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1.
Scand J Med Sci Sports ; 28(3): 794-806, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28801950

RESUMO

It is recognized that stretching is an effective method to chronically increase the joint range of motion. However, the effects of stretching training on the muscle-tendon structural properties remain unclear. This systematic review with meta-analysis aimed to determine whether chronic stretching alter the muscle-tendon structural properties. Published papers regarding longitudinal stretching (static, dynamic and/or PNF) intervention (either randomized or not) in humans of any age and health status, with more than 2 weeks in duration and at least 2 sessions per week, were searched in PubMed, PEDro, ScienceDirect and ResearchGate databases. Structural or mechanical variables from joint (maximal tolerated passive torque or resistance to stretch) or muscle-tendon unit (muscle architecture, stiffness, extensibility, shear modulus, volume, thickness, cross-sectional area, and slack length) were extracted from those papers. A total of 26 studies were selected, with a duration ranging from 3 to 8 weeks, and an average total time under stretching of 1165 seconds per week. Small effects were seen for maximal tolerated passive torque, but trivial effects were seen for joint resistance to stretch, muscle architecture, muscle stiffness, and tendon stiffness. A large heterogeneity was seen for most of the variables. Stretching interventions with 3- to 8-week duration do not seem to change either the muscle or the tendon properties, although it increases the extensibility and tolerance to a greater tensile force. Adaptations to chronic stretching protocols shorter than 8 weeks seem to mostly occur at a sensory level.


Assuntos
Exercícios de Alongamento Muscular , Músculo Esquelético/fisiologia , Tendões/fisiologia , Adaptação Fisiológica , Elasticidade , Humanos , Ensaios Clínicos Controlados não Aleatórios como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Amplitude de Movimento Articular , Torque
2.
Scand J Med Sci Sports ; 26(1): 41-7, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25676048

RESUMO

Ankle joint range of motion (ROM) is notably influenced by the position of the hip joint. However, this result remains unexplained. Thus, the aim of this study was to test if the ankle passive torque and gastrocnemius muscle tension are affected by the hip and the head positions. The torque and the muscle shear elastic modulus (measured by elastography to estimate muscle tension) were collected in nine participants during passive ankle dorsiflexions performed in four conditions (by combining hip flexion at 90 or 150°, and head flexed or neutral). Ankle maximum dorsiflexion angle significantly decreased by flexing the hip from 150 to 90° (P < 0.001; mean difference 17.7 ± 2.5°), but no effect of the head position was observed (P > 0.05). Maximal passive torque and shear elastic modulus were higher with the hip flexed at 90° (P < 0.001). During submaximal ROM, no effects of the head and hip positioning (P > 0.05) were found for both torque and shear elastic modulus at a given common ankle angle among conditions. Shifts in maximal ankle angle due to hip angle manipulation are not related neither to changes in passive torque nor tension of the gastrocnemius. Further studies should be addressed to better understand the functional role of peripheral nerves and fasciae in the ankle ROM limits.


Assuntos
Articulação do Tornozelo/fisiologia , Módulo de Elasticidade/fisiologia , Tono Muscular/fisiologia , Músculo Esquelético/fisiologia , Postura/fisiologia , Amplitude de Movimento Articular/fisiologia , Adulto , Eletromiografia , Ergometria/instrumentação , Ergometria/métodos , Cabeça , Articulação do Quadril , Humanos , Masculino , Dinamômetro de Força Muscular , Torque , Ultrassonografia/instrumentação , Ultrassonografia/métodos , Adulto Jovem
3.
Int J Sports Med ; 37(3): 239-44, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26701828

RESUMO

This study examined whether a high-intensity, moderate-duration bout of stretching would produce the same acute effects as a low-intensity, long-duration bout of stretching. 17 volunteers performed 2 knee-flexor stretching protocols: a high-intensity stretch (i. e., 100% of maximum tolerable passive torque) with a moderate duration (243.5 ± 69.5-s); and a low-intensity stretch (50% of tolerable passive torque) with a long duration (900-s). Passive torque at a given sub-maximal angle, peak passive torque, maximal range of motion (ROM), and muscle activity were assessed before and after each stretching protocol (at intervals of 1, 30 and 60 min). The maximal ROM and tolerable passive torque increased for all time points following the high-intensity stretching (p<0.05), but not after the low-intensity protocol (p>0.05). 1 min post-stretching, the passive torque decreased in both protocols, but to a greater extent in the low-intensity protocol. 30 min post-test, torque returned to baseline for the low-intensity protocol and had increased above the baseline for the high-intensity stretches. The following can be concluded: 1) High-intensity stretching increases the maximal ROM and peak passive torque compared to low-intensity stretching; 2) low-intensity, long-duration stretching is the best way to acutely decrease passive torque; and 3) high-intensity, moderate-duration stretching increases passive torque above the baseline 30 min after stretching.


