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1.
Antibiotics (Basel) ; 12(10)2023 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-37887197

RESUMEN

(1) Background: Understanding the physicians' knowledge, attitudes, and antimicrobial prescribing behavior is a crucial step towards designing strategies for the optimal use of these agents. (2) Methods: A cross-sectional online survey was conducted among clinicians across India between May and July 2022 using a self-administered questionnaire in English comprising 35 questions pertaining to demographic characteristics, knowledge, attitude, and practices domains. (3) Results: A total of 544 responses were received from 710 physicians contacted. Sixty percent of participants were males, with mean age of 34.7 years. Mean ± Standard Deviation scores for knowledge, attitude, and practices domains were 8 ± 1.6, 20.2 ± 3.5, and 15.3 ± 2.1, respectively. Higher scores were associated with basic [odds ratio (95% Confidence Interval), p value: 2.95 (1.21, 7.2), 0.02], medical and allied sciences [2.71 (1.09, 6.67), 0.03], and central zone [3.75 (1.39, 10.12), 0.009]. A substantial proportion of dissatisfactory responses were found regarding hospital antibiograms, antibiotics effective against anaerobes, WHO AWaRe (access, watch, and reserve) classification of antibiotics, and the role of infection prevention and control (IPC) measures in the containment of antimicrobial resistance (AMR). (4) Conclusions: There is a need to sensitize and educate clinicians on various issues related to antimicrobial use, such as antibiograms, double anaerobic cover, IPC practices, and guideline-based recommendations, to curb the AMR pandemic.

2.
J Family Med Prim Care ; 12(4): 694-700, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37312788

RESUMEN

Background: Healthcare workers (HCWs) are at the front line of the Coronavirus disease (COVID-19) outbreak response. They have faced great risks to both physical and mental health. We aimed to assess the psychological effect of COVID-19 among ancillary hospital staff. Methods: A cross-sectional study was conducted among 267 on-duty ancillary hospital staff using a semi-structured questionnaire to assess their psychological status and risk perception. In addition, their knowledge, attitude, and practices (KAP) and risk perception were also assessed. The General Health Questionnaire (GHQ-12) was used to screen for psychological distress. Results: Among 267 participants, the mean (±SD) age was 33.5 (7.6) years. The majority knew about the symptoms of COVID-19 (88.4%), droplet spread (99.3%), and the importance of isolation (99.3%). About 35.2% were worried about infecting family members, while 26.2% were worried about colleagues at the frontline. Only 38.9% of them had a good knowledge score. Participants with high school and above education level had significantly good knowledge about COVID-19 (OR = 1.99; 95% CI = 1.17- 3.39) than those with primary school or below. Being female (OR 1.99; 95% CI 1.17-3.39) and working with COVID-19 patients (OR 3.88, 95% CI 1.77-8.47, P = 0.001) was associated with psychological distress. Conclusion: The ancillary hospital staff had insufficient knowledge regarding the risk factors of COVID-19 but possessed positive attitudes and practices. Continued health education and appropriate psychological interventions may improve understanding and reduce psychological distress.

3.
Front Mol Neurosci ; 15: 937133, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36090249

RESUMEN

Regulated cell death (RCD) is an ordered and tightly orchestrated set of changes/signaling events in both gene expression and protein activity and is responsible for normal development as well as maintenance of tissue homeostasis. Aberrant activation of this pathway results in cell death by various mechanisms including apoptosis, necroptosis, pyroptosis, ferroptosis, and autophagy-dependent cell death. Such pathological changes in neurons alone or in combination have been observed in the pathogenesis of various neurodegenerative diseases including Alzheimer's disease (AD). Pathological hallmarks of AD focus primarily on the accumulation of two main protein markers: amyloid ß peptides and abnormally phosphorylated tau proteins. These protein aggregates result in the formation of A-ß plaques and neuro-fibrillary tangles (NFTs) and induce neuroinflammation and neurodegeneration over years to decades leading to a multitude of cognitive and behavioral deficits. Autopsy findings of AD reveal massive neuronal death manifested in the form of cortical volume shrinkage, reduction in sizes of gyri to up to 50% and an increase in the sizes of sulci. Multiple forms of cell death have been recorded in neurons from different studies conducted so far. However, understanding the mechanism/s of neuronal cell death in AD patients remains a mystery as the trigger that results in aberrant activation of RCD is unknown and because of the limited availability of dying neurons. This review attempts to elucidate the process of Regulated cell death, how it gets unregulated in response to different intra and extracellular stressors, various forms of unregulated cell death, their interplay and their role in pathogenesis of Alzheimer's Disease in both human and experimental models of AD. Further we plan to explore the correlation of both amyloid-beta and Tau with neuronal loss as seen in AD.

