RESUMEN
BACKGROUND: The aim of the study was to analyze the mechanism of deterioration of implanted arteries. METHODS: Eleven patients were included. Samples of vascular segments obtained from multiorgan donors and samples of the same vascular segments after explantation in the recipient were analyzed. Blood group, time of cold and warm ischemia, cause of death, time spent in the intensive care unit, time of storage of the cryopreserved grafts, and anatomopathological and immunohistochemical studies were analyzed using the preimplant samples obtained from the multiorgan donor. For samples obtained from the recipient, blood group, duration for which the tissue from the donor has been implanted, reason for graft explantation, and anatomopathological and immunohistochemical studies were analyzed. RESULTS: Histopathologically, the main finding has been the substitution of the muscular cap of the arterial wall by an intense fibrosis, in most of the cases, of a symmetrical nature. Besides this degeneration of myocytes, there is marked perivascular fibrosis and fibrointimal thickening also exists. The T lymphocytes suggest the importance of the immunological mechanism in the distortion of the architecture of the arteries. The atherosclerosis plays a less relevant role. CONCLUSIONS: Evidence of immune-mediated injury was found, and this mechanism seems to be responsible for the degenerative process in cryopreserved homografts.
Asunto(s)
Arterias/trasplante , Bioprótesis , Implantación de Prótesis Vascular/efectos adversos , Criopreservación , Rechazo de Injerto/etiología , Inmunohistoquímica , Linfocitos T/inmunología , Antígenos CD/análisis , Arterias/inmunología , Arterias/patología , Biomarcadores/análisis , Fibrosis , Rechazo de Injerto/inmunología , Rechazo de Injerto/patología , Humanos , Músculo Liso Vascular/inmunología , Músculo Liso Vascular/patología , Músculo Liso Vascular/trasplante , España , Factores de TiempoRESUMEN
Limbal stem cells (LSC) have an important role in the maintenance of the corneal surface epithelium, and autologous cultured limbal epithelial cell (HLECs) transplantations have contributed substantially to the treatment of the visually disabling condition known as LSC deficiency. A major challenge is the ability to identify LSC in vitro and in situ, and one of the major controversies in the field relates to reliable LSC markers. This study was carried out to evaluate the culture of a limbal biopsy on human amniotic membrane (HAM): directly on the chorionic side and on intact epithelium, and the expression of the stem cell associated markers: ABCG2, p63. HAM has been extensively used for ocular surface reconstruction and has properties which facilitate the growth of epithelial cells controlling inflammation and scarring.
Asunto(s)
Amnios , Limbo de la Córnea/citología , Limbo de la Córnea/crecimiento & desarrollo , Células Madre/citología , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Transportadoras de Casetes de Unión a ATP/biosíntesis , Técnicas de Cultivo de Célula , Córnea/citología , Células Epiteliales/citología , Células Epiteliales/metabolismo , Epitelio Corneal/citología , Epitelio Corneal/metabolismo , Células Nutrientes , Humanos , Limbo de la Córnea/metabolismo , Proteínas de la Membrana/biosíntesis , Proteínas de Neoplasias/biosíntesis , Células Madre/metabolismo , Técnicas de Cultivo de TejidosRESUMEN
A simple and inexpensive assay for detection of H2S producing bacteria in drinking water was evaluated in Paraguay. Using an improved preparation procedure, results were basically temperature independent in the range of 22-37ºc and correlated well with the presence of total coliform bacteria (96 percent, 28ºc). The assay was not suitable for control of surface water and dug well water due to the frequent presence of non-faecal coliforms. However, it was very suitable for routine control of high quality water-systems, like treated community water systems or deeep-tube well water, where complete absence of coliforms is required a laboratory technician or special equipament. Its use permits a cost-effective routine control of high quality community water systems in developing countries. In addition, this test turned out to be an effective educational tool for heightening the awareness of people towards dangers of unclean drinking water
Asunto(s)
Agua Potable , Cribado de LíquidosRESUMEN
The prevalence intestinal of parasitosis was studied in a population of 150 children, which ages ranged from one to fourteen years, from Guazú-Cuá department of Paraguarí, which is an isolated community with very poor sanitary conditions. Feces from all 150 children were examined by the concentration and the Willis methods, and 94 percent of them had parasites (62.7 percent), 74 had only one parasites (78.7 percent) and 20 had two or more parasites (21.3 percent). Giardia lamblia was the most frequent parasite (22.0 percent) followed by Uncinaria (5.3 percent). The most frequent combination was that of Giardia and Uncinaria (5.3 percent). No age or sex preference for the parasites was detected. The high infestation rate suggests the need of improvement of the sanitary conditions and the education of the population
Asunto(s)
Parasitosis Intestinales , ParaguayRESUMEN
The nutritional status of the children in the rural community of Guazu-Cuá, Paraguarí Department, Paraguay, was evaluated within the frame of a project on primary health care. The study was carried out twice (July 1989 and July 1990) in children of both sexs with ages from one month to ten years, using anthropometric parameters and derived indexes such as boby weight:age ratio, height:ages ratio, and boby weight:height ratio. From the 86 evaluated chlidren, 74.5 percent showed normal values, 11.5 percent display signs of a previous malnutrcicion, 2.5 percent actual malnutricion, and 11.5 pervcent were overweight. It is very interesting to emphasize that the percentages of malnourished and overweight children were similar in the two evaluations
Asunto(s)
Estado Nutricional , Nutrición del Lactante , Trastornos Nutricionales , Trastornos de la Nutrición del Niño , ParaguayRESUMEN
An epidemiological survey was preformed in 81 children forn a rural town, Escobar, in order to determine the prevalence of the intestinal parasitosis by four different methods. Out of the 81 samples studied, 63 yielded positive parasitosis (77.8 percent). The most frecuent parasites fuond were Blastocistis hominis (60.3 percent), uncynaria (46 percent) and Giardia lamblia (34.9 percent). In 40 samples, more than one parasite were detected. In 22,13 and 5 cases were found 2,3 and more parasites, respectively
Asunto(s)
Parasitosis Intestinales , Prevalencia , ParaguayRESUMEN
The prevalence of Trypanosoma cruzi infection was studied in a population of 158 children, which ages ranged from 4 months to thirteen years, from Guazú-Cuá department of Paraguarí, which is an isolated community within the endemic area for Chagas'disease. Twelve out of 158 ( 7.6 percent) children yielded positive results for the detection of anti-T. Cruzi antibodies by Elisa. Three cases (1.9 percent) were recorded in children under 5 years of age. These results reveal a high prevalence, according to the criteria establish by the WHO