Assuntos
Exercícios de Alongamento Muscular/métodos , Amplitude de Movimento Articular , Torque , Adulto , Humanos , Articulação do Joelho/fisiologia , Masculino , Músculo Esquelético/fisiologia , Fatores de Tempo , Adulto Jovem
4.
Scand J Med Sci Sports ; 25(3): 338-45, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24941915

RESUMO

This study aimed to determine the influence of the head, upper trunk, and foot position on the passive knee extension (PKE) torque-angle response. PKE tests were performed in 10 healthy subjects using an isokinetic dynamometer at 2°/s. Subjects lay in the supine position with their hips flexed to 90°. The knee angle, passive torque, surface electromyography (EMG) of the semitendinosus and quadriceps vastus medialis, and stretch discomfort were recorded in six body positions during PKE. The different maximal active positions of the cervical spine (neutral; flexion; extension), thoracic spine (neutral; flexion), and ankle (neutral; dorsiflexion) were passively combined for the tests. Visual analog scale scores and EMG were unaffected by body segment positioning. An effect of the ankle joint was verified on the peak torque and knee maximum angle when the ankle was in the dorsiflexion position (P < 0.05). Upper trunk positioning had an effect on the knee submaximal torque (P < 0.05), observed as an increase in the knee passive submaximal torque when the cervical and thoracic spines were flexed (P < 0.05). In conclusion, other apparently mechanical unrelated body segments influence torque-angle response since different positions of head, upper trunk, and foot induce dissimilar knee mechanical responses during passive extension.


Assuntos
Articulação do Tornozelo/fisiologia , Articulação do Joelho/fisiologia , Força Muscular/fisiologia , Postura/fisiologia , Músculo Quadríceps/fisiologia , Amplitude de Movimento Articular/fisiologia , Nervo Isquiático/fisiologia , Torque , Adulto , Eletromiografia , Humanos , Masculino , Contração Muscular , Dinamômetro de Força Muscular , Músculo Esquelético/fisiologia , Posicionamento do Paciente , Sistema Nervoso Periférico/fisiologia , Adulto Jovem
5.
Cell Biol Toxicol ; 24(1): 75-86, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17549591

RESUMO

Astrocyte and microglia cells play an important role in the central nervous system (CNS). They react to various external aggressions by becoming reactive and releasing neurotrophic and/or neurotoxic factors. Rutin is a flavonoid found in many plants and has been shown to have some biological activities, but its direct effects on cells of the CNS have not been well studied. To investigate its potential effects on CNS glial cells, we used both astrocyte primary cultures and astrocyte/microglia mixed primary cell cultures derived from newborn rat cortical brain. The cultures were treated for 24 h with rutin (50 or 100 micromol/L) or vehicle (0.5% dimethyl sulfoxide). Mitochondrial function on glial cells was not evidenced by the MTT test. However, an increased lactate dehydrogenase activity was detected in the culture medium of both culture systems when treated with 100 micromol/L rutin, suggesting loss of cell membrane integrity. Astrocytes exposed to 50 micromol/L rutin became reactive as revealed by glial fibrillary acidic protein (GFAP) overexpression and showed a star-like phenotype revealed by Rosenfeld's staining. The number of activated microglia expressing OX-42 increased in the presence of rutin. A significant increase of nitric oxide (NO) was observed only in mixed cultures exposed to 100 micromol/L rutin. Enhanced TNFalpha release was observed in astrocyte primary cultures treated with 100 micromol/L rutin and in mixed primary cultures treated with 50 and 100 micromol/L, suggesting different sensitivity of both activated cell types. These results demonstrated that rutin affects astrocytes and microglial cells in culture and has the capacity to induce NO and TNFalpha production in these cells. Hence, the impact of these effects on neurons in vitro and in vivo needs to be studied.


