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1.
Am J Med Genet A ; 191(10): 2508-2517, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37353954

RESUMO

TBCK-related encephalopathy is a rare pediatric neurodegenerative disorder caused by biallelic loss-of-function variants in the TBCK gene. After receiving anecdotal reports of neurologic phenotypes in both human and mouse TBCK heterozygotes, we quantified if TBCK haploinsufficiency causes a phenotype in mice and humans. Using the tbck+/- mouse model, we performed a battery of behavioral assays and mTOR pathway analysis to investigate potential alterations in neurophysiology. We conducted as well a phenome-wide association study (PheWAS) analysis in a large adult biobank to determine the presence of potential phenotypes associated to this variant. The tbck+/- mouse model demonstrates a reduction of exploratory behavior in animals with significant sex and genotype interactions. The concurrent PheWAS analysis of 10,900 unrelated individuals showed that patients with one copy of a TBCK loss-of-function allele had a significantly higher rate of acquired toe and foot deformities, likely indicative of a mild peripheral neuropathy phenotype. This study presents an example of what may be the underappreciated occurrence of mild neurogenic symptoms in heterozygote individuals of recessive neurogenetic syndromes.


Assuntos
Encefalopatias , Proteínas Serina-Treonina Quinases , Humanos , Criança , Animais , Camundongos , Proteínas Serina-Treonina Quinases/genética , Heterozigoto , Síndrome , Encefalopatias/genética , Fenótipo
2.
Org Biomol Chem ; 21(31): 6243-6262, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37486601

RESUMO

The Morita-Baylis-Hillman (MBH) and Rauhut-Currier (RC) adducts of nitroalkenes are important synthetic intermediates in organic synthesis. This review discusses the applications of different MBH and RC adducts of nitroalkenes such as MBH alcohols, acetates, bromides and hydrazinonitroalkenes as well as ketoalkylnitroalkenes in the synthesis of complex molecules including carbocycles and heterocycles. It also covers the mechanistic aspects, including the key intermediates and the reaction pathways. Early reports on MBH and RC reactions of nitroalkenes and applications of the products were covered in previous reviews. The present review covers the reports that appeared in the timeline of 2015-2023.

3.
Adv Exp Med Biol ; 1412: 175-195, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37378767

RESUMO

Maharashtra was severely affected during the noxious second wave of COVID-19, with the highest number of cases recorded across India. The emergence of new symptoms and dysregulation of multiple organs resulted in high disease severity during the second wave which led to increased difficulties in understanding the molecular mechanisms behind the disease pathology. Exploring the underlying factors can help to relieve the burden on the medical communities to some extent by prioritizing the patients and, at the same time, opening avenues for improved treatments. In the current study, we have performed a mass-spectrometry-based proteomic analysis to investigate the disease pathology using nasopharyngeal swab samples collected from the COVID-19 patients in the Mumbai region of Maharashtra over the period of March-June 2021, the peak of the second wave. A total of 59 patients, including 32 non-severe and 27 severe cases, were considered for this proteomic study. We identified 23 differentially regulated proteins in severe patients as a host response to infection. In addition to the previously identified innate mechanisms of neutrophil and platelet degranulation, this study revealed significant alterations of anti-microbial peptide pathways in severe conditions, illustrating its role in the severity of the infectious strain of COVID-19 during the second wave. Furthermore, myeloperoxidase, cathepsin G, and profilin-1 were identified as potential therapeutic targets of the FDA-approved drugs dabrafenib, ZINC4097343, and ritonavir. This study has enlightened the role of the anti-microbial peptide pathway associated with the second wave in India and proposed its importance in potential therapeutics for COVID-19.


