Experimental neurocysticercosis: absence of IL-4 induces lower encephalitis.

METHODS: BALB/c (WT) and BALB/c (IL-4-KO) mice were inoculated intracranially with Taenia crassiceps cysticerci and euthanized at 7, 30, 60 and 90 days later, the encephala removed and histopathologically analyzed. RESULTS: The absence of IL-4 induced greater parasitism. In the initial phase of the infection, IL-4-KO showed a lower intensity in the inflammatory infiltration of polimorphonuclear cells in the host-parasite interface and intra-parenquimatous edema. The IL-4-KO animals, in the late phase of the infection, showed lower intensity of ventriculomegaly, encephalitis, and meningitis, and greater survival of the parasites in comparison with the WT animals. CONCLUSION: The absence of IL-4 induced lower inflammatory infiltration, ventriculomegaly and perivasculitis in experimental NCC.

Low intensity ultrasound therapy induces angiogenesis and persistent inflammation in the chronic phase of the healing process of third degree burn wounds experimentally induced in diabetic and non-diabetic rats.

PURPOSE: To evaluate the effects of low intensity ultrasound on the healing process of third degree burn wounds in experimentally induced diabetic Wistar rats. METHODS: One hundred rats were divided into: control group; non-diabetic treated group; diabetic control group; diabetic treated group. The therapy was performed with a 3MHz ultrasound application, pulsed emission at 100Hz frequency, modulated at 20% with a dosage of 0.5W/cm2 during three minutes throughout 30 days. The surgical debridement of the wound was performed once at day 2. The wounds were morphometrically, macroscopically and microscopically evaluated at 3, 7, 14, 21 and 30 days. RESULTS: The wound contraction and collagen quantification were higher in all treated groups. Macroscopically, necrosis was higher in the diabetic control group. Granulation tissue was higher in treated groups during the proliferative and remodeling phase. Microscopically, there were greater mononuclear inflammatory infiltration, angiogenesis and fibroblast quantification in treated groups during the proliferative and remodeling phases. CONCLUSIONS: therapeutic ultrasound is beneficial in the inflammatory and proliferative phases of the healing process because it controlled the necrotic tissue, increased the granulation tissue and wound contraction. However in the remodeling phase it is not beneficial because of the continued angiogenesis and a mononuclear inflammatory infiltration.

The effect of carbon dioxide therapy on composite graft survival.

PURPOSE: To investigate the effect of carboxytherapy in auricular composite grafts in rabbits. METHODS: An experimental study was conducted using 20 rabbits randomly assigned to a treatment group of carboxytherapy or a control group of saline solution. In each ear, a circular graft with 1.5 cm or 2 cm of diameter was amputated and reattached. Animals underwent carbon dioxide or saline injection four times during the experiment. We analyzed clinical evolution of the animals, grafts survival, histopathology features and histomorphometry of collagen. RESULTS: The treated group had a significantly lower weight gain (p=0.038). Histopathology was not significantly different between groups. There was an increase in amount of collagen in 2 cm grafts submitted to carbon dioxide therapy (p=0.003). Carboxytherapy didn't influence graft survival rate for 1.5 cm grafts or 2 cm grafts (p=0.567 and p=0.777, respectively). CONCLUSIONS: Carbon dioxide therapy increased the amount of collagen in 2 cm grafts. CO2 was not significantly different from saline infusion on composite grafts survival, but this study suggests that there is a mechanical effect caused by distension which favored graft survival.

Causes of death in older people autopsied.

Studies of causes of death in autopsied older people are not common in Brazil. The aims were to compare demographic data and causes of death in elderly people autopsied in the 1970s, 1980s, and 1990s and to relate causes of death to age, sex, color, and body mass index. Data survey of the autopsy reports came from the Hospital de Clínicas of the Universidade Federal do Triângulo Mineiro, Uberaba, Minas Gerais, Brazil. The data were obtained from the autopsied individuals 60 years or older. Median age was 69 years (60-120 years) and was higher in the 1990s than in the 1970s (70.5 vs 68.0, P < .05) and higher in women (70 vs 68 years, P < .05). Men (66.8%) and white people (70.0%) predominated during the period. The most frequent causes of death were cardiovascular (42%) and infectious (33.4%). The percentage of cardiovascular causes of death varied little over the 1970s (41.7%), 1980s (42.3%), and 1990s (42.9%), whereas that of infectious causes decreased (38.0%, 28.6%, and 28.6%, respectively) and that of neoplastic causes increased (10.3%, 12.6%, and 19.6%, respectively, P > .05). Most of the elderly (84.6%) presented a body mass index of less than 22 kg/m2 and malnutrition predominated in the 1980s (48%). Therefore, there was little percentage variation in cardiovascular-related deaths over the 3 decades while the percentage of neoplastic-related deaths increased. Infectious causes of death was associated with the lowest body mass index, and the greatest percentage of cardiovascular and neoplastic-related deaths were in women.

Anatomopathological study in BALB/c mice brains experimentally infected with Toxoplasma gondii.

