Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 97
Filtrar
1.
Nat Commun ; 14(1): 6138, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37783682

RESUMO

Glacial lakes can form and grow due to glacial retreat, and rapid lake drainage can produce destructive floods. Outburst flood compilations show a temporal increase in frequency; however, recent studies highlight the role of observational bias, creating uncertainty about current and future glacial-lake hazards. Here, we focus on the Alaska region, which generated a third of previously documented outbursts globally. Using multitemporal satellite imagery, we documented 1150 drainages from 106 ice-dammed lakes between 1985 and 2020. Documented events became more frequent over time, however, accounting for increasing image availability reveals no significant increase occurred. Most lakes decreased in area and volume, suggesting a reduction in regional flood hazard. Our satellite-based approach documented 60% more events in a 35-year period than had previously been documented over 100 years. This suggests that outburst floods have historically been underreported and warrants systematic study of other regions.

2.
medRxiv ; 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36711886

RESUMO

Background: Gender inequity, a deeply-rooted driver of poor health globally, is expressed in society through gender norms, the unspoken rules that govern gender-related roles and behavior. The development of public health interventions focused on promoting equitable gender norms are gaining momentum internationally, but there remain critical gaps in the evidence about how these interventions are working to change behavioral outcomes. Methods: A four-arm cluster randomized control trial (cRCT) was conducted to evaluate the effects of the Reaching Married Adolescents in Niger (RMA) intervention on modern contraceptive use and intimate partner violence (IPV) among married adolescent girls and their husbands in Dosso, Niger (T1: 1042 dyads; 24 mos. follow-up: 737 dyads, 2016-2019). This study seeks to understand if changes in perceived inequitable gender norms among husbands are the mechanism behind effects on modern contraceptive use and IPV. We estimated natural direct and indirect effects via these gender norms using inverse odds ratio weighting. An intention-to-treat approach and a difference-in-differences estimator in a hierarchical linear probability model was used to estimate prevalence differences, along with bootstrapping to estimate confidence intervals. Results: The total effects of the RMA small group intervention (Arm 2) is estimated to be an 8% reduction in prevalence of IPV [95% CI: -0.18, 0.01]. For this arm, the natural indirect effect through gender inequitable social norms is associated with a 2% decrease (95% CI: -0.07, 0.12), accounting for 22.3% of this total effect, and the natural direct effect with a 6% decrease (95% CI: -0.20, -0.02) in IPV. Of the total effect of the RMA household visit intervention (Arm 1) on contraceptive use (20% increase), indirect effects via inequitable gender norms were associated with an 11% decrease (95% CI: -0.18, -0.01) and direct effects with a 32% increase (95% CI: 0.13, 0.44) in contraceptive use. For the combination arm, of the total effects on contraceptive use (19% increase), indirect effects were associated with a 9% decrease (95% CI: -0.20, 0.02) and direct effects with a 28% increase (95% CI: 0.12, 0.46). Conclusion: The present study contributes experimental evidence that the small group RMA intervention reduced IPV partially via reductions in perceived inequitable gender norms among husbands. Evidence also suggests that increases in perceived inequitable gender norms resulted in decreased contraceptive use among those receiving the household visit intervention component. Not only do these results open the "black box" around how the RMA small group intervention may create behavior change to help inform its future use, they provide evidence supporting behavior change theories and frameworks that postulate the importance of changing underlying social norms in order to reduce IPV and increase modern contraceptive use.

4.
Scand J Rheumatol ; 51(2): 97-101, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34169792

RESUMO

OBJECTIVE: The objective of this medical record review study is to define the association between smoking and SjÓ§gren's syndrome (SS) in a large rheumatoid arthritis (RA) cohort. METHODS: Electronic health records from a population-based cohort were screened for RA eligibility between 2005 and 2018. Inclusion criteria were age ≥ 18 years, two or more RA diagnoses, including two diagnoses by a rheumatologist, or positive rheumatoid factor or anti-cyclic citrullinated peptide (anti-CCP) antibody. The independent variable, smoking status, was defined as never, current, or past. The outcome, SS, was defined by two or more ICD-9 codes. Multivariable logistic regression was performed to determine odds ratios (ORs) of SS adjusted for age, sex, and race. RESULTS: Among 1861 patients with RA identified for cohort inclusion, 1296 had a reported smoking status. Current smokers were younger and less likely to be female than never smokers. The adjusted OR of current compared to never smokers was negatively associated with SS [OR 0.20, 95% confidence interval (CI) 0.06-0.65]. Female sex and age were associated with SS (OR 2.70, 95% CI 1.18-6.14; OR 3.75, 95% CI 1.23-11.4). CONCLUSION: We report that RA patients who currently smoke had 80% lower odds of SS. Age had a 3.7-fold association and female sex a 2.7-fold association with SS among RA patients. Our data suggest a negative correlation between current smoking and prevalent SS among RA patients. Prospective studies examining pack-year relationships or smoking cessation could further examine risk reduction and causality to follow-up our cross-sectional observational study.


