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A Grosso

Publications and source records attributed to A Grosso.

47 records · Page 3Linked to original sources

Patterns of membrane organization in toad bladder epithelium: a freeze-fracture study.

Two cell-types of toad bladder epithelium show uncommon plasma membrane organization in freeze-fractured specimens. One type, the granular cell, contains a plasma membrane in which the A-face is poorly particulate luminally while the B-face discloses multiple large particles at this site. In contrast, the lateral and basal portions of the granular-cell membrane are typical in that more particles occupy the A-face than the B-face. In the other cell-type, which is mitochondria-rich, the plasma membrane, luminally, laterally, and basally, contains rod-shaped and a few globular particles in the A-face. We suggest that these two peculiar membrane organizations be considered in the localization of both vasopressin and aldosterone action in toad bladder.

Animals↗

The hydrosmotic effect of vasopressin: a scanning electrom-microscope study.

Scanning electron-microscopy (SEM) was used to investigate the hydrosmotic effect of vasopressin on the apical surface of urinary bladders of toads Bufo marinus. Bladders were mounted on glass chambers and water fluxes were monitored with an optical method. Tissues were fixed in 2% glutaraldehyde and processed for SEM. Three types of cells were seen on the surface of control bladders:large polygonal (granular) cells, with blunt microvilli; smaller (mitochondria-rich) cells, with longer microvilli; goblet cells. Neither exposure of the bladders to a large osmotic gradient nor exposure to vasopressin in the absence of a gradient altered appreciably the epithelial surface. In contrast, the combination of vasopressin and an osmotic gradient resulted ina conspicuous diminution of the blunt microvilli. However, the small cells with longer microvilli remained unchanged. Identical results were seen with cAMP or theophylline in the presence of an osmotic gradient. These findings suggest that the hydrosmotic effect of vasopressin is mainly exerted on the granular cells of toad bladder and confirm observations made by others with the electron-microscope.

Animals↗

[Laparoscopic cholecystectomy. Our experience].

BACKGROUND: The many advantages and extreme versatility made laparoscopic cholecystectomy (L.C.) the gold standard for symptomatic cholelithiasis. The aim of this research is a retrospective analysis of personal experience with laparoscopic cholecystectomy in a peripheral hospital compared with the literature on the subject. METHODS: Since June 1982, a total of 989 L.C. have been performed. The patients were: 691 (68.6%) women and 298 (29.4%) men with a mean age of 56 years (range 17-84). The indications were: 791 symptomatic cholelithiasis, 142 chronic cholecystitis, 45 empyema-hydrops and 11 adenomyomatosis. RESULTS: No postoperative death have been observed and the conversion rate was of 24 cases (2.3%). The main complications were 3 cases of injury of the biliary tract and 2 cases of postoperative bleeding (1 from cystic artery and 1 from the umbilical wound). Minor complications observed were 12 cases (1.2%) of infections of the umbilical wound and 3 cases of umbilical hernia (0.3%). The elevation of stasis index was observed in 3 cases which solved spontaneously. The length of stay was 2 days in 957 cases (97%), 8 days in 24 cases and 4-5 days in 8 (0.7%). CONCLUSIONS: No major trochar's lesions occurred, contrary to the percentages quoted in the literature (0.02%-0.9%). The selective use of the open technique and of the multiuse conic section trocar in the "closed" technique is suggested. The 3 cases of bile duct lesions did not occur during the training period, contrary to what quoted in the literature. In personal opinion, a careful surgical technique with a good Calot's triangle preparation, is necessary to prevent these inconveniences. Parietal complications (umbilical wound infections and laparocele) even if lesser than in the laparotomy technique, can be reduced by using the endobag and suturing the abdominal fascia of the 10 mm trocars. Moreover, the use of a systematic subhepatic drainage during the first 24 postoperative hours is suggested, since it can be useful to reveal possible bleeding.

Adolescent↗