Assuntos
Astrócitos/citologia , Astrócitos/efeitos dos fármacos , Microglia/citologia , Microglia/efeitos dos fármacos , Óxido Nítrico/metabolismo , Rutina/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Animais , Bisbenzimidazol , Western Blotting , Morte Celular/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Meios de Cultura , Proteína Glial Fibrilar Ácida/metabolismo , Imuno-Histoquímica , Masculino , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/biossíntese
6.
Sci Total Environ ; 644: 256-273, 2018 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-29981974

RESUMO

Widespread environmental impacts of frequent drought episodes in Brazil have resulted in several drought-related diagnostics studies. However, the potential of many "opportunistic sensors", such as the Global Positioning System (GPS), has not yet been considered in hydrological hazard monitoring in Brazil. In this study, the response of the Earth's crust to Brazil's 2012-2015 drought event in different structural provinces is analyzed by comparing GPS-observed vertical crustal deformations (VCDs) with the terrestrial water storage (TWS) derived from the Gravity Recovery and Climate Experiment (GRACE). The results indicate that there is no spatial correlation between annual amplitudes of the TWS and VCDs in different structural provinces apart from the purely elastic response of the crust to TWS dynamics, at almost all the 39 GPS stations that were analyzed. However, approximately 15% of the monitoring stations show that VCD leads TWS with a phase lag of 2-4 months. Errors associated with VCD and TWS are within the accepted range for space geodetic techniques (i.e., GPS and GRACE) and despite the need for further investigation, the phase lead seems to be associated with rainfall, which impacts the TWS through the hydrographs. Overall, the GPS-based drought index (DIVCD) reflects the water depletion in many regions of Brazil, which agrees with the GRACE-based DITWS in terms of the Spearman correlation coefficient (ranging from 0.4 to 0.9) in the Amazon, Tocantins, La Plata, and São Francisco river basins. This agreement confirms the drought persistence during the study period and that DIVCD can be used to monitor hydrological droughts. In regions in which DITWS sufficiently agrees with DIVCD (48% of the sites), near real-time drought monitoring is feasible. This could be useful in the optimization of models for the forward prediction of drought events in other regions worldwide, where GPS vertical displacements strongly correlate with hydrological GRACE signals.

7.
Toxicon ; 49(5): 601-14, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17241650

RESUMO

Prosopis juliflora is used for feeding cattle and humans. Intoxication with the plant has been reported, and is characterized by neuromuscular alterations and gliosis. Total alkaloidal extract (TAE) was obtained using acid/basic-modified extraction and was fractionated. TAE and seven alkaloidal fractions, at concentrations ranging 0.03-30 microg/ml, were tested for 24h on astrocyte primary cultures derived from the cortex of newborn Wistar rats. The MTT test and the measure of LDH activity on the culture medium, revealed that TAE and fractions F29/30, F31/33, F32 and F34/35 were cytotoxic to astrocytes. The EC(50) values for the most toxic compounds, TAE, F31/33 and F32 were 2.87 2.82 and 3.01 microg/ml, respectively. Morphological changes and glial cells activation were investigated through Rosenfeld's staining, by immunocytochemistry for the protein OX-42, specific of activated microglia, by immunocytochemistry and western immunoblot for GFAP, the marker of reactive and mature astrocytes, and by the production of nitric oxide (NO). We observed that astrocytes exposed to 3 microg/ml TAE, F29/30 or F31/33 developed compact cell body with many processes overexpressing GFAP. Treatment with 30 microg/ml TAE and fractions, induced cytotoxicity characterized by a strong cell body contraction, very thin and long processes and condensed chromatin. We also observed that when compared with the control (+/-1.34%), the proportion of OX-42 positive cells was increased in cultures treated with 30 microg/ml TAE or F29/30, F31/33, F32 and F34/35, with values raging from 7.27% to 28.74%. Moreover, incubation with 3 microg/ml F32, 30 microg/ml TAE, F29/30, F31/33 or F34/35 induced accumulation of nitrite in culture medium indicating induction of NO production. Taken together these results show that TAE and fractionated alkaloids from P. juliflora act directly on glial cells, inducing activation and/or cytotoxicity, stimulating NO production, and may have an impact on neuronal damages observed on intoxicated animals.


Assuntos
Alcaloides/toxicidade , Astrócitos/efeitos dos fármacos , Óxido Nítrico/metabolismo , Prosopis/química , Alcaloides/isolamento & purificação , Análise de Variância , Animais , Animais Recém-Nascidos , Astrócitos/citologia , Astrócitos/metabolismo , Western Blotting , Antígeno CD11b/metabolismo , Fracionamento Químico , Imuno-Histoquímica , L-Lactato Desidrogenase/metabolismo , Ratos , Ratos Wistar , Sais de Tetrazólio , Tiazóis
8.
Braz J Med Biol Res ; 40(3): 309-16, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17334527

