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1.
Osteoporos Int ; 32(11): 2371-2375, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34080044

RESUMO

The trabecular bone score (TBS) is an indirect measure of vertebral bone microarchitecture. Our objective was to examine the effect of testosterone treatment on TBS. One hundred and ninety-seven hypogonadal men were randomized to testosterone or placebo. After 12 months, there was no difference in the changes in TBS by randomized group. INTRODUCTION: In the Bone Trial of the Testosterone Trials, testosterone treatment increased trabecular volumetric bone mineral density (vBMD) and increased estimated bone strength as determined by finite element analysis. The trabecular bone score (TBS) is an indirect measure of vertebral bone microarchitecture. TBS predicts fracture independent of lumbar spine areal (a) BMD. The objective of this study was to examine the effect of testosterone treatment on TBS compared to its effects on vBMD and aBMD. METHODS: Two hundred and eleven men were enrolled in the Bone Trial of the Testosterone Trials. Of these, 197 men had 2 repeat TBS and vBMD measurements; 105 men were allocated to receive testosterone, and 92 men to placebo for 1 year. TBS, aBMD, and vBMD were assessed at baseline and month 12. RESULTS: There was no difference in the percent change in TBS by randomized group: 1.6% (95% confidence intervals (CI) 0.2-3.9) in the testosterone group and 1.4% (95% CI -0.2, 3.1) in the placebo group. In contrast, vBMD increased by 6% (95% CI 4.5-7.5) in the testosterone group compared to 0.4% (95% CI -1.65-0.88) in the placebo groups. CONCLUSIONS: TBS is not clinically useful in monitoring the 1-year effect of testosterone treatment on bone structure in older hypogonadal men.


Assuntos
Osso Esponjoso , Testosterona , Absorciometria de Fóton , Idoso , Densidade Óssea , Osso Esponjoso/diagnóstico por imagem , Humanos , Vértebras Lombares , Masculino
2.
J Prev Alzheimers Dis ; 6(1): 2-15, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30569080

RESUMO

Scientific evidence collected over the past 4 decades suggests that a loss of cholinergic innervation in the cerebral cortex of patients with Alzheimer's disease is an early pathogenic event correlated with cognitive impairment. This evidence led to the formulation of the "Cholinergic Hypothesis of AD" and the development of cholinesterase inhibitor therapies. Although approved only as symptomatic therapies, recent studies suggest that long-term use of these drugs may also have disease-modifying benefits. A Cholinergic System Workgroup reassessed the role of the cholinergic system on AD pathogenesis in light of recent data, including neuroimaging data charting the progression of neurodegeneration in the cholinergic system and suggesting that cholinergic therapy may slow brain atrophy. Other pathways that contribute to cholinergic synaptic loss and their effect on cognitive impairment in AD were also reviewed. These studies indicate that the cholinergic system as one of several interacting systems failures that contribute to AD pathogenesis.


Assuntos
Doença de Alzheimer , Colinérgicos/uso terapêutico , Neurônios Colinérgicos/patologia , Neurônios Colinérgicos/fisiologia , Pesquisa Translacional Biomédica , Envelhecimento/fisiologia , Doença de Alzheimer/complicações , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/patologia , Doença de Alzheimer/fisiopatologia , Encéfalo/patologia , Disfunção Cognitiva/complicações , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/fisiopatologia , Demência/patologia , Demência/fisiopatologia , Humanos
3.
Alzheimers Dement (N Y) ; 2(1): 23-29, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27019867

RESUMO

INTRODUCTION: This survey characterizes viewpoints of cognitively intact at-risk participants in an Alzheimer prevention registry if given the opportunity to learn their genetic and amyloid PET status. METHODS: 207 participants were offered a 25-item survey. They were asked if they wished to know their ApoE and amyloid PET status, and if so, reasons for wanting to know, or not, and the effects of such information on life plans. RESULTS: 164 (79.2%) of registrants completed the survey. Among those who were unaware of their ApoE or amyloid PET results, 80% desired to know this information. The most common reasons for wanting disclosure were to participate in research, to arrange personal affairs, to prepare family for illness, and to move life plans closer into the future. When asked if disclosure would help with making plans to end one's life when starting to lose their memory, 12.7% vs. 11.5% responded yes for ApoE and amyloid PET disclosures, respectively. Disclosure of these test results, if required for participation in a clinical trial, would make 15% of people less likely to participate. Likelihood of participation in prevention research and the desire to know test results were not related to scores on brief tests of knowledge about the tests. DISCUSSION: These results suggest that stakeholders in AD prevention research generally wish to know biological test information about their risk for developing AD to assist in making life plans.

