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1.
J Community Health ; 45(5): 965-972, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32306182

RESUMO

Physical activity (PA) and nutrition behaviors among college students in health-related disciplines are understudied. We used theory of planned behavior (TPB) and role model beliefs (RMB) to predict PA and eating behaviors of college students in health-related programs (nurses, physical education, exercise science, and athletic training). A 26-item survey was administered among the participants. Independent variables included TPB constructs and RMB measured on a 5-point scale. PA was measured by multiplicative scores of students' number of days by the amount of time spent exercising per week. Nutrition behavior was measured using fruits (2½ c-eq/day), vegetables (2½ c-eq/day), dairy (2 c-eq/day), grains (6 oz-eq/day), and proteins (5½ oz-eq/day). Multiple regression analyses were used to predict PA and nutrition behaviors. A total of 271 college health majors (mean age 22.5 ± 4.6 years) participated in the study. The majority (56.8%) of students did not meet the weekly PA guidelines and 43.2% did not meet the recommended dietary guidelines for daily servings of food groups combined. Regression analyses showed that outcome evaluation, behavioral belief, and RMB, were significantly related with student's PA behavior and they accounted for 34%, 8%, and 1% of the variance, respectively (total R2 = 44.7). Outcome evaluation and behavioral beliefs were significantly related with nutritional behavior and they accounted for 13.3%, and 5.3% of the variance respectively (total R2 = 18.6). TPB (outcome evaluation, behavioral belief) and RMB could be used to guide programs in promoting PA and nutrition behavior among college health majors.


Assuntos
Exercício Físico , Comportamento Alimentar , Comportamentos Relacionados com a Saúde , Promoção da Saúde , Estado Nutricional , Adolescente , Adulto , Feminino , Frutas , Humanos , Masculino , Política Nutricional , Teoria Psicológica , Estudantes , Inquéritos e Questionários , Verduras , Adulto Jovem
2.
Clin Pharmacol Ther ; 103(2): 341-348, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28543042

RESUMO

Myrcludex B acts as a hepatitis B and D virus entry inhibitor blocking the sodium taurocholate cotransporting polypeptide (SLC10A1). We investigated the effects of myrcludex B on plasma bile acid disposition, tenofovir pharmacokinetics, and perpetrator characteristics on cytochrome P450 (CYP) 3A. Twelve healthy volunteers received 300 mg tenofovir disoproxil fumarate orally and 10 mg subcutaneous myrcludex B. Myrcludex B increased total plasma bile acid exposure 19.2-fold without signs of cholestasis. The rise in conjugated bile acids was up to 124-fold (taurocholic acid). Coadministration of tenofovir with myrcludex B revealed no relevant changes in tenofovir pharmacokinetics. CYP3A activity slightly but significantly decreased by 29% during combination therapy. Myrcludex B caused an asymptomatic but distinct rise in plasma bile acid concentrations and had no relevant impact on tenofovir pharmacokinetics. Changes in CYP3A activity might be due to alterations in bile acid signaling. Long-term effects of elevated bile acids will require critical evaluation.


Assuntos
Antivirais/administração & dosagem , Ácidos e Sais Biliares/sangue , Lipopeptídeos/administração & dosagem , Inibidores da Transcriptase Reversa/farmacocinética , Tenofovir/farmacocinética , Administração Oral , Adulto , Antivirais/efeitos adversos , Antivirais/farmacocinética , Biomarcadores/sangue , Citocromo P-450 CYP3A/metabolismo , Interações Medicamentosas , Feminino , Humanos , Injeções Subcutâneas , Lipopeptídeos/efeitos adversos , Lipopeptídeos/farmacocinética , Masculino , Pessoa de Meia-Idade , Transportadores de Ânions Orgânicos Dependentes de Sódio/antagonistas & inibidores , Transportadores de Ânions Orgânicos Dependentes de Sódio/metabolismo , Estudos Prospectivos , Inibidores da Transcriptase Reversa/administração & dosagem , Inibidores da Transcriptase Reversa/efeitos adversos , Medição de Risco , Simportadores/antagonistas & inibidores , Simportadores/metabolismo , Tenofovir/administração & dosagem , Tenofovir/efeitos adversos , Regulação para Cima , Adulto Jovem
3.
Adv Pharmacol ; 77: 307-60, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27451102