RESUMO

Essential hypertension is a disease multifactorially triggered by genetic and environmental factors. The contribution of genetic polymorphisms of the renin-angiotensin-aldosterone system and clinical risk factors to the development of resistant hypertension was evaluated in 90 hypertensive patients and in 115 normotensive controls living in Southwestern Brazil. Genotyping for insertion/deletion of angiotensin-converting enzyme, angiotensinogen M235T, angiotensin II type 1 receptor A1166C, aldosterone synthase C344T, and mineralocorticoid receptor A4582C polymorphisms was performed by PCR, with further restriction analysis when required. The influence of genetic polymorphisms on blood pressure variation was assessed by analysis of the odds ratio, while clinical risk factors were evaluated by logistic regression. Our analysis indicated that individuals who carry alleles 235-T, 1166-A, 344-T, or 4582-C had a significant risk of developing resistant hypertension (P < 0.05). Surprisingly, when we tested individuals who carried the presumed risk genotypes A1166C, C344T, and A4582C we found that these genotypes were not associated with resistant hypertension. However, a gradual increase in the risk to develop resistant hypertension was detected when the 235-MT and TT genotypes were combined with one, two or three of the supposedly more vulnerable genotypes - A1166C (AC/AA), C344T (TC/TT) and A4582C (AC/CC). Analysis of clinical parameters indicated that age, body mass index and gender contribute to blood pressure increase (P < 0.05). These results suggest that unfavorable genetic renin-angiotensin-aldosterone system patterns and clinical risk variables may contribute to increasing the risk for the development of resistant hypertension in a sample of the Brazilian population.


Assuntos
Aldosterona/genética , Hipertensão/genética , Polimorfismo Genético , Sistema Renina-Angiotensina/genética , Brasil , Estudos de Casos e Controles , Feminino , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Hipertensão/sangue , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores Sexuais
9.
Braz J Biol ; 66(4): 975-82, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17299933

RESUMO

As a contribution to the environmental history of the Tijuca National Park, we report on two pioneering restorationist initiatives and list its the mammal species now found in this urban park. The Tijuca National Park (TNP), a 3,200 ha urban park covered by secondary tropical forest, is located within Rio de Janeiro, in southeastern Brazil. The two restorationist initiatives were a pioneer tropical forest restoration project in the nineteenth century and a fauna management project in the 70' s. The mammal list presented here was based on specimens in the Museu Nacional do Rio de Janeiro and on publications. The mammal community of TNP is composed of 49 species, of which 11 are on regional red lists, and four are on the 2003 IUCN Red List of Threatened Species. Occurrence of these threatened species and the park history itself made the TNP a priority site for studying conservation, management, and monitoring. Besides maintaining fauna and flora (including threatened species) diversity, the park benefits the population of Rio de Janeiro by providing water, green areas, and recreational and touristic opportunities.


Assuntos
Conservação dos Recursos Naturais/métodos , Monitoramento Ambiental , Mamíferos/classificação , Árvores , Animais , Brasil , Humanos
10.
Braz J Biol ; 75(4 Suppl 1): S228-38, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26628243

RESUMO

We believe that in tropics we need a community approach to evaluate road impacts on wildlife, and thus, suggest mitigation measures for groups of species instead a focal-species approach. Understanding which landscape characteristics indicate road-kill events may also provide models that can be applied in other regions. We intend to evaluate if habitat or matrix is more relevant to predict road-kill events for a group of species. Our hypothesis is: more permeable matrix is the most relevant factor to explain road-kill events. To test this hypothesis, we chose vertebrates as the studied assemblage and a highway crossing in an Atlantic Forest region in southeastern Brazil as the study site. Logistic regression models were designed using presence/absence of road-kill events as dependent variables and landscape characteristics as independent variables, which were selected by Akaike's Information Criterion. We considered a set of candidate models containing four types of simple regression models: Habitat effect model; Matrix types effect models; Highway effect model; and, Reference models (intercept and buffer distance). Almost three hundred road-kills and 70 species were recorded. River proximity and herbaceous vegetation cover, both matrix effect models, were associated to most road-killed vertebrate groups. Matrix was more relevant than habitat to predict road-kill of vertebrates. The association between river proximity and road-kill indicates that rivers may be a preferential route for most species. We discuss multi-species mitigation measures and implications to movement ecology and conservation strategies.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , Veículos Automotores , Vertebrados , Animais , Brasil , Florestas , Mortalidade , Movimento
11.
Cad Saude Publica ; 7(2): 251-66, 1991.
Artigo em Português | MEDLINE | ID: mdl-15830045

