Abnormal lipid metabolism in collagen-induced arthritis rat model: In vitro, high resolution NMR spectroscopy based analysis.

Collagen-induced arthritis (CIA) was induced in female Wistar rats by intradermal injection of porcine immunization grade native collagen type II (Chondrex). Development and progression of CIA was monitored by studying histopathological, radiographical and biochemical features of arthritic manifestations in the knee joints, hind limb and blood plasma. In addition, oxidative stress status of arthritic animals was determined by measuring lipid peroxidation and the antioxidant enzymes: catalase, superoxide dismutase and glutathione peroxidase. High resolution proton NMR spectroscopy was employed for the analysis of lipid components in the lipid extracts of the joint tissue and plasma of collagen-induced arthritic and control rats. Triglyceride levels showed significant decreases in plasma (1.7 times) but were unchanged in the joint tissue of CIA rats as compared to control. One-dimensional proton NMR spectra showed a 6.2 times reduction in the quantity of choline-containing phospholipids in the plasma of CIA as compared to control rats. There was a 1.6 times elevation of choline-containing phospholipids in the joint tissue of CIA rats as compared to controls. Induction of arthritis showed a 4.0 times reduction in the level of total cholesterol in the plasma and 1.6 times elevation in the joint tissue of CIA rats as compared to controls. The ratio of saturated fatty acids to unsaturated fatty acids was 1.5 times significantly higher in joint tissue and 2.1 times significantly higher in plasma of CIA rats as compared to controls. The results demonstrated significantly altered lipid patterns in the joint tissue and plasma of collagen-induced arthritic rats as detected by one- and two-dimensional NMR spectroscopy compared with controls.

Verotoxic Escherichia coli (STEC) from beef and its products.

In the present investigation, out of 27 (24.10%) strains of Escherichia coli isolated from 112 beef samples comprising raw meat (45), kabab (36) and kofta (31), 9 (33.33%) belonging to 7 different serotypes were verotoxic as tested by vero cell cytotoxic assay. Serotype O145 was the predominant STEC in raw meat. Interestingly, one STEC-O157 strain was also detected. All the STEC strains were positive for Stx genes by polymerase chain reaction showing stx2 (77.78%) to be most predominant followed by stx1 (22.22%). Phenotypic enterohaemolysin production on washed sheep blood agar supplemented with CaCl2 revealed 6 (66.67%) STEC strains to be positive. Presence of STEC in cooked beef products, viz., kabab and kofta appeared to be a matter of concern and potential threat to public health.