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1.
Am J Physiol Endocrinol Metab ; 281(4): E757-65, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11551852

RESUMO

In a longitudinal study of the effects of moderate (70%) dietary restriction (DR) on aging, plasma glucose and insulin concentrations were measured from semiannual, frequently sampled intravenous glucose tolerance tests (FSIGTT) in 30 adult male rhesus monkeys. FSIGTT data were analyzed with Bergman's minimal model, and analysis of covariance revealed that restricted (R) monkeys exhibited increased insulin sensitivity (S(I), P < 0.001) and plasma glucose disappearance rate (K(G), P = 0.015), and reduced fasting plasma insulin (I(b), P < 0.001) and insulin response to glucose (AIR(G), P = 0.023) compared with control (C; ad libitum-fed) monkeys. DR reduced the baseline fasting hyperinsulinemia of two R monkeys, whereas four C monkeys have maintained from baseline, or subsequently developed, fasting hyperinsulinemia; one has progressed to diabetes. Compared with only the normoinsulinemic C monkeys, R monkeys exhibited similarly improved FSIGTT and minimal-model parameters. Thus chronic DR not only has protected against the development of insulin resistance in aging rhesus monkeys, but has also improved glucoregulatory parameters compared with those of otherwise normoinsulinemic monkeys.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 2/fisiopatologia , Dieta Redutora , Ingestão de Energia , Hiperinsulinismo/fisiopatologia , Resistência à Insulina/fisiologia , Insulina/sangue , Macaca mulatta/crescimento & desenvolvimento , Envelhecimento , Análise de Variância , Animais , Índice de Massa Corporal , Peso Corporal , Progressão da Doença , Jejum , Teste de Tolerância a Glucose , Homeostase , Insulina/metabolismo , Secreção de Insulina , Masculino , Modelos Biológicos , Fatores de Tempo
2.
J Gen Intern Med ; 15(9): 611-9, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11029674

RESUMO

OBJECTIVE: To describe functional deficits among older adults living alone and receiving home nursing following medical hospitalization, and the association of living alone with lack of functional improvement and nursing home utilization 1 month after hospitalization. DESIGN: Secondary analysis of a prospective cohort study. PARTICIPANTS: Consecutive sample of patients age 65 and over receiving home nursing following medical hospitalization. Patients were excluded for new diagnosis of myocardial infarction or stroke in the previous 2 months, diagnosis of dementia if living alone, or nonambulatory status. Of 613 patients invited to participate, 312 agreed. MEASUREMENTS: One week after hospitalization, patients were assessed in the home for demographic information, medications, cognition, and self-report of prehospital and current mobility and function in activities of daily living (ADLs) and independent activities of daily living (IADLs). One month later, patients were asked about current function and nursing home utilization. The outcomes were lack of improvement in ADL function and nursing home utilization 1 month after hospitalization. RESULTS: One hundred forty-one (45%) patients lived alone. After hospital discharge, 40% of those living alone and 62% of those living with others had at least 1 ADL dependency (P =.0001). Patients who were ADL-dependent and lived alone were 3.3 (95% confidence interval [95% CI], 1.4 to 7. 6) times less likely to improve in ADLs and 3.5 (95% CI, 1.0 to 11. 9) times more likely to be admitted to a nursing home in the month after hospitalization. CONCLUSION: Patients who live alone and receive home nursing after hospitalization are less likely to improve in function and more likely to be admitted to a nursing home, compared with those who live with others. More intensive resources may be required to continue community living and maximize independence.


Assuntos
Atividades Cotidianas , Serviços de Assistência Domiciliar , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Demografia , Feminino , Humanos , Masculino , Alta do Paciente , Estudos Prospectivos , Características de Residência , Fatores de Risco , Apoio Social , Fatores Socioeconômicos
3.
Sleep ; 23(4): 535-41, 2000 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-10875560

