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1.
Mol Microbiol ; 122(4): 549-562, 2024 10.
Artigo em Inglês | MEDLINE | ID: mdl-39275982

RESUMO

In E. coli K-12, the absence of unphosphorylated PtsN (unphospho-PtsN) has been proposed to cause an L-leucine-sensitive growth phenotype (LeuS) by hyperactivated K+ uptake mediated impairment of the expression of the ilvBN operon, encoding subunits of the L-valine (Val)-sensitive acetohydroxyacid synthase I (AHAS I) that renders residual AHAS activity susceptible to inhibition by Leu and K+. This leads to AHAS insufficiency and a requirement for L-isoleucine (Ile). Herein, we provide an alternate mechanism for the LeuS of the ∆ptsN mutant. Genetic and physiological studies with suppressors of the LeuS indicate that impaired expression of the ilvBN operon jointly caused by the absence of unphospho-PtsN and the presence of Leu coupled to Leu-mediated repression of expression of AHAS III leads to AHAS insufficiency rendering residual AHAS activity susceptible to chronic Val stress that may be generated by exogenous Leu. Hyperactivated K+ uptake and an elevated α-ketobutyrate level mediate elevation of ilvBN expression and alleviate the LeuS. The requirement of unphospho-PtsN as a positive regulator of ilvBN expression may buffer Ile biosynthesis against Leu-mediated AHAS insufficiency and protect AHAS I function from chronic endogenous Val generated by Leu and could be realized in certain environments that impair AHAS function.


Assuntos
Acetolactato Sintase , Proteínas de Escherichia coli , Regulação Bacteriana da Expressão Gênica , Leucina , Óperon , Leucina/metabolismo , Leucina/farmacologia , Acetolactato Sintase/metabolismo , Acetolactato Sintase/genética , Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Sistema Fosfotransferase de Açúcar do Fosfoenolpiruvato/metabolismo , Sistema Fosfotransferase de Açúcar do Fosfoenolpiruvato/genética , Isoleucina/metabolismo , Valina/metabolismo , Potássio/metabolismo , Fosforilação , Escherichia coli K12/genética , Escherichia coli K12/metabolismo , Escherichia coli K12/crescimento & desenvolvimento , Escherichia coli K12/efeitos dos fármacos , Mutação
2.
Exp Cell Res ; 441(2): 114171, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39029573

RESUMO

Stromal-epithelial communication is an absolute necessity when it comes to the morphogenesis and pathogenesis of solid tissues, including the prostate and breast. So far, signalling pathways of several growth factors have been investigated. Besides such chemical factors, non-coding RNAs such as miRNAs have recently gained much interest because of their variety and complexity of action. Prostate and breast tissues being highly responsive to steroid hormones such as androgen and estrogen, respectively, it is not surprising that a huge set of available literature critically investigated the interplay between such hormones and miRNAs, especially in carcinogenesis. This review showcases our effort to highlight hormonally-related miRNAs that also somehow perturb the regular stromal-epithelial interactions during carcinogenesis in the prostate and breast. In future, we look forward to exploring how hormonal changes in the tissue microenvironment bring about miRNA-mediated changes in stromal-epithelial interactome in carcinogenesis and cancer progression.


Assuntos
Neoplasias da Mama , MicroRNAs , Neoplasias da Próstata , Células Estromais , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Neoplasias da Próstata/metabolismo , Masculino , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Células Estromais/metabolismo , Células Estromais/patologia , Feminino , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Comunicação Celular/genética , Animais , Microambiente Tumoral/genética , Regulação Neoplásica da Expressão Gênica
3.
Med Res Rev ; 44(3): 939-974, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38129992

RESUMO

Virtual screening (VS) is an integral and ever-evolving domain of drug discovery framework. The VS is traditionally classified into ligand-based (LB) and structure-based (SB) approaches. Machine intelligence or artificial intelligence has wide applications in the drug discovery domain to reduce time and resource consumption. In combination with machine intelligence algorithms, VS has emerged into revolutionarily progressive technology that learns within robust decision orders for data curation and hit molecule screening from large VS libraries in minutes or hours. The exponential growth of chemical and biological data has evolved as "big-data" in the public domain demands modern and advanced machine intelligence-driven VS approaches to screen hit molecules from ultra-large VS libraries. VS has evolved from an individual approach (LB and SB) to integrated LB and SB techniques to explore various ligand and target protein aspects for the enhanced rate of appropriate hit molecule prediction. Current trends demand advanced and intelligent solutions to handle enormous data in drug discovery domain for screening and optimizing hits or lead with fewer or no false positive hits. Following the big-data drift and tremendous growth in computational architecture, we presented this review. Here, the article categorized and emphasized individual VS techniques, detailed literature presented for machine learning implementation, modern machine intelligence approaches, and limitations and deliberated the future prospects.


