Search

Your search keyword '"A. Ramachandran"' showing total 519 results
Start Over Author "A. Ramachandran" Journal scientific reports
519 results on '"A. Ramachandran"'

10. Author Correction: Contribution of infection and vaccination to population-level seroprevalence through two COVID waves in Tamil Nadu, India

Author

Selvavinayagam, T. S., Somasundaram, Anavarathan, Selvam, Jerard Maria, Sampath, P., Vijayalakshmi, V., Kumar, C. Ajith Brabhu, Subramaniam, Sudharshini, Kumarasamy, Parthipan, Raju, S., Avudaiselvi, R., Prakash, V., Yogananth, N., Subramanian, Gurunathan, Roshini, A., Dhiliban, D. N., Imad, Sofia, Tandel, Vaidehi, Parasa, Rajeswari, Sachdeva, Stuti, Ramachandran, Sabareesh, and Malani, Anup

Published
2024
Full Text
View/download PDF

11. Contribution of infection and vaccination to population-level seroprevalence through two COVID waves in Tamil Nadu, India

Author

Selvavinayagam, T. S., Somasundaram, Anavarathan, Selvam, Jerard Maria, Sampath, P., Vijayalakshmi, V., Kumar, C. Ajith Brabhu, Subramaniam, Sudharshini, Kumarasamy, Parthipan, Raju, S., Avudaiselvi, R., Prakash, V., Yogananth, N., Subramanian, Gurunathan, Roshini, A., Dhiliban, D. N., Imad, Sofia, Tandel, Vaidehi, Parasa, Rajeswari, Sachdeva, Stuti, Ramachandran, Sabareesh, and Malani, Anup

Published
2024
Full Text
View/download PDF

12. Cerebral small vessel disease burden is associated with decreased abundance of gut Barnesiella intestinihominis bacterium in the Framingham Heart Study

Author

Fongang, Bernard, Satizabal, Claudia, Kautz, Tiffany F, Wadop, Yannick N, Muhammad, Jazmyn AS, Vasquez, Erin, Mathews, Julia, Gireud-Goss, Monica, Saklad, Amy R, Himali, Jayandra, Beiser, Alexa, Cavazos, Jose E, Mahaney, Michael C, Maestre, Gladys, DeCarli, Charles, Shipp, Eric L, Vasan, Ramachandran S, and Seshadri, Sudha

Subjects
Microbiology, Biological Sciences, Acquired Cognitive Impairment, Neurosciences, Dementia, Brain Disorders, Aging, Clinical Research, Neurological, Humans, Cross-Sectional Studies, Dysbiosis, RNA, Ribosomal, 16S, Bacteria, AMP-Activated Protein Kinases, Cerebral Small Vessel Diseases
Abstract

A bidirectional communication exists between the brain and the gut, in which the gut microbiota influences cognitive function and vice-versa. Gut dysbiosis has been linked to several diseases, including Alzheimer's disease and related dementias (ADRD). However, the relationship between gut dysbiosis and markers of cerebral small vessel disease (cSVD), a major contributor to ADRD, is unknown. In this cross-sectional study, we examined the connection between the gut microbiome, cognitive, and neuroimaging markers of cSVD in the Framingham Heart Study (FHS). Markers of cSVD included white matter hyperintensities (WMH), peak width of skeletonized mean diffusivity (PSMD), and executive function (EF), estimated as the difference between the trail-making tests B and A. We included 972 FHS participants with MRI scans, neurocognitive measures, and stool samples and quantified the gut microbiota composition using 16S rRNA sequencing. We used multivariable association and differential abundance analyses adjusting for age, sex, BMI, and education level to estimate the association between gut microbiota and WMH, PSMD, and EF measures. Our results suggest an increased abundance of Pseudobutyrivibrio and Ruminococcus genera was associated with lower WMH and PSMD (p values

Published
2023

17. Expression quantitative trait methylation analysis elucidates gene regulatory effects of DNA methylation: the Framingham Heart Study

Author

Keshawarz, Amena, Bui, Helena, Joehanes, Roby, Ma, Jiantao, Liu, Chunyu, Huan, Tianxiao, Hwang, Shih-Jen, Tejada, Brandon, Sooda, Meera, Courchesne, Paul, Munson, Peter J., Demirkale, Cumhur Y., Yao, Chen, Heard-Costa, Nancy L., Pitsillides, Achilleas N., Lin, Honghuang, Liu, Ching-Ti, Wang, Yuxuan, Peloso, Gina M., Lundin, Jessica, Haessler, Jeffrey, Du, Zhaohui, Cho, Michael, Hersh, Craig P., Castaldi, Peter, Raffield, Laura M., Wen, Jia, Li, Yun, Reiner, Alexander P., Feolo, Mike, Sharopova, Nataliya, Vasan, Ramachandran S., DeMeo, Dawn L., Carson, April P., Kooperberg, Charles, and Levy, Daniel

Published
2023
Full Text
View/download PDF

26. Whole genome DNA and RNA sequencing of whole blood elucidates the genetic architecture of gene expression underlying a wide range of diseases

Author

Liu, Chunyu, Joehanes, Roby, Ma, Jiantao, Wang, Yuxuan, Sun, Xianbang, Keshawarz, Amena, Sooda, Meera, Huan, Tianxiao, Hwang, Shih-Jen, Bui, Helena, Tejada, Brandon, Munson, Peter J., Demirkale, Cumhur Y., Heard-Costa, Nancy L., Pitsillides, Achilleas N., Peloso, Gina M., Feolo, Michael, Sharopova, Nataliya, Vasan, Ramachandran S., and Levy, Daniel