RESUMO

OBJECTIVE: To investigate the effects of sleep apnea (SA) on the quality of life (QOL). DESIGN: A prospective study of QOL in patients with and without SA as defined by an apnea-hypopnea index (AHI) >5. SETTING: University-based outpatient clinics. PATIENTS: Primary care patients followed in a general internal medicine clinic as well as those referred to a sleep disorders clinic at the University of Wisconsin Hospital and Clinics were consecutively recruited and classified into 3 groups of subjects: (1) patients without SA (AHI<5) (n=46), (2) patients with mild SA (AHI 5-15) (n=16), and (3) patients with moderate to severe SA (AHI>15) (n=21). INTERVENTIONS: NA. MEASUREMENTS: QOL was assessed with the Medical Outcomes Study SF-36 Health Survey. Health history and demographic data were obtained via structured interview and medical record review. All subjects underwent overnight polysomnography for diagnosis of SA. RESULTS: After controlling for age, gender, body mass index, and number of comorbid conditions, the association between sleep apnea and QOL was significant in the domains of physical functioning and role limitation due to physical health problems (p<0.05) and was borderline in vitality (p<0.1). Patients with both mild and moderately severe SA scored significantly lower (worse) than did patients without SA in physical functioning and in role limitations due to physical-health (82 and 83 vs. 92, respectively). Moderate to severe SA subjects scored significantly lower in vitality than did subjects without SA (51 vs. 64, p<0.05). Subscales analysis revealed that subjects with moderate to severe SA had significantly lower scores that did those without SA in positive affect (69 vs. 79), current health perceptions (71 vs. 80) and vitality (50 vs. 70), p<0.05 for all comparisons. A large percentage of patients without SA had perfect scores of 100 (ceiling effect) on the physical, social, and role functioning scales. CONCLUSIONS: SA has an independent impact on several QOL domains after adjusting for differences in age, gender, body mass index, and comorbidity. QOL outcomes were likely attenuated by ceiling effects. Disentangling the scales that measure multidimensional QOL (positive and negative aspects) enhanced the ability of the SF-36 to detect important consequences of sleep apnea on QOL.


Assuntos
Qualidade de Vida , Síndromes da Apneia do Sono/diagnóstico , Depressão/complicações , Depressão/diagnóstico , Depressão/epidemiologia , Distúrbios do Sono por Sonolência Excessiva/etiologia , Feminino , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Polissonografia/métodos , Prevalência , Estudos Prospectivos , Índice de Gravidade de Doença , Síndromes da Apneia do Sono/complicações
4.
J Gerontol A Biol Sci Med Sci ; 54(7): B283-90, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10462160

RESUMO

Dietary restriction (DR) is the only intervention that has been shown to increase average and median life span in laboratory rodents. The effect of long-term, moderate DR on body composition and fat distribution was evaluated in male rhesus monkeys. Thirty animals (8-14 years of age)fed either 30% less than baseline intake (R, n = 15) or allowed to eat to satiety (C, n = 15), have been assessed semiannually using somatometrics and dual-energy alpha-ray absorptiometry (DXA)for 7.5 years. R subjects have reduced body weight (p <.0001), total body fat (p < .0001), and percentage body fat located in the abdominal region (p < .05). In addition, there has been a sustained reduction in plasma leptin concentrations (p <.001). These findings suggest reduced risk for common morbidities, such as insulin resistance, dyslipidemia, and type 2 diabetes mellitus, that are associated with advancing age and increased levels of bodyfat, especially in the visceral depot.


Assuntos
Tecido Adiposo/anatomia & histologia , Composição Corporal , Dieta , Absorciometria de Fóton , Animais , Peso Corporal , Leptina , Macaca mulatta , Masculino , Obesidade/complicações , Proteínas/análise
6.
Age Ageing ; 28(2): 211-6, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10350421

RESUMO

OBJECTIVES: L-carnitine and dehydro-epiandrosterone (DHEA) independently promote mitochondrial energy metabolism. We therefore wondered if an age-related deficiency of L-carnitine or DHEA may account for the declining energy metabolism associated with age. METHODS: we evaluated serum levels of L-carnitine and the sulphated derivative of DHEA (DHEAS) in cross-sectional study of 216 healthy adults, aged 20-95. RESULTS: serum DHEAS levels declined, while total carnitine levels increased with age (P < 0.0001). Total and free carnitine and DHEAS levels were lower in women than men (P < 0.0001). Esterified/free (E/F) carnitine (inversely related to carnitine availability) increased with age in both sexes (P=0.012). CONCLUSION: reduced carnitine availability correlates with the age-related decline of DHEAS levels. These results are consistent with the hypothesis that decreased energy metabolism with age relates to DHEAS levels and carnitine availability.


