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Rajesh Kumar

Bio: Rajesh Kumar is an academic researcher from Himachal Pradesh University. The author has contributed to research in topics: Medicine & Materials science. The author has an hindex of 149, co-authored 4439 publications receiving 140830 citations. Previous affiliations of Rajesh Kumar include Guru Nanak Dev University & Intuitive Surgical.


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Journal ArticleDOI
01 Apr 2018-Heart
TL;DR: External validations of the NL-IHRS and FC-IhRS suggest that regionally recalibrated versions of both can be useful for estimating CVD risk across a diverse range of community-based populations.
Abstract: Objective To evaluate the performance of the non-laboratory INTERHEART risk score (NL-IHRS) to predict incident cardiovascular disease (CVD) across seven major geographic regions of the world. The secondary objective was to evaluate the performance of the fasting cholesterol-based IHRS (FC-IHRS). Methods Using measures of discrimination and calibration, we tested the performance of the NL-IHRS (n=100 475) and FC-IHRS (n=107 863) for predicting incident CVD in a community-based, prospective study across seven geographic regions: South Asia, China, Southeast Asia, Middle East, Europe/North America, South America and Africa. CVD was defined as the composite of cardiovascular death, myocardial infarction, stroke, heart failure or coronary revascularisation. Results Mean age of the study population was 50.53 (SD 9.79) years and mean follow-up was 4.89 (SD 2.24) years. The NL-IHRS had moderate to good discrimination for incident CVD across geographic regions (concordance statistic (C-statistic) ranging from 0.64 to 0.74), although recalibration was necessary in all regions, which improved its performance in the overall cohort (increase in C-statistic from 0.69 to 0.72, p Conclusions External validations of the NL-IHRS and FC-IHRS suggest that regionally recalibrated versions of both can be useful for estimating CVD risk across a diverse range of community-based populations. CVD prediction using a non-laboratory score can provide similar accuracy to laboratory-based methods.

50 citations

Journal ArticleDOI
TL;DR: This work has shown that activation, proliferation and migration of melanoblasts from the outer root sheath of hair follicles, or melanocytes from the border area of vitiligo lesions, into the depigmented epidermis plays a crucial role during repigmentation in Vitiligo.
Abstract: Background Vitiligo is characterized by the loss of functional melanocytes from the epidermis. Repigmentation in vitiligo is initiated by activation, proliferation and migration of melanoblasts from the outer root sheath of hair follicles, or melanocytes from the border area of vitiligo lesions, into the depigmented epidermis. Cell migration plays a crucial role during repigmentation in vitiligo. Objectives To investigate the role of matrix metalloproteinases (MMPs) and their transcription factor Ets-1 in vitiligo. Methods Skin biopsies were taken from 15 patients with vitiligo and six controls to culture melanocytes from clinically active perilesional and normal skin. Expression of MMP-1, MMP-2, MMP-9 and Ets-1 was examined by reverse transcriptase-polymerase chain reaction analysis. Expression of Ets-1 was also confirmed with Western blot analysis. Activity of MMP-2 and MMP-9 was assessed using gelatin zymography. Results The activity of MMP-2 and MMP-9 was significantly lower in patients with vitiligo compared with the controls. The expression of MMP-2 and MMP-9 was also significantly lower in patients with vitiligo. There was no expression of Ets-1 transcription factor at either the transcriptional or translational level in melanocytes cultured from patients with vitiligo. Conclusion The absence of a basal level of expression of Ets-1 significantly decreases the expression and activity of MMP-2 and MMP-9. Significant decreases in MMP-2 and MMP-9 activity could possibly reduce the migration of melanocyte precursors (melanoblasts) from the outer root sheath of hair follicles or migration of melanocytes from the border of vitiligo lesions into clinically depigmented epidermis which is crucial to the repigmentation of vitiliginous skin.