RESUMO

In premenopausal women, endogenous estrogens are associated with reduced prevalence of arterial hypertension, coronary artery disease, myocardial infarction, and stroke. Clinical trials conducted in the 1990s such as HERS, WHI, and WISDOM have shown that postmenopausal treatment with horse hormone mixtures (so-called conjugated equine estrogens) and synthetic progestins adversely affects female cardiovascular health. Our understanding of rapid (nongenomic) and chronic (genomic) estrogen signaling has since advanced considerably, including identification of a new G protein-coupled estrogen receptor (GPER), which like the "classical" receptors ERα and ERß is highly abundant in the cardiovascular system. Here, we discuss the role of estrogen receptors in the pathogenesis of coronary artery disease and review natural and synthetic ligands of estrogen receptors as well as their effects in physiology, on cardiovascular risk factors, and atherosclerotic vascular disease. Data from preclinical and clinical studies using nonselective compounds activating GPER, which include selective estrogen receptor modulators such as tamoxifen or raloxifene, selective estrogen receptor downregulators such as Faslodex™ (fulvestrant/ICI 182,780), vitamin B3 (niacin), green tea catechins, and soy flavonoids such as genistein or resveratrol, strongly suggest that activation of GPER may afford therapeutic benefit for primary and secondary prevention in patients with or at risk for coronary artery disease. Evidence from preclinical studies suggest similar efficacy profiles for selective small molecule GPER agonists such as G-1 which are devoid of uterotrophic activity. Further clinical research in this area is warranted to provide opportunities for future cardiovascular drug development.


Assuntos
Doença da Artéria Coronariana/tratamento farmacológico , Estrogênios/metabolismo , Receptores de Estrogênio/metabolismo , Animais , Doenças Cardiovasculares/prevenção & controle , Feminino , Humanos , Ligantes , Fatores de Risco , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Transdução de Sinais/efeitos dos fármacos
4.
Food Chem ; 136(1): 87-93, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23017396

RESUMO

Common bean (Phaseolus vulgaris L.), the staple crop of Nicaragua, provides protein and nonhaem iron, but inhibitors such as phytate may prevent absorption of iron and zinc by the consumer. Warehouses in Nicaragua do not have controlled atmospheres, so beans are exposed to high temperatures and humidities that may accelerate quality loss. To evaluate the impact of 6months of storage on quality, four national accessions of common bean were submitted to two treatments, a conventional warehouse with uncontrolled temperature and humidity, and accelerated ageing at 40°C and 75% RH. Iron content was 61-81mg/kg of which 3-4% was bioavailable, and zinc content was 21-25mg/kg, of which 10-12% was bioavailable. Bioavailability generally increased in storage, significantly so in year-old INTA Linea 628 in accelerated ageing. The concentration of phytate was 8.6-9.6mg/g and it contained 54-63% of the total phosphorus. Improvement in bioavailability of divalent cations is needed.


Assuntos
Armazenamento de Alimentos/métodos , Ferro/análise , Phaseolus/química , Ácido Fítico/farmacologia , Sementes/química , Zinco/análise , Absorção/efeitos dos fármacos , Disponibilidade Biológica , Humanos , Umidade , Nicarágua , Phaseolus/metabolismo , Sementes/metabolismo , Temperatura , Zinco/metabolismo
5.
Acta Physiol (Oxf) ; 203(1): 259-69, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21281456

RESUMO

Obesity increases the risk of coronary artery disease through insulin resistance, diabetes, arterial hypertension and dyslipidemia. The prevalence of obesity has increased worldwide and is particularly high among middle-aged women and men. After menopause, women are at an increased risk to develop visceral obesity due to the loss of endogenous ovarian hormone production. Effects of oestrogens are classically mediated by the two nuclear oestrogen receptors (ERs) α and ß. In addition, more recent research has shown that the intracellular transmembrane G-protein-coupled oestrogen receptor (GPER) originally designated as GPR30 also mediates some of the actions attributed to oestrogens. Oestrogen and its receptors are important regulators of body weight and insulin sensitivity not only in women but also in men as demonstrated by ER mutations in rodents and humans. This article reviews the role of sex hormones and ERs in the context of obesity, insulin sensitivity and diabetes as well as the related clinical issues in women and men.


