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51.
Trichinellosis is a zoonotic disease affecting people all over the world, for which there is no speedy and reliable treatment. Albendazole (ABZ), an inexpensive benzimidazole used in oral chemotherapy against helminthic diseases, has a broad spectrum activity and is well tolerated. However, the low absorption and variable bioavailability of the drug due to its low aqueous solubility are serious disadvantages for a successful therapy. In this study, we evaluated the in vivo antiparasitic activity of three novel solid microencapsulated formulations, designed to improve ABZ dissolution rate, in a murine model of trichinellosis. Both ABZ and the microparticulate formulations were administered during the intestinal phase of the parasite cycle, on days 5 and 6 post-infection. This protocol significantly decreased muscle larval burden measured in the parenteral phase, on day 30 post-infection, when compared with the untreated control. Moreover, two of the three microencapsulated formulations both strongly and consistently reduced worm burden.  相似文献   
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During the last few years, the development of animal-borne still cameras and video recorders has enabled researchers to observe what a wild animal sees in the field. In the present study, we deployed miniaturized video recorders to investigate the underwater foraging behavior of Imperial cormorants (Phalacrocorax atriceps). Video footage was obtained from 12 animals and 49 dives comprising a total of 8.1 h of foraging data. Video information revealed that Imperial cormorants are almost exclusively benthic feeders. While foraging along the seafloor, animals did not necessarily keep their body horizontal but inclined it downwards. The head of the instrumented animal was always visible in the videos and in the majority of the dives it was moved constantly forward and backward by extending and contracting the neck while travelling on the seafloor. Animals detected prey at very short distances, performed quick capture attempts and spent the majority of their time on the seafloor searching for prey. Cormorants foraged at three different sea bottom habitats and the way in which they searched for food differed between habitats. Dives were frequently performed under low luminosity levels suggesting that cormorants would locate prey with other sensory systems in addition to sight. Our video data support the idea that Imperial cormorants’ efficient hunting involves the use of specialized foraging techniques to compensate for their poor underwater vision.  相似文献   
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Nitric oxide (NO) is a potential new therapeutic agent for sickle cell disease (SCD). We investigated the effects of NO donor on hypoxia-induced acute lung injury that occurs when transgenic sickle cell SAD mice are exposed to chronic hypoxia, a model for lung vasoocclusive sickle cell events. In wild-type and SAD mice, intraperitoneal injection of S-nitrosoalbumin (NO-Alb) produced no significant hematologic changes under room air conditions, whereas it induced mild temporary hypotension and inhibition of platelet aggregation. NO-Alb administration (300 mg/kg ip twice a day, equivalent to 7.5 microM NO) in wild-type and SAD mice exposed to 46 h of hypoxia (8% oxygen) followed by 2 h of normoxia resulted in 1) reduction of the hypoxia-induced increase in blood neutrophil count, 2) prevention of hypoxia-induced increased IL-6 and IL-1beta levels in bronchoalveolar lavage, 3) reduction of the lung injury induced by hypoxia-reoxygenation, 4) prevention of thrombus formation, and 5) prevention of hypoxia-induced increase of lung matrix metalloproteinase-9 gene expression. These effects provide new insights into the possible use of NO-Alb in the treatment of acute lung injury in SCD.  相似文献   
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The objective of this study was to analyze the spatial and temporal dynamics of Chironomidae larvae assemblages in a subtropical mountain river basin of northwestern Argentina. We hypothesized that they would respond to (1) environmental changes along the altitudinal gradient in the Yungas forests; (2) environmental changes caused by spates (e.g., increased discharge or sediment transportation). We sampled five sites along an altitudinal gradient of ca. 1,500 m (from 680 to 2,170 m) during low-water and high-water period for 2 years. The Chironomidae larvae assemblages varied along the altitudinal gradient and between sampling periods based on an indicator species analyses and an ordination analyses (NMDS). The best indicator for high altitude sites was “Genus X” followed by Onconeura sp.2, “Genus 9”, “Genus 10”, and Rheotanytarsus sp.2; while Rheotanytarsus lamellatus, Oliveiriella sanjavieri, and Thienemanniella sp. were good indicators for low altitude sites. O. sanjavieri and R. lamellatus were the best indicators for high-water period. The most relevant environmental variables influencing their spatial and temporal distribution were altitude, water temperature, conductivity, and pH. This study is the first to analyze and describe in detail the spatial and temporal distribution of Chironomidae larvae assemblages in northwestern Argentina, and most of the taxa reported here are new records for the region.  相似文献   
