Variações fisiológicas, influência da idade e sexo no perfil bioquímico sanguíneo de aves da linhagem pesada de frango de corte na fase de recria / Physiological variations and influence of age and gender on poultry of heavy lineage of chicken´s biochemical profile during the rearing stage

Este estudo teve o objetivo de comparar o perfil bioquímico sérico de machos e fêmeas da linhagem pesada de frango de corte, nas idades de quatro, 12 e 20 semanas, em uma unidade de produção industrial, no município de Uberlândia-MG. Após a pesagem das aves, foram coletadas amostras de sangue de 15 aves de cada sexo de cada faixa etária. Os soros obtidos foram avaliados em analisador automático para os seguintes parâmetros bioquímicos: proteína total, albumina, globulinas, ácido úrico, colesterol, triglicérides, gamaglutamiltransferase, aspartato aminotransferase, alanina aminotransferase, creatina quinase, fosfatase alcalina, cálcio e fósforo. Imediatamente após a coleta de cada amostra, avaliou-se a glicemia no sangue total, utilizando-se um glicosímetro. As alterações fisiológicas e metabólicas que as aves apresentaram na fase de recria refletiram na variação dos níveis bioquímicos séricos na maioria dos constituintes avaliados, os quais exibiram diferenças significativas (P<0,05), comparando-se sexo e idade.(AU)

This study aimed to compare the levels of glucose in the blood and serum´s metabolites enzymes and minerals of poultry of heavy lineage of chicken at the age of four, twelve and twenty weeks in an industrial production unit in the city of Uberlândia-MG. After weighing the birds, blood samples were collected from 15 birds of each gender in the three ages. The serum obtained was evaluated in an automatic biochemical analyzer for the following parameters: total protein, albumin, globulin, uric acid, cholesterol, triglycerides, alkaline phosphatase, gamma-glutamyl transferase, aspartate aminotransferase, alanine aminotransferase, creatine kinase, calcium and phosphorus. Immediately after the collection of each sample, we evaluated glucose levels by means of a glycosimeter. The physiological and metabolic changes that birds present in the rearing age reflected in the variation of serum biochemical levels in most constituents evaluated, showing significant differences (P< 0.05) comparing age and gender.(AU)

Bothrops alternatus Snake Venom Induces Cytokine Expression and Oxidative Stress on Renal Function.

BACKGROUND: Envenomation caused by Bothrops alternatus is common in Southern Brazil. Acute Kidney Injury occurs after Bothrops snakebite and more information is necessaryrequired to understand its mechanism. OBJECTIVE: The objective was to evaluate the effect of Bothrops alternatus venom (BaV) on renal cells and rat isolated kidney function. METHODS: Wistar rats (n = 6, weighing 260-320 g) were perfused with a Krebs-Henseleit solution containing 6 g 100 mL-1 of bovine serum albumin. After 30 minutes, the kidneys were perfused with BaV to a final concentration of 1 and 3 µgmL-1; and subsequently were evaluated for Perfusion Pressure (PP), Renal Vascular Resistance (RVR), Urinary Flow (UF), Glomerular Filtration Rate (GFR), and percentage of electrolyte tubular transport. Renal histological analysis, cytokine release, oxidative stress and cytotoxicity in renal proximal tubular cells were assessed. RESULTS: BaV reduced PP, RVR, GFR, UF, total and proximal sodium transport (%TNa+), and chloride (%TCl-) in the isolated kidney perfusion model. Histological analysis of perfused kidneys disclosed the presence of proteinaceous material in the glomeruli and renal tubules, vacuolar tubular epithelial cell degeneration, Bowman's capsule degeneration, swelling of glomerular epithelial cells, glomerular atrophy and degeneration, and the presence of intratubular protein. Cytokine release (TNF-α, IL-1ß, IL-10) and oxidative stress were increased in the kidneys. The viability of LLC-MK2 cells (IC50: 221.3 µg/mL) was decreased by BaV and necrosis was involved in cell death. CONCLUSION: These findings indicate that BaV modifies functional parameters in an isolated perfused kidney model and has cytotoxic effects on renal lineage cells.