Assuntos
Diabetes Mellitus Tipo 2/etiologia , Resistência à Insulina/fisiologia , Obesidade/complicações , Receptores de Estrogênio/metabolismo , Caracteres Sexuais , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/fisiopatologia , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/fisiopatologia , Estrogênios/metabolismo , Feminino , Humanos , Masculino , Obesidade/metabolismo , Obesidade/fisiopatologia
6.
Praxis (Bern 1994) ; 97(21): 1137-41, 2008 Oct 22.
Artigo em Alemão | MEDLINE | ID: mdl-18951354

RESUMO

A 65-year-old architect was admitted to our Memory Clinic because of rapidly progressive dementia accompanied by behavioral disorders, which severely restricted his functional independence. The physical examination revealed several focal neurological signs, and neuroimaging confirmed a cerebellar hemorrhage, multiple microbleeds and an ischemic lacunar infarct. Executive functioning was highly impaired. This case report illustrates cerebral amyloid angiopathy as an important entity of vascular dementia and highlights the importance of neuroimaging in patients with suspected vascular cognitive disorders.


Assuntos
CADASIL/complicações , Demência Vascular/etiologia , Transtornos Mentais/etiologia , Idoso , CADASIL/diagnóstico , Hemorragia Cerebral/diagnóstico , Hemorragia Cerebral/etiologia , Infarto Cerebral/diagnóstico , Infarto Cerebral/etiologia , Demência Vascular/diagnóstico , Diagnóstico Diferencial , Progressão da Doença , Humanos , Imageamento por Ressonância Magnética , Masculino , Transtornos Mentais/diagnóstico , Entrevista Psiquiátrica Padronizada
7.
Mol Cell Biol ; 21(13): 4347-68, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11390663

RESUMO

Starvation for amino acids induces Gcn4p, a transcriptional activator of amino acid biosynthetic genes in Saccharomyces cerevisiae. In an effort to identify all genes regulated by Gcn4p during amino acid starvation, we performed cDNA microarray analysis. Data from 21 pairs of hybridization experiments using two different strains derived from S288c revealed that more than 1,000 genes were induced, and a similar number were repressed, by a factor of 2 or more in response to histidine starvation imposed by 3-aminotriazole (3AT). Profiling of a gcn4Delta strain and a constitutively induced mutant showed that Gcn4p is required for the full induction by 3AT of at least 539 genes, termed Gcn4p targets. Genes in every amino acid biosynthetic pathway except cysteine and genes encoding amino acid precursors, vitamin biosynthetic enzymes, peroxisomal components, mitochondrial carrier proteins, and autophagy proteins were all identified as Gcn4p targets. Unexpectedly, genes involved in amino acid biosynthesis represent only a quarter of the Gcn4p target genes. Gcn4p also activates genes involved in glycogen homeostasis, and mutant analysis showed that Gcn4p suppresses glycogen levels in amino acid-starved cells. Numerous genes encoding protein kinases and transcription factors were identified as targets, suggesting that Gcn4p is a master regulator of gene expression. Interestingly, expression profiles for 3AT and the alkylating agent methyl methanesulfonate (MMS) overlapped extensively, and MMS induced GCN4 translation. Thus, the broad transcriptional response evoked by Gcn4p is produced by diverse stress conditions. Finally, profiling of a gcn4Delta mutant uncovered an alternative induction pathway operating at many Gcn4p target genes in histidine-starved cells.


Assuntos
Aminoácidos/biossíntese , Proteínas de Ligação a DNA/metabolismo , Proteínas Fúngicas/metabolismo , Perfilação da Expressão Gênica , Regulação Fúngica da Expressão Gênica/genética , Proteínas Quinases/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Aminoácidos/genética , Amitrol (Herbicida)/farmacologia , Proteínas de Ligação a DNA/genética , Proteínas Fúngicas/genética , Genes Reporter/genética , Glicogênio/metabolismo , Metanossulfonato de Metila/farmacologia , Mitocôndrias/genética , Mitocôndrias/metabolismo , Modelos Teóricos , Mutagênicos/farmacologia , Análise de Sequência com Séries de Oligonucleotídeos , Peroxissomos/genética , Peroxissomos/metabolismo , Regiões Promotoras Genéticas/genética , Proteínas Quinases/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Saccharomyces cerevisiae/fisiologia , Transativadores/genética , Transativadores/metabolismo
8.
Nat Biotechnol ; 19(4): 342-7, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11283592