Assuntos
Artrite Reumatoide , Síndrome de Sjogren , Adolescente , Artrite Reumatoide/diagnóstico , Autoanticorpos , Estudos Transversais , Feminino , Humanos , Estudos Prospectivos , Síndrome de Sjogren/complicações , Síndrome de Sjogren/diagnóstico , Síndrome de Sjogren/epidemiologia , Fumar/efeitos adversos , Fumar/epidemiologia
5.
PLoS One ; 15(5): e0231527, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32433715

RESUMO

BACKGROUND: Despite a growing body of literature on HIV service costs in sub-Saharan Africa, only a few studies have estimated the facility-level cost of prevention of Mother-to-Child Transmission (PMTCT) services, and even fewer provide insights into the variation of PMTCT costs across facilities. In this study, we present the first empirical costs estimation of the accelerated program for the prevention of mother-to-child transmission of HIV in Zimbabwe and investigate the determinants of heterogeneity of the facility-level average cost per service. To understand such variation, we explored the association between average costs per service and supply-and demand-side characteristics, and quality of services. One aspect of the supply-side we explore carefully is the scale of production-which we define as the annual number of women tested or the yearly number of HIV-positive women on prophylaxis. METHODS: We collected rich data on the costs and PMTCT services provided by 157 health facilities out of 699 catchment areas in five provinces in Zimbabwe for 2013. In each health facility, we measured total costs and the number of women covered with PMTCT services and estimated the average cost per woman tested and the average cost per woman on either ARV prophylaxis or ART. We refer to these facility-level average costs per service as unitary costs. We also collected information on potential determinants of the variation of unitary costs. On the supply-side, we gathered data on the scale of production, staff composition and on the types of antenatal and family planning services provided. On the demand side, we measured the total population at the catchment area and surveyed eligible pairs of mothers and infants about previous use of HIV testing and prenatal care, and on the HIV status of both mothers and infants. We explored the determinants of unitary cost variation using a two-stage linear regression strategy. RESULTS: The average annual total cost of the PMTCT program per facility was US$16,821 (median US$8,920). The average cost per pregnant woman tested was US$80 (median US$47), and the average cost per HIV-positive pregnant woman initiated on ARV prophylaxis or treatment was US$786 annually (median US$420). We found substantial heterogeneity of unitary costs across facilities regardless of facility type. The scale of production was a strong predictor of unitary costs variation across facilities, with a negative and statistically significant correlation between the two variables (p<0.01). CONCLUSIONS: These findings are the first empirical estimations of PMTCT costs in Zimbabwe. Unitary costs were found to be heterogeneous across health facilities, with evidence consistent with economies of scale.


Assuntos
Custos e Análise de Custo , Infecções por HIV/transmissão , Instalações de Saúde/economia , Transmissão Vertical de Doenças Infecciosas/economia , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Programas de Rastreamento/economia , Cuidado Pré-Natal/economia , Fármacos Anti-HIV/economia , Fármacos Anti-HIV/uso terapêutico , Feminino , HIV/isolamento & purificação , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/economia , Humanos , Lactente , Gravidez , Zimbábue
6.
Clin Neurol Neurosurg ; 180: 40-47, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30921564