Assuntos
Envelhecimento/sangue , Carnitina/sangue , Sulfato de Desidroepiandrosterona/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais
7.
Mol Reprod Dev ; 53(1): 27-41, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10230814

RESUMO

Cytogenetic and molecular deletion analyses of azoospermic and oligozoospermic males have suggested the existence of AZoospermia Factor(s) (AZF) residing in deletion intervals 5 and 6 of the human Y-chromosome and coinciding with three functional regions associated with spermatogenic failure. Nonpolymorphic microdeletions in AZF are associated with a broad spectrum of testicular phenotypes. Unfortunately, Sequence Tagged Sites (STSs) employed in screening protocols range broadly in number and mapsite and may be polymorphic. To thoroughly analyze the AZF region(s) and any correlations that may be drawn between genotype and phenotype, we describe the design of nine multiplex PCR reactions derived from analysis of 136 loci. Each multiplex contains 4-8 STS primer pairs, amplifying a total of 48 Y-linked STSs. Each multiplex consists of one positive control: either SMCX or MIC2. We screened four populations of males with these STSs. Population I consisted of 278 patients diagnosed as having significant male factor infertility: either azoospermia, severe oligozoospermia associated with hypogonadism and spermatogenic arrest or normal sperm counts associated with abnormal sperm morphology. Population II consisted of 200 unselected infertile patients. Population III consisted of 36 patients who had previously been shown to have aneuploidy, cytological deletions or translocations involving the Y-chromosome or normal karyotypes associated with severe phenotype abnormalities. Population IV consisted of 920 fertile (control) males. The deletion rates in populations I, II and III were 20.5%, 7% and 58.3%, respectively. A total of 92 patients with deletions were detected. The deletion rate in population IV was 0.87% involving 8 fertile individuals and 4 STSs which were avoided in multiplex panel construction. The ability of the nine multiplexes to detect pathology associated microdeletions is equal to or greater than screening protocols used in other studies. Furthermore, the data suggest a fourth AZF region between AZFb and AZFc, which we have termed AZFd. Patients with microdeletions restricted to AZFd may present with mild oligozoospermia or even normal sperm counts associated with abnormal sperm morphology. Though a definitive genotype/phenotype correlation does not exist, large deletions spanning multiple AZF regions or microdeletions restricted to AZFa usually result in patients with Sertoli Cell Only (SCO) or severe oligozoospermia, whereas microdeletions restricted to AZFb or AZFc can result in patients with phenotypes which range from SCO to moderate oligozoospermia. The panel of nine multiplexed reactions, the Y-deletion Detection System (YDDS), provides a fast, efficient and accurate method of assessing the integrity of the Y-chromosome. To date, this study provides the most extensive screening of a proven fertile male population in tandem with 514 infertile males, derived from three different patient selection protocols.


Assuntos
Oligospermia/genética , Deleção de Sequência , Cromossomo Y , Feminino , Humanos , Infertilidade Masculina/genética , Masculino , Fenótipo , Sitios de Sequências Rotuladas
8.
Breast Cancer Res Treat ; 58(3): 281-6, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10718489

RESUMO

There are very few data about the efficacy and toxicity of adjuvant systemic therapies for breast cancer in non-western populations. In 1993 in Vietnam we began a randomized controlled clinical trial on premenopausal women with operable breast cancer comparing adjuvant surgical oophorectomy plus tamoxifen with observation and this same combined hormonal treatment on recurrence. We evaluated the symptoms reported at regular follow-up visits by the first 482 premenopausal women entered in this clinical trial and treated with surgical oophorectomy plus tamoxifen or observation. Hot flash frequency and intensity, vaginal discharge, and genital pruritus were the only symptoms to occur more frequently in oophorectomy and tamoxifen-treated subjects. Seventy-seven percent of oophorectomy/tamoxifen subjects reported grade 1 or more and 44% grade 2 or more hot flash frequency symptoms in the first 12 months, versus 9% and 1% of observation subjects, respectively. Twenty percent of oophorectomy/tamoxifen subjects had grade 2 or greater intensity of hot flashes some time in the first 12 months versus 0% in observation subjects. Through three years, vasomotor symptoms were reported more frequently in oophorectomy/tamoxifen-treated women (in 23% vs. 3% at three years, mostly grade 1 toxicities). While noted and persistent vasomotor symptoms were found with oophorectomy plus tamoxifen in this population of Vietnamese women, these were of lower grades and tolerable. This adjuvant treatment may be widely accepted if it is demonstrated to be effective in this population.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/terapia , Ovariectomia , Tamoxifeno/uso terapêutico , Adulto , Antineoplásicos Hormonais/efeitos adversos , Neoplasias da Mama/patologia , Terapia Combinada , Feminino , Seguimentos , Fogachos , Humanos , Ovariectomia/efeitos adversos , Pré-Menopausa , Tamoxifeno/efeitos adversos , Resultado do Tratamento , Vagina/patologia
9.
Pediatrics ; 102(1 Pt 1): 77-83, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9651417