RESUMO

We describe a flexible system for gene expression profiling using arrays of tens of thousands of oligonucleotides synthesized in situ by an ink-jet printing method employing standard phosphoramidite chemistry. We have characterized the dependence of hybridization specificity and sensitivity on parameters including oligonucleotide length, hybridization stringency, sequence identity, sample abundance, and sample preparation method. We find that 60-mer oligonucleotides reliably detect transcript ratios at one copy per cell in complex biological samples, and that ink-jet arrays are compatible with several different sample amplification and labeling techniques. Furthermore, results using only a single carefully selected oligonucleotide per gene correlate closely with those obtained using complementary DNA (cDNA) arrays. Most of the genes for which measurements differ are members of gene families that can only be distinguished by oligonucleotides. Because different oligonucleotide sequences can be specified for each array, we anticipate that ink-jet oligonucleotide array technology will be useful in a wide variety of DNA microarray applications.


Assuntos
Expressão Gênica , Hibridização In Situ/métodos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Oligonucleotídeos/química , Células Cultivadas , Cromatografia Líquida de Alta Pressão , DNA Complementar/metabolismo , Humanos , Processamento de Imagem Assistida por Computador , Células Jurkat , Células K562 , Oligonucleotídeos/síntese química , Fases de Leitura Aberta , Reação em Cadeia da Polimerase , RNA Complementar/metabolismo , RNA Mensageiro/metabolismo , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Saccharomyces cerevisiae , Sensibilidade e Especificidade , Fatores de Tempo , Transcrição Gênica , Tretinoína/química , Células Tumorais Cultivadas
9.
Nature ; 409(6822): 922-7, 2001 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-11237012

RESUMO

The most important product of the sequencing of a genome is a complete, accurate catalogue of genes and their products, primarily messenger RNA transcripts and their cognate proteins. Such a catalogue cannot be constructed by computational annotation alone; it requires experimental validation on a genome scale. Using 'exon' and 'tiling' arrays fabricated by ink-jet oligonucleotide synthesis, we devised an experimental approach to validate and refine computational gene predictions and define full-length transcripts on the basis of co-regulated expression of their exons. These methods can provide more accurate gene numbers and allow the detection of mRNA splice variants and identification of the tissue- and disease-specific conditions under which genes are expressed. We apply our technique to chromosome 22q under 69 experimental condition pairs, and to the entire human genome under two experimental conditions. We discuss implications for more comprehensive, consistent and reliable genome annotation, more efficient, full-length complementary DNA cloning strategies and application to complex diseases.


Assuntos
Cromossomos Humanos Par 22 , Biologia Computacional , Genoma Humano , Análise de Sequência com Séries de Oligonucleotídeos , Algoritmos , Processamento Alternativo , Linhagem Celular , DNA Complementar , Éxons , Projeto Genoma Humano , Humanos , Sondas de Oligonucleotídeos
10.
Equine Vet J ; 32(5): 379-84, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11037258

RESUMO

Exercise-induced pulmonary haemorrhage (EIPH) is characterised by blood in the airways after strenuous exercise and results from stress failure of the pulmonary capillaries. The purpose of this experiment was to establish a threshold value of transmural pulmonary arterial pressure at which haemorrhage occurs in the exercising horse. Five geldings, age 4-14 years, were run in random order once every 2 weeks at 1 of 4 speeds (9, 11, 13, 15 m/s); one day with no run was used as a control. Heart rate, pulmonary arterial pressure and oesophageal pressure were recorded for the duration of the run. Transmural pulmonary arterial pressure was estimated by electronic subtraction of the oesophageal pressure from the intravascular pulmonary arterial pressure. Within 1 h of the run, bronchoalveolar lavage was performed and the red and white blood cells in the fluid were quantified. Red cell counts in the lavage fluid from horses running at 9, 11 and 13 m/s were not significantly different from the control value, but after runs at 15 m/s, red cell counts were significantly (P<0.05) higher. White cell counts were not different from control values at any speed. Analysis of red cell count vs. transmural pulmonary arterial pressure indicated that haemorrhage occurs at approximately 95 mmHg. Red cell lysis in the lavage fluid was also apparent at transmural pulmonary arterial pressures above 90 mmHg. We conclude that, in the exercising horse, a pulmonary arterial pressure threshold exists above which haemorrhage occurs, and that pressure is often exceeded during high speed sprint exercise.


