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1.
J Biol Chem ; 300(8): 107496, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38925325

RESUMO

Emerging Artemisinin (ART) resistance in Plasmodium falciparum (Pf) poses challenges for the discovery of novel drugs to tackle ART-resistant parasites. Concentrated efforts toward the ART resistance mechanism indicated a strong molecular link of ART resistance with upregulated expression of unfolded protein response pathways involving Prefoldins (PFDs). However, a complete characterization of PFDs as molecular players taking part in ART resistance mechanism, and discovery of small molecule inhibitors to block this process have not been identified to date. Here, we functionally characterized all Pf Prefoldin subunits (PFD1-6) and established a causative role played by PFDs in ART resistance by demonstrating their expression in intra-erythrocytic parasites along with their interactions with Kelch13 protein through immunoprecipitation coupled MS/MS analysis. Systematic biophysical interaction analysis between all subunits of PFDs revealed their potential to form a complex. The role of PFDs in ART resistance was confirmed in orthologous yeast PFD6 mutants, where PfPFD6 expression in yeast mutants reverted phenotype to ART resistance. We identified an FDA-approved drug "Biperiden" that restricts the formation of Prefoldin complex and inhibits its interaction with its key parasite protein substrates, MSP-1 and α-tubulin-I. Moreover, Biperiden treatment inhibits the parasite growth in ART-sensitive Pf3D7 and resistant Pf3D7k13R539T strains. Ring survival assays that are clinically relevant to analyze ART resistance in Pf3D7k13R539T parasites demonstrate the potency of BPD to inhibit the growth of survivor parasites. Overall, our study provides the first evidence of the role of PfPFDs in ART resistance mechanisms and opens new avenues for the management of resistant parasites.

2.
J Membr Biol ; 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38970681

RESUMO

Progesterone (P4) acts as a key conserved signalling molecule in vertebrate reproduction. P4 is especially important for mature sperm physiology and subsequent reproductive success. "CatSpermasome", a multi-unit molecular complex, has been suggested to be the main if not the only P4-responsive atypical Ca2+-ion channel present in mature sperm. Altogether, here we analyse the protein sequences of CatSper1-4 from more than 500 vertebrates ranging from early fishes to humans. CatSper1 becomes longer in mammals due to sequence gain mainly at the N-terminus. Overall the conservation of full-length CatSper1-4 as well as the individual TM regions remain low. The lipid-water-interface residues (i.e. a 5 amino acid stretch sequence present on both sides of each TM region) also remain highly diverged. No specific patterns of amino acid distributions were observed. The total frequency of positively charged, negatively charged or their ratios do not follow in any specific pattern. Similarly, the frequency of total hydrophobic, total hydrophilic residues or even their ratios remain random and do not follow any specific pattern. We noted that the CatSper1-4 genes are missing in amphibians and the CatSper1 gene is missing in birds. The high variability of CatSper1-4 and gene-loss in certain clades indicate that the "CatSpermasome" is not the only P4-responsive ion channel. Data indicate that the molecular evolution of CatSper is mostly guided by diverse hydrophobic ligands rather than only P4. The comparative data also suggest possibilities of other Ca2+-channel/s in vertebrate sperm that can also respond to P4.

3.
Biotechnol Bioeng ; 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38698719

RESUMO

Cultivating cells in shake flasks is a routine operation that is largely unchanged since its inception. A glass or plastic Erlenmeyer vessel with the primary gas exchange taking place across various porous plugs is used with media volumes typically ranging from 100 mL to 2 L. Oxygen limitation and carbon dioxide accumulation in the vessel is a major concern for studies involving shake flask cultures. In this study, we enhance mass transfer in a conventional shake flask by replacing the body wall with a permeable membrane. Naturally occurring concentration gradient across the permeable membrane walls facilitates the movement of oxygen and carbon dioxide between the flask and the external environment. The modified flask called the breathable flask, has shown a 40% improvement in mass transfer coefficient (kLa) determined using the static diffusion method. The prokaryotic cell culture studies performed with Escherichia coli showed an improvement of 28%-66% in biomass and 41%-56% in recombinant product yield. The eukaryotic cell culture study performed with Pichia pastoris expressing proinsulin exhibited a 40% improvement in biomass and 115% improvement in protein yield. The study demonstrates a novel approach to addressing the mass transfer limitations in conventional shake flask cultures. The proposed flask amplifies its value by providing a membrane-diffusion-based sensing platform for the integration of low-cost, noninvasive sensing capabilities for real-time monitoring of critical cell culture parameters like dissolved oxygen and dissolved carbon dioxide.

