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991.
992.
Ferraz AA Leão CS Campos JM Coelho AR Zilbestein B Ferraz EM 《Arquivos de gastroenterologia》2007,44(2):162-167
BACKGROUND: Surgical options for morbid obesity are diverse, and the Roux-en-Y gastric bypass, initially described by Fobi has gained popularity. Knowledge about the physiology of the bypassed stomach is limited because this newly produced segment of the stomach is inaccessible to endoscopic or contrast radiological studies. AIM: To evaluate the myoelectric activity of the bypassed stomach and its reply to the feeding. METHODS: An experimental protocol was conducted to evaluate postoperative gastric bypassed motility in dogs submitted to the Roux-en-Y gastric bypass procedure. Two groups of five animals were studied on postoperative fasting and after a standard meal, recording electrical response and control activity. Both control and Roux-en-Y gastric bypass operated study group had a pair of electrodes placed on three points of the remaining stomach: fundus, body and antrum. Data registration was performed after complete ileus resolution, and analysed with DATA Q Inst. series 200. RESULTS: The results achieved on the conditions of this study suggest that: 1. the remaining stomach maintain the same pattern of motility; 2. there is a reduced fasting electromyography activity following the Roux-en-Y gastric bypass procedure; 3. significantly reduced fasting electric control activity when compared both groups, and a markedly reduced fasting response electric activity and; 4. the electric response to the feeding kept the same standard of the stomach, however in a statistically reduced way. CONCLUSION: The electrical activity of the bypassed stomach of Roux-en-Y gastric bypass procedure kept the same pattern but in a statistically reduced number of contraction. 相似文献
993.
BACKGROUND: The epidemiologic survey in Brazil is limited probably due to a diagnosis deficiency and a small number of population-based studies performed. The majority of the prevalence studies available have evaluated inflammatory bowel diseases outpatients, but the knowledge of the profile of inflammatory bowel diseases inpatients is important in order to detect predictive markers of disease severity that will allow earlier medical intervention decreasing the rate of hospitalization and reducing the Health System costs. AIM: To determine social, clinical, laboratorial and anthropometric profiles of hospitalized adults inflammatory bowel diseases patients of a tertiary university hospital. METHODS: Prospective study was performed with 43 inflammatory bowel diseases inpatients from clinical and surgical wards and emergency section of university hospital. We characterized demographic data, presence of comorbidities, disease location and behavior, surgical past-history, extra intestinal manifestations using standardized definitions. Laboratory results were abstracted from medical records and anthropometric measures were performed during our visit. RESULTS: The vast majority of the inflammatory bowel diseases patients had Crohn's disease (72.1%), with ileocolic involvement (60%), with a penetrating disease behavior (77.4%) while ulcerative colitis group presented mostly pancolitis (50%). Articular pain was the most common (44.2%) extra intestinal manifestation of inflammatory bowel diseases patients and 97.7% of them had at least one type of complication related to disease. Although, the previous use of specific medical therapies to inflammatory bowel diseases before the hospitalization (more frequently corticosteroids) was done (79%), the majority of the patients were hospitalized because of inflammatory bowel diseases activity. Disease activity was present in 80.7% of Crohn's disease and 50% ulcerative colitis patients. Inflammatory bowel diseases mortality rate was 5.5% (2/36). Comorbidities presence occurred only in 30.2% of inflammatory bowel diseases patients. The predominant surgery performed was intestinal resection. The interval between the symptoms appearance and the definitive diagnosis was less than 1 year in more than 70% of inflammatory bowel diseases patients. Laboratory findings detected were a decreased serum albumin (85.7%) and anemia (69.8%). The majority of the patients had at least one anthropometric alteration. The social stratification of the inflammatory bowel diseases group was similar to the Brazilian population. CONCLUSION: The inflammatory bowel diseases inpatients from the university hospital wards had more severe evolution of these illnesses with an active and extensive disease with complications and frequent extra intestinal manifestations, despite the prolonged use of corticosteroids. The higher prevalence of Crohn's disease inpatients than ulcerative colitis could reflect a higher aggressive behavior of this disease. The reduced serum albumin, anemia and anthropometric alterations are common inflammatory bowel diseases inpatients and could be related to a major severity of inflammatory bowel diseases evolution. 相似文献
994.