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We studied the impact of a food supplementation program (Plan Más Vida (PMV)) on the micronutrient nutritional condition of pregnant women from low-income families 1 year after its implementation. The food program provided supplementary diet (wheat and maize—fortified flour, rice or sugar, and fortified soup). We performed a prospective, nonexperimental, cross-sectional study in the province of Buenos Aires, Argentina, evaluating pregnant women at baseline (n?=?164) and 1 year after PMV implementation (n?=?108). Biochemical tests (hemogram, ferritin, vitamin A, zinc, and folic acid), anthropometric assessments (weight and height), and dietary surveys (24 h recall) were performed at the two study points. One year after PMV implementation, no significant changes in anthropometric values were observed. Folic acid deficiency and the risk of vitamin A deficiency (retinol, 20–30 μg/dl) decreased significantly (35.8 to 6.1 % and 64 to 41 %, respectively; p?<?0.000). Anemia and prevalence of iron and zinc deficiency values did not change. Diet survey results showed that although nutrient intake increased significantly, it was still below recommendations. Implementation of the PMV and of the government nutritional strategies had a high impact on the prevalence of folic acid deficiency. We also observed a decrease in the risk of vitamin A deficiency, and no impact on iron and zinc nutritional status. Adherence to the specific fortified food (soup) was not good and intra-family dilution and distribution of food was high.  相似文献   
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This study was undertaken to evaluate the impact of Plan Más Vida (PMV) on the micronutrient nutritional condition of children aged 1 to 6?years 1?year after PMV implementation. The food program was intended for low-income families from the province of Buenos Aires, Argentina and provided supplementary diets. A prospective, nonexperimental study was carried out. Children (472 at baseline and 474 after 1?year) were divided into two groups (1-2 and 2-6?years of age). Biochemical tests (hemogram, ferritin, zinc, vitamin A, and folic acid), anthropometric assessments (weight and height), and dietary surveys (24-h recall) were performed. Chronic growth retardation (-2 height/age Z-score) was present in 2.8% and 8.7% of 1-2- and 2-6-year-old children, respectively; 14.4% in the former and 8.8% in the latter group had overweight/obesity. No significant changes were recorded 1?year after PMV implementation. Whereas anemia values decreased (55.3% to 39.1%, p?=?0.003) and serum zinc values increased in 1-2-year-old children, the risk for vitamin A deficiency decreased significantly in both age groups. The evaluation of the early impact of PMV actions provided important nutritional data that should be used by provincial health authorities to conduct future evaluations.  相似文献   
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The way in which animals use and acquire energy is fundamental to their fitness. Overall dynamic body acceleration (ODBA) has recently been suggested as a new method for the determination of energy expenditure in wild animals. Although the relationship between ODBA and energy expenditure has been calibrated using gas-respirometry, it has only been validated for animals moving in a single medium. In this work we examined whether the relationship between ODBA and energy expenditure varies between activity types and in particular, how locomotion in different media affects the regressions using the Imperial Cormorant Phalacrocorax atriceps as a model species. Regressing mean ODBA values for resting, diving and walking periods on a single graph against mean power values, the mass-specific power (W kg−1) was related to ODBA via; Power = 12.09 + 41.31 ODBA (r2 = 0.93). Although values for resting, walking and swimming all fell close to a single linear fit, values for flight deviated substantially from this. The different relationships found between locomotory types are discussed in terms of the muscle groups involved in each kind of behavior.  相似文献   
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