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1.
Endocrine ; 31(2): 202-11, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17873333

RESUMO

The serotonin (5HT) reuptake transporter (SERT) plays a key role in 5HT homeostasis by recycling 5HT into the presynaptic neurons. Recently, polymorphisms in the length of the promoter region of the gene that encodes SERT have been linked to functional differences in reactivity to psychosocial stress, as the short (s) promoter length allele shows reduced transcriptionally activity in vitro and is associated with reduced 5HT activity and increased vulnerability to affective disorders. Given 5HT's important role in appetite regulation, polymorphisms in the SERT gene could also affect metabolic parameters. In addition, since reduced 5HT activity may also predispose females to reproductive deficits, polymorphisms in the SERT gene may help explain individual differences in ovulatory function. The present study, using a rhesus monkey model, tested the hypothesis that the presence of the s-variant allele would be associated with altered metabolic regulation and impaired ovulatory cycles compared with the l/l genotype. Females homozygous for the long allele in the SERT gene (l/l, n = 19) were compared to those with the s-variant allele (l/s or s/s, n = 20). All females had similar social histories. Body weights (P = 0.026) but not heights (P = 0.618) were significantly lower in s-variant compared to l/l females. In addition, both BMI (P = 0.032) and sagittal abdominal diameters (SAD) (P = 0.031), as indices of adiposity, were significantly lower in s-variant females. Consistent with these differences, fasting and non-fasting levels of leptin were significantly lower in s-variant females (P = 0.002). While there were no genotype differences in non-fasting levels of insulin, s-variant females had significantly lower concentrations of insulin during a fast than did l/l females (P = 0.052). Neither glucose, T 3, T 4, nor ghrelin varied significantly between groups during either the fasted or non-fasted condition (P > 0.05). Analysis of a subset of females indicated that significantly fewer s-variant females (62.5%) exhibited ovulatory cycles than l/l females (100%, P < 0.05). However, there were no differences in serum estradiol or progesterone in l/l females and those s-variant females that did ovulate (P > 0.05). In addition, females with the s-variant genotype also had reduced 5HT activity (P = 0.030), assessed from the acute increase in serum prolactin following the administration of the 5HT reuptake inhibitor, citalopram. Finally, s-variant females were significantly less responsive to glucocorticoid negative feedback (P = 0.030) yet more responsive to corticotropin releasing hormone (CRH, P = 0.016) in terms of plasma cortisol than were l/l females. These data indicate that adult female rhesus monkeys with the s-variant polymorphism in the SERT gene exhibit metabolic and reproductive alterations in conjunction with reduced serotonergic responsivity and increased LHPA activity and suggest the possibility that this genotype may predispose females exposed to psychosocial stressors to further metabolic and reproductive deficits.


Assuntos
Macaca mulatta/genética , Macaca mulatta/metabolismo , Polimorfismo de Nucleotídeo Único , Reprodução/genética , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Animais , Glicemia/análise , Retroalimentação Fisiológica , Feminino , Grelina , Glucocorticoides/metabolismo , Insulina/sangue , Leptina/sangue , Macaca mulatta/sangue , Metabolismo/genética , Ovulação/genética , Ovulação/fisiologia , Hormônios Peptídicos/sangue , Prolactina/sangue , Serotonina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Hormônios Tireóideos/sangue
2.
Poult Sci ; 86(5): 944-52, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17435030

RESUMO

The characterization of the follicular hierarchy and the expression of the mRNA for the inhibin/activin subunits was investigated in the follicles of 2 lines of turkey hens selected for over 40 generations for increased egg production (Egg line) or increased body weight (Growth line). The follicular hierarchies of 6 hens from the Egg and Growth lines were characterized in middle (45 wk of age) and late production (58 wk of age). Relative follicular weights for individual hierarchical follicles (>12 mm), pooled small yellow follicles (5 to 12 mm), and large white follicles (2 to 5 mm) were calculated. Total RNA was extracted for Northern blot analysis from individual granulosa cell layers of the F1 through F4 follicles, and from the combined granulosa and theca layers of small yellow follicles and large white follicles from an additional 6 hens from each genetic line. Egg line hens displayed a more distinct follicular size hierarchy than Growth line hens at 45 and 58 wk. Although total follicular weight relative to body size was greater at 45 and 58 wk of age for the Egg line hens than the Growth line hens, the total number of hierarchical follicles was greater in the Growth line hens at 45 and 58 wk of age. Expression of follistatin and the inhibin beta(B)-subunit was highest in nonhierarchical follicles, whereas the expression of the inhibin alpha- and beta(A)-subunits was highest in the hierarchical follicles. The inhibin alpha- and beta(A)-subunit mRNA expression pattern in the 4 largest follicles of the Growth line hens was not similar to the Egg line hens or characteristic of laying hens that have a high rate of egg production. The unusual inhibin subunit mRNA expression in the largest hierarchical follicles of the Growth line hens may account for their development of an abnormal follicular size hierarchy and for their poor egg production.


Assuntos
Ativinas/genética , Regulação da Expressão Gênica , Inibinas/genética , Folículo Ovariano/metabolismo , Oviposição/genética , Perus/genética , Perus/metabolismo , Animais , Feminino , Folistatina/genética , Folistatina/metabolismo , Oviposição/fisiologia , Probucol/análogos & derivados , Subunidades Proteicas/metabolismo , RNA Mensageiro
3.
Bioorg Med Chem Lett ; 11(7): 915-8, 2001 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-11294390

RESUMO

The serine protease urokinase (uPa) has been implicated in the progression of both breast and prostate cancer. Utilizing structure based design, the synthesis of a series of substituted 4-[2-amino-1,3-thiazolyl]-thiophene-2-carboxamidines is described. Further optimization of this series by substitution of the terminal amine yielded urokinase inhibitors with excellent activities.