RESUMO

OBJECTIVE: Asthma is a significant cause of morbidity and mortality in children. The objective of this study was to determine whether the federal program Head Start in Dane County, Wisconsin, could be used as a mechanism to identify preschool-aged children with asthma. DESIGN: Five-year, cross-sectional survey of parents with children enrolled in Head Start. METHODS: Investigator-administered asthma screening questionnaire to parents of enrolling Head Start children in Dane County, Wisconsin. MEASUREMENTS: Asthma prevalence and asthma-related health care use, including emergency department visits, hospitalizations, and medication usage, were measured using an asthma screening questionnaire developed by investigators. RESULTS: Information was gathered on 2215 children. The prevalence of physician-diagnosed asthma in the screened children was 15.8%. Parental reports of physician-diagnosed asthma were validated in a subset of 133 children, with a 98.5% confirmation rate. Independent risk factors for asthma included male gender (relative risk, 1.4) and African-American ethnicity (relative risk, 1.4). Asthma-related morbidity was substantial with 26.7% of identified children hospitalized for asthma and 54.5% with an emergency department visit during their lifetime. The majority of children (46.4%) were treated with intermittent, quick relief medications (beta-agonists) alone, whereas only 6.1% were on daily, long-term controller medications. CONCLUSIONS: Asthma screening through a Head Start program provides an effective means of targeting preschool-aged children from socioeconomic groups at high risk for asthma. Identification of children early in the disease course and those at high risk for asthma provides an ideal opportunity for the implementation of preventive and therapeutic interventions.


Assuntos
Asma/epidemiologia , Intervenção Educacional Precoce/estatística & dados numéricos , Programas de Rastreamento/estatística & dados numéricos , População Rural/estatística & dados numéricos , Asma/diagnóstico , Serviços de Saúde da Criança/estatística & dados numéricos , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Incidência , Masculino , Fatores de Risco , Fatores Socioeconômicos , Wisconsin/epidemiologia
10.
J Virol ; 71(12): 9672-8, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9371632

RESUMO

Lymphocytic choriomeningitis virus (LCMV) infection of normal mice results in a fatal immunopathologic meningitis mediated by CD8+ cytotoxic T lymphocytes (CTL). We have previously shown that female beta2-microglobulin-deficient (beta2m-/-) mice, which are also deficient in CD8+ T cells, are susceptible to LCMV-induced immune-mediated meningitis, characterized by significant weight loss and mortality. This LCMV disease in beta2m-/- mice is mediated by CD4+ T lymphocytes. Our previous studies have also demonstrated that male beta2m-/- mice are less susceptible than female beta2m-/- mice to LCMV-induced, immune-mediated mortality and weight loss. In this report, we show that vaccination of male beta2m-/- mice enhances immunopathology following intracranial infection with LCMV. We observed increased production of gamma interferon (IFN-gamma), an increase in CD4+ CTL precursor frequency, and an increased frequency of IFN-gamma-producing cells from spleen cells of vaccinated male beta2m-/- mice. Vaccinated male beta2m-/- mice also had significantly increased inflammation in the cerebrospinal fluid (CSF), characterized by a large CD4+ T-cell infiltrate. CSF cells from vaccinated mice showed increased production of IFN-gamma on day 7 postchallenge. Neither vaccinated nor control beta2m-/- mice were able to clear virus, and the two groups had similarly high levels of virus early after infection. These results suggest that the magnitude of the early immune response is more important than the level of virus in the brain in determining the outcome of immunopathology in beta2m-/- mice. We show here that vaccination can increase CD4+ T-cell-dependent immunopathology to a persistent viral infection.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Coriomeningite Linfocítica/imunologia , Microglobulina beta-2/imunologia , Animais , Encéfalo/virologia , Linhagem Celular , Cricetinae , Modelos Animais de Doenças , Deleção de Genes , Glicoproteínas/imunologia , Interferon gama/biossíntese , Interferon gama/líquido cefalorraquidiano , Coriomeningite Linfocítica/prevenção & controle , Coriomeningite Linfocítica/virologia , Masculino , Camundongos , Baço/virologia , Vacinação , Vaccinia virus/imunologia , Proteínas Virais/imunologia , Latência Viral , Redução de Peso , Microglobulina beta-2/genética
11.
Am J Clin Pathol ; 108(4): 406-10, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9322593

