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1.
Mult Scler ; 10(6): 690-704, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15584496

RESUMO

Although there is increasing interest in measuring the quality of life (QoL) of people with multiple sclerosis (MS), relatively little is known about the issues of importance to people severely affected by MS. In the first of two systematic reviews, we searched the literature to identify measures that have been used to assess health-related QoL in people with MS, and described their measurement properties in terms of validity, reliability, responsiveness to change, and appropriateness for QoL assessment in people severely affected by MS. In the second review, we identified care domains important to people with MS, by reviewing survey, focus group and interview studies involving people with MS and/or their caregivers. Forty-six studies evaluating 12 disease-specific and ten generic QoL measures for patients, and one disease-specific measure for caregivers, satisfied all inclusion criteria. Sixteen focus group or interview studies and 51 questionnaire-based studies evaluated domains of care important to people with MS, and seven qualitative and 11 questionnaire-based studies assessed domains of care important to their caregivers. From these studies, we identified 15 domains of care important to people with MS and 12 domains important to caregivers. QoL measures differed markedly in their coverage of these care domains. Moreover, each measure fulfilled some but not all criteria of validity, reliability, responsiveness, and appropriateness. Further work is needed to clarify the domains of care relevant to people with severe MS, and to measure health-related QoL in this population.


Assuntos
Esclerose Múltipla/psicologia , Avaliação de Resultados em Cuidados de Saúde , Cuidados Paliativos , Qualidade de Vida , Índice de Gravidade de Doença , Humanos , Auditoria Médica , Esclerose Múltipla/terapia
2.
J Subst Abuse Treat ; 20(1): 89-91, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11239733

RESUMO

This article describes an intervention for college students cited for alcohol-related infractions of the student code of conduct. First-time offenders are required to attend a three-hour class that includes educational, attitudinal and skills-based activities. Students also complete self-report measures of quantity/frequency of consumption and are mailed personalized drinking feedback one week following the group session. A preliminary evaluation of the program is described and the intervention is discussed in relation to other programs available on campus.


Assuntos
Alcoolismo/prevenção & controle , Psicoterapia Breve/métodos , Estudantes/psicologia , Adolescente , Adulto , Humanos , Estudantes/estatística & dados numéricos , Resultado do Tratamento
3.
Exp Gerontol ; 35(9-10): 1251-65, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11113606

RESUMO

Aging in men is associated with a decline in trophic factors such as testosterone (T), alterations in body composition and impaired energy and body weight regulation. We performed studies to investigate the mechanisms underlying age-related changes in the neuroendocrine control of testis function, body composition, food intake and body weight in the Brown Norway (BN) rat. We found that similar to aging men, male BN rats demonstrate both primary and secondary testicular failure with aging without confounding age-related tumors, hormonal changes and systemic illnesses. With aging, these animals have blunted circadian variations in luteinizing hormone (LH) and T, and decreased hypothalamic gonadotropin-releasing hormone (GnRH) synthetic capacity with preserved pituitary gonadotropin responses to GnRH. We found that aging male BN rats have increased peripheral and visceral adiposity associated with increased insulin and leptin levels, and decreased relative lean body mass and muscle mass. We found that these rats exhibit reduced food intake and body weight gain associated with decreased hypothalamic neuropeptide Y (NPY) gene expression in the arcuate nucleus (ARC), both during ad-libitum feeding and after a 72-h fast. Recently, we found that old male BN rats treated chronically with troglitazone, an insulin sensitizer, lowered high insulin and leptin levels, decreased body fat, and corrected the blunted food intake and body weight gain response to fasting without affecting basal ARC NPY gene expression. These findings suggested that hyperinsulinemia and/or hyperleptinemia associated with aging may contribute to the age-related impairment in energy and weight regulation. Our studies suggest that the aging male BN rat is an excellent model to investigate the mechanisms underlying the age-associated changes in the neuroendocrine control of body composition, energy intake and body weight.


