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1.
J Assist Reprod Genet ; 35(5): 735-751, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29497954

RESUMO

An equilibrium needs to be established by the cellular and acellular components of the ovarian follicle if developmental competence is to be acquired by the oocyte. Both cumulus cells (CCs) and follicular fluid (FF) are critical determinants for oocyte quality. Understanding how CCs and FF influence oocyte quality in the presence of deleterious systemic or pelvic conditions may impact clinical decisions in the course of managing infertility. Given that the functional integrities of FF and CCs are susceptible to concurrent pathological conditions, it is important to understand how pathophysiological factors influence natural fertility and the outcomes of pregnancy arising from the use of assisted reproduction technologies (ARTs). Accordingly, this review discusses the roles of CCs and FF in ensuring oocyte competence and present new insights on pathological conditions that may interfere with oocyte quality by altering the intrafollicular environment.


Assuntos
Células do Cúmulo , Líquido Folicular/fisiologia , Oócitos/fisiologia , Animais , Células do Cúmulo/citologia , Células do Cúmulo/fisiologia , Diabetes Mellitus/patologia , Endometriose/patologia , Feminino , Líquido Folicular/citologia , Humanos , Infertilidade Feminina/etiologia , Infertilidade Feminina/patologia , Obesidade/complicações , Obesidade/patologia , Oócitos/citologia , Infecção Pélvica/complicações , Infecção Pélvica/patologia , Síndrome do Ovário Policístico , Gravidez
2.
Reprod Sci ; 21(12): 1465-71, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24675987

RESUMO

UNLABELLED: The etiology of endometriosis remains poorly understood but circulating stem cells may contribute. Telomeres shorten with cell divisions and age. Stem cells attempt to compensate for telomere attrition through the action of telomerase. Since circulating stem cells may contribute to endometriosis, we compared telomere content in lymphocytes of patients with and without endometriosis. METHODS: Observational study comparing peripheral lymphocytes telomere content, measured by quantitative polymerase chain reaction, in patients with (n = 86) and without endometriosis (n = 21). FINDINGS: Patients with endometriosis had longer telomeres than that of matched, endometriosis-free controls (telomere to single copy gene ratio [T/S ratio] of 1.62 vs 1.34, respectively, P = .00002). Patients with endometriosis were 8.1-fold more likely to have long telomeres. (odds ratio = 8.1, 95% confidence interval: 1.28-51.57, P = .0264). INTERPRETATION: Longer telomeres could be consistent with a stem cell origin of endometriosis.


Assuntos
Endometriose/genética , Linfócitos/metabolismo , Homeostase do Telômero , Telômero/genética , Adulto , Estudos de Casos e Controles , Endometriose/sangue , Endometriose/diagnóstico , Feminino , Marcadores Genéticos , Humanos , Reação em Cadeia da Polimerase , Telômero/metabolismo
3.
J Hum Hypertens ; 27(5): 321-7, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23076450

RESUMO

Most patients with hypertension need more than one drug to achieve blood pressure (BP) control. This randomized, double-blind, multifactorial study evaluated whether combinations of aliskiren and amlodipine provided superior BP reductions to component monotherapies in patients with hypertension (mean sitting diastolic BP (msDBP) 95-<110 mm Hg). Overall, 1688 patients were randomized to once-daily monotherapy with aliskiren 150 or 300 mg or amlodipine 5 or 10 mg, combination therapy with one of four corresponding aliskiren/amlodipine doses, or placebo for 8 weeks. At week 8 end point, aliskiren/amlodipine combinations provided significant msDBP reductions from baseline of 14.0-16.5 mm Hg, compared with reductions of 8.0 and 10.2 mm Hg for aliskiren 150 and 300 mg, respectively (P<0.001), and 11.0 and 13.8 mm Hg for amlodipine 5 and 10 mg, respectively (P<0.05). Aliskiren/amlodipine combinations provided reductions in mean sitting systolic BP 20.6-23.9 mm Hg, compared with decreases of 10.7 and 15.4 mm Hg for aliskiren 150 and 300 mg, respectively (P<0.001), and 15.8 and 21.0 mm Hg for amlodipine 5 (P< or =0.001) and 10 mg (P=NS), respectively. Aliskiren/amlodipine combination therapy provides greater BP lowering than either agent alone, hence offering an effective treatment option for patients with hypertension.


