Cell types of the pars distalis of the hedgehog (Erinaceus europaeus L.) adenohypophysis: cytological, immunocytochemical and ultrastructural studies. 4. Thyrotropic cells

Staining and histochemical methods, immunofluorescence and electron microscopy were used to individualize the thyrotropic cells in the adenohypophysis of the non-hibernating hedgehog. One cell type was differentiated; its characteristics at the light and electron-microscopic levels were presented. Immunofluorescence has confirmed the functional significance of this cell type and the validity of the denomination of 'thyrotropic cells'.     

Ultrastructure of the ventricular myocardium of the bat Eidolon helvum

Ultrastructural studies, including a preliminary morphometric analysis, of the right ventricular myocardium in the West African bat Eidolon helvum show that the myocytes contain a wider T-tubule system and a higher proportion of mitochondria and lipid droplets than in typical terrestrial mammals such as the rat; these features in the bat are even mor pronounced than in hibernating species such as the golden hamster. In addition to having coupling arrangements with T-tubules and surface sarcolemma, cisterns of junctional sarcoplasmic reticulum are closely apposed to mitochondria and lipid droplets.     

Hansen's disease (leprosy). Diagnosis by aspiration biopsy of lymph nodes

A 61-year-old male native of Mexico presented with generalized enlargement of lymph nodes. Fine needle aspiration (FNA) biopsy established lepromatous leprosy as the cause of the lymphadenopathy. The cytologic findings included abundant, frequently multinucleated histiocytes (globus cells), the cytoplasm of which showed multiple vacuoles; cytoplasmic membrane-bound vacuoles were seen free in the background. The vacuoles contained large numbers of acid-fast bacilli. Globus cells, while characteristic, are not specific for Mycobacterium leprae infection and are seen in certain atypical mycobacterioses in immunodeficient patients. This appears to be the first report of lymphadenopathy due to lepromatous leprosy in which the diagnosis was made by FNA biopsy. The immunologic spectrum of leprosy is correlated with clinical and pathologic findings, and the need to remember infectious processes in evaluating lymphadenopathy and the value of reserving air-dried and alcohol-fixed smears for special stains are emphasized.     

The relationship between maternal age and chromosome size in autosomal trisomy.

The pattern of maternal age-specific incidence of autosomal trisomy in spontaneous abortions was examined for each chromosome for which a sufficient number of trisomies was observed. This included chromosomes 2, 4, 7-10, 13-16, 18, and 20-22. The rate of increase after age 30 for each of the small chromosomes (groups D-G) was similar, with the exception of chromosome 16, which showed a significantly shallower rate. The C group chromosomes tended to have an intermediate rate of increase after age 30, with the exception of chromosome 7, which had a pattern similar to the smaller chromosomes. The larger chromosomes (2 and 4) had the smallest rate of increase. There was a significant relationship between chromosome size and rate of increase after age 30 (after excluding chromosome 16), but not with rate of increase before age 30. The results suggest that autosomal trisomies may be of heterogeneous origin, with a maternal age-related factor associated with chromosome size and other sources unrelated to chromosome size. Additional evidence for and against this hypothesis is discussed.     

Variations in left and right ventricular oxygen balance produced by paired electrical stimulations

The possible differential effect of positive inotropic stimulation upon regional myocardial oxygen balance in the two ventricles was investigated during tachycardia and paired electrical stimulation. Isometric contractile force was measured by strain gauge arches; local coronary blood supply was measured by thermistor probes and intracellular NADH redox level was recorded using surface fluorometry. It was found that when contractility was increased by paired stimulation at a basic rate of 140 bpm, the inotropic response was more pronounced in the right ventricle (97.2 +/- 11.5%) than in the left (63.1 +/- 12.6%). Coronary blood supply to the left ventricle increased by 117.8 +/- 30.4% and the corresponding NADH redox level increased by 54.3 +/- 19.9%. When the contractile force was increased to the same extent (64.1 +/- 8.9%) by single stimulation at a rate of 210 bpm, the coronary flow to the left ventricle was increased by only 36.4 +/- 11.0% and the NADH state rose by 67.1 +/- 12.1%. It is concluded that paired stimulation reduced the mechanical limitation to flow during tachycardia, thus allowing coronary blood supply to increase in response to positive inotropic stimulation, thereby preserving a relatively improved oxygen state. It was also observed that the ratio contractile force/blood supply (contraction efficiency) was usually proportional to the NADH redox level (oxygen balance). Nevertheless, variations observed in the force/supply ratio for the left ventricle indicate that the NADH redox level cannot be predicted quantitatively by the force/supply ratio.     

Effect of calcitonin on the interdigestive motility and on gastric and pancreatic secretion in humans

Calcitonin given in doses (0.2 and 1 MRC U/kg-1h-1) reproducing the levels observed in medullary carcinoma of the thyroid, induced the appearance of phase III type activity and reduced the duration of the IMC in the small intestine from 123 to 87 min with 0.2 MRC U kg-1h-1 and from 123 to 43 min with 1 MRC U kg-1h-1 but not in the stomach of young volunteers. This increase in phase III-like activity occurred despite a sharp reduction in motilin levels. Only the highest dose of calcitonin reduced significantly acid secretion (by more than 90%) while both doses reduced amylase secretion by respectively 65 and 71% when compared to the control levels. These changes in motility and secretion could partly explain the diarrhea observed in patients with the medullary carcinoma of the thyroid.     

Cationic form of beta-galactosidase in the germinating seeds of Vigna sinensis (Linn) Savi

The cationic form of beta-galactosidase (EC 3.2.1.23) from the germinating seeds of Vigna sinensis has been separated from its other isoforms by DEAE-cellulose (DE-52) column chromatography and further purified by gel filtration and affinity chromatography. Polyacrylamide gel electrophoresis of the purified enzyme imparted a single protein band. The molecular mass of the enzyme as determined by Sephadex G-150 gel filtration is 58,800 Da. The optimum temperature and the optimum pH are 60 degrees C and 4.5, respectively. Most of the metal ions tested were inhibitory to the enzyme activity. The enzyme has Km for p-nitrophenyl beta-D-galactoside and o-nitrophenyl beta-D-galactoside of 0.56 and 2.0 mM, respectively. The Ki values of galactose and lactose are 2.4 and 70.0 mM, respectively. The energy of activation of PNPG for the enzyme is 10.3 kcal/mol.     

Induction of gametocytogenesis in Plasmodium falciparum by the culture supernatant of hybridoma cells producing anti-P. falciparum antibody

There have been many unsuccessful attempts to induce gametocytogenesis in vitro. In the present experiment, however, we found that RPMI-CS medium and RPMI-FS medium prepared by dissolving powdered RPMI 1640 medium in the culture supernatants of hybridoma cells, hybrid line D21 and 219.5, respectively, that produce anti-P. falciparum antibody induced gametocytogenesis. Gametocytogenesis was consistently observed from 3 days after addition of these media. The culture supernatant of anti-P. falciparum antibody producing hybridoma cells did not induce gametocytogenesis in the absence of RPMI 1640 medium. RPMI-MS medium, prepared by dissolving powdered RPMI 1640 medium in the culture supernatant of myeloma cells, SP2/O-Ag 14, which was used as a control, induced a few gametocytes.