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1.
Neuroendocrinology ; 111(4): 388-402, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32299084

RESUMO

OBJECTIVES: To conduct a cost-utility analysis comparing drug strategies involving octreotide, lanreotide, pasireotide, and pegvisomant for the treatment of patients with acromegaly who have failed surgery, from a Brazilian public payer perspective. METHODS: A probabilistic cohort Markov model was developed. One-year cycles were employed. The patients started at 45 years of age and were followed lifelong. Costs, efficacy, and quality of life parameters were retrieved from the literature. A discount rate (5%) was applied to both costs and efficacy. The results were reported as costs per quality-adjusted life year (QALY), and incremental cost-effectiveness ratios (ICERs) were calculated when applicable. Scenario analyses considered alternative dosages, discount rate, tax exemption, and continued use of treatment despite lack of response. Value of information (VOI) analysis was conducted to explore uncertainty and to estimate the costs to be spent in future research. RESULTS: Only lanreotide showed an ICER reasonable for having its use considered in clinical practice (R$ 112,138/US$ 28,389 per QALY compared to no treatment). Scenario analyses corroborated the base-case result. VOI analysis showed that much uncertainty surrounds the parameters, and future clinical research should cost less than R$ 43,230,000/US$ 10,944,304 per year. VOI also showed that almost all uncertainty that precludes an optimal strategy choice involves quality of life. CONCLUSIONS: With current information, the only strategy that can be considered cost-effective in Brazil is lanreotide treatment. No second-line treatment is recommended. Significant uncertainty of parameters impairs optimal decision-making, and this conclusion can be generalized to other countries. Future research should focus on acquiring utility data.


Assuntos
Acromegalia/tratamento farmacológico , Acromegalia/economia , Antineoplásicos , Análise Custo-Benefício , Hormônios , Hormônio do Crescimento Humano/análogos & derivados , Octreotida , Avaliação de Resultados em Cuidados de Saúde , Peptídeos Cíclicos , Somatostatina/análogos & derivados , Antineoplásicos/economia , Antineoplásicos/farmacologia , Brasil , Hormônios/economia , Hormônios/farmacologia , Hormônio do Crescimento Humano/economia , Hormônio do Crescimento Humano/farmacologia , Humanos , Programas Nacionais de Saúde , Octreotida/economia , Octreotida/farmacologia , Avaliação de Resultados em Cuidados de Saúde/economia , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Peptídeos Cíclicos/economia , Peptídeos Cíclicos/farmacologia , Somatostatina/economia , Somatostatina/farmacologia
2.
J Vis Exp ; (157)2020 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-32202532

RESUMO

Sexual behavior is highly species-specific. Although rodents have slightly different sexual behaviors, mice and rats have a similar sexual behavioral pattern. The purpose of this article is to describe the hormone-induced estrus ovariectomized female model and the experimental procedure for the assessment of sexual behavior of male mice. The most important sexual behavioral elements are demonstrated in the video and illustrations. The critical steps, advantages, and limitations of the sexual behavior test are explained as well. Finally, the behavior parameters are presented, and mounting, intromission, and ejaculation processes in mating are distinguished. Behavioral parameters are assessed in terms of the occurred duration and counts during the test period.


Assuntos
Comportamento Sexual Animal/fisiologia , Animais , Bioensaio , Ejaculação/fisiologia , Estro/efeitos dos fármacos , Feminino , Habituação Psicofisiológica , Hormônios/farmacologia , Masculino , Camundongos , Ovariectomia , Ratos
3.
Clin Biomech (Bristol, Avon) ; 73: 9-16, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31918023

RESUMO

BACKGROUND: Osteoporosis is a bone disease identified by disordering of bone formation and resorption cells. It increases the risk of bone fragility and fracture. Autocrine and paracrine signalling of osteoclasts and osteoblasts plays an important role in the regulation of bone remodelling. Calcitonin is an approved pharmacologic agent for the treatment of osteoporosis. METHODS: A novel mathematical model comprising the interaction among osteoclasts and osteoblasts cells with intermittent administration of calcitonin has been presented to study the dynamics of osteoporotic bone. The stability of model and sensitivity of parameters are also discussed. FINDINGS: The population of osteoclastic and osteoblastic cells has been predicted via numerical simulation. The results of Monte Carlo sensitivity analysis are shown via tornado diagram. INTERPRETATION: It is concluded that intermittent administration of calcitonin is an effective therapy for the treatment of osteoporosis.


