Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 117
Filtrar
1.
Materials (Basel) ; 17(7)2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38612103

RESUMEN

The rotor or impeller is a rotational and key part of a pump and compressor. This article presents the detailed development process of a rotor of small size constructed from an EN8 steel cylindrical blank using a novel technique based on a computer numerical control engraving milling machine (CNC-EMM) equipped with a 4 mm tungsten carbide end mill cutter. We fabricated a total of twenty-eight stepped rotors following the Box-Behnken Design (BBD) DoE technique at fourteen distinct combinations of CNC-EMM variable parameters, namely rotational speed, feed, and plunge feed. Average roughness 'Ra', an important surface quality indicator, has been considered and presented in this article, as a quality measure for the fabricated rotors. Feed and plunge feed have been identified as the most influencing variable parameters as per an analysis of variance (ANOVA) test. The lowest average roughness value obtained by this process for the rotor blade was 0.11 µm. A micrograph obtained from a field-emission scanning electron microscope (FE-SEM) showed a uniform and accurate tooth profile along with burr formation at corner edges. This study claims to establish engraving milling as a viable alternative to other manufacturing processes used for rotor blades. The findings of this study are useful to scholars, engineers, and researchers who are exploring new ways to fabricate mechanical parts and components.

2.
Biochim Biophys Acta Gene Regul Mech ; 1867(2): 195026, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38641240

RESUMEN

Preserving the genomic integrity stands a fundamental necessity, primarily achieved by the DNA repair proteins through their continuous patrolling on the DNA in search of lesions. However, comprehending how even a single base-pair lesion can be swiftly and specifically recognized amidst millions of base-pair sites remains a formidable challenge. In this study, we employ extensive molecular dynamics simulations using an appropriately tuned model of both protein and DNA to probe the underlying molecular principles. Our findings reveal that the dynamics of a non-canonical base generate an entropic signal that guides the one-dimensional search of a repair protein, thereby facilitating the recognition of the lesion site. The width of the funnel perfectly aligns with the one-dimensional diffusion length of DNA-binding proteins. The generic mechanism provides a physical basis for rapid recognition and specificity of DNA damage sensing and recognition.


Asunto(s)
Daño del ADN , Reparación del ADN , ADN , Simulación de Dinámica Molecular , ADN/metabolismo , Proteínas de Unión al ADN/metabolismo , Nucleótidos/metabolismo , Unión Proteica , Humanos
3.
J Otol ; 19(1): 46-54, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38313757

RESUMEN

Purpose: This review article provides the readers with an in-depth insight in understanding and interpreting various research literatures on the masseter vestibular evoked myogenic potentials (mVEMP). The article also reviews the contemporary researches involving the clinical applications of the mVEMP. Conclusions: Masseter VEMP is an evolving yet clinically promising neuro-otology test tool that has recently gained more research interest and is considered an additional tool to diagnose various vestibular disorders. Masseter VEMP assesses the functional integrity of the acoustic-masseteric and vestibulo-masseteric reflex pathways. The mVEMP could be used as a complementary test to evaluate the same peripheral generator as the cervical VEMP but a different central pathway i.e., vestibulo-trigeminal pathway. Various research studies that have experimented on parameters such as the effect of different electrode montages (zygomatic vs mandibular configurations), stimulation rates, filter settings and stimuli used to evoke mVEMP have been discussed in this article that could assist in the optimization of a comprehensive clinical protocol. The latency and the amplitude of mVEMP waveforms serve as significant parameters in differentiating normals from those of the clinical populations. Along with the cVEMPs and oVEMPs, mVEMP might help diagnose brainstem lesions in REM Sleep behaviour disorders, Multiple Sclerosis and Parkinson's disease. However, further studies are required to probe in this area of research.