50 citations

Journal ArticleDOI
TL;DR: Multiple brain regions showed both higher axial and radial diffusivity, indicative of loss of tissue integrity with a combination of myelin and axonal injury, including basal ganglia, bed nucleus, and limbic, occipital, and temporal areas.
Abstract: Brain injury underlying the state-related loss of ventilatory drive, autonomic, cognitive, and affective deficits in congenital central hypoventilation syndrome (CCHS) patients appears throughout the brain, as demonstrated by magnetic resonance (MR) T2 relaxometry and mean diffusivity studies. However, neither MR measure is optimal to describe types of axonal injury essential for assessing neural interactions responsible for CCHS characteristics. To evaluate axonal integrity and partition the nature of tissue damage (axonal vs. myelin injury) in CCHS, we measured water diffusion parallel (axial diffusivity) and perpendicular (radial diffusivity) to rostral brain fibers, indicative of axonal and myelin changes, respectively, with diffusion tensor imaging (DTI). We performed DTI in 12 CCHS (age 18.5 ± 4.9 years, 7 male) and 30 control (17.7 ± 4.6 years, 18 male) subjects, using a 3.0-Tesla MR imaging scanner. Axial and radial diffusivity maps were calculated, spatially normalized, smoothed, and compared between groups (analysis of covariance; covariates, age and gender). Significantly increased radial diffusivity, primarily indicative of myelin injury, emerged in fibers of the corona radiata, internal capsule, corpus callosum, hippocampus through the fornix, cingulum bundle, and temporal and parietal lobes. Increased axial diffusivity, suggestive of axonal injury, appeared in fibers of the internal capsule, thalamus, corona radiata, and occipital and temporal lobes. Multiple brain regions showed both higher axial and radial diffusivity, indicative of loss of tissue integrity with a combination of myelin and axonal injury, including basal ganglia, bed nucleus, and limbic, occipital, and temporal areas. The processes underlying injury are unclear, but likely stem from both hypoxic and developmental processes. © 2010 Wiley-Liss, Inc.

50 citations

Journal ArticleDOI
TL;DR: No significant association between arsenic exposure in the workplace and NMSC was detected, although an increased adjusted odd ratio was observed for participants with higher cumulative lifetime workplace exposure to arsenic in dust and fumes compared to referents, and there is evidence for modification of the workplace arsenic–NMSC association by work‐related sunlight exposure in women.
Abstract: Occupational studies show a high risk of lung cancer related to arsenic exposure by inhalation; however, only a few studies, and with conflicting results, previously examined a potential link between arsenic exposure at work and skin cancer. The aim of this study is to assess airborne arsenic exposures at the workplace and to quantify associations with nonmelanoma skin cancer (NMSC). The study sample consists of 618 incident cases of NMSC and 527 hospital-based controls aged 30-79 years from Hungary, Romania and Slovakia. Exposures were evaluated by local experts using occupational histories. Information on host factors and other exposures was collected and used to adjust the associations of interest using multivariable logistic regression. The lifetime prevalence of exposure to work-related arsenic is 23.9% for cases and 15.5% for controls. No significant association between arsenic exposure in the workplace and NMSC was detected, although an increased adjusted odd ratio was observed for participants with higher cumulative lifetime workplace exposure to arsenic in dust and fumes compared to referents [odds ratios (OR) = 1.94, 95% confidence interval (CI) = 0.76-4.95]. There is evidence for modification of the workplace arsenic-NMSC association by work-related sunlight exposure in women, with a markedly increased adjusted OR in the presence of workplace sunlight exposure (OR = 10.22, 95% CI = 2.48-42.07). Workplace coexposure to arsenic and sunlight may thus pose an increased risk of NMSC.

50 citations

Journal ArticleDOI
TL;DR: Prevalence of asthma and its association with environmental tobacco smoke exposure were examined among adolescent schoolchildren in Chandigarh, India and ETS was positively associated with prevalence of all the respiratory symptoms.
Abstract: Prevalence of asthma and its association with environmental tobacco smoke (ETS) exposure were examined among adolescent schoolchildren in Chandigarh, India. Using a previously standardized questionnaire, data from 9090 students in the 9- to 20-year age range were analyzed. There were 4367 (48%) boys, in whom the observed prevalence of asthma was 2.6%. Among 4723 (52%) girls, asthma was present in 90 (1.9%) students. Presence of one or more respiratory symptoms was reported by 31% students. More students with asthma had either parents or other family members smoking at home as compared to nonasthmatics (41% vs. 28%, p<0.0001). The odds ratio for being asthmatic for patients exposed to ETS compared to those not exposed to ETS was 1.78 (95% confidence interval 1.33-2.31). ETS was also positively associated with prevalence of all the respiratory symptoms, with odds ratios varying between 1.6 and 2.25.

