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1.
Sci Rep ; 9(1): 14254, 2019 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-31582770

RESUMO

Extreme weather events (e.g., cyclones, floods, droughts) are capable of changing ecosystems and altering how animals obtain resources. Understanding the behavioural responses of animals being impacted by these natural events can help initiate and ameliorate conservation or management programs. This study investigated short- and long-term space-use of the critically endangered hawksbill sea turtle (Eretmochelys imbricata), as well as five species of fishes and stingrays, in response to two of the most destructive Caribbean hurricanes in known history - Irma and Maria, which were at their peak intensity when they passed the US Virgin Islands in September of 2017. Using passive acoustic telemetry in St. Thomas, US Virgin Islands, we show a variety of short-term behavioural patterns initiated across species to reduce exposure to the strong environmental conditions, such as moving to deeper habitats within the study area. Although short-term expansion of activity space was evident for several sea turtles, long-term impacts on space-use and body condition were limited. In contrast, southern stingrays (Hypanus americanus) left the study area shortly after the hurricanes, suggesting vulnerability stemming from altered habitat, prey availability, or temperature/oxygen profiles. This study shows the strong spatial resilience of several nearshore species despite exposure to two consecutive category 5 hurricanes.


Assuntos
Tartarugas , Distribuição Animal , Animais , Região do Caribe , Tempestades Ciclônicas , Ecossistema , Telemetria , Temperatura , Tartarugas/fisiologia
2.
J Muscle Res Cell Motil ; 36(3): 263-74, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25920381

RESUMO

Myalgia and muscle weakness may appreciably contribute to the poor adherence to statin therapy. Although the pathomechanism of statin-induced myopathy is not completely understood, changes in calcium homeostasis and reduced coenzyme Q10 levels are hypothesized to play important roles. In our experiments, fluvastatin and/or coenzyme Q10 was administered chronically to normocholesterolaemic or hypercholaestherolaemic rats, and the modifications of the calcium homeostasis and the strength of their muscles were investigated. While hypercholesterolaemia did not change the frequency of sparks, fluvastatin increased it on muscles both from normocholesterolaemic and from hypercholesterolaemic rats. This effect, however, was not mediated by a chronic modification of the ryanodine receptor as shown by the unchanged ryanodine binding in the latter group. While coenzyme Q10 supplementation significantly reduced the frequency of the spontaneous calcium release events, it did not affect their amplitude and spatial spread in muscles from fluvastatin-treated rats. This indicates that coenzyme Q10 supplementation prevented the spark frequency increasing effect of fluvastatin without having a major effect on the amount of calcium released during individual sparks. In conclusion, we have found that fluvastatin, independently of the cholesterol level in the blood, consistently and specifically increased the frequency of calcium sparks in skeletal muscle cells, an effect which could be prevented by the addition of coenzyme Q10 to the diet. These results support theories favouring the role of calcium handling in the pathophysiology of statin-induced myopathy and provide a possible pathway for the protective effect of coenzyme Q10 in statin treated patients symptomatic of this condition.


Assuntos
Ácidos Graxos Monoinsaturados/farmacologia , Hipercolesterolemia/tratamento farmacológico , Hipercolesterolemia/metabolismo , Indóis/farmacologia , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Ubiquinona/análogos & derivados , Animais , Cálcio/metabolismo , Colesterol/sangue , Feminino , Fluvastatina , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Hipercolesterolemia/sangue , Doenças Musculares/sangue , Doenças Musculares/tratamento farmacológico , Doenças Musculares/metabolismo , Ratos , Ratos Endogâmicos F344 , Ubiquinona/metabolismo
3.
J Epidemiol Community Health ; 63(6): 455-60, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19228680

RESUMO

BACKGROUND: Several models have been proposed to explain the association between ethnicity and health. It was investigated whether the association between Roma ethnicity and health is fully mediated by socioeconomic status in Hungary. METHODS: Comparative health interview surveys were performed in 2003-04 on representative samples of the Hungarian population and inhabitants of Roma settlements. Logistic regression models were applied to study whether the relationship between Roma ethnicity and health is fully mediated by socioeconomic status, and whether Roma ethnicity modifies the association between socioeconomic status and health. RESULTS: The health status of people living in Roma settlements was poorer than that of the general population (odds ratio of severe functional limitation after adjustment for age and gender 1.8 (95% confidence interval 1.4 to 2.3)). The difference in self-reported health and in functionality was fully explained by the socioeconomic status. The less healthy behaviours of people living in Roma settlements was also related very strongly to their socioeconomic status, but remained significantly different from the general population when differences in the socioeconomic status were taken into account, (eg odds ratio of daily smoking 1.6 (95% confidence interval 1.3 to 2.0) after adjustment for age, gender, education, income and employment). CONCLUSION: Socioeconomic status is a strong determinant of health of people living in Roma settlements in Hungary. It fully explains their worse health status but only partially determines their less healthy behaviours. Efforts to improve the health of Roma people should include a focus on socioeconomic status, but it is important to note that cultural differences must be taken into account in developing public health interventions.