Assuntos
COVID-19 , Humanos , SARS-CoV-2 , Proteômica/métodos , Índia/epidemiologia , Ritonavir
4.
Rev Panam Salud Publica ; 47: e63, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37082536

RESUMO

Objective: To assess the compliance in secondary and tertiary level hospitals with monthly reporting of antibiotic consumption to the Colombian National Public Health Surveillance System (SIVIGILA-INS), and to describe reported antibiotic consumption during 2018-2020. Methods: This study involved a secondary analysis of antibiotic consumption data reported to SIVIGILA-INS. Frequency of hospital reporting was assessed and compared against expected reports, disaggregated by intensive care units (ICU)/non-ICU wards and geographical regions. Consumption was expressed as defined daily dose (DDD) per 100 occupied beds for seven antibiotics. Results: More than 70% of hospitals reported antibiotic consumption at least once in each of the three years (79% in ICU and 71% in non-ICU wards). Of these, ICU monthly reporting was complete (12 monthly reports per year) for 59% in the period 2018-2019 but only 4% in 2020. Non-ICU reporting was complete for 52% in 2019 and for 2% in 2020. Most regions had an overall decrease in reporting in 2020. Analysis of antibiotic consumption showed an increase for piperacillin/tazobactam, ertapenem, and cefepime from 2019 to 2020. Conclusions: There were gaps in the consistency and frequency of reporting. Efforts are needed to improve compliance with monthly reporting, which declined in 2020, possibly due to the COVID-19 pandemic. Non-compliance on reporting and data quality issues should be addressed with the hospitals to enable valid interpretation of antibiotic consumption trends.

5.
Rev Panam Salud Publica ; 47: e15, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37082534

RESUMO

Objective: To describe antimicrobial resistance profiles of Escherichia coli and Salmonella spp. isolated from chicken carcasses and the antimicrobials commonly used in animals in Ecuador and provide information on antimicrobial resistance patterns for implementing evidence-based corrective measures. Methods: Meat samples were collected from chicken carcasses in 199 slaughterhouses across Ecuador as part of a national pilot study for monitoring antimicrobial resistance in agricultural sources in 2019. Samples were tested for E. coli and Salmonella spp. Sensitivity to 10 critically important and three highly important antimicrobials (from a human health perspective) was assessed. The country report submitted to the World Organization for Animal Health was accessed to extract the quantity of antimicrobials produced or imported for use in animals. Results: Of 383 samples, E. coli was isolated from 148 (39%) and Salmonella spp. from 20 (5%) samples. Ninety percent of the isolates were resistant to at least one critically important antimicrobial. Resistance was highest to erythromycin (E. coli 76%; Salmonella spp. 85%) and tetracycline (E. coli 71%; Salmonella spp. 90%). Critically or highly important antimicrobials (colistin, tetracycline, trimethoprim/sulfamethoxazole) formed the bulk (87%) of antimicrobials used in animals as per the World Organization for Animal Health report. Conclusions: High prevalence of antimicrobial resistance in poultry in Ecuador calls for the development of guidelines and regulations on the use of antimicrobials and for engagement with livestock producers. The existing surveillance system needs to be strengthened to improve the monitoring of antimicrobial use and evolving resistance patterns.

6.
Am J Med Genet A ; 188(9): 2772-2776, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35491958

RESUMO

MYH7, encoding the myosin heavy chain sarcomeric ß-myosin heavy chain, is a common cause of both hypertrophic and dilated cardiomyopathy. Additionally, families with left ventricular noncompaction cardiomyopathy (LVNC) and congenital heart disease (CHD), typically septal defects or Ebstein anomaly, have been identified to have heterozygous pathogenic variants in MHY7. One previous case of single ventricle CHD with heart failure due to a MYH7 variant has been identified. Herein, we present a single center's experience of complex CHD due to MYH7 variants. Three probands with a history of CHD, LVNC, and/or arrhythmias were identified to have MYH7 variants through multigene panel testing or exome sequencing. These three patients collectively had 12 affected family members, four with a history of Ebstein anomaly and seven with a history of LVNC. These findings suggest a wider phenotypic spectrum in MYH7-related CHD than previously understood. Further investigation into the possible role of MYH7 in CHD and mechanism of disease is necessary to fully delineate the phenotypic spectrum of MYH7-related cardiac disease. MYH7 should be considered for families with multiple individuals with complex CHD in the setting of a family history of LVNC or arrhythmias.