Assuntos
Hemorragia/veterinária , Doenças dos Cavalos/etiologia , Condicionamento Físico Animal/efeitos adversos , Circulação Pulmonar , Pressão Propulsora Pulmonar , Animais , Lavagem Broncoalveolar/veterinária , Contagem de Eritrócitos/veterinária , Hemorragia/etiologia , Hemorragia/fisiopatologia , Doenças dos Cavalos/fisiopatologia , Cavalos
11.
Proc Natl Acad Sci U S A ; 97(19): 10595-600, 2000 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-10984544

RESUMO

It is well established that signal transduction in sensory neurons of the rat olfactory epithelium involves a cAMP-signaling pathway. However, a small number of olfactory neurons specifically express cGMP-signaling components, namely a guanylyl cyclase (GC-D) and a cGMP-stimulated phosphodiesterase (PDE2). Here, we show that this subset of olfactory neurons expressing GC-D and PDE2 does also express the subunit of a cGMP-selective cyclic nucleotide-gated (CNG) channel that has been previously identified in cone photoreceptors. Further, components of the prototypical cAMP-signaling pathway could not be detected in this subpopulation of cells. These results imply that these neurons use an alternative signaling pathway, with cGMP as the intracellular messenger, and that, in these cells, the receptor current is initiated by the opening of cGMP-gated channels.


Assuntos
GMP Cíclico/metabolismo , Canais Iônicos/genética , Neurônios Receptores Olfatórios/metabolismo , Transdução de Sinais , Sequência de Aminoácidos , Animais , Linhagem Celular , Clonagem Molecular , Canais de Cátion Regulados por Nucleotídeos Cíclicos , DNA Complementar , Humanos , Imuno-Histoquímica , Dados de Sequência Molecular , Diester Fosfórico Hidrolases/metabolismo , Ratos , Ratos Sprague-Dawley
12.
Cell ; 102(1): 109-26, 2000 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-10929718

RESUMO

Ascertaining the impact of uncharacterized perturbations on the cell is a fundamental problem in biology. Here, we describe how a single assay can be used to monitor hundreds of different cellular functions simultaneously. We constructed a reference database or "compendium" of expression profiles corresponding to 300 diverse mutations and chemical treatments in S. cerevisiae, and we show that the cellular pathways affected can be determined by pattern matching, even among very subtle profiles. The utility of this approach is validated by examining profiles caused by deletions of uncharacterized genes: we identify and experimentally confirm that eight uncharacterized open reading frames encode proteins required for sterol metabolism, cell wall function, mitochondrial respiration, or protein synthesis. We also show that the compendium can be used to characterize pharmacological perturbations by identifying a novel target of the commonly used drug dyclonine.


Assuntos
Bases de Dados Factuais , Perfilação da Expressão Gênica , Saccharomyces cerevisiae/fisiologia , Parede Celular/fisiologia , Ergosterol/biossíntese , Proteínas Fúngicas/biossíntese , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Genes Fúngicos , Genes Reporter , Teste de Complementação Genética , Variação Genética , Humanos , Mitocôndrias/metabolismo , Modelos Genéticos , Mutagênese , Fases de Leitura Aberta , Fenótipo , Propiofenonas/farmacologia , Receptores sigma/genética , Ribossomos , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Esteroide Isomerases/genética , Transcrição Gênica
13.
Nat Genet ; 25(3): 333-7, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10888885

RESUMO

Expression profiling using DNA microarrays holds great promise for a variety of research applications, including the systematic characterization of genes discovered by sequencing projects. To demonstrate the general usefulness of this approach, we recently obtained expression profiles for nearly 300 Saccharomyces cerevisiae deletion mutants. Approximately 8% of the mutants profiled exhibited chromosome-wide expression biases, leading to spurious correlations among profiles. Competitive hybridization of genomic DNA from the mutant strains and their isogenic parental wild-type strains showed they were aneuploid for whole chromosomes or chromosomal segments. Expression profile data published by several other laboratories also suggest the use of aneuploid strains. In five separate cases, the extra chromosome harboured a close homologue of the deleted gene; in two cases, a clear growth advantage for cells acquiring the extra chromosome was demonstrated. Our results have implications for interpreting whole-genome expression data, particularly from cells known to suffer genomic instability, such as malignant or immortalized cells.