Assuntos
Nível de Saúde , Roma (Grupo Étnico)/estatística & dados numéricos , Classe Social , Adolescente , Adulto , Dieta/etnologia , Escolaridade , Feminino , Comportamentos Relacionados com a Saúde , Inquéritos Epidemiológicos , Humanos , Hungria/epidemiologia , Masculino , Pessoa de Meia-Idade , Modelos Psicológicos , Fumar/etnologia , Adulto Jovem
4.
Mar Pollut Bull ; 56(12): 1983-91, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18834601

RESUMO

Managing the effects of anthropogenic disturbance on coral reefs is highly dependant on effective strategies to assess degradation and recovery. We used five years of field data in the US Virgin Islands to investigate coral reef response to a potential gradient of stress. We found that the prevalence of old partial mortality, bleaching, and all forms of coral health impairment (a novel category) increased with nearshore anthropogenic processes, such as a five-fold higher rate of clay and silt sedimentation. Other patterns of coral health, such as recent partial mortality, other diseases, and benthic cover, did not respond to this potential gradient of stress or their response could not be resolved at the frequency or scale of monitoring. We suggest that persistent signs of disturbance are more useful to short-term, non-intensive (annual) coral reef assessments, but more intensive (semi-annual) assessments are necessary to resolve patterns of transient signs of coral health impairment.


Assuntos
Antozoários/fisiologia , Monitoramento Ambiental/métodos , Estresse Fisiológico , Poluição Química da Água , Animais , Oceano Atlântico , Ecossistema , Ilhas Virgens Americanas
5.
Child Care Health Dev ; 31(5): 615-25, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16101659

RESUMO

INTRODUCTION: Pain may signal impending or actual injury, or the achievement of optimum workload to produce a physical conditioning effect. These different functions of pain present a challenge for athletes wanting to improve their skill and conditioning level in the most efficient manner without injury. As children may be particularly vulnerable to exacerbating pain and injury owing to limited knowledge, it is important to learn more about the development of their understanding of pain concepts (e.g. pain as a signal of impending injury vs. soreness from exertion). METHODS: A structured interview and scoring criteria were developed to measure children's understanding of the functions of pain in sport and the consequences of pain and injury. Competitive gymnasts (6-13 years; n = 68; 63% girls) were interviewed and their responses were scored for indices of understanding of different types of pain. RESULTS: Age differences were found in: number of different types of pain identified; understanding of pain causality; understanding the value of pain; distinguishing pain from exertion; and use of pain descriptors. Analyses revealed that gymnasts responded differently to different types of pain and were aware of the need to stop their sport in some cases and to continue in others. Most did not describe social pressure to continue gymnastics while in pain. Gymnasts demonstrated an understanding that there was little they could do about chronic pain, yet appreciated that pain or damage could worsen with continued practice. DISCUSSION: This study was a first step in elucidating young gymnasts' understanding of sport-related pain. Further research is needed with athletes from other sports, and comparisons should be made with non-athletic children and those with pain from other sources. Within various sports, it will be important to determine the relative effects of age, sex, and number of hours spent training. Appreciation of individual differences in children's understanding of pain may contribute to prevention of injury in sport. For example, children who understand the difference between soreness from exertion and acute pain owing to injury may be able to make better decisions about pain management and continued practice.