4.
Langmuir ; 40(29): 14872-14887, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-38995219

RESUMO

Nowadays, the development of clean and green energy sources is the priority interest of research due to increasing global energy demand and extensive usage of fossil fuels, which create pollutants. Hydrogen has the highest energy density by weight among all chemical fuels. For the commercial-scale production of hydrogen, water electrolysis is the best method, which requires an efficient, cost-effective, and earth-abundant electrocatalyst. Recent studies have shown that the 2D Janus transition metal dichalcogenides (JTMDs) are promising materials for use as electrocatalysts and are highly effective for electrocatalytic H2 evolution reaction (HER). Here, we report a 2D monolayer WSeTe JTMD, which is highly effective toward HER. We have studied the electronic properties of 2D monolayer WSeTe JTMD using the periodic hybrid DFT-D method, and a direct electronic band gap of 2.39 eV was obtained. We have explored the HER pathways, mechanisms, and intermediates, including various transition state (TS) structures (Volmer TS, i.e., H*-migration TS, Heyrovsky TS, and Tafel TS) using a molecular cluster model of the subject JTMD noted as W10Se9Te12. The present calculations reveal that the 2D monolayer WSeTe JTMD is a potential electrocatalyst for HER. It has the lowest energy barriers for all the TSs among other TMDs. It has been shown that the Heyrovsky energy barrier (= 8.72 kcal mol-1) in the case of the Volmer-Heyrovsky mechanism is larger than the Tafel energy barrier (= 3.27 kcal mol-1) in the Volmer-Tafel mechanism. Hence, our present study suggests that the formation of H2 is energetically more favorable via the Volmer-Tafel mechanism. This study helps to shed light on the rational design of 2D single-layer JTMD, which is highly effective toward HER, and we expect that the present work can be further extended to other JTMDs to find out the improved electrocatalytic performance.

5.
Mol Biol Rep ; 51(1): 103, 2024 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-38219219

RESUMO

BACKGROUND: Heat stress is known to adversely affect testicular activity and manifest the pathogenesis of spermatogenesis. Morin hydrate is a plant-derived compound, which contains a wide range of biological activities. Thus, it is hypothesized that morin hydrate might have an ameliorative effect on heat-induced testicular impairment. There has not been any research on the impact of morin hydrate on heat-induced testicular damage. METHODS: The experimental mice were divided into four groups, groups1 as the normal control group (CN), and the second which underwent heat stress (HS) by immersing the lower body for 15 min in a thermostatically controlled water bath kept at 43 °C (HS), and third and fourth heat-stressed followed by two different dosages of morin hydrate 10 mg/kg (HSM10) and 100 mg/kg (HSM100) for 14 days. RESULTS: Morin hydrate treatment at 10 mg/kg improved, circulating testosterone levels (increases 3ßHSD), and oxidative stress along with improvement in the testis and caput and corpus epididymis histoarchitecture, however, both doses of morin hydrate improved sperm parameters. Morin hydrate treatment significantly increases germ cell proliferation, (GCNA, BrdU staining), expression of Bcl2 and decreases expression of active caspase 3. Heat stress also decreased the expression of AR, ER- α, and ER-ß, and Morin hydrate treatment increased the expression of these markers in the 10 mg/kg treatment group. CONCLUSION: Morin hydrate ameliorates heat-induced testicular impairment modulating testosterone synthesis, germ cell proliferation, and oxidative stress. These effects could be manifested by regulating androgen and estrogen receptors. However, the two doses showed differential effects of some parameters, which requires further investigations.


Assuntos
Flavonas , Sêmen , Testículo , Masculino , Camundongos , Animais , Testículo/metabolismo , Espermatozoides/metabolismo , Espermatogênese , Estresse Oxidativo , Testosterona/metabolismo
6.
Exp Parasitol ; 257: 108688, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38142765