Assuntos
Cardiomiopatias , Anomalia de Ebstein , Cardiopatias Congênitas , Arritmias Cardíacas/complicações , Arritmias Cardíacas/genética , Miosinas Cardíacas/genética , Cardiomiopatias/etiologia , Cardiopatias Congênitas/complicações , Cardiopatias Congênitas/genética , Humanos , Mutação , Cadeias Pesadas de Miosina/genética
7.
Mycopathologia ; 187(4): 355-362, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35727491

RESUMO

BACKGROUND: In experimental models, the expression of glucose-regulated protein 78 (GRP78) in endothelial cells played a role in the pathogenesis of mucormycosis. However, the role of GRP78 in COVID-19-associated mucormycosis (CAM) has not been studied. We hypothesized that serum GRP78 levels are elevated in subjects with CAM. OBJECTIVE: To compare the serum GRP78 levels in subjects with CAM and COVID-19 controls without mucormycosis. DESIGN AND SETTING: We performed a hospital-based, case-control study between 1 April 2021 and 31 May 2021. PARTICIPANTS: We enrolled 24 subjects each of CAM and COVID-19 subjects without mucormycosis. We also measured serum GRP78 levels in ten healthy controls. EXPOSURE: The primary exposure studied was serum GRP78 concentration, estimated using a commercially available ELISA kit in stored serum samples. RESULTS: We found the mean ± standard deviation (SD) serum GRP78 levels significantly higher (p = 0.0001) among the CAM (374.3 ± 127.3 pg/mL) than the COVID-19 (246.4 ± 67.0 pg/mL) controls. The proportion of subjects with an abnormal GRP78 level (> mean [184.8 pg/mL] plus two SD [23.2 pg/mL] of GRP78 from healthy participants) was 87.5% and 45.8% in the CAM group and COVID-19 controls, respectively. Serum GRP78 level was independently associated with CAM (odds ratio 1.011; 95% confidence interval [1.002-1.019]) after adjusting for diabetes mellitus and hypoxemia during acute COVID-19. CONCLUSION: Serum GRP78 levels were significantly higher in CAM than in COVID-19 controls. Further studies are required to the role of GRP78 in the pathogenesis of CAM.


Assuntos
COVID-19 , Mucormicose , Estudos de Casos e Controles , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Glucose/metabolismo , Proteínas de Choque Térmico/metabolismo , Humanos , Mucormicose/patologia
8.
Environ Res ; 196: 110417, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33217433

RESUMO

INTRODUCTION: Enteric Fever (EF) affects over 14.5 million people every year globally, with India accounting for the largest share of this burden. The water-borne nature of the disease makes it prone to be influenced as much by unsanitary living conditions as by climatic factors. The detection and quantification of the climatic effect can lead to improved public health measures which would in turn reduce this burden. METHODOLOGY: We obtained a list of monthly Widal positive EF cases from 1995 to 2017 from Ahmedabad and Surat Municipalities. We obtained population data, daily weather data, and Oceanic Niño Index values from appropriate sources. We quantified the association between extreme weather events, phases of El Niño Southern Oscillations (ENSO) and incidence of EF. RESULTS: Both cities showed a seasonal pattern of EF, with cases peaking in early monsoon. Risk of EF was affected equally in both cities by the monsoon season -- Ahmedabad (35%) and Surat (34%). Extreme precipitation was associated with 5% increase in EF in Ahmedabad but not in Surat. Similarly, phases of ENSO had opposite effects on EF across the two cities. In Ahmedabad, strong El Niño months were associated with 64% increase in EF risk while strong La Niña months with a 41% reduction in risk. In Surat, strong El Niño was associated with 25% reduction in risk while moderate La Niña with 21% increase in risk. CONCLUSIONS: Our results show that the risk of EF incidence in Gujarat is highly variable, even between the two cities only 260 kms apart. In addition to improvements in water supply and sewage systems, preventive public health measures should incorporate variability in risk across season and phases of ENSO. Further studies are needed to characterize nationwide heterogeneity in climate-mediated risk, and to identify most vulnerable populations that can benefit through early warning systems.


