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1.
Lancet Reg Health Southeast Asia ; 29: 100457, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39258248

RESUMO

Background: India has the highest incidence worldwide of smokeless tobacco (SLT)-associated oral cancer, accounting for nearly 70% of all SLT users globally. Nicotine and tobacco-specific N-nitrosamines (TSNA) play critical roles in the addictive and carcinogenic potential, respectively, of SLT products. Our group has previously reported substantial variability in nicotine and TSNA levels across a small SLT product sample in India, calling for systematic surveillance. However, there is no information available on the current levels of these constituents in Indian SLT. Methods: We analysed 321 samples representing 57 brands of eight popular types of manufactured SLT products purchased from five local markets in Mumbai, India between August, and September 2019. The sampling locations were Mumbai Central, Kurla, Thane, Vashi, and Airoli. Product pH, moisture content, total and unprotonated (biologically available) nicotine, and TSNA levels were measured at the Advanced Centre for Treatment, Research, and Education in Cancer (ACTREC) in Mumbai. Findings: Total nicotine content ranged from 0.45 to 35.1 mg/g across products. The unprotonated nicotine fraction contributed 0.1-100% of the total nicotine content. The carcinogenic TSNA levels ranged 0.06-76 ug/g for N'-nitrosonornicotine (NNN), 0.02-19.2 ug/g for 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), and 0.01-6.51 ug/g for 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL). Consistent with our previous study, we observed substantial variations across different brands of the same product type. Interpretation: This is the most extensive and the first within-country study to report brand-specific nicotine and TSNA levels in SLT products marketed in Mumbai, India. Our results show that levels of these constituents remain extremely variable across Indian SLT and are strikingly high in many products. Enhanced public education and continued efforts to reduce SLT use prevalence in India are critical for reducing the global burden of SLT-associated morbidity and mortality. Regulation of nicotine and TSNA levels in SLT products should be considered. Funding: This work was supported by the National Institutes of Health (USA) grant R01-TW010651 and, in part, by grants R01-CA180880 and R50-CA211256. The LC-MS/MS analysis was supported in part by XII Plan project funding from the Department of Atomic Energy, Government of India.

2.
Sci Rep ; 11(1): 20007, 2021 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-34625573

RESUMO

Biomarkers of exposure to harmful tobacco constituents are key tools for identifying individuals at risk and developing interventions and tobacco control measures. However, tobacco biomarker studies are scarce in many parts of the world with high prevalence of tobacco use. Our goal was to establish a robust method for simultaneous analysis of urinary total 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), N'-nitrosonornicotine (NNN), and cotinine at the Advanced Centre for Treatment, Research and Education in Cancer (ACTREC) in Mumbai, India. These biomarkers are validated measures of exposure to the carcinogenic tobacco nitrosamines 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and NNN and the addictive alkaloid nicotine, respectively. The established method is characterized by excellent accuracy, linearity, and precision, and was successfully applied to the analysis of 15 smokeless tobacco (SLT) users and 15 non-users of tobacco recruited in Mumbai. This is the first report of establishment of such procedure in a laboratory in India, which offers the first in-country capacity for research on tobacco carcinogenesis in Indian SLT users.


Assuntos
Biomarcadores/urina , Carcinógenos/análise , Uso de Tabaco/efeitos adversos , Cromatografia Líquida/métodos , Cotinina/urina , Humanos , Nitrosaminas/urina , Espectrometria de Massas em Tandem/métodos , Produtos do Tabaco/análise
3.
Tob Regul Sci ; 6(5): 331-335, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34676280

RESUMO

OBJECTIVES: Gutka is industrially manufactured in India and some Indian states have instituted bans on the sale of manufactured gutka as a public health initiative. We explored whether gutka was still available for purchase after the ban and also sought to observe methods of ban circumvention. METHODS: We visited 5 different markets at different locations separated by at least 15-20 km around the Mumbai Metropolitan Region (MMR) area, consisting of Mumbai and its satellite towns in Maharashtra, India during August- September, 2019. In each location, purveyors were queried as to the availability of gutka. RESULTS: Tobacco purchases were made in 5 locations/sections of MMR. At all markets, banned gutka was not displayed , and could only be purchased after requesting from the shopkeeper. Three methods of ban circumvention were observed: (1) packages marked 'export only'; (2) use of twin packaging in which pan masala and tobacco are sold together for immediate mixing to create gutka; and, (3) non-descript packaging without mention of 'gutka'. CONCLUSIONS: Although not readily displayed in shops, gutka is readily available in MMR, despite a statewide ban in Maharashtra. Marketers have used multiple methods to circumvent the statewide gutka ban.

4.
J Org Chem ; 81(17): 7574-7583, 2016 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-27494613

RESUMO

Guanylhydrazones have been known for a long time and have wide applications in organic synthesis, medicinal chemistry, and material science; however, little attention has been paid toward their electronic and structural properties. Quantum chemical analysis on several therapeutically important guanylhydrazones indicated that all of them prefer the azine tautomeric state (by about 3-12 kcal/mol). A set of simple and conjugated azines were designed using quantum chemical methods, whose tautomeric preference toward the azine tautomer is in the range of 3-8 kcal/mol. Twenty new azines were synthesized and isolated in their neutral state. Variable temperature NMR study suggests existence of the azine tautomer even at higher temperatures with no traces of the hydrazone tautomer. The crystal structures of two representative compounds confirmed that the title compounds prefer to exist in their azine tautomeric form.

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