4.
Mol Psychiatry ; 20(11): 1322-8, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25288138

RESUMO

Accumulation of ß-amyloid (Aß) in the brain is associated with memory decline in healthy individuals as a prelude to Alzheimer's disease (AD). Genetic factors may moderate this decline. We examined the role of apolipoprotein E (ɛ4 carrier[ɛ4(+)], ɛ4 non-carrier[ɛ4(-)]) and brain-derived neurotrophic factor (BDNF(Val/Val), BDNF(Met)) in the extent to which they moderate Aß-related memory decline. Healthy adults (n=333, Mage=70 years) enrolled in the Australian Imaging, Biomarkers and Lifestyle study underwent Aß neuroimaging. Neuropsychological assessments were conducted at baseline, 18-, 36- and 54-month follow-ups. Aß positron emission tomography neuroimaging was used to classify participants as Aß(-) or Aß(+). Relative to Aß(-)ɛ4(-), Aß(+)ɛ4(+) individuals showed significantly faster rates of cognitive decline over 54 months across all domains (d=0.40-1.22), while Aß(+)ɛ4(-) individuals showed significantly faster decline only on verbal episodic memory (EM). There were no differences in rates of cognitive change between Aß(-)ɛ4(-) and Aß(-)ɛ4(+) groups. Among Aß(+) individuals, ɛ4(+)/BDNF(Met) participants showed a significantly faster rate of decline on verbal and visual EM, and language over 54 months compared with ɛ4(-)/BDNF(Val/Val) participants (d=0.90-1.02). At least two genetic loci affect the rate of Aß-related cognitive decline. Aß(+)ɛ4(+)/BDNF(Met) individuals can expect to show clinically significant memory impairment after 3 years, whereas Aß(+)ɛ4(+)/BDNF(Val/Val) individuals can expect a similar degree of impairment after 10 years. Little decline over 54 months was observed in the Aß(-) and Aß(+) ɛ4(-) groups, irrespective of BDNF status. These data raise important prognostic issues in managing preclinical AD, and should be considered in designing secondary preventative clinical trials.


Assuntos
Doença de Alzheimer/complicações , Peptídeos beta-Amiloides/metabolismo , Apolipoproteínas E/genética , Fator Neurotrófico Derivado do Encéfalo/genética , Transtornos Cognitivos , Polimorfismo de Nucleotídeo Único/genética , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/genética , Compostos de Anilina/metabolismo , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/genética , Transtornos Cognitivos/metabolismo , Feminino , Seguimentos , Engenharia Genética , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Tomografia por Emissão de Pósitrons , Escalas de Graduação Psiquiátrica , Tiazóis/metabolismo
5.
Analyst ; 139(22): 5927-35, 2014 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-25252650

RESUMO

Resolving weak spectral variations in the dynamic response of materials that are either dominated or excited by stochastic processes remains a challenge. Responses that are thermal in origin are particularly relevant examples due to the delocalized nature of heat. Despite its inherent properties in dealing with stochastic processes, the Karhunen-Loève expansion has not been fully exploited in measurement of systems that are driven solely by random forces or can exhibit large thermally driven random fluctuations. Here, we present experimental results and analysis of the archetypes (a) the resonant excitation and transient response of an atomic force microscope probe by the ambient random fluctuations and nanoscale photothermal sample response, and (b) the photothermally scattered photons in pump-probe spectroscopy. In each case, the dynamic process is represented as an infinite series with random coefficients to obtain pertinent frequency shifts and spectral peaks and demonstrate spectral enhancement for a set of compounds including the spectrally complex biomass. The considered cases find important applications in nanoscale material characterization, biosensing, and spectral identification of biological and chemical agents.


Assuntos
Ruído , Análise Espectral/métodos , Microscopia de Força Atômica
6.
Osteoporos Int ; 25(3): 973-82, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24221453