RESUMO

This paper examines the practice of abortion, especially induced abortion among low income women. The discussion is based on survey data collected between 1984 and 1985 in seven slum communities (favelas) situated in the metropolitan area of Rio de Janeiro, Brazil. Despite restrictive law, induced abortion is extremely frequent. Among married women 21.4 per cent reported experience of induced abortion. Most abortions were performed by physicians, however the quality of care of these procedures can be questioned since almost all induced abortions are illegal there is no possible supervision by health authorities. The incidence of post-abortion complication is very high, especially for those performed by traditional midwifes or by the woman herself. More than 60 per cent of the women were not using contraception at the time of pregnancy. About, 21 per cent reported that they were using the pill. Such a high pill failure rate is inacceptable, and probably was related to incorrect use. This points to the need for a better access to family planning care within the health services. The consequences of the restrictive abortion laws in Brazil are also discussed. Restrictions that in practice prove to have little impact on the practice of induced abortion, appear to be very effective in brooding even more the social-economic inequalities.

12.
Braz J Biol ; 62(4B): 795-800, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12659030

RESUMO

Studies quantifying habitat structure generally use several instruments. This paper aims to propose a new and efficient device to characterize microhabitat structure of small mammals. Seven measurements were taken: plant cover, litter cover, rock cover, canopy cover, and vegetative obstruction at three heights. The device is a 0.25 m2 square wooden frame (0.50 m x 0.50 m) divided in to 100 open squares by wire mesh. Average time spent to measure each trapping station was six minutes. This new device is efficient, i.e., quick, practical, simple, and reliable. It can be used in any kind of forest. We propose this method as a standard method to describe habitat structure.


Assuntos
Ecossistema , Monitoramento Ambiental/instrumentação , Mamíferos , Plantas , Animais
13.
Braz J Biol ; 72(4): 865-71, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23295516

RESUMO

The Collared Crescentchest (Melanopareia torquata) is a small insectivore endemic to the Cerrado. We examine the habitat use of this bird in a preserved Cerrado area in southeastern Brazil. Despite its occurrence in grassland with shrubs, the species used these areas less frequently than expected. The Collared Crescentchest mainly used areas of campo cerrado, but it was not recorded in a disturbed one. The common occurrence of exotic grass (U. decumbens) and cattle grazing may have brought about factors for its occurrence. However, the preference for native grasses may indicate an adverse indirect relationship against its occurence as there is competition between native and exotic grasses in the Cerrado. The presence of the Collared Crescentchest included the highest density of tall shrubs (>1 m) and native grasses. Conservation of the species should involve preserved areas of campo cerrado with a dominance of native grasses and tall shrubs.


Assuntos
Aves/fisiologia , Ecossistema , Animais , Aves/classificação , Brasil , Monitoramento Ambiental , Densidade Demográfica , Estações do Ano
14.
Braz. j. biol ; Braz. j. biol;75(4)Nov. 2015.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468344

RESUMO

Abstract We believe that in tropics we need a community approach to evaluate road impacts on wildlife, and thus, suggest mitigation measures for groups of species instead a focal-species approach. Understanding which landscape characteristics indicate road-kill events may also provide models that can be applied in other regions. We intend to evaluate if habitat or matrix is more relevant to predict road-kill events for a group of species. Our hypothesis is: more permeable matrix is the most relevant factor to explain road-kill events. To test this hypothesis, we chose vertebrates as the studied assemblage and a highway crossing in an Atlantic Forest region in southeastern Brazil as the study site. Logistic regression models were designed using presence/absence of road-kill events as dependent variables and landscape characteristics as independent variables, which were selected by Akaikes Information Criterion. We considered a set of candidate models containing four types of simple regression models: Habitat effect model; Matrix types effect models; Highway effect model; and, Reference models (intercept and buffer distance). Almost three hundred road-kills and 70 species were recorded. River proximity and herbaceous vegetation cover, both matrix effect models, were associated to most road-killed vertebrate groups. Matrix was more relevant than habitat to predict road-kill of vertebrates. The association between river proximity and road-kill indicates that rivers may be a preferential route for most species. We discuss multi-species mitigation measures and implications to movement ecology and conservation strategies.