Assuntos
Amidinas/síntese química , Amidinas/farmacologia , Ativadores de Plasminogênio/antagonistas & inibidores , Tiazóis/farmacologia , Ativador de Plasminogênio Tipo Uroquinase/antagonistas & inibidores , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos , Relação Estrutura-Atividade , Tiazóis/síntese química , Tiofenos/síntese química , Tiofenos/farmacologia
4.
Child Adolesc Psychiatr Clin N Am ; 9(3): 647-61, ix, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10944660

RESUMO

Children with attention-deficit/hyperactivity disorder (ADHD) are at risk for impaired functioning in most areas related to school success. Despite the benefits of psychostimulants and other medications to alleviate problem behaviors associated with ADHD, these therapies are unable to completely ameliorate behavior problems for all children with this disorder. Additionally, whereas pharmacologic therapies do impact behavioral functioning they have not been shown to improve academic achievement. Therefore, attention needs to be directed toward psychoeducational interventions and their ability to increase the successful functioning of children with ADHD. The purpose of this article is to highlight some of the most prominent and empirically validated classroom intervention strategies for children with ADHD. Additionally, this article discusses the importance of choosing psychoeducational interventions based on functional assessment data. Finally, this article describes progress monitoring strategies that should be used to determine the efficacy of intervention strategies.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/prevenção & controle , Adolescente , Terapia Comportamental , Criança , Instrução por Computador , Humanos , Grupo Associado
6.
J Med Chem ; 35(21): 3905-18, 1992 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-1331448

RESUMO

A new structural class of cyclic hexapeptide oxytocin antagonists derived from Streptomyces silvensis and typified by L-365,209 (cyclo-[L-prolyl1-D-phenylalanyl2-L- isoleucyl3-D-dehydropiperazyl4-L-dehydroperazyl5-D-(N- methyl)phenylalanyl6]) was recently reported. In this paper we further delineate the structure-activity profile for this new class by systematic study of L-365,209 analogs obtained by total synthesis. The optimal combination of cyclic amino acid ring sizes at positions 1, 4, and 5 and the role of the N-alkyl substituent at position 6 was elucidated. The lipophilic amino acids at positions 2 and 3 and the unusual amino acid D-dehydropiperazic acid at position 4 were found to be the most critical residues for obtaining good oxytocin receptor affinity. Analogs containing a basic side chain at the less critical 5- and 6-positions maintained good receptor affinity and also had useful levels of water solubility for intravenous formulation. By combining potency- and solubility-enhancing substitutions, several analogs were identified that have the desired combination of properties in vitro (22, cyclo-[L-prolyl-D-tryptophanyl-L-isoleucyl-D-pipecolyl-L-pipeco lyl-D- histidyl]; 25, cyclo-[L-prolyl-D-2-naphthylalanyl-L-isoleucyl-D-pipecolyl-L -pipecolyl-D- histidyl]; 26, cyclo-[L-prolyl-D-tryptophanyl-L-isoleucyl-D-dehydropiperazyl-L-++ pipecolyl-D-histidyl]; 33, cyclo-[L-prolyl-D-tryptophanyl-L-isoleucyl-D-pipecolyl-L- piperazinylcarboxy-D-(N-methyl)phenylalanyl]; 34, cyclo-[L-prolyl-D-phenylalanyl-L-isoleucyl-D-dehydropiperazyl-L-or nithyl- D-(N-methyl)phenylalanyl]). In general, this class exhibited good selectivity for binding to the oxytocin receptor versus the arginine vasopressin V1a and V2 receptor subtypes, although increased V2 receptor affinity was observed in one case (32, cyclo[L-prolyl-D-2-naphthylalanyl-L-isoleucyl-D-pipecolyl-L- lysyl-D-(N- methyl)phenylalanyl]). Unexpectedly, compound 33 was found to stimulate contractions of the isolated rat uterus via activation of the uterine bradykinin receptor. Compounds 22, 25, 26, 33, and 34 were found to be potent antagonists of oxytocin-stimulated contraction of the rat uterus in vitro and in vivo. Compounds 22 and 25 were additionally characterized as potent antagonists of oxytocin-stimulated uterine contractions in the near-term pregnant rhesus monkey. These studies thus demonstrate the selectivity and efficacy of certain members of this novel class of antagonists and suggest their use as pharmacological tools in further defining the role of oxytocin in both term and preterm labor.


Assuntos
Ocitocina/antagonistas & inibidores , Peptídeos Cíclicos/farmacologia , Sequência de Aminoácidos , Animais , Feminino , Haplorrinos , Técnicas In Vitro , Masculino , Dados de Sequência Molecular , Ocitocina/metabolismo , Peptídeos Cíclicos/química , Ensaio Radioligante , Ratos , Receptores de Angiotensina/metabolismo , Receptores de Ocitocina , Streptomyces/metabolismo , Relação Estrutura-Atividade , Especificidade por Substrato
7.
West J Med ; 126(1): 83, 1977 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18747877
8.
West J Med ; 125(6): 430, 1976 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18747834
9.
West J Med ; 125(6): 451, 1976 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18747836
10.
West J Med ; 125(5): 406, 1976 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18747828
11.
West J Med ; 125(5): 414, 1976 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18747830
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