4.
Lancet Reg Health Southeast Asia ; 18: 100304, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38028158

RESUMEN

Health Emergency Risk Management (ERM) has become increasingly critical on the global stage, prompted by the escalating frequency and severity of natural disasters and disease outbreaks. This paper offers a comprehensive synthesis of the World Health Organization's (WHO) experiences in the South-East Asia Region during the period 2014-2023, shedding light on its efforts to manage health emergencies and enhance resilience. The South-East Asia Region's unique environmental and economic diversity exposes it to significant health risks, including emerging infectious diseases and their implications for development, particularly in low-income countries. Here we document the transition from reactive emergency responses to proactive preparedness, catalyzed by prioritizing ERM as one of the regional flagship priorities in 2014. Key components of this initiative included capacity-building, the establishment of the South-East Asia Regional Health Emergency Fund (SEARHEF), and the implementation of the International Health Regulations (IHR 2005). This synthesis highlights the region's achievements in event reporting, development of national actions plan, successful Early Warning, Alert, and Response System (EWARS) implementation, and improvements in core capacities under IHR (2005). It also underscores the challenges associated with cross-border data sharing and regional collaboration that could strengthen ERM and enhance readiness for effective synergistic response.

5.
Sci Rep ; 13(1): 18152, 2023 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-37875501

RESUMEN

The trans-Himalayan region of India, although have xeric features, still supports a unique assemblage of biodiversity, including some of the charismatic and endemic species. In the present study, we studied blue sheep (Pseudois nayaur) across the distribution range in the Western trans Himalayas of India and found about 18,775 km2 area suitable for blue sheep. The explicit Bayesian based spatial and non-spatial population structure analysis assigned blue sheep into two genetic populations, i.e., Ladakh and Lahaul-Spiti. We found relatively high genetic divergence in blue sheep which is also supported by the low current flow in Circuitscape model. With the multiple evidences, we explain landscape resistance facilitated by the landscape heterogeneity, and large patches of unsuitable habitats forced population divergence and poor functional connectivity. We found that blue sheep population has been demographically stable in the past, but showed a slight decline within the last few decades. This study is the first range-wide attempt to exhibit landscape features in shaping the spatial distribution, genetic structure and demography patterns of blue sheep in Western Himalayas, and will be of use in the conservation and management planning of blue sheep.


Asunto(s)
Ecosistema , Genética de Población , Animales , Ovinos/genética , Teorema de Bayes , Biodiversidad , Flujo Genético
6.
Plant Physiol Biochem ; 203: 108039, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37717347

RESUMEN

Arbuscular mycorrhiza (AM) has been reported to influence secondary metabolism of Ocimum tenuiflorum L., thereby improving its therapeutic and commercial importance. To explain changes in the secondary metabolite profile, the study reports effects of AM on leaf metabolome of two high yielding genotypes of O. tenuiflorum inoculated with Rhizophagus intraradices. NMR-based non-targeted metabolic fingerprinting was related to changes at physiological, biochemical, and molecular levels in mycorrhizal (M) plants. AM resulted in higher accumulation of sucrose, which could be related with enhanced photosynthesis by virtue of increased uptake of mineral nutrients. A strong positive correlation between sucrose and net photosynthetic rate and sucrose and mineral nutrients supported that AM-mediated increase in uptake of mineral nutrients is associated with enhanced photosynthetic rate and accumulation of sucrose. Further, higher sucrose synthase activity resulted in increased glucose. Hexokinase activity was also higher in M plants resulting in higher pyruvate accumulation. On the contrary, Krebs cycle was compromised in M plants as evident by lower activities of its enzymes and concentrations of organic and amino acids. Nevertheless, AM increased activities and expressions of enzymes of terpenoid biosynthesis, shikimate, and phenylpropanoid pathways, thereby resulting in augmented production of terpenoids, phenylalanine, and phenols, respectively. Thus, metabolic reprogramming downstream of glycolysis was apparent wherein AMF resulted in more allocation of carbon resources to secondary metabolism as opposed to primary metabolism, which was supported by Pearson's correlation analysis. Higher C:N ratio in M plants explains the provision of more carbon resources to secondary metabolism as against primary metabolism.