Assuntos
Inteligência Artificial , Descoberta de Drogas , Humanos , Ligantes , Descoberta de Drogas/métodos , Algoritmos
4.
Appl Environ Microbiol ; 90(10): e0102624, 2024 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-39248464

RESUMO

Interactions between plants and soil microbial communities that benefit plant growth and enhance nutrient acquisition are driven by the selective release of metabolites from plant roots, or root exudation. To investigate these plant-microbe interactions, we developed a photoaffinity probe based on sorgoleone (sorgoleone diazirine alkyne for photoaffinity labeling, SoDA-PAL), a hydrophobic secondary metabolite and allelochemical produced in Sorghum bicolor root exudates. We applied SoDA-PAL to the identification of sorgoleone-binding proteins in Acinetobacter pittii SO1, a potential plant growth-promoting microbe isolated from sorghum rhizosphere soil. Competitive photoaffinity labeling of A. pittii whole cell lysates with SoDA-PAL identified 137 statistically enriched proteins, including putative transporters, transcriptional regulators, and a subset of proteins with predicted enzymatic functions. We performed computational protein modeling and docking with sorgoleone to prioritize candidates for experimental validation and then confirmed binding of sorgoleone to four of these proteins in vitro: the α/ß fold hydrolase SrgB (OH685_09420), a fumarylacetoacetase (OH685_02300), a lysophospholipase (OH685_14215), and an unannotated hypothetical protein (OH685_18625). Our application of this specialized sorgoleone-based probe coupled with structural bioinformatics streamlines the identification of microbial proteins involved in metabolite recognition, metabolism, and toxicity, widening our understanding of the range of cellular pathways that can be affected by a plant secondary metabolite.IMPORTANCEHere, we demonstrate that a photoaffinity-based chemical probe modeled after sorgoleone, an important secondary metabolite released by sorghum roots, can be used to identify microbial proteins that directly interact with sorgoleone. We applied this probe to the sorghum-associated bacterium Acinetobacter pittii and showed that probe labeling is dose-dependent and sensitive to competition with purified sorgoleone. Coupling the probe with proteomics and computational analysis facilitated the identification of putative sorgoleone binders, including a protein implicated in a conserved pathway essential for sorgoleone catabolism. We anticipate that discoveries seeded by this workflow will expand our understanding of the molecular mechanisms by which specific metabolites in root exudates shape the sorghum rhizosphere microbiome.


Assuntos
Acinetobacter , Sorghum , Acinetobacter/metabolismo , Acinetobacter/genética , Sorghum/microbiologia , Sorghum/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Marcadores de Fotoafinidade/metabolismo , Microbiologia do Solo , Raízes de Plantas/microbiologia , Rizosfera , Lipídeos , Benzoquinonas
5.
Fish Shellfish Immunol ; 154: 109949, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39389172

RESUMO

The present study addresses the challenges of uncontrolled temperature and pollution in aquatic environments, with a focus on fish ability to tolerate high temperature. The investigation aimed to determine the role of iron nanoparticles (Fe-NPs) in enhancing the thermal tolerance of Pangasianodon hypophthalmus exposed to high-temperature stress, arsenic (As), and ammonia (NH3) toxicity. Fe-NPs were synthesized using green approaches, specifically from fish gill. The dietary Fe-NPs were formulated and supplemented at 10, 15, and 20 mg kg⁻1 of feed. Notably, Fe-NPs at 15 mg kg⁻1 diet significantly reduced the critical thermal minimum (CTmin) (14.44 ± 0.21 °C) and the lethal thermal minimum (LTmin) (13.46 ± 0.15 °C), compared to the control and other treatment groups. Conversely, when Fe-NPs at 15 mg kg⁻1 were supplemented with or without exposure to stressors (As + NH3+T), the critical thermal maximum (CTmax) increased to 47.59 ± 0.16 °C, and the lethal thermal maximum (LTmax) increased to 48.60 ± 0.37 °C, both significantly higher than the control and other groups. A strong correlation was observed between LTmin and CTmin (R2 = 0.90) and between CTmax and LTmax (R2 = 0.98). Furthermore, dietary Fe-NPs at 15 mg kg⁻1 significantly upregulated the expression of stress-related genes, including HSP70, iNOS, Caspase-3a, CYP450, MT, cat, sod, gpx, TNFα, IL, TLR, and Ig. The enhanced thermal tolerance (LTmin and LTmax) can be attributed to these gene regulations, suggesting the mechanistic involvement of Fe-NPs in improving thermal resilience. Overall, the findings demonstrate that dietary supplementation with Fe-NPs, particularly at 15 mg kg⁻1, improves thermal tolerance and stress response in P. hypophthalmus by enhancing gene expression and overall thermal efficiency under stressor conditions.