4.
Clin Epidemiol Glob Health ; 17: 101113, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35935532

RESUMEN

Background: Vaccine hesitancy is of considerable concern as it threatens the great potential of a vaccine against COVID-19. This study aims to determine factors associated with community health workers' willingness to participate in clinical trials of COVID-19 vaccine, and their vaccination intention, in India. Methods: A cross-sectional study was conducted among 377 community health workers using self-administered anonymous questionnaire during the lockdown periods in India. Participant's socio-demographics, willingness-to-participate in COVID-19 vaccine trials, intention to accept COVID-19 vaccine were recorded in a Likert scale. Data were analysed descriptively, and a multivariate logistic regression model was used to investigate factors associated with willingness to participate and accept the vaccine. Results: Among 377 CHWs, 70 (19%) intended to participate in COVID-19 vaccine trial, 151 (40%) responded positively regarding their intention to get vaccinated. Those with knowledge on development of COVID-19 vaccine [aOR 3.05 (95% CI: 1.18-7.88), p = 0.021], and men [aOR 3.69 (95% CI: 1.51-8.97), p = 0.004] were more willing to participate in clinical-trial, while an undergraduate degree, and trust in domestic vaccines were identified as deterrents for the same. Perceiving COVID-19 as risk [aOR 2.31 (95% CI: 1.24-4.31), p = 0.009], and male gender [aOR 2.39 (95% CI: 1.17-4.88), p = 0.017] were factors associated with intention to get vaccinated. Respondents who had knowledge about COVID-19 virus were less likely to uptake the hypothetical vaccine [aOR 0.32 (95% CI: 0.12-0.88), p = 0.027]. Conclusions: Increasing knowledge regarding COVID-19 is not enough to improve vaccine acceptance rates. Targeted interventions addressing socio-demographic determinants related to COVID-19 vaccination should help improve acceptance.

5.
Physiol Plant ; 174(1): e13635, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35080785

RESUMEN

AtUSP17 is a multiple stress-inducible gene that encodes a universal stress protein (USP) in Arabidopsis thaliana. In the present study, we functionally characterized AtUSP17 using its knock-down mutant, Atusp17, and AtUSP17-overexpression lines (WTOE). The overexpression of AtUSP17 in wild-type and Atusp17 mutant Arabidopsis plants resulted in higher sensitivity to salt stress during seed germination than WT and Atusp17 mutant lines. In addition, the WTOE and FC lines exhibited higher abscisic acid (ABA) sensitivity than Atusp17 mutant during germination. The exogenous application of ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC) was able to rescue the salt hypersensitive phenotype of WTOE lines. In contrast, AgNO3 , an ethylene action inhibitor, further blocked the effect of ACC during germination. The addition of ACC under salt stress resulted in reduced reactive oxygen species (ROS) accumulation, expression of ABA-responsive genes, improved proline synthesis, increased expression of positive regulators of ethylene signaling and antioxidant defense genes with enhanced antioxidant enzyme activities. The WTOE lines exhibited salt sensitivity even at the adult plant stage, while Atusp17 mutant exhibited higher salt tolerance with higher chlorophyll, relative water content and lower electrolyte leakage as compared with WT. The BAR interaction viewer database and available literature mining identified AtUSP17-interacting proteins, which include RGS1, RACK1C and PRN1 involved in G-protein signaling, which play a crucial role in salt stress responses. Based on the present study and available literature, we proposed a model in which AtUSP17 negatively mediates salt tolerance in Arabidopsis through modulation of ethylene, ABA, ROS, and G-protein signaling and responses.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Ácido Abscísico/metabolismo , Ácido Abscísico/farmacología , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Endopeptidasas , Regulación de la Expresión Génica de las Plantas , Germinación , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/genética , Estrés Salino , Tolerancia a la Sal/genética , Transducción de Señal , Estrés Fisiológico
6.
Cells ; 10(10)2021 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-34685770