Assuntos
Osso e Ossos/efeitos dos fármacos , Hormônios/farmacologia , Modelos Biológicos , Remodelação Óssea/efeitos dos fármacos , Osso e Ossos/citologia , Osso e Ossos/fisiologia , Humanos , Método de Monte Carlo , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteoclastos/citologia , Osteoclastos/efeitos dos fármacos
4.
Hum Fertil (Camb) ; 22(4): 266-272, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29671650

RESUMO

One factor explaining the declining birth rate in Japan is the social advancement of women. Women are delaying marriage and childbirth, with many then facing so-called 'social infertility'. Advanced infertility treatment options, such as in vitro fertilization, are available, but the costs are high. Further, the success rates for 'older' women are only around 10%. We report the preliminary results of an oocyte cryopreservation programme promoted and subsidized by our city government. Citywide seminars were conducted to generate awareness of issues surrounding fertility. Among the total 81 attendees were women considering oocyte retrieval and the current practice of oocyte retrieval and cryopreservation and its associated risks were explained. Fifty-seven attendees, women under 34 years of age, were considered potential candidates for the procedure. These women wished to delay pregnancy for specific reasons, such as occupational demands. Twenty-six of these women expressed a definite desire for oocyte cryopreservation, and 19 have thus far completed the oocyte retrieval and cryopreservation procedure. Frozen MII oocytes have ranged in number from 3 to 22 per patient (mean ± SD, 8.3 ± 5.2). Outcomes thus far indicate that women whose fertility is at risk can be assisted by this fertility preservation method and that it will help address the problem of the declining birth rate in Japan.


Assuntos
Criopreservação/economia , Financiamento Governamental , Oócitos/fisiologia , Preservação de Tecido/economia , Adulto , Feminino , Hormônio Foliculoestimulante/administração & dosagem , Hormônio Foliculoestimulante/farmacologia , Hormônios/administração & dosagem , Hormônios/farmacologia , Humanos , Japão , Masculino , Coleta de Tecidos e Órgãos , Adulto Jovem
5.
Arch Sex Behav ; 47(4): 953-962, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29313190

RESUMO

In order to reduce gender dysphoria and combat stigma, transgender women often affirm their gender through social and medical transition, which may include cross-sex hormone therapy. This study examined associations between medically monitored hormone use and hormone misuse (non-prescribed hormone use including "fillers"), structural inequities (access to housing, health insurance, and income), and social network dynamics among 271 transgender women in Los Angeles. Hormone use status was coded trichotomously (hormone use, hormone misuse, no hormone use), and robust multinomial logistic regression as well as novel social network analysis was conducted to examine associations. Results demonstrated that younger, African-American/Black transgender women were most likely to engage in hormone misuse compared to transgender women who were older or non-African-American/Black. One-third of the sample reported sex work as a main source of income, and this group was more likely to misuse hormones than those with another primary source of income. Transgender women with access to stable housing and health insurance were most likely to engage in medically monitored hormone use. Social network analysis revealed that transgender women with a greater number of hormone-using network alters were most likely to misuse hormones, but that using the Internet to find transgender friends mitigated this association. Results demonstrate the multifaceted risk profile of transgender women who use and misuse hormones, including that social networks play an important role in hormone usage among transgender women.


Assuntos
Hormônios/efeitos adversos , Hormônios/uso terapêutico , Comportamento Sexual/psicologia , Pessoas Transgênero/psicologia , Adulto , Feminino , Identidade de Gênero , Hormônios/farmacologia , Humanos , Los Angeles , Masculino , Rede Social , Transexualidade
6.
J Dairy Sci ; 98(11): 7426-45, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26342982

RESUMO

The dairy industry in the developed world has undergone profound changes over recent decades. In this paper, we present an overview of some of the most important recent changes in the dairy industry that affect health and welfare of dairy cows, as well as the science associated with these changes. Additionally, knowledge gaps are identified where research is needed to guide the dairy industry through changes that are occurring now or that we expect will occur in the future. The number of farms has decreased considerably, whereas herd size has increased. As a result, an increasing number of dairy farms depend on hired (nonfamily) labor. Regular professional communication and establishment of farm-specific protocols are essential to minimize human errors and ensure consistency of practices. Average milk production per cow has increased, partly because of improvements in nutrition and management but also because of genetic selection for milk production. Adoption of new technologies (e.g., automated calf feeders, cow activity monitors, and automated milking systems) is accelerating. However, utilization of the data and action lists that these systems generate for health and welfare of livestock is still largely unrealized, and more training of dairy farmers, their employees, and their advisors is necessary. Concurrently, to remain competitive and to preserve their social license to operate, farmers are increasingly required to adopt increased standards for food safety and biosecurity, become less reliant on the use of antimicrobials and hormones, and provide assurances regarding animal welfare. Partly because of increasing herd size but also in response to animal welfare regulations in some countries, the proportion of dairy herds housed in tiestalls has decreased considerably. Although in some countries access to pasture is regulated, in countries that traditionally practiced seasonal grazing, fewer farmers let their dairy cows graze in the summer. The proportion of organic dairy farms has increased globally and, given the pressure to decrease the use of antimicrobials and hormones, conventional farms may be able to learn from well-managed organic farms. The possibilities of using milk for disease diagnostics and monitoring are considerable, and dairy herd improvement associations will continue to expand the number of tests offered to diagnose diseases and pregnancy. Genetic and genomic selection for increased resistance to disease offers substantial potential but requires collection of additional phenotypic data. There is every expectation that changes in the dairy industry will be further accentuated and additional novel technologies and different management practices will be adopted in the future.