6.
CNS Spectr ; 29(2): 87-95, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38282559

RESUMO

Data related to psychiatric manifestations in subacute sclerosing panencephalitis (SSPE) is currently available only in the form of isolated case reports. In this systematic review, we evaluated the spectrum of psychiatric manifestations and their impact on the course and outcome of SSPE. Data were obtained from 4 databases (PubMed, Embase, Scopus, and Google Scholar), with the most recent search conducted on March 27, 2023. The PRISMA guidelines were followed, and the PROSPERO registration number for the protocol is CRD42023408227. SSPE was diagnosed using Dyken's criteria. Extracted data were recorded in an Excel spreadsheet. To evaluate the quality of the data, the Joanna Briggs Institute Critical Appraisal tool was employed. Our search resulted in 30 published reports of 32 patients. The mean age was 17.9 years. Schizophrenia, catatonia, and poorly characterized psychotic illnesses were the 3 most common psychiatric presentations that were seen in 63% (20/32) of cases. Catatonia was seen in 4 patients. Affective disorders, mania, and depression were reported among 22% (7/32) cases. In approximately 81% (26/32) cases, the course of SSPE was acute fulminant. Treatment with antipsychotic drugs had poor or no response. Out of 17 patients, who received antipsychotic drugs, 6 patients noted severe extrapyramidal adverse effects. SSPE often masquerades as a psychiatric disorder. Unresponsive psychiatric symptoms, early extrapyramidal signs, and progressive encephalopathy indicate SSPE.


Assuntos
Panencefalite Esclerosante Subaguda , Panencefalite Esclerosante Subaguda/complicações , Humanos , Catatonia/etiologia , Catatonia/diagnóstico , Adolescente , Esquizofrenia
7.
Neurol Sci ; 45(7): 3069-3091, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38512528

RESUMO

Measles inclusion-body encephalitis (MIBE) is rare, with insights largely from case studies. We systematically analyzed subacute Sclerosing Panencephalitis (SSPE) cases in immunocompromised patients, identifying distinctive clinical and neuroimaging features. These findings could facilitate MIBE diagnosis without the need for brain biopsies. Our systematic review on MIBE and HIV-related SSPE adhered to PRISMA guidelines and was registered with PROSPERO. We searched multiple databases and followed a detailed inclusion process with independent reviews and quality assessment. Data on patient demographics, clinical features, and outcomes were compiled. A review of 39 studies on 49 MIBE patients and 8 reports on HIV-positive SSPE patients was conducted. Acute lymphoblastic leukemia, HIV, organ transplants, and malignancies were common precursors to MIBE. Perinatal HIV was prevalent among SSPE cases. Seizures were the primary symptom in MIBE, often drug-resistant and progressing to status epilepticus or epilepsia partialis continua, whereas periodic myoclonus was universal in SSPE. Neuroimaging showed distinct patterns for each group, and histopathology confirmed measles virus presence in 39% of MIBE cases. MIBE patients typically progressed to coma and death. In conclusion, MIBE and SSPE in HIV-infected patients present with distinct clinical pictures but identical brain pathological abnormalities.


Assuntos
Sarampo , Neuroimagem , Panencefalite Esclerosante Subaguda , Humanos , Panencefalite Esclerosante Subaguda/diagnóstico por imagem , Panencefalite Esclerosante Subaguda/patologia , Panencefalite Esclerosante Subaguda/complicações , Neuroimagem/métodos , Sarampo/complicações , Sarampo/patologia , Sarampo/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Encéfalo/patologia
8.
Neurosurg Rev ; 47(1): 278, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38884687

RESUMO

This letter provides a critical assessment of a previous study on the utility of whole tumor apparent diffusion coefficient (ADC) histogram characteristics in predicting meningioma progesterone receptor expression. While acknowledging the benefits of employing classical diffusion-weighted imaging (DWI) for non-invasive tumor evaluation, it also emphasizes significant drawbacks. Advanced imaging techniques such as diffusion tensor imaging (DTI) and diffusion kurtosis imaging (DKI) were not used in the study, which could have provided a more comprehensive understanding of tumor microstructure and heterogeneity. Furthermore, the inclusion of necrotic and cystic areas in ADC analysis may distort results due to their different diffusion properties. While focusing on first-order ADC histogram characteristics is useful, it ignores the potential insights gained from higher-order features and texture analysis. These limitations indicate that future research should combine improved imaging modalities with thorough analytical methodologies to increase the predictive value of imaging biomarkers for meningioma features and progesterone receptor expression.