RESUMO

Osteoporosis is a skeletal condition characterized by low bone mineral density (BMD). Common in older patients undergoing spinal fusion, it is a significant risk factor for instrumentation failure and related complications. The objective of this review is to articulate clear suggestions for screening and medical/surgical management strategies in patients with osteoporosis. A thorough review of the literature was conducted using PubMed. Varied search terms were applied to yield published manuscripts on osteoporosis and spine surgery. Biomechanical studies and studies conducted in animal models were excluded. Screening should be considered in those that present with multiple risk factors for low BMD. Dual-energy x-ray absorptiometry (DEXA) remains the gold standard, but Hounsfield Units (HU) have emerged as a powerful complement to DEXA. While both bisphosphonates and teriparatide have been investigated in the perioperative setting and have a positive impact on outcomes, teriparatide maintains an advantage in comparative studies. Surgical treatment need not be postponed. Standard surgical modifications such as using multiple points of fixation, varied fixation equipment, anterior/posterior instrumentation, and modified screw design/trajectories should all be considered. However, recent clinical studies focus on cement augmentation and expandable pedicle screws. All have been shown to improve bone-screw interface strength, but extravasation remains a risk of cement augmentation, and hydroxyapatite cement (HAC), while an emerging alternative to polymethyl methacrylate (PMMA), is not as well investigated in the setting of osteoporosis. Furthermore, research on expandable pedicle screws is limited. To conclude, optimizing spine surgery outcomes in the osteoporotic patient is possible with a thorough preoperative workup, medical management, and a tailoring of the surgical technique. This is especially important when performing complex spinal instrumentation.


Assuntos
Procedimentos Neurocirúrgicos/métodos , Osteoporose/diagnóstico por imagem , Osteoporose/cirurgia , Fraturas por Osteoporose/diagnóstico por imagem , Doenças da Coluna Vertebral/cirurgia , Absorciometria de Fóton/métodos , Densidade Óssea/efeitos dos fármacos , Densidade Óssea/fisiologia , Conservadores da Densidade Óssea/farmacologia , Conservadores da Densidade Óssea/uso terapêutico , Humanos , Procedimentos Neurocirúrgicos/efeitos adversos , Osteoporose/tratamento farmacológico , Fraturas por Osteoporose/prevenção & controle , Doenças da Coluna Vertebral/diagnóstico , Doenças da Coluna Vertebral/epidemiologia
7.
Mol Psychiatry ; 21(7): 975-82, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26347318

RESUMO

The rs1076560 polymorphism of DRD2 (encoding dopamine receptor D2) is associated with alternative splicing and cognitive functioning; however, a mechanistic relationship to schizophrenia has not been shown. Here, we demonstrate that rs1076560(T) imparts a small but reliable risk for schizophrenia in a sample of 616 affected families and five independent replication samples totaling 4017 affected and 4704 unaffected individuals (odds ratio=1.1; P=0.004). rs1076560(T) was associated with impaired verbal fluency and comprehension in schizophrenia but improved performance among healthy comparison subjects. rs1076560(T) also associated with lower D2 short isoform expression in postmortem brain. rs1076560(T) disrupted a binding site for the splicing factor ZRANB2, diminished binding affinity between DRD2 pre-mRNA and ZRANB2 and abolished the ability of ZRANB2 to modulate short:long isoform-expression ratios of DRD2 minigenes in cell culture. Collectively, this work implicates rs1076560(T) as one possible risk factor for schizophrenia in the Han Chinese population, and suggests molecular mechanisms by which it may exert such influence.


Assuntos
Receptores de Dopamina D2/genética , Esquizofrenia/genética , Adulto , Alelos , Processamento Alternativo/genética , Encéfalo/metabolismo , China , Cognição/fisiologia , Etnicidade/genética , Feminino , Predisposição Genética para Doença/genética , Genótipo , Humanos , Masculino , Polimorfismo de Nucleotídeo Único/genética , Precursores de RNA/metabolismo , Splicing de RNA , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Receptores de Dopamina D2/metabolismo , Fatores de Risco , Esquizofrenia/metabolismo
8.
Ecol Lett ; 17(4): 475-83, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24422586

RESUMO

As the ocean environment changes over time, a paucity of long-term data sets and historical comparisons limits the exploration of community dynamics over time in natural systems. Here, we used a long-term experimental data set to present evidence for a reversal of competitive dominance within a group of crustose coralline algae (CCA) from the 1980s to present time in the northeast Pacific Ocean. CCA are cosmopolitan species distributed globally, and dominant space holders in intertidal and subtidal systems. Competition experiments showed a markedly lower competitive ability of the previous competitively dominant species and a decreased response of competitive dynamics to grazer presence. Competitive networks obtained from survey data showed concordance between the 1980s and 2013, yet also revealed reductions in interaction strengths across the assemblage. We discuss the potential role of environmental change, including ocean acidification, in altered ecological dynamics in this system.


