Publications by authors named "Harishankar M"

Background: Oral squamous cell carcinoma (OSCC) is a malignant oral cavity neoplasm that affects many people, especially in developing countries. Despite several advances that have been made in diagnosis and treatment, the morbidity and mortality rates due to OSCC remain high. Accumulating evidence indicates that aberrant activation of cellular signaling pathways, such as the Notch, Wnt and Hedgehog pathways, occurs during the development and metastasis of OSCC.

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Article Synopsis
  • - Tuberculosis (TB) is a significant global health threat, with various studies indicating that genetic factors in different populations can influence an individual's susceptibility or resistance to the disease.
  • - Research has identified specific genetic markers, such as variations in HLA and non-HLA genes (e.g., KIR, TLRs), which play a role in immune responses and TB development.
  • - Recent meta-analyses and genome-wide association studies (GWAS) have found certain HLA alleles and other genetic variants associated with TB susceptibility, highlighting the influence of ethnicity on these associations.
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1,25-dihydroxyvitaminD [1,25(OH)D] modulates both the innate and adaptive immunity in tuberculosis. We explored the effect of 1,25(OH)D on cytolytic molecules like perforin, granulysin, and granzyme-B in T-cells and natural killer cells during M. tuberculosis (Mtb) infection.

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Hypoxia, a condition of low oxygen tension in tissues, has emerged as a crucial factor in tumor pathophysiology. Hypoxic microenvironment gives rise to altered cellular metabolism and triggers varied molecular responses. These responses promote tumor progression and confer radiation resistance and chemo resistance to tumors.

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  • Somatic stem cells in adults help maintain organ function but can't regenerate major cell loss, especially in limited-replicating cells like neurons and heart cells.
  • The concept of inducing pluripotency in somatic cells emerged to enhance their regenerative abilities, leading to Yamanaka's breakthrough in 2006, which identified 4 crucial genes (OCT-4, SOX-2, KLF-4, c-MYC).
  • This study reviews methods for inducing pluripotency, their differentiation applications, and the current status of induced pluripotent stem cells (iPSCs) in clinical trials, aiming to guide researchers in their clinical applications.
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Background: Genetic factors play an important role in the development of disease susceptibility or protection. Cytokine gene polymorphisms are reported to be associated with altered levels of cytokine production that can impact disease progression in HIV and TB.

Objective: In this study, we studied IL-10 -592(C/A) and TGF-β -509 (C/T) promoter polymorphisms to understand their role in susceptibility or resistance to HIV and TB in a South Indian population.

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Introduction: Oral verrucous carcinoma is a special form of well-differentiated squamous cell carcinoma which possesses specific clinical, morphologic and cytokinetic features that differ from other types of oral cancers and hence diagnosis requires immense experience in histopathology. Hence it is certainly important to distinguish such a lesion from other oral tumors as treatment strategies vary widely between them.

Objective: In search of a critical diagnostic marker in distinguishing oral verrucous carcinoma from oral squamous cell carcinoma, Notch4 receptor, one of the key regulatory molecules of the Notch signaling family has been aberrantly activated in the progression of several types of tumors.

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Purpose: We studied the effect of 1,25(OH)D (vitamin D) on intracellular chemokine-positive T-cell subsets in whole blood cultures of healthy controls and patients with pulmonary tuberculosis.

Methods: Genotyping was performed by the polymerase chain reaction-restriction fragment length polymorphism method. The regulatory role of the Cdx2 and 3'UTR TaqI gene variants on chemokine-positive T-cell subsets was studied from culture filtrate antigen stimulated with or without vitamin D treated whole blood cultures of 60 healthy controls and 50 patients with pulmonary tuberculosis.

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Vitamin D receptor (VDR) gene variants have been shown to be regulating the immune response in tuberculosis. We studied the regulatory role of VDR promoter Cdx-2 and 3'UTR TaqI gene variants on chemokine levels from culture filtrate antigen (CFA) stimulated with or without 1,25(OH)2D3 treated peripheral blood mononuclear cells of 50 pulmonary tuberculosis patients (PTB) and 51 normal healthy controls (HCs). In CFA with 1,25(OH)2D3 treated cultures, the MIP-1α, MIP-1β, RANTES levels were significantly decreased in Cdx-2 AA genotype compared to GG genotype, while a significantly increased MIG level was observed in Cdx-2 AA genotype (p<0.