RESUMO

The recent increase in the drug (liposomal amphotericin-B) unresponsive cases becomes hostile for the visceral leishmaniasis (VL) elimination target. The quest for new antileishmanial drugs is on the way and may demand more time. Meanwhile, drug repurposing is a quite promising option to explore further. We made such an attempt with thioridazine (TRZ), a first-line antipsychotic drug, which was reported for antimicrobial activity. In this study, we evaluated the drug activity of TRZ against amphotericin-B (Amp-B) sensitive and unresponsive Leishmania donovani promastigotes, as well as intracellular amastigotes (drug sensitive). We observed a potent antileishmanial activity of TRZ with significantly low half maximal inhibitory concentrations (IC50) on both the variants of promastigotes (0.61 ± 0.15 µM). These concentrations are comparable to the previously reported IC50 concentration of the current antileishmanial drug (Amp-B) against L. donovani. Light microscopy reveals the perturbations in promastigote morphology upon TRZ treatment. The in vitro studies on human macrophage cell lines determine the 50% cytotoxicity concentration (CC50) of TRZ on host cells as 20.046 µM and a half maximal effective concentration (EC50) as 0.91 µM during L. donovani infection, in turn selectivity index (SI) was calculated as 22.03 µM. Altogether, the results demonstrate that TRZ has the potential for drug repurposing and further studies on animal models could provide better insights for VL treatment.


Assuntos
Antiprotozoários , Leishmania donovani , Leishmaniose Visceral , Animais , Humanos , Anfotericina B/farmacologia , Anfotericina B/uso terapêutico , Tioridazina/farmacologia , Tioridazina/uso terapêutico , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Leishmaniose Visceral/tratamento farmacológico
7.
Exp Parasitol ; 259: 108713, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38350522

RESUMO

The recurrence of visceral leishmaniasis (VL), also called kala-azar (KA), in endemic regions of tropical countries like India, is primarily attributed to asymptomatic VL, post-kala azar dermal leishmaniasis (PKDL), and human immunodeficiency virus (HIV) co-infection. To effectively manage VL cases and elimination targets, an early and rapid diagnosis as well as accurate field surveillance is highly essential. The traditional sampling methods like bone marrow (BM), spleen, and lymph node (LN) tissue aspirations are invasive, painful, tedious, and prone to nosocomial infections, require skilled persons and hospital facilities, and are not feasible in rural areas. Therefore, there is an urgent requirement for the adoption of a patient-friendly, non-invasive, non-hospitalized sampling procedure that ensures an effective VL diagnosis. This review aims to meticulously evaluate the most recent scientific research that focuses on the precision, feasibility, and applicability of non-invasive sampling (NIS) and techniques for the diagnosis and test of cure of VL, particularly in resource-limited settings. Apart from that, the non-invasive techniques (NIT) that have shown promising results while monitoring VL treatment response and relapse are also reviewed. The limitations associated with NIT and possible improvements in this regard are discussed as well to improve the diagnosis and management of VL.


Assuntos
Leishmaniose Cutânea , Leishmaniose Visceral , Humanos , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/tratamento farmacológico , Leishmaniose Visceral/epidemiologia , Leishmaniose Cutânea/diagnóstico , Índia/epidemiologia , Recidiva
8.
Nucleic Acids Res ; 50(12): 7002-7012, 2022 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-35748877

RESUMO

Flexible regions in biomolecular complexes, although crucial to understanding structure-function relationships, are often unclear in high-resolution crystal structures. In this study, we showed that single-molecule techniques, in combination with computational modeling, can characterize dynamic conformations not resolved by high-resolution structure determination methods. Taking two Pif1 helicases (ScPif1 and BsPif1) as model systems, we found that, besides a few tightly bound nucleotides, adjacent solvent-exposed nucleotides interact dynamically with the helicase surfaces. The whole nucleotide segment possessed curved conformations and covered the two RecA-like domains of the helicases, which are essential for the inch-worm mechanism. The synergetic approach reveals that the interactions between the exposed nucleotides and the helicases could be reduced by large stretching forces or electrostatically shielded with high-concentration salt, subsequently resulting in reduced translocation rates of the helicases. The dynamic interactions between the exposed nucleotides and the helicases underlay the force- and salt-dependences of their enzymatic activities. The present single-molecule based approach complements high-resolution structural methods in deciphering the molecular mechanisms of the helicases.