Assuntos
Aneuploidia , Cromossomos Fúngicos , Saccharomyces cerevisiae/genética , DNA Fúngico/análise , Expressão Gênica , Análise de Sequência com Séries de Oligonucleotídeos/métodos
14.
Neurology ; 54(11): 2066-71, 2000 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-10851364

RESUMO

OBJECTIVE: To test the hypothesis that nonsteroidal anti-inflammatory drugs (NSAIDs) and histamine H2 receptor antagonists (H2RAs) are associated with a decreased risk of AD in late life. BACKGROUND: Sustained use of non-aspirin NSAIDs has been repeatedly associated with a reduced occurrence of AD. Similar effects with aspirin have been weaker. One prior study showed a strong association between use of H2RAs and reduced AD prevalence. METHODS: In a population study of AD in Cache County, UT, we used a sequenced plan of sampling and case ascertainment to identify 201 cases of AD and 4425 participants with no indication of cognitive impairment. Independently, an interview and medicine chest inventory assessed use of several medicines including aspirin, non-aspirin NSAIDs, H2RAs, and three classes of "control" drugs not thought to be associated with AD. Follow-up questioning probed possible indications for use of these drugs. RESULTS: Compared with cognitively intact individuals, the AD cases had significantly less reported current use of NSAIDs, aspirin, and H2RAs. Stronger associations appeared when subjects reported use of both NSAIDs and aspirin (no H2RAs), two different NSAIDs (no H2RAs), or two different H2RAs (with neither aspirin nor NSAIDs). There was little or no such association with use of the control medicines. Adjustment for usage indication did not influence these findings, and there was no appreciable variation with number of APOE epsilon4 alleles. CONCLUSIONS: As predicted, use of NSAIDs and aspirin were specifically associated with reduced occurrence of AD. Notably, a previous observation of an inverse association of AD and use of H2RAs was also affirmed. Definitive evidence for a preventive action of these agents will require randomized prevention trials.


Assuntos
Doença de Alzheimer/prevenção & controle , Anti-Inflamatórios não Esteroides/uso terapêutico , Aspirina/uso terapêutico , Antagonistas dos Receptores H2 da Histamina/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Coleta de Dados , Humanos , Modelos Logísticos
15.
Science ; 287(5454): 873-80, 2000 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-10657304

RESUMO

Genome-wide transcript profiling was used to monitor signal transduction during yeast pheromone response. Genetic manipulations allowed analysis of changes in gene expression underlying pheromone signaling, cell cycle control, and polarized morphogenesis. A two-dimensional hierarchical clustered matrix, covering 383 of the most highly regulated genes, was constructed from 46 diverse experimental conditions. Diagnostic subsets of coexpressed genes reflected signaling activity, cross talk, and overlap of multiple mitogen-activated protein kinase (MAPK) pathways. Analysis of the profiles specified by two different MAPKs-Fus3p and Kss1p-revealed functional overlap of the filamentous growth and mating responses. Global transcript analysis reflects biological responses associated with the activation and perturbation of signal transduction pathways.


Assuntos
Proteínas de Ciclo Celular , Perfilação da Expressão Gênica , Regulação Fúngica da Expressão Gênica , Sistema de Sinalização das MAP Quinases , Proteínas Repressoras , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Proteínas Inibidoras de Quinase Dependente de Ciclina , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/fisiologia , Fase G1 , Genoma Fúngico , Lipoproteínas/farmacologia , Lipoproteínas/fisiologia , Fator de Acasalamento , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Família Multigênica , Análise de Sequência com Séries de Oligonucleotídeos , Peptídeos/farmacologia , Peptídeos/fisiologia , Feromônios , Proteína Quinase C/metabolismo , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/fisiologia , Fatores de Transcrição/metabolismo , Ativação Transcricional
16.
Development ; 126(23): 5353-64, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10556060