RESUMO

We evaluated 500 consecutive patient serum samples for the presence of six autoantibodies by three antibody detection methods: immunodiffusion, immunoblot, and enzyme immunoassay. Clinical data were reviewed for each patient with positive antibody test results. Serum samples from 60 patients revealed antibodies to Sm, ribonucleoprotein (RNP), SSA/Ro, SSB/La, Scl-70, or Jo-1. There were 7 false-positive test results (1%). All three methods detected autoantibodies in 36 (68%) of 53 patients with connective tissue disease. Immunoblot was the most sensitive method to detect autoantibodies (92%). Enzyme immunoassay and immunodiffusion were less sensitive (81% and 74%, respectively). Antiribonucleoprotein and anti-SSB/La antibodies were more often detected by immunoblotting, whereas anti-SSA/Ro antibodies were more often detected by enzyme immunoassay. Newer antibody detection methods (immunoblot and enzyme immunoassay) are less time consuming than immunodiffusion and show good interassay sensitivity without loss of specificity. A combination of immunoblot and enzyme immunoassay yielded excellent assay sensitivity (100%) and specificity (99%) for detection of autoantibodies.


Assuntos
Autoanticorpos/sangue , Autoantígenos/imunologia , Doenças do Tecido Conjuntivo/imunologia , Imunodifusão , RNA Citoplasmático Pequeno , Ribonucleoproteínas/imunologia , Humanos , Imunodifusão/métodos , Sensibilidade e Especificidade , Proteínas Centrais de snRNP , Antígeno SS-B
12.
J Am Coll Cardiol ; 30(3): 791-8, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9283542

RESUMO

OBJECTIVES: We sought to assess the odds of experiencing adverse effects with low dose amiodarone therapy compared with placebo. BACKGROUND: An estimate of the likelihood of experiencing amiodarone-related adverse effects with exposure to low daily doses of the drug is lacking in the published reports, and little information is available on adverse effect event rates in control groups not receiving the drug. METHODS: Data from four published trials involving 1,465 patients were included in a meta-analysis design. The criteria for inclusion were 1) double-blind, placebo-controlled design; 2) absence of a crossover design between patient groups; 3) mean follow-up of at least 12 months; 4) maintenance amiodarone dose < or = 400 mg/day; and 5) presence of an explicit description of adverse effects. Data were pooled after testing for homogeneity of treatment effects across trials, and summary odds ratios were calculated by the Peto-modified Mantel-Haenszel method for each adverse effect. RESULTS: The mean amiodarone dose per day ranged from 152 to 330 mg; 738 patients were randomized to receive amiodarone and 727 placebo. Exposure to amiodarone in this dose range, for a minimal duration of 12 months, resulted in odds similar to those of placebo for hepatic and gastrointestinal adverse effects, but in significantly higher odds than those of placebo (p < 0.05) for experiencing thyroid (odds ratio [OR] 4.2, 95% confidence interval [CI] 2.0 to 8.7), neurologic (OR 2.0, 95% CI 1.1 to 3.7), skin (OR 2.5, 95% CI 1.1 to 6.2), ocular (OR 3.4, 95% CI 1.2 to 9.6) and bradycardic (OR 2.2, 95% CI 1.1 to 4.3) adverse effects. A trend toward increased odds of pulmonary toxicity was noted (OR 2.0, 95% CI 0.9 to 5.3), but this did not reach statistical significance (p = 0.07). The unadjusted total incidence of drug discontinuation was 22.9% in the amiodarone group and 15.4% in the placebo group. The odds of discontinuing the drug in the amiodarone group was approximately 1.5 times that of the placebo group (OR 1.52, 95% CI 1.2 to 1.9) (p = 0.003). CONCLUSIONS: Compared with placebo, there is a higher likelihood of experiencing several amiodarone-related adverse effects with exposure to low daily doses of the drug. Thus, although low dose amiodarone may be well tolerated, it is not free of adverse effects.