Assuntos
Envelhecimento/fisiologia , Peso Corporal/fisiologia , Sistemas Neurossecretores/fisiologia , Reprodução/fisiologia , Tiazolidinedionas , Animais , Núcleo Arqueado do Hipotálamo/metabolismo , Composição Corporal/fisiologia , Cromanos/farmacologia , Ingestão de Alimentos/efeitos dos fármacos , Ingestão de Alimentos/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Hormônio Liberador de Gonadotropina/genética , Hormônio Liberador de Gonadotropina/farmacologia , Gonadotropinas Hipofisárias/metabolismo , Humanos , Hipoglicemiantes/farmacologia , Insulina/sangue , Leptina/sangue , Masculino , Modelos Animais , Neuropeptídeo Y/genética , Hipófise/efeitos dos fármacos , Hipófise/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Endogâmicos BN , Testículo/fisiopatologia , Tiazóis/farmacologia , Troglitazona , Aumento de Peso/efeitos dos fármacos , Aumento de Peso/fisiologia
4.
J Androl ; 21(1): 72-84, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10670522

RESUMO

As is the case in humans, aging male Brown Norway (BN) rats exhibit both primary and secondary (hypothalamic/pituitary) testicular failure. We hypothesized that secondary testicular failure in aging BN rats is due to alterations in both hypothalamic and pituitary function. In order to determine whether gonadotropin-releasing hormone (GnRH) gene expression is altered with aging, we compared hypothalamic preproGnRH (ppGnRH) mRNA by in situ hybridization histochemistry and GnRH peptide content in microdissected brain areas by radioimmunoassay in intact (or sham-operated) young, middle-aged, and old male rats. In addition, we determined hypothalamic-pituitary responsiveness to the removal of testicular feedback by comparing ppGnRH messenger RNA (mRNA) and gonadotropin levels in sham-operated and orchidectomized young, middle-aged, and old rats. In sham-operated rats, both the cellular ppGnRH mRNA content and the number of neurons expressing ppGnRH mRNA were lower in old compared with young and middle-aged rats. In addition, GnRH content decreased with aging in intact rats in 2 of the 3 brain areas examined, and GnRH content tended to decrease with aging in the third region. Morning serum luteinizing hormone (LH) levels were unchanged with aging, whereas follicle-stimulating hormone (FSH) was significantly increased in old compared with younger intact rats. The cellular ppGnRH mRNA content also decreased with aging in orchidectomized rats, although the number of neurons expressing ppGnRH mRNA was unchanged with aging in these rats. Within age groups, the cellular ppGnRH mRNA content was higher in orchidectomized than in sham-operated rats, though there was no effect on the number of neurons expressing GnRH. In a second study, we compared pituitary responsiveness to GnRH by measuring serum LH and FSH levels after GnRH administration in intact BN rats of different ages. The LH response to GnRH was unchanged with aging, whereas the FSH response to GnRH tended to increase with aging. Despite similar LH responses, the testosterone (T) response to GnRH declined progressively with aging. A third study assessed age-related changes in the circadian rhythm of circulating LH, T, and corticosterone (B) levels. LH levels over a 24-hour period decreased with aging and tended to be lower in the morning hours in all age groups, and circadian rhythmicity was blunted in middle-aged and old compared with young rats. T levels over 24 hours declined progressively with aging, and these levels showed a bimodal diurnal variation in young rats, a variation that was not evident in older animals. B levels over a 24-hour period were lower in old than in younger animals, and with aging, there was dampening of the amplitude of the circadian rhythm of B. Taken together, these findings suggest that secondary testicular failure in aging male BN rats is due in part to decreased GnRH gene expression rather than to decreased pituitary responsiveness to GnRH. This reduction in GnRH gene expression with aging is not dependent on testicular feedback factors. Finally, the blunted circadian rhythmicity of LH and T secretion with aging provides further evidence of altered hypothalamic regulation of gonadal hormone secretion in old animals.