RESUMEN

Alzheimer's disease (AD) is one of the most prominent neurodegenerative diseases, which impairs cognitive function in afflicted individuals. AD results in gradual decay of neuronal function as a consequence of diverse degenerating events. Several neuroimmune players (such as cytokines and growth factors that are key players in maintaining CNS homeostasis) turn aberrant during crosstalk between the innate and adaptive immunities. This aberrance underlies neuroinflammation and drives neuronal cells toward apoptotic decline. Neuroinflammation involves microglial activation and has been shown to exacerbate AD. This review attempted to elucidate the role of cytokines, growth factors, and associated mechanisms implicated in the course of AD, especially with neuroinflammation. We also evaluated the propensities and specific mechanism(s) of cytokines and growth factors impacting neuron upon apoptotic decline and further shed light on the availability and accessibility of cytokines across the blood-brain barrier and choroid plexus in AD pathophysiology. The pathogenic and the protective roles of macrophage migration and inhibitory factors, neurotrophic factors, hematopoietic-related growth factors, TAU phosphorylation, advanced glycation end products, complement system, and glial cells in AD and neuropsychiatric pathology were also discussed. Taken together, the emerging roles of these factors in AD pathology emphasize the importance of building novel strategies for an effective therapeutic/neuropsychiatric management of AD in clinics.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Citocinas/metabolismo , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Enfermedad de Alzheimer/inmunología , Quimiocinas/metabolismo , Humanos , Inflamación/patología , Modelos Biológicos
7.
ACS Omega ; 6(34): 22454-22461, 2021 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-34497935

RESUMEN

We present a corroborative study of the structural characterization of lithium-substituted barium vanadate glasses using Raman and electron paramagnetic resonance (EPR) spectroscopy. Investigation of the thermal and physical properties of these glasses showed a gradual increase in the concentration of nonbridging oxygen. Raman and EPR analysis gave an insight into the changing structure of the glasses. Both the spectroscopic techniques confirmed that vanadium is present in the glasses as distorted VO6 octahedra. From the analysis of both spectroscopic techniques, it is proposed that the lithium ion prefers to occupy planar positions of the VO6 octahedra, thus reducing the tetragonal distortion and making the environment around the network-forming unit in the glass matrix more homogeneous as we increase the lithium content. The concentration of V4+ showed a non-monotonic variation with an increase in Li2O as indicated by Raman studies and confirmed by EPR, which indicates a structural change in the distorted VO6 octahedra.

8.
Nutr Res ; 92: 109-128, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34284268

RESUMEN

Novel coronavirus disease 2019 (COVID-19) has spread across the globe; and surprisingly, no potentially protective or therapeutic antiviral molecules are available to treat severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. However, zinc (Zn) and copper (Cu) have been shown to exert protective effects due to their antioxidant, anti-inflammatory, and antiviral properties. Therefore, it is hypothesized that supplementation with Zn and Cu alone or as an adjuvant may be beneficial with promising efficacy and a favorable safety profile to mitigate symptoms, as well as halt progression of the severe form of SARS-CoV-2 infection. The objective of this review is to discuss the proposed underlying molecular mechanisms and their implications for combating SARS-CoV-2 infection in response to Zn and Cu administration. Several clinical trials have also included the use of Zn as an adjuvant therapy with dietary regimens/antiviral drugs against COVID-19 infection. Overall, this review summarizes that nutritional intervention with Zn and Cu may offer an alternative treatment strategy by eliciting their virucidal effects through several fundamental molecular cascades, such as, modulation of immune responses, redox signaling, autophagy, and obstruction of viral entry and genome replication during SARS-CoV-2 infection.


Asunto(s)
Antivirales/farmacología , Tratamiento Farmacológico de COVID-19 , Cobre/farmacología , Oligoelementos/farmacología , Zinc/farmacología , Antiinflamatorios/farmacología , Antioxidantes/farmacología , Humanos , SARS-CoV-2
9.
Indian J Clin Biochem ; 36(4): 387-403, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33875909

RESUMEN

Coronavirus disease 2019 (Covid-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a pandemic disease which has affected more than 6.2 million people globally, with numbers mounting considerably daily. However, till date, no specific treatment modalities are available for Covid-19 and also not much information is known about this disease. Recent studies have revealed that SARS-CoV-2 infection is associated with the generation of thrombosis and coagulopathy. Fundamentally, it has been believed that a diverse array of signalling pathways might be responsible for the activation of coagulation cascade during SARS-CoV-2 infection. Henceforth, a detailed understanding of these probable underlying molecular mechanistic pathways causing thrombosis in Covid-19 disease deserves an urgent exploration. Therefore, in this review, the hypothetical crosstalk between distinct signalling pathways including apoptosis, inflammation, hypoxia and angiogenesis attributable for the commencement of thrombotic events during SARS-CoV-2 infection has been addressed which might further unravel promising therapeutic targets in Covid-19 disease.

