An immunodominant 30-kDa antigen of a candidate anti-leprosy vaccine,Mycobacterium w,shares T and B cell determinants withM. leprae andM. tuberculosis

Earlier we reported that vaccination of leprosy patients withMycobacterium w induces an immune response directed predominantly against low molecular weight antigens. One of these antigens, with a molecular mass of 30-kDa, was recognized by a majority of the vaccinated subjects as well as the tuberculoid leprosy patients and healthy contacts. In the present communication we report further characterization of this antigen. Immunofluorescence and Western blot studies with antibodies raised against this antigen demonstrate that it is associated with the cell surface and has homologues present inM. leprae andM. tuberculosis. Delayed-type hypersensitivity studies carried out in guinea pigs immunized with the 30-kDa antigen show that in addition to sharing B cell determinants, this immunodominant antigen ofM. w also shares T cell determinants withM. leprae andM. tuberculosis.     

Association of HLA antigens with differential responsiveness toMycobacterium w vaccine in multibacillary leprosy patients

Leprosy patients undergoing phase II trials in two hospitals of New Delhi, India, were HLA typed to see the association of HLA with differential responsiveness toMycobacterium w vaccine. The vaccine comprises an atypical, nonpathogenic mycobacterium,Mycobacterium w, which has cross-reactive antigens withM. leprae. Multibacillary patients who are lepromin negative are vaccinated at an interval of 3 months. Considerable improvement is evident in the patients in terms of a decline in bacterial indices and histopathological and immunological upgrading. But all the patients do not respond to the vaccine in the same manner; some are slow responders, while others are good responders. HLA-A28 and DQw3 (DQw8+9) were found to be associated with slow responsiveness, while DQw1 and DQw7 were found to be associated with a more rapid responsiveness to theM. w vaccine. However, these associations were not significant afterP correction for the number of antigens tested for each locus except for HLA-DQw3 (DQw8 and DQw9) and DQw7. DQw7, a new defined split of HLA-DQw3, seems to be associated with the responsiveness toM. w vaccine.     

Comparative study of oral and intramuscular atropine sulphate as a premedicant in paediatric age group

The use of atropine sulphate in the paediatric age group as a premedicant orally in a dosage of 0.02 mg/kg body weight 70 minutes prior to surgery was found to be as effective as atropine sulphate given intramuscularly 35 minutes prior to surgery in a dosage of 0.01 mg/kg body weight. This avoids the unpleasant memory of needle prick; The duration of effect as studied in the normal healthy children not subjected to surgery was found to be 2 1/2-3 hours.     

Role of Periductal and Ductular Epithelial Cells of the Adult Rat Pancreas in Pancreatic Hepatocyte Lineage: A Change in the Differentiation Commitment

Development of pancreatic hepatocytes in adult rats maintained on copper deficient diet containing 0.6% trien (CuDT) has been reported recently. To elucidate the histogenesis of hepatocytes a sequential study was undertaken using morphologic, histochemical, immunochemical, in situ hybridization, and Northern blot analysis. Male F-344 rats weighing 80 to 90 g were fed CuDT for 8 weeks and returned to normal rat chow. Beginning from 4 weeks of copper depletion, there was a progressive loss of acinar cells and by 8 weeks more than 90% of the acinar tissue was lost. During this period, there was an increase in the number of adipocytes in the interstitium, and in the number of interstitial and ductular cells. Morphologic observations were confirmed by immunoblot and Northern blot analysis, in which the amount of pancreatic proteins and their mRNAs decreased between 5 and 8 weeks. During this period, a progressive increase in the level of albumin mRNA was observed. In situ hybridization, performed at 7 weeks of copper deficiency, showed localization of albumin mRNA over interstitial and ductular cells. Pancreatic hepatocytes were identified immediately after the rats were returned to a normal diet and gradually increased in number. The hepatocytes occupied almost 60% of the pancreatic volume by 8 weeks. During the early recovery phase, hepatocytes were identified in ductules as well as in the interstitium. Based on these studies, it is concluded that both the ductular cells and interstitial cells, which resemble oval cells of liver, are capable of transforming into pancreatic hepatocytes and these cells may be considered stem-cell equivalent.     

Conceptual and methodologic challenges of assessing the short-term efficacy of Guggulu in obesity: data emergent from a naturalistic clinical trial

An open comparative trial was conducted in 58 adult obese patients (Body Mass Index > or = 25 kg/square metre). Group I (n = 27), non-drug, was advised diet (1200-1600 cals) and a brisk walk for 30 minutes. Group II, in addition, received Guggulu (Medohar) 1.5-3 gms/day for 30 days. Mean difference in weight loss between Guggulu and non-drug group was 0.32 kg (ns) on day 15 and 0.58 kg on day 30 (ns). The mean weight reduction in patients (> 90 kgs) was 1.92 kg (ns) and 2.25 kg (ns) higher in Guggulu group. All patients weighing > 90 kg lost weight in Guggulu group whilst 3 in non-drug group did not lose weight. Guggulu was tolerated well. The data from this pilot study suggest a synergistic diet-Guggulu interaction over 30 days in patients weighing > 90 kgs which needs to be confirmed in a large placebo controlled study.     

