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31.
As a result of population migration, Chagas disease is no longer limited to the North and South American continents. In HIV-infected patients, chronic infection by Trypanosoma cruzi behaves as an opportunistic infection in severely immunosuppressed patients and is responsible for high morbidity and mortality. Unlike other opportunistic infections, information on the natural history, diagnosis, treatment, and prevention of Chagas disease is scarce. Spain has the highest number of cases of Chagas disease outside the North and South American continents, and coinfection with HIV is increasingly prevalent. In this article, the Spanish Society for Tropical Medicine and International Health (Sociedad Espa?ola de Medicina Tropical y Salud Internacional) reviews the current situation of coinfection with HIV and T. cruzi infection and provides guidelines on the diagnosis, treatment, and prevention in areas where Chagas disease is not endemic. It also identifies areas of uncertainty where additional research is necessary.  相似文献   
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Neutrophil accumulation in the first hour of myocardial reperfusion was assessed in dog hearts submitted to ischemia with and without necrosis. In anesthetized dogs, the left anterior descending coronary artery was occluded for 20 min (group IS-20 n = 7) and for 90 min (group IS-90 n = 6). Immediately after reperfusion, 99m Tc-Ceretec (Exametazime-Amersham) labeled neutrophils were injected into a central vein and 60 min later the dogs were killed. The left ventricle was isolated, weighed, and sliced. Six sections, 3 from normal and 3 from reperfused regions, were divided into endocardial and epicardial layers. Myocardial and blood radiometry were used to evaluate the neutrophil accumulation during reperfusion. The differences between leukocyte accumulation in both groups were assessed comparing the ischemic/normal relations in the endocardial and epicardial layers. A second comparison considered myocardium/blood relations to allow the evaluation of differences between remote normal myocardial areas of the two experimental groups. In dogs submitted to 20 min of ischemia, leukocytes accumulated significantly more (P < 0.01) in the reperfused myocardium as compared with the non-ischemic region. The increase occurred both in the endocardial (1.49+/-0.20) and epicardial (1.48+/-0.29) regions. After 90 min ischemia, leukocyte accumulation was more intense and predominant in endocardium where there was a 4-fold (3.97+/-1.28) increase over the non-ischemic region, while in the epicardium this relation was only 2.5-fold (2.56+/-0.98). In the remote non-ischemic myocardium, leukocyte accumulation was greater in dogs submitted to 90 min of ischemia compared to the 20 min group (P < 0.01), without distinction between endocardial and epicardial layers. This accumulation in territories of non-culprit coronary arteries may be related to the blood flow abnormalities and matrix structure changes that occur in these regions during the development of an acute myocardial infarction and its natural repair.  相似文献   
35.
Consumption of foods rich in phytoestrogens such as flaxseed has increased due to its chemoprotective effects, especially those related to the cardiovascular system. The flaxseed has components that can interfere with development of male reproductive system. This study aims to investigate the possible effects of prolonged consumption of flaxseed flour on hormonal and histomorphologic penis parameters of adult Wistar rats. Rat dams were divided into two groups during lactation period: the control group that was fed with diet based on casein and the flaxseed group that was fed with diet based on casein containing 25% of flaxseed . At weaning, 10 male offspring from each group continued to receive the experimental diets until 250 days old. Rats fed with diet containing flaxseed showed increased concentrations of 17β-estradiol (p = 0.01) but no changes in testosterone concentrations. With regard to histomorphometric analysis of the penis, supplemented rats had lower values for the total area of the corpus spongiosum (p = 0.01). All other analyzed parameters wer e similar as the control. Results showed that the use of flaxseed flour did not cause adverse effects on the penis morphology but increases the 17β-estradiol hormone, when consumed in integral form for a prolonged period.  相似文献   
36.