Assuntos
Envelhecimento/fisiologia , Expressão Gênica , Hormônio Liberador de Gonadotropina/genética , Hormônio Liberador de Gonadotropina/fisiologia , Hipotálamo/fisiologia , Hipófise/fisiologia , Envelhecimento/metabolismo , Animais , Ritmo Circadiano , Corticosterona/sangue , Hormônio Foliculoestimulante/farmacologia , Hormônio Liberador de Gonadotropina/química , Hormônio Liberador de Gonadotropina/metabolismo , Gonadotropinas/metabolismo , Hormônio Luteinizante/sangue , Hormônio Luteinizante/farmacologia , Masculino , Fragmentos de Peptídeos/metabolismo , Precursores de Proteínas/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Endogâmicos BN , Testosterona/sangue , Testosterona/metabolismo
5.
Endocrinology ; 137(10): 4460-7, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8828508

RESUMO

Aging in man is associated with alterations in food intake (FI) and body weight (BW). To establish a model of age-related alterations in FI and BW regulation, FI and BW were determined in young (3-month-old), middle-aged (12-month-old), and old (24-month-old) male Brown Norway rats during ad libitum feeding and after 72 h of fasting. FI was reduced with aging both during ad libitum feeding and after fasting. With fasting, young rats lost more BW than older rats, but regained BW more rapidly during refeeding. To determine whether age-related impairments in FI and BW regulation are mediated by neuropeptide Y (NPY), a potent stimulator of FI, we compared arcuate nucleus prepro-NPY (ppNPY) messenger RNA (mRNA) by in situ hybridization in fasted and ad libitum-fed (fed) young, middle-aged, and old rats. ppNPY mRNA declined with aging in both fed and fasted rats. Although ppNPY mRNA increased with fasting in all age groups, this response was attenuated with aging. In conclusion, impaired FI and BW recovery after fasting is associated with reduced NPY responsiveness to fasting in aging rats. Impaired activation of the hypothalamic NPY pathway may, therefore, contribute to age-related alterations in FI and BW regulation.


Assuntos
Envelhecimento/fisiologia , Ingestão de Alimentos , Jejum , Expressão Gênica , Neuropeptídeo Y/genética , Animais , Núcleo Arqueado do Hipotálamo/metabolismo , Glicemia/análise , Peso Corporal , Insulina/sangue , Masculino , Precursores de Proteínas/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Endogâmicos BN
6.
Endocrinology ; 134(6): 2383-9, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8194464

RESUMO

Neuropeptide-Y (NPY) is thought to modulate reproductive function and food intake. NPY neuronal activity is modulated by sex steroids, and NPY secretion declines with aging. We hypothesized that reduced NPY secretion with aging is due to decreased NPY gene expression, and that this decrease is independent of testicular feedback. To test this hypothesis, arcuate nucleus (ARC) prepro-NPY (ppNPY) mRNA levels, determined by in situ hybridization, and serum testosterone levels, determined by RIA, were compared in sham-operated and orchidectomized young (3 months old), middle-aged (13 months old), and old (23 months old) male Brown Norway (BN) rats. Hybridization area and average optical density (OD) were used as indices of ARC ppNPY mRNA content. In sham-operated rats, both ppNPY mRNA hybridization area and OD decreased progressively with aging, whereas serum testosterone levels were decreased only in old, not in middle-aged or young, rats. In orchidectomized rats, ppNPY mRNA hybridization area also decreased significantly with aging, although OD did not change significantly. The ppNPY mRNA hybridization area was lower in orchidectomized than in intact young and middle-aged rats, whereas OD was unchanged by orchidectomy. Furthermore, the effects of aging and orchidectomy on ppNPY mRNA levels were not localized to a specific region of the ARC. We conclude that in the male BN rat, ARC NPY gene expression is decreased with aging independently of the effects of testicular feedback. This reduction in NPY synthetic capacity may contribute to altered reproductive function and food intake with aging.


