PubMed HealthSearch

Biomedical subjects

T D Chugh

Publications and source records attributed to T D Chugh.

At least 19 recordsLinked to original sources

An investigation of patients with pulmonary tuberculosis in Kuwait in preparation for studies of immunotherapy with Mycobacterium vaccae.

Sixty-five patients, many of them immigrant to Kuwait, with bacteriologically proven, adult type, pulmonary tuberculosis were studied by many parameters over the 4 months following diagnosis. Twelve were infected with tubercle bacilli resistant to at least one anti-tuberculosis drug. Preliminary evidence suggested that this was frequently primary resistance in patients infected in their countries of origin. The Kuwaiti environment results in very high skin test and lymphocyte proliferative responses (LTT) to shared and species specific antigens of mycobacteria in healthy persons. In comparison, patients with tuberculosis lacked cellular responses to group i and group ii antigens, but had increased IgG and IgA binding to mycobacterial antigens in general. LTT responses to added interleukin 2, and production of alpha interferon, were normal in our patients, but induction of gamma interferon in response to phytohaemagglutinin was reduced initially, rising towards normal during treatment. Biochemical and haematological abnormalities present at the time of diagnosis rapidly corrected. The disease differed from that reported in most previous studies in that fever was uncommon, the disease was never fatal, and most tuberculin tests were not necrotising. This implied that a detrimental immunopathological component is less pronounced in those exposed to the Kuwaiti environment, and a hypothesis is put forward to explain this.

Adolescent

Immunotherapy with Mycobacterium vaccae as an adjunct to chemotherapy in the treatment of pulmonary tuberculosis.

47 patients with adult-type pulmonary tuberculosis attending the Chest Diseases Hospital in Kuwait were given a single injection of 10(9) irradiation-killed M. vaccae after 1 month of a 9-month course of chemotherapy. The patients were followed-up for 3 more months in double blind comparison with 65 patients given an injection of saline (placebo). The immunotherapeutic injection produced a small local lesion in 44/47 patients, 18 of which ulcerated and produced small scars. Immunotherapy made no measurable difference to the bacteriological, biochemical, haematological, or radiological parameters measured. However it was associated with significantly improved weight gain, reduced size of skin test response to Tuberculin, increased lymphocyte proliferation to common mycobacterial antigens, and increased antibody levels to mycobacterial antigens. The changes in skin test and LTT responses were related and occurred in 29% of patients whose recognition of common mycobacterial antigens returned to normal. The remaining patients did not differ in these respects from those receiving placebo. The proportion of patients whose responses were improved was very similar to that achieved using the same immunotherapeutic agent in a group of treated multibacillary leprosy patients.

Adolescent

Improved immunotherapy for pulmonary tuberculosis with Mycobacterium vaccae.

We previously demonstrated that a single intradermal injection of 10(9) irradiation-killed M. vaccae, given 1 month after starting chemotherapy, caused significant changes in responses to mycobacterial antigens. Amongst 38 patients with pulmonary tuberculosis, 29% had lymphocytes responding to common myocobacterial antigens after the injection, compared with only 11% of 49 similar patients after an injection of saline (p less than 0.03). To increase the proportion of responders to these antigens, six modifications of the potentially immunotherapeutic injection, randomized with injections of saline, have been assessed by biochemical, clinical, haematological, immunological and radiological criteria. Subsequent lymphocyte proliferation to mycobacterial antigens enabled the modifications to be ranked in order of efficacy. Tuberculin plus murabutide plus 10(9) irradiated M. vaccae (36% of 25), an autoclaved preparation of 10(9) M. vaccae (45% of 22), and 2 x 10(9) irradiated M. vaccae (75% of 12) were the most effective. Antibody responses in several IgG subclasses to mycobacteria, but not streptococci, were also significantly increased by the most effective modifications over the 8 weeks following injection. Detailed radiological study showed that use of the autoclaved bacilli was followed by a delay in clearing of consolidation, but by better closing of cavities than was found in the control group, suggesting enhanced, or altered, immunological activity around the lesions.

Acetylmuramyl-Alanyl-Isoglutamine

Adherence of Staphylococcus epidermidis to fibrin-platelet clots in vitro mediated by lipoteichoic acid.

The adherence of two strains of Staphylococcus epidermidis to human fibrin-platelet clots in vitro was investigated. Both strains were noncapsulated, nonhemagglutinating, and nonslime producers. Binding was not related to surface charge, carbohydrate profile, or hydrophobicity of the bacteria. Adherence was reduced four- to sixfold (P less than 0.001) on pretreatment of bacteria with lipase, while neuraminidase, trypsin, phospholipase C, and sodium periodate did not alter their binding. Pretreatment of bacteria with substances known to bind lipoteichoic acid (LTA), such as human albumin and anti-LTA antibodies, also resulted in a fourfold (P less than 0.001) reduction in adherence. Prior incubation of clots with free LTA, but not with deacylated LTA, produced a fourfold (P less than 0.001) decrease in the adherence of homologous and heterologous strains of S. epidermidis. A similar reduction was also observed when LTAs derived from Staphylococcus aureus and Streptococcus pyogenes were used. These data provide evidence that the lipid moiety of LTA has a central role in the adherence of S. epidermidis to fibrin-platelet clots in vitro.

Bacterial Adhesion

Tissue lipids in leprosy.

A total of 30 cases of leprosy (15 lepromatous and 15 tuberculoid) were studied by histochemical procedures for lipids in the morbid skin. The possible origin and relation of lipids to the presence of lepra bacilli in the lepra cells is discussed.

Cholesterol