.76 units) over placebo (p = 0.0347). Thirty-six percent of men having a partner treated with DHEA did not feel the vaginal dryness of the partner at the end of treatment compared to 7.8% in the placebo group. When analyzing the situation at 12 weeks compared to baseline, an improved score of 1.09 units was the difference found for the DHEA group compared to 0.76 for the placebo group (p = 0.05 vs. placebo). In the DHEA group, 38% of men scored very improved compared to 18% in the placebo group. No adverse event has been reported. CONCLUSION: The male partner had a very positive evaluation of the treatment received by his female partner.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Desidroepiandrosterona/administração & dosagem , Doenças do Pênis/etiologia , Parceiros Sexuais , Vagina/patologia , Vulva/patologia , Administração Intravaginal , Adulto , Idoso , Idoso de 80 Anos ou mais , Atrofia/complicações , Atrofia/tratamento farmacológico , Coito , Método Duplo-Cego , Dispareunia/etiologia , Eritema/etiologia , Feminino , Fricção/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensação/efeitos dos fármacos , Índice de Gravidade de Doença , Inquéritos e Questionários , Resultado do Tratamento , Vagina/efeitos dos fármacos , Vulva/efeitos dos fármacos
3.
Climacteric ; 18(4): 590-607, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25511551

RESUMO

OBJECTIVE: While daily intravaginal administration of 0.50% (6.5 mg) dehydroepiandrosterone (DHEA, prasterone) for 12 weeks has shown clinically and statistically significant effects on moderate to severe (MS) dyspareunia as the most bothersome symptom (MBS), the present study analyzes the effect of a reduced dosing regimen on MBS vaginal dryness. METHOD: Daily intravaginal 0.50% prasterone for 2 weeks followed by twice weekly for 10 weeks versus placebo. RESULTS: Maximal beneficial changes in vaginal parabasal and superficial cells and pH were observed at 2 weeks as observed for intravaginal 10 µg estradiol (E2). This was followed by a decrease or lack of efficacy improvement after switching to twice-weekly dosing. The decrease in percentage of parabasal cells, increase in percentage of superficial cells and decrease in vaginal pH were all highly significant (p < 0.0001 to 0.0002 over placebo) at 12 weeks. In parallel, the statistical significance over placebo (p value) on MBS vaginal dryness at 6 weeks was 0.09 followed by an increase to 0.198 at 12 weeks. For MBS dyspareunia, the p value of 0.008 at 6 weeks was followed by a p value of 0.077 at 12 weeks, thus illustrating a decrease of efficacy at the lower dosing regimen. The improvements of vaginal secretions, color, epithelial integrity and epithelial surface thickness were observed at a p value < 0.01 or 0.05 over placebo at 2 weeks, with a similar or loss of statistical difference compared to placebo at later time intervals. No significant adverse event was observed. Vaginal discharge related to the melting of Witepsol was reported in 1.8% of subjects. CONCLUSION: The present data show that daily dosing with 0.50% DHEA for 2 weeks followed by twice-weekly dosing is a suboptimal treatment of the symptoms/signs of vulvovaginal atrophy resulting from a substantial loss of the efficacy achieved at daily dosing.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Desidroepiandrosterona/administração & dosagem , Doenças Vaginais/tratamento farmacológico , Doenças da Vulva/tratamento farmacológico , Adjuvantes Imunológicos/uso terapêutico , Administração Intravaginal , Adulto , Idoso , Atrofia/complicações , Atrofia/tratamento farmacológico , Desidroepiandrosterona/uso terapêutico , Método Duplo-Cego , Esquema de Medicação , Dispareunia/tratamento farmacológico , Dispareunia/etiologia , Feminino , Humanos , Pessoa de Meia-Idade , Pós-Menopausa , Resultado do Tratamento , Doenças Vaginais/complicações , Doenças da Vulva/complicações
5.
Transfus Med ; 23(1): 55-60, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23167310