Assuntos
Envelhecimento/metabolismo , Núcleo Arqueado do Hipotálamo/metabolismo , Expressão Gênica , Neuropeptídeo Y/genética , Testículo/fisiologia , Animais , Retroalimentação , Hibridização In Situ , Masculino , Orquiectomia , RNA Mensageiro/metabolismo , Ratos , Ratos Endogâmicos BN , Testosterona/sangue
7.
J Gerontol ; 49(2): B42-50, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8126345

RESUMO

In man, aging is associated with both primary and secondary testicular dysfunction. In contrast, most studies in male rat models of aging have demonstrated only secondary testicular failure. We previously reported that testes from aging male F344 rats secrete excessive progesterone (P), which may suppress gonadotropin secretion and confound aging studies. To determine whether the male Brown Norway (BN) rat is a more suitable aging model, trunk blood was collected from intact (sham-operated) and orchidectomized young (3 mo), middle-aged (13 mo), old (23 mo), and senescent (28-30 mo) animals. Testosterone (T), estradiol (E2), P, prolactin (PRL), luteinizing hormone (LH), and follicle-stimulating hormone (FSH) were measured by RIA. In intact rats, T levels declined with aging, while LH was unchanged, and FSH increased progressively with aging. In contrast to F344 rats, no age-related increases in P or E2 occurred, nor did PRL or other steroid hormones increase. In the absence of testicular feedback (orchidectomized rats), FSH and LH declined progressively with aging. These findings suggest that, as in men, aging male BN rats manifest both primary and secondary testicular failure, and do not exhibit decreased gonadotropin levels secondary to excessive steroid or PRL secretion. Therefore, the BN rat appears to be the best available rat model for studies of male reproductive aging.


Assuntos
Envelhecimento/fisiologia , Testículo/fisiologia , Envelhecimento/patologia , Animais , Peso Corporal , Di-Hidrotestosterona/sangue , Estradiol/sangue , Hormônio Foliculoestimulante/sangue , Hormônios Esteroides Gonadais/sangue , Gonadotropinas Hipofisárias/sangue , Hormônio Luteinizante/sangue , Masculino , Orquiectomia , Tamanho do Órgão , Prolactina/sangue , Radioimunoensaio , Ratos , Ratos Endogâmicos BN , Reprodução/fisiologia , Testículo/patologia , Testosterona/sangue
8.
Endocrinology ; 132(1): 480-2, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8419144

RESUMO

Fasting causes a decrease in serum gonadotropin and testosterone (T) levels in the male rat. We hypothesized that this fasting-induced decrease in serum gonadotropins is due to reduced GnRH gene expression. PreproGnRH mRNA (GnRH mRNA) and serum gonadotropin and T levels by RIA were compared in 90 day old male Wistar rats fed ad lib or fasted for 60 hours (n = 8/group). GnRH mRNA was quantitated by in situ hybridization and computerized image analysis in 18 anatomically matched 20 microns coronal sections from the medial preoptic area (MPOA) and diagonal band of Broca (DBB), using a 35S-labeled 48 base oligodeoxynucleotide probe complementary to rat GnRH mRNA. LH and FSH levels were lower in fasted vs fed rats (LH: 0.17 +/- 0.03 vs 0.36 +/- 0.06 ng/ml, p < 0.01; FSH: 6.7 +/- 0.5 vs 8.7 +/- 0.6 ng/ml, p < 0.05). T levels were also decreased in fasted (1.34 +/- 0.36 ng/ml) vs fed (2.21 +/- 0.30 ng/ml) rats, although this was not statistically significant (p = 0.08). In both the MPOA and DBB, the number of neurons expressing GnRH was lower in fasted vs fed rats (10.6 +/- 0.4 vs 15.8 +/- 1.2 cells/section, p < 0.001), while cellular GnRH mRNA content was unchanged with fasting (83 +/- 1 vs 80 +/- 2 grains/cell). These data support the hypothesis that in the male Wistar rat, decreased gonadotropin secretion with fasting is due, at least in part, to a reduction in GnRH gene expression.