Assuntos
Amidas/administração & dosagem , Anlodipino/administração & dosagem , Bloqueadores dos Canais de Cálcio/administração & dosagem , Fumaratos/administração & dosagem , Hipertensão/tratamento farmacológico , Renina/antagonistas & inibidores , Adulto , Idoso , Amidas/efeitos adversos , Amidas/uso terapêutico , Anlodipino/efeitos adversos , Anlodipino/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Monitorização Ambulatorial da Pressão Arterial , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Fumaratos/efeitos adversos , Fumaratos/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade
4.
Am J Cardiovasc Drugs ; 11(5): 327-33, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21846154

RESUMO

BACKGROUND: Hypertension frequently coexists with diabetes mellitus, resulting in increased cardiovascular risk. Thus, BP control is crucial in decreasing morbidity and mortality in this difficult-to-treat patient population. OBJECTIVE: The objective of this study was to evaluate the efficacy and safety of aliskiren in hypertensive patients with diabetes not adequately responsive to the combination of valsartan and hydrochlorothiazide (HCT). METHODS: After a 1- to 4-week washout period, patients with a mean sitting diastolic BP (msDBP) ≥95 mmHg were treated with valsartan 160 mg for 2 weeks followed by valsartan/HCT 160 mg/25 mg for an additional 4 weeks (single-blind active run-in period). Patients whose msDBP remained ≥85 mmHg after the active run-in period were randomized (1 : 1) to receive aliskiren 150 mg (n = 184) or placebo (n = 179) as add-on therapy for 6 weeks. Aliskiren was then force-titrated to 300 mg once daily for another 6 weeks. Efficacy variables were: the change in msDBP and mean sitting systolic BP (msSBP) from baseline to week 12 endpoint, diastolic response (msDBP <80 mmHg or reduction of at least 10 mmHg), and BP control rate (<130/80 mmHg). RESULTS: Of the 363 patients randomized, 328 (90.4%) completed the study (aliskiren and placebo groups: 89.7% and 91.1%, respectively). At week 12 endpoint, the least squares mean (LSM) changes in msDBP (aliskiren vs placebo: -5.8 vs -4.8 mmHg; p = 0.2767) and msSBP (aliskiren vs placebo: -7.3 vs -4.8 mmHg; p = 0.0725) were numerically greater in patients treated with aliskiren compared with those treated with placebo; however, this difference was not statistically significant. The proportion of diastolic responders (aliskiren and placebo: 68.5% and 72.9%, respectively; p = 0.8482) and patients achieving BP control (aliskiren and placebo: 16.0% and 16.4%, respectively; p = 0.7511) were similar for both groups. Overall, 63 (34%) and 59 (33%) patients in the aliskiren and placebo groups, respectively, experienced adverse events (AEs). The most commonly reported AEs were headache (placebo group: 6.1%) and dizziness (aliskiren group: 4.4%). Aliskiren was well tolerated. CONCLUSION: The reductions in BP with aliskiren added to valsartan/HCT in this study were numerically greater compared with placebo added to valsartan/HCT, although not statistically significant.


Assuntos
Amidas/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 2/complicações , Resistência a Medicamentos , Fumaratos/uso terapêutico , Hipertensão/tratamento farmacológico , Idoso , Amidas/administração & dosagem , Amidas/efeitos adversos , Anlodipino/administração & dosagem , Anlodipino/efeitos adversos , Anlodipino/uso terapêutico , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/efeitos adversos , Anti-Hipertensivos/farmacocinética , Relação Dose-Resposta a Droga , Método Duplo-Cego , Quimioterapia Combinada/efeitos adversos , Feminino , Fumaratos/administração & dosagem , Fumaratos/efeitos adversos , Humanos , Hidroclorotiazida/administração & dosagem , Hidroclorotiazida/efeitos adversos , Hidroclorotiazida/uso terapêutico , Hipertensão/sangue , Hipertensão/complicações , Masculino , Pessoa de Meia-Idade , Pacientes Desistentes do Tratamento , Potássio/sangue , Método Simples-Cego
5.
J Hum Hypertens ; 24(11): 721-9, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20200550

RESUMO

Hypertension is a major risk factor for cardiovascular disease, which is the leading cause of mortality in women in developed countries. This pooled analysis assessed the antihypertensive efficacy, safety and tolerability of monotherapy with the direct renin inhibitor aliskiren (150 mg and 300 mg) over 8-12 weeks in women with mild-to-moderate hypertension (mean sitting diastolic blood pressure (msDBP) ≥95 and <110 mm Hg) across eight randomized and double-blind trials. Safety and tolerability were assessed in the five placebo-controlled trials in the analysis. In the 1527 women enrolled in these studies, aliskiren 150 mg and 300 mg produced significantly greater blood pressure (BP) reductions (14.1/11.0 and 16.1/12.3 mm Hg, respectively) compared with placebo (7.2/7.6 mm Hg; P<0.0001). BP reductions with aliskiren monotherapy in women were similar to those observed in men, and consistent across subgroups of age, metabolic syndrome and obesity. The overall incidence of adverse events in women was similar with aliskiren treatment (150 mg, 42.3%; 300 mg, 46.0%) and placebo (39.0%); adverse events with aliskiren were more frequent in women than in men, consistent with previous studies of gender differences in drug tolerability. In conclusion, aliskiren monotherapy at 150 mg and 300 mg doses provided effective, dose-dependent BP-lowering in women with mild-to-moderate hypertension, and it was well tolerated.