RESUMO

OBJECTIVE: The objective of this study is to evaluate the economic benefits of immunoglobulin replacement therapy achieved subcutaneously (subcutaneous immunoglobulin, SCIG) by the rapid push method compared to intravenous infusion therapy (intravenous immunoglobulin, IVIG) in primary immune deficiency (PID) patients from the healthcare system perspective in the context of the adult SCIG home infusion program based at St Paul's Hospital, Vancouver, Canada. MATERIALS AND METHODS: SCIG and IVIG options were compared in cost-minimisation and budget impact models (BIMs) over 3 years. Sensitivity analyses were performed for both models to evaluate the impact of varying modality of IVIG treatments and proportion of patients switching from IVIG to SCIG. RESULTS: The cost-minimisation model estimated that SCIG treatment reduced cost to the healthcare system per patient of $5736 over 3 years, principally because of less use of hospital personnel. This figure varied between $5035 and $8739 depending on modality of IVIG therapy. Assuming 50% of patients receiving IVIG switched to SCIG, the BIM estimated cost savings for the first 3 years at $1·308 million or 37% of the personnel and supply budget. These figures varied between $1·148 million and $2·454 million (36 and 42%) with varying modalities of IVIG therapy. If 75% of patients switched to SCIG, the reduced costs reached $1·962 million or 56% of total budget. CONCLUSION: This study demonstrated that from the health system perspective, rapid push home-based SCIG was less costly than hospital-based IVIG for immunoglobulin replacement therapy in adult PID patients in the Canadian context.


Assuntos
Imunização Passiva/métodos , Imunoglobulinas Intravenosas/uso terapêutico , Síndromes de Imunodeficiência/terapia , Adulto , Colúmbia Britânica , Orçamentos/estatística & dados numéricos , Redução de Custos/estatística & dados numéricos , Gastos em Saúde/estatística & dados numéricos , Serviços Hospitalares de Assistência Domiciliar/economia , Custos Hospitalares/estatística & dados numéricos , Humanos , Imunização Passiva/economia , Imunoglobulinas Intravenosas/economia , Síndromes de Imunodeficiência/economia , Infusões Intravenosas/economia , Injeções Subcutâneas/economia , Salários e Benefícios/estatística & dados numéricos
6.
Climacteric ; 14(2): 282-8, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21244215

RESUMO

OBJECTIVE: To examine the effect of intravaginal dehydroepiandrosterone (DHEA) on pain at sexual activity (dyspareunia) identified as the most bothersome symptom of vaginal atrophy in postmenopausal women at both screening and day 1. METHODS: This prospective, randomized, double-blind and placebo-controlled phase III clinical trial studied the effect of prasterone (DHEA) applied locally in the vagina on the severity of dyspareunia in 114 postmenopausal women who had identified dyspareunia as their most bothersome symptom of vaginal atrophy, while meeting the criteria for superficial cells ≤ 5% and pH > 5.0 at both screening and day 1. RESULTS: At the standard duration of 12 weeks of treatment, increasing doses of 0.25%, 0.5% and 1.0% DHEA decreased the percentage of parabasal cells by 48.6  ±â€Š 6.78%, 42.4  ±  7.36% and 54.9  ±â€Š 6.60% (p < 0.0001 vs. placebo for all) with no change with placebo (p = 0.769). The effects on superficial cells and pH were also highly significant compared to placebo at all DHEA doses. The severity score of pain at sexual activity decreased by 0.5, 1.4, 1.6 and 1.4 units in the placebo and 0.25%, 0.5% and 1.0% DHEA groups, respectively, with the p value of differences from placebo ranging from 0.0017 to < 0.0001. CONCLUSIONS: Intravaginal DHEA, through local estrogen and androgen formation, causes a rapid and highly efficient effect on pain at sexual activity without systemic exposure of the other tissues, thus avoiding the recently reported systemic effects of estrogens.


Assuntos
Desidroepiandrosterona/administração & dosagem , Dispareunia/tratamento farmacológico , Administração Intravaginal , Desidroepiandrosterona/uso terapêutico , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Pós-Menopausa , Resultado do Tratamento
7.
EuroIntervention ; 5(6): 716-21, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20142224

RESUMO

AIMS: Mortality of massive pulmonary embolism remains exceedingly high despite thrombolytic therapy. Despite initial encouraging results, rheolytic thrombectomy has not been considered the first choice of treatment in the current European Guidelines for massive pulmonary embolism, even in cases of major contraindication to thrombolysis. Our objective was to assess the efficacy of rheolytic thrombectomy in the specific treatment of massive pulmonary embolism with contraindication to systemic thrombolytic therapy. METHODS AND RESULTS: Between January 2003 and April 2008 a total of 10 patients with massive pulmonary embolism referred for rheolytic thrombectomy were included. Clinical data including medical history, haemodynamic status, procedural characteristic, in-hospital complications and survival were collected. Seven patients survived after undergoing the procedure, three patients died in during their initial hospitalisation however, two of these deaths were not attributable to the pulmonary embolism or the procedure. Rheolytic thrombectomy resulted in reduction of mean pulmonary artery pressures from 34.6+/-13.1 mmHg to 26.9+/-8.2 mmHg immediately following the procedure. Additionally, the Miller index improved from 22.4+/-2.8 to 9.8+/-2.7. There were no periprocedural bleeding complications associated with the procedure. CONCLUSIONS: Rheolytic thrombectomy might be an effective and safe treatment for massive pulmonary embolism when systemic thrombolytic therapy is contraindicated. These data form the basis for further clinical investigation of this novel therapy among patients with massive pulmonary embolism.