Assuntos
Bem-Estar do Animal , Indústria de Laticínios/métodos , Agricultura Orgânica/métodos , Animais , Anti-Infecciosos/farmacologia , Bovinos , Doenças dos Bovinos/tratamento farmacológico , Doenças dos Bovinos/prevenção & controle , Resistência Microbiana a Medicamentos , Herbivoria , Hormônios/farmacologia , Leite/economia , Estações do Ano
7.
J Anim Sci ; 90(12): 4656-65, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22952364

RESUMO

Increased animal performance is suggested as one of the most effective mitigation strategies to decrease greenhouse gas (GHG) and ammonia (NH(3)) emissions from livestock production per unit of product produced. Little information exists, however, on the effects of increased animal productivity on the net decrease in emission from beef production systems. A partial life cycle assessment (LCA) was conducted using the Integrated Farm System Model (IFSM) to estimate GHG and NH(3) emissions from representative beef production systems in California that use various management technologies to enhance animal performance. The IFSM is a farm process model that simulates crop growth, feed production, animal performance, and manure production and handling through time to predict the performance, economics, and environmental impacts of production systems. The simulated beef production systems compared were 1) Angus-natural, with no use of growth-enhancing technologies, 2) Angus-implant, with ionophore and growth-promoting implant (e.g., estrogen/trenbolone acetate-based) application, 3) Angus-ß2-adrenergic agonists (BAA; e.g., zilpaterol), with ionophore, growth-promoting implant, and BAA application, 4) Holstein-implant, with growth implant and ionophore application, and 5) Holstein-BAA, with ionophore, growth implant, and BAA use. During the feedlot phase, use of BAA decreased NH(3) emission by 4 to 9 g/kg HCW, resulting in a 7% decrease in NH(3) loss from the full production system. Combined use of ionophore, growth implant, and BAA treatments decreased NH(3) emission from the full production system by 14 g/kg HCW, or 13%. The C footprint of beef was decreased by 2.2 kg carbon dioxide equivalent (CO(2)e)/kg HCW using all the growth-promoting technologies, and the Holstein beef footprint was decreased by 0.5 kg CO(2)e/kg HCW using BAA. Over the full production systems, these decreases were relatively small at 9% and 5% for Angus and Holstein beef, respectively. The growth-promoting technologies we evaluated are a cost-effective way to mitigate GHG and NH(3) emissions, but naturally managed cattle can bring a similar net return to Angus cattle treated with growth-promoting technologies when sold at an 8% greater premium price.


Assuntos
Amônia/química , Criação de Animais Domésticos/métodos , Pegada de Carbono , Substâncias de Crescimento/farmacologia , Carne/economia , Criação de Animais Domésticos/economia , Animais , California , Dióxido de Carbono/química , Dióxido de Carbono/metabolismo , Bovinos/fisiologia , Simulação por Computador , Efeito Estufa , Substâncias de Crescimento/administração & dosagem , Substâncias de Crescimento/economia , Hormônios/administração & dosagem , Hormônios/economia , Hormônios/farmacologia , Modelos Biológicos
8.
Rio de Janeiro; s.n; 2010. 127 p. tab, graf, ilus.
Tese em Português | LILACS | ID: lil-594526