The association between extended spectrum beta-lactamase (ESBL) and ampicillin C (AmpC) beta-lactamase genes with multidrug resistance in Escherichia coli isolates recovered from turkeys in Brazil.

1. The aim of this study was to analyse the association between Escherichia coli isolates recovered from turkeys and the expression of beta-lactamase genes, such as extended spectrum beta-lactamase (ESBL) and ampicillin class C (AmpC). The phenotype of the resistance profile was examined using the association between amoxicillin and ceftiofur resistance. 2. Results showed that 84% from the turkey isolates harboured 4 or 5 genes associated with the CoIV plasmid. In an antibiogram test, 82% of the isolates were multidrug-resistant, the highest levels of resistance being against erythromycin (99%) and amoxicillin (76.1%). ESBL-positive groups were 31% positive for the ctx-m-2 gene, 6.8% were positive for ctx-m-8 and 70% harboured the tem wild gene. 3. All positive isolates from the AmpC beta-lactamase-positive group harboured the cmy-2 gene. The presence of the cmy-2 gene was associated with both the CTX-group genes and resistance to ceftiofur. 4. There was a high prevalence of avian pathogenic E. coli in suspected cases of colibacillosis in turkeys and a high antimicrobial resistance index. The results highlighted the risk of ceftiofur resistance and the presence of both ESBL and AmpC beta-lactamase E. coli in the turkey production chain.

Feed can be a source of Campylobacter jejuni infection in broilers.

1. The aim was to determine the importance of a contaminated diet as a possible cause of Campylobacter jejuni infection in broilers. 2. This study evaluated the viability of C. jejuni in both starter and finisher diets and the interference from other mesophilic bacteria in this viability. 3. Starter and finisher samples of broiler diet were deliberately contaminated with 3 or 5 log CFU·g-1 of C. jejuni (NCTC 11351) and then maintained at two different storage temperatures (25°C or 37°C) for 3 or 5 d. 4. C. jejuni survived during this period and, when inoculated at 103 CFU·g-1, multiplied with greater proliferation at a storage temperature of 37°C. There was no relationship between the amount of mesophilic bacteria and C. jejuni viability. 5. This study highlights the importance of the diet in the epidemiology of C. jejuni in broilers.

Distensibility index of the inferior vena cava in experimental acute respiratory distress syndrome.

We determined the accuracy of distensibility index of inferior vena cava (dIVC) for evaluation of fluid responsiveness in rats with acute respiratory distress syndrome (ARDS) and validated this index for use in rat models. In protocol 1, E. coli lipopolysaccharide was administered in Wistar rats (n=7). After 24h, animals were mechanically ventilated, and stroke volume (SV) and dIVC quantified after blood drainage and subsequent volume expansion (albumin 20%). A receiver operating characteristic (ROC) curve was plotted to determine the optimal dIVC cutoff. In protocol 2, rats (n=10) were divided into fluid-responders (SV increase >5%) and nonresponders (SV increase <5%). The dIVC cutoff obtained from protocol 1 was 25%. Fluid responders had a 2.5 relative risk of low dIVC (<25%). The sensitivity, specificity, positive predictive, and negative predictive values for dIVC were 74%, 62%, 59%, and 76%, respectively. In conclusion, a dIVC threshold <25% was associated with positive response after volume expansion and could be used to titrate fluids in endotoxin-induced ARDS.

The role of submerged trees in the early development of fishes in a Neotropical reservoir.

It was hypothesized that the structural heterogeneity provided by submerged trees positively favours the spatial distribution of fish abundance at early stages of development in an area under the influence of a Neotropical reservoir in the Paraná River basin. The distribution at early stages of development of the most abundant species was evaluated. To remove any possible confounding effect related to local environmental variables, changes in these were also evaluated. Sampling was carried out at sites with and without submerged trees. Among all individuals sampled, 96·1% were classified as larvae and 3·9% as juveniles. The area without submerged trees showed higher total abundance, but there were spatial differences in the distribution of early stage fishes. From the moment the larvae are able to swim actively, they search for sites with a complex structure. The results show that reaches with submerged trees play an important role in the early development of fishes in reservoirs, and, hence, the preservation of those trees is essential to maintain biodiversity in reservoirs.

