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The aim of this study was to investigate the association between foot type and the morphometry of selected muscles and tendons of the lower limb. Sixty-one healthy participants (31 male, 30 female; aged 27.1 ± 8.8 years) underwent gray-scale musculoskeletal ultrasound examination to determine the anterior-posterior ( AP) thickness of tibialis anterior, tibialis posterior, and peroneus longus muscles and tendons as well as the Achilles tendon. Foot type was classified based on arch height and footprint measurements. Potentially confounding variables (height, weight, hip and waist circumference, rearfoot and ankle joint range of motion, and levels of physical activity) were also measured. Multiple linear regression models were used to determine the association between foot type with muscle and tendon morphometry accounting for potentially confounding variables. Foot type was significantly and independently associated with AP thickness of the tibialis anterior tendon, peroneus longus muscle, and Achilles tendon, accounting for approximately 7% to 16% of the variation. Flat-arched feet were associated with a thicker tibialis anterior tendon, a thicker peroneus longus muscle, and a thinner Achilles tendon. Foot type is associated with morphometry of tendons that control sagittal plane motion of the rearfoot; and the peroneus longus muscle that controls frontal plane motion of the rearfoot. These findings may be related to differences in tendon loading during gait. [ABSTRACT FROM AUTHOR]

The variations of the nucleolar characteristics size and number were studied in the gill and liver of Odontesthes bonariensis under different feeding regimes in order to test the hypothesis that functional genomes at the nucleolus, which determine variation of size (heterogeneity) in juvenile fishes, are modulated by environmental factors such as food availability. The programme that controls genetic changes of the nucleolar characteristics of the diploid cells of O. bonariensis was different from that described in the diploid cells of cyprinid fishes. No variations of the mean nucleolar number per nucleus were observed in liver or gill cells in relation to the feeding regime. Conversely, significant reduction of the mean nucleolar volume per nucleus ( VMN) and change in the shape of the frequency distribution of the total nucleolar volume per cell was evident in both cell types in response to starvation or food restriction. Tissue specificity was observed in relation to the absolute values of the nucleolar characteristics; however, the relative behaviour was comparable in digestive and non-digestive tissues. The time-course reduction of VMN in gill and liver cells of restrictively fed fish followed a negative exponential. A good correlation between VMN and the condition index of the fish ( K) was observed after long-term food restriction; however, a faster response of VMN was observed after short-term fasting events. Results supported the stated hypothesis and showed nucleolar activity as a direct, rapid and sensitive indicator of the nutritional status of the fish. [ABSTRACT FROM AUTHOR]

The geographic distribution and frequency of Bos taurus and Bos indicus Y chromosome haplotypes amongst Argentine and Bolivian Creole cattle breeds were studied, using cytogenetic and molecular genetic techniques. A complete correspondence between Y chromosome morphology and the haplotype of the Y-linked microsatellite marker INRA 124 was found in all males examined. The taurine and indicine haplotypes were detected in 85·7 and 14·3% of the males studied, respectively, although these frequencies varied amongst the different breeds examined. The geographic distribution of this polymorphism suggests a pattern of zebu introgression in South America. The highest frequencies of the Zebu Y-chromosome are found in Brazilian populations (43–90%), in the eastern part of the continent, while it is absent in the southermost breeds from Uruguay and Argentina. Bolivan breeds, at the centre of the continent, exhibit intermediate values (17–41%). This east/west and north/south gradient of male Zebu introgression could be explained by historical events and environmental factors. [ABSTRACT FROM AUTHOR]

Many biological and anthropological investigations have described the role between mass-to-surface area index (M/SA) and heat tolerance. No large M/SA database exists that can be used as a reference standard to interpret previous or future M/SA studies. This report presents the M/SA data of a large military cohort (1,170 males aged 17-54 years, 305 females aged 17-40 years). The effects of gender, ethnic group, and age on the distribution of M/SA, as well as the relationship between M/SA and other physical characteristics, were described. It was observed that the increases of M/SA with increasing age (over the 17-75 years category) were not significant. All descriptive characteristics (including M/SA) were different (P less than .001) between males and females. M/SA was not statistically different between ethnic groups among both males and females. These data may be utilized to compare the M/SA values of U.S. citizens to those of other ethnic groups and to identify those laborers or athletes who possess the greatest theoretical risk of heat intolerance.