Assuntos
Clima Extremo , Febre Tifoide , El Niño Oscilação Sul , Humanos , Incidência , Índia/epidemiologia , Tempo (Meteorologia)
9.
Biomed Chromatogr ; 35(6): e5065, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33450076

RESUMO

Diabetes is a metabolic disorder characterized by the presence of elevated glucose in the blood and enhanced oxidative stress. It affects the cellular homeostasis that leads to the development of micro-and macro-vascular complications. Monocytes are the primary immune cells present in the circulatory system. Under high-glucose conditions, the cells undergo oxidative stress and secrete reactive oxygen species. The enhanced release of reactive species is known to modify biomolecules like proteins and nucleic acids. Protein carbonylation, one of the most harmful and irreversible protein modifications, is considered as a key player in the progression of diabetes and associated complications. Hence, the present study explores the identification of carbonylated proteins from the monocytes under diabetic stress and determination of their site of modification. Combined avidin affinity chromatography and bottom-up proteomics experiments identified 13 consistently expressed carbonylated proteins. Most of the identified proteins were reported to have altered functions under diabetic conditions that contribute to the development of diabetes-associated inflammation and complications. We were able to determine oxidative stress-induced modifications on Lys, Val, Ile, Cys, Thr and Asp residues.


Assuntos
Diabetes Mellitus/metabolismo , Monócitos , Estresse Oxidativo/efeitos dos fármacos , Carbonilação Proteica/efeitos dos fármacos , Aminoácidos/análise , Aminoácidos/química , Aminoácidos/metabolismo , Cromatografia de Afinidade , Glucose/farmacologia , Humanos , Espectrometria de Massas , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/química , Espécies Reativas de Oxigênio/metabolismo , Células THP-1
10.
J Nat Prod ; 83(7): 2178-2190, 2020 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-32584573

RESUMO

The versatility of the natural products (2S,3S)- and (2S,3R)-3-hydroxy-5-oxotetrahydrofuran-2,3-dicarboxylic acids (1 and 2), isolated in large amounts from tropical plant sources, has been demonstrated by the construction of 3-substituted and 3,4-disubstituted chiral pyrrolidine-2,5-diones. The absolute configurations of chiral pyrrolidine-2,5-diones have been ascertained using chiroptical spectroscopic methods and/or single-crystal XRD data. A combination of different reaction strategies delivering a diverse matrix of fused heterocyclic ring systems is presented. The pyrrolo[2,1-a]isoquinoline alkaloid (+)-crispine A possesses a wide range of pharmacological activities including antidepressant, antiplatelet, antileukemic, and anticancer activities. The analogues of indolizino[8,7-b]indole alkaloids (+)- and (-)-harmicine show strong antileishmanial, antinociceptive, PDE5-inhibitory, antimalarial, and antiviral activities. The bicyclic furo[2,3-b]pyrrolo skeleton is present in many natural products. Thus, the uniqueness of relatively cheap, naturally occurring chiral 2-hydroxycitric acid lactones as chirons has been demonstrated by the construction of some important molecular skeletons that are otherwise difficult to synthesize.


Assuntos
Produtos Biológicos/química , Pirrolidinas/química , Pirrolidinas/farmacologia , Estrutura Molecular , Estereoisomerismo
11.
Circ Res ; 120(7): 1103-1115, 2017 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-28219977