Assuntos
DNA
9.
Curr Issues Mol Biol ; 45(9): 7388-7403, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37754251

RESUMO

In this study, we evaluated gamete quality parameters of mature male koi carp (Cyprinus carpio) exposed to three different concentrations (1, 10, and 100 µg/L) of di-(2-ethylhexyl) phthalate (DEHP). After 60 days of exposure, there was a significant decrease in the gonadosomatic index (GSI) of males exposed to 10 and 100 µg/L of DEHP. Histological analysis of the testes revealed impaired histoarchitecture, including inflammatory cells, intratubular vacuoles, and swollen seminiferous tubules in treatment groups. Gamete quality parameters like sperm production, motility, spermatocrit, and sperm density values were significantly decreased at the 10 and 100 µg/L concentrations. Biochemical compositions, including glucose, cholesterol, and total protein levels, were significantly changed in the treatment groups. Similarly, the ionic compositions of seminal fluid (Na, K, Ca, and Mg) also varied in the treatment groups. Furthermore, the 11-ketotestosterone levels were decreased, and the 17-ß estradiol levels were increased in the DEHP-treated groups. The mRNA expression levels of reproduction-related genes, including Fshr, Lhr, Ar, Erα, and Erß, were significantly changed in the DEHP-treated males in a dose-dependent manner. In conclusion, the findings of this study confirmed that environmentally relevant exposure to DEHP may contribute to a decline in the gamete quality of male fishes.

10.
Plant Biotechnol J ; 21(5): 1005-1021, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36668687

RESUMO

Trees constitute promising renewable feedstocks for biorefinery using biochemical conversion, but their recalcitrance restricts their attractiveness for the industry. To obtain trees with reduced recalcitrance, large-scale genetic engineering experiments were performed in hybrid aspen blindly targeting genes expressed during wood formation and 32 lines representing seven constructs were selected for characterization in the field. Here we report phenotypes of five-year old trees considering 49 traits related to growth and wood properties. The best performing construct considering growth and glucose yield in saccharification with acid pretreatment had suppressed expression of the gene encoding an uncharacterized 2-oxoglutarate-dependent dioxygenase (2OGD). It showed minor changes in wood chemistry but increased nanoporosity and glucose conversion. Suppressed levels of SUCROSE SYNTHASE, (SuSy), CINNAMATE 4-HYDROXYLASE (C4H) and increased levels of GTPase activating protein for ADP-ribosylation factor ZAC led to significant growth reductions and anatomical abnormalities. However, C4H and SuSy constructs greatly improved glucose yields in saccharification without and with pretreatment, respectively. Traits associated with high glucose yields were different for saccharification with and without pretreatment. While carbohydrates, phenolics and tension wood contents positively impacted the yields without pretreatment and growth, lignin content and S/G ratio were negative factors, the yields with pretreatment positively correlated with S lignin and negatively with carbohydrate contents. The genotypes with high glucose yields had increased nanoporosity and mGlcA/Xyl ratio, and some had shorter polymers extractable with subcritical water compared to wild-type. The pilot-scale industrial-like pretreatment of best-performing 2OGD construct confirmed its superior sugar yields, supporting our strategy.


Assuntos
Lignina , Populus , Lignina/metabolismo , Populus/genética , Populus/metabolismo , Madeira/genética , Madeira/metabolismo , Glucose/metabolismo , Engenharia Genética
11.
Microb Cell Fact ; 22(1): 106, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37268947

RESUMO

Biofloc technology aims to maximize fish farming productivity by effectively breaking down ammonia and nitrite, promoting healthy flocculation, and enhancing the growth and immunity of cultured animals. However, a major limitation in this field is the suitable starter microbial culture and narrow number of fish species that have been tested with the biofloc system. Here, we investigated various microbial inoculum containing beneficial microbes with probiotics, immunostimulatory and flocs development and bioremediation properties would lead to the development of ideal biofloc development. Three treatment groups with different microbial combinations, viz., group 1 [Bacillus subtilis (AN1) + Pseudomonas putida (PB3) + Saccharomyces cerevisiae (ATCC-2601)], group 2 [B. subtilis (AN2) + P. fluorescens (PC3) + S. cerevisiae (ATCC-2601)] and group 3 [B. subtilis (AN3) + P. aeruginosa (PA2) + S. cerevisiae (ATCC-2601)] were used and compared with the positive control (pond water without microbial inoculums) and negative control (clear water: without microbial inoculums and carbon sources) on biofloc development and its characteristic features to improve the water quality and growth of fish. We demonstrated that microbial inoculums, especially group 2, significantly improve the water quality and microbiota of flocs and gut of the test animal, Heteropneustes fossilis. The study further demonstrates that biofloc system supplemented with microbial inoculums positively regulates gut histomorphology and growth performance, as evidenced by improved villous morphology, amylase, protease and lipase activity, weight gain, FCR, T3, T4 and IGF1 levels. The inoculums induced an antioxidative response marked by significantly higher values of catalase (CAT) and superoxide dismutase (SOD) activity. Furthermore, the supplementation of microbial inoculums enhances both specific and non-specific immune responses and significantly elevated levels of immune genes (transferrin, interleukin-1ß and C3), and IgM was recorded. This study provides a proof-of-concept approach for assessing microbial inoculums on fish species that can be further utilized to develop biofloc technology for use in sustainable aquaculture.


