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Biomedical subjects

M Ando

Publications and source records attributed to M Ando.

At least 1,153 records · Page 64Linked to original sources

Effect of nicotine on gastric acid secretion: evidence of electrogenic pump theory.

In vitro studies on H+ secretion, potential difference (PD), short-circuit current (Isc), and resistance across stripped mucosa of frog stomach in Cl-medium have shown that addition of nicotine in the serum bathing fluid caused a marked inhibition of the H+ secretory rate and an increase of PD and Isc without change of the transmucosal resistance. A dose-response correlation was indicated. During the first 8 min, the changes in the measured parameters, namely, PD versus Ih and Isc versus Ih, were linear. After 8 min, a deviation from linearity was observed. From the slope of the regression lines, the resistance of the electrogenic Cl- pump on the mucosal membrane (Rcl) was calculated to be 127 omega cm2 and the resistance of the chloride pathway on the serosal side (Rcl) was 407 omega cm2. The resistance of the H+ pump on the mucosal membrane (Rh) in Cl- medium was estimated to be 385 omega cm2. The sum of the emf's of the Cl+ pump on the mucosal membrane and of the Cl- gradient across the serosal membrane, namely Ecl + Ecl, was found to be 35 mV. The presence of such linear relationships between measured versus the H+ rate and Isc versus Ih lends support to the electrogenic theory of HCl secretion.

Animals↗

Histochemical studies relating the activation of macrophages to the intracellular destruction of tubercle bacilli.

Dermal tuberculous lesions, both primary and those of reinfection, were produced in rabbits with 14C-labeled BCG and biopsied once at various times. Macrophage activation was evaluated by the indolyl histochemical test for beta-galatosidase, the number of bacilli in macrophages by acid-fast staining, and the breakdown of bacilli by autoradiography. After the rabbits became tuberculin positive, the stongly activated macrophage population contained a) fewer parasitized cell, b) fewer bacilli in each parasitized cell, and c) more "free" 14C-label (not associated with intact bacilli) than the weakly activated macrophage population. These results suggest that the more highly activated macrophages had destroyed many of the bacilli that they once contained and that their power to do so was enhanced by immunologic mechanisms.

Animals↗

Total anomalous pulmonary venous connection: Report of 93 autopsied cases with emphasis on diagnostic and surgical considerations.

Total anomalous pulmonary venous connection (TAPVC) is failure of development of the common pulmonary vein, with consequent ersistence and enlargement of embryonic collaterals between the lungs and the systemic veins. In the great majority (91 of 93 autopsied cases, 97 per cent, no remnant of the common pulmonary vein was found, supporting the concept of agenesis or involution of the common pulmonary vein. Occasionally, a cordlike strand was found in the location of the common pulmonary vein (in three of 93 cases, 3 per cent), supporting the concept of atresia of the common pulmonry vein. The order of frequency of the various types of TAPVC was: left innominate vein ("snowman"), 26 perent cent; subdiaphragmatic, 24 per cent; coronary sinus, 18 per cent; right superior vena cava, 15 per cent; right atrium, 8 percent; mixed, 5 per cent; azygos, 2 per cent; and left supeior vena cava, 2 per cent...

Adolescent↗

Different effects of phytohemagglutinin-activated lymphocytes and their culture supernatants on macrophage function.

When rabbit peritoneal exudate cells were incubated for 24 and 48 h with phytohemagglutinin-activated lymphocytes or their culture supernatants, two times as many cells remained adherent to culture slides as in the controls. More spreading cells were found among the adherent cells in the stimulated cultures. Eighty percent of spreading cells that were induced by supernatants were negative or faintly positive for beta-galactosidase. On the other hand, half of the spreading cells induced by activated lymphocytes were positive (1+ to 4+) for beta-lymphocytes and their supernatants. Under similar conditions, unstimulated peritoneal cells showed less marked activation. These findings show that macrophages can appear morphologically activated and yet not be enzymatically activated by lymphokines. Possible mechanisms of direct interaction of activated lymphocytes and macrophages are discussed.

Animals↗

Turnover of tritiated-thymidine-labeled mononuclear cells in tuberculous lesions of rabbits: a comparison of primary dermal BCG lesions and those of reinfection.

Rabbits were infected or reinfected intradermally in multiple sites with BCG. One day before the BCG infection they were injected iv with a single pulse of tritiated thymidine (3HT). At various times thereafter, the BCG lesions were biopsied and evaluated for 3HT-labeled mononuclear cells (MN), which are mostly macrophages but include some lymphocytes. Periodically Old Tuberculin (OT) was infected intradermally, creating MN traps, which were biopsied and evaluated 1 day after their onset. These traps monitor the population of 3HT-labeled MN in the blood stream that readily enters sites of inflammation. During the first 5 days after the 3HT pulse, a higher percentage of labeled MN accumulated in tuberculin traps on rabbits reinfected with BCG than in traps on rabbits with primary infection. The high percentage of labeled MN in the former was probably due to the more intense inflammation cuased by preexisting tuberculin hypersensitivity. By 8 days after the 3HT pulse, a lower percentage of labeled MN had accumulated in BCG lesions of reinfection than in primary BCG lesions. Evidently the presence of delayed hypersensitivity increased the turnover of MN in tuberculous lesions. By 15 days after the 3HT pulse, the percentage of 3HT-labeled MN was much higher in BCG lesions than in 1-day traps, suggesting that such MN had accumulated in the lesions over a period of several days.

Animals↗