Assuntos
Ecossistema , Rodófitas/fisiologia , Mudança Climática , Oceano Pacífico , Rodófitas/crescimento & desenvolvimento , Água do Mar , Tempo
9.
Dev Neurorehabil ; 16(6): 398-409, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23617243

RESUMO

OBJECTIVE: This case series examines the feasibility, specificity, and preliminary effectiveness of NeuroGame Therapy (NGT) for improving wrist control in four children with cerebral palsy (CP). NGT uses surface electromyographic (sEMG) signals routed through motivating computer games to improve motor control. METHODS: Primary outcomes of NGT included feasibility (hours of play) and specificity (changes in sEMG activity during game play). Secondary outcomes included changes in co-contraction, range of motion, segmental alignment, and spontaneous upper extremity function following intervention. RESULTS: Participants completed a mean of 8.8 hours of NGT over 5-6 weeks. Participants demonstrated dramatic improvement of the sEMG activity during game play. Several participants also showed improvements in range of motion, co-contraction, and spontaneous upper extremity function following NGT. CONCLUSION: This case series provides evidence for the feasibility, specificity, and effectiveness of NGT. Future studies will pair NGT with functional practice to improve transfer of learning to daily activities.


Assuntos
Paralisia Cerebral/reabilitação , Terapia por Exercício/métodos , Amplitude de Movimento Articular/fisiologia , Punho/fisiopatologia , Adolescente , Paralisia Cerebral/fisiopatologia , Criança , Eletromiografia , Estudos de Viabilidade , Feminino , Humanos , Masculino , Projetos de Pesquisa , Resultado do Tratamento
10.
J Obstet Gynaecol ; 31(5): 390-2, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21627419

RESUMO

The aim of the study was to perform a retrospective review of records to test a possible significant association between sudden, modest weight loss (≤2 lb) between the last two prenatal appointments in the late 3rd trimester and onset of labour. Hospital and clinic records were searched for women who delivered a term baby after the onset of natural labour between 2006 and 2008, in Tulsa, OK. High-risk pregnancies were excluded. Patients were categorised by whether they lost or gained weight between their last two prenatal appointments. The groups' average times to onset of spontaneous labour were compared. A total of 149 records were obtained. Mothers who lost weight had an average onset of spontaneous labour in 2.30 days; their counterparts' average was 2.34 days. Student's t-test and Wilcoxon test p values were 0.95 and 0.61, respectively. A Kolmogorov-Smirnov test p value was 0.2139. A one-half standard deviation difference in time to delivery, approximately 2.5 days, was detectable with 0.95 probability. It was concluded that these data may be the first time this question has been investigated and provide evidence that sudden, modest weight loss at the end of pregnancy is not associated with shorter time to onset of natural labour.


Assuntos
Início do Trabalho de Parto/fisiologia , Nascimento a Termo/fisiologia , Redução de Peso , Adolescente , Adulto , Feminino , Humanos , Projetos Piloto , Gravidez , Estudos Retrospectivos , Adulto Jovem
11.
Br J Cancer ; 99(9): 1387-94, 2008 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-18971935

RESUMO

The aim of this open-label phase 1b study was to assess the safety and pharmacokinetics of motesanib in combination with gemcitabine in patients with advanced solid tumours. Eligible patients with histologically or cytologically documented solid tumours or lymphoma were enroled in three sequential, dose-escalating cohorts to receive motesanib 50 mg once daily (QD), 75 mg two times daily (BID), or 125 mg QD in combination with gemcitabine (1000 mg m(-2)). The primary end point was the incidence of dose-limiting toxicities (DLTs). Twenty-six patients were enroled and received motesanib and gemcitabine. No DLTs occurred. The 75 mg BID cohort was discontinued early; therefore, 125 mg QD was the maximum target dose. Sixteen patients (62%) experienced motesanib-related adverse events, most commonly lethargy (n=6), diarrhoea (n=4), fatigue (n=3), headache (n=3), and nausea (n=3). The pharmacokinetics of motesanib and of gemcitabine were not markedly affected after combination therapy. The objective response rate was 4% (1 of 26), and 27% (7 of 26) of patients achieved stable disease. In conclusion, treatment with motesanib plus gemcitabine was well tolerated, with adverse event and pharmacokinetic profiles similar to that observed in monotherapy studies.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Desoxicitidina/análogos & derivados , Indóis/administração & dosagem , Neoplasias/tratamento farmacológico , Niacinamida/análogos & derivados , Adulto , Idoso , Desoxicitidina/administração & dosagem , Desoxicitidina/farmacocinética , Esquema de Medicação , Feminino , Humanos , Indóis/efeitos adversos , Indóis/farmacocinética , Masculino , Pessoa de Meia-Idade , Niacinamida/administração & dosagem , Niacinamida/efeitos adversos , Niacinamida/farmacocinética , Oligonucleotídeos , Gencitabina
12.
J Food Sci ; 72(3): M94-7, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17995807