Assuntos
Encéfalo/metabolismo , Jejum/fisiologia , Expressão Gênica , Hormônio Liberador de Gonadotropina/genética , Animais , Hormônio Foliculoestimulante/sangue , Hormônio Luteinizante/sangue , Masculino , Área Pré-Óptica/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Testosterona/sangue
9.
J Gerontol ; 47(5): B164-70, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1512426

RESUMO

Previous studies have inconsistently reported elevated sex steroid levels in aging male F344 rats, which frequently develop testicular Leydig cell tumors. The aims of this study were to characterize circulating steroid levels and to determine the in vivo source and functional significance of altered steroid secretion in these animals. Progesterone (P) and to a lesser extent estradiol (E2) levels were increased, while gonadotropins and testosterone (T) were decreased, in intact 24-mo-old compared to 12-mo-old rats. P levels were inversely correlated with gonadotropins and T. All old rats demonstrated Leydig cell hyperplasia or tumors. After orchidectomy, P levels were markedly decreased. Gonadotropin levels were similar in orchidectomized 24-mo compared to 3-mo-old rats. We conclude that the testis is the source of excessive P and E2 secretion in vivo in old F344 rats. Increased P (or E2) negative feedback may contribute to the suppression of gonadotropins and reproductive function in aging male F344 rats. Finally, excessive P secretion may be a confounding pathological variable in aging studies using this rat model.


Assuntos
Envelhecimento/metabolismo , Corticosterona/sangue , Estradiol/sangue , Progesterona/metabolismo , Testículo/metabolismo , Testosterona/sangue , 17-alfa-Hidroxiprogesterona , Envelhecimento/sangue , Androstenodiona/sangue , Animais , Hormônio Foliculoestimulante/sangue , Hidroxiprogesteronas/sangue , Hiperplasia , Hipertrofia , Células Intersticiais do Testículo/patologia , Hormônio Luteinizante/sangue , Masculino , Orquiectomia , Progesterona/sangue , Ratos , Ratos Endogâmicos F344 , Testículo/patologia
10.
Endocrinology ; 129(5): 2442-50, 1991 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1935778

RESUMO

In the male rat, age-associated reproductive decline is thought to be due in part to diminished GnRH secretion. We tested the hypothesis that the age-related decrease in GnRH secretion is due to decreased GnRH gene expression by comparing GnRH mRNA and peptide content in the anterior forebrain of intact young and old male rats. Since sex steroids modulate GnRH secretion, we also determined hypothalamic-pituitary responsiveness to removal of testicular feedback by comparing GnRH mRNA and gonadotropin levels in intact and orchidectomized young and old rats. In an initial study, 10 20-micron coronal sections from the medial preoptic area (MPOA) were anatomically matched and compared in intact young (3-month-old) and old (24-month-old) male F344 rats (n = 5/group). In another group of young and old male rats (n = 8-12/group), animals were randomly assigned to be either orchidectomized or sham operated. Rats were killed 21 days after surgery, and comparisons were made in 12 anatomically matched sections of MPOA and 4 matched sections of diagonal band of Broca. In both studies, GnRH mRNA was quantitated by in situ hybridization, using a 35S-labeled oligodeoxynucleotide probe complementary to rat prepro-GnRH mRNA and a computerized image analysis system. In a third study, GnRH content was measured by RIA in microdissected regions of the arcuate nucleus and median eminence in intact 3- and 24-month-old male rats (n = 10 and 8, respectively). Serum LH, FSH, and testosterone (T) levels were measured by RIA in trunk blood of all animals. The number of neurons expressing the GnRH gene in the MPOA was significantly lower in sham-operated old rats (mean +/- SEM, 10.5 +/- 0.5 cells/section) than in young rats (13.7 +/- 0.7 cells/section; P less than 0.01), while cellular GnRH mRNA content was unchanged with age (103 +/- 1 vs. 103 +/- 2 grains/cell). Similar results were obtained in intact old and young rats. GnRH peptide content was significantly decreased in the arcuate nucleus of intact old (0.5 +/- 0.08 ng/mg protein) compared to young animals (2.3 +/- 0.7 ng/mg protein; P less than 0.05), with a trend toward a decrease in the median eminence of old (53 +/- 2 ng/mg protein) vs. young rats (69 +/- 7 ng/mg protein; P = 0.06).(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Envelhecimento/fisiologia , Expressão Gênica , Hormônio Liberador de Gonadotropina/genética , Gonadotropinas/sangue , Área Pré-Óptica/fisiologia , Testículo/fisiologia , Animais , Contagem de Células , Retroalimentação , Hormônio Liberador de Gonadotropina/análise , Masculino , Orquiectomia , Área Pré-Óptica/química , RNA Mensageiro/análise , Ratos , Ratos Endogâmicos F344 , Ratos Endogâmicos
11.
Neurobiol Aging ; 12(2): 113-21, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1711159