Published
2022
Full Text
View/download PDF

35. Selective Connexin43 Inhibition Prevents Isoproterenol-Induced Arrhythmias and Lethality in Muscular Dystrophy Mice

Author

Gonzalez, J Patrick, Ramachandran, Jayalakshmi, Xie, Lai-Hua, Contreras, Jorge E, and Fraidenraich, Diego

Subjects
Medical Physiology, Biomedical and Clinical Sciences, Cardiovascular, Pediatric, Rare Diseases, Muscular Dystrophy, Brain Disorders, Duchenne/ Becker Muscular Dystrophy, Intellectual and Developmental Disabilities (IDD), Heart Disease, Aetiology, 2.1 Biological and endogenous factors, Adolescent, Animals, Arrhythmias, Cardiac, Connexin 43, Disease Models, Animal, Female, Humans, Isoproterenol, Male, Mice, Mice, Inbred C57BL, Mice, Inbred mdx, Muscular Dystrophy, Animal, Muscular Dystrophy, Duchenne, Peptides, Up-Regulation
Abstract

Duchenne muscular dystrophy (DMD) is caused by an X-linked mutation that leads to the absence of dystrophin, resulting in life-threatening arrhythmogenesis and associated heart failure. We targeted the gap junction protein connexin43 (Cx43) responsible for maintaining cardiac conduction. In mild mdx and severe mdx:utr mouse models of DMD, and human DMD tissues, Cx43 was found to be pathologically mislocalized to lateral sides of cardiomyocytes. In addition, overall Cx43 protein levels were markedly increased in mouse and human DMD heart tissues examined. Electrocardiography on isoproterenol challenged mice showed that both models developed arrhythmias and died within 24 hours, while wild-type mice were free of pathology. Administering peptide mimetics to inhibit lateralized Cx43 function prior to challenge protected mdx mice from arrhythmogenesis and death, while mdx:utr mice displayed markedly improved ECG scores. These findings suggest that Cx43 lateralization contributes significantly to DMD arrhythmogenesis and that selective inhibition may provide substantial benefit.

Published
2015

44. Structure and permeability of ion-channels by integrated AFM and waveguide TIRF microscopy.

Author

Ramachandran, Srinivasan, Arce, Fernando Teran, Patel, Nirav R, Quist, Arjan P, Cohen, Daniel A, and Lal, Ratnesh

Subjects
Gap Junctions, Fibroblasts, Animals, Rats, Calcium, Isoquinolines, Lipid Bilayers, Connexin 43, Fluorescent Dyes, Microscopy, Fluorescence, Microscopy, Atomic Force, Structure-Activity Relationship, Biological Transport, Permeability, Porosity, Microscopy, Fluorescence, Atomic Force
Abstract

Membrane ion channels regulate key cellular functions and their activity is dependent on their 3D structure. Atomic force microscopy (AFM) images 3D structure of membrane channels placed on a solid substrate. Solid substrate prevents molecular transport through ion channels thus hindering any direct structure-function relationship analysis. Here we designed a ~70 nm nanopore to suspend a membrane, allowing fluidic access to both sides. We used these nanopores with AFM and total internal reflection fluorescence microscopy (TIRFM) for high resolution imaging and molecular transport measurement. Significantly, membranes over the nanopore were stable for repeated AFM imaging. We studied structure-activity relationship of gap junction hemichannels reconstituted in lipid bilayers. Individual hemichannels in the membrane overlying the nanopore were resolved and transport of hemichannel-permeant LY dye was visualized when the hemichannel was opened by lowering calcium in the medium. This integrated technique will allow direct structure-permeability relationship of many ion channels and receptors.

Published
2014

45. High performance, LED powered, waveguide based total internal reflection microscopy

Author

Ramachandran, Srinivasan, Cohen, Daniel A, Quist, Arjan P, and Lal, Ratnesh

Subjects
Quantum Physics, Physical Sciences, Animals, Cell Line, Tumor, Mice, Microscopy, Fluorescence
Abstract

Total internal reflection fluorescence (TIRF) microscopy is a rapidly expanding optical technique with excellent surface sensitivity and limited background fluorescence. Commercially available TIRF systems are either objective based that employ expensive special high numerical aperture (NA) objectives or prism based that restrict integrating other modalities of investigation for structure-function analysis. Both techniques result in uneven illumination of the field of view and require training and experience in optics. Here we describe a novel, inexpensive, LED powered, waveguide based TIRF system that could be used as an add-on module to any standard fluorescence microscope even with low NA objectives. This system requires no alignment, illuminates the entire field evenly, and allows switching between epifluorescence/TIRF/bright field modes without adjustments or objective replacements. The simple design allows integration with other imaging systems, including atomic force microscopy (AFM), for probing complex biological systems at their native nanoscale regimes.

Published
2013

49. Plasma imatinib levels and ABCB1 polymorphism influences early molecular response and failure-free survival in newly diagnosed chronic phase CML patients

Author

Rajamani, Bharathi M., Benjamin, Esther Sathya Bama, Abraham, Aby, Ganesan, Sukanya, Lakshmi, Kavitha M., Anandan, Senthamizhselvi, Karathedath, Sreeja, Varatharajan, Savitha, Mohanan, Ezhilpavai, Janet, Nancy Beryl, Srivastava, Vivi M., Ramachandran Velayudhan, Shaji, Kulkarni, Uday P., Devasia, Anup J., Fouzia, N. A., Korula, Anu, George, Biju, Srivastava, Alok, Mathews, Vikram, and Balasubramanian, Poonkuzhali

Published
2020
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results