10.
Pract Lab Med ; 23: e00195, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33392370

RESUMEN

BACKGROUND: Unreliable and ingenuine results issued by clinical laboratories have serious consequences for the patients. Sigma metrics is a standardized tool for Quality assessment for test performance in a laboratory. OBJECTIVE: To evaluate the performance of routine biochemistry laboratory at MMIMSR, Mullana in terms of Sigma metrics and Quality Goal Index. MATERIAL AND METHODS: This cross sectional study evaluated performance of 14 routine chemistry parameters using retrospective Internal Quality Control data of two levels on Siemens Dimension Rxl from Feb to Jul 2019 for CV% and EQAS reports from CMC, Vellore for Bias%. Sigma metrics was calculated using total allowable error targets as per CLIA and Biological Variability database guidelines. RESULTS: For level-2 IQC; TG, Chol, ALP showed excellent performance with σ â€‹> â€‹6 while σ â€‹< â€‹3 was observed for AST, Total Protein, Glucose, BUN and ALT using CLIA guidelines while in IQC Level-3 poor performers were only BUN and ALT with Ca, TG and Chol showing σ â€‹> â€‹6. Further by using Biological Variability data guidelines; 10 parameters of IQC Level-2 and 5 of IQC level-3 were poor performers with σ â€‹< â€‹3. CONCLUSION: Sigma metrics is an excellent tool for performance analysis of tests performed in a clinical laboratory. Lack of precision in terms of CV% was seen for majority of the poor performers. Total allowable error targets using Biological Variability data revealed σ â€‹< â€‹3 for 10 parameters while using CLIA guidelines σ â€‹< â€‹3 was seen for only 5 parameters of IQC level-2.

11.
J Exp Bot ; 70(21): 6141-6161, 2019 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-31738431

RESUMEN

Iron (Fe) is an essential micronutrient for all organisms. In crop plants, Fe deficiency can decrease crop yield significantly; however, our current understanding of how major crops respond to Fe deficiency remains limited. Herein, the effect of Fe deprivation at both the transcriptomic and metabolic level in hexaploid wheat was investigated. Genome-wide gene expression reprogramming was observed in wheat roots subjected to Fe starvation, with a total of 5854 genes differentially expressed. Homoeologue and subgenome-specific analysis unveiled the induction-biased contribution from the A and B genomes. In general, the predominance of genes coding for nicotianamine synthase, yellow stripe-like transporters, metal transporters, ABC transporters, and zinc-induced facilitator-like protein was noted. Expression of genes related to the Strategy II mode of Fe uptake was also predominant. Our transcriptomic data were in agreement with the GC-MS analysis that showed the enhanced accumulation of various metabolites such as fumarate, malonate, succinate, and xylofuranose, which could be contributing to Fe mobilization. Interestingly, Fe starvation leads to a significant temporal increase of glutathione S-transferase at both the transcriptional level and enzymatic activity level, which indicates the involvement of glutathione in response to Fe stress in wheat roots. Taken together, our result provides new insight into the wheat response to Fe starvation at the molecular level and lays the foundation to design new strategies for the improvement of Fe nutrition in crops.


Asunto(s)
Deficiencias de Hierro , Raíces de Plantas/genética , Poliploidía , Triticum/genética , Regulación hacia Abajo/genética , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Ontología de Genes , Genes de Plantas , Metaboloma , RNA-Seq , Plantones/crecimiento & desarrollo , Factores de Transcripción/metabolismo , Transcripción Genética , Triticum/crecimiento & desarrollo , Triticum/metabolismo , Regulación hacia Arriba/genética
12.
Funct Integr Genomics ; 19(1): 75-90, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30120602