7.
J Phys Chem B ; 127(25): 5702-5717, 2023 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-37310883

RESUMEN

Nearly three-fourths of all eukaryotic DNA is occupied by nucleosomes, protein-DNA complexes comprising octameric histone core proteins and ∼150 base pairs of DNA. In addition to acting as a DNA compaction vehicle, the dynamics of nucleosomes regulate the DNA site accessibility for the nonhistone proteins, thereby controlling regulatory processes involved in determining the cell identity and cell fate. Here, we propose an analytical framework to analyze the role of nucleosome dynamics on the target search process of transcription factors through a simple discrete-state stochastic description of the search process. By considering the experimentally determined kinetic rates associated with protein and nucleosome dynamics as the only inputs, we estimate the target search time of a protein via first-passage probability calculations separately during nucleosome breathing and sliding dynamics. Although both the nucleosome dynamics permit transient access to the DNA sites that are otherwise occluded by the histone proteins, our result suggests substantial differences between the protein search mechanism on a nucleosome performing breathing and sliding dynamics. Furthermore, we identify the molecular factors that influence the search efficiency and demonstrate how these factors together portray a highly dynamic landscape of gene regulation. Our analytical results are validated using extensive Monte Carlo simulations.


Asunto(s)
Histonas , Nucleosomas , Histonas/metabolismo , ADN/metabolismo , Factores de Transcripción/genética
8.
Materials (Basel) ; 16(11)2023 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-37297143

RESUMEN

This paper reports the surface quality of a miniature cylindrical titanium rod/bar (MCTB) turned by the wire electrical discharge turning (WEDT) process using a zinc-coated wire of 250 µm diameter. The surface quality was mainly evaluated by considering the very important surface roughness parameters, i.e., the mean roughness depth. A Box-Behnken design (BBD) of the response surface methodology (RSM) based on 17 experimental runs was conducted, where the spark duration "Ton" was found as the most influential parameter affecting the mean roughness depth "RZ" of the miniature titanium bar. Further, using the grey relational analysis (GRA) technique of optimization, we obtained the least value of "RZ" 7.42 µm after machining a miniature cylindrical titanium bar with the optimum combination of WEDT's variable parameters: Ton-0.9 µs, SV-30 V, and DOC-0.35 mm. This optimization led to a 37% reduction in the surface roughness Rz of the MCTB. The tribological characteristics of this MCTB were also found favorable after conducting a wear test. After completing a comparative study, we can claim that our results are better than those of the past research conducted in this area. The findings of this study are beneficial for the micro-turning of cylindrical bars made from a variety of difficult-to-machine materials.

9.
Micromachines (Basel) ; 14(6)2023 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-37374732

RESUMEN

This paper presents a research investigation conducted on the turning of stainless steel 316 material under a dry environment using microwave-treated cutting tool inserts. Plain tungsten carbide WC tool inserts were exposed to microwave treatment for enhancement of their performance characteristics. It was found that a 20-min microwave treatment resulted in the best tool hardness and metallurgical characteristics. These tool inserts have been used to machine SS 316 material following the Taguchi L9 design of experimental techniques. A total of eighteen experiments have been conducted by varying three main machining parameters, i.e., cutting speed, feed rate, and depth of cut, at three levels per parameter. It has been found that tool flank wear increased with all three parameters and surface roughness decreased. At the longest dept of cut, surface roughness increased. An abrasion wear mechanism was found on the tool flank face at a high machining speed and adhesion at low speed. Chips with a helical shape and low serrations have been investigated. Turning SS 316 at optimum machining parameters of 170 m/min cutting speed, 0.2 mm/rev feed rate, and 1 mm depth of cut, as obtained by the multiperformance optimization technique grey relational analysis, resulted in the best values of all machinability indicators: 242.21 µm tool flank wear, 3.81 µm mean roughness depth, and 34,000 mm3/min material removal rate, at a single parameter setting. In terms of research achievements, the percentage reduction in surface roughness is approximately 30% and represents an almost ten-fold improvement in the material removal rate. The combination of machining parameters of 70 m/min cutting speed, 0.1 mm/rev feed rate, and 0.5 mm depth of cut is optimum for the lowest value of tool flank wear when considered for single parameter optimization.