Comparison of different degrees of variability in tidal volume to prevent deterioration of respiratory system elastance in experimental acute lung inflammation.

BACKGROUND: Variable ventilation improves respiratory function, but it is not known whether the amount of variability in tidal volume (VT) can be reduced in recruited lungs without a deterioration of respiratory system elastance. METHODS: Acute lung inflammation was induced by intratracheal instillation of lipopolysaccharide in 35 Wistar rats. Twenty-eight animals were anaesthetized and ventilated in volume-controlled mode. Lungs were recruited by random variation of VT (mean 6 ml kg(-1), coefficient of variation 30%, normal distribution) for 30 min. Animals were randomly assigned to different amounts of VT variability (n=7 for 90 min per group): 30, 15, 7.5, or 0%. Lung function, diffuse alveolar damage, and gene expression of biological markers associated with cell mechanical stress, inflammation, and fibrogenesis were assessed. Seven animals were not ventilated and served as controls for post-mortem analyses. RESULTS: A VT variability of 30%, but not 15, 7.5, or 0%, prevented deterioration of respiratory system elastance [Mean (SD) -7.5 (8.7%), P<0.05; 21.1 (9.6%), P<0.05; 43.3 (25.9), P<0.05; and 41.2 (16.4), P<0.05, respectively]. Diffuse alveolar damage was lower with a VT variability of 30% than with 0% and without ventilation, because of reduced oedema and haemorrhage. A VT variability of 30, 15, or 7.5% reduced the gene expression of amphiregulin, cytokine-induced neutrophil chemoattractant-1, and tumour necrosis factor α compared with a VT variability of 0%. CONCLUSIONS: In this model of acute lung inflammation, a VT variability of 30%, compared with 15 and 7.5%, was necessary to avoid deterioration of respiratory system elastance and was not associated with lung histological damage.

Effects of acute hypercapnia with and without acidosis on lung inflammation and apoptosis in experimental acute lung injury.

We investigated the effects of acute hypercapnic acidosis and buffered hypercapnia on lung inflammation and apoptosis in experimental acute lung injury (ALI). Twenty-four hours after paraquat injection, 28 Wistar rats were randomized into four groups (n=7/group): (1) normocapnia (NC, PaCO2=35-45 mmHg), ventilated with 0.03%CO2+21%O2+balancedN2; (2) hypercapnic acidosis (HC, PaCO2=60-70 mmHg), ventilated with 5%CO2+21%O2+balancedN2; and (3) buffered hypercapnic acidosis (BHC), ventilated with 5%CO2+21%O2+balancedN2 and treated with sodium bicarbonate (8.4%). The remaining seven animals were not mechanically ventilated (NV). The mRNA expression of interleukin (IL)-6 (p=0.003), IL-1ß (p<0.001), and type III procollagen (PCIII) (p=0.001) in lung tissue was more reduced in the HC group in comparison with NC, with no significant differences between HC and BHC. Lung and kidney cell apoptosis was reduced in HC and BHC in comparison with NC and NV. In conclusion, in this experimental ALI model, hypercapnia, regardless of acidosis, reduced lung inflammation and lung and kidney cell apoptosis.

Immature stages of the Brazilian crescent butterfly Ortilia liriope (Cramer) (Lepidoptera: Nymphalidae).

We provide the first information on the morphology of the immature stages (egg, larva, and pupa), oviposition and larval behavior, and host plant, for the Brazilian crescent butterfly Ortilia liriope (Cramer), based on material from Santarém Municipality, Pará State, Northern Brazil. Females of O. liriope lay eggs in clusters. After hatching, larvae eat the exochorion and remain gregarious in all but the final instar. The host plant recorded in the study site is Justicia sp. (Acanthaceae). Despite the scarcity of data on the immature stages of Neotropical Melitaeini, we can already say that some morphological and behavioral traits observed in the immature stages of O. liriope are also present in all known genera in this tribe.