Assuntos
Embolia Pulmonar/cirurgia , Trombectomia/instrumentação , Terapia Trombolítica , Adolescente , Adulto , Idoso , Contraindicações , Ecocardiografia Doppler , Desenho de Equipamento , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Embolia Pulmonar/diagnóstico , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto Jovem
8.
Pacing Clin Electrophysiol ; 24(10): 1534-40, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11707048

RESUMO

Modern pacemakers offer many programming options regarding the AV interval including the ability to vary AV intervals depending on whether atrial activity is paced or spontaneous and to shorten AV intervals with increasing rates. To determine if optimization of these features improves exercise tolerance, 14 patients with intact sinus node function and AV block treated with dual chamber pacemakers were enrolled in a randomized double-blind crossover trial. Doppler echocardiographic measurements of cardiac index and mitral flow were assessed over a range of programmable AV intervals at rest to determine each patient's optimal AV interval. Eleven patients completed serial graded exercise tests with spiroergometry after randomly programming the AV interval three ways in a crossover manner: fixed AV interval = 150 ms without rate adaptation (150/Fixed), fixed AVinterval = 150 ms with rate adaptation (150/R), or optimized AV interval with rate adaptive AV interval shortening (optimized/R). Exercise capacity was determined by maximum oxygen uptake. Ten men and four women, age 64 +/- 8 years, were enrolled. At rest, optimization of the AVintervalimproved the cardiac index by 21% (P < 0.001) and mitral flow by 13.4% (P < 0.001) when compared to least-favorable AV intervals. During exercise, no differences in maximum heart rates were noted. Maximum oxygen uptake was increased in both groups with rate adaptive AVinterval shortening when compared tofixed AVinterval without rate adaptation: 13.9% (adjusted P < 0.04) and 14.6% (adjusted P < 0.02) in optimized/R and 150/R, respectively. No differences were noted between optimized/R and 150/R. In conclusion, rate adaptive AV interval shortening improved exercise tolerance independent of changes in heart rate. However, optimization of the AV interval with Doppler echocardiography at rest did not further improve exercise capacity.


Assuntos
Função Atrial , Tolerância ao Exercício , Marca-Passo Artificial , Função Ventricular , Estudos Cross-Over , Método Duplo-Cego , Ecocardiografia Doppler , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
9.
Mol Cell Endocrinol ; 173(1-2): 15-27, 2001 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-11223174

RESUMO

Grb10 is a member of a family of adapter proteins that binds to tyrosine-phosphorylated receptors including the insulin receptor kinase (IRK). In this study recombinant adenovirus was used to over-express hGrb10zeta, a new Grb10 isoform, in primary rat hepatocytes and the consequences for insulin signaling were evaluated. Over-expression of hGrb10zeta resulted in 50% inhibition of insulin-stimulated IRK autophosphorylation and activation. Analysis of downstream events showed that hGrb10zeta over-expression specifically inhibits insulin-stimulated glycogen synthase (GS) activity and glycogen synthesis without affecting insulin-induced IRS1/2 phosphorylation, PI3-kinase activation, insulin like growth factor binding protein-1 (IGFBP-1) mRNA expression, and ERK1/2 MAP kinase activity. The classical pathway from PI3-kinase through Akt-PKB/GSK-3 leading to GS activation by insulin was also not affected by hGrb10zeta over-expression. These results indicate that hGrb10zeta inhibits a novel and presently unidentified insulin signaling pathway leading to GS activation in liver.


Assuntos
Glicogênio Sintase/metabolismo , Insulina/farmacologia , Proteínas/metabolismo , Animais , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Células Cultivadas , Ativação Enzimática/efeitos dos fármacos , Proteína Adaptadora GRB10 , Glicogênio/biossíntese , Quinase 3 da Glicogênio Sintase , Hepatócitos/efeitos dos fármacos , Hepatócitos/enzimologia , Hepatócitos/metabolismo , Humanos , Insulina/metabolismo , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Masculino , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Compostos Organometálicos/farmacologia , Fenantrolinas/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Tirosina Fosfatases/antagonistas & inibidores , Proteínas/genética , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptor de Insulina/antagonistas & inibidores , Receptor de Insulina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transcrição Gênica/efeitos dos fármacos
10.
J Biol Chem ; 274(40): 28279-85, 1999 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-10497184