995.
Coutinho EM Silva FL Barros AF Araújo RE Oliveira SA Luna CF Barbosa AA Andrade ZA 《Acta tropica》2007,101(1):15-24
The mouse model of schistosomal periportal fibrosis (Symmers' "pipestem" fibrosis), that develops in 30-50% of the infected animals, is not reproduced in undernourished mice. Host nutritional status is likely to be a variable that may influence the outcome and progression of infection, since it interferes with the dynamics of connective tissue changes occurring in chronic hepatic schistosomiasis. Re-infections increase the occurrence of periportal liver fibrosis in well-nourished animals, but it is not known how undernourished mice would behave being repeatedly re-infected. So, 21-day-old male albino Swiss mice were individually exposed to 30 cercariae (percutaneous route) of the BH strain of Schistosoma mansoni, 4 weeks after being on a low-protein diet. Control animals were fed on a commercial balanced chow for mice. The nutritional status was evaluated by body weight gain and measurement of food intake. Mice were divided into four groups: A1 (undernourished, single infected), A2 (well-nourished, single infected), B1 (undernourished, re-infected), B2 (well-nourished, re-infected). The primary infection was performed 4 weeks after ingesting the respective diet. Re-infections started 45 days later, with exposure to 15 cercariae, at 15 day intervals. Mice were sacrificed 18 weeks after the primary exposure. The livers were submitted to morphological (gross and microscopic pathology), morphometric (percentage of fibrosis; granuloma size; volume and numerical densities) by using semi-automatic morphometry, and biochemical (quantification of collagen as hydroxyproline) studies. Worm burdens and hepatic egg counting were also recorded. Values for body weight gains were always lower in undernourished mice, the effects of re-infection being minimal on this regard. Liver and spleen weights were higher in well-nourished mice (either single infected or re-infected) and mainly related to the type of ingested diet. A greater number of re-infected well-nourished mice developed periportal fibrosis, but undernourished re-infected animals did not reproduce this lesion. The percentage of fibrosis and hepatic collagen content were higher in well-nourished mice, but differences between single infected and re-infected groups were not statistically significant. 相似文献
996.
Rossato LB Nunes AC Pereira ML de Souza CF Dummer C Milani V Porsch DB de Mattos CB Barros EJ 《Renal failure》2008,30(1):9-14
BACKGROUND: Damage to mitochondrial DNA (mtDNA) has been described in patients with chronic kidney disease (CKD). The presence of mtDNA 4977bp deletion in many different tissues can serve as a marker of this damage. However, no attempt has been made to detect the presence of mtDNA 4977bp in blood cells of patients with CKD. METHODS: Polymerase chain reaction techniques (PCR) were used to detect mtDNA 4977bp deletion in blood samples of 94 CKD patients. RESULTS: The prevalence of 4977bp deletion in mtDNA was 73.1% (38/52) in patients with CKD undergoing hemodialysis, 57.1% (27/42) in patients with CKD receiving conservative treatment, and 27.8% (15/54) in control samples (p < 0.001). Higher prevalence of this mutation was not associated with patient age (p = 0.54) or time on hemodialysis (p = 0.70). CONCLUSION: The higher prevalence of mtDNA 4977bp deletion in patients in this study indicates that the CKD can induce damage to mtDNA in blood cells and could be exacerbated by hemodialysis. 相似文献
997.
Savassi-Rocha AL Diniz MT Savassi-Rocha PR Ferreira JT Rodrigues de Almeida Sanches S Diniz Mde F Gomes de Barros H Fonseca IK 《Obesity surgery》2008,18(11):1364-1368
Background Capella surgery is one of the technical variations of Roux-en-Y gastric bypass. The method includes the preparation of an
alimentary (Roux) limb with a standardized length (110 cm) in order to induce deficiencies in the absorption of macronutrients
and thereby contribute to weight loss. The recognized variation in jejunoileal length in humans (approximately 4 to 9 m) is
not considered, although this range correlates with the wide variation in the length of the common limb.
