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Biomedical subjects

V N Bhatia

Publications and source records attributed to V N Bhatia.

At least 19 recordsLinked to original sources

Specificity of IgG subclass antibodies in different clinical manifestations of leprosy.

We analysed specific IgG subclasses levels to Mycobacterium leprae sonicate extract (MSE), lipoarabinomannan B (LAM) and phenolic glycolipid I (PGL-I) in the sera of leprosy patients with different clinical manifestations. IgG2 was found to be the predominant antibody to MSE regardless of clinical manifestations, and IgG1 response was mostly seen in lepromatous patients. IgG3 reacted only rarely but IgG4 reacted relatively more in certain clinical groups such as borderline lepromatous and lepromatous with erythema nodosum leprosum (ENL) reaction. Most of the IgG subclass responses to MSE could be accounted for reactivity with LAM, suggesting that LAM is the major immunogen involved in the pathogenesis of leprosy. In contrast to LAM, PGL-I antigen showed considerably lower reactivities for IgG subclasses. An association between IgG subclass responses and clinical manifestations of leprosy was also seen. Whereas borderline lepromatous patients were found to have significantly higher levels of IgG2 and IgG4 to MSE, lepromatous patients had elevated levels of IgG1 and lower levels of IgG2. An interesting observation, however, was the significantly higher levels of IgG2 to LAM in the pure neuritic leprosy patients.

Analysis of Variance

Serum zinc/copper ratio in subtypes of leprosy and effect of oral zinc therapy on reactional states.

Serum zinc and copper levels and zinc/copper ratios were studied in 86 healthy controls, 45 cases of borderline tuberculoid (BT), 31 cases of borderline lepromatous (BL), 117 cases of lepromatous (LL) leprosy patients, 16 cases with severe erythema nodosum leprosum (ENL) reaction, and 16 cases with ENL reaction receiving oral zinc therapy. A significant reduction in serum zinc levels was noticed in all types of leprosy, the maximum decrease being seen in cases with ENL reaction. Conversely, the copper levels were significantly increased from BT to LL cases with ENL reaction in a progressive manner. A very good negative correlation (r = -0.998) was noticed between mean serum zinc and copper levels from healthy controls to active LL cases with ENL reaction. After oral zinc therapy, the serum zinc levels were significantly increased in all of the 16 LL patients with ENL reaction. In contrast, the copper levels were not decreased, indicating that oral zinc therapy can restore normal zinc levels in leprosy patients but is unable to reduce the increased copper levels.

Administration, Oral

ELISA & lepromin skin tests in household contacts of leprosy patients.

A total of 438 household contacts of leprosy patients and 228 non-contacts were studied for anti-PGL-I antibodies and cell mediated immune response to Mycobacterium leprae using ELISA and lepromin tests. The contacts showed relatively higher positivity to ELISA (29.4%) and lepromin (70.5%) as compared to non-contacts who showed 9.6 and 57 per cent positivity. In contacts as well as non-contacts the seropositivity was not found to be influenced by age and sex. However, seropositivity was higher (39.7%) in the contacts of patients with multibacillary leprosy as compared to contacts (27.7%) of patients with paucibacillary leprosy.

Adolescent

Serum beta-glucuronidase in subtypes of leprosy.

Serum beta-glucuronidase activity was estimated using phenolphthalein mono-beta-glucuronic acid as substrate in 176 individuals including 72 lepromatous leprosy patients, 24 patients of borderline leprosy, 42 of borderline tuberculoid and 38 healthy controls. Of these, 35 patients (20 with lepromatous leprosy, 5 with borderline leprosy and 10 with borderline tuberculoid) were untreated. The enzyme levels were increased significantly in all types of leprosy, the highest levels being seen in treated lepromatous leprosy patients (105.0 SU). There was also a significant difference in the enzyme activity between untreated patients and those on combined dapsone and rifampicin therapy, in all three types of leprosy. Among untreated patients, the maximum value observed in lepromatous leprosy was 93.4 SU. The lowest enzyme level in healthy control was 19.5 SU and the maximum was 54.0 SU. The results suggest that in leprosy patients, especially in those on daily multidrug regimens, there is an extensive damage of leucocytes and liver cells where the enzyme is largely present.

Female

LDH isoenzyme as a tool for the identification of mycobacteria.

Using Polyacrylamide gel electrophoretic technique, the lactate dehydrogenase (LDH) isoenzyme patterns have been studied in four slow growing mycobacteria viz. Mycobacterium tuberculosis, M. avium, M. microti, and M. bovis and four rapid growing mycobacteria viz. M. Fortuitum, M. parafortuitum, M. thermoresistible and M. diernhoferi. Each mycobacterial species exhibited distinct isoenzyme pattern for LDH.

Electrophoresis, Polyacrylamide Gel

Observations on T-cell sub-populations in type II reactions.

15 cases each of Type II Reaction, LL and TT Leprosy and 50 endemic controls were studied for phenotypic markers T2, T4 and T8 by 2 step immunoperoxidase technique. There was statistically significant increase in T4 (helper) cells in Type II Reaction. There was also a decrease in T8 cells but this was not statistically significant.

Adult

Morphology of M. leprae (?) in VS3E medium--a preliminary communication.

In a previous attempted culture of M. leprae in VS2M medium non-acid fast organisms were seen initially and acid fast organisms appeared later. A drop of a sonicated suspension from a subculture of this was inoculated in VS3E medium. The inoculum consisted mostly of acid fast granules. The culture yielded pure growth of acid fast organisms. Morphology typical of M. leprae could be seen only after 60th day of culture.

Culture Media

Effect of temperature, cholesterol and nerve tissue on multiplication of armadillo M. leprae.

The effect of temperature, nerve tissue and certain constituents of the medium on multiplication of armadillo M. leprae was studied using Hanks BSS. An equal or better growth was seen at 30 degrees C and 10 degrees C compared to 37 degrees C. Multiplication was also seen at -20 degrees C. Adding cholesterol, foetal calf serum, cystine-HCl, sodium thioglycollate or nerve suspension and covering medium with liquid paraffin each showed beneficial effect. Hanks containing foetal calf serum, cholesterol with sodium thioglycollate or cystine-hydrochloride showed maximum multiplication. These combinations may be used for testing additional factors for further improvement of the medium.

Animals

Use of eluates of filter paper blood spots in ELISA for the serodiagnosis of leprosy.

Blood samples were collected from 59 leprosy patients and 35 normal healthy subjects by veni-puncture and finger prick methods to obtain serum samples and blood spots on filter paper respectively. The serum samples at 1:300 dilutions and the eluates of dried blood spots at 1:40, 1:80, 1:160 and 1:320 dilutions were applied in ELISA to measure the antibody levels (IgM) against synthetic ND-O-BSA antigen. The antibody levels were found to be high in the multibacillary leprosy patients than the pauci-bacillary patients irrespective of whether serum samples or eluates were used. The OD values obtained at 1:160 dilution of the eluates were equivalent to that of values obtained at 1:300 dilution of the serum samples. The positivities differ in different dilution of the eluates, showing the highest in the 1:40 dilution and the lowest in the 1:320 dilution.

Blood Specimen Collection

Auramine staining in detecting small number of bacilli in skin smears.

Auramine staining has been compared with Ziehl-Neelsen's staining of M. leprae in skin smear slide. The auramine method was found to be more sensitive than Ziehl-Neelsen's method and may be useful in detecting small number of M. leprae in skin smears. The inter-observer variance was minimal with auramine staining.

Bacteriological Techniques