RESUMO

A compulsão alimentar está associada a diversas doenças, entre elas, a obesidade. Com o intuito de pesquisar a diferença hormonal ligada ao controle da fome e da saciedade associada ao episódio de compulsão alimentar (ECA), avaliou-se a concentração sérica dos hormônios que regulam, este processo em mulheres adultas. Métodos: O estudo experimental foi composto de 3 grupos (n=23), sendo: grupo Eutrófico (GE;n=8), grupo obeso sem ECA (GO;n=7) e obesas com ECA (ECA;n=8). Todas as mulheres que participaram do estudo freqüentavam os serviços de saúde da Policlínica Piquet Carneiro. Foram dosados os hormônios: Grelina Total, Glucagon, Adiponectina, Amilina, Peptídeo C, GLP-1, Insulina e Leptina séricos nos tempos: jejum, 15 e 60 minutos após a ingestão da refeição fornecida. As refeições ingeridas foram controladas em energia, 55% carboidratos, 15% proteínas, 30% lipídios. Os dados foram analisados como valores médios por grupo em software SAS, considerando p<0,05. Resultados: A idade das mulheres estudadas variou de 32 a 50 anos. A concentração de adipon ectina encontrada, que é inversamente proporcional a adiposidade, foi significativamente menor no grupo ECA em relação aos demais grupos (P=0,01). Em relação à leptina, o grupo GO apresentou concentração maior em relação aos demais grupos (P<0,0001). Já, a concentração de grelina encontrada foi significativamente menor no grupo ECA em relação aos demais grupos (p=0,02). Foram encontradas concentrações significativamente maiores de insulina no grupo GO em relação aos demais grupos (p=0,04). A concentração de amilina encontrada foi significativamente maior no grupo GO em relação aos outros grupos (p=0,01). A concentração de GLP-1 encontrada no grupo GO foi maior em média, porém esta diferença não foi estatisticamente significativa entre os grupos (p=0,25). A concentração de Peptídeo C encontrada no grupo GO foi maior em relação aos outros grupos (p=0,003). Apesar da concentração de Glucagon no grupo ECA...


Binge eating is associated to several diseases, including obesity. In order to study the hormonal control of hunger and satiety that is commonly involved in binge-eating process: we evaluated the serum concentration of these hormones in adult women. Methods: The experimenal study was composed of 3 groups, n=23: Lean (GE, n=8), Obese without binge (GO, n=7) and obese with binge (BEE, n=8). All women who participated in the study attended the health services of the Polyclinic Piquet Carneiro. Serum hormones were assayed: total ghrelin, glucagon, adiponectin, Amylin, c-Peptide, glucagon like peptide (GLP-1), insulin and Leptin in fasting, 15 and 60 minutes after food intake. Meals were controlled in energy, 55% carbohidrates, 15% protein, 30% lipids. Data were analyzed as average values per group in SAS software, considering p<0.05. Results: Women's age ranged from 32 to 50 years. The adiponectin concentration, which is inversely proportional to adiposity, was significantly lower in BEE group than the other groups (p=0.01). Leptin of the GO group presented higher concentration than the others (p<0.0001). Ghrelin concentration was significantly lower in BEE group than the other groups (p=0.02). We found a significantly higher concentration of insulin in GO group in comparison to the others (p=0.04). Amylin concentration was significantly higher in GO group in comparison to the other groups (p=0.01). GLP-1 concentration of GO group was higher on average, but not statistically significant between groups (p=0.25). C-peptide concentration found in GO group was higher than the others (p=0.003). Despita glucagon concentration in the BEE group was greater than the other groups, these values were not statistically different (p=0.13). Conclusion: Our findings shown that BEE group have different hormonal profile than GO and GE. The lowest concentration of ghrelin found in BEE group and the hithest concentration of insulin, C-peptide and amylin found in both obese...


Assuntos
Humanos , Feminino , Comportamento Alimentar , Fome/fisiologia , Hormônios/análise , Hormônios/farmacologia , Obesidade/genética , Obesidade/metabolismo , Saciação , Resposta de Saciedade , Transtorno da Compulsão Alimentar/complicações , Transtorno da Compulsão Alimentar/diagnóstico , Grelina/deficiência
9.
J Comp Neurol ; 516(2): 117-24, 2009 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-19575447

RESUMO

Prairie voles (Microtus ochrogaster) are exceptional among rodents in that many aspects of their brain and behavior are not masculinized by exogenous aromatizable androgens. However, the sexually differentiated endpoints studied to date rely on estrogenic mechanisms in other mammals. We examined whether sexual differentiation of an androgen receptor-dependent sex difference would be similarly distinct in prairie voles. Male mammals have more and larger motoneurons projecting to perineal muscles than do females. This sex difference normally arises from males' perinatal androgen exposure and can be eliminated by treating developing females with androgens. Gross dissection revealed bulbospongiosus muscles in adult male, but not female, prairie voles. Retrograde tracing from males' bulbocavernosus muscles and the external anal sphincter from both sexes revealed sexually dimorphic populations of labeled motoneurons in the ventral horn of the lumbar spinal cord. Similar to other rodents, males had twice as many motoneurons as females, although no sex difference in motoneuron size was detected. Unexpectedly, prenatal or early postnatal exposure to testosterone propionate had no effect on adult females' motoneuron number or size. In adulthood, gonadectomy alone or followed by chronic testosterone treatment also had no effect on females' motoneuron size or number, although castration reduced motoneuron size in males. Comparing gonadally intact weanlings confirmed that the sex difference in motoneuron number exists before adulthood. As with some other sexually dimorphic traits, and perhaps related to their unique social organization, sexual differentiation of the prairie vole spinal cord differs from that found in most other laboratory rodents.