RESUMO

We examined the signaling pathways regulating glycogen synthase (GS) in primary cultures of rat hepatocytes. The activation of GS by insulin and glucose was completely reversed by the phosphatidylinositol 3-kinase inhibitor wortmannin. Wortmannin also inhibited insulin-induced phosphorylation and activation of protein kinase B/Akt (PKB/Akt) as well as insulin-induced inactivation of GS kinase-3 (GSK-3), consistent with a role for the phosphatidylinositol 3-kinase/PKB-Akt/GSK-3 axis in insulin-induced GS activation. Although wortmannin completely inhibited the significantly greater level of GS activation produced by the insulin-mimetic bisperoxovanadium 1,10-phenanthroline (bpV(phen)), there was only minimal accompanying inhibition of bpV(phen)-induced phosphorylation and activation of PKB/Akt, and inactivation of GSK-3. Thus, PKB/Akt activation and GSK-3 inactivation may be necessary but are not sufficient to induce GS activation in rat hepatocytes. Rapamycin partially inhibited the GS activation induced by bpV(phen) but not that effected by insulin. Both insulin- and bpV(phen)-induced activation of the atypical protein kinase C (zeta/lambda) (PKC (zeta/lambda)) was reversed by wortmannin. Inhibition of PKC (zeta/lambda) with a pseudosubstrate peptide had no effect on GS activation by insulin, but substantially reversed GS activation by bpV(phen). The combination of this inhibitor with rapamycin produced an additive inhibitory effect on bpV(phen)-mediated GS activation. Taken together, our results indicate that the signaling components mammalian target of rapamycin and PKC (zeta/lambda) as well as other yet to be defined effector(s) contribute to the modulation of GS in rat hepatocytes.


Assuntos
Glicogênio Sintase/metabolismo , Fígado/enzimologia , Proteínas Serina-Treonina Quinases , Transdução de Sinais , Animais , Células Cultivadas , Ativação Enzimática , Glucose/farmacologia , Insulina/farmacologia , Fígado/citologia , Fígado/efeitos dos fármacos , Masculino , Fenantrolinas/farmacologia , Fosforilase Fosfatase/metabolismo , Fosforilases/antagonistas & inibidores , Proteína Quinase C/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt , Ratos , Ratos Sprague-Dawley
11.
Biochem J ; 325 ( Pt 3): 727-32, 1997 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-9271094

RESUMO

In skeletal muscle, acute insulin treatment results in the recruitment of the GLUT4 glucose transporter from intracellular vesicular structures to the plasma membrane. The precise nature of these intracellular GLUT4 stores has, however, remained poorly defined. Using an established skeletal-muscle fractionation procedure we present evidence for the existence of two distinct intracellular GLUT4 compartments. We have shown that after fractionation of crude muscle membranes on a discontinuous sucrose gradient the majority of the GLUT4 immunoreactivity was largely present in two sucrose fractions (30 and 35%, w/w, sucrose; denoted F30 and F35 respectively) containing intracellular membranes of different buoyant densities. Here we show that these fractions contained 44+/-6 and 49+/-7% of the crude membrane GLUT4 reactivity respectively, and could be further discriminated on the basis of their immunoreactivity against specific subcellular antigen markers. Membranes from the F30 fraction were highly enriched in transferrin receptor (TfR) and annexin II, two markers of the early endosome compartment, whereas they were significantly depleted of both GLUT1 and the alpha1-subunit of (Na++K+)-ATPase, two cell-surface markers. Insulin treatment resulted in a significant reduction in GLUT4 content in membranes from the F35 fraction, whereas the amount of GLUT4 in the less dense (F30) fraction remained unaffected by insulin. Immunoprecipitation of GLUT4-containing vesicles from both intracellular fractions revealed that TfR was present in GLUT4 vesicles isolated from membranes from the F30 fraction. In contrast, GLUT4 vesicles from the F35 fraction were devoid of TfR. The aminopeptidase, vp165, was present in GLUT4 vesicles from both F30 and F35; however, vesicles isolated from F30 contained over twice as much vp165 per unit of GLUT4 than those isolated from F35. The biochemical co-localization of vp165/GLUT4 was further substantiated by double-immunogold labelling of ultrathin muscle sections. Overall, our data indicate the presence of at least two internal GLUT4 pools: one possibly derived from an endosomal recycling compartment, and the other representing a specialized insulin-sensitive GLUT4 storage pool. Both pools contain vp165.