Assuntos
Peixes-Gato , Saccharomyces cerevisiae , Animais , Suplementos Nutricionais , Imunidade Inata , Aquicultura
12.
Dig Dis Sci ; 68(10): 4050-4059, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37584869

RESUMO

BACKGROUND: Previous studies have demonstrated a disparity in liver transplantation (LT) for hepatocellular carcinoma (HCC) among races in the United States (U.S.). AIMS: We aimed to update the literature on the odds, trends, and complications of LT in the treatment of hepatocellular carcinoma (HCC), among individuals of different racial backgrounds. METHODS: This is a nationwide study of adult individuals admitted for LT with a primary diagnosis of HCC. Using weighted data from the National Inpatient Sample (NIS) database, we compared the odds of LT among different races from 2016 to 2020, using a multivariate regression analysis. We further assessed the trends and outcomes of LT among races. RESULTS: A total of 112,110 adult were hospitalized with a primary diagnosis of HCC. 3020 underwent LT. When compared to Whites, the likelihood of undergoing LT for HCC was significantly reduced in Blacks (OR = 0.60, 95% CI = 0.46-0.78). Further, Blacks had increased mortality rates (7% in Blacks vs. 1% in Whites, p < 0.001), sepsis (11% in Blacks vs. 3% in Whites, p = 0.015), and acute kidney injury (AKI) (54% in Blacks vs. 31% in Whites, p < 0.001) following LT. CONCLUSIONS: Individuals identifying as Blacks were less likely to undergo LT for HCC, and more likely to develop complications. Further initiatives are warranted to mitigate the existing disparities among racial groups.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Transplante de Fígado , Adulto , Humanos , Estados Unidos/epidemiologia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Transplante de Fígado/efeitos adversos , Etnicidade , Grupos Raciais , Estudos Retrospectivos
13.
Dig Dis Sci ; 68(12): 4389-4397, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37815688

RESUMO

INTRODUCTION: Previous research identified AIH as linked to unfavorable obstetrical outcomes in a US nationwide retrospective study from 2012-2016. Our aim is to update the literature and strengthen the AIH-pregnancy outcomes relationship. METHODS: Using the National Inpatient Sample database in the US, from 2016 to 2020, we compared pregnant females with a diagnosis of AIH to those with and without other chronic liver diseases (CLD), using ICD-10-CM codes. Baseline characteristics were analyzed using T-test and Chi-Square, and multivariate regression was used to estimate the differences in maternal outcomes adjusted for age, race, insurance status, geographical location, hospital characteristics, and comorbid conditions. RESULTS: Out of 19,392,328 hospitalizations for pregnant females ≥ 18 years old from 2016 to 2020, 1095 had AIH, 179,655 had CLD, and 19,206,696 had no CLD. No mortality was observed among individuals with AIH. When compared to individuals without CLD, AIH was associated with an 82% increase in the odds of preterm delivery (AIH: 8% vs. Without CLD: 5%, adjusted Odds Ratio = 1.82, 95% CI 1.06-3.14), with no significant differences in gestational diabetes mellitus, hypertensive complications, and postpartum hemorrhage, and a 0.6 day longer hospital stay. Furthermore, there were no significant differences in outcomes between AIH and CLD. CONCLUSIONS: Our study reinforces the association of AIH with adverse obstetrical outcomes (e.g., preterm delivery), however, we found that there is no difference in GDM and hypertensive complications, as suggested in prior studies. Therefore, further investigations are needed to clarify the association between AIH and these obstetrical complications.


Assuntos
Hepatite Autoimune , Hepatopatias , Nascimento Prematuro , Gravidez , Feminino , Recém-Nascido , Humanos , Adolescente , Hepatite Autoimune/diagnóstico , Hepatite Autoimune/epidemiologia , Hepatite Autoimune/complicações , Estudos Retrospectivos , Nascimento Prematuro/epidemiologia , Hepatopatias/complicações , Hospitalização
14.
Clin Infect Dis ; 75(8): 1423-1432, 2022 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-35147680