RESUMO

The need to control pathogenic microorganisms in the intestinal tract of dogs is a growing concern. There is interest in using probiotics such as species of Lactobacillus to help control canine intestinal infections. For successful use as a probiotic, the bacterial species should be of canine intestinal origin since these species exhibit host specificity. Serial dilutions of freshly voided dog feces were plated on Lactobacillus selection (LBS) agar to isolate the cultures. Isolates were identified based on Gram stain, catalase test, and fermentation patterns using API 50 CH kits. All potential isolates were compared for bile resistance based on relative ability to grow in broth containing 0.3% Oxgall, the ability to inhibit Salmonella Typhimurium in associative broth cultures, and the production of reuterin. Of the lactobacilli isolated, Lactobacillus reuteri was the dominant species. However, some cultures of L. acidophilus also were isolated. We found variations among the isolates of L. reuteri and L. acidophilus with respect to bile tolerance. In general, isolates of L. reuteri appeared to be more bile resistant than were isolates of L. acidophilus. There were also variations in the ability to inhibit growth of S. Typhimurium. Some isolates of L. reuteri produced reuterin while others did not.


Assuntos
Doenças do Cão/microbiologia , Fezes/microbiologia , Lactobacillus/fisiologia , Probióticos , Salmonella typhimurium/crescimento & desenvolvimento , Aldeídos/metabolismo , Animais , Antibiose , Doenças do Cão/prevenção & controle , Cães , Gliceraldeído/análogos & derivados , Gliceraldeído/metabolismo , Lactobacillus/isolamento & purificação , Lactobacillus acidophilus/isolamento & purificação , Lactobacillus acidophilus/fisiologia , Limosilactobacillus reuteri/isolamento & purificação , Limosilactobacillus reuteri/fisiologia , Propano/metabolismo , Especificidade da Espécie
13.
Scand J Clin Lab Invest ; 66(4): 351-5, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16777763

RESUMO

The effects of a lower-extremity progressive resistance-training program (PRT) on risk factors for coronary artery disease (CAD) were determined in patients with multiple sclerosis (MS). Twelve ambulatory women with MS (47.3+/-4.7 years; Expanded Disability Status Score (EDSS), 4.00+/-1.37) completed twice weekly lower-body PRT for 8 weeks. Knee extensor and ankle flexor strength improved significantly (p<0.05) after training, and self-reported fatigue decreased (p<0.05). Serum triglyceride concentrations decreased (p<0.05) but body-weight and fatness, blood pressure, and serum glucose, total cholesterol and high-density lipoprotein cholesterol were unchanged. However, the number of CAD risk factors that reached the clinical threshold for each subject declined after PRT, suggesting that resistance training can promote CAD risk reduction in ambulatory female MS subjects.


Assuntos
Doença da Artéria Coronariana/prevenção & controle , Exercício Físico/fisiologia , Esclerose Múltipla/complicações , Atividades Cotidianas , Feminino , Humanos , Pessoa de Meia-Idade , Fatores de Risco , Estatísticas não Paramétricas
14.
Qual Life Res ; 14(3): 837-47, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16022076