Assuntos
Endossomos/metabolismo , Insulina/farmacologia , Proteínas de Transporte de Monossacarídeos/metabolismo , Proteínas Musculares , Músculo Esquelético/efeitos dos fármacos , Aminopeptidases/metabolismo , Animais , Compartimento Celular , Cistinil Aminopeptidase , Transportador de Glucose Tipo 4 , Masculino , Microscopia Eletrônica , Músculo Esquelético/metabolismo , Músculo Esquelético/ultraestrutura , Ratos , Ratos Sprague-Dawley
12.
Biochemistry ; 36(25): 7726-32, 1997 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-9201913

RESUMO

The Na+-K+-ATPase consists of alpha and beta subunits proposed to function as an alpha-beta heterodimer. Skeletal muscle is characterized by expression of alpha1, alpha2, beta1, and beta2 subunit isoforms. The relative molar proportions of each subunit or each protein isoform are not known, yet their subcellular distribution and expression in muscles of different fiber types are markedly different. In this study, the molar ratio of each pump subunit isoform was measured in purified membranes from skeletal muscle and compared with those in kidney and brain microsomes. Recombinant proteins were used as standards to quantitate each isoform by immunoblotting in combination with measurements of [3H]ouabain binding. The results indicate that in kidney microsomes, which express predominantly alpha1 and beta1 isoforms, the alpha:beta subunit molar ratio is approximately 1:1. In brain microsomes, the sum of all alpha (alpha1, alpha2, and alpha3) and all beta (beta1 and beta2) subunits also yielded a molar ratio of approximately 1:1. In contrast, in red (oxidative) skeletal muscles, the all alpha:beta subunit ratio was 0.2 in plasma membranes and 0.4 in intracellular membranes. The ratio of alpha2 subunits to alpha1 subunits ranged from 1.6 in surface membranes to up to 7 in internal membranes, while the beta1 subunits exceeded the beta2 subunits by approximately 4-fold in all membrane fractions. Thus, intracellular membranes of red skeletal muscles contain primarily alpha2 and beta1 subunits. When these intracellular membranes were further subfractionated by velocity gradient centrifugation, the alpha2:beta1 subunit ratio was 0.5 in the faster migrating (larger) membranes and 1.0 in the slower migrating (smaller) ones. This was due to a progressive decrease in abundance of the beta1 subunits without a change in the concentration of alpha2 subunits per unit protein. The Na+-K+-ATPase hydrolytic activity was higher in the larger vesicles than in the smaller ones along the sucrose gradient. These results suggest that the ratio of beta to alpha subunits may serve to regulate the catalytic activity of the Na+-K+-ATPase in skeletal muscle.


Assuntos
Membranas Intracelulares/enzimologia , Músculo Esquelético/enzimologia , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Fracionamento Celular , Músculo Esquelético/ultraestrutura , Ratos
13.
Am J Physiol ; 270(5 Pt 1): C1421-9, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8967443

RESUMO

We have previously shown that an acute insulin treatment induces redistribution of the alpha 2- and beta 1- isoforms of the Na+-K+-ATPase from intracellular membranes to plasma membranes detected on subcellular fractionation of mixed muscles and immunoblotting with isoform-specific antibodies (H. S. Hundal et al. J. Biol. Chem. 267: 5040-5043, 1992). In the present study we give both biochemical and morphological evidence that this insulin effect is operative in muscles composed mostly of oxidative (red) fibers but not in muscles composed mostly of glycolytic (white) fibers. The redistribution of the Na+-K+-ATPase alpha 2- and beta 1-isoforms after insulin injection was detected in membranes isolated from and muscles (soleus, red gastrocnemius, red rectus femoris, and red vastus lateralis) but not in membranes from white muscles (white gastrocnemius, tensor fasciae latae, white rectus femoris, and white vastus lateralis). After insulin injection, the potassium-dependent 3-O-methylfluorescein phosphatase activity of the enzyme was higher by 22% in the plasma membrane-enriched fraction and lower by 15% in the internal membrane fraction isolated from red but not from white muscles. Quantitative immunoelectron microscopy of ultrathin muscle cryosections showed that in vivo insulin stimulation augmented the density of Na+-K+-ATPase alpha 2- and beta 1- isoforms at the plasma membrane of soleus muscle by 80 and 124%, respectively, with no change in white gastrocnemius muscle. The effect of insulin to increase the content of Na+-K+-ATPase alpha 2- and beta 1-subunits in isolated plasma membranes was still observed when glycemia was prevented from dropping by using hyperinsulinemic-euglycemic clamps. We conclude that the insulin-induced redistribution of the alpha 2- and beta 1-isoforms of the Na+-K+-ATPase from an intracellular pool to the plasma membrane in restricted to oxidative fiber-type skeletal muscles. This may be related to the selective expression of beta 1-subunits in these fibers and implies that the beta 2-subunit, typical of glycolytic muscles, does not sustain translocation of alpha 2 beta 2-complexes.