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1,25-Dihydroxyvitamin D3 [1,25(OH)2D3] the active form of vitamin D3 acts as an immunomodulator in various immune cells. The present study is aimed to study the effect of 1,25(OH)2D3 on chemokine levels and regulatory T-cells in 51 healthy controls (HCs) and 50 pulmonary tuberculosis (PTB) patients. Peripheral blood mononuclear cells were cultured with culture filtrate antigen (CFA) of Mycobacterium tuberculosis in the presence or absence of 1,25(OH)2D3 at 10(-7) M concentration for 72 h and the percentage positive regulatory T-cell subsets were studied using flow cytometry.

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Micronucleus (MN) assay was performed on the exfoliated urothelial cells to detect the genotoxic effects of the anti-hyperglycemic drugs, metformin and glimepiride in T2DM patients and to use it as a biomarker for DNA damage by assessing the frequency of micronuclei in the exfoliated urothelial cells. A total of 201 subjects (147 T2DM patients & 54 Normal cases) were selected from diverse age groups (25-75 years) and the mean MN frequency was examined per 1000 cells in all the subjects. Relative to the control group (5.

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Tuberculosis (TB) is a major global health problem and often coincides with vitamin D deficiency. High doses of vitamin D were widely used to treat TB during the pre-antibiotic era. Vitamin D exerts its action through vitamin D receptor (VDR), and VDR gene polymorphisms are associated with susceptibility or resistance to tuberculosis as well as sputum smear and culture conversion during anti-TB treatment.

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1,25-dihydroxy vitamin D3 (1,25(OH)2D3) is a potent immuno-modulator which induces LL-37, the active peptide of cathelicidin, and restricts the growth of Mycobacterium tuberculosis (Mtb) in human macrophages. In the present study, we investigated the effect of 1,25(OH)2D3 on cathelicidin antimicrobial peptide (CAMP) expression in healthy controls (HCs) and pulmonary tuberculosis (PTB) patients. Peripheral blood mononuclear cells (PBMCs) from 50 HCs and 35 PTB patients were cultured for 72 h either with Mtb alone or Mtb with 1,25(OH)2D3 at 10(-7) M concentration.

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1,25-Dihydroxy vitamin D3 [1,25(OH)2D3] is a potent immunomodulator and regulates various immune responses to Mycobacterium tuberculosis (Mtb). The present study aimed to understand the effect of 1,25(OH)2D3 on pro-inflammatory cytokine response to Mtb antigen. Peripheral blood mononuclear cells from 42 healthy controls (HCs) and 42 pulmonary tuberculosis (PTB) patients were cultured with culture filtrate antigen (CFA) of Mtb with and without 1,25(OH)2D3 at 10(-7)M concentration for 72 h.

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Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a cytokine that is essential for growth and development of progenitors of granulocytes and monocytes/macrophages. In this study, we report molecular cloning, sequencing and characterization of GM-CSF from Indian water buffalo, Bubalus bubalis. In addition, we performed sequence and structural analysis for buffalo GM-CSF.

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Chlorpyrifos (CP) is the most commonly used pesticide throughout the world. Its widespread use in agriculture and its potential toxicity to humans from ingestion of CP contaminated food have raised concerns about its risk to health. Human intestinal microflora has the ability to degrade pesticides, but the exact mechanisms involved and the metabolite end-products formed are not well understood.

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1,25 Dihydroxy vitamin D(3) (vitamin D(3)) is an immunomodulator and its deficiency has been associated with susceptibility to tuberculosis. We have studied the immunoregulatory role of vitamin D(3) on various chemokine expression in pulmonary tuberculosis. Peripheral blood mononuclear cells obtained from 21 pulmonary tuberculosis (PTB) patients and 24 healthy controls (HCs) were cultured for 48 h with culture filtrate antigen (CFA) of Mycobacterium tuberculosis with or without vitamin D(3) at a concentration 1 × 10(-7)M.

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Full-length cDNA (435 bp) of the interleukin-3(IL-3) gene of the Indian water buffalo was amplified by reverse transcriptase-polymerase chain reaction and sequenced. This sequence had 96% nucleotide identity and 92% amino acid identity with bovine IL-3. There are 10 amino acid substitutions in buffalo compared with that of bovine.