Assuntos
Arvicolinae/anatomia & histologia , Arvicolinae/metabolismo , Hormônios/metabolismo , Caracteres Sexuais , Medula Espinal/anatomia & histologia , Medula Espinal/metabolismo , Canal Anal/anatomia & histologia , Canal Anal/inervação , Animais , Animais Recém-Nascidos , Castração , Contagem de Células , Tamanho Celular/efeitos dos fármacos , Feminino , Hormônios/farmacologia , Masculino , Neurônios Motores/citologia , Neurônios Motores/efeitos dos fármacos , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/inervação , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Medula Espinal/efeitos dos fármacos , Testosterona/farmacologia , Propionato de Testosterona/farmacologia
10.
Neuroimmunomodulation ; 15(4-6): 351-64, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19047811

RESUMO

The continuous global increase in life expectancy represents a central challenge for our society and impacts public social security systems, families and individuals. One of the most striking changes that occur during normal human aging is immunosenescence, a progressive and overall diminution of immune functions that affect all cells and organs of the innate and adaptive immune system. As a hallmark of human aging, the progressive involution of the thymus leads to a disturbed balance and function of naïve, memory and effector T cells, thus promoting a latent pro-inflammatory status in the elderly. Together with chronic infections such as cytomegalovirus, that accumulate during life, this situation manifests in clinically relevant implications such as poor overall immune responses, decreased ability to control infectious disease and diminished response to vaccinations. Interestingly, this process parallels changes in the hormonal balance of aging subjects. In this review, we summarize recently published intriguing results from a very active and growing field of biomedical research and discuss some clinical consequences as well as possible ways of immune- and/or hormone-based interventions to delay or reverse immunosenescence.


Assuntos
Envelhecimento/imunologia , Sistema Imunitário/crescimento & desenvolvimento , Imunocompetência , Idoso , Idoso de 80 Anos ou mais , Animais , Atrofia , Linfócitos B/citologia , Linfócitos B/imunologia , Hormônios/farmacologia , Hormônios/fisiologia , Hormônios/uso terapêutico , Humanos , Imunidade Inata , Imunocompetência/efeitos dos fármacos , Longevidade/imunologia , Camundongos , Camundongos Transgênicos , Pessoa de Meia-Idade , Modelos Imunológicos , Neuroimunomodulação/fisiologia , Dinâmica Populacional , Subpopulações de Linfócitos T/citologia , Subpopulações de Linfócitos T/imunologia , Timo/patologia , Vacinação
11.
Int J Androl ; 26(4): 215-25, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12846797

RESUMO

Sertoli cell functional reserve was assessed in normozoospermic men and oligozoospermic patients and its prognostic potential was evaluated for patient selection and treatment. For the first objective, three groups of normo-follicle-stimulating hormone (FSH)/normozoospermic fertile men (n:12), normo-FSH/oligozoospermic (n:21) and hyper-FSH/oligozoospermic subfertile men participated in the study whereas for the second objective 24 normo-FSH oligozoospermic patients volunteered for a pilot therapeutic trial. For the first part, high purity (hp) FSH (225 i.u., i.m.), human chorionic gonadotropin (hCG) (1500 i.u., i.m.) or their combination was given separately at weekly intervals, with samplings at 0, 3, 24 and 48 h. For the pilot trial, rec-FSH (150 i.u./48 h, i.m.) or placebo were prescribed for 6 months. The main outcome measures for the study were inhibin-B (inh-B), insulin-like growth factor (IGF)-I, testosterone and oestradiol concentrations and the main sperm parameters. Bolus administration of hp-FSH or hp-FSH/hCG combination in normozoospermic men resulted in a significant rise of inh-B in normozoospermic men (mean +/- SD, basal: 183.8+/-24.2 pg/mL in hp-FSH and 175.2+/-23.5 in hp-FSH/hCG treatment; 48 h: 256.1+/-34.2 and 246.3+/-19.0, respectively, p<0.001 for both). In oligozoospermic groups basal inh-B concentration was lower than in normozoospermic men (normo-FSH: 117.4+/-16.5, hyper-FSH: 81.2+/-19.8, p<0.001 for both) with a post-stimulation increase noted only in normo-FSH patients (hp-FSH 24-h: 132.8+/-19.7, p<0.01; hp-FSH/hCG 0 min: 105.7+/-20.1, 24-h: 119.5+/-20.6, p<0.05). Total sperm number and progressive motility showed significant improvements (p<0.05 for both) after 6 months of rec-FSH treatment in the group of patients with a satisfactory response to hp-FSH stimulation. In conclusion, the basal and reserve activity of Sertoli cells, as judged by inh-B secretion, was higher in normozoospermic than in dyspermic men, with a better therapeutic outcome noted in those patients with an adequate response to hp-FSH stimulation.


