Publications by authors named "Nuzhat R Siddiqui"

The primary aim of the study was to determine whether plasma concentrations of homocysteine (Hcy), a functional indicator of methyl donor nutrients, are associated with altered risk of higher grades of cervical intraepithelial neoplasia (CIN 2+) and the degree of methylation in long interspersed nucleotide elements (LINE-1s) of peripheral blood mononuclear cells, a potential biomarker of CIN 2+ in a population of women exposed to the United States folic acid fortification program. The secondary aim was to assess the determinants of plasma Hcy in the same population. The study included 457 women diagnosed with either CIN 2+ (cases, n = 132) or ≤ CIN 1 (non-cases, n = 325).

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Background: Studies in populations unexposed to folic acid (FA) fortification have demonstrated that MTHFR C677T polymorphism is associated with increased risk of higher grades of cervical intraepithelial neoplasia (CIN 2+). However, it is unknown whether exposure to higher folate as a result of the FA fortification program has altered the association between MTHFR C677T and risk of CIN, or the mechanisms involved with such alterations. The current study investigated the following in a FA fortified population: 1) The association between MTHFR C677T polymorphism and risk of CIN 2+; 2) The modifying effects of plasma folate concentrations on this association; and 3) The modifying effects of plasma folate on the association between the polymorphism and degree of methylation of long interspersed nucleotide elements (L1s), in peripheral blood mononuclear cell (PBMC) DNA, a documented biomarker of CIN risk.

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We previously reported that a higher degree of methylation of CpG sites in the promoter (positions 31, 37, 43, 52, and 58) and enhancer site 7862 of human papillomavirus (HPV) 16 was associated with a lower likelihood of being diagnosed with HPV 16-associated CIN 2+. The purpose of this study was to replicate our previous findings and, in addition, to evaluate the influence of plasma concentrations of folate and vitamin B12 on the degree of HPV 16 methylation (HPV 16m). The study included 315 HPV 16-positive women diagnosed with either CIN 2+ or ≤CIN 1.

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Objective: The objective of the study was to evaluate LINE-1 methylation as an intermediate biomarker for the effect of folate and vitamin B12 on the occurrence of higher grades of cervical intraepithelial neoplasia (CIN ≥ 2).

Methods: This study included 376 women who tested positive for high-risk human papillomaviruses and were diagnosed with CIN ≥ 2 (cases) or CIN ≤ 1 (non-cases). CIN ≥ 2 (yes/no) was the dependent variable in logistic regression models that specified the degree of LINE-1 methylation of peripheral blood mononuclear cells (PBMCs) and of exfoliated cervical cells (CCs) as the independent predictors of primary interest.

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African Americans are more susceptible to develop insulin resistance, obesity, Type 2 Diabetes, and coronary heart disease (CHD), and systemic inflammation is central to the pathophysiology of these chronic diseases. African Americans are also more likely to contract H. pylori (cagA) infections during their childhood.

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