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Hydroquinone is a phenolic compound commonly found in the raw materials and finished products of various chemical industries. Its widespread usage carries significant risks to aquatic and human life and the environment as well. A laccase biosensor was developed here to determine hydroquinone concentration in water resources. In the present study, the screenprinted electrode of the biosensor was coated with a solution of polyvinyl alcohol containing carboxyl functionalised multiwalled carbon nanotubes (MWCNTs). Laccase extracted from the fungus Trametes versicolor was immobilised on MWCNTs using glutaraldehyde. This strategy showed excellent stability, sensitivity, and selectivity, yielding a quick response time of only 10 sec. The electrode surface at different stages of the preparation was characterized using scanning electron microscopy (SEM). The optimized linear range for the bioelectrode spans from 50 µM to 1100 µM. The detection limit achieved with the electrode is 5 µM to 1700 µM. The biosensor detected hydroquinone successfully in real samples, including tap water, sewage water, spiked tap water and spiked sewage water. Further, this biosensor while offering a costeffective, portable device, establishes the efficiency of carboxyl-functionalised MWCNTs in polyvinyl alcohol as matrix for the design of a variety of biosensors. [ABSTRACT FROM AUTHOR]

Abstract Background Cytotoxic T-lymphocyte-associated protein 4 deficiency (CTLA4-D) is an inborn error of immunity (IEI) caused by heterozygous mutations, and characterized by immune cell infiltration into the gut and other organs, leading to intestinal disease, immune dysregulation and autoimmunity. While regulatory T-cell dysfunction remains central to CTLA4-D immunopathogenesis, mechanisms driving disease severity and intestinal pathology are unknown but likely involve intestinal dysbiosis. We determined whether the intestinal microbiome and metabolome could distinguish individuals with severe CTLA4-D and identify biomarkers of disease severity. Results The genera Veillonella and Streptococcus emerged as biomarkers that distinguished CTLA4-D from healthy cohorts from both the National Institutes of Health (NIH) Clinical Center, USA (NIH; CTLA-D, n = 32; healthy controls, n = 16), and a geographically distinct cohort from the Center for Chronic Immunodeficiency (CCI) of the Medical Center - University of Freiburg, Germany (CCI; CTLA4-D, n = 25; healthy controls, n = 24). Since IEIs in general may be associated with perturbations of the microbiota, a disease control cohort of individuals with common variable immunodeficiency (CVID, n = 20) was included to evaluate for a CTLA4-D-specific microbial signature. Despite common IEI-associated microbiome changes, the two bacterial genera retained their specificity as biomarkers for CTLA4-D. We further identified intestinal microbiome and metabolomic signatures that distinguished patients with CTLA4-D having severe vs. mild disease. Microbiome changes were associated with distinct stool metabolomic profiles and predicted changes in metabolic pathways. These differences were impacted by the presence of gastrointestinal manifestations and were partially reversed by treatment with abatacept and/or sirolimus. Conclusions Loss of intestinal microbial diversity and dysbiosis causing metabolomic changes was observed in CTLA4-D. Albeit some of these features were shared with CVID, the distinct changes associated with CTLA4-D highlight the fact that IEI-associated microbiome changes likely reflect the underlying immune dysregulation. Identified candidate intestinal microbial and metabolic biomarkers distinguishing individuals with CTLA4-D based on severity should be studied prospectively to determine their predictive value, and investigated as potential therapeutic ta. Video Abstract

UbEP42, a mutant of ubiquitin constitutes four mutations, namely S20F, A46S, L50P, and I61T. Characterization of UbEP42 and the isolated mutations revealed that UbEP42, UbL50P, and UbI61T conferred dosage-dependent lethality on S. cerevisiae, while UbS20F and UbA46S produced no effect over survival. In the present study, opportunistic human pathogen Candida albicans has been employed here to investigate the influence of ubiquitin mutations of S. cerevisiae on morphogenesis, besides various ubiquitin-dependent functions. The codon for leucine 'CUG' in S. cerevisiae is read as serine in C. albicans. Hence the protein variants expressed from the S. cerevisiae gene are added with the prefix 'Sc'. ScUbEP42, ScUbL50P, and ScUbI61T had a negative influence over protein trafficking, lysosomal degradation of proteins, and polyubiquitination with K48 and K63 linkages in C. albicans as in S. cerevisiae. ScUbEP42 and all four derivative mutations impaired the morphogenesis of the yeast form into infective hyphal form. The impairment of morphogenesis of C. albicans by ubiquitin mutations is unprecedented and suggests a target pathway for future therapeutics. [ABSTRACT FROM AUTHOR]