Interphase cytogenetics using biotin and digoxigenin labelled probes II: Simultaneous differential detection of human and papilloma virus nucleic acids in individual nuclei.

A method was developed for the simultaneous detection of viral and human DNA in contrasting colours in routine formalin fixed, paraffin wax embedded biopsy specimens. This was achieved by non-isotopic in situ hybridisation (NISH) with a biotinylated Y chromosome probe and digoxigenin labelled probe for human papilloma virus type 6 (HPV 6). The tissues studied were peripheral lymphocytes, tonsil, and penile warts. The hybridisation signals produced by biotinylated probes were visualised in red using streptavidin peroxidase and those produced by digoxigenin labelled probes as a blue/black colour using anti-digoxigenin alkaline phosphatase. In lymphocytes and tonsil 95-100% of cells had a detectable Y chromosome; in warts only 60-70% of infected keratinocytes near the skin surface had a demonstrable Y chromosome. This suggests that this chromosome is lost or occluded in cell maturation. In simultaneous double hybridisation with both probes, HPV and Y sequences were demonstrable within the same nucleus in penile warts. This technique permits the simultaneous differential detection of two nuclei acid sequences in interphase nuclei and will have application in analysis of putative dual HPV infections and in determining the intranuclear spatial relations between nucleic acids in interphase nuclei.     

Integrated YAC Contig Map of the Prader–Willi/Angelman Region on Chromosome 15q11–q13 with Average STS Spacing of 35 kb

Prader–Willi syndrome and Angelman syndrome are associated with parent-of-origin-specific abnormalities of chromosome 15q11–q13, most frequently a deletion of an ~4-Mb region. Because of genomic imprinting, paternal deficiency of this region leads to PWS and maternal deficiency to AS. Additionally, this region is frequently involved in other chromosomal rearrangements including duplications, triplications, or supernumerary marker formation. A detailed physical map of this region is important for elucidating the genes and mechanisms involved in genomic imprinting, as well as for understanding the mechanism of recurrent chromosomal rearrangments. An initial YAC contig extended from D15S18 to D15S12 and was comprised of 23 YACs and 21 STSs providing an average resolution of about one STS per 200 kb. To close two gaps in this contig, YAC screening was performed using two STSs that flank the gap between D15S18 and 254B5R and three STSs located distal to the GABRA5–149A9L gap. Additionally, we developed 11 new STSs, including seven polymorphic markers. Although several groups have developed whole-genome genetic and radiation hybrid maps, the depth of coverage for 15q11–q13 has been somewhat limited and discrepancies in marker order exist between the maps. To resolve the inconsistencies and to provide a more detailed map order of STSs in this region, we have constructed an integrated YAC STS-based physical map of chromosome 15q11–q13 containing 118 YACs and 118 STSs, including 38 STRs and 49 genes/ESTs. Using an estimate of 4 Mb for the size of this region, the map provides an average STS spacing of 35 kb. This map provides a valuable resource for identification of disease genes localized to this region as well as a framework for complete DNA sequencing.     

The pathogenesis of rat virus infection in infant and juvenile rats after oronasal inoculation

Summary The pathogenesis of rat virus (RV) infection was studied in random-bred Sprague-Dawley rats after oronasal inoculation of a recent RV isolate designated RV-Yale (RV-Y). RV-Y was pathogenic for rats inoculated as infants (2 days) whereas rats inoculated as juveniles (4 weeks) had asymptomatic infection and no lesions. Rats inoculated as infants developed pantropic infection accompanied by hepatic necrosis, granuloprival cerebellar hypoplasia and hemorrhagic encephalopathy. Virological and serological studies showed that virus could persist in inoculated rats for at least 35 days and for at least 28 days after seroconversion was first detected. Immuno-histochemical results indicated that RV-Y infects tissues conducive to virus excretion including kidney and lung. RV-Y also was found in genital tissues of some rats. Athymic juvenile rats inoculated intraperitoneally with RV-Y had a poor humoral immune response and harbored infectious virus for at least 3 weeks, whereas infection in euthymic control rats was detected for 1 week. These studies indicate that RV-Y can persists in the presence of humoral immunity and suggest that transmission of infection could occur for a substantial period after seroconversion. They also suggest that immunodeficient rats have increased susceptibility to persistent infection.     

Insulin effects in clarias batrachus L.: a combined biochemical and anatomical study

The effect of mammalian insulin was studied in a freshwater fish, Clarias batrachus, at both high and low ambient temperatures. The hormone produced a significant but delayed, yet recoverable, lowering of blood glucose, a concurrent decrease in liver glycogen, and an increase in the glycogen content of muscles. The decrease in brain glycogen occurred during advanced hypoglycemia. Hypoglycemic seizures developed intermittently in most of the fishes whose plasma glucose and brain glycogen levels had been considerably depleted. Necrobiotic changes in the pancreatic islets, including degranulation and atrophy, and necrosis of B cells, were seen in the treated fish. In some cases damage to A cells and the acinar tissue was also observed. With the restitution of normal glucose and glycogen values, the islet cells also seemed to have recuperated. Changes in glycemia, glycogen, and the islets were more pronounced in the fishes held at 24 degrees C than in those at 10 degrees C, indicating that the ambient temperature plays an important role in blood glucose homeostasis as well as insulin.