RESUMEN

Oligopeptide transporters (OPT) are integral cell membrane proteins that play a critical role in the transport of small peptides, secondary amino acids, glutathione conjugates, and mineral uptake. In the present study, 67 putative wheat yellow stripe-like transporter (YSL) proteins belonging to the subfamily of OPT transporters were identified. Phylogeny analysis resulted in the distribution of wheat YSLs into four discrete clades. The highest number of YSLs was present on the A genome and the chromosome 2 of hexaploid wheat. The identified wheat YSL genes showed differential expression in different tissues and during grain development suggesting the importance of this subfamily. Gene expression pattern of TaYSLs during iron starvation experiments suggested an early high transcript accumulation of TaYS1A, TaYS1B, TaYSL3, TaYSL5, and TaYSL6 in roots. In contrast, delayed expression was observed in shoots for TaYS1A, TaYS1B, TaYSL5, TaYSL12, and TaYSL19 as compared to control. Further, their expression under biotic and abiotic response emphasized their alternative functions during the plant growth and development. In conclusion, this work is the first comprehensive study of wheat YSL transporters and would be an important resource for prioritizing genes towards wheat biofortification.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Genoma de Planta , Deficiencias de Hierro , Proteínas de Transporte de Membrana/genética , Raíces de Plantas/genética , ARN Mensajero/genética , Triticum/genética , Mapeo Cromosómico , Cromosomas de las Plantas/química , Cromosomas de las Plantas/metabolismo , Regulación del Desarrollo de la Expresión Génica , Ontología de Genes , Transporte Iónico , Proteínas de Transporte de Membrana/clasificación , Proteínas de Transporte de Membrana/metabolismo , Anotación de Secuencia Molecular , Filogenia , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismo , Brotes de la Planta/genética , Brotes de la Planta/crecimiento & desarrollo , Brotes de la Planta/metabolismo , Poliploidía , ARN Mensajero/metabolismo , Estrés Fisiológico , Triticum/clasificación , Triticum/crecimiento & desarrollo , Triticum/metabolismo
13.
Plant Cell Rep ; 38(2): 221-241, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30511183

RESUMEN

KEY MESSAGE: An apple gene, MdDREB76 encodes a functional transcription factor and imparts salinity and drought stress endurance to transgenic tobacco by activating expression of stress-responsive genes. The dehydration-responsive element (DRE)-binding protein (DREB) transcription factors are well known to be involved in regulating abiotic stress-mediated gene expression in plants. In this study, MdDREB76 gene was isolated from apple (Malus x domestica), which encodes a functional transcription factor protein. Overexpression of MdDREB76 in tobacco conferred salt and drought stress tolerance to transgenic lines by inducing antioxidant enzymes, such as superoxide dismutase, ascorbate peroxidase and catalase. The higher membrane stability index, relative water content, proline, total soluble sugar content and lesser H2O2content, electrolyte leakage and lipid peroxidation in transgenics support the improved physiological status of transgenic plants as compared to WT plants under salinity and drought stresses. The MdDREB76 overexpression upregulated the expression of stress-responsive genes that provide salinity and drought stress endurance to the plants. Compared to WT plants, transgenic lines exhibited healthy growth and higher yield under stress conditions. The present study reports MdDREB76 as a key regulator that switches on the battery of downstream genes which impart salt and osmotic stress endurance to the transgenic plants and can be used for genetic engineering of crop plants to combat salinity and drought stresses.


Asunto(s)
Sequías , Regulación de la Expresión Génica de las Plantas , Malus/metabolismo , Nicotiana/fisiología , Proteínas de Plantas/metabolismo , Tolerancia a la Sal/genética , Estrés Fisiológico/genética , Factores de Transcripción/metabolismo , Deshidratación , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Germinación/efectos de los fármacos , Análisis Multivariante , Presión Osmótica , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente , Análisis de Componente Principal , Especies Reactivas de Oxígeno/metabolismo , Tolerancia a la Sal/efectos de los fármacos , Semillas/efectos de los fármacos , Semillas/crecimiento & desarrollo , Cloruro de Sodio/farmacología , Estrés Fisiológico/efectos de los fármacos , Nicotiana/efectos de los fármacos , Nicotiana/genética , Nicotiana/crecimiento & desarrollo , Factores de Transcripción/genética
14.
Sci Rep ; 8(1): 7451, 2018 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-29748645