RESUMO

Rho GTPases play an important role in diverse biological processes such as actin cytoskeleton organization, gene transcription, cell cycle progression and adhesion. They are required during early Drosophila development for proper execution of morphogenetic movements of individual cells and groups of cells important for the formation of the embryonic body plan. We isolated loss-of-function mutations in the Drosophila Rho1 (Rho1) gene during a genetic screen for maternal-effect mutations, allowing us to investigate the specific roles Rho1 plays in the context of the developing organism. Here we report that Rho1 is required for many early events: loss of Rho1 function results in both maternal and embryonic phenotypes. Embryos homozygous for the Rho1 mutation exhibit a characteristic zygotic phenotype, which includes severe defects in head involution and imperfect dorsal closure. Two phenotypes are associated with reduction of maternal Rho1 activity: the actin cytoskeleton is disrupted in egg chambers, especially in the ring canals and embryos display patterning defects as a result of improper maintenance of segmentation gene expression. Despite showing imperfect dorsal closure, Rho1 does not activate downstream genes or interact genetically with members of the JNK signaling pathway, used by its relatives dRac and dCdc42 for proper dorsal closure. Consistent with its roles in regulating actin cytoskeletal organization, we find that Rho1 interacts genetically and physically with the Drosophila formin homologue, cappuccino. We also show that Rho1 interacts both genetically and physically with concertina, a G(alpha) protein involved in cell shape changes during gastrulation.


Assuntos
Proteínas de Drosophila , Drosophila/crescimento & desenvolvimento , Proteínas dos Microfilamentos , Mutação , Ovário/patologia , Fatores de Transcrição , Proteínas rho de Ligação ao GTP/genética , Actinas/ultraestrutura , Animais , Citoesqueleto/genética , Citoesqueleto/ultraestrutura , Drosophila/embriologia , Embrião não Mamífero , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Cabeça/anormalidades , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Homozigoto , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Morfogênese/fisiologia , Ovário/embriologia , Fenótipo , Fosfoproteínas Fosfatases/genética , Fosfoproteínas Fosfatases/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Transdução de Sinais , Proteína Wnt1 , Zigoto , Proteínas rho de Ligação ao GTP/metabolismo
17.
Neurology ; 53(2): 321-31, 1999 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-10430421

RESUMO

OBJECTIVE: To examine the prevalence of Alzheimer's disease (AD) and other dementias in relation to age, education, sex, and genotype at APOE. Recent studies suggest age heterogeneity in the risk of AD associated with the APOE genotype and a possible interaction between APOE-epsilon4 and female sex as risk factors. We studied these topics in the 5,677 elderly residents of Cache County, Utah, a population known for long life expectancy and high participation rates. METHODS: We screened for dementia with a brief cognitive test and structured telephone Dementia Questionnaire, then examined all individuals with apparent cognitive symptoms and a sample of others. We estimated age-specific prevalence of AD and other dementias and used multiple logistic regression models to describe relation of AD prevalence to age, sex, education, and APOE genotype. RESULTS: We found 335 demented individuals, 230 (69%) with definite, probable, or possible AD (positive predictive value versus autopsy confirmation 85%). The adjusted prevalence estimate for AD was 6.5% and for all dementias 9.6%. After age 90, the adjusted prevalence estimate for AD was 28% and for all dementias 38%. Regression models showed strong variation in AD prevalence with age, sex, education, and number of epsilon4 alleles (effect of epsilon2 not significant). Models were improved by a term for age-squared (negative coefficient) and by separate terms for interaction of age with presence of one or two epsilon4 alleles. An association of AD with female sex was ascribable entirely to individuals with epsilon4. CONCLUSIONS: In participants with no epsilon4 alleles, the age-specific prevalence of AD reached a maximum and then declined after age 95. In epsilon4 heterozygotes a similar maximum was noted earlier at age 87, in homozygotes at age 73. Female sex was a risk factor for AD only in those with epsilon4. The epsilon4 allele accounted for 70% of the population attributable risk for AD.