RESUMO

RATIONALE: It is unknown whether every ventricular myocyte expresses all 5 of the cardiac adrenergic receptors (ARs), ß1, ß2, ß3, α1A, and α1B. The ß1 and ß2 are thought to be the dominant myocyte ARs. OBJECTIVE: Quantify the 5 cardiac ARs in individual ventricular myocytes. METHODS AND RESULTS: We studied ventricular myocytes from wild-type mice, mice with α1A and α1B knockin reporters, and ß1 and ß2 knockout mice. Using individual isolated cells, we measured knockin reporters, mRNAs, signaling (phosphorylation of extracellular signal-regulated kinase and phospholamban), and contraction. We found that the ß1 and α1B were present in all myocytes. The α1A was present in 60%, with high levels in 20%. The ß2 and ß3 were detected in only ≈5% of myocytes, mostly in different cells. In intact heart, 30% of total ß-ARs were ß2 and 20% were ß3, both mainly in nonmyocytes. CONCLUSION: The dominant ventricular myocyte ARs present in all cells are the ß1 and α1B. The ß2 and ß3 are mostly absent in myocytes but are abundant in nonmyocytes. The α1A is in just over half of cells, but only 20% have high levels. Four distinct myocyte AR phenotypes are defined: 30% of cells with ß1 and α1B only; 60% that also have the α1A; and 5% each that also have the ß2 or ß3. The results raise cautions in experimental design, such as receptor overexpression in myocytes that do not express the AR normally. The data suggest new paradigms in cardiac adrenergic signaling mechanisms.


Assuntos
Miócitos Cardíacos/metabolismo , Receptores Adrenérgicos alfa/metabolismo , Receptores Adrenérgicos beta/metabolismo , Animais , Células Cultivadas , Ventrículos do Coração/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores Adrenérgicos alfa/genética , Receptores Adrenérgicos beta/genética , Análise de Célula Única
13.
Hum Brain Mapp ; 39(7): 3058-3071, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29582505

RESUMO

In vivo morphological study of the human habenula, a pair of small epithalamic nuclei adjacent to the dorsomedial thalamus, has recently gained significant interest for its role in reward and aversion processing. However, segmenting the habenula from in vivo magnetic resonance imaging (MRI) is challenging due to the habenula's small size and low anatomical contrast. Although manual and semi-automated habenula segmentation methods have been reported, the test-retest reproducibility of the segmented habenula volume and the consistency of the boundaries of habenula segmentation have not been investigated. In this study, we evaluated the intra- and inter-site reproducibility of in vivo human habenula segmentation from 3T MRI (0.7-0.8 mm isotropic resolution) using our previously proposed semi-automated myelin contrast-based method and its fully-automated version, as well as a previously published manual geometry-based method. The habenula segmentation using our semi-automated method showed consistent boundary definition (high Dice coefficient, low mean distance, and moderate Hausdorff distance) and reproducible volume measurement (low coefficient of variation). Furthermore, the habenula boundary in our semi-automated segmentation from 3T MRI agreed well with that in the manual segmentation from 7T MRI (0.5 mm isotropic resolution) of the same subjects. Overall, our proposed semi-automated habenula segmentation showed reliable and reproducible habenula localization, while its fully-automated version offers an efficient way for large sample analysis.


Assuntos
Habenula/anatomia & histologia , Imageamento por Ressonância Magnética/métodos , Neuroimagem/métodos , Adulto , Feminino , Habenula/diagnóstico por imagem , Humanos , Masculino , Adulto Jovem
14.
Anesth Analg ; 125(5): 1616-1626, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28806206