Morfometria da mucosa duodenal em frangos de corte submetidos à temperatura ambiente cíclica elevada / Intestinal morphometry of the duodenal mucosa in broiler chickens underwent to high cyclic environment temperature

Os efeitos da temperatura ambiente cíclica elevada sobre a morfometria da mucosa duodenal e o peso corporal em frangos de corte foram avaliados. Setenta pintos de corte, machos, foram alojados em gaiolas e distribuídos em dois grupos. Um grupo foi submetido diariamente, durante uma hora, à temperatura ambiente cíclica elevada do primeiro até o 42º dia de idade (ambiente ST); e outro foi mantido em conforto térmico (ambiente TN). Cinco frangos de cada grupo foram sacrificados, semanalmente, por deslocamento cervical para mensuração da altura de vilosidades (VI), profundidade das criptas (CR) e relação vilo/cripta (VI/CR) duodenal. Dez aves de cada grupo foram pesadas semanalmente em balança digital. Utilizou-se delineamento inteiramente ao acaso em esquema fatorial 7x2 (sete idades: um, sete, 14, 21, 28, 35 e 42 dias, e dois ambientes: ST e TN). Os ambientes foram comparados pelo teste de Fisher (P<0,05), e, para avaliar o efeito da idade, foi realizada análise de regressão polinomial. As aves do ambiente ST apresentaram menores VI aos 14 e 21 dias, menor CR aos 28 dias e menor VI/CR aos 21 dias de idade do que as aves do ambiente TN. A temperatura ambiente cíclica elevada teve efeito danoso sobre a estrutura da mucosa duodenal de frangos de corte até a quarta semana de idade e sobre o peso corporal ao final do ciclo produtivo.

The effects of high cyclic environment temperature on body weight and morphometry of the duodenal mucosa in broiler chicken were evaluated. Seventy one-day-old male broiler chicks were sheltered in cages and distributed in two groups. One group was daily exposed to high cyclic environment temperature for an hour, from hatching to 42 days of age (group ST), the other one was kept under thermoneutral conditions (group TN). Five chickens of each group were weekly slaughtered by cervical delocation to mesure the villosities height (VI), crypts depth (CR), and villo/crypt ratio (VI/ CR) in the duodenum. Ten chickens of each group were weighted weekly on a digital balance. A completely randomized experimental design in a 7x2 factorial arrangement (hatching, seven, 14, 21, 28, 35, and 42 days of age and two environments: ST and TN). The environments were compared by Fisher test (P<0.05) and the effects of days of life by polynomial regression. The ST group had reduction in VI at 14 and 21 days of age (P<0.01), CR at 28 days of age (P<0.05), and in VI/CR at 21 days of age (P<0.01). Cyclic high environment temperature had harmful effect on intestinal structure of broiler from hatching to four weeks of age and on body weigh at the end of the productive cycle.

Early short-term versus prolonged low-dose methylprednisolone therapy in acute lung injury.

The present study compared the effects of early short-term with prolonged low-dose corticosteroid therapy in acute lung injury (ALI). In total, 120 BALB/c mice were randomly divided into five groups. In the control group, saline was intratracheally (i.t.) instilled. In the ALI group, mice received Escherichia coli lipopolysaccharide (10 microg i.t.). ALI animals were further randomised into four subgroups to receive saline (0.1 mL i.v.) or methylprednisolone (2 mg x kg(-1) i.v.) at 6 h, 24 h or daily (for 7 days, beginning at day 1). At 1, 3 and 8 weeks, in vivo and in vitro lung mechanics and histology (light and electron microscopy), collagen and elastic fibre content, cytokines in bronchoalveolar lavage fluid and the expression of matrix metalloproteinase (MMP)-9 and -2 were measured. In vivo (static elastance and viscoelastic pressure) and in vitro (tissue elastance and resistance) lung mechanics, alveolar collapse, cell infiltration, collagen and elastic fibre content and the expression of MMP-9 and MMP-2 were increased in ALI at 1 week. Methylprednisolone led to a complete resolution of lung mechanics, avoided fibroelastogenesis and the increase in the expression of MMP-9 and MMP-2 independent of steroid treatment design. Thus, early short-term, low-dose methylprednisolone is as effective as prolonged therapy in acute lung injury.