RESUMO

SUMMARY: We investigated the association of postmenopausal vertebral deformities and fractures with bone parameters derived from distal extremities using MRI and pQCT. Distal extremity measures showed variable degrees of association with vertebral deformities and fractures, highlighting the systemic nature of postmenopausal bone loss. INTRODUCTION: Prevalent vertebral deformities and fractures are known to predict incident further fractures. However, the association of distal extremity measures and vertebral deformities in postmenopausal women has not been fully established. METHODS: This study involved 98 postmenopausal women (age range 60-88 years, mean 70 years) with DXA BMD T-scores at either the hip or spine in the range of -1.5 to -3.5. Wedge, biconcavity, and crush deformities were computed on the basis of spine MRI. Vertebral fractures were assessed using Eastell's criterion. Distal tibia and radius stiffness was computed using MRI-based finite element analysis. BMD at the distal extremities were obtained using pQCT. RESULTS: Several distal extremity MRI and pQCT measures showed negative association with vertebral deformity on the basis of single parameter correlation (r up to 0.67) and two-parameter regression (r up to 0.76) models involving MRI stiffness and pQCT BMD. Subjects who had at least one prevalent vertebral fracture showed decreased MRI stiffness (up to 17.9 %) and pQCT density (up to 34.2 %) at the distal extremities compared to the non-fracture group. DXA lumbar spine BMD T-score was not associated with vertebral deformities. CONCLUSIONS: The association between vertebral deformities and distal extremity measures supports the notion of postmenopausal osteoporosis as a systemic phenomenon.


Assuntos
Osteoporose Pós-Menopausa/complicações , Fraturas por Osteoporose/etiologia , Rádio (Anatomia)/patologia , Curvaturas da Coluna Vertebral/etiologia , Fraturas da Coluna Vertebral/etiologia , Tíbia/patologia , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea/fisiologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/diagnóstico , Osteoporose Pós-Menopausa/fisiopatologia , Fraturas por Osteoporose/fisiopatologia , Rádio (Anatomia)/diagnóstico por imagem , Rádio (Anatomia)/fisiopatologia , Estudos Retrospectivos , Curvaturas da Coluna Vertebral/fisiopatologia , Fraturas da Coluna Vertebral/fisiopatologia , Tíbia/diagnóstico por imagem , Tíbia/fisiopatologia , Tomografia Computadorizada por Raios X/métodos
7.
Andrology ; 1(1): 24-8, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23258626

RESUMO

The stimulatory effects of testosterone on erythropoiesis are very well known, but the mechanisms underlying the erythropoietic action of testosterone are still poorly understood, although erythropoietin has long been considered a potential mediator. A total of 108 healthy men >65 years old with serum testosterone concentration <475 ng/dL were recruited by direct mailings to alumni of the University of Pennsylvania and Temple University, and randomized to receive a 60-cm(2) testosterone or placebo patch for 36 months. Ninety-six subjects completed the trial. We used information and stored serum specimens from this trial to test the hypothesis that increasing testosterone increases haemoglobin by stimulating erythropoietin production. We used information of 67 men, 43 in the testosterone group and 24 in the placebo group who had banked specimens available for assays of testosterone, haemoglobin and erythropoietin at baseline and after 36 months. The original randomized clinical study was primarily designed to verify the effects of testosterone on bone mineral density. The primary outcome of this report was to investigate whether or not transdermal testosterone increases haemoglobin by increasing erythropoietin levels. The mean age ± SD of the 67 subjects at baseline was 71.8 ± 4.9 years. Testosterone replacement therapy for 36 months, as compared with placebo, induced a significant increase in haemoglobin (0.86 ± 0.31 g/dL, p = 0.01), but no change in erythropoietin levels (-0.24 ± 2.16 mIU/mL, p = 0.91). Included time-varying measure of erythropoietin did not significantly account for the effect of testosterone on haemoglobin (Treatment-by-time: ß = 0.93, SE = 0.33, p = 0.01). No serious adverse effect was observed. Transdermal testosterone treatment of older men for 36 months significantly increased haemoglobin, but not erythropoietin levels. The haematopoietic effect of testosterone does not appear to be mediated by stimulation of erythropoietin production.


Assuntos
Eritropoetina/sangue , Hematopoese/efeitos dos fármacos , Terapia de Reposição Hormonal , Testosterona/administração & dosagem , Administração Cutânea , Idoso , Biomarcadores/sangue , Método Duplo-Cego , Hemoglobinas/metabolismo , Humanos , Masculino , Philadelphia , Testosterona/sangue , Testosterona/deficiência , Fatores de Tempo , Adesivo Transdérmico , Resultado do Tratamento , Regulação para Cima
8.
Curr Alzheimer Res ; 8(2): 203-12, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21222604