Assuntos
Doença de Alzheimer/epidemiologia , Apolipoproteínas E/análise , Distribuição por Idade , Idoso , Apolipoproteína E4 , Apolipoproteínas E/genética , Feminino , Genótipo , Humanos , Masculino , Programas de Rastreamento , Valor Preditivo dos Testes , Prevalência , Fatores de Risco , Distribuição por Sexo , Inquéritos e Questionários
18.
Nat Med ; 4(11): 1293-301, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9809554

RESUMO

We describe here a method for drug target validation and identification of secondary drug target effects based on genome-wide gene expression patterns. The method is demonstrated by several experiments, including treatment of yeast mutant strains defective in calcineurin, immunophilins or other genes with the immunosuppressants cyclosporin A or FK506. Presence or absence of the characteristic drug 'signature' pattern of altered gene expression in drug-treated cells with a mutation in the gene encoding a putative target established whether that target was required to generate the drug signature. Drug dependent effects were seen in 'targetless' cells, showing that FK506 affects additional pathways independent of calcineurin and the immunophilins. The described method permits the direct confirmation of drug targets and recognition of drug-dependent changes in gene expression that are modulated through pathways distinct from the drug's intended target. Such a method may prove useful in improving the efficiency of drug development programs.


Assuntos
Calcineurina/genética , Ciclosporina/farmacologia , Regulação Fúngica da Expressão Gênica , Imunofilinas/genética , Imunossupressores/farmacologia , Saccharomyces cerevisiae/genética , Tacrolimo/farmacologia , Desenho de Fármacos , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Genótipo , Modelos Biológicos , Mutação , Reação em Cadeia da Polimerase , Reprodutibilidade dos Testes , Saccharomyces cerevisiae/efeitos dos fármacos , Transdução de Sinais
20.
Endocrinology ; 139(2): 651-8, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9449637

RESUMO

The influence of CRF on testosterone production in primary mouse Leydig cell cultures was studied, and the type of CRF receptor (CRF-R) involved in this activity was determined. CRF directly stimulated testosterone production in mouse Leydig cells, but did not influence the maximum human (h)CG-induced testosterone production. The effect was time- and dose-dependent, saturable with an EC50 of 2.84 nM for hCRF, antagonized by the CRF antagonist alpha-helical CRF9-41, and accompanied by intracellular cAMP elevation. The rank order of potency of the natural CRF agonists, hCRF, ovine CRF, sauvagine, and urotensin, corresponded to that of their activities on CRF-R1 in rat pituitary cells and also to that reported for this receptor, but not for CRF-R2, when transfected into various cell lines. Furthermore, the difference in response of mouse Leydig cells to [11-D-Thr,12-D-Phe]- and [13-D-His,14-D-Leu]-ovine CRF corresponded to that measured when COS cells expressing CRF-R1 were activated, but was considerably smaller than that observed for activation of COS cells expressing CRF-R2alpha or -R2beta. The messenger RNA encoding the mouse CRF-R1 was detected by RT-PCR in mouse Leydig cell preparations. In contrast to mouse Leydig cells, CRF agonists had no influence on the basal testosterone and cAMP production by rat Leydig cells, nor did the agonists or antagonist change the hCG-stimulated testosterone and cAMP production by these cells. It is concluded that mouse Leydig cells express CRF-R1, mediating elevation of testosterone production by CRF agonists through cAMP. Because potencies of CRF agonists in activating mouse Leydig cells were more than 10-fold lower compared with their potencies in stimulating rat pituitary cells, it is suggested that the coupling of the CRF-R1 to intracellular signaling in Leydig cells is different from that in corticotropic pituitary cells, at least in quantitative terms.


Assuntos
Hormônio Liberador da Corticotropina/agonistas , Células Intersticiais do Testículo/metabolismo , Receptores de Hormônio Liberador da Corticotropina/fisiologia , Testosterona/biossíntese , Hormônio Adrenocorticotrópico/metabolismo , Animais , Células COS , Hormônio Liberador da Corticotropina/análogos & derivados , Hormônio Liberador da Corticotropina/química , AMP Cíclico/metabolismo , Humanos , Isomerismo , Masculino , Camundongos , Fragmentos de Peptídeos/farmacologia , Adeno-Hipófise/citologia , Adeno-Hipófise/metabolismo , Ratos , Ratos Endogâmicos , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Ovinos , Estimulação Química
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