Assuntos
Ginástica/lesões , Ginástica/psicologia , Dor/psicologia , Adolescente , Fatores Etários , Análise de Variância , Traumatismos em Atletas/prevenção & controle , Traumatismos em Atletas/psicologia , Atitude Frente a Saúde , Criança , Desenvolvimento Infantil , Linguagem Infantil , Feminino , Humanos , Entrevistas como Assunto , Masculino , Motivação , Esforço Físico/fisiologia , Fatores Sexuais , Inquéritos e Questionários
6.
Rev. biol. trop ; 53(supl.1): 155-163, maio 2005. tab, graf
Artigo em Inglês | LILACS | ID: lil-456506

RESUMO

Otolith-based reconstructions of daily larval growth increments were used to examine the effect of variation in larval growth on size and age at settlement and post-settlement growth, survival and habitat preferences of juvenile bicolor damselfish (Stegastes partitus Poey). During August 1992 and 1994, newly settled S. partitus were collected from Montastraea coral heads and Porites rubble piles in Tague Bay, St. Croix, U.S. Virgin Islands (17 degrees 45'N, 64 degres 42' W). Daily lapillar otolith increments from each fish were counted and measured with Optimas image analysis software. S. partitus pelagic larval duration was 23.7 d in 1992 (n = 70) and 24.6 d in 1994 (n = 38) and larval age at settlement averaged 13.0 mm total length both years. Analysis of daily otolith increments demonstrated that variation in larval growth rates and size and age at settlement had no detectable effect on post-settlement survivorship but that larger larvae showed a preference for Montastraea coral at settlement. Late larval and early juvenile growth rates showed a significant positive relationship indicating that growth patterns established during the planktonic stage can span metamorphosis and continue into the benthic juvenile phase. Larval growth rates during the first two weeks post-hatching also had a strong effect on age to developmental competence (ability to undergo metamorphosis) in both 1992 and 1994 with the fastest growing larvae being 8 d younger and 0.8 mm smaller at settlement than the slowest growing larvae. These differential growth rates in early stage larvae established trajectories toward larval developmental competence and may prove important in biogeographical studies of larval dispersal


Assuntos
Animais , Larva/crescimento & desenvolvimento , Membrana dos Otólitos/crescimento & desenvolvimento , Perciformes/crescimento & desenvolvimento , Fatores Etários , Tamanho Corporal/fisiologia , Ecossistema , Membrana dos Otólitos/anatomia & histologia , Densidade Demográfica , Dinâmica Populacional , Análise de Regressão , Fatores de Tempo
7.
Magn Reson Imaging ; 19(2): 167-75, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11358654

RESUMO

The objective of this study was to investigate MRI methods for monitoring focused ultrasound surgery (FUS) of breast tumors. To this end, the mammary glands of sheep were used as tissue model. The tissue was treated in vivo with numerous single sonications which covered extended target volumes by employing a scanning technique. The ultrasound focus position was controlled by online temperature mapping based on the temperature dependence of the relaxation time T(1). This approach proved to be reliable and offers thus an alternative to proton resonance frequency methods, whose application is hampered in fatty tissues. FUS-induced tissue changes were visible on T(2)- as well as on pre- and post-contrast T(1)-weighted images. According to our initial experience, noninvasive MRI-guided FUS of breast tumors is feasible.


Assuntos
Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética/instrumentação , Glândulas Mamárias Animais/cirurgia , Monitorização Intraoperatória/instrumentação , Terapia por Ultrassom/instrumentação , Tecido Adiposo/cirurgia , Animais , Temperatura Corporal/fisiologia , Feminino , Glândulas Mamárias Animais/patologia , Ovinos
8.
Pediatr Infect Dis J ; 19(8): 717-22, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10959739

RESUMO

BACKGROUND: Tinea gladiatorum is a common problem in competitive wrestling. It impacts on a wrestler's ability to compete. Several methods have been advocated to prevent these infections; however, no well-designed study of pharmacologic prophylaxis has been conducted. METHODS: In a double blind placebo-controlled trial during the 1998 to 1999 regular wrestling season, wrestlers were randomized to receive 100 mg of fluconazole once weekly or placebo once weekly. Those not involved in the study were treated as a second control group. The effects of prophylaxis were also examined by assessing treatment of clinical infections with fluconazole 200 mg weekly for 4 weeks. RESULTS: There was a significantly smaller incidence of infection in those given fluconazole (6%) than in those receiving placebo (22%) and those not involved in the prophylaxis phase (18%) (P<0.05). There was also a significant reduction in the total number of infections in the fluconazole group (P<0.05). Prophylaxis with fluconazole did not impact on the severity of disease, if contracted, when compared with the placebo prophylaxis participants who contracted tinea corporis. Of 21 wrestlers with tinea infections and positive cultures, 14 were able to have their isolates identified as Trichophyton tonsurans. CONCLUSIONS: Fluconazole is effective and safe for primary prevention of tinea gladiatorum. We must now define when and in what population prophylaxis would be warranted.