Muscle-based perception: theory, research and implications for rehabilitation: [review] / Percepção baseada nos músculos: teoria, pesquisa e implicações na reabilitação: [revisão]

BACKGROUND: Muscle-based perception of the spatial properties of limbs constrains the patterning, timing and magnitude of muscle forces while performing motor activities. The centrality of muscle-based perception to both ordinary and skilled actions warrants attention from the rehabilitation community, since deficits in its functioning would be related to important functional limitations. In this overview, we summarize a body of research that may be used to guide the development of effective assessment tools and rehabilitation programs that are specifically directed towards such deficits. OBJECTIVES: There were four specific aims: first, to present an information-based approach to muscle-based perception that is grounded in physical laws; second to identify central principles underlying muscle-based perception that have been revealed and supported by empirical work; third, to summarize reports that have investigated whether the principles identified can be generalized to muscle-based perception in individuals with sensory-motor impairments; and fourth to provide a preliminary discussion of the potential implications of the research presented here for issues relating to rehabilitation.

INTRODUÇÃO: A percepção muscular das propriedades espaciais dos membros restringe o padrão, período e magnitude das forças exercidas durante a execução de atividades motoras. A importância central da percepção muscular, tanto para ações rotineiras quanto para ações especializadas, merece atenção da comunidade envolvida na área de reabilitação, uma vez que alterações em suas funções podem estar relacionadas a importantes limitações funcionais. Nesta revisão, os autores apresentam um resumo da pesquisa que pode ser utilizada para guiar o desenvolvimento de ferramentas de avaliação eficazes bem como programas de reabilitação que sejam especificamente direcionados para estas disfunções. OBJETIVOS: Quatro pontos específicos foram incluídos: primeiro, a apresentação da abordagem com base em informações relativas à percepção muscular de acordo com as leis da física; segundo, a identificação dos princípios centrais determinantes da percepção muscular que vem sendo revelada e apoiada por trabalhos empíricos; terceiro, um resumo dos relatos que investigaram e se os princípios identificados poderiam ser generalizados para a percepção muscular dos indivíduos com alterações motoras e sensitivas; e quarto, uma discussão preliminar sobre as implicações potenciais da pesquisa aqui apresentada, no tocante aos assuntos relacionados à reabilitação.

Changes in lower limb co-contraction and stiffness by toddlers with Down syndrome and toddlers with typical development during the acquisition of independent gait.

During gait acquisition, children learn to use their changing resources to meet the requirements of the task. Compared to typically developing toddlers (TD), toddlers with Down syndrome (DS) have functionally different musculoskeletal characteristics, such as hypotonia, and joint and ligament laxity, that could produce a reduced passive stiffness. The interplay between this inherently lower passive stiffness and the demands of walking may result in different strategies during gait acquisition. This study compared normalized global stiffness and lower limb's co-contraction indices (CCI) used by toddlers with TD (n=12) and with DS (n=12), during the early stages of gait acquisition. Stiffness and CCI were normalized by gravitational torque (mLg) in both phases of gait (stance, swing). Five longitudinal evaluations were conducted from the onset of locomotion until three months post-acquisition. All children were video taped and had electromyographic (EMG) recordings from muscle pairs of one leg, which were used to calculate CCI of hip, knee, ankle, and total leg CCI. Body and lower limb stiffness were calculated according to a hybrid pendulum resonance equation. Results from ANOVAs revealed no group differences on stiffness or on CCI's during stance but children with DS showed greater CCI during swing. Despite the structural musculoskeletal differences between toddlers with TD and with DS, the similarities observed in their processes of gait development suggest functional equivalences.