RESUMEN

Nitrate is the main source of inorganic nitrogen for plants, which also act as signaling molecule. Present study was aimed to understand nitrate regulatory mechanism in Brassica juncea cultivars, with contrasting nitrogen-use-efficiency (NUE) viz. Pusa Bold (PB, high-NUE) and Pusa Jai Kisan (PJK, low-NUE), employing RNA-seq approach. A total of 4031, 3874 and 3667 genes in PB and 2982, 2481 and 2843 genes in PJK were differentially expressed in response to early, low (0.25 mM KNO3), medium (2 mM KNO3) and high (4 mM KNO3) nitrate treatments, respectively, as compared to control (0 mM KNO3). Genes of N-uptake (NRT1.1, NRT1.8, and NRT2.1), assimilation (NR1, NR2, NiR, GS1.3, and Fd-GOGAT) and remobilization (GDH2, ASN2-3 and ALaT) were highly-upregulated in PB than in PJK in response to early nitrate treatments. We have also identified transcription factors and protein kinases that were rapidly induced in response to nitrate, suggesting their involvement in nitrate-mediated signaling. Co-expression network analysis revealed four nitrate specific modules in PB, enriched with GO terms like, "Phenylpropanoid pathway", "Nitrogen compound metabolic process" and "Carbohydrate metabolism". The network analysis also identified HUB transcription factors like mTERF, FHA, Orphan, bZip and FAR1, which may be the key regulators of nitrate-mediated response in B. juncea.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Redes Reguladoras de Genes , Planta de la Mostaza/genética , Nitratos/metabolismo , Nitrógeno/metabolismo , Proteínas de Plantas/genética , Transcriptoma , Planta de la Mostaza/metabolismo , Proteínas de Plantas/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
15.
Bioorg Med Chem Lett ; 28(8): 1417-1422, 2018 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-29463448

RESUMEN

Rhomboids are intramembrane serine proteases with diverse physiological functions in organisms ranging from archaea to humans. Crystal structure analysis has provided a detailed understanding of the catalytic mechanism, and rhomboids have been implicated in various disease contexts. Unfortunately, the design of specific rhomboid inhibitors has lagged behind, and previously described small molecule inhibitors displayed insufficient potency and/or selectivity. Using a computer-aided approach, we focused on the discovery of novel scaffolds with reduced liabilities and the possibility for broad structural variations. Docking studies with the E. coli rhomboid GlpG indicated that 2-styryl substituted benzoxazinones might comprise novel rhomboid inhibitors. Protease in vitro assays confirmed activity of 2-styryl substituted benzoxazinones against GlpG but not against the soluble serine protease α-chymotrypsin. Furthermore, mass spectrometry analysis demonstrated covalent modification of the catalytic residue Ser201, corroborating the predicted mechanism of inhibition and the formation of an acyl enzyme intermediate. In conclusion, 2-styryl substituted benzoxazinones are a novel rhomboid inhibitor scaffold with ample opportunity for optimization.


Asunto(s)
Benzoxazinas/química , Inhibidores de Serina Proteinasa/química , Estirenos/química , Animales , Benzoxazinas/síntesis química , Dominio Catalítico , Bovinos , Quimotripsina/química , Proteínas de Unión al ADN/antagonistas & inhibidores , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/genética , Drosophila/química , Proteínas de Drosophila/metabolismo , Descubrimiento de Drogas , Endopeptidasas/química , Endopeptidasas/genética , Pruebas de Enzimas , Escherichia coli/enzimología , Proteínas de Escherichia coli/antagonistas & inhibidores , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Humanos , Proteínas de la Membrana/antagonistas & inhibidores , Proteínas de la Membrana/química , Proteínas de la Membrana/genética , Simulación del Acoplamiento Molecular , Mutación , Serina/química , Inhibidores de Serina Proteinasa/síntesis química , Estirenos/síntesis química , Factor de Crecimiento Transformador alfa/metabolismo
16.
Biochemistry ; 56(51): 6713-6725, 2017 12 26.
Artículo en Inglés | MEDLINE | ID: mdl-29185711

RESUMEN

Rhomboids are intramembrane serine proteases and belong to the group of structurally and biochemically most comprehensively characterized membrane proteins. They are highly conserved and ubiquitously distributed in all kingdoms of life and function in a wide range of biological processes, including epidermal growth factor signaling, mitochondrial dynamics, and apoptosis. Importantly, rhomboids have been associated with multiple diseases, including Parkinson's disease, type 2 diabetes, and malaria. However, despite a thorough understanding of many structural and functional aspects of rhomboids, potent and selective inhibitors of these intramembrane proteases are still not available. In this study, we describe the computer-based rational design, chemical synthesis, and biological evaluation of novel N-methylene saccharin-based rhomboid protease inhibitors. Saccharin inhibitors displayed inhibitory potency in the submicromolar range, effectiveness against rhomboids both in vitro and in live Escherichia coli cells, and substantially improved selectivity against human serine hydrolases compared to those of previously known rhomboid inhibitors. Consequently, N-methylene saccharins are promising new templates for the development of rhomboid inhibitors, providing novel tools for probing rhomboid functions in physiology and disease.