10.
Biomed Pharmacother ; 164: 114938, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37267635

RESUMEN

In the current period of drug development, natural products have provided an unrivaled supply of anticancer medications. By modifying the cancer microenvironment and various signaling pathways, natural products and their derivatives and analogs play a significant role in cancer treatment. These substances are effective against several signaling pathways, particularly the cell death pathways (apoptosis and autophagy) and embryonic developmental pathways (Notch, Wnt, and Hedgehog pathways). Natural products have a long history, but more research is needed to understand their current function in the research and development of cancer treatments and the potential for natural products to serve as a significant source of therapeutic agents in the future. Several target-specific anticancer medications failed to treat cancer, necessitating research into natural compounds with multiple target properties. To help develop a better treatment plan for managing breast cancer, this review has outlined the anticancerous potential of several therapeutic approaches targeting the notch signaling system in breast tumors.


Asunto(s)
Antineoplásicos , Productos Biológicos , Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/patología , Proteínas Hedgehog/metabolismo , Transducción de Señal , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Productos Biológicos/farmacología , Receptores Notch/metabolismo , Microambiente Tumoral
11.
J Diabetes ; 2023 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-37292055

RESUMEN

Both diabetes mellitus (DM) and tuberculosis (TB) are prevalent all across in India. TB-DM comorbidity has emerged as a syndemic and needs more attention in India considering gaps in screening, clinical care, and research. This paper is intended to review published literature on TB and DM in India to understand the burden of the dual epidemic and its trajectory and to obtain perspectives on the gaps, constraints, and challenges in care and treatment of this dual epidemic. A literature search was carried out on PubMed, Scopus, and Google Scholar, using the key words 'Tuberculosis' OR 'TB' AND 'Diabetes' OR 'Diabetes Mellitus' AND 'India', focusing on the research published between the year 2000 to 2022. The prevalence of DM is high in patients with TB. Quantitative data on the epidemiological situation of TB/DM in India such as incidence, prevalence, mortality, and management are lacking. During the last 2 years convergence of TB-DM syndemic with the COVID-19 pandemic has increased cases with uncontrolled DM but also made coordinated control of TB-DM operationally difficult and of low effectiveness. Research regarding TB-DM comorbidity is required in the context of epidemiology and management. Detection and bidirectional screening are aggressively warranted. Management of DM in those with TB-DM comorbidity needs more efforts, including training and supervision of frontline workers.

12.
Cureus ; 15(3): e35848, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37033527

RESUMEN

INTRODUCTION: Lung cancer is the leading cause amongst the cancer deaths in the world. Detection of malignancy at an early stage and with precision is the utmost objective of radiological evaluation. The final diagnosis of lung cancer is histopathological evaluation of the mass. The authors hereby have tried to convert the multi-detector CT (MDCT) characteristics and patient demographics into quantitative data to formulate a scoring system that can predict lung malignancy as close to histopathology as possible. MATERIALS AND METHODS: After obtaining ethical clearance, 104 cases of suspected lung cancer by history, clinical and radiographic evaluation were enrolled in the study. These patients were undergoing CT thorax (contrast) on 384 slice siemens somatom force. After undergoing the radiological evaluation biopsy of the mass was done either by CT guided or bronchoscopy guided. Radiological and histopathological findings were correlated. Patients aged >50, lymphadenopathy, tumor volume >50 cc, enhancement >15 HU (Hounsfield unit) after contrast injection were given a score of 15 each. History of smoking, bronchus cut off, spiculated/lobulated margins, mediastinal/pleural involvement, and angiogram sign positive were given a score of 20 each. So, a maximum score of 160 can be achieved by history and MDCT evaluation. RESULTS: Sensitivity, specificity, positive predictive values (PPV), negative predictive values (NPV), and diagnostic accuracy of MDCT by using conventional parameters against histopathology was 97.5%, 85%, 96.29%, 89.47%, and 95.0%. The sensitivity and specificity calculated through Receiver-Operating-Characteristic (ROC) for predicting malignancy were found to be 98.8% and 90.0% for a cut-off score of >97.5 out of maximum of 160.  Conclusion: MDCT serves as a tool for early diagnosis of lung cancer, and it is the utmost important tool for cases where biopsy or fine needle aspiration cytology (FNAC) is not possible. By creating a quantitative criterion to diagnose lung malignancy, the subjective nature of MDCT diagnosis can be converted into an objective based evaluation.