Assuntos
Amiodarona/efeitos adversos , Antiarrítmicos/efeitos adversos , Amiodarona/administração & dosagem , Antiarrítmicos/administração & dosagem , Humanos , Razão de Chances , Ensaios Clínicos Controlados Aleatórios como Assunto
13.
J Gen Intern Med ; 12(5): 274-83, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9159696

RESUMO

OBJECTIVE: To assess the effectiveness of brief interventions in heavy drinkers by analyzing the outcome data and methodologic quality. DESIGN: (1) Qualitative analysis of randomized control trials (RCTs) using criteria from Chalmers' scoring system; (2) calculating and combining odds ratios (ORs) of RCTs using the One-Step (Peto) and the Mantel-Haenszel methods. STUDY SELECTION AND ANALYSIS: A MEDLINE and PsycLIT search identified RCTs testing brief interventions in heavy alcohol drinkers. Brief interventions were less than 1 hour and incorporated simple motivational counseling techniques much like outpatient smoking cessation programs. By a single-reviewer, nonblinded format, eligible studies were selected for adult subjects, sample sizes greater than 30, a randomized control design, and incorporation of brief alcohol interventions. Methodologic quality was assessed using an established scoring system developed by Chalmers and colleagues. Outcome data were combined by the One-Step (Peto) method; confidence limits and chi 2 test for heterogeneity were calculated. RESULTS: Twelve RCTs met all inclusion criteria, with an average quality score of 0.49 + or - 0.17. This was comparable to published average scores in other areas of research (0.42 + or - 0.16). Outcome data from RCTs were pooled, and a combined OR was close to 2 (1.91; 95% confidence interval 1.61-2.27) in favor of brief alcohol interventions over no intervention. This was consistent across gender, intensity of intervention, type of clinical setting, and higher-quality clinical trials. CONCLUSIONS: Heavy drinkers who received a brief intervention were twice as likely to moderate their drinking 6 to 12 months after an intervention when compared with heavy drinkers who received no intervention. Brief intervention is a low-cost, effective preventive measure for heavy drinkers in outpatient settings.


Assuntos
Alcoolismo/reabilitação , Adulto , Alcoolismo/terapia , Estudos de Avaliação como Assunto , Feminino , Humanos , Masculino , Razão de Chances , Prognóstico , Ensaios Clínicos Controlados Aleatórios como Assunto , Estatística como Assunto , Fatores de Tempo , Resultado do Tratamento
14.
J Nutr ; 127(12): 2293-301, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9405577

RESUMO

We previously reported that energy restriction (ER) of mice attenuated age-associated increases in serum levels of interleukin-6 (IL-6). Here, we studied peripheral blood mononuclear cells (PBMC) from male rhesus monkeys to investigate the following: 1) the production of IL-6 and other cytokines become dysregulated with aging; 2) ER influences cytokine production and mRNA expression; and, 3) oxidative stress, as induced in vitro by xanthine and xanthine oxidase (X/XOD), influences cytokine mRNA and protein levels. Two types of comparisons were made as follows: 1) between normally fed young (6-9 y) and old monkeys (22-33 y); and 2) between middle-aged monkeys (15-21 y) fed either a normal energy intake or subjected to ER (for 5.5 y at 30% less than base-line intake). IL-6 protein levels and X/XOD-induced IL-6 mRNA levels in PBMC from old monkeys were significantly greater than those in PBMC from young animals. In contrast, interleukin-1beta (IL-1beta) and interleukin-8 mRNA levels were not strongly influenced by advancing age. X/XOD, which increased levels of protein carbonyls (indicative of oxidative damage) in PBMC, induced the expression of all three cytokines. ER reduced IL-6 protein and mRNA levels induced by X/XOD and the unstimulated mRNA levels of IL-1beta. These results indicate that, in a nonhuman primate model, oxidative stress may contribute to age-associated increases in the levels of certain cytokines and that adult-onset ER partially ameliorates this alteration.


