Transmission electron microscopic investigation of the dark and light pancreatic acinar beta-cells of young-domesticated pig (Sus Suidae, Erxleben 1777).

BACKGROUND: The current study was designed to perform a transmission electron microscopic investigation focusing on the dark and light pancreatic acinar ß-cells of young domesticated pig (Sus Suidae). MATERIALS AND METHODS: This study depended on the fresh pancreatic specimens from 5 healthy young (2-month-old) pigs that were collected immediately after they were slaughtered at the abattoir of Abdelkader Alexandria, Egypt. RESULTS AND CONCLUSIONS: In our findings, the acinar pancreas was formed of pyramidal pancreatic acinar cells with large spherical nuclei of condensed heterochromatin at the periphery and prominent eccentric nucleoli. Zymogen granules were observed at the apical region of the acinar cells, and they appear as electron dense bodies. Numerous mitochondria and Golgi complexes observed in the acinar cell cytoplasm. The electron dense acinar cells were joined by junctional complexes. The rough endoplasmic reticulum was more prominent in the electron-dense acinar cells than did electron-lucent acinar cells. There was no connective tissue capsule separate the acinar portion of pancreas from the pancreatic islets. The pancreatic islets mainly formed of ß-cells. The irregular α-cells possess numerous small granules. The cytoplasmic ß-cells granules were surrounded by hallow area and enclosed by a limiting membrane. Delta cells were generally polygonal in shape and found in clumps throughout the islet and they were also identified in between ß-cells. Their granules were of moderate electron density and were generally smaller than ß-cells' granules. The limiting membrane was tightly enclosed the delta cells granules and the hallow area around the granule were found similar to the granules of ß-cells.

Ultrastructural investigation of the pneumocytes in piglets that live in a trashed environment.

The present study provides the ultrastructure of the pneumocytes types II and I in piglets living in the trash environment. Samples of the lungs of twelve piglets two months old were used. By light microscopy, the pneumocytes type I were squamous and somewhat flattened cells, while pneumocytes type II was cuboidal to spherical projected within the alveolar lumen and characterized by a spherical nucleus and foamy cytoplasm, it contained vacuolated bodies that were polygonal with variable size manly at the poles of the cell. The electron microscopy investigation showed blood air barrier between the endothelial lining of pneumocytes type I and therefore the endothelial lining of blood capillary and their nucleus were irregular in shape varied from nearly irregular triangular to polygon rough endoplasmic reticulum represented at their cytoplasm. The pneumocytes type II were frequently covered by pneumocytes type I extensions and united to them by a tight junction. It had been characterized by a high number of mitochondria within the cytoplasm and vacuolated bodies encircled the nucleus and at the two extremities of the cell. The lamellar vacuolated bodies were connected to the endoplasmic reticulum membranes and therefore the intravascular macrophages were attached to the endothelial cells within the pulmonary capillaries until two months old piglets. The occurrence of the intravascular macrophages could be attributed to the higher resistance to the respiratory diseases of the piglets.

Antimicrobial susceptibility of non-penicillinase and penicillinase-producing Neisseria gonorrhoeae strains isolated in Tripoli, Libya.

Neisseria gonorrhoeae culture gave a positive result in 42 of 64 male adults with purulent urethral discharge. The majority of the infections were acquired outside Libya. Twenty-seven strains (64.3%) were non-penicillinase producing (NPPNG) and 15 (35.7%) were penicillinase producing (PPNG) by starch paper technique. Antimicrobial susceptibility of the strains to 5 antibiotics was carried out by agar-plate dilution technique. Twenty-three NPPNG strains (54.8%) were susceptible to penicillin with a minimum inhibitory concentration (MIC) of less than or equal to 0.5 micrograms/ml. In 4 strains (9.5%), a high resistance to penicillin (MIC greater than or equal to 16 micrograms/ml) appeared to be chromosomally-mediated (CMRNG). All PPNG strains were resistant to penicillin (MIC greater than or equal to 1 microgram/ml). While resistance to erythromycin (MIC greater than or equal to 1 microgram/ml) and tetracycline (MIC greater than or equal to 1 microgram/ml) was observed in 5 strains, resistance to kanamycin (MIC 32 micrograms/ml) and spectinomycin (MIC 64 micrograms/ml) was present in only one strain. Whereas no significant differences were recorded in MICs of erythromycin, tetracycline, kanamycin and spectinomycin between NPPNG and PPNG strains, one PPNG strain was found to be resistant in vitro to all 5 antibiotics.

Primary and acquired drug resistance in Mycobacterium tuberculosis strains in western region of Libyan Arab Jamahiriya.

Drug resistance in Mycobacterium tuberculosis strains prevalent in the Western Region of Libyan Arab Jamahiriya was studied for the years 1984, 1985 and 1986 at the regional tuberculosis control centre at Gurgi, Tripoli. Records of resistance to streptomycin, isoniazid, ethambutol and rifampicin were analysed. Whereas primary drug resistance was observed in 5.1%, 19.5% and 3.8%, acquired drug resistance was found in 12.2%, 34.0% and 15.3% of the strains in 1984, 1985 and 1986 respectively. Only 3 out of 598 strains (1.2%) were found to show acquired resistance to rifampicin. No primary resistance to rifampicin was observed. The situation of drug resistance in pulmonary tuberculosis in the Jamahiriya is discussed.