13.
Biology (Basel) ; 12(3)2023 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-36979074

RESUMEN

Wildlife corridors that connect mosaic habitats in heterogeneous mountainous landscapes can be of high significance as they facilitate the genetic and demographic stability of free-ranging populations. Peripheral populations of widespread species are usually ignored in conservation planning. However, these populations retain locally common alleles and are genetic reservoir under the changing climatic conditions. Capra sibirica has widespread distribution, and its southern peripheral population is distributed in the Indian trans-Himalayan region (ITR). In the present study, we studied the spatial distribution and genetic make-up of Himalayan ibex from the ITR following the landscape genetics approach. We obtained 16 haplotypes at the mitochondrial d-loop region and found a stable demography in the past with a recent decline. With 10 nuclear microsatellites, we ascertained 111 unique individuals assigned into two clusters following Bayesian and non-Bayesian clustering analysis with several admixed individuals. We also recorded 25 first-generation migrants that reflected relatively high dispersal and gene-flow across the range. We identified a 19,835 sq.km suitable area with 13,311 sq.km in Ladakh and 6524 sq.km in Lahaul-Spiti. We identified a novel movement corridor for Himalayan ibex across the Lahaul-Zanskar-Sham valley (L-Z-SV) that displayed a fairly good conductance with low genetic divergence among the samples collected on the L-Z-SV corridor. We propose declaring a protected area in the Lahaul and Kargil districts to prioritize dedicated conservation efforts for the Himalayan ibex and other sympatric ungulates that impart a major role in the diet of large carnivore and balancing ecosystem services in the trans-Himalayan region.

14.
Trans R Soc Trop Med Hyg ; 117(1): 45-49, 2023 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-36107937

RESUMEN

BACKGROUND: Muzaffarpur district in Bihar State of India recorded a resurgence of acute encephalopathy syndrome (AES) cases in the summer of 2019 after no reported outbreak in 3 y. Earlier studies generated evidence that litchi consumption and missing the previous evening's meal were associated with AES. We investigated the recent outbreak to understand the risk factors associated with AES. METHODS: We conducted a matched case-control study by comparing AES cases with healthy controls from case-households and the neighborhood community for risk factors like missing evening meal and litchi consumption before onset of AES. RESULTS: We recruited 61 cases and 239 controls. Compared with the community controls, case-patients were five times more likely to have reported eating litchi in the 7 d preceding the onset of illness (adjusted OR [AOR]=5.1; 95% CI 1.3 to 19) and skipping the previous evening's meal (AOR=5.2; 95% CI 1.4 to 20). Compared with household controls, case-patients were five times more likely to be children aged <5 y (AOR=5.3; 95% CI 1.3 to 22) and seven times more likely to have skipped the previous evening's meal (AOR=7.4; 95% CI 1.7 to 34). CONCLUSIONS: Skipping the previous evening's meal and litchi consumption were significantly associated with AES among children in Muzaffarpur and adjoining districts of Bihar.


Asunto(s)
Encefalopatías , Litchi , Humanos , Niño , Estudios de Casos y Controles , Encefalopatías/epidemiología , Encefalopatías/etiología , India/epidemiología , Brotes de Enfermedades , Comidas
15.
Ann Oper Res ; : 1-48, 2022 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-36467003

RESUMEN

Blockchain technology is touted as a game-changer. Many experts consider blockchain technology as one of the disruptive innovations. Following significant success in the banking and finance sector, blockchain technology has found significant success in all fields, including health, manufacturing, transportation, disaster relief operations, and many others. Recently, the academician has contributed significantly towards understanding blockchain technology and its application in the management field. To understand how the literature on blockchain technology in the supply chain has progressed, we undertook an extensive review of the literature published in peer-reviewed journals using databases such as SCOPUS. We have further classified our literature into four stages (pre-adoption, adoption, implementation, and application). Finally, we synthesized the findings of the study and proposed a research framework to explain how an organization can build supply chain resilience and enhance supply chain performance with the help of blockchain technology. Finally, we have noted the limitations of the study and future research directions.