Assuntos
Insulina/farmacologia , Fibras Musculares Esqueléticas/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Membrana Celular/metabolismo , Glicólise , Hiperinsulinismo/metabolismo , Masculino , Microscopia Imunoeletrônica , Oxirredução , Ratos , Ratos Sprague-Dawley , Valores de Referência , ATPase Trocadora de Sódio-Potássio/ultraestrutura , Frações Subcelulares/metabolismo
14.
FEBS Lett ; 366(2-3): 109-14, 1995 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-7789525

RESUMO

The GLUT4 glucose transporter and the alpha 2 subunit of the Na+,K(+)-ATPase of rat skeletal muscle are two proteins which redistribute from intracellular membranes to plasma membranes following in vivo insulin stimulation. Here we show that although both proteins co-segregate after subcellular fractionation of unstimulated rat hindlimb muscles, they do not share the same intracellular residence inside the muscle fibre. By immunogold single- and double-labeling on ultrathin muscle cryosections with specific antibodies, the GLUT4 glucose transporter and the Na+,K(+)-ATPase alpha 2 subunit were observed on different vesicular structures within the cell. GLUT4 was detected on subsarcolemmal and perinuclear membranes, and at the junction between myofibrillar A and I bands where triads are localized. The alpha 2 subunit of the Na+,K(+)-ATPase was observed at the plasma membrane and in distinct subsarcolemmal vesicles and intermyofibrillar membranes. Quantitative analysis of double-labeling of GLUT4 and Na+,K(+)-ATPase alpha 2 subunit revealed that less than 6% of the two proteins co-localize in the same continuous vesicular structures. The differential intracellular localization of the two proteins was further confirmed by immunopurification of GLUT4-containing membranes from muscle homogenates, in which the alpha 2 subunit of the Na+,K(+)-ATPase was found only at the same extent as the alpha 1 subunit of the enzyme, a protein exclusively present at the plasma membrane.


Assuntos
Proteínas de Escherichia coli , Glicosídeo Hidrolases , Membranas Intracelulares/metabolismo , Proteínas de Transporte de Monossacarídeos/metabolismo , Proteínas Musculares/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Proteínas de Bactérias/química , Transportador de Glucose Tipo 4 , Glicosiltransferases/química , Imuno-Histoquímica , Insulina/farmacologia , Masculino , Dados de Sequência Molecular , Músculos/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Frações Subcelulares/química
15.
Biotechnol Bioeng ; 44(8): 930-43, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18618911

RESUMO

Embryogenic cultures of a transformed Eschscholtzia californica cell line were carried out in a 11-L helical ribbon impeller bioreactor operated under various conditions to evaluate the performance of this equipment for somatic embryo (SE) production. All bioreactor cultures produced SE suspensions with maximum concentrations at least comparable to those obtained from flask control cultures ( approximately 8-13 SE . mL(-;1)). However, an increase of the mixingspeed, from 60 to 100 rpm, and low sparging rate ( approximately 0.05 VVM, k(L) a approximately 6.1 h(-;1)) for dissolved oxygen concentration (DO) control yielded poorer quality embryogenic cultures. The negative effects on SE production were attributed mainly to the low but excessive shear experienced by the embryogenic cells and/or embryoforming aggregates. High DO ( approximately 60% of air saturation) conditions favored undifferentrated biomass production and high nutrient uptake rates at the expense of the slower SE differentiation process in both flask and bioreactor cultures. Too low DO (-5-10%) inhibited biomass and SE production. The best production of SE ( approximately 44 SE . mL(-1) or approximately 757 SE . g dw(-1) . d(-1)) was achieved by operating the bioreactor at 60 rpm while controlling DO at approximately 20%by surface oxygenation only (0.05 VVM, k(L) a approximately 1.4 h(-;1)). This production was found to be a biomass production/growth-associated process and was mainly limited by the availability of extracellular phosphate, magnesium, nitrogen salts, and carbohydrates. (c) 1994 John Wiley & Sons, Inc.