Assuntos
Amidas/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Fumaratos/uso terapêutico , Hipertensão/tratamento farmacológico , Renina/antagonistas & inibidores , Idoso , Amidas/efeitos adversos , Anti-Hipertensivos/efeitos adversos , Relação Dose-Resposta a Droga , Feminino , Fumaratos/efeitos adversos , Humanos , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Renina/metabolismo , Fatores Sexuais , Fatores de Tempo , Resultado do Tratamento
6.
J Hum Hypertens ; 24(9): 600-8, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20033075

RESUMO

Efficacy and safety of the direct renin inhibitor aliskiren was compared with ramipril for treatment of essential systolic hypertension in elderly patients. A 36-week, randomized, double-blind, parallel-group, active-controlled, optional-titration study was performed in 901 patients (aliskiren, n=457; ramipril, n=444) > or =65 years of age with systolic blood pressure (SBP) > or =140 mm Hg. Aliskiren 150-300 mg per day or ramipril 5-10 mg per day for was administered for 12 weeks with optional add-on therapy of hydrochlorothiazide (12.5-25 mg per day) at week 12 and amlodipine (5-10 mg per day) at week 22. The primary end point was non-inferiority of aliskiren vs ramipril monotherapy for change from baseline in mean sitting SBP (msSBP) at week 12. Decreases from baseline msSBP and mean sitting diastolic BP with aliskiren monotherapy (-14.0 and -5.1 mm Hg, respectively) were non-inferior (P<0.001 for both values) and superior to ramipril monotherapy (-11.6, -3.6 mm Hg; P=0.02, P<0.01, respectively). More patients achieved BP control with aliskiren (42%) than ramipril (33%; P<0.01). At week 36, fewer patients receiving aliskiren-based therapy required add-on treatment with hydrochlorothiazide or amlodipine (P=0.01 and 0.048, respectively). Tolerability was similar, but more patients receiving ramipril reported cough (P<0.001). In elderly patients with systolic hypertension, aliskiren proved to be more effective and better overall anti-hypertensive therapy compared to ramipril.


Assuntos
Amidas/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Fumaratos/uso terapêutico , Hipertensão/tratamento farmacológico , Ramipril/uso terapêutico , Renina/antagonistas & inibidores , Idoso , Amidas/efeitos adversos , Amidas/farmacologia , Anti-Hipertensivos/efeitos adversos , Método Duplo-Cego , Feminino , Fumaratos/efeitos adversos , Fumaratos/farmacologia , Humanos , Masculino , Ramipril/efeitos adversos , Resultado do Tratamento
7.
J Hum Hypertens ; 24(2): 93-103, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19458624

RESUMO

Most patients inadvertently miss an occasional dose of antihypertensive therapy, and hence drugs that provide sustained blood-pressure (BP) reduction beyond the 24-h dosing interval are desirable. The primary objective of this study was to compare the 24-h mean ambulatory BP reductions from baseline after a simulated missed dose of the direct renin inhibitor aliskiren, irbesartan or ramipril. In this double-blind study, 654 hypertensive patients (24-h mean ambulatory diastolic BP (MADBP) >or=85 mm Hg) were randomized 1:1:1 to once-daily aliskiren 150 mg, irbesartan 150 mg or ramipril 5 mg. Doses were doubled after 2 weeks. At day 42, patients were again randomized equally within each group to receive 1 day of placebo ('missed dose') on either day 42 or day 49. Patients with a successful 24-h ambulatory BP measurement at baseline and on day 42/49 were included in the analyses. The 24-h mean ambulatory systolic BP (MASBP)/MADBP reductions from baseline after a missed dose of aliskiren 300 mg (9.3/7.0 mm Hg) were similar to irbesartan 300 mg (9.5/7.3 mm Hg) and significantly larger than ramipril 10 mg (7.1/5.0 mm Hg, P

Assuntos
Amidas/administração & dosagem , Bloqueadores do Receptor Tipo 1 de Angiotensina II/administração & dosagem , Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Anti-Hipertensivos/administração & dosagem , Compostos de Bifenilo/administração & dosagem , Pressão Sanguínea/efeitos dos fármacos , Fumaratos/administração & dosagem , Hipertensão/tratamento farmacológico , Adesão à Medicação , Ramipril/administração & dosagem , Tetrazóis/administração & dosagem , Adulto , Idoso , Amidas/efeitos adversos , Bloqueadores do Receptor Tipo 1 de Angiotensina II/efeitos adversos , Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Anti-Hipertensivos/efeitos adversos , Compostos de Bifenilo/efeitos adversos , Monitorização Ambulatorial da Pressão Arterial , Brasil , Canadá , Método Duplo-Cego , Esquema de Medicação , Europa (Continente) , Feminino , Fumaratos/efeitos adversos , Humanos , Hipertensão/fisiopatologia , Irbesartana , Masculino , Pessoa de Meia-Idade , Ramipril/efeitos adversos , Tetrazóis/efeitos adversos , Fatores de Tempo , Resultado do Tratamento
8.
Minerva Med ; 100(5): 371-83, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19910890