Assuntos
Oligospermia/fisiopatologia , Células de Sertoli , Espermatozoides , Adulto , Estudos de Casos e Controles , Gonadotropina Coriônica/farmacologia , Combinação de Medicamentos , Estradiol/sangue , Hormônio Foliculoestimulante/sangue , Hormônio Foliculoestimulante/isolamento & purificação , Hormônio Foliculoestimulante/farmacologia , Hormônios/farmacologia , Humanos , Inibinas/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Pessoa de Meia-Idade , Oligospermia/sangue , Oligospermia/terapia , Projetos Piloto , Prognóstico , Estudos Prospectivos , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Espermatozoides/efeitos dos fármacos , Espermatozoides/fisiologia , Testosterona/sangue
12.
J Androl ; 19(3): 348-57, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9639052

RESUMO

Spermatogenesis in Asian men appears to be more susceptible to suppression by steroidal contraceptives administered in clinical trials than spermatogenesis in Caucasian men. The objective of this study was to determine whether ethnic differences exist in testicular structure and spermatogenic potential that might predispose Asians to a high sensitivity to steroidal contraceptives. Testes from 12 Chinese men were compared to those from 8 Hispanic men and 12 non-Hispanic Caucasian men of ages 29+/-3, 30+/-2, and 29+/-3 years, respectively. Testes were fixed by vascular perfusion with glutaraldehyde, further fixed in osmium, embedded in Epon, and evaluated by stereology using 0.5-microm sections stained with toluidine blue. Homogenates of fixed testes were evaluated for the number of Sertoli cells and the daily sperm production based on pachytene primary spermatocytes (PDSP) or spermatids with spherical nuclei (DSP). Paired parenchymal weight was less (P < 0.05) in Chinese men than in Hispanic or Caucasian men. The PDSP per gram of parenchyma was lower (P < 0.05) and the DSP per gram tended to be lower in Chinese men than in other groups. The histologic appearance, volume density, and length per man of seminiferous tubules were the same among the ethnic groups; however, the diameter of seminiferous tubules was less (P < 0.05) in Chinese than in Hispanic or Caucasian men. The PDSP per man and the DSP per man were lower (P < 0.05) in Chinese than in Hispanic or Caucasian men. The number of Sertoli cells per gram was higher (P < 0.05) in Chinese or Caucasian men than in Hispanic men, but the number of Sertoli cells per man was lower (P < 0.05) in Chinese men than in Hispanic or Caucasian men. Sertoli cell function, measured as the number of germ cells accommodated by a single Sertoli cell, was lower (P < 0.05) in Chinese men than in Caucasian men. The volume density of Leydig cell cytoplasm was greatest (P < 0.05) in Chinese men, but the number of Leydig cells was similar among the ethnic groups. Hence, smaller testes coupled with reduced Sertoli cell number and function and reduced daily sperm production could predispose Asian men to have a heightened negative response of testes to steroidal contraceptives, as compared to Caucasian men. Dampening (by exogenous androgens) of any physiological benefit to spermatogenesis that a high volume density of Leydig cell cytoplasm may bestow on the human testis (that Asian men may have evolved to require) would exacerbate ethnic differences in the spermatogenic response to hormonal contraceptives.


PIP: Multicenter studies conducted by the World Health Organization suggest that the efficacy of spermatogenesis suppression by hormonal contraception differs across racial and ethnic groups. For both androgens alone and androgens in combination with a progestin, the suppression of spermatogenesis to persistent azoospermia occurred in about 90% of Asian men compared to 60-70% of Caucasians. The present study investigated ethnic differences in testicular structure that may affect the sensitivity of the testis to gonadotropin suppression and the spermatogenic potential of the testis. Testes of 12 healthy Asian men from China who died of sudden traumatic injuries and of 8 Hispanic and 12 Caucasian men from the US who died of the same cause were obtained at autopsy and analyzed. Both paired testicular weight and paired testicular parenchymal weight were significantly lower in Chinese men than Hispanic or Caucasian men. Pachytene primary spermatocytes per gram of parenchyma and spermatids with spherical nuclei also were lower in Chinese men than in the other groups. The histologic appearance, volume density, and length per man of seminiferous tubules were the same across ethnic groups, but the volume of seminiferous tubules per man was significantly lower in Chinese men. The number of Sertoli cells per gram was significantly higher in Chinese and Caucasian men than in Hispanic men, but the number of Sertoli cells per man and Sertoli cell function were significantly lower in Chinese men than the other two groups. The volume density of Leydig cell cytoplasm was greater in Chinese men, but the number of Leydig cells was similar across groups. It is postulated that smaller testes, coupled with the reduced number and function of Sertoli cells and reduced daily sperm production, contribute to an inherently lower spermatogenic potential in Asian men, which predisposes them to a heightened negative spermatogenic response to steroidal contraceptives.


