Mast cells and synaptic transmission in sympathetic ganglia.
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Animals↗
Biomedical subjects
J Roa
Publications and source records attributed to J Roa.
Effect of progesterone on acrosome reaction, hypoosmotic swelling test, and DNA stability in human spermatozoa.
The association between different sperm parameters, an in vitro effect of progesterone, has not been studied satisfactorily. In this article, the effect of progesterone on acrosome reaction (AR), plasma membrane integrity, and chromatin stability has been assessed in human spermatozoa with normal morphology and motility. Semen samples were obtained by masturbation from 25 patients. Two criteria of classification were utilized in this study: high motility group and normal morphology group incubated with progesterone. The effect of progesterone on AR, plasma membrane integrity, and chromatin stability in human spermatozoa with normal morphology and motility was realized. The results suggest that only the subpopulation of spermatozoa with normal morphology is able to undergo the progesterone-induced AR. It is possible that in the reproductive female tract it takes place a high selection of sperm with chromatin stability determined and optimal plasma membrane to undergo the AR prerequisite for the fecundation.
Acrosome Reaction↗
Arm training reduces the VO2 and VE cost of unsupported arm exercise and elevation in chronic obstructive pulmonary disease.
BACKGROUND: Patients with severe chronic obstructive pulmonary disease (COPD) may develop dyspnea with minimal arm activity, thoracoabdominal dyssynchrony with unsupported arm exercise (UAEX) and increased oxygen uptake (VO2), and minute ventilation (VE) with simple unsupported arm elevation (UAE) and UAEX. We investigated whether unsupported arm training, as the only form of exercise, could decrease the VO2 and VE cost (percentage increase from resting baseline) associated with unsupported arm elevation and exercise, respectively. METHODS: Twenty-six patients with severe COPD were randomized to 21-24 sessions of unsupported arm (ARMT) or low-intensity resistive breathing (RBT) training as the only form of exercise. Patients were studied before and after training using a metabolic cart and esophageal and gastric pressures to evaluate metabolic and respiratory muscle function. RESULTS: After ARMT, the VO2 (58% vs 38% increase, P < 0.05) and VE (41% v. 21% increase, P < 0.05) cost for UAEX at exercise isotime decreased and endurance time increased. Similarly the VO2 (25% vs 18% increase, P < 0.05) cost decreased and VE no longer increased in response to 2 minutes of UAE after ARMT. The RBT group showed no such change. No improvement in ventilatory load or respiratory muscle function could be identified to explain the physiologic changes observed. After ARMT, mean inspiratory flow (VT/TL), a measure of central respiratory drive, was reduced during UAEX and the expected increase during UAE did not occur. CONCLUSION: We conclude that arm training reduces the VO2 and VE cost of UAE and UAEX, possibly through improved synchronization and coordination of accessory muscle action during unsupported arm activity.
Aged↗
Gallbladder cancer in a high risk area: morphological features and spread patterns.
BACKGROUND/AIMS: Gallbladder carcinoma is one of the most frequent malignant tumors in Chile. The aim of this paper is to show our experiences in gallbladder carcinoma. METHODOLOGY: Six-hundred-sixty-nine cases of gallbladder carcinoma were included in this prospective study; 557 females (83.5%) and 112 males (16.5%). In 466 cases (70%), diagnosis was carried out in the cholecystectomy sample, 45 cases were partial cholecystectomies and 158 cases were metastases of gallbladder carcinoma. RESULTS: Ninety-eight per cent of the cases were adenocarcinomas, and in 85% of the cases gallstones were observed. Thirty-seven per cent of the primary tumors were macroscopically inapparent. One-hundred-thirty-one cases (29%) were early carcinomas and 323 cases (71%) were advanced carcinomas. A relationship between differentiation grade and infiltration level (p=0.0001) was observed. Lymph-node metastasis was found in 18.5%, 4.5% and 3.3% in the first, second and third lymph-node barriers respectively. Muscular tumors presented no lymph-node metastasis, while in serosal tumors lymph node metastasis reached 62% (p=0.04). Hepatic tumor infiltration was observed in 11%, 19% and 38% of muscular, subserosal and serosal tumors. CONCLUSIONS: The high frequency of inapparent carcinomas, gallstones and inflammatory changes of the vesicular wall are elements that make the pre-operative diagnosis of gallbladder carcinoma difficult. Differentiation grade and infiltration level are the most reliable prognostic factors in gallbladder carcinoma. Lymph-node metastasis or liver tumor infiltration are infrequent in early gallbladder carcinoma.
Adenocarcinoma↗