RESUMO

The lifetime risks for both breast and ovarian cancer for BRCA mutation carriers far exceeds the general population risk of 13% for breast cancer and 1.4% for ovarian cancer. BRCA carriers have unique and medically complicated decisions to make regarding their cancer treatment or risk reduction. As BRCA testing becomes increasingly common among unaffected individuals in families with a previously documented BRCA mutation, there are a growing number of individuals with unique psychosocial needs and concerns. This review paper describes the BRCA 1/2 population, discusses preimplantation genetic diagnosis (PGD), and describes the decisions and ethical issues related to PGD among the BRCA 1/ 2 population.


Assuntos
Neoplasias da Mama/genética , Tomada de Decisões/ética , Genes BRCA1 , Genes BRCA2 , Heterozigoto , Neoplasias Ovarianas/genética , Diagnóstico Pré-Implantação/ética , Neoplasias da Mama/diagnóstico , Feminino , Aconselhamento Genético , Marcadores Genéticos/genética , Predisposição Genética para Doença , Testes Genéticos , Humanos , Mutação , Neoplasias Ovarianas/diagnóstico , Guias de Prática Clínica como Assunto , Diagnóstico Pré-Natal/ética , Técnicas de Reprodução Assistida/ética , Medição de Risco
9.
Cell Mol Life Sci ; 64(2): 139-43, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17219022

RESUMO

Meiotic dysfunction increasingly afflicts women as they age, resulting in infertility, miscarriage and handicapped offspring. How aging disrupts meiotic function in women remains unclear, but as women increasingly delay childbearing, this issue becomes urgent. Telomeres, which mediate aging in mitotic cells, may also mediate aging during meiosis. Telomeres shorten during DNA replication. In mammals, oocytes remain quiescent, but their precursors replicated during fetal oogenesis. Moreover, eggs ovulated from older women entered meiosis later during fetal oogenesis than eggs ovulated when younger, and therefore underwent more replications. Telomeres also shorten from reactive oxygen, which triggers a DNA repair response, so the prolonged interval between fetal oogenesis and ovulation in some women would further shorten telomeres. Mice normally do not exhibit age-related meiotic dysfunction (interestingly, their telomeres are manyfold longer than telomeres in women), but genetic or pharmacologic shortening of mouse telomeres recapitulates the reproductive aging phenotype of women. This has led to a telomere theory of age-related meiotic dysfunction in women, and underlined the importance to human health of a mechanistic understanding of telomeres and meiosis.


Assuntos
Senescência Celular/genética , Meiose/fisiologia , Não Disjunção Genética/genética , Reprodução/genética , Telômero/fisiologia , Animais , Senescência Celular/fisiologia , Feminino , Humanos , Camundongos , Reprodução/fisiologia , Fuso Acromático/fisiologia , Telômero/genética
10.
11.
Hum Reprod ; 21(1): 159-63, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16123085

RESUMO

BACKGROUND: Pre-antral and early antral follicles secrete Müllerian inhibiting substance (MIS), suggesting that MIS may directly reflect ovarian reserve. Since little is known about how ovarian reserve affects oocyte quality, we attempt here to assess the predictive value of MIS on embryo morphology and IVF outcome. To do so, we measured MIS at the time of HCG administration 36 h prior to oocyte retrieval. METHODS: A total of 257 patients undergoing IVF were prospectively recruited. We measured MIS levels by enzyme-linked immunosorbent assay at the time of HCG, and compared the MIS values to day 3 FSH levels in the prediction of embryo morphology and IVF outcome. RESULTS: The distribution of MIS levels was skewed, with a median of 2.7 ng/ml (range 0 to 28.5 ng/ml). MIS values at the time of HCG administration inversely correlated with basal FSH levels (P = 0.002), and both correlated significantly with patient age, number of mature follicles, number of oocytes retrieved and serum estradiol levels. MIS levels correlated significantly with a greater number of 6-cell embryos and better embryo morphology score, while basal FSH levels did not correlate with these outcome variables. MIS levels > or =2.7 ng/ml portended improved oocyte quality as reflected in a higher implantation rate (P = 0.001) and a trend toward a better clinical pregnancy rate (P = 0.084). CONCLUSIONS: MIS levels seem to predict not only ovarian reserve, but also embryo morphology. Measurement of MIS at the time of HCG administration may, therefore, in the future improve management of patients undergoing treatments with assisted reproductive technology.