Assuntos
Povo Asiático , Anticoncepcionais Masculinos/farmacologia , Hormônios/farmacologia , Espermatogênese/efeitos dos fármacos , Testículo/efeitos dos fármacos , Adulto , China , Hispânico ou Latino , Humanos , Células Intersticiais do Testículo/citologia , Células Intersticiais do Testículo/efeitos dos fármacos , Masculino , Células de Sertoli/citologia , Células de Sertoli/efeitos dos fármacos , Espermatogênese/fisiologia , Testículo/fisiologia , População Branca
13.
Br J Clin Pharmacol ; 45(5): 463-9, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9643619

RESUMO

AIMS: To provide methods for the translation of the concentration-time profile of highly cleared marker compounds into the underlying clearance and hepatic blood flow profile. METHODS: Continuous infusion of indocyanine green or sorbitol was used to assess the effect of the hepatic blood flow modifiers exercise, somatostatin and octreotide. Three distinct methods are described for the translation of concentration into flow: 1. assuming successive phases of constant clearance 2. point to point estimation of clearance using estimates of concentration change 3. using a parametric description of the flow profile in combination with the differential equations describing the change in marker concentrations. RESULTS: The marker compound concentration profiles are adequately described using the different methods. Exercise results in a decrease in hepatic blood flow of about 80%. Somatostatin and octreotide elicit an indistinguishable hepatic blood flow decrease from 1.49 to 1.07 l min(-1). Return to baseline takes much longer for octreotide (half-life 126+/-104 min) than for somatostatin (half-life 4.29+/-3.55 min). CONCLUSIONS: Translation of concentration profiles into clearance profiles is possible making continuous assessment of hepatic blood flow feasible.


Assuntos
Exercício Físico/fisiologia , Antagonistas de Hormônios/farmacologia , Hormônios/farmacologia , Circulação Hepática , Octreotida/farmacologia , Somatostatina/farmacologia , Corantes/administração & dosagem , Corantes/farmacocinética , Meia-Vida , Antagonistas de Hormônios/farmacocinética , Hormônios/farmacocinética , Humanos , Indicadores e Reagentes/administração & dosagem , Indicadores e Reagentes/farmacocinética , Verde de Indocianina/administração & dosagem , Verde de Indocianina/farmacocinética , Infusões Intravenosas , Circulação Hepática/efeitos dos fármacos , Taxa de Depuração Metabólica , Modelos Biológicos , Octreotida/farmacocinética , Somatostatina/farmacocinética , Sorbitol/administração & dosagem , Sorbitol/farmacocinética
15.
Obstet Gynecol ; 78(2): 187-90, 1991 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1906152

RESUMO

Problems arising from controlled ovarian hyperstimulation for intrauterine insemination, such as premature luteinization and asynchronous ovarian follicular development, are identical to those encountered with controlled ovarian hyperstimulation for in vitro fertilization (IVF) and gamete intrafallopian transfer (GIFT). It has been suggested that the adjunctive use of GnRH agonists for controlled ovarian hyperstimulation improves the efficiency of GIFT and IVF cycles. We hypothesized that adjunctive use of leuprolide acetate, a GnRH agonist, would have a similarly beneficial effect on cycle quality and cycle fecundity in subfertile women treated with controlled ovarian hyperstimulation and intrauterine insemination. We randomly assigned the first cycle of controlled ovarian hyperstimulation and intrauterine insemination for each of 97 subfertile women to include either human menopausal gonadotropins (hMGs) alone or hMGs following midluteal pre-treatment with leuprolide. If a pregnancy did not occur in the first cycle, the woman was given the other treatment in the second cycle. Although the cycles that included leuprolide required a larger amount of hMGs and more days of stimulation per cycle, the mean estradiol concentrations and numbers of follicles were not different. Despite prevention of premature luteinization with leuprolide, the cycle fecundity was not different between groups (0.11 with adjunctive leuprolide treatment and 0.22 with hMGs alone). We conclude that in unselected subfertile patients, the adjunctive use of leuprolide for controlled ovarian hyperstimulation and intrauterine insemination does not improve cycle fecundity compared with treatment cycles that do not include adjunctive leuprolide therapy.