RESUMO

BACKGROUND: EHT0202 (etazolate hydrochloride) is a new compound exhibiting both potential disease-modifying and symptomatic treatment properties in Alzheimer's Disease increasing alpha-secretase activity and sAPP alpha secretion, as well as acting as a GABA-A receptor modulator and as a PDE-4 inhibitor. METHODS: This pilot, randomized, double-blind, placebo-controlled, parallel group, multicentre, Phase IIA study was conducted in 159 randomized patients suffering from mild to moderate Alzheimer's Disease. EHT0202 (40 or 80 mg bid) or placebo was administered as adjunctive therapy to one acetylcholinesterase inhibitor over a 3-month period. This study was designed to assess the clinical safety and tolerability of EHT0202 as a primary objective, with secondary endpoints (cognitive function, daily living activities, behaviour, caregiver burden and global functioning) included to explore clinical efficacy of EHT0202 versus placebo. RESULTS: EHT0202 was shown to be safe and generally well tolerated. Dose-dependent numbers of early withdrawal and central nervous system related adverse events were observed. As expected, since the study was not powered and not designed to show drug efficacy, and except for ratings on the ADCS-ADL scale, no significant differences were seen between treatment groups. CONCLUSIONS: These first encouraging safety results do support further development of EHT0202 in order to assess its clinical efficacy and to confirm its tolerability in a larger cohort of Alzheimer patients and for a longer period.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Etazolato/efeitos adversos , Inibidores de Fosfodiesterase/efeitos adversos , Idoso , Método Duplo-Cego , Feminino , Humanos , Masculino , Projetos Piloto , Fatores de Tempo
9.
Neurourol Urodyn ; 30(1): 183-7, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21058363

RESUMO

AIMS: In healthy adults, voluntary inhibition of micturition is associated with an increasing sensation in the urge to void and pain, and acute pain has been associated with transient deterioration in aspects of cognitive function. METHODS: Eight healthy young adults consumed 250 ml of water every 15 min until they could no longer inhibit voiding. Performance on standardized measures of cognitive function was measured at hourly intervals which were classified as baseline, when individuals reported an increase in the urge to void, a strong increase in the urge to void, an extreme increase in the urge to void and postmicturition. RESULTS: Sensations of the urge to void and pain increased with time of inhibition of urge to void and with amount of water consumed. Having an extreme urge to void exerted a large negative effect on attentional and working memory functions (d>0.8). These cognitive functions returned to normal levels after micturition. CONCLUSION: The magnitude of decline in cognitive function associated with an extreme urge to void was as large and equivalent or greater than the cognitive deterioration observed for conditions known to be associated with increased accident risk.


Assuntos
Cognição , Ingestão de Líquidos , Sensação/fisiologia , Bexiga Urinária/fisiologia , Micção/fisiologia , Adulto , Atenção , Feminino , Humanos , Masculino , Memória de Curto Prazo , Pessoa de Meia-Idade , Testes Neuropsicológicos , Dor , Fatores de Tempo
10.
Neurology ; 74(6): 502-6, 2010 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-20142617

RESUMO

OBJECTIVE: Idiopathic peripheral neuropathy is common and likely due to genetic factors that are not detectable using standard linkage analysis. We initiated a candidate gene approach to study the genetic influence of the small heat shock protein (sHSP) gene family on an axonal motor and motor/sensory neuropathy patient population. METHODS: The promoter region and all exonic and intronic sequences of the 10 sHSP genes (HSPB1-HSPB10) were screened in a cohort of presumed nonacquired, axonal motor and motor/sensory neuropathy patients seen at the Ohio State University Neuromuscular Clinic. RESULTS: A missense mutation in the gene encoding small heat shock protein B3 (HSPB3, also called HSP27, protein 3) was discovered in 2 siblings with an asymmetric axonal motor neuropathy. Electrophysiologic studies revealed an axonal, predominantly motor, length-dependent neuropathy. The mutation, HSPB3(R7S), is located in the N-terminal domain and involves the loss of a conserved arginine. CONCLUSIONS: The discovery of an HSPB3 mutation associated with an axonal motor neuropathy using a candidate gene approach supports the notion that the small heat shock protein gene family coordinately plays an important role in motor neuron viability.


Assuntos
Proteínas de Choque Térmico/genética , Neuropatia Hereditária Motora e Sensorial/genética , Mutação/genética , Estudos de Coortes , Análise Mutacional de DNA/métodos , Saúde da Família , Feminino , Predisposição Genética para Doença , Humanos , Pessoa de Meia-Idade , Projetos Piloto
11.
J Nutr Health Aging ; 13(3): 268-73, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19262966