Assuntos
Gonadotropina Coriônica/administração & dosagem , Embrião de Mamíferos/citologia , Fertilização in vitro , Glicoproteínas/análise , Ovário/química , Hormônios Testiculares/análise , Hormônio Antimülleriano , Feminino , Humanos , Prognóstico , Resultado do Tratamento
12.
J Clin Oncol ; 20(7): 1918-22, 2002 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11919252

RESUMO

PURPOSE: To determine whether cryopreserved solutions of the thrombolytic agent alteplase could be used as a safe, effective, and economically reasonable alternative to urokinase in patients presenting with occluded central venous access devices (CVADs). MATERIALS AND METHODS: Alteplase has been reported as an efficacious alternative to urokinase for treatment of occluded CVADs. However, the practicality of using alteplase as the thrombolytic of choice for this indication remained conjectural. To make this approach economically feasible, alteplase was diluted to 1 mg/mL and 2.5-mL aliquots were stored at -20 degrees C until use. A need to confirm that the cryopreserving and thawing of the reconstituted solution did not compromise the safety and efficacy reported from prior trials was recognized. A quality assessment initiative was undertaken to concurrently monitor the safety and efficacy of this approach. Patients presenting with occluded CVADs received a sufficient volume of the thawed alteplase solution to fill the occluded catheter(s). Data, including efficacy, adverse reactions, dwell time, and catheter type, were collected over a 5-month period. RESULTS: One hundred twenty-one patients accounting for 168 attempted clearances were assessable for safety and efficacy. One hundred thirty-six (81%) of the 168 catheter clearance attempts resulted in successful catheter clearance (95% confidence interval, 74% to 86%). No adverse events were reported. CONCLUSION: Cryopreserved 1-mg/mL aliquots of alteplase are safe and effective in the clearance of occluded CVADs when stored at -20 degrees C for 30 days. The ability to cryopreserve alteplase aliquots makes it an economically reasonable alternative to urokinase in the setting of CVAD occlusion.


Assuntos
Cateterismo Venoso Central/efeitos adversos , Criopreservação/normas , Fibrinolíticos/economia , Fibrinolíticos/uso terapêutico , Ativador de Plasminogênio Tecidual/economia , Ativador de Plasminogênio Tecidual/uso terapêutico , Trombose Venosa/tratamento farmacológico , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Análise Custo-Benefício , Estudos de Viabilidade , Feminino , Fibrinolíticos/efeitos adversos , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Controle de Qualidade , Ativador de Plasminogênio Tecidual/efeitos adversos , Estados Unidos , Trombose Venosa/etiologia
13.
Cell Calcium ; 30(6): 423-33, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11728137

RESUMO

Fertilization triggers cytosolic Ca(2+) oscillations that activate mammalian eggs and initiate development. Extensive evidence demonstrates that Ca(2+) is released from endoplasmic reticulum stores; however, less is known about how the increased Ca(2+) is restored to its resting level, forming the Ca(2+) oscillations. We investigated whether mitochondria also play a role in activation-associated Ca(2+) signaling. Mitochondrial dysfunction induced by the mitochondrial uncoupler FCCP or antimycin A disrupted cytosolic Ca(2+) oscillations, resulting in sustained increase in cytosolic Ca(2+), followed by apoptotic cell death. This suggests that functional mitochondria may participate in sequestering the released Ca(2+), contributing to cytosolic Ca(2+) oscillations and preventing cell death. By centrifugation, mouse eggs were stratified and separated into fractions containing both endoplasmic reticulum and mitochondria and fractions containing endoplasmic reticulum with no mitochondria. The former showed Ca(2+) oscillations by activation, whereas the latter exhibited sustained elevation in cytosolic Ca(2+) but no Ca(2+) oscillations, suggesting that mitochondria take up released cytosolic Ca(2+). Further, using Rhod-2 for detection of mitochondrial Ca(2+), we found that mitochondria exhibited Ca(2+) oscillations, the frequency of which was not different from that of cytosolic Ca(2+) oscillations, indicating that mitochondria are involved in Ca(2+) signaling during egg activation. Therefore, we propose that mitochondria play a crucial role in Ca(2+) signaling that mediates egg activation and development, and apoptotic cell death.