Assuntos
Fertilidade/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/análogos & derivados , Hormônios/uso terapêutico , Infertilidade Feminina/tratamento farmacológico , Inseminação Artificial , Menotropinas/uso terapêutico , Indução da Ovulação/métodos , Adulto , Quimioterapia Combinada , Feminino , Hormônio Liberador de Gonadotropina/farmacologia , Hormônio Liberador de Gonadotropina/uso terapêutico , Hormônios/farmacologia , Humanos , Infertilidade Feminina/economia , Leuprolida , Menotropinas/farmacologia , Ciclo Menstrual/efeitos dos fármacos , Ovário/efeitos dos fármacos
17.
Hastings Cent Rep ; 14(2): 5-9, 1984 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-6724884

RESUMO

KIE: The impending Food and Drug Administration approval of a synthetic growth hormone (hGH) for use with children deficient in the hormone is expected to present a dilemma for physicians confronted by parental demands for hGH treatment of normal, but short, children. Little is known of long term effects of such treatment, which is protracted, slow to yield results, costly, and likely to cause psychological problems when ineffective. Public policy concerns include treating normal people to attain an ideal goal, equity in distribution of a costly treatment, reinforcement of "heightism," and the justifiability of clinical research on non-hGH deficient children.^ieng


Assuntos
Estatura/efeitos dos fármacos , Ética Médica , Hormônio do Crescimento/farmacologia , Saúde , Hormônios/farmacologia , Medição de Risco , Desenvolvimento Ósseo/efeitos dos fármacos , Criança , Feminino , Doenças Genéticas Inatas , Transtornos do Crescimento/etiologia , Transtornos do Crescimento/psicologia , Hormônio do Crescimento/deficiência , Humanos , Masculino , Obrigações Morais , Seleção de Pacientes , Pediatria , Papel do Médico , Estados Unidos
18.
Maturitas ; 3(3-4): 265-9, 1981 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6801438

RESUMO

Using a 24-h whole-body retention (WBR) of Tc99m hydroxyethylidene diphosphonate (HEDP), a sensitive measure of skeletal metabolism, 24 women receiving the synthetic steroid hormone Org OD 14 were studied. OD 14 was found to have a powerful suppressive effect on skeletal metabolism in both oophorectomized and non-oophorectomized women when compared with control subjects (P less than 0.001 and P less than 0.01, respectively). The degree of suppression was similar to that found with oestrogen therapy. While it has previously been shown that OD 14 prevents bone mineral loss (as measured by photon-absorptiometry), the present study provides further evidence as to the efficacy of this compound in suppressing skeletal metabolism.


Assuntos
Anabolizantes/farmacologia , Osso e Ossos/metabolismo , Hormônios/farmacologia , Norpregnenos/farmacologia , Compostos de Organotecnécio , Fosfatase Alcalina/sangue , Osso e Ossos/efeitos dos fármacos , Cálcio/sangue , Castração , Ácido Etidrônico , Feminino , Humanos , Pessoa de Meia-Idade , Minerais/metabolismo , Hormônio Paratireóideo/sangue , Tecnécio , Contagem Corporal Total
19.
Circulation ; 62(4 Pt 2): IV24-30, 1980 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7188560

RESUMO

We investigated the association of plasma high-density lipoprotein (HDL) cholesterol levels with levels of cholesterol in other plasma lipoprotein fractions (low-density [LDL], very low density [VLDL] and their sum) and with total plasma cholesterol and triglyceride levels in 3493 males and 3318 females in the Lipid Research Clinics (LRC) Prevalence Study. Correlation coefficients were calculated for each stratum of age, sex and hormone use using a logarithmic transformation. The correlations of log HDL cholesterol with the other lipid and lipoprotein fractions generally depended strongly on age and sex but not on use of gonadal hormones. In the 20-70-year range, the age dependence of each correlation coefficient was well described by a linear regression model. The weakly positive association between HDL and total cholesterol levels in adults and the marked negative association of HDL cholesterol with triglyceride and VLDL cholesterol levels in almost all strata are in good general agreement with the results of earlier studies.


Assuntos
Colesterol/sangue , Lipídeos/sangue , Lipoproteínas HDL/sangue , Lipoproteínas/sangue , Adolescente , Adulto , Idoso , Arteriosclerose/diagnóstico , Criança , Pré-Escolar , Feminino , Hormônios/farmacologia , Humanos , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Fatores Socioeconômicos , Triglicerídeos/sangue
20.
Z Tierpsychol ; 44(1): 1-12, 1977 May.
Artigo em Inglês | MEDLINE | ID: mdl-562565

RESUMO

In order to ascertain whether hormones influence social organization of lizards, caged Sphenomorphus kosciuskoi were studied both before and after treatment with testosterone, estradiol, adrenaline and thyroxine. Testosterone and estradiol increased aggressiveness in male lizards and caused shifts in dominance. Adrenaline caused a temporary increase in activity and agressiveness but no change in social structure. Thyroxine did not affect social behaviour.


Assuntos
Agressão/efeitos dos fármacos , Hormônios/farmacologia , Lagartos , Animais , Comportamento Animal/efeitos dos fármacos , Epinefrina/farmacologia , Estradiol/farmacologia , Feminino , Humanos , Masculino , Comportamento Social , Predomínio Social , Testosterona/farmacologia , Tiroxina/farmacologia
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