50 citations


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08 Dec 2001-BMJ
TL;DR: There is, I think, something ethereal about i —the square root of minus one, which seems an odd beast at that time—an intruder hovering on the edge of reality.
Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

33,785 citations

01 May 1993
TL;DR: Comparing the results to the fastest reported vectorized Cray Y-MP and C90 algorithm shows that the current generation of parallel machines is competitive with conventional vector supercomputers even for small problems.
Abstract: Three parallel algorithms for classical molecular dynamics are presented. The first assigns each processor a fixed subset of atoms; the second assigns each a fixed subset of inter-atomic forces to compute; the third assigns each a fixed spatial region. The algorithms are suitable for molecular dynamics models which can be difficult to parallelize efficiently—those with short-range forces where the neighbors of each atom change rapidly. They can be implemented on any distributed-memory parallel machine which allows for message-passing of data between independently executing processors. The algorithms are tested on a standard Lennard-Jones benchmark problem for system sizes ranging from 500 to 100,000,000 atoms on several parallel supercomputers--the nCUBE 2, Intel iPSC/860 and Paragon, and Cray T3D. Comparing the results to the fastest reported vectorized Cray Y-MP and C90 algorithm shows that the current generation of parallel machines is competitive with conventional vector supercomputers even for small problems. For large problems, the spatial algorithm achieves parallel efficiencies of 90% and a 1840-node Intel Paragon performs up to 165 faster than a single Cray C9O processor. Trade-offs between the three algorithms and guidelines for adapting them to more complex molecular dynamics simulations are also discussed.

29,323 citations

Journal ArticleDOI
TL;DR: It is recommended that spirometry is required for the clinical diagnosis of COPD to avoid misdiagnosis and to ensure proper evaluation of severity of airflow limitation.
Abstract: Chronic obstructive pulmonary disease (COPD) remains a major public health problem. It is the fourth leading cause of chronic morbidity and mortality in the United States, and is projected to rank fifth in 2020 in burden of disease worldwide, according to a study published by the World Bank/World Health Organization. Yet, COPD remains relatively unknown or ignored by the public as well as public health and government officials. In 1998, in an effort to bring more attention to COPD, its management, and its prevention, a committed group of scientists encouraged the U.S. National Heart, Lung, and Blood Institute and the World Health Organization to form the Global Initiative for Chronic Obstructive Lung Disease (GOLD). Among the important objectives of GOLD are to increase awareness of COPD and to help the millions of people who suffer from this disease and die prematurely of it or its complications. The first step in the GOLD program was to prepare a consensus report, Global Strategy for the Diagnosis, Management, and Prevention of COPD, published in 2001. The present, newly revised document follows the same format as the original consensus report, but has been updated to reflect the many publications on COPD that have appeared. GOLD national leaders, a network of international experts, have initiated investigations of the causes and prevalence of COPD in their countries, and developed innovative approaches for the dissemination and implementation of COPD management guidelines. We appreciate the enormous amount of work the GOLD national leaders have done on behalf of their patients with COPD. Despite the achievements in the 5 years since the GOLD report was originally published, considerable additional work is ahead of us if we are to control this major public health problem. The GOLD initiative will continue to bring COPD to the attention of governments, public health officials, health care workers, and the general public, but a concerted effort by all involved in health care will be necessary.

17,023 citations

01 Jan 2016
TL;DR: The using multivariate statistics is universally compatible with any devices to read, allowing you to get the most less latency time to download any of the authors' books like this one.
Abstract: Thank you for downloading using multivariate statistics. As you may know, people have look hundreds times for their favorite novels like this using multivariate statistics, but end up in infectious downloads. Rather than reading a good book with a cup of tea in the afternoon, instead they juggled with some harmful bugs inside their laptop. using multivariate statistics is available in our digital library an online access to it is set as public so you can download it instantly. Our books collection saves in multiple locations, allowing you to get the most less latency time to download any of our books like this one. Merely said, the using multivariate statistics is universally compatible with any devices to read.

14,604 citations