Assuntos
Sinalização do Cálcio/fisiologia , Mitocôndrias/metabolismo , Zigoto/crescimento & desenvolvimento , Animais , Antibacterianos/farmacologia , Antimicina A/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Carbonil Cianeto p-Trifluormetoxifenil Hidrazona/farmacologia , Feminino , Fertilização in vitro/métodos , Masculino , Camundongos , Mitocôndrias/efeitos dos fármacos , Estrôncio/farmacologia , Desacopladores/farmacologia , Zigoto/fisiologia
14.
Am J Physiol Regul Integr Comp Physiol ; 281(6): R2011-20, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11705788

RESUMO

To test the hypothesis that progesterone, independent of estrogen, decreases the plasma osmotic threshold for arginine vasopressin (AVP) release and thirst onset, we compared AVP and thirst responses to hypertonic saline infusion (HSI) during administration of oral contraceptives (OCs) containing progesterone (OCP) with responses to infusion of OCs containing progesterone and estrogen (OCEP). Eight women (29 +/- 2 yr) were infused with 3% NaCl (120 min, 0.1 ml. kg body wt(-1). min(-1)) and consumed fluid (90 min, 15 ml/kg body wt) in the early follicular and midluteal phases of a 28-day menstrual cycle and also after 4 wk of OCP and after 4 wk of OCEP in a randomized crossover design. Baseline plasma osmolality (P(osm)) was lower in the luteal phase (280 +/- 1 mosmol/kgH(2)O) and during OCEP (283 +/- 1 mosmol/kgH(2)O) than in the follicular phase (286 +/- 1 mosmol/kgH(2)O, P < 0.05) but was unaffected by OCP (284 +/- 1 mosmol/kgH(2)O). P(osm) remained lower in the follicular phase than in the luteal phase and with OCEP throughout the first 50 min of HSI. The mean abscissal plasma AVP concentration-P(osm) intercept was unaffected by OCP (267 +/- 1 mosmol/kgH(2)O) but was greater in the follicular phase (273 +/- 2 mosmol/kgH(2)O) than in the luteal phase (266 +/- 4 mosmol/kgH(2)O) and with OCEP (268 +/- 2 mosmol/kgH(2)O, P < 0.05). There were no differences in osmotic thresholds for thirst onset across experimental days. Despite the lower osmotic threshold for AVP release during the luteal phase and with OCEP, fluid balance, renal free water clearance, and Na(+) regulation during HSI were unaffected by menstrual phase or OC treatment, indicating a lower osmotic operating point for body water balance. OCP did not affect osmotic AVP regulation, suggesting that progesterone does not affect osmotic fluid regulation through a mechanism independent of estrogen.


Assuntos
Arginina Vasopressina/farmacologia , Ciclo Menstrual/fisiologia , Progesterona/farmacologia , Equilíbrio Hidroeletrolítico/efeitos dos fármacos , Adulto , Volume Sanguíneo/efeitos dos fármacos , Estradiol/sangue , Feminino , Fase Folicular/efeitos dos fármacos , Humanos , Hidrocortisona/sangue , Fase Luteal/efeitos dos fármacos , Ciclo Menstrual/efeitos dos fármacos , Progesterona/sangue , Sede/efeitos dos fármacos
15.
Hum Reprod ; 16(11): 2374-8, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11679523

RESUMO

BACKGROUND: Spindles are formed from microtubules and are exquisitely sensitive to changes in temperature. An orientation-independent polarized light microscope, the Polscope, can be used to image spindles in living oocytes allowing analysis of spindle kinetics in the living state. This study examined the effects of cooling on spindle disassembly in living human oocytes and spindle recovery after rewarming. METHODS: Oocytes were imaged continuously with the Polscope during cooling and rewarming. The quantity of microtubules in the spindles was measured by its birefringence using the Polscope. RESULTS: Spindles had completely disassembled by 5 min after cooling and recovered by 20 min after rewarming to 37 degrees C if rewarming started soon after the oocyte's temperature dropped to room temperature. However, when oocytes were cooled and kept at 33, 28 or 25 degrees C for 10 min and then warmed, it was found that warming allowed 5/5, 2/5 and 0/5 oocytes of the spindles to recover respectively. CONCLUSIONS: These results indicate that human meiotic spindles are exquisitely sensitive to alterations in temperature. The maintenance of temperature at 37 degrees C during in-vitro manipulation is important for spindle integrity and, therefore, is likely to be important for normal fertilization and subsequent embryo development.


Assuntos
Temperatura Baixa , Temperatura Alta , Meiose , Microscopia de Polarização , Microtúbulos/fisiologia , Microtúbulos/ultraestrutura , Feminino , Humanos
16.
J Appl Physiol (1985) ; 91(4): 1893-901, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11568177