Asunto(s)
Diseño de Fármacos , Sacarina/análogos & derivados , Serina Proteasas/metabolismo , Inhibidores de Serina Proteinasa/farmacología , Diseño Asistido por Computadora , Células HEK293 , Humanos , Proteínas de la Membrana , Sacarina/farmacología , Inhibidores de Serina Proteinasa/química
17.
Risk Anal ; 37(6): 1063-1071, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-27088758

RESUMEN

Measles is a leading cause of child mortality, and reduction of child mortality is a key Millennium Development Goal. In 2014, the World Health Organization and the U.S. Centers for Disease Control and Prevention developed a measles programmatic risk assessment tool to support country measles elimination efforts. The tool was pilot tested in the State of Uttarakhand in August 2014 to assess its utility in India. The tool assessed measles risk for the 13 districts of Uttarakhand as a function of indicator scores in four categories: population immunity, surveillance quality, program delivery performance, and threat. The highest potential overall score was 100. Scores from each category were totaled to assign an overall risk score for each district. From this risk score, districts were categorized as low, medium, high, or very high risk. Of the 13 districts in Uttarakhand in 2014, the tool classified one district (Haridwar) as very high risk and three districts (Almora, Champawat, and Pauri Garhwal) as high risk. The measles risk in these four districts was largely due to low population immunity from high MCV1-MCV2 drop-out rates, low MCV1 and MCV2 coverage, and the lack of a supplementary immunization activity (SIA) within the past three years. This tool can be used to support measles elimination in India by identifying districts that might be at risk for measles outbreaks, and to guide risk mitigation efforts, including strengthening routine immunization services and implementing SIAs.


Asunto(s)
Vacuna Antisarampión/uso terapéutico , Sarampión/prevención & control , Medición de Riesgo , Centers for Disease Control and Prevention, U.S. , Niño , Preescolar , Erradicación de la Enfermedad , Brotes de Enfermedades/prevención & control , Geografía , Humanos , Programas de Inmunización , Incidencia , India , Lactante , Sarampión/epidemiología , Proyectos Piloto , Vigilancia de la Población , Estados Unidos , Vacunación , Organización Mundial de la Salud
18.
PLoS One ; 11(9): e0163061, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27637072

RESUMEN

In plants, several cellular and metabolic pathways interact with each other to regulate processes that are vital for their growth and development. Carbon (C) and Nitrogen (N) are two main nutrients for plants and coordination of C and N pathways is an important factor for maintaining plant growth and development. In the present work, influence of nitrogen and sucrose (C source) on growth parameters and expression of genes involved in nitrogen transport and assimilatory pathways was studied in B. juncea seedlings. For this, B. juncea seedlings were treated with four combinations of C and N source viz., N source alone (-Suc+N), C source alone (+Suc-N), with N and C source (+Suc+N) or without N and C source (-Suc-N). Cotyledon size and shoot length were found to be increased in seedlings, when nitrogen alone was present in the medium. Distinct expression pattern of genes in both, root and shoot tissues was observed in response to exogenously supplied N and C. The presence or depletion of nitrogen alone in the medium leads to severe up- or down-regulation of key genes involved in N-uptake and transport (BjNRT1.1, BjNRT1.8) in root tissue and genes involved in nitrate reduction (BjNR1 and BjNR2) in shoot tissue. Moreover, expression of several genes, like BjAMT1.2, BjAMT2 and BjPK in root and two genes BjAMT2 and BjGS1.1 in shoot were found to be regulated only when C source was present in the medium. Majority of genes were found to respond in root and shoot tissues, when both C and N source were present in the medium, thus reflecting their importance as a signal in regulating expression of genes involved in N-uptake and assimilation. The present work provides insight into the regulation of genes of N-uptake and assimilatory pathway in B. juncea by interaction of both carbon and nitrogen.