Resumo Nós acreditamos que nos trópicos, precisamos de uma abordagem de comunidade para avaliar os impactos das estradas sobre a vida silvestre, e então, sugerir medidas de mitigação para grupos de espécies ao invés da abordagem de espécie-foco. Compreender quais características da paisagem indicam eventos de atropelamento podem também fornecer modelos que podem ser aplicados em outras regiões. Nós pretendemos avaliar se habitat ou matriz é mais relevante para prever eventos de atropelamento para grupos de espécies. Nossa hipótese é: matriz mais permeável é o fator mais relevante para explicar os eventos de atropelamentos. Para testar essa hipótese, escolhemos vertebrados como a assembléia estudada e uma rodovia cruzando uma região de Mata Atlântica no sudeste do Brasil como área de estudo. Modelos de regressão logística foram criados usando presença/ausência de eventos de atropelamentos como variáveis dependentes e características da paisagem como variáveis independentes, os quais foram selecionados pelo Critério de Informação de Akaike. Nós consideramos um conjunto de modelos candidatos contendo quatro tipos de modelos de regressão simples: modelo de efeito de habitat; modelos de efeito de tipos de matriz; modelo de efeito da rodovia; e, modelos de referência (intercepto e distância da faixa de influência). Quase 300 atropelamentos e 70 espécies foram registradas. Proximidade do rio e cobertura da vegetação herbácea, ambos modelos de efeito da matriz, foram associadas à maioria dos grupos de vertebrados atropelados. Matriz foi mais relevante do que habitat para prever atropelamentos de vertebrados. A associação entre proximidade do rio e atropelamentos indica que rios podem ser a rota preferencial para a maioria das espécies. Nós discutimos medidas de mitigação multi-espécies e implicações para a ecologia do movimento e estratégias de conservação.

15.
Braz. j. biol ; Braz. j. biol;75(4,supl.1): 228-238, Nov. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-768227

RESUMO

Abstract We believe that in tropics we need a community approach to evaluate road impacts on wildlife, and thus, suggest mitigation measures for groups of species instead a focal-species approach. Understanding which landscape characteristics indicate road-kill events may also provide models that can be applied in other regions. We intend to evaluate if habitat or matrix is more relevant to predict road-kill events for a group of species. Our hypothesis is: more permeable matrix is the most relevant factor to explain road-kill events. To test this hypothesis, we chose vertebrates as the studied assemblage and a highway crossing in an Atlantic Forest region in southeastern Brazil as the study site. Logistic regression models were designed using presence/absence of road-kill events as dependent variables and landscape characteristics as independent variables, which were selected by Akaike’s Information Criterion. We considered a set of candidate models containing four types of simple regression models: Habitat effect model; Matrix types effect models; Highway effect model; and, Reference models (intercept and buffer distance). Almost three hundred road-kills and 70 species were recorded. River proximity and herbaceous vegetation cover, both matrix effect models, were associated to most road-killed vertebrate groups. Matrix was more relevant than habitat to predict road-kill of vertebrates. The association between river proximity and road-kill indicates that rivers may be a preferential route for most species. We discuss multi-species mitigation measures and implications to movement ecology and conservation strategies.


Resumo Nós acreditamos que nos trópicos, precisamos de uma abordagem de comunidade para avaliar os impactos das estradas sobre a vida silvestre, e então, sugerir medidas de mitigação para grupos de espécies ao invés da abordagem de espécie-foco. Compreender quais características da paisagem indicam eventos de atropelamento podem também fornecer modelos que podem ser aplicados em outras regiões. Nós pretendemos avaliar se habitat ou matriz é mais relevante para prever eventos de atropelamento para grupos de espécies. Nossa hipótese é: matriz mais permeável é o fator mais relevante para explicar os eventos de atropelamentos. Para testar essa hipótese, escolhemos vertebrados como a assembléia estudada e uma rodovia cruzando uma região de Mata Atlântica no sudeste do Brasil como área de estudo. Modelos de regressão logística foram criados usando presença/ausência de eventos de atropelamentos como variáveis dependentes e características da paisagem como variáveis independentes, os quais foram selecionados pelo Critério de Informação de Akaike. Nós consideramos um conjunto de modelos candidatos contendo quatro tipos de modelos de regressão simples: modelo de efeito de habitat; modelos de efeito de tipos de matriz; modelo de efeito da rodovia; e, modelos de referência (intercepto e distância da faixa de influência). Quase 300 atropelamentos e 70 espécies foram registradas. Proximidade do rio e cobertura da vegetação herbácea, ambos modelos de efeito da matriz, foram associadas à maioria dos grupos de vertebrados atropelados. Matriz foi mais relevante do que habitat para prever atropelamentos de vertebrados. A associação entre proximidade do rio e atropelamentos indica que rios podem ser a rota preferencial para a maioria das espécies. Nós discutimos medidas de mitigação multi-espécies e implicações para a ecologia do movimento e estratégias de conservação.


