Characterization of fibronectin metabolites in normal rat urine

Fibronectin fragments showing immunoreactivity against an anti-rat plasma fibronectin antibody were detected in normal rat urine. Untreated urine showed immunoreactivity and this reactivity could not be dialyzed. These rat urinary fibronectin-related substances (RUF) were adsorbed on heparin-immobilized gel but hardly at all on gelatin-immobilized gel. They were separated into three fractions by DEAE-Sephadex ion exchange chromatography and each fraction was further purified by heparin-Sepharose affinity chromatography. The partially purified preparations, RUF-1, RUF-2 and RUF-3, were analyzed by the sandwich-type enzyme-linked immunosorbent assay (ELISA) method, and it was found their maximum reactivities were about 30%, 45% and 20% that of the intact plasma fibronectin, respectively. Plasma fibronectin was digested with elastase and then analyzed by the ELISA method to elucidate the patterns shown by the fragments. The fragments showed almost the same patterns on ELISA analysis, and the maximum immunoreactivity decreased in parallel with the degradation. On SDS-polyacrylamide gel electrophoresis, the RUF preparations were found to be composed of multiple forms of molecules, Mr 15,000-100,000, which reacted with the antibody. These results suggest that various forms of fibronectin metabolites are excreted in normal rat urine.     

Hemagglutinin prepared from cells of Aedes albopictus, clone C6/36, infected with type 1 dengue virus

A high titer of hemagglutinin (HAnin) was found in culture fluids of cells of Aedes albopictus, clone C6/36, infected with type 1 dengue virus. The HAnin (TC antigen) was associated with complete virions and no appreciable small-sized HAnin was produced, in contrast to the case in an infected suckling mouse brain (SMB) homogenate, in which most of the HAnin is smaller than complete virions. Extraction of the TC antigen with Tween 80-ether disrupted the HAnin into smaller-sized particles, resulting in complete loss of infectivity (TE-TC antigen), but it did not affect the titer or reactivity of the HAnin. Comparative hemagglutination-inhibition (HI) assay of human sera using TC antigen, TE-TC antigen or standard antigen extracted from infected SMB (SMB antigen) showed that TC or TE-TC antigen could be used for routine diagnostic or epidemiological HI tests instead of SMB antigen, which is rather hard to prepare.     

Streptococcus pyogenes upregulates arginine catabolism to exert its pathogenesis on the skin surface

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A modified PAP (peroxidase-anti-peroxidase) staining technique using sera from patients with dengue hemorrhagic fever (DHF): 4 step PAP staining technique.

BHK-21 cells infected with dengue virus type 1 were stained by a newly developed 4 step PAP (peroxidase-anti-peroxidase) technique using sera from patients with dengue hemorrhagic fever as anti-virus antibody. The intensity of staining of the sera was proportional to the hemagglutination inhibition and neutralization titers. With this new technique using sera from patients it should be possible to use the PAP technique of virus infections.     

A staphylococcal coagglutination test for detecting and serogrouping Legionella pneumophila

For detection of Legionella pneumophila and determination of its serogroup, the modified staphylococcal coagglutination test was studied in detail. Cross-reactions in serum-agglutination tests were observed among serogroups, but immunoglobulin-coated staphylococcal cells could detect L. pneumophila with high sensitivity (a cell concentration with an absorbance of 0.008 at 660 nm could be detected) and serogroups could be determined without cross-reactions. Moreover the coexistence of other bacteria did not affect the results of the test. These results suggest that the staphylococcal coagglutination test is useful for detection and identification of Legionella, especially in environmental samples, and for serogrouping of isolates of L. pneumophila from clinical specimens.     

Effect of Physical Training and Its Cessation on Percent Fat and Bone Density of Children with Obesity

GUTIN, BERNARD, SCOTT OWENS, TOMOKI OKUYAMA, SHARON RIGGS, MICHAEL FERGUSON, AND MARK LITAKER. Effect of physical training and its cessation on percent fat and bone density of children with obesity. Obes Res. Objective We determined the effect of 4-month periods of physical training (PT) and detraining on percent fat (percent fat) and bone density of children with obesity. Research Methods and Procedures Subjects were 79 7- to 11-year-old children with obesity; 34 were white, 44 were black, and 1 was Asian, 26 were male and 53 were female. They were randomly assigned to two groups: group 1 engaged in PT for the first 4 months, while group 2 engaged in PT during the second 4 months. Body composition was measured with dual energy absorptiometry, and diet was measured with 4 days of recall for each 4-month period. PT was offered 5 dayslweek for 40 minuteslsession, heart rate monitors were worn, and no dietary information was given; mean attendance was 80%, and mean heart rate per session was 157 bpm. Results Group by time interactions across the three time-points (from analysis of variance) were significant for percent fat (p = <0.001) and bone density (p = 0.045). Both groups declined in percent fat during the periods of PT, by an average of 1.6 %fat units; in the 4 months after cessation of PT, group 1 increased by 1.3 %fat. In both groups, bone density increased more during periods of PT (0.025 g/cm²) than during periods of no PT (0.010 g/cm²). No significant PT vs. no-PT differences were found for dietary intake of energy, macronutrients, or calcium. Discussion This study suggests that regular exercise, without dietary intervention, can enhance the body composition of children with obesity.