RESUMO

PROBLEM AND PURPOSE: The Lung Cancer Symptom Scale (LCSS), a site-specific health-related quality of life measure for patients with lung cancer, was originally developed using a Visual Analogue Scale (VAS) format. However, the VAS format is not readily compatible with data management and software programs using scanning. The primary aim of this study was to evaluate the convergence of ratings obtained with a Numerical Rating Scale (NRS), with an 11-pt response category format, to those obtained with a VAS format. The intent was to determine the degree of agreement between two formats to generalize the existing psychometric properties for the original measure to the new presentation. DESIGN/SETTING: This methodological study evaluated the feasibility, reliability, and validity of a NRS format for the LCSS. The study was conducted at two cancer centers in New York City. PATIENTS/PROCEDURES: Sixty-eight patients with non-small cell lung cancer (NSCLC) completed both versions of the LCSS along with demographic and feasibility questions on a single occasion. The VAS form was administered first, followed by the NRS form to prevent bias. The intraclass correlation coefficient (ICC), Lin's concordance correlation coefficient (CCC), and Bland-Altman plots were used to evaluate agreement and to characterize bias. RESULTS: Cronbach's alpha for the NRS format total score was 0.89 for the 68 patients with NSCLC. Agreement was excellent, with both the ICC and CCC > or = 0.90 for the two summary scores (total score and average symptom burden index) for the LCSS. Only five of the nine individual items showed this level of strict agreement. An agreement criterion of > or = 0.80 (representing excellent) was observed for seven of the nine individual items (all but appetite loss and hemoptysis). Mean differences tended to be slightly lower for the VAS format compared to the NRS format (more so for the appetite and hemoptysis items), with evidence of scale shift for the same two items. The summary measures showed good concordance as measured by the ICC and CCC, but did display mean differences (VAS - NRS) of -2.7 and -3.1, respectively. CONCLUSIONS: Overall, the NRS format for the LCSS suitable for scanning has good feasibility, reliability (internal consistency), and convergent validity. The complete set of concordance evaluation measures supports the reproducibility of VAS scores by NRS scores, particularly for the two summary scores.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/classificação , Neoplasias Pulmonares/classificação , Qualidade de Vida , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/fisiopatologia , Estudos de Viabilidade , Feminino , Humanos , Neoplasias Pulmonares/fisiopatologia , Masculino , Pessoa de Meia-Idade , Medição da Dor , Reprodutibilidade dos Testes , Índice de Gravidade de Doença
15.
J Sports Med Phys Fitness ; 45(4): 501-6, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16446681

RESUMO

AIM: Extensive research has been undertaken in the area of exercise and hydration. Most work has focused on prehydration. Less is known about different fluid intake patterns during exercise and its effect in thermoregulatory variables in hot environments. This study attempted to determine if ingesting fluid either in a single bolus or intermittently during exercise had different results in thermoregulatory parameters and thirst in a hot environment. METHODS: Six moderately trained men and women (n=6, 5 male, 1 female; mean+/-SD: age 28.5+/-2.5 y; weight 74.4+/-3.3 kg, VO2max 45.9+/-3.7 ml.kg.min-1) completed 2 exercise sessions in a randomized, counterbalanced order. Treatment 1 (bolus) consisted of 60 minutes of bicycling at 50% of VO2max in a climatic chamber (dry bulb temperature, 35 degrees C, 45% relative humidity). Subjects consumed 1 000 ml of plain cool (22 degrees C) water immediately before exercise. During treatment 2 (intermittent) the same environmental conditions were present, but subjects consumed 250 ml of water immediately before exercise. During the bicycle ride, subjects consumed 250 ml of cool water at minutes 15, 30, and 45 of exercise for a total trial volume of 1,000 ml. Tympanic ear temperatures, heart rates, rating of perceived exertion (RPE), and thirst scale data were collected immediately before exercise and at minutes 10, 20, 30, 40, 50, and 60 of exercise. RESULTS: No statistical differences were noted in temperature between treatments (P>0.05). Lower heart rates and thirst scores were noted for the bolus treatment at various time points (P<0.05). Little differences were noted between treatments for RPE during exercise. CONCLUSIONS: These results suggest that consumption of water in a single bolus is more beneficial for some aspects of thermoregulatory control and delaying thirst during exercise in the heat. Additional mechanistic studies with larger sample sizes are warranted.