Assuntos
Animais , Conservação dos Recursos Naturais/métodos , Ecossistema , Veículos Automotores , Vertebrados , Brasil , Florestas , Mortalidade , Movimento
16.
Environ Pollut ; 157(2): 637-45, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18851890

RESUMO

The scavenging processes of chemical species have been previously studied with numerical modeling, in order to understand the gas and particulate matter intra-reservoir transferences. In this study, the atmospheric (RAMS) and scavenging (B.V.2) models were used, in order to simulate sulfate concentrations in rainwater using scavenging processes as well as the local atmospheric conditions obtained within the LBA Project in the State of Rondonia, during a dry-to-wet transition season. Two case studies were conducted. The RAMS atmospheric simulation of these events presented satisfactory results, showing the detailed microphysical processes of clouds in the Amazonian region. On the other hand, with cloud entrainments, observed values have been overestimated. Modeled sulfate rainwater concentration, using exponential decay and cloud heights of 16 km and no entrainments, presented the best results, reaching 97% of the observed value. The results, using shape parameter 5, are the best, improving the overall result.


Assuntos
Modelos Químicos , Chuva/química , Sulfatos/análise , Poluentes Químicos da Água/análise , Movimentos do Ar , Poluentes Atmosféricos/análise , Atmosfera/análise , Brasil , Monitoramento Ambiental/métodos , Estações do Ano , Dióxido de Enxofre/análise
17.
J Hum Hypertens ; 23(8): 553-5, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19339996

RESUMO

The contribution of kinins to the beneficial effects in cardiovascular risk reductions remains unclear. In this context, the present study examined whether the +9 bp/-9 bp polymorphism in bradykinin type 2 receptor gene, predicts hypertension risk in a large urban Brazilian population. Our finding indicated that the -9 bp allele may contribute to hypertension because of increased diastolic pressure.


Assuntos
Hipertensão/genética , Mutação INDEL , Polimorfismo Genético/genética , Receptor B2 da Bradicinina/genética , Adulto , Pressão Sanguínea/genética , Brasil , Estudos Transversais , Diástole/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Fatores de Risco , População Urbana
18.
Planej Agora ; : 1-6, 1991 Aug 14.
Artigo em Português | MEDLINE | ID: mdl-12344982

RESUMO

PIP: The National School of Public Health aided by WHO conducted a survey between 1984 and 1985 in 7 communities of Rio de Janeiro, Brazil, enlisting 1900 women aged 15-49 from 2019 households selected. 1783 were interviewed, yielding a response rate of 92%. 538 (30%) women were single, 7.2% of who had no sexual experience. 4.5% of the sample were widowed, divorced, or separated. Their familiarity with contraceptives was as follows: oral contraceptives, (OCs) 99.7%; female sterilization and the condom, 90%; coitus interruptus and vasectomy; 33%; the diaphragm, 27%; and natural methods; 22%. 83% of the women used OCs; less than 20% used the condom, coitus interruptus, or spermicides; and 5% had used the IUD. 8% of those 40 decided on tubal sterilization. 67% of the women in sexual unions used contraceptives vs. 35% of single women with sexual activity. Nonuse increased after age 35, while more than 50% of women 20 did not use contraceptives. Half of the sterilized women underwent the procedure before age 30 when they had 4 children. 66% of ligations were done during birth, and accompanied 63% Cesarean section. Only 28 of sterilizations were done by laparoscopy on another occasion. Misinformation about sterilization was rife, as 15% of sterilized women states that they wanted to bear a child in the future, and 11% thought that they could get pregnant. 42% of women aged 35 and over were sterilized by laparoscopy. In hospitals and clinics the average sterilized woman was 29.4 years old and had 3.5 children. Contraceptive prevalence was higher than the national average, it was comparable to the level in countries that have traditionally low fertility. The fact that OCs, the pill, and tubal ligation made up the predominant pattern of contraceptive use is the result of the inability of the health care system to provide an integrated family planning program with education about and provision of contraceptives.^ieng


Assuntos
Fatores Etários , Comunicação , Comportamento Contraceptivo , Anticoncepção , Acessibilidade aos Serviços de Saúde , Conhecimento , Estado Civil , Estudos de Amostragem , Esterilização Tubária , População Urbana , América , Brasil , Demografia , Países em Desenvolvimento , Serviços de Planejamento Familiar , América Latina , Casamento , População , Características da População , Pesquisa , América do Sul , Esterilização Reprodutiva
19.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;40(3): 309-316, Mar. 2007. tab
Artigo em Inglês | LILACS | ID: lil-441758