RESUMO

To determine sex differences in osmoregulation of arginine vasopressin (AVP) and body water, we studied eight men (24 +/- 1 yr) and eight women (29 +/- 2 yr) during 3% NaCl infusion [hypertonic saline infusion (HSI); 120 min, 0.1 ml. kg body wt(-1). min(-1)]. Subjects then drank 15 ml/kg body wt over 30 min followed by 60 min of rest. Women were studied in the early follicular (F; 16.1 +/- 2.8 pg/ml plasma 17beta-estradiol and 0.6 +/- 0.1 ng/ml plasma progesterone) and midluteal (L; 80.6 +/- 11.4 pg/ml plasma 17beta-estradiol and 12.7 +/- 0.7 ng/ml plasma progesterone) menstrual phases. Basal plasma osmolality was higher in F (286 +/- 1 mosmol/kgH(2)O) and in men (289 +/- 1 mosmol/kgH(2)O) compared with L (280 +/- 1 mosmol/kgH(2)O, P < 0.05). Neither menstrual phase nor gender affected basal plasma AVP concentration (P([AVP]); 1.7 +/- 4, 1.9 +/- 0.4, and 2.2 +/- 0.5 pg/ml for F, L, and men, respectively). The plasma osmolality threshold for AVP release was lowest in L (x-intercept, 263 +/- 3 mosmol/kgH(2)O, P < 0.05) compared with F (273 +/- 2 mosmol/kgH(2)O) and men (270 +/- 4 mosmol/kgH(2)O) during HSI. Men had greater P([AVP])-plasma osmolality slopes (i.e., sensitivity) compared with F and L (slopes = 0.14 +/- 0.04, 0.09 +/- 0.01, and 0.24 +/- 0.07 for F, L, and men, respectively, P < 0.05). Despite similar Na+-regulating hormone responses, men excreted less Na+ during HSI (0.7 +/- 0.1, 0.7 +/- 0.1, and 0.5 +/- 0.1 meq/kg body wt for F, L, and men, respectively, P < 0.05). Furthermore, men had greater systolic blood pressure (119 +/- 5, 119 +/- 5, and 132 +/- 3 mmHg for F, L, and men, respectively, P < 0.05) than F and L. Our data indicate greater sensitivity in P([AVP]) response to changes in plasma osmolality as the primary difference between men and women during HSI. In men, this greater sensitivity was associated with an increase in systolic blood pressure and pulse pressure during HSI, most likely due to a shift in the pressure-natriuresis curve.


Assuntos
Arginina Vasopressina/fisiologia , Rim/metabolismo , Sódio/metabolismo , Equilíbrio Hidroeletrolítico/fisiologia , Adulto , Algoritmos , Arginina Vasopressina/genética , Volume Sanguíneo/efeitos dos fármacos , Volume Sanguíneo/fisiologia , Água Corporal/efeitos dos fármacos , Água Corporal/fisiologia , Feminino , Genoma , Hemodinâmica/efeitos dos fármacos , Hemodinâmica/fisiologia , Hemoglobinas/metabolismo , Humanos , Masculino , Renina/sangue , Caracteres Sexuais , Equilíbrio Hidroeletrolítico/genética
17.
Semin Oncol ; 28(4 Suppl 12): 2-7, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11552224

RESUMO

The highly active chemotherapeutic agents doxorubicin, duanorubicin, idarubicin, epirubicin, and mitoxantrone are also associated with acute, largely reversible cardiotoxic effects and a dose-related cardiomyopathy. This cardiomyopathy is characterized by minimal left ventricular enlargement and global systolic dysfunction, usually with associated mild to moderate mitral insufficiency. Historically, this was characterized by myocardial biopsy and radionuclide angiography. More recently, echocardiography has become the most widely available and cost-efficient tool for diagnosis. The precise mechanism of this toxicity has not been fully defined. However, the maximum tolerated cumulative dose can by increased by reducing peak drug levels and concurrent administration of the iron chelator, dexrazoxane. Because anthracycline-induced cardiomyopathy is largely irreversible and cumulative, prevention is the preferred strategy. Monitoring by assessment of left ventricular function by the most reproducible method available as patients approach potentially toxic doses can substantially reduce toxicity. Stress studies before major procedures such as bone marrow or stem cell transplants may be of benefit. This syndrome responds well to conventional therapy for congestive heart failure with angiotensin-converting enzyme inhibitors, digoxin, and diuretics. The beta-blocker carvedilol is often associated with significant improvement in ejection fraction and symptoms and spironolactone is well tolerated and often of benefit. The long-term outlook of the syndrome is much better than previously reported because of advances in therapy and prevention.