Assuntos
Antifúngicos/administração & dosagem , Fluconazol/administração & dosagem , Tinha/tratamento farmacológico , Tinha/prevenção & controle , Luta Romana , Adolescente , Método Duplo-Cego , Humanos , Incidência , Masculino , Prevenção Primária/métodos , Probabilidade , Valores de Referência , Fatores de Risco , Tinha/epidemiologia , Resultado do Tratamento
9.
J Athl Train ; 35(4): 427-30, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16558657

RESUMO

OBJECTIVE: To determine if the fungal molds (dermatophytes) responsible for causing ringworm could be isolated from a section of wrestling mat during the 1998-1999 season. DESIGN AND SETTING: A 2-part study was conducted. The first phase involved a culture evaluation of material taken from wrestling mats at 8 local high schools. The second phase was a bench laboratory study to determine if the fungus and molds could be grown from a wrestling mat in an optimal setting. SUBJECTS: We obtained material from areas of the practice mats of 8 high school wrestling teams at monthly intervals during the wrestling season. A 0.61-m (2-ft)x 0.31-m (1-ft) area of mat from 1 of the schools was used for the laboratory phase of the study. MEASUREMENTS: We cultured samples taken from each school's wrestling mats for growth of dermatophytes and used a questionnaire to determine the mat-washing habits and policies of each school. Also, wrestlers from the 8 schools were screened weekly by the designated team physician and certified athletic trainer. Any suspicious lesions were cultured for fungi. RESULTS: No dermatophytes were grown from the swab specimens taken at the 8 schools, and no dermatophytes were isolated from a section of mat evaluated in optimal laboratory conditions. CONCLUSIONS: It is unlikely that wrestling mats are a source of ringworm infections in wrestlers.

11.
J Am Soc Nephrol ; 9(12): 2223-34, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9848776

RESUMO

Angiotensin II receptor antagonists have become clinically available for the treatment of arterial hypertension. Presently, there is little information about their effects on BP, proteinuria, and renal function in patients with moderate or advanced renal failure. This study examines the effects of the angiotensin II antagonist Valsartan (80 mg/d) on proteinuria and glomerular permselectivity in patients with chronic renal failure during a 6-mo treatment, using a double-blind, randomized, placebo-controlled study (treatment group [V-group]: n = 5, age 57 +/- 7 yr, serum creatinine 365 +/- 122 micromol/L; placebo group [P-group]: n = 4, age 62 +/- 11 yr, serum creatinine 346 +/- 61 micromol/L). Study parameters included BP, 24-h proteinuria, GFR, and effective renal plasma flow (ERPF) as determined by inulin and para-aminohippurate clearance. Changes in glomerular permselectivity were assessed by measuring the fractional clearances of neutral dextrans by HPLC gel-permeation chromatography. Valsartan lowered the mean arterial pressure on average by 13 +/- 7 mmHg during the 6-mo treatment (P < 0.05). GFR and ERPF remained almost unchanged. However, after 6 mo of Valsartan treatment, proteinuria was reduced by 396 +/- 323 mg/24 h (26 +/- 18%) and albuminuria by 531 +/- 499 mg/24 h (41 +/- 21%) with regard to baseline values (P < 0.05). In the P-group, both proteinuria and albuminuria increased slightly with time (by 30 +/- 43% and 30 +/- 54%, respectively, NS). The fractional clearances of high molecular weight dextrans >66 A were significantly reduced after 6 mo of Valsartan treatment (P < 0.05), indicating a reduction of the glomerular shunt volume by 54 +/- 20% (P < 0.05) according to the model of Deen et al. (Am J Physiol 249: 347-389, 1985). The mean pore size radius of the glomerular membrane remained unchanged. This effect was independent of glomerular hemodynamic changes. Valsartan persistently lowered proteinuria in patients with chronic renal failure. Although GFR and ERPF remained nearly stable, this effect could be attributed to an improvement in glomerular permselectivity.