RESUMO

OBJECTIVES: Change in cognitive function in response to a pharmacologic challenge can be observed with greater sensitivity by employing cognitive tests with optimal psychometric properties and a statistical approach that more accurately accounts for individual variability in performance. To demonstrate this approach we examined the cognitive effects of a single acute dose administration of an acetylcholinesterase inhibitor, donepezil, in healthy older adults and in older adults with mild Alzheimer's disease (AD). DESIGN: Placebo-controlled crossover study with three separate testing days: baseline, placebo, and donepezil, with assessments at baseline, and 1-, 2-, 3-, 6-, and 8-hrs post-dosing on each day. SETTING: Early phase I clinical trial. PARTICIPANTS: 15 healthy older adults; 14 older adults with mild Alzheimer's disease. INTERVENTION: Single acute dose of 5mg donepezil. MEASUREMENTS: Performance on the Groton Maze Learning Test (GMLT), a computerized neuropsychological measure of spatial working memory and error monitoring. RESULTS: A single acute dose of donepezil improved GMLT performance in healthy older adults (effect size: 0.83 at 6 hrs post-dosing) and older adults with mild AD (effect size: 0.58 at 3 hrs post-dosing). CONCLUSION: The GMLT detected cognitive improvement following a single, acute dose administration of donepezil in healthy older adults and older adults with mild AD. The choice of cognitive tests designed for repeated administration, as well as an analytic approach that emphasizes individual-level change in cognitive function, provides a sensitive approach to detecting central nervous system drug penetration and activity of cognitive-enhancing agents.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Inibidores da Colinesterase/uso terapêutico , Transtornos Cognitivos/tratamento farmacológico , Cognição/efeitos dos fármacos , Indanos/uso terapêutico , Piperidinas/uso terapêutico , Idoso , Doença de Alzheimer/complicações , Inibidores da Colinesterase/administração & dosagem , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/etiologia , Estudos Cross-Over , Donepezila , Método Duplo-Cego , Humanos , Indanos/administração & dosagem , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Memória de Curto Prazo/efeitos dos fármacos , Pessoa de Meia-Idade , Testes Neuropsicológicos/estatística & dados numéricos , Piperidinas/administração & dosagem , Psicometria , Reprodutibilidade dos Testes , Projetos de Pesquisa , Sensibilidade e Especificidade
12.
Int J Clin Pharmacol Ther ; 47(2): 111-9, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19203567

RESUMO

UNLABELLED: Phenotyping intestinal and hepatic cytochrome P450 (CYP) 3A activity with oral midazolam can be limited by midazolam-induced central nervous system (CNS) side effects. Determining methods to minimize CNS side effects optimizes use of midazolam as a CYP3A probe. OBJECTIVE: The objective of this study was to determine the effect of intravenous (i.v.) flumazenil on midazolam apparent oral clearance (a surrogate marker of CYP3A activity). Midazolam pharmacodynamics were also evaluated. METHODS: This was a randomized, double-blind, placebo-controlled, single-dose, two-way crossover study. 16 healthy volunteers (8 women) were concomitantly administered i.v. flumazenil 0.005 mg/kg or i.v. placebo and oral midazolam 0.075 mg/kg. Blood samples were obtained to determine midazolam and flumazenil plasma concentrations. Bioequivalence was assessed by determining geometric mean ratios (GMR) and 90% confidence intervals (90% CI). Baseline and post dose digit symbol substitution tests (DSST), Groton maze learning tests (GMLT), and Stanford sleepiness scales (SSS) were conducted. RESULTS: Apparent oral clearance was 2,030 +/- 651 and 1,939 +/- 658 ml/min for the midazolam plus flumazenil and midazolam plus placebo groups. Equivalence in midazolam apparent oral clearance was observed (%GMR flumazenil/placebo, 90% CI 104.8, 94 - 116.6%). Flumazenil partially attenuated oral midazolam pharmacodynamics. Exploratory post hoc analyses revealed that midazolam exposure was 1.9-fold higher in men compared to women. CONCLUSION: i.v. flumazenil can be used in conjunction with oral midazolam for CYP3A phenotyping.


Assuntos
Citocromo P-450 CYP3A/efeitos dos fármacos , Flumazenil/farmacologia , Moduladores GABAérgicos/farmacologia , Midazolam/farmacocinética , Administração Oral , Adulto , Estudos Cross-Over , Citocromo P-450 CYP3A/metabolismo , Método Duplo-Cego , Interações Medicamentosas , Feminino , Moduladores GABAérgicos/farmacocinética , Humanos , Injeções Intravenosas , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Midazolam/farmacologia , Pessoa de Meia-Idade , Testes Neuropsicológicos , Fenótipo , Fatores Sexuais , Equivalência Terapêutica
13.
Am J Med ; 111(4): 255-60, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11566454