16.
Am J Obstet Gynecol ; 171(2): 372-8; discussion 378-9, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8059815

RESUMO

OBJECTIVE: The purpose of this study was to determine how cocaine and crack binging affected perinatal complications. STUDY DESIGN: Between Jan. 1 and Dec. 31, 1989, patterns of cocaine-crack binging and perinatal consequences in 905 pregnant women from multiethnic, multiracial, inner-city populations were studied. Binging cycles reflect the chaotic lifestyle of drug abuse and multiple obstetric at-risk cofactors as integral parts of binging and are more accurately defined than amount of drugs consumed. RESULTS: Binging patterns in 905 pregnant women who use cocaine-crack as their primary drug were as follows: group 1, 78 women with "erratic" binging that is variable in intervals, duration, and amounts but who are very aggressive drug seekers; group 2, 67 women who binged daily; group 3, 760 women who binged in cycles at 3-, 5-, 7-, or > 7-day intervals. Binges ranged from 26.4 to 34.4 hours. Complications were proportional to the frequency of binging, (linear association p < 0.0007). The prematurity rate in group 1 was unexpectedly as high as that in group 2 (35.9% vs 34.3%). Acute problems (vaginal bleeding 21.8%, abruptio placentae 14.3%, stillbirths 20.5%) were most significant in group 1, while chronic problems (small-for-gestational-age infants 32.8%, systemic infections 31.3%, anemia 35.6%, and low maternal weight [< 100 pounds] 32.8%) were more significant in groups 2 and 3. Odds ratios show that prematurity, abruptio placentae, and vaginal bleeding were two to three times more likely to occur if test results for cocaine were positive at delivery. However, in group 1 the likelihood of abruptio placentae was unchanged whether toxicologic test results were positive (14.3%) or negative (14.0%), reflecting the role of cofactors in binging. CONCLUSION: Erratic use of cocaine-crack results in perinatal complications that are as severe as those occurring with daily binging but the patterns differ. Cofactors play a significant role in outcomes.


Assuntos
Cocaína/administração & dosagem , Complicações na Gravidez/induzido quimicamente , Resultado da Gravidez , Transtornos Relacionados ao Uso de Substâncias/complicações , Adulto , Análise de Variância , Feminino , Morte Fetal/etiologia , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Recém-Nascido Pequeno para a Idade Gestacional , Gravidez
17.
Am J Cardiol ; 73(2): 191-4, 1994 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-8296742

RESUMO

Percutaneous ablation of accessory pathways was performed in 22 consecutive children and adolescents (9 boys and 13 girls, age range 8 to 18 years). Low-energy direct current (DC) was used exclusively in the first 6 patients, whereas ablation was performed with radiofrequency energy in the following 16. Accessory pathways were located in the left free wall in 15 patients, were posteroseptal in 3, were in the right free wall in 3 and were anteroseptal in 1. A concealed accessory pathway was present in 7 patients (32%). There was no significant difference in clinical or electrophysiologic variables between both groups. Catheter ablation was successful in the initial 6 patients using low-energy DC, as compared with 13 of 16 patients using radiofrequency ablation. Low-energy DC was successful as a backup power source in all 3 patients who had unsuccessful radiofrequency ablation. There was no complication. The median procedural and fluoroscopic times for successful ablation were 2.5 hours and 49 minutes, respectively (p = NS between both power sources). Accessory pathway conduction recurred in 2 patients (33%) who had low-energy DC as compared with 1 (6%) who had radiofrequency ablation (p = NS). These 3 patients had successful reablation of their accessory pathways. In children and adolescents with accessory pathways, both new power sources compare favorably, with an overall success rate of ablation of 100% (22 of 22 patients). Radiofrequency ablation should be used initially because it does not require general anesthesia and is associated with a lower rate of recurrence of accessory pathway conduction.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Ablação por Cateter/métodos , Síndrome de Wolff-Parkinson-White/cirurgia , Adolescente , Criança , Feminino , Sistema de Condução Cardíaco/fisiopatologia , Sistema de Condução Cardíaco/cirurgia , Humanos , Masculino , Resultado do Tratamento , Síndrome de Wolff-Parkinson-White/fisiopatologia
18.
Br Heart J ; 70(6): 580-4, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8280531

RESUMO

OBJECTIVE: To compare two new power sources for catheter ablation in patients with the Wolff-Parkinson-White syndrome. DESIGN: 120 consecutive patients with accessory pathways had catheter ablation. Low energy direct current (DC) was used in the first 60 patients and radio-frequency current in the next 60 patients. SETTING: Electrophysiological laboratory of a large heart institute. PATIENTS: 72 men and 48 women (mean (SD) age 35 (14) years (range 9-75)). The accessory pathways were in the left free wall in 73 patients. They were posteroseptal in 35 patients, in the right free wall in five, and anteroseptal in seven. There was no significant difference in the clinical or electrophysiological variables between the two ablation groups. RESULTS: Catheter ablation with low energy direct current was successful in 55/60 patients (92%) and radiofrequency energy was successful in 52/60 patients (87%). Low energy direct current was also successful in four of the eight patients in whom radiofrequency ablation had failed. Radiofrequency ablation was successful in two of the five patients in whom low energy direct current ablation had failed. The mean (SD) procedure and fluoroscopy times for successful ablation were 3.2 (1.5) h and 61 (40) min respectively. These times were similar for both power sources. Accessory pathway conduction recurred in 17 patients (28%) who had low energy direct current and four patients (7%) who received radiofrequency energy (p < 0.004). All patients with recurrence of an accessory pathway had successful re-ablation. CONCLUSIONS: Both new power sources successfully ablated accessory pathways, (overall success rate 94% (113/120 patients)). Radiofrequency ablation, however, did not require general anaesthesia and was associated with a significantly lower rate of recurrence of accessory pathway conduction. Therefore radiofrequency should be used initially for ablation. Low energy direct current may be most useful as a back-up in patients in whom radiofrequency ablation fails.