Assuntos
Angiotensina II/antagonistas & inibidores , Anti-Hipertensivos/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Hipertensão Renal/tratamento farmacológico , Falência Renal Crônica/tratamento farmacológico , Proteinúria/tratamento farmacológico , Circulação Renal/efeitos dos fármacos , Tetrazóis/farmacologia , Valina/análogos & derivados , Idoso , Albuminúria/tratamento farmacológico , Anti-Hipertensivos/uso terapêutico , Nitrogênio da Ureia Sanguínea , Creatinina/sangue , Dextranos/química , Método Duplo-Cego , Contagem de Eritrócitos/efeitos dos fármacos , Feminino , Taxa de Filtração Glomerular , Humanos , Hipertensão Renal/etiologia , Inulina/urina , Falência Renal Crônica/complicações , Glomérulos Renais/efeitos dos fármacos , Glomérulos Renais/fisiopatologia , Masculino , Pessoa de Meia-Idade , Peso Molecular , Tamanho da Partícula , Potássio/sangue , Estudos Prospectivos , Tetrazóis/uso terapêutico , Valina/farmacologia , Valina/uso terapêutico , Valsartana , Ácido p-Aminoipúrico/urina
15.
Brain Behav Immun ; 1(3): 251-66, 1987 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3505759

RESUMO

Three experiments were conducted to evaluate the role of drug-dosage and stimulus-specificity parameters on the tolerance of drug-induced (poly I:C) natural killer (NK) cell activity. In the first experiment a protocol which provided mice with four weekly 20 micrograms/mouse ip injections of the immunostimulatory synthetic polynucleotide (poly I:C) following exposure to either a simple odor cue or a complex cue resulted in tolerance of NK cell activity. The identical protocol with a higher drug dose (50 micrograms/mouse) did not produce tolerance. In a second experiment, the stimulus specificity of tolerance was assessed by giving two groups of mice repeated signaled drug injections. For one of these groups the final poly I:C injection of the series was signaled, while for the other group it was not. Although both groups were tolerant relative to controls not previously exposed to the drug, indirect evidence of conditioning was obtained. Specifically, it was found that tolerance among mice receiving the signal on the test was such that they were not different from undrugged controls, while uncued mice had significantly higher levels of NK cell activity. The third experiment evaluated the role of stimulus specificity within an extinction paradigm. It was found that tolerance was reversed in mice provided with repeated nonreinforced reexposure to drug-signaling cues, while mice exposed to novel cues remained tolerant. These results further support the hypothesis that associative factors contribute to the tolerance of a drug-induced immune response.


Assuntos
Condicionamento Operante , Células Matadoras Naturais/imunologia , Ativação Linfocitária , Poli I-C/farmacologia , Animais , Relação Dose-Resposta a Droga , Tolerância a Medicamentos , Extinção Psicológica , Células Matadoras Naturais/efeitos dos fármacos , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos DBA , Odorantes , Valores de Referência
16.
J Biosoc Sci ; 17(4): 451-9, 1985 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-4055834

RESUMO

PIP: Using retrospective data from Korea, multivariate log-linear analyses were used to determine if the sex of a child influences the probability of it being breastfed, or if it influences the number of months he/she was breastfed. In Korea the likelihood of a woman not breastfeeding a child is very small. The fact that a woman is without living sons increased the average odds of not breastfeeding by 1.55 times. The absence of living sons has the strongest effect of any of the predictor variables used. The highest predicted conditional odds of not breastfeeding are for women with female infants, who live in rural areas, have less than 3 children of which none are boys, and who do not use oral contraceptives. The lowest predicted conditional odds of a woman not breastfeeding are for a city dweller, with 3 or more children of which at least 1 is a boy, who uses the pill, and whose infant is a boy. Although oral contraceptive use is significant for deciding how long to breastfeed, the direction of its effect is not what was expected had it affected lactation physiologically. Apparently, social factors are operative which make pill users more likely to breast feed than non-users. 1 possible explanation for this is that Korean women are aware of the fertility-suppressing effects of lactation and are using breastfeeding as a deliberate form of birth control. The fact that the effect of pill use becomes progressively stronger the longer that women breastfeed lends further support to this explanation. The effect of sex of child is not significant in determining the duration he/she will be breastfed. This study indicates support for the contention that Korean women are aware of the contraceptive effects of lactation, and that their decisions of breastfeed are affected by their preference for sons.^ieng


Assuntos
Aleitamento Materno , Adulto , Características Culturais , Feminino , Humanos , Lactente , Recém-Nascido , Coreia (Geográfico) , Masculino , Probabilidade , Estudos Retrospectivos
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