RESUMO

The decline in reproductive function with aging is due in part to decreased gonadotropin-releasing hormone (GnRH) secretion. beta-Endorphin (beta E), an endogenous opioid peptide derived from proopiomelanocortin (POMC), is thought to exert a tonic inhibitory effect upon hypothalamic GnRH secretion. We tested the hypothesis that the age-related decrease in GnRH secretion in male rats is due to increased beta E synthesis, by comparing POMC mRNA levels in the arcuate nucleus (ARC) of intact young, middle-aged and old male rats. In an initial study (Study 1), sixteen 20-microns coronal sections each from the ARC of 3- (n = 5) and 23-month-old (n = 4) male Fischer 344 rats were anatomically matched and analyzed. In a second study (Study 2), four anatomically matched sections of caudal arcuate nucleus from 3- (n = 4), 11- (n = 7) and 23-month-old (n = 5) male rats were compared. POMC mRNA levels were quantitated by in situ hybridization histochemistry, using a 35S-labeled oligodeoxynucleotide probe complementary to a portion of rat POMC cDNA and computerized image analysis. The number of grains per cell and cells per section were used as indices of cellular POMC mRNA content and the number of neurons expressing the POMC gene, respectively. Cellular POMC mRNA content was significantly lower in old compared to young animals (Study 1: 54 +/- 3 vs. 74 +/- 2 grains/cell, p less than 0.01; Study 2: 59 +/- 2 vs. 71 +/- 2 grains/cell, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Envelhecimento/metabolismo , Expressão Gênica/fisiologia , Hipotálamo/metabolismo , Pró-Opiomelanocortina/biossíntese , Animais , Autorradiografia , Hormônio Liberador de Gonadotropina/metabolismo , Histocitoquímica , Hormônio Luteinizante/sangue , Masculino , Hibridização de Ácido Nucleico , Pró-Opiomelanocortina/genética , RNA Mensageiro/metabolismo , Radioimunoensaio , Ratos , Ratos Endogâmicos F344 , Coloração e Rotulagem , Testosterona/sangue , beta-Endorfina/fisiologia
12.
Immunology ; 38(1): 191-4, 1979 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-315915

RESUMO

Carrier-primed helper activity enhancing anti-hapten (TNP-) responses in young adult Xenopus laevis reached peak levels 2-4 days after a low dose challenge (0.005% RBC) of unconjugated carrier. It fell quickly to negligible levels by 10 days. Adult thymectomized (ATx) animals were consistently unable to generate substantial levels of hapten-specific antigen-binding spleen cell (ABC) activity. Since ATx does not severely reduce splenic ABC responses to the high dose (10% RBC) of carrier used for hapten challenge, the results suggested a role for Xenopus adult thymus in carrier-specific enhancement of an anti-hapten response.


Assuntos
Linfócitos T/imunologia , Timectomia , Animais , Eritrócitos/imunologia , Haptenos/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Baço/imunologia , Fatores de Tempo , Trinitrobenzenos/imunologia , Xenopus
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