Assuntos
Ciclismo/fisiologia , Regulação da Temperatura Corporal/fisiologia , Ingestão de Líquidos/fisiologia , Exercício Físico/fisiologia , Temperatura Alta/efeitos adversos , Consumo de Oxigênio/fisiologia , Esforço Físico/fisiologia , Adulto , Desidratação/prevenção & controle , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Sede/fisiologia , Fatores de Tempo
16.
J Speech Lang Hear Res ; 48(6): 1280-93, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16478371

RESUMO

The purpose of this investigation was to determine the utility of clinical swallowing examination (CSE) measures for detecting aspiration as defined by videofluoroscopic swallowing examination (VFSE). This study, involving 165 participants, is a follow-up to a previously published investigation of 60 participants. Findings are compared with that investigation as well as with other research on CSEs. The results suggest that clinicians can make an accurate judgment of the occurrence of aspiration in most post-stroke patients. However, ruling out aspiration when it is absent appears more problematic. More work needs to be done if data collected from non-instrumented examinations are to be strongly predictive of the presence and absence of aspiration on VFSE. At present, there are no data to suggest that CSEs can be used to quantify aspiration or make adequate recommendations regarding patient care.


Assuntos
Transtornos de Deglutição/diagnóstico , Fluoroscopia/métodos , Aspiração Respiratória/diagnóstico , Acidente Vascular Cerebral/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Transtornos de Deglutição/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Aspiração Respiratória/etiologia , Acidente Vascular Cerebral/fisiopatologia , Gravação em Vídeo
17.
Mult Scler ; 10(6): 668-74, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15584492

RESUMO

The purpose of this study was to evaluate the effect of an eight-week progressive resistance training programme on lower extremity strength, ambulatory function, fatigue and self-reported disability in multiple sclerosis (MS) patients (mean disability score 3.7 +/- 0.8). Eight MS subjects volunteered for twice weekly training sessions. During the first two weeks, subjects completed one set of 8-10 reps at 50% of maximal voluntary contraction (MVC) of knee flexion, knee extension and plantarflexion exercises. In subsequent sessions, the subjects completed one set of 10-15 repetitions at 70% of MVC. The resistance was increased by 2-5% when subjects completed 15 repetitions in consecutive sessions. Isometric strength of the quadriceps, hamstring, plantarflexor and dorsiflexor muscle groups was assessed before and after the training programme using an isokinetic dynamometer. Magnetic resonance images of the thigh were acquired before and after the exercise programme as were walking speed (25-ft), number of steps in 3 min, and self-reported fatigue and disability. Knee extension (7.4%), plantarflexion (52%) and stepping performance (8.7%) increased significantly (P < 0.05). Self-reported fatigue decreased (P < 0.05) and disability tended to decrease (P = 0.07) following the training programme. MS patients are capable of making positive adaptations to resistance training that are associated with improved ambulation and decreased fatigue.


Assuntos
Terapia por Exercício , Esclerose Múltipla/fisiopatologia , Esclerose Múltipla/terapia , Aptidão Física , Adulto , Composição Corporal , Avaliação da Deficiência , Fadiga , Feminino , Humanos , Perna (Membro) , Masculino , Pessoa de Meia-Idade , Contração Muscular/fisiologia , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/fisiologia , Avaliação Nutricional
18.
J Clin Endocrinol Metab ; 86(8): 3724-8, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11502802

RESUMO

Mutations of glutamate dehydrogenase cause the hyperinsulinism/hyperammonemia syndrome by desensitizing glutamate dehydrogenase to allosteric inhibition by GTP. Normal allosteric activation of glutamate dehydrogenase by leucine is thus uninhibited, leading us to propose that children with hyperinsulinism/hyperammonemia syndrome will have exaggerated acute insulin responses to leucine in the postabsorptive state. As hyperglycemia increases beta-cell GTP, we also postulated that high glucose concentrations would extinguish abnormal responsiveness to leucine in hyperinsulinism/hyperammonemia syndrome patients. After an overnight fast, seven hyperinsulinism/hyperammonemia syndrome patients (aged 9 months to 29 yr) had acute insulin responses to leucine performed using an iv bolus of L-leucine (15 mg/kg) administered over 1 min and plasma insulin measurements obtained at -10, -5, 0, 1, 3, and 5 min. The acute insulin response to leucine was defined as the mean increase in insulin from baseline at 1 and 3 min after an iv leucine bolus. The hyperinsulinism/hyperammonemia syndrome group had excessively increased insulin responses to leucine (mean +/- SEM, 73 +/- 21 microIU/ml) compared with the control children and adults (n = 17) who had no response to leucine (1.9 +/- 2.7 microU/ml; P < 0.05). Four hyperinsulinism/hyperammonemia syndrome patients then had acute insulin responses to leucine repeated at hyperglycemia (blood glucose, 150-180 mg/dl). High blood glucose suppressed their abnormal baseline acute insulin responses to leucine of 180, 98, 47, and 28 microU/ml to 73, 0, 6, and 19 microU/ml, respectively. This suppression suggests that protein-induced hypoglycemia in hyperinsulinism/hyperammonemia syndrome patients may be prevented by carbohydrate loading before protein consumption.