Avaliação do coeficiente de variação como medida da precisão em experimentos com frangos de corte / Evaluation of the coefficient of variation as a precision measure in experiments with broilers

Estabeleceram-se faixas de coeficientes de variação (CV) que orientem a avaliação de determinadas variáveis em pesquisas futuras. Foram coletados dados de CV de vários trabalhos publicados no Brasil, com ênfase em frangos de corte, abordando: ganho de peso, consumo de ração, conversão alimentar, mortalidade, viabilidade, peso vivo e rendimentos de carcaça, de peito, de pernas, de gordura abdominal, de asas e de dorso. Utilizou-se uma tabela que relaciona mediana (Md) e pseudo-sigma (PS) para estabelecer os intervalos de CV de cada variável. O rendimento de gordura abdominal apresentou faixa de variação com maiores coeficientes de variação; para as demais variáveis, as faixas de classificação dos coeficientes de variação mostraram-se relativamente baixas.

Coefficients of variation (CV) were taken from several researches published in Brazil, with emphasis on broilers performance and their most studied characteristics, such as weight gain, feed consumption, feed:weight gain ratio, mortality, viability, body weight and yields of carcass, breast, legs, abdominal fat, wings and back. The purpose of the study was to establish CV bands which can guide the evaluation of each variable in future experiments. Based on relations between the median (Md) and pseudosigma (PS), a table was created with suggested intervals for the cited parameters. Larger coefficient of variation intervals were observed for abdominal fat yield. The other variables showed relatively low CV interval bands.

A Utilização da dinamometria isocinética nas ciências do esporte e reabilitação / Isokinetic dynamometry in sports and rehabilitation sciences

Aspectos relativos à qualidade dos testes e instrumentos de medida utilizados na prática e pesquisa de profissionais da área de esportes e reabilitação têm ganhado crescente importância. Ao mesmo tempo, os avanços tecnológicos no desenvolvimento de dinamômetro seletromecânicos para a medida da função muscular têm permitido mensurações mais precisas de diversos parâmetros musculares. O objetivo desse trabalho foi descrever as contribuições da dinamometria isocinética para a avaliação do desempenho muscular, bem como considerar fatores importantes para a adequada utilização dessa tecnologia e interpretação dos resultados.Foram revisados e discutidos aspectos referentes ao funcionamento do dinamômetro isocinético, os protocolos de avaliação utilizados, os parâmetros musculares avaliados, a análise dosdados isocinéticos e a interpretação de resultados, considerando questões relativas à confiabilidade e validade dos métodos. Foram ainda discutidas outras possibilidades de teste oferecidaspela dinamometria isocinética além das convencionais e foram feitas considerações sobre otreinamento isocinético. De acordo com a revisão realizada, para interpretação adequada dos resultados, a escolha de protocolos deve ser respaldada pelos dados de confiabilidade relatadosna literatura. Adicionalmente, a realização de testes isocinéticos e a utilização dos dados devem levar em consideração os métodos apropriados de análise e fatores que podem influenciar os resultados. Em relação ao treinamento isocinético, também devem ser consideradas questões funcionais. Quando esses fatores são levados em consideração, a utilização do dinamômetro isocinético é adequada para os propósitos de avaliação, treinamento e pesquisa nas ciências doesporte e reabilitação.

During the last years, aspects relative to the quality of the tests and instruments used by professionals of sports and rehabilitation in practice and research have gained increased importance. Meanwhile, technological advances in the development of electromechanical dynamometers for muscle performance testing have permitted more precise measures of several muscular parameters. The objective of this paper was to describe the contributions of isokinetic dynamometry for assessment of muscle performance, as well as to consider important factors for the adequate utilization of this technology and interpretation of results. Several factors which include functioning of the isokinetic dynamometer, assessment protocols, muscle performance parameters obtained by dynamometry and data analysis and interpretation of results were revised and discussed, considering issues of reliability and validity. Additionally, other possibilities of use for assessment as well as isokinetic training were also discussed. According to the review of the literature, for the adequate interpretation of results, the choice of protocols should be guided by available evidence of reliability. Moreover, isokinetic testing and data utilization should consider the appropriate methods of analysis and the factors that could influence the results. In regard to isokinetic training, functional issues should also be taken into account. Provided that these factors are considered, the utilization of the isokinetic dynamometer is adequate for the purposes of assessment, training and research in the field of sports and rehabilitation sciences.