Asunto(s)
Carbono/metabolismo , Regulación de la Expresión Génica de las Plantas , Planta de la Mostaza/metabolismo , Nitrógeno/metabolismo , Antocianinas/metabolismo , Clorofila/metabolismo , Genes de Plantas , Planta de la Mostaza/genética , Planta de la Mostaza/crecimiento & desarrollo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sacarosa/administración & dosificación
19.
Front Plant Sci ; 7: 1957, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28083000

RESUMEN

Universal stress proteins (USPs) are known to be expressed in response to various abiotic stresses in a wide variety of organisms, such as bacteria, archaebacteria, protists, algae, fungi, plants, and animals. However, in plants, biological function of most of the USPs still remains obscure. In the present study, Arabidopsis USP gene (AtUSP) showed induction in response to abscisic acid (ABA) and various abiotic stresses viz. heat, dehydration, salt, osmotic, and cold stresses. Additionally, in silico analysis of AtUSP promoter identified several cis-elements responsive to phytohormones and abiotic stresses such as ABRE, ERE, DRE, and HSE, etc. To functionally validate the AtUSP promoter, the 1115 bp region of promoter was characterized under phytohormone and abiotic stress treatments. Deletion analysis of promoter was carried out by cloning the full length promoter (D0) and its three 5' deletion derivatives, D1 (964 bp), D2 (660 bp), and D3 (503 bp) upstream of the ß-glucuronidase (GUS) reporter gene, which were then stably transformed in Arabidopsis plants. The AtUSP promoter (D0) showed minimal activity under non-stress conditions which was enhanced in response to phytohormone treatments (ABA and ACC) and abiotic stresses such as dehydration, heat, cold, salt, and osmotic stresses. The seedlings harboring D1 and D2 deletion fragments showed constitutive GUS expression even under control condition with increased activity almost under all the treatments. However, D3 seedlings exhibited complete loss of activity under control condition with induction under ACC treatment, dehydration, heat, oxidative, salt, and osmotic stresses. Thus, present study clearly showed that AtUSP promoter is highly inducible by phytohormones and multiple abiotic stresses and it can be exploited as stress inducible promoter to generate multi-stress tolerant crops with minimal effects on their other important traits.

20.
PLoS One ; 10(11): e0143645, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26605918

RESUMEN

Abiotic stresses such as salinity, drought and extreme temperatures affect nitrogen (N) uptake and assimilation in plants. However, little is known about the regulation of N pathway genes at transcriptional level under abiotic stress conditions in Brassica juncea. In the present work, genes encoding nitrate transporters (NRT), ammonium transporters (AMT), nitrate reductase (NR), nitrite reductase (NiR), glutamine synthetase (GS), glutamate synthase (GOGAT), glutamate dehydrogenase (GDH), asparagines synthetase (ASN) were cloned from Brassica juncea L. var. Varuna. The deduced protein sequences were analyzed to predict their subcellular localization, which confirmed localization of all the proteins in their respective cellular organelles. The protein sequences were also subjected to conserved domain identification, which confirmed presence of characteristic domains in all the proteins, indicating their putative functions. Moreover, expression of these genes was studied after 1h and 24h of salt (150 mM NaCl), osmotic (250 mM Mannitol), cold (4°C) and heat (42°C) stresses. Most of the genes encoding nitrate transporters and enzymes responsible for N assimilation and remobilization were found to be downregulated under abiotic stresses. The expression of BjAMT1.2, BjAMT2, BjGS1.1, BjGDH1 and BjASN2 was downregulated after 1hr, while expression of BjNRT1.1, BjNRT2.1, BjNiR1, BjAMT2, BjGDH1 and BjASN2 was downregulated after 24h of all the stress treatments. However, expression of BjNRT1.1, BjNRT1.5 and BjGDH2 was upregulated after 1h of all stress treatments, while no gene was found to be upregulated after 24h of stress treatments, commonly. These observations indicate that expression of most of the genes is adversely affected under abiotic stress conditions, particularly under prolonged stress exposure (24h), which may be one of the reasons of reduction in plant growth and development under abiotic stresses.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Planta de la Mostaza/genética , Planta de la Mostaza/metabolismo , Nitrógeno/metabolismo , Estrés Fisiológico , Transporte Biológico , Clonación Molecular , Regulación Enzimológica de la Expresión Génica , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Dominios y Motivos de Interacción de Proteínas , Transporte de Proteínas
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