Toxoplasmosis is one of the most important diseases of the nervous central system, leading to severe symptoms and, many times, irreversible sequelae. This work demonstrated the main anatomopathological lesions caused by Toxoplasma gondii in brains from experimentally infected BALB/c mice. We analyzed 51 cases of mice that developed toxoplasmosis after experimental infection by intraperitoneal inoculation of blood, amniotic liquid and cerebrospinal fluid from fetuses, newly born children and pregnant women with clinical and laboratory signals of toxoplasmosis. In all experiments where we detected the parasite in mice we also detected pathological lesions in the animal brains with great polymorphism between experiments. Edema was the most found lesion in all cases. Besides, it was possible to demonstrate the inflammatory process in 82.4% of cases and necrosis in 64.7% of cases, in agreement with the literature that describes severe neurological damage in its hosts.

Cysticercosis in the elderly.

The immunosenescence, a peculiarity of the aging process, increases the susceptibility of elderly individuals to neoplasia, infections, and parasitosis, among them, cysticercosis. The aim of this study was to compare the epidemiological and anatomopathological characteristics of cysticercosis in elderly or nonelderly patients. We reviewed 72 autopsies, protocols and specimens, performed in the School Hospital of the Triangulo Mineiro Federal University. We selected 3 groups: elderly with cysticercosis, nonelderly with cysticercosis, and control group without cysticercosis. From the patients with cysticercosis, 27.8% were elderly. Of these, 80% presented with neurocysticercosis and 20% cardiac cysticercosis. In the elderly, the early stages of the parasitic development, vesicular and colloidal vesicular, prevailed (75%). In relationship with the causes of death, death in 40% of the elderly was by neoplasic and 35% by cardiovascular, whereas for the nonelderly, death in 63.5% was by cardiovascular and 25% by infectious. There was a significant difference between groups with relation to neoplasic and cardiovascular causes. Therefore, cysticercosis was frequent in elderly patients, and probably patients are continuously infected with cysticercosis as they age. Perhaps, decurrence of the immunosenescence associated with immunological alterations caused by cysticercosis form favorable conditions to the development of neoplasias in the elderly attacked by the parasitosis.

Macroscopic aspects of chronic Chagas heart disease in aging.

OBJECTIVE: To describe the macroscopic characteristics of chronic Chagas heart disease in autopsied elderly. METHODS: The elderly studied were 60 or older. Twenty of them had chronic Chagas heart disease (CHD) and positive serology for the disease, and 14 had no heart disease (WHD) nor morphological changes suggestive of it and were serologically negative for Chagas disease. RESULTS: The CHD elderly had cardiac weight greater than the WHD (385 +/- 141.1 vs 306.8 +/- 62.1g, respectively; p > 0.05), in addition to significantly higher heart weight-to-body weight ratio (0.71% [0.5-1.42%] vs 0.59% [0.47-0.91%] p < 0.05). When compared, the CHD elderly presented lower fibrous thickening and/or atherosclerosis in the ascending aorta, mitral and tricuspid valves, and left and right coronaries than the WHD elderly. In the aortic and mitral valves, the lesions were significantly less severe (p < 0.05). Left ventricular apical lesion was observed in 45% of the CHD elderly, and intracardiac thrombosis in the left ventricle was found in 10% of them. CONCLUSION: Fibrous thickening and/or atherosclerosis were found to be less severe in the valves and arteries of the CHD elderly. Moreover, heart weight and intracardiac thrombosis frequency were lower than those detailed in the literature for non-elderly individuals.

Taenia crassiceps organic acids detected in cysticerci.

Taenia crassiceps cysticerci is used as an experimental model to cysticercosis studies; however there are subcutaneous cases of cysticercosis caused by these cysticerci. It remains unclear in the literature the energetic and fatty acid metabolism in cestodes. Its metabolic study may provide knowledge of pathways that may serve as potential anti-helminthic drugs sites of action. In this work we studied the citric acid cycle organic acids and the fatty acid oxidation in cysticerci removed from mice with 21 and 42 days of infection in two different evolutive stages: growing and final. The organic acids were extracted using perchloric acid and analyzed by HPLC methodology. We found significant statistically differences in oxalate, malate, lactate, and beta-hydroxybutirate concentrations between cysticerci. These results indicate the aerobic metabolism in vivo in spite of the low oxygen concentration of its habitat, and also indicate the presence of fatty acid oxidation as an alternative energetic source.

Experimental lagochilascariosis: histopathological study of inflammatory response to larval migration in the Murine model.

The goal of this study was to investigate the pattern of inflammatory response induced by Lagochilascaris minor in murine experimental model. For this purpose 115 mice were given 1000-3000 L. minor infective eggs "per os" and 51 uninfected mice were considered as controls. Four hours post-inoculation (PI), 3rd stage larvae were seen passing through the mucosa of terminal ends of small intestine. Six hours PI larvae were observed as an embolus inside the portal vein and also migrating through the liver parenchyma. During the first 24 h larvae-containing eggs of L. minor were observed in the lumen of intestinal tract. Two days PI larvae were seen migrating through lung parenchyma associated with an initial neutrophilic perivasculitis. From the 13th day of this experimental study, L. minor larvae were found mainly in skeletal muscles, in the center of granulomas. Concentric fibrosis with mixed inflammatory infiltrate involved the larvae after the 47th day PI, persistently. This experimental murine study with L. minor indicated that the 3rd stage larvae penetrated via ileum-cecal mucosa reaching the liver and probably other tissues through the hematogenic via. Throughout its pathway the larvae induced a granulomatous reaction, with abundant polimorphonuclear cells.