RESUMO

Essential hypertension is a disease multifactorially triggered by genetic and environmental factors. The contribution of genetic polymorphisms of the renin-angiotensin-aldosterone system and clinical risk factors to the development of resistant hypertension was evaluated in 90 hypertensive patients and in 115 normotensive controls living in Southwestern Brazil. Genotyping for insertion/deletion of angiotensin-converting enzyme, angiotensinogen M235T, angiotensin II type 1 receptor A1166C, aldosterone synthase C344T, and mineralocorticoid receptor A4582C polymorphisms was performed by PCR, with further restriction analysis when required. The influence of genetic polymorphisms on blood pressure variation was assessed by analysis of the odds ratio, while clinical risk factors were evaluated by logistic regression. Our analysis indicated that individuals who carry alleles 235-T, 1166-A, 344-T, or 4582-C had a significant risk of developing resistant hypertension (P < 0.05). Surprisingly, when we tested individuals who carried the presumed risk genotypes A1166C, C344T, and A4582C we found that these genotypes were not associated with resistant hypertension. However, a gradual increase in the risk to develop resistant hypertension was detected when the 235-MT and TT genotypes were combined with one, two or three of the supposedly more vulnerable genotypes - A1166C (AC/AA), C344T (TC/TT) and A4582C (AC/CC). Analysis of clinical parameters indicated that age, body mass index and gender contribute to blood pressure increase (P < 0.05). These results suggest that unfavorable genetic renin-angiotensin-aldosterone system patterns and clinical risk variables may contribute to increasing the risk for the development of resistant hypertension in a sample of the Brazilian population.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Aldosterona/genética , Hipertensão/genética , Polimorfismo Genético , Sistema Renina-Angiotensina/genética , Brasil , Estudos de Casos e Controles , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Hipertensão/sangue , Modelos Logísticos , Fatores de Risco , Fatores Sexuais
20.
Braz. j. biol ; Braz. j. biol;66(4): 975-982, Nov. 2006. tab
Artigo em Inglês | LILACS | ID: lil-448480

RESUMO

As a contribution to the environmental history of the Tijuca National Park, we report on two pioneering restorationist initiatives and list its the mammal species now found in this urban park. The Tijuca National Park (TNP), a 3,200 ha urban park covered by secondary tropical forest, is located within Rio de Janeiro, in southeastern Brazil. The two restorationist initiatives were a pioneer tropical forest restoration project in the nineteenth century and a fauna management project in the 70' s. The mammal list presented here was based on specimens in the Museu Nacional do Rio de Janeiro and on publications. The mammal community of TNP is composed of 49 species, of which 11 are on regional red lists, and four are on the 2003 IUCN Red List of Threatened Species. Occurrence of these threatened species and the park history itself made the TNP a priority site for studying conservation, management, and monitoring. Besides maintaining fauna and flora (including threatened species) diversity, the park benefits the population of Rio de Janeiro by providing water, green areas, and recreational and touristic opportunities.


Estudos sobre monitoramento, regeneração florestal e manejo de fauna devem usar a história ambiental como referência para compreender o passado da área de estudo e para monitorar os resultados desses estudos. Para criar a base da história ambiental para o Parque Nacional da Tijuca, relatamos duas iniciativas clássicas de restauração e a lista das espécies de mamíferos que ocorrem atualmente neste parque urbano, que depende dessas iniciativas. O Parque Nacional da Tijuca (PNT) é um parque urbano de 3.200 ha coberto por floresta tropical secundária e cercado pela cidade do Rio de Janeiro, no Sudeste do Brasil. No PNT, ocorreram duas iniciativas clássicas de restauração: a pioneira restauração da floresta tropical no século XIX e o projeto de manejo da fauna nos anos 70. A lista de mamíferos foi baseada em publicações e nos espécimens depositados no Museu Nacional do Rio de Janeiro. A comunidade de mamíferos do PNT é composta por 49 espécies, sendo 11 incluídas nas listas vermelhas regionais e quatro espécies na Lista Vermelha de Espécies Ameaçadas da IUCN de 2003. A ocorrência dessas espécies ameaçadas e a história do parque tornaram o Parque Nacional da Tijuca uma área de estudo prioritária para monitoramento, conservação e manejo. Além do PNT ser um parque urbano importante para a manutenção da diversidade da fauna e da flora, incluindo as espécies ameaçadas, também melhora a qualidade de vida da população da cidade do Rio de Janeiro, fornecendo áreas verdes, recreação, turismo e abastecimento de água. Concluindo, enfatizamos a grande importância da história ambiental no Parque Nacional da Tijuca para a composição atual da comunidade de mamíferos.


Assuntos
Humanos , Animais , Conservação dos Recursos Naturais/métodos , Monitoramento Ambiental , Mamíferos/classificação , Árvores , Brasil
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