Influência de práticas maternas no desenvolvimento motor de lactentes do 6º ao 12º meses de vida / Influence of child-rearing practices on infants' motor development between the sixth and twelfth months of life

CONTEXTO: Práticas maternas são comportamentos específicos, por meio dos quais as mães/cuidadores desempenham suas tarefas maternais. Estas práticas poderiam influenciar o desenvolvimento motor de lactentes. OBJETIVO: verificar a influência de práticas maternas, utilizadas no cuidado diário de lactentes saudáveis, sobre seu desenvolvimento motor do 6° ao 12° meses de vida. MÉTODO: Selecionados 14 lactentes, nascidos a termo e saudáveis, avaliados longitudinalmente no 6°, 9° e 12° meses de vida, utilizando-se a Alberta Infant Motor Scale. Em cada avaliação/idade a mãe respondeu a um questionário fechado sobre práticas, predominantemente adotadas no cuidado diário do lactente durante os períodos de vigília. Considerou-se neste estudo a postura predominantemente adotada pelo lactente, local preferencial de permanência e a forma de carregar o lactente no colo. RESULTADOS: No 9° mês de vida o desempenho motor dos lactentes foi influenciado positivamente pela predominância na postura de quatro apoios, em relação à sentada e prono ou supino e pela permanência no chão em relação ao carrinho de bebê. No 12° mês houve influência positiva da predominância na postura de quatro apoios e em pé. A postura predominante no 6° mês de vida e a forma de carregar o lactente no 6°, 9° e 12° meses de vida não influenciaram o desempenho motor do grupo estudado. CONCLUSÃO: Os resultados sugerem que as práticas que estimulam a adoção da postura de quatro apoios e a utilização do chão como local de permanência influenciam positivamente o desenvolvimento motor de lactentes saudáveis a partir do 6° mês de vida.

Ajuste da rigidez muscular via sistema fuso-muscular-gama: implicacoes para o controle da estabilidade articular / Muscle stiffness adjustment through the gamma-spindle system: implications for joint stability control

Diversos estudos biomecanicos tem investigado a importancia das propriedades mecanicas dos musculares para manutencao da estabilidade articular. A rigidez de um musculo ou articulacao esta relacionada a capacidade dessas estruturas de resistirem a pertubacoes. Inumeros estudos tem demonstrado a importancia de um ajuste dinamico da rigidez para manutencao durante atividades funcionais. Dessa forma, um mecanismo neuromuscular que possibilite o ajuste continuo da rigidez muscular permitiria a adaptacao de um individuo a grande variabilidade de demanda de estabilizacao articular existente nos diversos tipos de atividades de vida diaria e esportiva. Foi objetivo desta revisao discutir a adequacao de um mecanismo de ajuste da rigidez via sistema fuso-muscular-gama para o controle da estabilidade articular. Ha evidencias de esse sistema pode ser responsavel pelo aumento na rigidez muscular e articular, o que resultaria em maior habilidade da articulacao em resistir a pertubacoes. Esse mecanismo de ajuste utiliza informacoes extero e proprioceptivas para garantir adaptacao as inesperadas e variadas demandas do ambiente, protegendo as articulacoes contra pertubacoes. O conhecimento dos mecanismos relacionados ao ajuste da rigidez e do papel desse mecanismo na estabilizacao articular seria relevante para Fisioterapia, uma vez que poderia embasar o desenvolvimento de tecnicas de reabilitacao que tenham por objetivo facilitar este ajuste de forma a melhorar a estabilidade funcional dos pacientes