RESUMO

BACKGROUND: Evaluation and treatment of chronic pain worldwide are limited by the lack of standardized assessment tools incorporating consistent definitions of pain chronicity and specific queries of known social and psychological risk factors for chronic pain. The Vanderbilt Global Pain Survey (VGPS) was developed as a tool to address these concerns, specifically in the low- and middle-income countries where global burden is highest. METHODS: The VGPS was developed using standardized and cross-culturally validated metrics, including the Brief Pain Inventory and World Health Organization Disability Assessment Scale, as well as the Pain Catastrophizing Scale, the Fibromyalgia Survey Questionnaire along with queries about pain attitudes to assess the prevalence of chronic pain and disability along with its psychosocial and emotional associations. The VGPS was piloted in both Nepal and India over a 1-month period in 2014, allowing for evaluation of this tool in 2 distinctly diverse cultures. RESULTS: Prevalence of chronic pain in Nepal and India was consistent with published data. The Nepali cohort displayed a pain point prevalence of 48%-50% along with some form of disability present in approximately one third of the past 30 days. Additionally, 11% of Nepalis recorded pain in 2 somatic sites and 39% of those surveyed documented a history of a traumatic event. In the Indian cohort, pain point prevalence was approximately 24% to 41% based on the question phrasing, and any form of disability was present in 6 of the last 30 days. Of the Indians surveyed, 11% reported pain in 2 somatic sites, with only 4% reporting a previous traumatic event. Overall, Nepal had significantly higher chronic pain prevalence, symptom severity, widespread pain, and self-reported previous traumatic events, yet lower reported pain severity. CONCLUSIONS: Our findings confirm prevalent chronic pain, while revealing pertinent cultural differences and survey limitations that will inform future assessment strategies. Specific areas for improvement identified in this VGPS pilot study included survey translation methodology, redundancy of embedded metrics and cultural limitations in representative sampling and in detecting the prevalence of mental health illness, catastrophizing behavior, and previous traumatic events. International expert consensus is needed.


Assuntos
Dor Crônica/epidemiologia , Atividades Cotidianas , Adulto , Sensibilização do Sistema Nervoso Central , Dor Crônica/diagnóstico , Dor Crônica/fisiopatologia , Dor Crônica/psicologia , Efeitos Psicossociais da Doença , Características Culturais , Avaliação da Deficiência , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Nível de Saúde , Inquéritos Epidemiológicos , Humanos , Comportamento de Doença , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Nepal/epidemiologia , Medição da Dor , Percepção da Dor , Projetos Piloto , Prevalência , Adulto Jovem
15.
J Basic Microbiol ; 56(11): 1159-1172, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27160506

RESUMO

An endophytic bacterial strain from a marine green alga, Ulva lactuca, was isolated and identified by 16S rRNA gene sequencing method. The bacterial isolate was found to secrete two major families of cyclic depsilipopeptides, surfactins, and fengycins. Sequencing of the isolated lipopeptides was carried out using the MSn data obtained from an electrospray ionization (ESI) ion trap mass spectrometer coupled to an HPLC system. The assigned sequences were confirmed by a chemical derivatization approach involving esterification followed by mass spectrometric analysis. Distinction of leucine residues from isoleucine was established through a combined electron transfer dissociation-collision-induced dissociation (ETD-CID) method. The fengycins described in this study were found to cause significant delay of growth of two plants, Vigna radiata (mung bean) and Oryza sativa (rice). To the best of our knowledge, this is the first study describing identification and characterization of cyclic peptides from an endophytic Bacillus sp. isolated from marine algae.


Assuntos
Bacillus/metabolismo , Lipopeptídeos/química , Peptídeos Cíclicos/química , Tensoativos/química , Bacillus/genética , Bacillus/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Endófitos/isolamento & purificação , Biblioteca Gênica , Genes de RNAr , Lipopeptídeos/isolamento & purificação , Lipopeptídeos/metabolismo , Lipopeptídeos/farmacologia , Oryza/efeitos dos fármacos , Oryza/crescimento & desenvolvimento , Peptídeos Cíclicos/isolamento & purificação , Peptídeos Cíclicos/metabolismo , Peptídeos Cíclicos/farmacologia , RNA Ribossômico 16S , Espectrometria de Massas por Ionização por Electrospray , Tensoativos/isolamento & purificação , Ulva/microbiologia , Vigna/efeitos dos fármacos , Vigna/crescimento & desenvolvimento
16.
Analyst ; 140(1): 204-12, 2015 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-25365824

