Relaxation of imprinting of IGFII gene in juvenile nasopharyngeal angiofibromas.

IGFII and H19 genes are expressed only from one allele due to genomic imprinting, biallelic expression (loss of imprinting) being associated with the tumorigenic process of different types of tumors. The mechanism responsible for genomic imprinting is not yet determined, although DNA methylation has been considered the main genetic event for an imprinted mark. In the current study, the authors analyzed the imprinting status and expression levels of the IGFII and H19 genes in 27 cases of Juvenile Nasopharyngeal Angiofibroma (JNA) using RFLPs, RT-PCR, and Southern and Northern Blots. The authors found that four out of eight informative cases (50%) for ApaI/IFGII polymorphism showed biallelic expression of IFGII whereas none of the nine informative cases for the polymorphism showed biallelic expression of the H19 gene. Overexpression of IFGII was observed in 8 out of 22 cases (36.4%), and 7 out of 19 cases (36.8%) showed H19 overexpression. Hypomethylation was found only in the H19 gene in six out of eight cases analyzed. Therefore, our results demonstrate that alterations in the IFGII/H19 imprinted region occur in JNA.     

Comparative haematological and plasma chemistry values in purpose-bred squirrel, cynomolgus and rhesus monkeys

Haematological and blood chemistry data have been compared for three species of purpose-bred primates, Macaca mulatta (rhesus monkey), Macaca fascicularis (cynomolgus monkey), Saimiri sciureus (squirrel monkey). These species were housed over a 9-month period in identical conditions (diet, tap water, room temperature and relative humidity, and lighting regime) in our primate facility. Blood and urine assays were conducted using the same pre-analytical conditions (blood sampling procedure, anticoagulant and storage of sample), and analytical methods (reagent and equipment).The results indicated that squirrel, rhesus and cynomolgus monkeys have essentially biologically similar values for all of the parameters examined. However, haemoglobin level, reticulocyte, plasma total cholesterol, triglyceride, albumin and urea nitrogen values, and urinary osmolality in cynomolgus monkeys were statistically lower than those of rhesus monkeys. Erythrocyte count, plasma ALT, calcium and potassium in cynomolgus monkeys were statistically higher than those of rhesus monkeys. Erythrocyte count, haemoglobin level, haematocrit, reticulocyte, plasma total bilirubin and chloride and urinary osmolality in cynomolgus monkeys were statistically lower than those of squirrel monkeys. Leucocyte count, plasma total protein, albumin and calcium in cynomolgus monkeys were statistically higher than those of squirrel monkeys. Squirrel monkeys showed marked deviations in four assays from the other two species: ratio of lymphocytes to neutrophils, AST, ALT and urine volume.The results obtained in this study will be used as baseline data for haematology and clinical chemistry characteristics for three species of purpose-bred monkeys.     

Cross-linking of Newcastle disease virus (NDV) proteins

Summary The proxomity and spatial relationships of the structural proteins of Newcastle disease virus (NDV) were studied by chemical cross-liking with a series of imidoesters. When the virions were reacted by the cross-linker with a distance 6.1 Å or longer between the functional groups and analyzed by polyacrylamide gel electrophoresis, remarkable changes were observed in the migration patterns of the viral proteins. The most striking one was the extensive decrease in the intensity of the M protein band, and although not so strikingly, glycoprotein and nucleocapsid protein bands were reduced significantly. Instead, several protein complexes appeared at and near the top of the gels. The protein complexes formed by a reversible cross-linker, dimethyl-3,3-dithiobispropionimidate (DTBP), were analyzed by two dimensional electrophoresis; the complexes on the first-dimension cylindrical gels were cleaved by reduction with 2-mercaptoethanol and electrophoresed laterally on the second-dimension slab gels. The results indicated that homodimers of glycoprotein, nucleocapsid protein and M protein were generated under the condition of the most gentle cross-linking employed. At the same time, however, trimer and higher homopolymers of M protein were already detectable. Under the more extensive conditions, the bulk of M protein was cross-linked to form a large protein complex with very high molecular weight. Further, small but significant amounts of glycoprotein and nucleocapsid protein were always detected in this complex.These results suggest that M protein may be present in the virion in close enough proximity to interact with each other and may further have some interactions with glycoprotein and nucleocapsid protein. On the basis of these findings possible roles of M protein in virus assembly were discussed.With 6 Figures     

IMMUNOHISTOCHEMICAL LOCALIZATION OF TYPE I, II, III, AND IV COLLAGENS IN THE LUNG

Type specific rabbit antibodies to bovine type I, 11, 111, and IV (basement membrane) collagens showing no cross-reaction with other types of collagen were prepared by cross-adsorption and diethylamiuoethyl-cellulose romatography. The antibodies to bovine type I and I11 collagens showed a high cross-reaction with the corresponding human collagens, but those to type I1 and IV collagens did moderate and no cross-reactions with human type I1 and IV collagens, respectively. By using these antibodies, tissue distribution of various types of collagen in normal bovine lung was examined by indirect immunofluorescence microscopy. Both type I and I11 collagens were found to distribute widely in the interstitium of bronchial tree, bronchial
lamina propria and of interlobules as well as alveolar nipples and adventitia of pulmonary arteries. Type I1 collagen was located only in bronchial cartilage. The tissues mainly stained for type 11 collagen were the alveolar interstitium (also stained faintly for type I collagen) and the intima and media of the arteries. Type IV collagen was located in a membranous fashion in alveolar septa and bronchial smooth muscles and subepithelial layers as well as capillaries and the intima and media of arteries. ACTA PATHOL. JPN. 31: 601–610, 1981.