16.
Emerg Infect Dis ; 28(13): S138-S144, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36502396

RESUMEN

The India Field Epidemiology Training Program (FETP) has played a critical role in India's response to the ongoing COVID-19 pandemic. During March 2020-June 2021, a total of 123 FETP officers from across 3 training hubs were deployed in support of India's efforts to combat COVID-19. FETP officers have successfully mitigated the effect of COVID-19 on persons in India by conducting cluster outbreak investigations, performing surveillance system evaluations, and developing infection prevention and control tools and guidelines. This report discusses the successes of select COVID-19 pandemic response activities undertaken by current India FETP officers and proposes a pathway to augmenting India's pandemic preparedness and response efforts through expansion of this network and a strengthened frontline public health workforce.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , COVID-19/prevención & control , Pandemias/prevención & control , Brotes de Enfermedades/prevención & control , India/epidemiología
17.
Front Neurol ; 13: 948462, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36570452

RESUMEN

Introduction: Acute unilateral vestibular hypofunction is characterized by sudden onset of vertigo or dizziness, vomiting/nausea, gait instability, and nystagmus. This is commonly described as an acute vestibular syndrome and usually attributed to vestibular neuritis; however, up to 25% of acute vestibular syndrome is caused by a stroke of posterior circulations. The video head impulse test is a recent tool in the vestibular test battery that assesses the vestibule-ocular reflex by measuring the VOR gain and recording overt and covert saccades, these findings have been found to be helpful in the diagnosis of various vestibular disorders. Method: A literature search was conducted in databases, including PubMed Central, PubMed, and Web of Science. All the articles that define video head impulse test (vHIT), acute vestibular hypofunction, and vestibular neuritis were considered for the preliminary search. No limits were placed on the date of publication. The searches were limited to studies with full-text availability, published in English, and including human subjects. Search words such as "head impulse test," "video head impulse test," "vestibular ocular reflex," "acute vestibular syndrome," "acute vestibular hypofunction," "vestibular neuritis," and "vHIT in central vestibular disorders" were entered into different databases in different combinations using boolean operators such as AND, OR, and NOT. Results: Searches across different databases, including Web of Science, PubMed Central, and PubMed, resulted in a total of 1,790 articles. Title screening was done for all the articles. Out of the 1,790 articles, we found that 245 articles were related to vestibular hypofunction i.e., 1,545 articles were removed at this stage. A further 56 duplicate articles were removed. This led to a final screening of 189 articles. The exclusion criteria included unavailability of full text, studies reported in languages other than English, case reports, reviews, and articles including participants having other comorbid conditions. This final screening led to 133 articles being excluded, which led to the full-text screening of 56 articles. After screening the full-text articles as per the eligibility criteria, 21 articles were found to be eligible for the systematic review. Among the remaining studies, six articles were excluded due to different specific reasons. A total of 15 articles were included in this systematic review. The mean VOR gain for the patients with vestibular neuritis was 0.48 ± 0.14 for the ipsilesional ear, whereas the mean VOR gain was > 0.80 in the contralesional ear for all the patients with acute vestibular neuritis. In patients with PICA lesions, the VOR gain for the ipsilesional ear was 0.90 (range 0.87-0.94) and for the contralesional ear was 0.88 (range 0.84-0.93). In patients with AICA lesions, the mean VOR gain was variable. Based on the above mean VOR gain findings, the authors propose the following adjective description scale of VOR of the lateral canal using vHIT: normal VOR gain above 0.80, mild VOR gain loss for 0.70-0.79, moderate loss for 0.69-0.4, severe loss for 0.39-0.2, and profound loss for < 0.2.