Proteins produce chemical energy by absorbing light in the process of photosynthesis. The use of biological photonic system has recently gained interest, especially in the field of solar energy conservation. The applications of photosynthetic components in photovoltaic material and solar cells are very promising due to their environmental compatibility and efficiency of energy conservation in photosynthesis. The recent advancement in the solar cell design includes the use of photosystem, thylakoid membrane immobilised on polymeric electrode. Previous reports have confirmed the use of PSI as photoelectric material in solar cells. The present work studies the integration of TiO2/PSI complexes with polymer electrodes. Light harvesting complexes (LHC) were isolated from spinach by homogenising cell in lysis buffer. The isolated proteins were then loaded onto DEAE-cellulose a type of ion-exchange chromatography for further purification. TiO2 layer was then spin coated onto Indium Tin Oxide coated (ITO) plates followed by dipping in a solution containing LHCs for 30 min. Upon drying, using spin coating, a thin layer of Polypyrrole electrode was casted onto it. Optical parameters and structural parameters were determined using UV-Vis analysis and XRD respectively. Efficiencies of the resulting devices were calculated under Air mass 1.5 (AM 1.5) conditions. The results establish the successful preparation of a solar cell. [ABSTRACT FROM AUTHOR]

Abstract A decline in mitochondrial function is a hallmark of aging and neurodegenerative diseases. It has been proposed that changes in mitochondrial morphology, including fragmentation of the tubular mitochondrial network, can lead to mitochondrial dysfunction, yet the mechanism of this loss of function is unclear. Most proteins contained within mitochondria are nuclear-encoded and must be properly targeted to the mitochondria. Here, we report that sustained mRNA localization and co-translational protein delivery leads to a heterogeneous protein distribution across fragmented mitochondria. We find that age-induced mitochondrial fragmentation drives a substantial increase in protein expression noise across fragments. Using a translational kinetic and molecular diffusion model, we find that protein expression noise is explained by the nature of stochastic compartmentalization and that co-translational protein delivery is the main contributor to increased heterogeneity. We observed that cells primarily reduce the variability in protein distribution by utilizing mitochondrial fission-fusion processes rather than relying on the mitophagy pathway. Furthermore, we are able to reduce the heterogeneity of the protein distribution by inhibiting co-translational protein targeting. This research lays the framework for a better understanding of the detrimental impact of mitochondrial fragmentation on the physiology of cells in aging and disease.

Introduction: Echocardiography is an indispensable tool for the diagnosis and management of cardiac patients. It is important to know the spectrum of cardiac abnormalities detected by echocardiography for the proper management of patients. The aim of this study was to evaluate the echocardiographic diagnosis of patients at a multispecialty tertiary care hospital and find out the prevalence of various cardiac diseases diagnosed via echocardiography. Methods: This was a retrospective cross sectional study carried out at the Echocardiography lab of National Academy of Health Sciences. Records of all patients who had done Echocardiography from February 2024 to April 2024 were analyzed. Ethical approval was obtained from Institutional Review Committee (Reference Number:1231/2080/81). Results: Out of 3593 cases, there were 1750 (48.71%) female and 1843 (51.29%) male. Normal echocardiographic study was seen in 1184 (32.95%). Mean age was 56.13±17.38 years. Left ventricle diastolic dysfunction was seen among 1428 (39.74%), followed by tricuspid regurgitation 1026 (28.55%) and pulmonary hypertension 497 (13.83%). Other findings were, left ventricular hypertrophy 204 (5.67%), Left ventricular systolic dysfunction 165 (4.59%), rheumatic heart disease 102 (2.83%) and, congenital heart disease was the lowest documented finding, seen in 30 (0.83%). Conclusions: Most common diseases diagnosed by echocardiography in our study were, diastolic dysfunction, tricuspid regurgitation and pulmonary hypertension.