Assuntos
Glutamato Desidrogenase/genética , Hiperamonemia/fisiopatologia , Hiperinsulinismo/fisiopatologia , Insulina/metabolismo , Leucina , Mutação Puntual , Adolescente , Adulto , Substituição de Aminoácidos , Amônia/sangue , Glicemia/metabolismo , Criança , Pré-Escolar , Diazóxido , Feminino , Glutamato Desidrogenase/química , Humanos , Hiperamonemia/sangue , Hiperamonemia/genética , Hiperinsulinismo/sangue , Hiperinsulinismo/genética , Lactente , Insulina/sangue , Secreção de Insulina , Masculino , Síndrome
19.
J Pers Soc Psychol ; 80(5): 782-96, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11374749

RESUMO

Group status and status legitimacy were tested as moderators of devaluing in response to threatening intergroup comparisons. In 3 experiments, participants received feedback comparing their in-group (based on school or gender) to a higher or lower status out-group. When the legitimacy of group status differences was assumed (Studies 1 and 2) or manipulated (Study 3), participants devalued the domain when their in-group compared unfavorably with a lower status out-group but did not devalue the domain when their in-group compared unfavorably with a higher status out-group. In Study 3, this status value asymmetry was eliminated when status differences were delegitimized. Mediational analyses suggested that the status value asymmetry was explained by the perceived utility of the domain for gaining status-relevant rewards.


Assuntos
Distância Psicológica , Predomínio Social , Identificação Social , Valores Sociais , Adulto , Processos Grupais , Humanos , Masculino
20.
Bioelectromagnetics ; 22(3): 170-7, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11255212

RESUMO

This study was designed to assess the effect of exposure to long-term extremely low-frequency electric and magnetic fields (ELF-EMF) from a 500 kV transmission line on IL-1 and IL-2 activity in sheep. The primary hypothesis was that the reduction in IL-1 activity observed in our two previous short-term studies (10 months) was due to EMF exposure from this transmission line. To repeat and expand these studies and to characterize the components of EMF responsible for the previously observed reduction in IL-1 activity, the current experiment examined not only the effect of exposure to electric and magnetic fields, but also the magnetic field component alone. In the current study, IL-2 was examined to characterize the effects of EMF exposure on an indicator of T cell responses. 45 Suffolk ewe lambs were randomized into three groups of 15 animals each. One group of animals was placed in the EMF pen, located directly beneath the transmission line. A second group was placed in the shielded MF (magnetic field only) pen, also directly beneath the transmission line. The third group of animals was placed in the control pen located several hundred meters away from the transmission line. During the 27 month exposure period, blood samples were taken from all animals monthly. When the data were analyzed collectively over time, no significant differences between the groups were found for IL-1 or IL-2 activity. In previous studies ewe lambs of 8-10 weeks of age were used as the study animals and significant differences in IL-1 activity were observed after exposure of these animals to EMF at mean magnetic fields of 3.5-3.8 microT (35-38 mG) and mean electric fields of 5.2-5.8 kV/m. At the start of the current study EMF levels were reduced as compared to previous studies. One interpretation of the current data is that magnetic field strength and age of the animals may be important variables in determining whether EMF exposure will affect IL-1 activity.


Assuntos
Eletricidade , Campos Eletromagnéticos , Interleucina-1/sangue , Interleucina-2/sangue , Linfócitos/efeitos da radiação , Ovinos/imunologia , Análise de Variância , Animais , Exposição Ambiental , Feminino , Abrigo para Animais , Lipopolissacarídeos/farmacologia , Ativação Linfocitária , Linfócitos/efeitos dos fármacos , Linfócitos/imunologia , Fatores de Tempo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...