18.
Biophys J ; 121(23): 4526-4542, 2022 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-36321206

RESUMEN

Critical lineage commitment events are staged by multiple transcription factors (TFs) binding to their cognate motifs, often positioned at nucleosome-enriched regions of chromatin. The underlying mechanism remains elusive due to difficulty in disentangling the heterogeneity in chromatin states. Using a novel coarse-grained model and molecular dynamics simulations, here we probe the association of Sox2 and Oct4 proteins that show clustered binding at the entry-exit region of a nucleosome. The model captures the conformational heterogeneity of nucleosome breathing dynamics that features repeated wrap-unwrap transitions of a DNA segment from one end of the nucleosome. During the dynamics, DNA forms bulges that diffuse stochastically and may regulate the target search dynamics of a protein by nonspecifically interacting with it. The overall search kinetics of the TF pair follows a "dissociation-compensated-association" mechanism, where Oct4 binding is facilitated by the association of Sox2. The cooperativity stems from a change in entropy caused by an alteration in the nucleosome dynamics upon TF binding. The binding pattern is consistent with a live-cell single-particle tracking experiment, suggesting the mechanism observed for clustered binding of a TF pair, which is a hallmark of cis-regulatory elements, has broader implications in understanding gene regulation in a complex chromatin environment.


Asunto(s)
ADN , Nucleosomas
19.
Sci Total Environ ; 853: 158679, 2022 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-36099955

RESUMEN

Large forested landscapes often harbour significant amount of biodiversity and support mankind by rendering various livelihood opportunities and ecosystem services. Their periodic assessment for health and ecological integrity is essential for timely mitigation of any negative impact of human use due to over harvesting of natural resources or unsustainable developmental activities. In this context, monitoring of mega fauna may provide reasonable insights about the connectivity and quality of forested habitats. In the present study, we conducted a largest non-invasive genetic survey to explore mammalian diversity and genetically characterized 13 mammals from the Indian Himalayan Region (IHR). We analyzed 4806 faecal samples using 103 autosomal microsatellites and with three mitochondrial genes, we identified 37 species of mammal. We observed low to moderate level of genetic variability and most species exhibited stable demographic history. We estimated an unbiased population genetic account (PGAunbias) for 13 species that may be monitored after a fixed time interval to understand species performance in response to the landscape changes. The present study has been evident to show pragmatic permeability with the representative sampling in the IHR in order to facilitate the development of species-oriented conservation and management programmes.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Animales , Humanos , Biodiversidad , Mamíferos/genética
20.
Indian J Med Res ; 155(5&6): 478-484, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35946230

RESUMEN

Background & objectives: Data from the National Clinical Registry for COVID-19 (NCRC) were analyzed with an aim to describe the clinical characteristics, course and outcomes of patients hospitalized with COVID-19 in the third wave of the pandemic and compare them with patients admitted earlier. Methods: The NCRC, launched in September 2020, is a multicentre observational initiative, which provided the platform for the current investigation. Demographic, clinical, treatment and outcome data of hospitalized COVID-19 patients were captured in an electronic data portal from 38 hospitals across India. Patients enrolled during December 16, 2021 to January 17, 2022 were considered representative of the third wave of COVID-19 and compared with those registered during November 15 to December 15, 2021, representative of the tail end of the second wave. Results: Between November 15, 2021 and January 17, 2022, 3230 patients were recruited in NCRC. Patients admitted in the third wave were significantly younger than those admitted earlier (46.7±20.5 vs. 54.6±18 yr). The patients admitted in the third wave had a lower requirement of drugs including steroids, interleukin (IL)-6 inhibitors and remdesivir as well as lower oxygen supplementation and mechanical ventilation. They had improved hospital outcomes with significantly lower in-hospital mortality (11.2 vs. 15.1%). The outcomes were better among the fully vaccinated when compared to the unvaccinated or partially vaccinated. Interpretation & conclusions: The pattern of illness and outcomes were observed to be different in the third wave compared to the last wave. Hospitalized patients were younger with fewer comorbidities, decreased symptoms and improved outcomes, with fully vaccinated patients faring better than the unvaccinated and partially vaccinated ones.


Asunto(s)
COVID-19 , Gripe Humana , Humanos , COVID-19/epidemiología , Gripe Humana/epidemiología , Pandemias , Hospitalización , Sistema de Registros
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...