RESUMO

PURPOSE: Because the effects of androgen replacement on lipoprotein levels are uncertain, we sought to determine the effect of transdermal testosterone treatment on serum lipid and apolipoprotein levels in elderly men. SUBJECTS AND METHODS: One hundred and eight healthy men more than 65 years of age who had serum testosterone concentrations >1 SD below the mean for young men were randomly assigned to receive either testosterone (54 men; 6 mg/day) or placebo (54 men) transdermally in a double-blind fashion for 36 months. Serum concentrations of lipids and apolipoproteins were measured, and cardiovascular events recorded. RESULTS: Serum total cholesterol concentrations decreased in both the testosterone-treated men and placebo-treated men, but the 3-year mean (+/- SD) decreases in the two groups (testosterone treated, -17 +/- 29 mg/dL; placebo treated, -12 +/- 38 mg/dL) were not significantly different from each other (P = 0.4). Similarly, serum low-density lipoprotein (LDL) cholesterol levels decreased in both treatment groups, but the decreases in the two groups (testosterone treated, -16 +/- 24 mg/dL; placebo treated, -16 +/- 33 mg/dL) were similar (P = 1.0). Levels of high-density lipoprotein (HDL) cholesterol, triglycerides, and apolipoproteins A-I and B did not change. Lipoprotein(a) levels increased in both groups by similar amounts (testosterone treated, 3 +/- 9 mg/dL; placebo treated, 4 +/- 6 mg/dL; P = 1.0). The number of cardiovascular events was small and did not differ significantly between the testosterone-treated men (9 events) and the placebo-treated men (5 events) during the 3-year study (relative risk = 1.8; 95% confidence interval: 0.7 to 5.0). CONCLUSIONS: As compared with placebo, transdermal testosterone treatment of healthy elderly men for 3 years did not affect any of the lipid or apolipoprotein parameters that we measured. The effect of testosterone treatment on cardiovascular events was unclear, because the number of events was small.


Assuntos
Apolipoproteínas/sangue , Lipídeos/sangue , Testosterona/uso terapêutico , Administração Cutânea , Idoso , Densidade Óssea/efeitos dos fármacos , Método Duplo-Cego , Ensaio de Imunoadsorção Enzimática , Humanos , Masculino , Músculos/efeitos dos fármacos , Estatísticas não Paramétricas , Testosterona/sangue , Fatores de Tempo
14.
Brain Cogn ; 46(1-2): 276-9, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11527348

RESUMO

The parrot appears to provide a potentially unique animal model of handedness in humans, but few (if any) observational studies of early postnatal development of postural/motor asymmetries have been published. We studied three African Grey hatchlings, raised without human physical contact, for the first 5 months of life. All three animals failed to show consistent postural and/or motor asymmetries until the end of the 4 postnatal week. These results appear to be comparable to data from prior studies with human infants. Delayed development of lateral motor and/or postural preferences may represent an evolutionarily adaptive strategy for altricial animals.


Assuntos
Encéfalo/fisiologia , Comportamento de Escolha/fisiologia , Lateralidade Funcional/fisiologia , Destreza Motora/fisiologia , Papagaios/fisiologia , Animais , Animais Recém-Nascidos/fisiologia , Comportamento Animal/fisiologia , Projetos Piloto , Postura/fisiologia
15.
Brain Cogn ; 46(1-2): 279-84, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11527349

RESUMO

Despite frequent use of the Paced Auditory Serial Addition Test (PASAT; Gronwall, 1977) for examining information processing speed (IPS) deficits in multiple sclerosis (MS), prior literature on the relationship between PASAT performance and severity of brain disease has been contradictory. In the present study, we found that PASAT performance is moderately well correlated with the total area of sclerotic brain lesions in MS patients only if a modified scoring method (mean "dyad" score; Snyder et al., 1993), but not the standard scoring method, is applied. We conclude that the PASAT remains a useful measure of IPS in MS, if a flaw in the typical scoring technique for this test is corrected. In our sample of 41 MS patients, for every one point decrease in mean dyad score, total lesion area increased by 364.08 mm2 on average, after controlling for age, sex, and education. IPS deficits are more severe for patients with greater brain disease, due to increased disruption of the white matter pathways that likely support the parallel distributed processing of complex information by geographically distant brain regions.