Assuntos
Antraciclinas/efeitos adversos , Antibióticos Antineoplásicos/efeitos adversos , Cardiopatias/induzido quimicamente , Cardiopatias/prevenção & controle , Humanos
18.
Am J Physiol Regul Integr Comp Physiol ; 281(4): R1319-29, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11557642

RESUMO

The purpose of this study was to determine estrogen (E(2)) and progesterone (P(4)) effects on atrial natriuretic peptide (ANP) control of plasma volume (PV) and transcapillary fluid dynamics. To this end, we suppressed reproductive function in 12 women (age 21-35 yr) using a gonadotropin releasing-hormone (GnRH) analog (leuprolide acetate) for 5 wk. During the 5th week, the women either received 4 days of E(2) administration (17beta-estradiol, transdermal patch, 0.1 mg/day) or 4 days of E(2) with P(4) administration (vaginal gel, 90 mg P(4) twice per day). At the end of the 4th and 5th week of GnRH analog and hormone administration, we determined PV (Evans blue dye) and changes in PV and forearm capillary filtration coefficient (CFC) during a 120-min infusion of ANP (5 ng x kg body wt(-1) x min(-1)). Preinfusion PV was estimated from Evans blue dye measurement taken over the last 30 min of infusion based on changes in hematocrit. E(2) treatment did not affect preinfusion PV relative to GnRH analog alone (45.3 +/- 3.1 vs. 45.4 +/- 3.1 ml/kg). During ANP infusion CFC was greater during E(2) treatment compared with GnRH analog alone (6.5 +/- 1.4 vs. 4.9 +/- 1.4 microl. 100 g(-1) x min(-1) mmHg(-1), P < 0.05). The %PV loss during ANP infusion was similar for E(2) and GnRH analog-alone treatments (-0.8 +/- 0.2 and -1.0 +/- 0.2 ml/kg, respectively), indicating the change in CFC had little systemic effect on ANP-related changes in PV. Estimated baseline PV was reduced by E(2)-P(4) treatment. During ANP infusion CFC was approximately 30% lower during E(2)-P(4) (6.0 +/- 0.5 vs. 4.3 +/- 4.3 microl. 100 g(-1) x min(-1) mm Hg(-1), P < 0.05), and the PV loss during ANP infusion was attenuated (-0.9 +/- 0.2 and -0.2 +/- 0.2 ml/kg for GnRH analog-alone and E(2)-P(4) treatments, respectively). Thus the E(2)-P(4) treatment lowered CFC and reduced PV loss during ANP infusion.


Assuntos
Capilares/efeitos dos fármacos , Capilares/fisiologia , Permeabilidade Capilar/efeitos dos fármacos , Estrogênios/farmacologia , Progesterona/farmacologia , Adulto , Fator Natriurético Atrial/administração & dosagem , Fator Natriurético Atrial/sangue , Pressão Sanguínea/efeitos dos fármacos , Volume Sanguíneo/efeitos dos fármacos , Volume Sanguíneo/fisiologia , Débito Cardíaco/efeitos dos fármacos , Vias de Administração de Medicamentos , Estradiol/farmacologia , Feminino , Fármacos para a Fertilidade Feminina/farmacologia , Antebraço/irrigação sanguínea , Hormônio Liberador de Gonadotropina/efeitos adversos , Hormônio Liberador de Gonadotropina/análogos & derivados , Hormônio Liberador de Gonadotropina/farmacologia , Hematócrito , Fogachos/etiologia , Humanos , Infusões Intravenosas , Leuprolida/efeitos adversos , Leuprolida/farmacologia , Volume Sistólico/efeitos dos fármacos , Veias/fisiologia
20.
Hum Reprod ; 16(7): 1464-8, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11425830

RESUMO

BACKGROUND: Birefringent spindles imaged with the Polscope can predict fertilization rates after intracytoplasmic sperm injection (ICSI). The present study examined the development of human oocytes with or without birefringent spindles, imaged with the Polscope before ICSI. METHODS: Oocytes were obtained from stimulated ovaries of consenting patients undergoing oocyte retrieval for ICSI. Spindles were imaged with the Polscope combined with a computerized image analysis system. After imaging and ICSI, oocytes with or without spindles were cultured separately for examination of fertilization and embryo development. A total of 1544 oocytes from 136 cycles were examined with the Polscope and inseminated by ICSI. RESULTS: Spindles were imaged in 82% of oocytes. After ICSI, more oocytes (P < 0.05) with spindles (69.4%) fertilized normally, forming 2 pronuclei, than oocytes without spindles (62.9%). At day 3, more oocytes (P < 0.01) with spindles (66.3%) developed to 4-11 cell stages than oocytes without spindles (55.4%). Significantly more (P < 0.001) oocytes with spindles developed to morula and blastocyst by day 5 (51.1 versus 30.3%) and day 6 (53.2 versus 29.3%) compared with oocytes without spindles. CONCLUSIONS: The results indicate that the presence of a birefringent spindle in human oocytes can predict not only higher fertilization rate, but also higher embryo developmental competence.


Assuntos
Embrião de Mamíferos/fisiologia , Meiose , Microscopia de Polarização , Oócitos/fisiologia , Oócitos/ultraestrutura , Injeções de Esperma Intracitoplásmicas , Adulto , Birrefringência , Blastocisto/fisiologia , Técnicas de Cultura , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Mórula/fisiologia , Fuso Acromático
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