Methods In order to assess the influence of variations in jejunoileal and common limb lengths on weight loss, intra-operative measurements
were made of these segments on 100 patients undergoing Capella surgery. Patients were followed for a period of 1 year. Statistical
analysis included subdivisions of the population by gender and body mass index.
Results Average jejunoileal length was 671.4 ± 115.7 cm (434–990 cm). Average common limb length was 505.3 ± 113.3 cm (268–829 cm).
No correlation was detected between jejunoileal length and weight loss at 6 months or 1 year following surgery. A weak negative
correlation was detected between weight loss and common limb length at 1 year following surgery in male and super-obese patients.
Conclusions Jejunoileal and common limb length vary widely in gastric bypass patients. To make modifications in the alimentary and/or
biliopancreatic limb length, surgeons must consider the variability of the jejunoileal and common limb length. 相似文献
998.
Karine J. Sarro Amanda P. Silvatti Ricardo M. L. Barros 《Journal of Sports Science and Medicine》2008,7(2):195-200
This work aimed to verify if swimmers present better chest wall coordination during breathing than healthy non-athletes analyzing the correlation between ribs motion and the variation of thoracoabdominal volumes. The results of two up-to-date methods based on videogrammetry were correlated in this study. The first one measured the volumes of 4 separate compartments of the chest wall (superior thorax, inferior thorax, superior abdomen and inferior abdomen) as a function of time. The second calculated the rotation angle of the 2nd to the 10th ribs around the quasi-transversal axis also in function of time. The chest wall was represented by 53 markers, attached to the ribs, vertebrae, thorax and abdomen of 15 male swimmers and of 15 non- athletes. A kinematical analysis system equipped with 6 digital video cameras (60Hz) was used to obtain the 3D coordinates of the markers. Correlating the curves of ribs rotation angles with the curves of the separate volumes, swimmers presented higher values than non-athletes when the superior and inferior abdomen were considered and the highest correlation values were found in swimmers for the inferior thorax. These results suggest a better coordination between ribs motion and thoracoabdominal volumes in swimmers, indicating the prevalent and coordinated action of the diaphragm and abdominal muscles to inflate and deflate the chest wall. The results further suggest that swimming practice leads to the formation of an optimized breathing pattern and can partially explain the higher lung volumes found in these athletes reported in literature.
Key points
- The study revealed that swimmers present higher correlation between the ribs motion and the variation of abdominal volumes than non-swimmers, suggesting that swimming practice might lead to the formation of an optimized breathing pattern, increasing the coordination between the thoracoabdominal volumes and the ribs motion.
- No previous work was found in the literature reporting this optimized breathing pattern in swimmers.
- The higher coordination between the thoracoabdominal volumes and the ribs motion found in swimmers can partially explain the higher lung volumes reported in literature for these athletes.
999.
Barros M Giorgetti M Souto AA Vilela G Santos K Boas NV Tomaz C 《Pharmacology, biochemistry, and behavior》2007,86(4):705-711
Initial investigations indicated the use of the Marmoset Predator Confrontation Test (MPCT) as an experimental procedure to measure fear/anxiety-related behaviors in non-human primates. However, possible long-term habituation effects and re-use of experimental subjects need to be verified. This study, therefore, compared the behavioral response of experienced versus na?ve adult black tufted-ear marmosets (Callithrix penicillata) in the MPCT, with/without diazepam administrations. Subjects were tested in the figure-8 maze and confronted with a taxidermized wild-cat predator stimulus. After four initial 20-min maze habituation sessions, each subject was submitted to two randomly-assigned 20-min predator confrontation sessions: vehicle and 2 mg/kg of diazepam. Confrontation with the predator induced significant behavioral changes; i.e., proximic avoidance and tsik-tsik alarm call. Diazepam administration, concomitant to predator exposure, reversed the behavioral changes observed. In both the experienced and na?ve marmosets a similar behavioral profile and response pattern to diazepam was detected, corroborating the important selective pressure that felines seem to have on marmoset behavioral ecology. Therefore, during a more naturalistic-like regimen--i.e., recurring intermittent predator encounters--the general response pattern remains highly consistent, regardless of prior experience. One may consider the re-use of marmoset subjects in the MPCT, particularly under these specific conditions (i.e. repeated 20-min confrontations, 72-h apart). 相似文献
1000.