RESUMO

We describe two alternative and complementary purification methods for halorhodopsin and bacteriorhodopsin. The first relies on a unique form of detergent micelles which we have called engineered-micelles. These are specifically conjugated in the presence of [hydrophobic chelator:Fe(2+)] complexes and form detergent aggregates into which membrane proteins partition, but hydrophilic water-soluble proteins do not. The approach was tested on the membrane protein, bacteriorhodopsin (bR), with five non-ionic detergents (OG, OTG, NG, DM, and DDM), commonly used in purification and crystallization of membrane proteins, in combination with the commercially available bathophenanthroline or with one of the three synthesized phenanthroline derivatives (Phen-C10, Phen-C8 and Phen-C6). Our results show that bR is extracted efficiently (60-86%) and directly from its native membrane into diverse detergent aggregates with preservation of its native conformation, while 90-95% of an artificial contaminating background is excluded. For implementation of the second method, based on engineered-membranes, the use of detergents, which in some cases may produce protein denaturation, is not required at all. Protein-containing membranes are conjugated via the same hydrophobic [chelator:metal ion] complexes but maintain the membrane protein in its native bilayer environment throughout the process. This method is demonstrated on the membrane protein halorhodopsin from Natronomonas pharaonis (phR) and leads to good recovery yields (74-89%) and removal of >85% of artificial background impurities while preserving the native state of phR. The detailed structure of the hydrophobic chelator used has been found to have a marked effect on the purity and yield of both methods.


Assuntos
Bacteriorodopsinas/isolamento & purificação , Detergentes/química , Halorrodopsinas/isolamento & purificação , Engenharia de Proteínas , Micelas
17.
Arch Microbiol ; 196(3): 179-91, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24493292

RESUMO

Methanococcus maripaludis is a stringently anaerobic archaeon with two studied surface structures, archaella and type IV pili. Previously, it was shown that three pilin genes (mmp0233 [epdA], mmp0236 [epdB] and mmp0237 [epdC]) located within an 11 gene cluster in the genome were necessary for normal piliation. This study focused on analysis of the remaining genes to determine their potential involvement in piliation. Reverse transcriptase PCR experiments demonstrated the 11 genes formed a single transcriptional unit. Deletions were made in all the non-pilin genes except mmp0231. Electron microscopy revealed that all the genes in the locus except mmp0235 and mmp0238 were essential for piliation. Complementation with a plasmid-borne wild-type copy of the deleted gene restored at least some piliation. We identified genes for an assembly ATPase and two versions of the conserved pilin platform forming protein necessary for pili assembly at a separate genetic locus.


Assuntos
Proteínas de Fímbrias/genética , Proteínas de Fímbrias/metabolismo , Mathanococcus/genética , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/metabolismo , Membrana Celular/genética , Sequência Conservada/genética , Deleção de Genes , Teste de Complementação Genética , Mathanococcus/enzimologia , Mathanococcus/ultraestrutura , Óperon/genética , Plasmídeos/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
OMICS ; 28(4): 170-181, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38621149

RESUMO

With their unusually large genome and particle sizes, giant viruses (GVs) defy the conventional definition of viruses. Although most GVs isolated infect unicellular protozoans, such as amoeba, studies in the last decade have established their much wider prevalence infecting most eukaryotic supergroups and some giant viral families with the potential to be human pathogens. Their complexity, almost autonomous life cycle, and enigmatic evolution necessitate the study of GVs. The accurate assessment of GV proteome is a veritable challenge. We have compared the coverage of global protein identification using different methods for GVs isolated in Mumbai, Mimivirus Bombay (MVB), Powai Lake Megavirus (PLMV), and Kurlavirus (KV), along with two previously studied GVs, Acanthamoeba polyphaga Mimivirus (APMV) and Marseillevirus (MV). Our study shows that the simultaneous use of in-gel and in-solution digestion methods can significantly increase the coverage of protein identification in the global proteome analysis of purified GV particles. Combining the two methods of analyses, we identified an additional 72 proteins in APMV and 114 in MV compared with what have been previously reported. Similarly, proteomes of MVB, PLMV, and KV were analyzed, and a total of 242 proteins in MVB, 287 proteins in PLMV, and 174 proteins in KV were identified. Our results suggest that a combined methodology of in-gel and in-solution methods is more efficient and opens up new avenues for innovation in global proteome analysis of GVs. Future planetary health research on GVs can benefit from consideration of a broader range of proteomics methodologies as illustrated by the present study.


