Molecular Speciation of Mycobacterial Isolates from Raw Cow Milk Reveals Predominance of Mycobacterium chelonae

Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Owing to the fact that raw milk intake is still practiced in selected communities globally, milk borne...     

Investigation of the Immunomodulatory Potential of Oryzanol Isolated from Crude Rice Bran Oil in Experimental Animal Models

Nutrition and nutritional status can influence the development, maintenance and optimal functioning of the immune system. Oryzanol (OZ), a commercially important bioactive phytochemical component of rice bran oil, has generated global interest on account of its several beneficial physiological effects on human health. The aim of the present investigation was to examine the effect of OZ, isolated from crude rice bran oil (cRBO), on the regulation of the immune response in experimental animal models. The isolated OZ was identified with respect to the standard by melting point determination, thin‐layer chromatography (TLC), UV‐visible spectrophotometry and high‐performance liquid chromatography (HPLC). Cellular immunity in rats was assessed by carbon clearance assay, delayed‐type hypersensitivity (DTH) response and cyclophosphamide‐induced myelosuppression, whereas humoral immunity was analysed by haemagglutinating antibody (HA) titre assay. Oryzanol (25, 50 and 100 mg/kg, p.o.) evoked a significant increase in antibody titre values in the haemagglutination test and potentiated the delayed type hypersensitivity reaction induced by sheep red blood cells. It also significantly ameliorated myelosuppression in cyclophosphamide treated rats and showed an increase in phagocytic index in the carbon clearance assay. The findings from the study indicate that OZ possesses sufficient potential for augmenting immune activity by cellular and humoral mediated mechanisms. Copyright © 2012 John Wiley & Sons, Ltd.     

Isolation of verotoxin producing Escherichia coli from diarrhoeal and urinary tract infection patients

Fourty nine Escherichia coli strains, isolated from diarrhoeal and urinary tract infection (UTI) patients, attending Bareilly district hospital, Uttar Pradesh during October to December, 1998 were screened for verotoxin (VT) production by Vero cell assay. Five strains produced characteristic cytopathic effect on Vero cell line, of which 4 were from diarrhoeal and one was from UTI-patient. The level of VT-production varied widely. Antibiotic sensitivity tests revealed that the VT-producing E. coli (VTEC) were mostly sensitive to kanamycin, norfloxacin and nalidixic acid but resistant to ampicillin and tetracycline.     

Effect of Plasmodium yoelii nigeriensis infection and chloroquine on the hepatic mixed function oxidase system of mice

Plasmodium yoelii nigeriensis infection in albino mice significantly altered the hepatic microsomal mixed function oxidase system. Cytochrome P-450 (the terminal monooxygenase) and other monooxygenases, viz. aniline hydroxylase, aminopyrine-N-demethylase and benzo(a)pyrene hydroxylase were significantly lowered while microsomal heme showed 4-fold increase at 80% parasitaemia. Noticeable impairment in the other components like NADH:cytochrome b5 reductase, NADPH:cytochrome c reductase, cytochrome b5 and glucose-6-phosphatase was also observed. Oral treatment of normal and P. y. nigeriensis infected mice with chloroquine (64 mg per kg body weight for 4 days) caused lowering of mixed function oxidase activities which however showed a recovering trend, a week after cessation of treatment.     

Selective strain distribution pattern of a germline VH gene for a pathogenic anti-DNA autoantibody family

Autoimmune NZB mice rarely develop nephritis, but the SNF1, progeny of Crosses between NZB and the normal SWR strain uniformly develop severe lupus nephritis, indicating that the normal SWR strain makes a genetic contribution to the development of nephritis. The SNF1 mice produce a select population of cationic IgG anti-DNA autoantibodies that share a recurrent cross-reactive idiotype called Id564 and these autoantibodies play a prominent role in the development of nephritis. These pathogenic autoantibodies of SNF1 possess the IgCH allotype of the SWR, indicating their origin from the normal parent. The leader-VH sequences of these Id564+ pathogenic anti-DNA autoantibodies are highly homologous and they are also related by 95% homology to a germline gene of normal C57BL/6 mice, called VH-23, that is a member of an anti-NP antibody gene family. Herein, we cloned the flanking and coding regions of the expressed VHDJH genes of the anti-DNA mAb 564, the prototype member of the pathogenic Id564 family. By restriction analysis and partial sequencing, we found that the VH564 gene is related but distinct in its 5' flanking region from all of the known anti-NP VH genes of C57BL/6 and BALB/c mice. Hybridization with four probes complementary to different segments of the flanking and coding regions of the expressed VH564 gene indicated that the germline gene for VH564 is contained in an approximately 5.2 kb EcoRI fragment of SWR genomic DNA. Moreover, high stringency hybridization with oligonucleotide probes complementary to unique CDR2 and 5' flanking sequences of the expressed VH564 gene revealed that the 'approximately 5.2 kb' germline allele for VH564 that is possessed by the normal SWR parental strain is lacking in the NZB parental strain. C57BL/6 mice also lack this allele of the anti-DNA VH564 germline gene, although this strain possesses the highly homologous, anti-NP-related VH-23 germline gene. Thus germline VH genes for certain pathogenic autoantibodies may have a selective strain distribution pattern.     

Fenestrated blood vessels in human skeletal muscle

Summary In a fine structural study of 32 skeletal muscle biopsies, rare examples of fenestrated blood vessels (FV) were found in three cases. In view of similar observations reported in a case of Duchenne muscular dystrophy, it is suggested that FV albeit rare may occur in skeletal muscle at least under pathologic conditions. These aberrant FV may be derived from adjacent dermis and/or epineurium which are known to contain occasional FV. Alternatively, the occurrence of fenestrae may reflect a nonspecific alteration in pre-existing continuous endothelium. The significance, if any, of their presence in skeletal muscle is unknown.