RESUMO

BACKGROUND: Visceral leishmaniasis (VL) in patients with human immunodeficiency virus (HIV) presents an increasingly important patient cohort in areas where both infections are endemic. Evidence for treatment is sparce, with no high-quality studies from the Indian subcontinent. METHODS: This is a randomized, open-label, parallel-arm, phase 3 trial conducted within a single hospital in Patna, India. One hundred and fifty patients aged ≥18 years with serologically confirmed HIV and parasitologically confirmed VL were randomly allocated to 1 of 2 treatment arms, either a total 40 mg/kg intravenous liposomal amphotericin B (AmBisome; Gilead Pharmaceuticals) administered in 8 equal doses over 24 days or a total 30 mg/kg intravenous AmBisome administered in 6 equal doses given concomitantly with a total 1.4 g oral miltefosine administered through 2 daily doses of 50 mg over 14 days. The primary outcome was intention-to-treat relapse-free survival at day 210, defined as absence of signs and symptoms of VL or, if symptomatic, negative parasitological investigations. RESULTS: Among 243 patients assessed for eligibility, 150 were recruited between 2 January 2017 and 5 April 2018, with no loss to follow-up. Relapse-free survival at day 210 was 85% (64/75; 95% CI, 77-100%) in the monotherapy arm, and 96%, (72/75; 90-100%) in the combination arm. Nineteen percent (28/150) were infected with concurrent tuberculosis, divided equally between arms. Excluding those with concurrent tuberculosis, relapse-free survival at day 210 was 90% (55/61; 82-100%) in the monotherapy and 97% (59/61; 91-100%) in the combination therapy arm. Serious adverse events were uncommon and similar in each arm. CONCLUSIONS: Combination therapy appears to be safe, well tolerated, and effective, and halves treatment duration of current recommendations. CLINICAL TRIALS REGISTRATION: Clinical Trial Registry India (CTRI/2015/05/005807; the protocol is available online at https://osf.io/avz7r).


Assuntos
Antiprotozoários , Coinfecção , Infecções por HIV , Leishmaniose Visceral , Adolescente , Adulto , Anfotericina B , Antiprotozoários/efeitos adversos , Coinfecção/tratamento farmacológico , Quimioterapia Combinada , HIV , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Índia , Leishmaniose Visceral/complicações , Leishmaniose Visceral/tratamento farmacológico , Preparações Farmacêuticas , Fosforilcolina/efeitos adversos , Fosforilcolina/análogos & derivados , Recidiva , Resultado do Tratamento
15.
Clin Infect Dis ; 75(1): e368-e379, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-35323932

RESUMO

BACKGROUND: In locations where few people have received coronavirus disease 2019 (COVID-19) vaccines, health systems remain vulnerable to surges in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. Tools to identify patients suitable for community-based management are urgently needed. METHODS: We prospectively recruited adults presenting to 2 hospitals in India with moderate symptoms of laboratory-confirmed COVID-19 to develop and validate a clinical prediction model to rule out progression to supplemental oxygen requirement. The primary outcome was defined as any of the following: SpO2 < 94%; respiratory rate > 30 BPM; SpO2/FiO2 < 400; or death. We specified a priori that each model would contain three clinical parameters (age, sex, and SpO2) and 1 of 7 shortlisted biochemical biomarkers measurable using commercially available rapid tests (C-reactive protein [CRP], D-dimer, interleukin 6 [IL-6], neutrophil-to-lymphocyte ratio [NLR], procalcitonin [PCT], soluble triggering receptor expressed on myeloid cell-1 [sTREM-1], or soluble urokinase plasminogen activator receptor [suPAR]), to ensure the models would be suitable for resource-limited settings. We evaluated discrimination, calibration, and clinical utility of the models in a held-out temporal external validation cohort. RESULTS: In total, 426 participants were recruited, of whom 89 (21.0%) met the primary outcome; 257 participants comprised the development cohort, and 166 comprised the validation cohort. The 3 models containing NLR, suPAR, or IL-6 demonstrated promising discrimination (c-statistics: 0.72-0.74) and calibration (calibration slopes: 1.01-1.05) in the validation cohort and provided greater utility than a model containing the clinical parameters alone. CONCLUSIONS: We present 3 clinical prediction models that could help clinicians identify patients with moderate COVID-19 suitable for community-based management. The models are readily implementable and of particular relevance for locations with limited resources.