Assuntos
Envelhecimento/metabolismo , Ingestão de Energia , Interleucina-6/biossíntese , Leucócitos Mononucleares/metabolismo , Estresse Oxidativo , Animais , Interleucinas/biossíntese , Leucócitos Mononucleares/efeitos dos fármacos , Macaca mulatta , Masculino , Xantina/farmacologia , Xantina Oxidase/farmacologia
15.
Bone ; 19(5): 485-92, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8922647

RESUMO

Dual-energy X-ray absorptiometry (DXA) can be used to assess bone mass in nonhuman primates; however, the changes in bone mineral across the lifespan have not been well described. The purpose of this cross-sectional study was to evaluate the effect of maturation and subsequent aging on bone mineral content (BMC) and bone size (two dimensional bone area) in female rhesus monkeys at sites analogous to those commonly evaluated in humans. Total body (n = 178) and lumbar spine (n = 167) DXA scans were performed on female rhesus monkeys aged 2.8 to 34.6 years. Radius scans (n = 86) were performed on monkeys aged 9.7 to 34.6 years. Measurement precision was comparable to that reported for humans. At all sites, BMC was highly correlated with bone area (p = 0.0001), which was positively correlated with both body weight (p < or = 0.002) and age (p < or = 0.08). Total body and lumbar spine BMC and bone area increased with maturation (p < 0.0001) until age 11 and then remained stable with further advancing age. There was little change in total body and lumbar spine area-adjusted BMC across the lifespan. At the radial sites, there were no significant changes in BMC or bone area with age, but the area-adjusted BMC and the weight- and area-adjusted BMC declined in older animals (p < 0.05). In conclusion, the female rhesus monkey does not attain peak bone mass until age 11. Significant bone loss at later ages was observed only at radial sites.


Assuntos
Envelhecimento/patologia , Densidade Óssea/fisiologia , Osteoporose Pós-Menopausa/fisiopatologia , Absorciometria de Fóton , Animais , Peso Corporal/fisiologia , Estudos Transversais , Modelos Animais de Doenças , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/fisiologia , Macaca mulatta , Rádio (Anatomia)/diagnóstico por imagem , Rádio (Anatomia)/fisiologia , Análise de Regressão
16.
J Am Geriatr Soc ; 43(3): 236-9, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7884109

RESUMO

OBJECTIVE: To determine if plasma levels of Interleukin-6 (IL-6) across the lifespan correlate with bone density or plasma osteocalcin. DESIGN: Cross-sectional study. PARTICIPANTS: Forty-five healthy community-dwelling volunteers aged 25-74 years. Exclusion criteria were smoking use of medications known to affect bone metabolism (corticosteroids, heparin, thyroxine, thiazides, and anticonvulsants), and presence of chronic inflammatory disease. MEASUREMENTS: Bone density was measured by dual-energy X-ray absorptiometry at the femoral neck and lumbar spine. Plasma levels of IL-6 and osteocalcin were determined by ELISA and RIA, respectively. RESULTS: Plasma levels of IL-6 increased with advancing age (P < .0001) and correlated with postmenopausal status (P < .0001). No correlation was observed between plasma IL-6 level and bone mineral density at either the lumbar spine or femoral neck, and none was observed with plasma osteocalcin. CONCLUSIONS: The elevation of plasma IL-6 observed following menopause is consistent with the proposed importance of estrogen in the regulation of IL-6. These findings do not provide support for a role of IL-6 in determination of peak bone density or subsequent development of osteoporosis. However, it is possible that plasma levels of IL-6 differ from those in the bone microenvironment.


Assuntos
Densidade Óssea , Interleucina-6/sangue , Osteoporose Pós-Menopausa/sangue , Pós-Menopausa/sangue , Absorciometria de Fóton , Adulto , Fatores Etários , Idoso , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Osteocalcina/sangue , Osteoporose Pós-Menopausa/diagnóstico por imagem
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