Assuntos
Ablação por Cateter/métodos , Eletrocirurgia/métodos , Síndrome de Wolff-Parkinson-White/cirurgia , Adolescente , Adulto , Idoso , Criança , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade
19.
Am J Physiol ; 265(6 Pt 1): C1716-22, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8279532

RESUMO

The cellular localization of the alpha 2-subunit of the Na(+)-K(+)-ATPase was defined by immunoelectron microscopy, and the effect of insulin on the amount of alpha 2-immunoreactive subunits on the cell surface was quantitated. Two protocols were used for tissue fixation and immunolocalization. Protocol 1 was characterized by fixation with 2% paraformaldehyde, use of a monoclonal antibody, and detection with 3-nm-diameter gold-labeled Fab fragments or 10-nm gold-labeled immunoglobulin G. Protocol 2 was characterized by fixation with 4% paraformaldehyde plus 0.1% glutaraldehyde, use of a polyclonal antibody, and detection with 10-nm gold-labeled protein A. In control muscle, the alpha 2-subunit of the Na(+)-K(+)-ATPase was present at the plasma membrane and in intracellular tubular and vesicular structures located in subsarcolemmal and triadic regions. Acute insulin stimulation increased the number of immunolabeled alpha 2-subunits in the plasma membrane after both fixation protocols. The gain in the plasma membrane ranged from 1.5- to 3.7-fold and was significant at the level of P < 0.005. These results provide morphological quantitative evidence that the alpha 2-subunit of the Na(+)-K(+)-ATPase is present both at the plasma membrane and intracellularly in mammalian skeletal muscle and that insulin acutely increases its abundance in the muscle surface.


Assuntos
Insulina/farmacologia , Músculos/enzimologia , ATPase Trocadora de Sódio-Potássio/biossíntese , Animais , Anticorpos Monoclonais , Membrana Celular/efeitos dos fármacos , Membrana Celular/enzimologia , Indução Enzimática , Fragmentos Fab das Imunoglobulinas , Imunoglobulina G , Substâncias Macromoleculares , Microscopia Imunoeletrônica/métodos , Músculos/efeitos dos fármacos , Músculos/ultraestrutura , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/farmacologia , Sarcolema/enzimologia , Sarcolema/ultraestrutura , ATPase Trocadora de Sódio-Potássio/análise
20.
Clin Invest Med ; 16(6): 409-14, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7516829

RESUMO

Monoclonal and polyclonal antibodies were produced using a pure preparation of prostate-specific antigen (PSA) as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). By SDS-PAGE, the apparent molecular weight of PSA was about 33 kD. Eighty-four monoclonal antibodies were produced, 77 of which bind PSA with an affinity higher than 10(9) M-1. Use of these monoclonal antibodies to study the immunological characteristics of PSA revealed the presence of 4 epitopes. Injection of PSA into goats resulted in a production of polyclonal antibodies with high affinity. These polyclonal antibodies were purified by affinity chromatography and adsorbed on plastic tubes. By an immunometric assay, we have also demonstrated that polyclonal antibodies bind PSA at a fifth epitope that is different from those of monoclonal antibodies. Using an iodinated monoclonal antibody and polyclonal antibodies adsorbed on plastic tubes, a sensitive immunoradiometric assay could be developed, and a further increase in sensitivity could be achieved by using a mixture of 2 monoclonal antibodies. The serum PSA levels in 2,250 patients measured with this immunoradiometric assay were identical to the values determined by Tandem-R, although the present assay reached a minimum detectable value of 0.05 ng/ml compared with 0.2 ng/ml by Tandem-R.


Assuntos
Anticorpos Monoclonais/biossíntese , Antígeno Prostático Específico/sangue , Antígeno Prostático Específico/imunologia , Animais , Formação de Anticorpos , Fusão Celular , Eletroforese em Gel de Poliacrilamida , Epitopos/análise , Cabras , Humanos , Imunização , Ensaio Imunorradiométrico , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Dodecilsulfato de Sódio
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