Assuntos
COVID-19 , Adulto , COVID-19/diagnóstico , Progressão da Doença , Humanos , Interleucina-6 , Modelos Estatísticos , Alta do Paciente , Segurança do Paciente , Prognóstico , Estudos Prospectivos , Receptores de Ativador de Plasminogênio Tipo Uroquinase , Reprodutibilidade dos Testes , SARS-CoV-2
16.
Phys Chem Chem Phys ; 24(46): 28283-28294, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36382613

RESUMO

The oxygen reduction reaction (ORR) is an indispensable reaction in electrochemical energy converting systems such as fuel cells. Generally, reaction kinetics of the ORR is slow, and to speed it up, a practical electrocatalyst is needed. Pt-based catalysts are thermodynamically more appropriate, but due to their scarcity and high cost, they cannot be used on a commercial scale in industries. To search for non-noble metal catalysts, we have performed a theoretical study on the CsPbBr3 perovskite material as a potential candidate for the ORR. The 3D bulk crystal structure of CsPbBr3 shows a large electronic band gap (Eg) of around 2.95 eV and it cannot be used as an efficient electrocatalyst for the ORR. We have cleaved a (001) surface from the 3D CsPbBr3 perovskite and computationally designed a 2D monolayer slab structure of the CsPbBr3 material. The present study showed that the 2D monolayer structure of CsPbBr3 has a tiny band gap about 0.22 eV, and hence the 2D monolayer CsPbBr3 perovskite can be used as a cathode material for fuel cell applications. Special priority has been given to the 2D layered perovskite structure to gain insights into its ORR kinetics by employing the first principles-based density functional theory (DFT) method. This study reveals that the basal plane of the 2D CsPbBr3 perovskite exhibits excellent electrocatalytic activity toward the ORR with a four-electron reduction pathway selectivity. Both the dissociative and associative reaction mechanisms of the ORR on the surfaces of the 2D monolayer CsPbBr3 perovskite have been explored by computing the change in Gibb's free energy (ΔG). All the reaction intermediates studied here are thermodynamically favorable and the present study suggests that the ORR follows a 4e- transfer mechanism on the surface of 2D CsPbBr3 and the associative mechanism is favorable over the dissociative mechanism of the ORR. This study provides a theoretical basis for future application of 2D CsPbBr3 perovskite-based electrocatalysts for achieving an effective ORR, indicating that they are promising Pt-free candidates for fuel cell components.

17.
J Biol Chem ; 295(20): 6972-6982, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32265297

RESUMO

The ovarian tumor domain (OTU) deubiquitinylating cysteine proteases OTUB1 and OTUB2 (OTU ubiquitin aldehyde binding 1 and 2) are representative members of the OTU subfamily of deubiquitinylases. Deubiquitinylation critically regulates a multitude of important cellular processes, such as apoptosis, cell signaling, and growth. Moreover, elevated OTUB expression has been observed in various cancers, including glioma, endometrial cancer, ovarian cancer, and breast cancer. Here, using molecular dynamics simulation approaches, we found that both OTUB1 and OTUB2 display a catalytic triad characteristic of proteases but differ in their configuration and protonation states. The OTUB1 protein had a prearranged catalytic site, with strong electrostatic interactions between the active-site residues His265 and Asp267 In OTUB2, however, the arrangement of the catalytic triad was different. In the absence of ubiquitin, the neutral states of the catalytic-site residues in OTUB2 were more stable, resulting in larger distances between these residues. Only upon ubiquitin binding did the catalytic triad in OTUB2 rearrange and bring the active site into a catalytically feasible state. An analysis of water access channels revealed only a few diffusion trajectories for the catalytically active form of OTUB1, whereas in OTUB2 the catalytic site was solvent-accessible, and a larger number of water molecules reached and left the binding pocket. Interestingly, in OTUB2, the catalytic residues His224 and Asn226 formed a stable hydrogen bond. We propose that the observed differences in activation kinetics, protonation states, water channels, and active-site accessibility between OTUB1 and OTUB2 may be relevant for the selective design of OTU inhibitors.


Assuntos
Cisteína Endopeptidases/química , Simulação de Dinâmica Molecular , Tioléster Hidrolases/química , Domínio Catalítico , Enzimas Desubiquitinantes , Ativação Enzimática , Humanos , Ligação de Hidrogênio
18.
Plant Physiol ; 182(4): 1946-1965, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32005783

