Exposure of Phosphatidylserine on Leishmania amazonensis Isolates Is Associated with Diffuse Cutaneous Leishmaniasis and Parasite Infectivity

Diffuse cutaneous leishmaniasis (DCL) is a rare clinical manifestation of leishmaniasis, characterized by an inefficient parasite-specific cellular response and heavily parasitized macrophages. In Brazil, Leishmania (Leishmania) amazonensis is the main species involved in DCL cases. In the experimental model, recognition of phosphatidylserine (PS) molecules exposed on the surface of amastigotes forms of L. amazonensis inhibits the inflammatory response of infected macrophages as a strategy to evade the host immune surveillance. In this study, we examined whether PS exposure on L. amazonensis isolates from DCL patients operated as a parasite pathogenic factor and as a putative suppression mechanism of immune response during the infection. Peritoneal macrophages from F1 mice (BALB/c×C57BL/6) were infected with different L. amazonensis isolates from patients with localized cutaneous leishmaniasis (LCL) or DCL. DCL isolates showed higher PS exposure than their counterparts from LCL patients. In addition, PS exposure was positively correlated with clinical parameters of the human infection (number of lesions and time of disease) and with characteristics of the experimental infection (macrophage infection and anti-inflammatory cytokine induction). Furthermore, parasites isolated from DCL patients displayed an increased area in parasitophorous vacuoles (PV) when compared to those isolated from LCL patients. Thus, this study shows for the first time that a parasite factor (exposed PS) might be associated with parasite survival/persistence in macrophages and lesion exacerbation during the course of DCL, providing new insights regarding pathogenic mechanism in this rare chronic disease

Jaw Laterality and Related Handedness in the Hunting Behavior of a Scale-Eating Characin, Exodon paradoxus

BACKGROUND: Asymmetry in animal bodies and behavior has evolved several times, but our knowledge of their linkage is limited. Tanganyikan scale-eating cichlids have well-known antisymmetry in their bodies and behavior; individuals open their mouths leftward (righty) or rightward (lefty), and righties always attack the right flank of the prey, whereas lefties attack the left. This study analyzed the morphological asymmetry in a scale-eating characiform, Exodon paradoxus, and its behavioral handedness. METHODOLOGY/PRINCIPAL FINDINGS: Each eight E. paradoxus was observed for 1-h with a prey goldfish in an aquarium to detect the behavioral handedness. Following the experiment, the lateral differences in the mandibles and head-inclination of these eight and ten additional specimens were analyzed. Both measurements on the morphology showed a bimodal distribution, and the laterality identified by these two methods was always consistent within a given individual, indicating that the characin has morphological antisymmetry. Furthermore, this laterality significantly corresponded to behavioral handedness; that is, lefties more often rasped scales from the right flank of the prey and vice versa. However, the correlation between laterality and handedness is the opposite of that in the cichlids. This is due to differences in the feeding apparatus and technique. The characin has cuspids pointing forward on the external side of the premaxilla, and it thrusts its dominant body side outward from its body axis on the flank of the prey to tear off scales. By contrast, the cichlids draw their dominant body side inward toward the axis or rotate it to scrape or wrench off scales with the teeth lined in the opened mouth. CONCLUSIONS/SIGNIFICANCE: This study demonstrated that the antisymmetry in external morphology and the corresponding behavioral handedness have evolved in two lineages of scale-eating fishes independently, and these fishes adopt different utilization of their body asymmetry to tear off scales

Estado nutricional, consumo alimentar e risco cardiovascular: um estudo em universitários Nutritional status, food consumption and cardiovascular risk: a study on university students

OBJETIVO: Descrever a proporção de fatores de risco para doenças cardiovasculares, dando ênfase aos fatores nutricionais, em alunos da área de saúde de uma universidade pública do Recife. MÉTODOS: Foram avaliados 250 estudantes por um questionário que abordou aspectos biossociais, dados sobre estilo de vida, história familiar para doenças cardiovasculares, variáveis antropométricas e consumo alimentar, avaliado pelo Recordatório de 24horas. RESULTADOS: Foi encontrada a seguinte freqüência para os fatores de risco analisados: tabagismo (2,8%), sedentarismo (41,7%), excesso de peso (35,5% e 5,3% nos sexos masculino e feminino, respectivamente p<0,01), história familiar de hipertensão (35,5%), diabetes (11,3%) e obesidade (20,2%), morte antes dos 50 anos por doenças cardiovasculares nos familiares diretos (14,8%). Com relação ao consumo alimentar, observou-se um elevado percentual de inadequação no consumo de energia e um baixo percentual de inadequação no consumo de proteínas e carboidratos. Quanto ao perfil lipídico da dieta, mais de 40,0% dos estudantes apresentaram consumo de colesterol acima do recomendado e, em 17,9% dos homens e 44,8% das mulheres foi evidenciado um elevado consumo de gordura saturada (p<0,01). O consumo de ácido linoléico, ácido graxo monoinsaturado e poliinsaturado mostrou-se insuficiente em mais de 95,0% dos indivíduos estudados. CONCLUSÃO: A alta proporção de fatores de risco cardiovasculares representa uma advertência, dada a juventude da população considerada, e mostra a necessidade de insistir em medidas educativas e de promoção de condutas preventivas.<br>OBJECTIVE: This study aimed to describe the proportion of risk factors for cardiovascular diseases, emphasizing nutritional factors, among health students from a public university in Recife, Brazil. METHODS: Two hundred and fifty students were assessed through a questionnaire that addressed biosocial aspects, lifestyle data, family history for cardiovascular diseases, anthropometric variables and food consumption determined by the 24-hour recall. RESULTS: The following rates were found for the assessed risk factors: smoking (2.8%), inactivity (41.7%), overweight (35.5% among men and 5.3% among women, p<0,01), family history of hypertension (35.5%), diabetes (11.3%), obesity (20.2%) and death of close relatives before age 50 due to cardiovascular diseases (14.8%). Regarding food consumption, a high percentage of individuals had inappropriate energy intake and a low percentage had inappropriate protein and carbohydrate intakes. Regarding the fat profile of the diet, more than 40.0% of the students consumed more cholesterol than the recommended levels and 17.9% of the men and 44.8% of the women consumed high amounts of saturated fat (p<0.01). The consumption of linoleic acid and monounsaturated and polyunsaturated fatty acids was inadequate in more than 95% of the individuals under study. CONCLUSION: The high rates of risk factors are a warning sign, given the young age of the studied population, and show the need to insist on measures to prevent primary cardiovascular disease