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Zarir F Udwadia

Publications and source records attributed to Zarir F Udwadia.

11 recordsLinked to original sources
PubMed2005

High incidence of the Beijing genotype among multidrug-resistant isolates of Mycobacterium tuberculosis in a tertiary care center in Mumbai, India.

We report a high frequency (35%) of the Beijing genotype among multidrug-resistant isolates recovered in and around Mumbai, India. Further restriction fragment-length polymorphism typing showed that these strains were closely related. We also report a high frequency of the Delhi genotype (31% of isolates). Our data indicate considerable ongoing transmission of multidrug-resistant Mycobacterium tuberculosis strains of the Beijing genotype in Mumbai.

Adolescent↗
PubMed2005

Application of multiplex ARMS and SSCP/HD analysis in molecular diagnosis of cystic fibrosis in Indian patients.

BACKGROUND: Cystic fibrosis (CF) is an autosomal recessive disorder caused by mutations in the CFTR gene. The most severe, DeltaF508, mutation accounts for nearly 70% of CF cases worldwide. Besides DeltaF508, there are other point mutations, namely G542X, G551D, R553X, N1303K, and 621+1(G-->T), which are common among Caucasians. Additionally, a polyT polymorphism in intron 8 is also involved in the pathogenesis of CF. However, neither the prevalence nor the types of mutations causing CF in India are known. In this study, we aimed at estimating the frequency of the above common mutations and polymorphism in clinically suspected CF cases. We also carried out partial analysis of the CFTR gene, limited to exons 10 and 11, to identify other variations in these exons. METHODS: The multiplex amplification refractory mutation system (ARMS) test was applied for rapid simultaneous analysis of six most common CF mutations, in 100 normal and 39 elevated sweat chloride cases. The scanning of exons 10 and 11 was carried out by single-stranded conformation polymorphism/heteroduplex (SSCP/HD) analysis, followed by DNA sequencing in 50 normal and 37 elevated sweat chloride cases. A single ARMS-polymerase chain reaction assay was used to distinguish the 5T, 7T, and 9T alleles in 100 normal and 33 elevated sweat chloride cases. RESULTS: The multiplex ARMS analysis identified the DeltaF508 mutation at an allele frequency of 24% in Indian CF cases. However, the other predominant CF mutations were found to be absent. The 7T polyT variant was observed to be the most common allele, followed by the 9T, and 5T, which was the lowest. The DeltaF508 mutation was observed in all instances with the 9T variant. The SSCP/HD and DNA sequencing additionally revealed a known polymorphism (M470V, exon 10) and a known mutation [1525-1(G-->A), intron 9]. The 1525-1(G-->A) mutation, observed in a single 4-year-old male, is predicted to code for a class II defective CFTR protein. CONCLUSION: The findings of this study suggest a difference in relative frequencies and spectrum of CFTR mutations in Indian CF cases. A larger screening study of the entire CFTR gene in clinically well defined CF cases is required to delineate common mutations in the CFTR gene and enable molecular diagnosis of CF in India.

Amino Acid Substitution↗
PubMed2005

Utility of the antigen-specific interferon-gamma assay for the management of tuberculosis.

PURPOSE OF REVIEW: The tuberculin skin test, now over a century old, is prone to reader variability, and outcomes are influenced by cross-reactivity with environmental mycobacteria, previous bacillus Calmette-Guerin (BCG) vaccination, and anergy in immunosuppressed individuals. More recently, T-cell-based interferon-gamma responses to Mycobacterium tuberculosis - specific antigens have been investigated for their role in diagnosing latent tuberculosis infection. RECENT FINDINGS: We review the evidence supporting the utility of the interferon-gamma assay for the diagnosis of latent tuberculosis infection (LTBI) in low-prevalence countries. We discuss the principle of the test, technical factors related to performance, and its utility in active tuberculosis, in specialised subgroups such as immunocompromised patients, and its applicability in developing countries. SUMMARY: Compared with the tuberculin skin test, the antigen-specific interferon-gamma assay, when used in a standardised protocol (overnight incubation assay using a combination of two antigens) for the diagnosis of LTBI, has greater specificity in BCG-vaccinated individuals, displays a stronger association with exposure, and is less biased by environmental mycobacteria such as Mycobacterium avium. Prospective studies are required, however, to confirm that treating LTBI, as defined by the interferon-gamma assay, will reduce the tuberculosis burden in low-prevalence countries and whether interferon-gamma responses are predictive of those who have a high risk of progression to active tuberculosis. Further studies are required to address the utility of the interferon-gamma assay in specialised subgroups of patients, in developing countries, and as a marker of disease activity.

Adult↗
PubMed2004

Pneumocystis pneumonia.

Explore the source record for details and available documents.

AIDS-Related Opportunistic Infections↗
PubMed2003

Prevalence of sleep-disordered breathing and sleep apnea in middle-aged urban Indian men.

No data are available on the prevalence of sleep-disordered breathing (SDB) and obstructive sleep apnea-hypopnea syndrome (OSAHS) in Indians. We conducted a two-phase cross-sectional prevalence study for the same in healthy urban Indian males (35-65 years) coming to our hospital in Bombay for a routine health check. We also investigated its risk factors and evaluated the significance of the most commonly asked questions that best correlated with the presence of OSAHS. In the first phase, 658 subjects (94%) returned completed questionnaires regarding their sleep habits and associated medical conditions. In the second phase, 250 of these underwent an overnight home sleep study. The estimated prevalence of SDB (apnea-hypopnea index of 5 or more) was 19.5%, and that of OSAHS (SDB with daytime hypersomnolence) was 7.5%. Multiple stepwise logistic regression determined body mass index, neck girth, and history of diabetes mellitus as the principal covariates of SDB. The presence of snoring, nocturnal choking, unrefreshing sleep, recurrent awakening from sleep, daytime hypersomnolence, and daytime fatigue was each statistically significant for identifying patients with OSAHS. The higher prevalence of OSAHS in urban Indian men is striking and may have major public health implications in a developing country.

Adult↗
PubMed2003

Incidence of multidrug-resistant tuberculosis in urban and rural India and implications for prevention.

We compared the incidence of multidrug resistance in 150 consecutive Mycobacterium tuberculosis isolates obtained from a rural center (in Sakawar, India) and an urban tertiary care center (in Mumbai, India). The study highlights an alarmingly high percentage of multidrug-resistant M. tuberculosis isolates in Mumbai (51%) as compared with that at the rural center (2%).

Antitubercular Agents↗