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Toll-like receptors (TLRs) are pattern recognition receptors and play an important role in innate immunity. Changes in TLRs and signaling molecules that result from polymorphisms are often associated with susceptibility to various infectious diseases. In the present study, we investigated whether variants in the TLR-1 1805T/G (Ile602Ser), TLR-2 2258G/A (Arg753Gln), TLR-4 896A/G (Asp299Gly), TLR-4 1196C/T (Thr399Ile), TLR-6 745C/T (Ser249Pro), TIRAP 975C/T (Ser180Leu) genes and TLR-9 promoter region polymorphisms at positions -1237C/T and -1486C/T are associated with susceptibility or resistance to pulmonary tuberculosis (PTB).

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We investigated whether IFN-gamma gene +874(A/T) polymorphism influences intracellular interferon gamma expression in T-cell subsets of normal healthy subjects (NHS) and pulmonary tuberculosis patients (PTB). Peripheral blood mononuclear cells were stimulated with live Mycobacterium tuberculosis (MTB) and the intracellular IFN-gamma expression was studied using flow cytometry. Genotyping of IFN-gamma gene +874(A/T) was done using allele specific polymerase chain reaction.

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Introduction: Vitamin D(3), which exerts its effect through vitamin D receptor (VDR), is known for its potent immunomodulatory activities. Associations between low serum vitamin D(3) levels and increased risk of tuberculosis have been reported.

Study Subjects And Methods: Plasma 1,25 dihydroxy vitamin D(3) levels (1,25(OH)(2) D(3)) and ex vivo levels of VDR protein from peripheral blood mononuclear cells were studied in 65 pulmonary tuberculosis (PTB) patients and 60 normal healthy subjects (NHS) using enzyme-linked immunosorbent assay-based methods.

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Dendritic-cell-specific intercellular adhesion molecule-3 (ICAM-3)-grabbing non-integrin (DC-SIGN), a pattern recognition receptor, is associated with immune functions and is also exploited by HIV-1 and Mycobacterium tuberculosis as a part of their immune evasion strategy. In the present study we investigated whether variants in the DC-SIGN encoding CD209 gene are associated with susceptibility to or protection against HIV-1 infection as well as development of tuberculosis (TB) among HIV-1 infected south Indian patients. CD209 gene variants in the promoter region (-336 and -139), in the intron and 3'-untranslated regions (In2+11 and 2281) were studied using polymerase chain reaction-based genotyping methods in 131 HIV patients without TB (HIV+TB-) and 107 HIV patients with TB (HIV+TB+), 107 HIV negative pulmonary TB patients (HIV-PTB+) and 157 healthy controls.

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Polymorphisms in the cytokine genes are known to influence cytokine levels and may be associated with outcome of infections. We investigated the polymorphisms in the cytokine genes namely IFN-gamma (+874 and +5644), IL-2 (-330 and +160), IL-4 (VNTR), IL-6 (-174), IL-10 (-1082 and -819) and IL-12B (+1188) in 188 normal healthy subjects (NHS) and 166 pulmonary tuberculosis patients (PTB) using polymerase chain reaction-based methods. To study the influence of cytokine gene polymorphisms on cytokine levels, phytohaemagglutinin and culture filtrate antigen of Mycobacterium tuberculosis-induced cytokine levels were measured by ELISA from 72-h-old peripheral blood mononuclear cell culture supernatants.

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Vitamin D receptor (VDR) gene variants are associated with differential susceptibility or resistance to tuberculosis in different ethnic groups. We investigated the polymorphisms in the 5' regulatory region of VDR gene in 206 normal healthy subjects and 166 patients with pulmonary tuberculosis from south India. Cdx-2 polymorphism was studied by polymerase chain reaction (PCR) with allele-specific primers, while genotyping of A1012G was done by PCR-based restriction fragment length polymorphism.

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Interleukin-18 (IL-18) plays a vital role in both innate and acquired immunity. We analysed polymorphisms at -607(C/A) and -137(G/A) in the promoter region of IL-18 gene by allele-specific polymerase chain reaction in normal healthy subjects (n = 173) and patients with pulmonary tuberculosis (n = 165). Allele, genotype and haplotype frequencies did not differ significantly between normal healthy subjects and patients.

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