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101.
An estimated 400 million people are infected by parasites of the genus Ascaris and the existing control measures are inefficient. Vaccine development using B cell antigens is a promising strategy for increased protection against this parasite. The present study aimed at developing a chimeric protein capable of conferring protection against infection by Ascaris sp. For this purpose, we performed B-cell epitope predictions on previously described vaccine candidate proteins from Ascaris suum and the corresponding peptides were used to construct a chimeric protein. Female BALB / c mice were immunized subcutaneously in three doses at 10 day intervals with a vaccine formulation comprised of the chimeric protein together with monophosphoryl lipid A (MPLA). Control groups included protein alone, MPLA, or PBS. After challenge infection, animals vaccinated with chimeric protein plus MPLA showed a reduction of 73.54% of larval load in the lung compared to control group animals. Animals immunized with chimeric protein plus MPLA also display higher IgG response and a reduction in lung inflammation. Our study highlights how chimeric proteins containing more than one B cell epitope can enhance immune protection against helminthic infection and offer new approaches to the development of Ascaris vaccines.  相似文献   
102.
Journal of Public Health - Adolescents’ sleep duration has decreased over the past century; this is mainly caused by problems with falling asleep. Short sleep duration, poor sleep quality,...  相似文献   
103.
European Journal of Clinical Microbiology & Infectious Diseases - The aim of this study is to evaluate the chlorhexidine gluconate (CHG) susceptibility in both planktonic cells and biofilm of...  相似文献   
104.
An attempt was made to control cutaneous leishmaniasis in the municipality of Santa Leopoldina, Espírito Santo State, Brazil, by treating infected dogs. Another area in the municipality of Afonso Cláudio, which is ecologically similar, served as the control area, and dogs were left untreated there. In an initial survey, 34/141 inhabitants of the first area had positive leishmanin tests and 8/26 dogs had cutaneous leishmaniasis, while in the second area 37/127 individuals had positive leishmanin tests and 7/44 dogs were infected. After treatment of the sick dogs in the first area the populations of both areas were periodically examined for new infections. More new human infections were observed in the control area, but the difference was not statistically significant.  相似文献   
105.
The present study was undertaken to analyse the relationship between postnatal development of vascular 2-adrenoceptor-mediated responses and the content of adrenaline in the adrenal gland and its concentration in plasma. Dog saphenous vein tissue from newborn, two-weeks old and adult animals were either preloaded with 3H-noradrenaline (or 3H-adrenaline) to study prejunctional -adrenoceptor-mediated effects or mounted in organ baths to determine isoprenaline-induced relaxation of preparations contracted by phenylephrine to about 65010 of the maximum. The adrenal glands and samples of blood from the same animals were taken for estimation of adrenaline and noradrenaline.At birth, there were no -adrenoceptor-mediated effects pre- or postjunctionally. At two weeks, while the results at the prejunctional level were not significantly different from those obtained in newborns, at the postjunctional level there was a relaxant response to isoprenaline, which antagonised about 35010 of the previous contraction to 1.75 mol·l–1 phenylephrine. In adults, isoprenaline (50 nmol·l–1) increased by 24% tritium overflow evoked by electrical stimulation of tissues preloaded with 3H-noradrenaline but not that of tissues preloaded with 3H-adrenaline. On the other hand, propranolol (1 mol·l–1) reduced by 21% the overflow of tritium evoked by electrical stimulation of tissues preloaded with 3H-adrenaline but not that of tissues preloaded with 3H-noradrenaline; postjunctionally, the maximal response to isoprenaline antagonised 70% of the previous contraction to 1.75 mol·l–1 phenylephrine.At birth the catecholamine content of the adrenals was relatively low (2.9 ol·g–1) and the adrenaline/noradrenaline ratio was 0.26; two weeks later, the catecholamine content was 14.5 mol·g-1and the adrenaline/noradrenaline ratio was 0.74; in adults, the catecholamine content was 24.5 mol·g–1 and the adrenaline/noradrenaline ratio was 2.3. In plasma, the highest concentration of adrenaline was observed at birth (11.8 nmol·l–1); two weeks later it was 5.5 nmol·l–1 and in adulthood it fell to 3.1 nmol·l–1.On the basis of these results, it is concluded that some link between the postnatal increase in adrenaline adrenal content and the development of 2-adrenoceptor-mediated pre- and postjunctional effects may exist. Additionally it is suggested that circulating adrenaline may trigger the development of 2-adrenoceptor-mediated responses as well as some hypertensive states occurring as a consequence of an overreactivity of the sympathoadrenal system. Correspondence to: S. Guimarães at the above address  相似文献   
106.
