Browsing by Author "Venugopal, K"

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    Aggregation induced Raman scattering of squaraine dye: Implementation in diagnosis of cervical cancer dysplasia by SERS imaging
    (BIOSENSORS & BIOELECTRONICS, 2015) Narayanan, N; Karunakaran, V; Paul, W; Venugopal, K; Sujathan, K; Maiti, KK
    The extent of squaraine dye aggregation that reflects on surface enhanced Raman signal scattering (SERS) intensity upon adsorption on nano-roughened gold surface has been investigated. Here we have synthesized a serious of six squaraine dyes consisting of two different electron donor moiety i.e. 1,1,2-trimethyl-1H-benzo[elindole and 2-methylbenzo[d]thiazole which modulates the chemisorptions and hydrophobicity being designated as SQ1, SQ2, SQ3, SQ4, SQ5 and SQ6. Interestingly, SQ2 (mono lipoic acid appended), SQ5 and SQ6 (conjugated with hexyl and dodecyl side chain) squaraine derivatives having more tendency of aggregation in DMSO-water mixed solvent showed significant increase of Raman scattering in the fingerprint region when chemisorbed on spherical gold nanoparticles. Two sets of SERS nanotags were prepared with colloidal gold nanoparticle (Au-NPs size: 40 nm) by incorporating Raman reporters SQ2 and SQ5 followed by thiolated PEG encapsulation (SH-PEG, SH-PEG-COOH) denoted as AuNPs-SQ2-PEG and AuNPs-SQ5-PEG. Further conjugation of these nanotag with monoclonal antibodies specific to over expressed receptors, EGFR and p16/Ki-67 in cervical cancer cell, HeLa showed prominent SERS mapping intensity and selectivity towards cell surface and nucleus. The fast and accurate recognition obtained by antibody triggered SERS-nanotag has been compared with conventional time consuming immunocytochemistry technique which prompted us to extend further investigation using real patient cervical smear sample for a non-invasive, ultrafast and accurate diagnosis. (C) 2015 Elsevier B.V. All rights reserved.
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    Prevalence of coronary artery disease and coronary risk factors in Kerala, South India: A population survey - Design and methods
    (Indian Heart Journal, 2013) Zachariah, G; Harikrishnan, S; Krishnan, MN; Mohanan, PP; Sanjay, G; Venugopal, K; Thankappan, KR
    BACKGROUND:There is paucity of reliable contemporary data on prevalence of coronary artery disease (CAD) and risk factors in Indians. Only a few studies on prevalence of CAD have been conducted in Kerala, a Southern Indian state. The main objective of the Cardiological Society of India Kerala Chapter Coronary Artery Disease and Its Risk Factors Prevalence Study (CSI Kerala CRP Study) was to determine the prevalence of CAD and risk factors of CAD in men and women aged 20-79 years in urban and rural settings of three geographical areas of Kerala.METHODS: The design of the study was cross-sectional population survey. We estimated the sample size based on an anticipated prevalence of 7.4% of CAD for rural and 11% for urban Kerala. The derived sample sizes for rural and urban areas were 3000 and 2400, respectively. The urban areas for sampling constituted one ward each from three municipal corporations at different parts of the state. The rural sample was drawn from two panchayats each in the same districts as the urban sample. One adult from each household in the age group of 20-59 years was selected using Kish method. All subjects between 60 and 79 years were included from each household. A detailed questionnaire was administered to assess the risk factors, history of CAD, family history, educational status, socioeconomic status, dietary habits, physical activity and treatment for CAD; anthropometric measurements, blood pressure, electrocardiogram and fasting blood levels of glucose and lipids were recorded.
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    Prevalence of Coronary Artery Disease and its Risk Factors in Kerala, South India: a Community-based Cross-sectional Study
    (BMC Cardiovascular Disorders, 2016-02) Krishnan, MN; Zachariah, G; Venugopal, K; Mohanan, PP; Harikrishnan, S; Sanjay, G; Jeyaseelan, L; Thankappan, KR
    Background: There are no recent data on prevalence of coronary artery disease (CAD) in Indians. The last community based study from Kerala, the most advanced Indian state in epidemiological transition, was in 1993 that reported 1.4 % definite CAD prevalence. We studied the prevalence of CAD and its risk factors among adults in Kerala. Methods: In a community-based cross sectional study, we selected 5167 adults (mean age 51 years, men 40.1 %) using a multistage cluster sampling method. Information on socio-demographics, smoking, alcohol use, physical activity, dietary habits and personal history of hypertension, diabetes, and CAD was collected using a structured interview schedule. Anthropometry, blood pressure, electrocardiogram, and biochemical investigations were done using standard protocols. CAD and its risk factors were defined using standard criteria. Comparisons of age adjusted prevalence were done using two tailed proportion tests. Results: The overall age-adjusted prevalence of definite CAD was 3.5 %: men 4.8 %, women 2.6 % (p < 0.001). Prevalence of any CAD was 12.5 %: men 9.8 %, women 14.3 % (p < 0.001). There was no difference in definite CAD between urban and rural population. Physical inactivity was reported by 17.5 and 18 % reported family history of CAD. Other CAD risk factors detected in the study were: overweight or obese 59 %, abdominal obesity 57 %, hypertension 28 %, diabetes 15 %, high total cholesterol 52 % and low level of high density lipoprotein cholesterol 39 %. Current smoking was reported only be men (28 %). Conclusion: The prevalence of definite CAD in Kerala increased nearly three times since 1993 without any difference in urban and rural areas. Most risk factors of CAD were highly prevalent in the state. Both population and individual level approaches are warranted to address the high level of CAD risk factors to reduce the increasing prevalence of CAD in this population.