Assuntos
Transtornos da Percepção Auditiva/diagnóstico , Transtornos da Percepção Auditiva/etiologia , Encéfalo/patologia , Encéfalo/fisiopatologia , Esclerose Múltipla , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/complicações , Esclerose Múltipla/patologia , Esclerose Múltipla/fisiopatologia , Testes Neuropsicológicos , Tempo de Reação , Índice de Gravidade de Doença
16.
J Bone Miner Res ; 16(8): 1520-31, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11499875

RESUMO

Osteoporosis is a disease characterized by bone volume loss and architectural deterioration. The majority of work aimed at evaluating the structural implications of the disease has been performed based on stereologic analysis of histomorphometric sections. Only recently noninvasive imaging methods have emerged that provide sufficient resolution to resolve individual trabeculae. In this article, we apply digital topological analysis (DTA) to magnetic resonance microimages (mu-MRI) of the radius obtained at 137 x 137 x 350 microm3 voxel size in a cohort of 79 women of widely varying bone mineral density (BMD) and vertebral deformity status. DTA is a new method that allows unambiguous determination of the three-dimensional (3D) topology of each voxel in a trabecular bone network. The analysis involves generation of a bone volume fraction map, which is subjected to subvoxel processing to alleviate partial volume blurring, followed by thresholding and skeletonization. The skeletonized images contain only surfaces, profiles, curves, and their mutual junctions as the remnants of trabecular plates and rods after skeletonization. DTA parameters were compared with integral BMD in the lumbar spine and femur as well as MR-derived bone volume fraction (BV/TV). Vertebral deformities were determined based on sagittal MRIs of the spine with a semiautomatic method and the number of deformities counted after threshold setting. DTA structural indices were found the strongest discriminators of subjects with deformities from those without deformities. Subjects with deformities (n = 29) had lower topological surface (SURF) density (p < 0.0005) and surface-to-curve ratio (SCR; a measure of the ratio of platelike to rodlike trabeculae; p < 0.0005) than those without. Profile interior (PI) density, a measure of intact trabecular rods, was also lower in the deformity group (p < 0.0001). These data provide the first in vivo evidence for the structural implications inherent in postmenopausal osteoporosis accompanying bone loss, that is, the conversion of trabecular plates to rods and disruption of rods due to repeated osteoclastic resorption.


Assuntos
Fêmur/patologia , Vértebras Lombares/patologia , Osteoporose/patologia , Adulto , Idoso , Densidade Óssea , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Fatores de Risco
17.
J Hist Neurosci ; 10(2): 163-72, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11512427

RESUMO

Epilepsy is a major public health threat in the developing world, with much higher prevalence and incidence rates than those observed in developed countries. At present, one of the most common causes for epilepsy worldwide is the parasitic worm, Taenia solium, and the associated neurocysticercosis (NCC) that may often result from this infestation. Worm infestation was already recognized as a cause of epilepsy by the middle of the 18th century. Helminths and their effects on health were a daily medical concern in the 18th and 19th centuries--with prevailing views ranging from the beneficial effects of the presence of adult worms in the gut, to considering them as culprits for a wide variety of diseases. A number of cases followed longitudinally by various nineteenth-century French physicians showed that there was good reason to believe that the verminous influence on seizures was real, as the expulsion of the T. solium often coincided with a notable amelioration of symptoms. Several theories were proposed to account for how the worms could lead to Epilepsia nervosa, including notions of competition for nutritional resources between the host and the parasite, and irritation of the medulla and of peripheral nerve endings predisposing to epileptiform episodes. Recently, after almost a century of quiet, interest in the neurological effects of helminths has been rekindled, due in part to the growing number of cases in the United States with NCC-related neurological disorders. In this article, we review the history of our understanding of the relationship between seizure disorders and parasitic worms, and we relate this history to contemporary epidemiologic and public health issues in developing countries.


Assuntos
Epilepsia/história , Neurocisticercose/história , Países em Desenvolvimento , Epilepsia/parasitologia , História do Século XVII , História do Século XVIII , História do Século XIX , História do Século XX , Humanos , Neurocisticercose/complicações , Convulsões/história , Teníase/complicações , Teníase/história , Água/efeitos adversos
19.
Clin Endocrinol (Oxf) ; 54(6): 739-50, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11422108