107.
This paper seeks to review the epidemiological aspects of the acquired immunodeficiency syndrome (AIDS) in children and the vertical transmission of the human immunodeficiency virus (HIV). The modes of mother-to-infant transmission are discussed, including physiopathological aspects of HIV infection in utero, during, and/or after delivery.  相似文献   
108.
An evaluation is made of the effect of smoking during the period of life between 20 and 50 years of age and idiopathic Parkinson's disease in a case-control study carried out in Navarra. An inverse association is observed: for the number of smokers (OR = 0.66, CI 90% 0.41-1.05); for the number of years smoking (OR =0.22, CI 90% 0.05-0.97); and for the quantity of cigarettes smoked (z = 2.2298, p = 0.02). Likewise, a dose-response relationship exists between the number of cigarettes consumed and the risk of Parkinson's disease (p = 0.01). The same effect is maintained on analysing the data by matching 1:1 (OR = 0.59, CI 90% 0.31-1.10). All of this contributes to giving consistency to the protective effect of smoking against idiopathic Parkinson's disease. The anti-oxidant status, measured by means of different parameters in peripheral blood, is lower in the cases than in the tests for reduced glutathione (GSH) (p = 0.001) and is an independent variable with respect to smoking.  相似文献   
109.
Lapachol is a naphtoquinone with therapeutic potential against Chagas disease and is also used as an antimalarial agent. To study the reproductive toxicity potential of Lapachol, pregnant Wistar rats were treated with 0.5 mL of distilled water (control group), 0.5 mL of hydroalcoholic solution (vehicle group), or 20 mg of Lapachol in 0.5 mL of hydroalcoholic solution (treated group) by oral gavage from the 8th to the 12th day of pregnancy. The following variables were observed: maternal body weight on days 1, 6, 15, and 21; food intake on days 2, 6, 15, and 21 of pregnancy. The number of live and dead fetuses and the sites of resorptions were counted. The ovaries were weighed and the corpora lutea were counted. Data were analyzed by ANOVA one-way Dunnett test and chi 2 test. Results showed that mothers were uneffected but there was 100% fetal/embryo mortality, indicative of a strong interceptive effect of Lapachol in rats.  相似文献   
110.
Anemia is estimated to affect half the school-age children and adolescents in developing countries. The main causes are parasitic infections, malaria, and low iron intake. This study aimed to describe the prevalence of anemia, parasitic infections, and nutritional status of children attending public primary schools in Aracaju, Northeast Brazil. Of 360 students, 26.7% were anemic, and prevalence was higher in children under 8 and over 15 years of age. Overall prevalence of intestinal parasites was 42%, with Ascaris lumbricoides (28.7%), Trichuris trichiura (15.6%), and hookworm (1. 7%) most frequently found. There was an association between parasitic infections and poor sanitary conditions, but there was no association between anemia and presence of intestinal parasites. Height-for-age Z scores were lower than the NCHS standard, and prevalence of stunting was 5.4%. Although intestinal parasites were not associated with anemia, children with parasites had lower nutritional indices (weight- and height-for-age Z scores) than those without parasites.  相似文献   
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