Publications by authors named "Archana Nagarajan"

Motivated by studies showing an association between beta blocker (BB) use and positive bone outcomes, a pilot randomized control trial (RCT) was performed at the Mayo Clinic which randomized postmenopausal women to placebo, propranolol (40 or 80 mg twice daily), atenolol (50 mg/day), or nebivolol (5 mg/day) to determine changes in bone turnover markers (BTMs) and in bone mineral density (BMD) over 20 weeks. Pharmacogenetic effects and microRNA-mediated mechanisms involving beta adrenergic receptor and related genes have previously been found. We sought to validate these effects and discover new candidates in an ancillary study to the pilot clinical trial.

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Article Synopsis
  • Alzheimer's disease and osteoporosis are common age-related conditions linked by unknown molecular mechanisms, prompting this study.
  • Researchers conducted network analysis of brain and bone RNA data from several participants to identify shared molecular pathways.
  • Findings revealed interconnected gene modules between both diseases, particularly highlighting the role of Wnt signaling, suggesting potential avenues for treatment and biomarker development.
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Article Synopsis
  • The study investigates whether baseline bone mineral density (BMD) or the rate of bone loss before the baseline is a better predictor of developing dementia and Alzheimer's disease (AD).
  • A meta-analysis involved data from three longitudinal studies with over 4,400 participants aged 60 and above, focusing on BMD measurements and their correlation with dementia diagnoses within a 10-year follow-up.
  • Results indicated that higher baseline BMD is significantly linked to a lower risk of dementia, while prior bone loss only showed a significant relationship in one of the studies included.
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In Poland, Lyme borreliosis (LB) has been subject to mandatory public health surveillance since 1996 and, in accordance with EU regulations, Lyme neuroborreliosis has been reported to the European Centre for Disease Prevention and Control since 2019. In this study, the incidence, temporal trends, and geographic distribution of LB and its manifestations in Poland are described for the period 2015-2019. This retrospective incidence study of LB and its manifestations in Poland was based on data sent to the National Institute of Public Health-National Institute of Hygiene-National Research Institute (NIPH-NIH-NRI) by district sanitary epidemiological stations using the electronic Epidemiological Records Registration System and data from the National Database on Hospitalization.

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Lyme borreliosis (LB) is the most prevalent tick-borne disease in Europe and the incidence of LB is increasing owing to an expansion in tick habitats. However, LB surveillance is quite heterogeneous across the continent, and for those countries with publicly available data, it is difficult to understand the differences in incidence between countries. The objective of our study was to summarize the publicly available data from surveillance for LB in the form of surveillance reports and/or dashboards and to compare the information available for various countries.

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Introduction: There is a scarcity of information on the incidence and outcomes of acute kidney injury (AKI) in COVID-19 patients in India. Therefore, we analyzed the correlation of AKI risk factors, ventilatory support, and renal replacement therapy and compared the outcomes of first and second COVID-19 waves in this tertiary care center.

Methods: We retrospectively analyzed the patients' medical records with a positive RT-PCR for COVID-19 between July 2020 and May 2021.

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Context: Recent studies have shown that β-blocker (BB) users have a decreased risk of fracture and higher bone mineral density (BMD) compared to nonusers, likely due to the suppression of adrenergic signaling in osteoblasts, leading to increased BMD. There is also variability in the effect size of BB use on BMD in humans, which may be due to pharmacogenomic effects.

Objective: To investigate potential single-nucleotide variations (SNVs) associated with the effect of BB use on femoral neck BMD, we performed a cross-sectional analysis using clinical data, dual-energy x-ray absorptiometry, and genetic data from the Framingham Heart Study's (FHS) Offspring Cohort.

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Pannexins are a 3-membered family of proteins that form large pore ion and metabolite channels in vertebrates. The impact of pannexins on vertebrate biology is intricately tied to where and when they are expressed, and how they are modified, once produced. The purpose of this review is therefore to outline our current understanding of transcriptional and post-translational regulation of pannexins.

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Multiple experimental evolution studies on Drosophila melanogaster in the 1980s and 1990s indicated that enhanced competitive ability evolved primarily through increased larval tolerance to nitrogenous wastes and increased larval feeding and foraging rate, at the cost of efficiency of food conversion to biomass, and this became the widely accepted view of how adaptation to larval crowding evolves in fruitflies.We recently showed that populations of D. ananassae and D.

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The standard view of adaptation to larval crowding in fruitflies, built on results from 25 years of multiple experimental evolution studies on Drosophila melanogaster, was that enhanced competitive ability evolves primarily through increased larval feeding and foraging rate, and increased larval tolerance to nitrogenous wastes, at the cost of efficiency of food conversion to biomass. These results were at odds from the predictions of classical K-selection theory, notably the expectation that selection at high density should result in the increase of efficiency of conversion of food to biomass, and were better interpreted through the lens of α-selection. We show here that populations of D.

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Potential health effects of radiofrequency (RF) radiation from mobile phones arouse widespread public concern. RF fields from handheld devices near the brain might trigger or aggravate brain tumors or neurodegenerative diseases such as Parkinson's disease (PD). Aggregation of neural α-synuclein (S) is central to PD pathophysiology, and invertebrate models expressing human S have helped elucidate factors affecting the aggregation process.

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The aggregation of α-synuclein (Syn or S) to form insoluble fibrils is important in the pathogenesis of Parkinson's disease, but key risk factors remain ill-defined. We have developed Fluorescence Resonance Energy Transfer (FRET)-based assays for α-synuclein aggregation, using Green Fluorescent Protein variants Cerulean (C) or Venus (V), fused to each other (CV, VC) or to human synuclein (SC, SV etc). Bacterially expressed proteins were purified to homogeneity, and C-terminal fusions SC and SV largely retained their ability to aggregate in vitro.

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Progressive neurodegenerative diseases are among the most frequently occurring aging-associated human pathologies. In a screen for Caenorhabditis elegans mutant animals that lack their normal complement of dopaminergic neurons, we identified two strains with progressive loss of dopaminergic neurons during postembryonic life. Through whole-genome sequencing we show that both strains harbor dominant (d), gain-of-function mutations in the Transient Receptor Potential (TRP) mechanosensory channel trp-4, a member of the invertebrate and vertebrate TRPN-type of the TRP family channels.

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The neural protein α-synuclein aggregates both in vivo and in vitro to form insoluble fibrils that are involved in Parkinson's disease pathogenesis. We have generated α-synuclein/fluorescent-protein fusion constructs overexpressed in muscle cells of the nematode, Caenorhabdtis elegans. Green Fluorescent Protein (GFP) variants, Cerulean (C) or Venus (V), were fused to the C-terminus of human α-synuclein (S); the resultant fusion genes were designated SV and SC, plus a CV fusion as well as S, C and V singly.

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