RESUMO

OBJECTIVE: Androgen replacement has been reported to increase bone mineral density (BMD) in hypogonadal men. We studied the effects of 6 months of treatment with a new transdermal testosterone (T) gel preparation on bone turnover markers and BMD. DESIGN: This was a prospective, randomized, multicentre, parallel clinical trial where 227 hypogonadal men, mean age 51 years (range: 19-68 years) were studied in 16 academic and research institutions in the USA. Subjects were randomized to apply 1% T gel containing 50 or 100 mg T (delivering approximately 5-10 mg T/day) or two T patches (delivering 5 mg T/day) transdermally for 90 days. At day 91, depending on the serum T concentration, the T gel dose was adjusted upward or downward to 75 mg T/day until day 180. No dose adjustment occurred in the T patch group. MEASUREMENTS: Serum T, free T and oestradiol, bone turnover markers and BMD were measured on days 0, 30, 90 and 180 before and after treatment. RESULTS: Application of T gel 100 mg/day resulted in serum T concentrations 1.4 and 1.9-fold higher than in the T gel 50 mg/day and the T patch groups, respectively. Proportional increases occurred in serum oestradiol. Urine N-telopeptide/creatinine ratio, a marker for bone resorption, decreased significantly (P = 0.0019) only in the T gel 100 mg/day group. Serum bone osteoblastic activity markers (osteocalcin, procollagen and skeletal alkaline phosphatase) increased significantly during the first 90 days of treatment without intergroup differences but declined to baseline thereafter. BMD increased significantly both in the hip (+1.1 +/- 0.3%) and spine (+2.2 +/- 0.5%) only in the T gel 100 mg/day group (P = 0.0001). CONCLUSIONS: Transdermal testosterone gel application for 6 months decreased bone resorption markers and increased osteoblastic activity markers for a short period, which resulted in a small but significant increase in BMD. Ongoing long-term studies should answer whether the observed increases in BMD are sustained or continue to be dependent on the dose of testosterone administered.


Assuntos
Densidade Óssea/efeitos dos fármacos , Remodelação Óssea/efeitos dos fármacos , Hipogonadismo/tratamento farmacológico , Testosterona/uso terapêutico , Administração Cutânea , Adulto , Idoso , Fosfatase Alcalina/sangue , Análise de Variância , Biomarcadores/sangue , Biomarcadores/urina , Cálcio/sangue , Colágeno/urina , Colágeno Tipo I , Creatinina/urina , Esquema de Medicação , Estradiol/sangue , Géis , Humanos , Masculino , Pessoa de Meia-Idade , Osteocalcina/sangue , Peptídeos/urina , Fósforo/sangue , Pró-Colágeno/sangue , Estudos Prospectivos , Testosterona/sangue
20.
J Clin Oncol ; 19(9): 2482-92, 2001 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-11331327

RESUMO

PURPOSE: To prospectively compare cytogenetics and reverse transcriptase-polymerase chain reaction (RT-PCR) for detection of t(8;21)(q22;q22) and inv(16)(p13q22)/t(16;16)(p13;q22), aberrations characteristic of core-binding factor (CBF) acute myeloid leukemia (AML), in 284 adults newly diagnosed with primary AML. PATIENTS AND METHODS: Cytogenetic analyses were performed at local laboratories, with results reviewed centrally. RT-PCR for AML1/ETO and CBFbeta/MYH11 was performed centrally. RESULTS: CBF AML was ultimately identified in 48 patients: 21 had t(8;21) or its variant and AML1/ETO, and 27 had inv(16)/t(16;16), CBFbeta/MYH11, or both. Initial cytogenetic and RT-PCR analyses correctly classified 95.7% and 96.1% of patients, respectively (P =.83). Initial cytogenetic results were considered to be false-negative in three AML1/ETO-positive patients with unique variants of t(8;21), and in three CBFbeta/MYH11-positive patients with, respectively, an isolated +22; del(16)(q22),+22; and a normal karyotype. The latter three patients were later confirmed to have inv(16)/t(16;16) cytogenetically. Only one of 124 patients reported initially as cytogenetically normal was ultimately RT-PCR-positive. There was no false-positive cytogenetic result. Initial RT-PCR was falsely negative in two patients with inv(16) and falsely positive for AML1/ETO in two and for CBFbeta/MYH11 in another two patients. Two patients with del(16)(q22) were found to be CBFbeta/MYH11-negative. M4Eo marrow morphology was a good predictor of the presence of inv(16)/t(16;16). CONCLUSION: Patients with t(8;21) or inv(16) can be successfully identified in prospective multi-institutional clinical trials. Both cytogenetics and RT-PCR detect most such patients, although each method has limitations. RT-PCR is required when the cytogenetic study fails; it is also required to determine whether patients with suspected variants of t(8;21), del(16)(q22), or +22 represent CBF AML. RT-PCR should not replace cytogenetics and should not be used as the only diagnostic test for detection of CBF AML because of the possibility of obtaining false-positive or false-negative results.


Assuntos
Inversão Cromossômica , Cromossomos Humanos Par 16 , Cromossomos Humanos Par 21 , Cromossomos Humanos Par 8 , Proteínas Proto-Oncogênicas , Translocação Genética , Adulto , Subunidade alfa 2 de Fator de Ligação ao Core , Proteínas de Ligação a DNA/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Proteína 1 Parceira de Translocação de RUNX1 , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição/genética
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