RESUMO

Xyloglucan is the major hemicellulose of dicotyledon primary cell walls, affecting the load-bearing framework with the participation of xyloglucan endo-transglycosylase/hydrolases (XTHs). We used loss- and gain-of function approaches to study functions of XTH4 and XTH9 abundantly expressed in cambial regions during secondary growth of Arabidopsis (Arabidopsis thaliana). In secondarily thickened hypocotyls, these enzymes had positive effects on vessel element expansion and fiber intrusive growth. They also stimulated secondary wall thickening but reduced secondary xylem production. Cell wall analyses of inflorescence stems revealed changes in lignin, cellulose, and matrix sugar composition indicating an overall increase in secondary versus primary walls in mutants, indicative of higher xylem production compared with the wild type (since secondary walls were thinner). Intriguingly, the number of secondary cell wall layers compared with the wild type was increased in xth9 and reduced in xth4, whereas the double mutant xth4x9 displayed an intermediate number of layers. These changes correlated with specific Raman signals from the walls, indicating changes in lignin and cellulose. Secondary walls were affected also in the interfascicular fibers, where neither XTH4 nor XTH9 was expressed, indicating that these effects were indirect. Transcripts involved in secondary wall biosynthesis and cell wall integrity sensing, including THESEUS1 and WALL ASSOCIATED KINASE2, were highly induced in the mutants, indicating that deficiency in XTH4 and XTH9 triggers cell wall integrity signaling, which, we propose, stimulates xylem cell production and modulates secondary wall thickening. Prominent effects of XTH4 and XTH9 on secondary xylem support the hypothesis that altered xyloglucan affects wood properties both directly and via cell wall integrity sensing.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Parede Celular/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Celulose/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Glucanos/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Xilanos/metabolismo , Xilema/metabolismo
19.
Int J Mol Sci ; 22(16)2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34445195

RESUMO

BACKGROUND: Runt-related transcription factor (RUNX1) regulates inflammation in non-alcoholic steatohepatitis (NASH). METHODS: We performed in vivo targeted silencing of the RUNX1 gene in liver sinusoidal endothelial cells (LSECs) by using vegfr3 antibody tagged immunonano-lipocarriers encapsulated RUNX1 siRNA (RUNX1 siRNA) in murine models of methionine choline deficient (MCD) diet-induced NASH. MCD mice given nanolipocarriers-encapsulated negative siRNA were vehicle, and mice with standard diet were controls. RESULTS: Liver RUNX1 expression was increased in the LSECs of MCD mice in comparison to controls. RUNX1 protein expression was decreased by 40% in CD31-positive LSECs of RUNX1 siRNA mice in comparison to vehicle, resulting in the downregulation of adhesion molecules, ICAM1 expression, and VCAM1 expression in LSECs. There was a marked decrease in infiltrated T cells and myeloid cells along with reduced inflammatory cytokines in the liver of RUNX1 siRNA mice as compared to that observed in the vehicle. CONCLUSIONS: In vivo LSEC-specific silencing of RUNX1 using immunonano-lipocarriers encapsulated siRNA effectively reduces its expression of adhesion molecules, infiltrate on of immune cells in liver, and inflammation in NASH.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/genética , Inflamação/genética , Hepatopatia Gordurosa não Alcoólica/genética , Interferência de RNA , RNA Interferente Pequeno/genética , Animais , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Inflamação/terapia , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/terapia , RNA Interferente Pequeno/uso terapêutico , Terapêutica com RNAi
20.
Trop Anim Health Prod ; 53(2): 278, 2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33886008

RESUMO

Privately practicing paravets have been under value assessment since a long time vis-à-vis delivery of prompt and efficient animal husbandry services at farmer's doorstep. Wide variation in educational qualifications, training duration, and the shortage of veterinarians could act as impetus to test suitability of service provider to availability, accessibility, acceptability, adequacy, and affordability by farmers. The present study was conceptualized to analyze the role perception by delineating role priorities and to assess the role performance of paravets in perspective of stakeholders, namely trainers of paravet schools and paravets themselves. In the study, analytical hierarchical process (AHP) has been used to establish role priority for para-veterinary services. Two indices, namely, role performance index (RPI) and perceived effective index of measures (PEIM), were devised to assess the prospects of effective delivery of minor veterinary services. Results indicated that paravets perceived roles under productive services as first priority, followed by preventive services, curative services, while miscellaneous services as last priority (0.237), while trainers perceived preventive services as the first priority. Results of chi-square test revealed that variables such as age, experience, and educational qualification of trainers were found significant and had a positive association with the scores of evaluative role performance of minor veterinary services and perceived effectiveness of measures to improve para-veterinary services.


Assuntos
Fazendeiros , Médicos Veterinários , Criação de Animais Domésticos , Animais , Serviços de Saúde , Humanos , Índia , Percepção
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