Assuntos
Vírus Gigantes , Proteoma , Proteômica , Proteômica/métodos , Vírus Gigantes/genética , Vírus Gigantes/metabolismo , Proteínas Virais/metabolismo
19.
Cureus ; 16(6): e62613, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39027767

RESUMO

BACKGROUND: Despite the vast research by nursing professionals on various methods of nursing education, little research has been conducted exploring the efficacy of peer learning as a teaching-learning tool amongst registered nurses. Hence, this study was conducted among in-service nursing officers to evaluate the usefulness of simulation-based peer learning sessions as an educational tool for capacity building. MATERIAL AND METHODS: Using a pre-test and post-test design, the study was conducted among 150 in-service nurses at a tertiary care hospital. Five structured simulation-based, peer learning modules were designed. The nurses were divided into five groups using random and purposive sampling. Each group attended one session of the peer learning module on advanced nursing care by simulated clinical and nursing care 'demonstrate, observe, assist, and perform' (DOAP) activity. Pre-test, post-test, and retention tests (after two months) were conducted, and the results were compared. RESULTS: There was a significant increase in mean knowledge (p-value < 0.05) in the post-test after all five sessions, which shows the effectiveness of such peer learning sessions in improving the baseline. There was a decline in mean scores in the retention test compared to that of the post-test, which was statistically significant in only the group of learners participating in the first session. CONCLUSION: The study provides substantial evidence that simulation-based peer learning is an effective tool for continuing nursing education, and it can be used as a valuable tool to reduce the documented theory-practice gap.

20.
F1000Res ; 13: 642, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39290845

RESUMO

Background: Traditionally in the Democratic Republic of the Congo (DRC), centralised Ebola treatment centres (ETCs) have been set exclusively for Ebola virus disease (EVD) case management during outbreaks. During the 2020 EVD outbreak in DRC's Equateur Province, existing health centres were equipped as decentralised treatment centres (DTC) to improve access for patients with suspected EVD. Between ETCs and DTCs, we compared the time from symptom onset to admission and diagnosis among patients with suspected EVD. Methods: This was a cohort study based on analysis of a line-list containing demographic and clinical information of patients with suspected EVD admitted to any EVD health facility during the outbreak. Results: Of 2359 patients with suspected EVD, 363 (15%) were first admitted to a DTC. Of 1996 EVD-suspected patients initially admitted to an ETC, 72 (4%) were confirmed as EVD-positive. Of 363 EVD-suspected patients initially admitted to a DTC, 6 (2%) were confirmed and managed as EVD-positive in the DTC. Among all EVD-suspected patients, the median (interquartile range) duration between symptom onset and admission was 2 (1-4) days in a DTC compared to 4 (2-7) days in an ETC (p<0.001). Similarly, time from symptom onset to admission was significantly shorter among EVD-suspected patients ultimately diagnosed as EVD-negative. Conclusions: Since <5% of the EVD-suspected patients admitted were eventually diagnosed with EVD, there is a need for better screening to optimise resource utilization and outbreak control. Only one in seven EVD-suspected patients were admitted to a DTC first, as the DTCs were piloted in a limited and phased manner. However, there is a case to be made for considering decentralized care especially in remote and hard-to-reach areas in places like the DRC to facilitate early access to care, contain viral shedding by patients with EVD and ensure no disrupted provision of non-EVD services.


Assuntos
Surtos de Doenças , Doença pelo Vírus Ebola , Humanos , República Democrática do Congo/epidemiologia , Doença pelo Vírus Ebola/epidemiologia , Doença pelo Vírus Ebola/terapia , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Adolescente , Adulto Jovem , Estudos de Coortes , Criança , Atenção à Saúde/organização & administração , Ebolavirus
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