The mechanism by which the salivary gland lysate (SGL) of Lutzomyia longipalpis enables Leishmania infection remains under investigation. One possibility is that saliva promotes cellular recruitment leading to development of skin lesions. In this study, we investigated leukocyte recruitment induced by L. major, L. major + SGL, or SGL alone into the peritoneal cavity of BALB/c mice. The administration of L. major with or without SGL induced neutrophil migration six hours after infection. Interestingly, after seven days, the BALB/c mice still had eosinophils and mononuclear cells in their peritoneal cavities. Flow cytometric analysis showed an increase in the CD4(+) CD45RB(low) T cell subset (effector or memory cells) compared with the CD4(+) CD45RB(high) subset (naive cells). Moreover, the co-injection of L. major with SGL enhanced production of interleukin-10. These results suggest that SGL can facilitate Leishmania infection by modulating leukocyte recruitment and Th2 cytokine production at the inflammatory focus.  相似文献   
37.
Cutaneous larva migrans is a pruritic dermatitis due to the inoculation of helminthslarvae in the skin, and it often occurs in children in tropical and subtropicalareas. The authors describe an atypical case of cutaneous larva migrans in a 11year-old child with scalp involvement, an unusual topography for this lesion.  相似文献   
38.
Abstract

As a result of population migration, Chagas disease is no longer limited to the North and South American continents. In HIV-infected patients, chronic infection by Try-panosoma cruzi behaves as an opportunistic infection in severely immunosuppressed patients and is responsible for high morbidity and mortality. Unlike other opportunistic infections, information on the natural history, diagnosis, treatment, and prevention of Chagas disease is scarce. Spain has the highest number of cases of Chagas disease outside the North and South American continents, and coinfection with HIV is increasingly prevalent. In this article, the Spanish Society for Tropical Medicine and International Health (Sociedad Española de Medicina Tropical y Salud Interna-cional) reviews the current situation of coinfection with HIV and T. cruzi infection and provides guidelines on the diagnosis, treatment, and prevention in areas where Cha-gas disease is not endemic. It also identifies areas of uncertainty where additional research is necessary.  相似文献   
39.
This study was performed to evaluate the compressive mechanical strength of rigid internal fixation (RIF) using 1.5-mm L-shaped plates fixed with monocortical screws in sagittal split osteotomy (SSO). Thirty synthetic hemimandibles, which had all undergone a 5-mm advancement, were divided into three groups: three 12-mm bicortical titanium screws were placed in an inverted L pattern in group A; one straight 2.0-mm system spaced titanium plate fixed with four 5-mm monocortical screws was used in group B; two 1.5-mm system L-shaped titanium plates, each fixed with four 5-mm monocortical screws, were used in group C. The models were subjected to compressive and progressive mechanical tests with forces applied in the area between the second premolar and first molar to verify resistance in Newtons (N). A displacement speed of 1 mm/min was applied, with a maximum 10 mm displacement of the distal segment or until disruption of the fixation. The deformity and/or eventual rupture of the plates were evaluated, and consequently their technical stability was determined. The results showed that the modified fixation technique tested in this study on synthetic mandibles resulted in adequate stability and superior mechanical behaviour compared to simulated osteosynthesis with the use of a straight 2.0-mm titanium plate.  相似文献   
40.
The corpus cavernosum (CC) extracellular matrix is essential for normal penile erection and is implicated in erectile dysfunction. Although investigations of these issues have used the rabbit CC, organization of its components is not well known to date. We characterized and quantified the volumetric density (Vv) of the elastic system fibers in the corpus spongiosum (CS), CC and tunica albuginea (TA) of the rabbit penis. Adult New Zealand rabbits (n = 10) were used. The penile mid-shaft fragments were fixed with 4% phosphate-buffered formalin solution and/or Bouin's liquid for 24-48 h, and processed using standard histological techniques. The sections were stained with Weigert's Fucsin-Resorcin with previous oxidation. The elastic system fibers Vv (%) was determined in 25 random fields of each fragment, using the M-42 test grid. The histochemical methods detected elastic system fibers in CS, CC and TA of all animals. The Vv of elastic fibers average was 25.03+/-2.0% for CC, 32.23+/-1.41% for CS and 22.38+/-3.61% for TA. Results for CC and CS were not significantly different. The great amount of elastic fibers distribution beneath the endothelium suggest that these fibers may have an important role in the erection process in rabbits. The present data should therefore provide important information for devising experiments and interpreting results when using the rabbit penis as a model for penile dysfunctions, especially when making comparisons with humans.  相似文献   
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