Assuntos
Imagem de Difusão por Ressonância Magnética , Neoplasias Meníngeas , Meningioma , Receptores de Progesterona , Meningioma/diagnóstico por imagem , Meningioma/patologia , Meningioma/metabolismo , Humanos , Receptores de Progesterona/metabolismo , Neoplasias Meníngeas/diagnóstico por imagem , Neoplasias Meníngeas/patologia , Neoplasias Meníngeas/metabolismo , Imagem de Difusão por Ressonância Magnética/métodos , Feminino
9.
Chem Biodivers ; : e202401981, 2024 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-39429127

RESUMO

Globally, cancer is one of the leading causes of death. Resistance to conventional medications, such as chemotherapy and radiation, continues to be a significant challenge in the treatment of cancer despite the availability of numerous medicines. Therefore, the highest priority is to hunt for new therapeutic agents. Transforming growth factor-beta is a pivotal regulatory cytokine that exerts significant influence over cellular processes, particularly emphasizing its role in facilitating and modulating cell proliferation. TGFß1, identified as most promising active site of the TGF-ß signaling, is a potent drug target site that has garnered wide attention for developing new anticancer agents. The present investigation investigates the potential phytochemicals as TGFßR1 inhibitors. The SB431542 complexed TGFßR1 protein model was used to screen the natural product database to obtain a compound with high binding potential. NPC247629 has emerged as the best-scored compound among all the screened compounds, demonstrating the highest affinity towards the TGFßR1 regarding docking score -17.54 kcal/mol. The MD simulation study indicated that all proposed hits are retained inside the receptor in dynamic states. The best-screened hits, NPC247629 and NPC60735, have excellent binding affinity and hold a massive potential for TGFßR1 inhibition, paving the way for promising future investigations in cancer treatment.

10.
Ann Plast Surg ; 92(4S Suppl 2): S279-S283, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38556690

RESUMO

BACKGROUND: Burns constitute a major global health challenge, causing over 11 million injuries and 300,000 deaths annually and surpassing the economic burden of cervical cancer and HIV combined. Despite this, patient-level financial consequences of burn injuries remain poorly quantified, with a significant gap in data from low- and middle-income countries. In this study, we evaluate financial toxicity in burn patients. METHODS: A prospective, multicenter cohort study was conducted across two tertiary care hospitals in India, assessing 123 adult surgical in-patients undergoing operative interventions for burn injuries. Patient sociodemographic, clinical, and financial data were collected through surveys and electronic records during hospitalization and at 1, 3, and 6 months postoperatively. Out-of-pocket costs (OOPCs) for surgical burn treatment were evaluated during hospitalization. Longitudinal changes in income, employment status, and affordability of basic subsistence needs were assessed at the 1-, 3-, and 6-month postoperative time point. Degree of financial toxicity was calculated using a combination of the metrics catastrophic health expenditure and financial hardship. Development of financial toxicity was compared by sociodemographic and clinical characteristics using logistic regression models. RESULTS: Of the cohort, 60% experienced financial toxicity. Median OOPCs was US$555.32 with the majority of OOPCs stemming from direct nonmedical costs (US$318.45). Cost of initial hospitalization exceeded monthly annual income by 80%. Following surgical burn care, income decreased by US$318.18 within 6 months, accompanied by a 53% increase in unemployment rates. At least 40% of the cohort consistently reported inability to afford basic subsistence needs within the 6-month perioperative period. Significant predictors of developing financial toxicity included male gender (odds ratio, 4.17; 95% confidence interval, 1.25-14.29; P = 0.02) and hospital stays exceeding 20 days (odds ratio, 11.17; 95% confidence interval, 2.11-59.22; P ≤ 0.01). CONCLUSIONS: Surgical treatment for burn injuries is associated with substantial financial toxicity. National and local policies must expand their scope beyond direct medical costs to address direct nonmedical and indirect costs. These include burn care insurance, teleconsultation follow-ups, hospital-affiliated subsidized lodging, and resources for occupational support and rehabilitation. These measures are crucial to alleviate the financial burden of burn care, particularly during the perioperative period.


Assuntos
Queimaduras , Estresse Financeiro , Adulto , Humanos , Masculino , Queimaduras/epidemiologia , Queimaduras/cirurgia , Estudos de Coortes , Efeitos Psicossociais da Doença , Complicações Intraoperatórias , Estudos Prospectivos , Feminino
11.
Environ Toxicol ; 39(3): 1581-1600, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38009665

RESUMO

The current study focused on assessing the toxicological effects of copper (Cu) and copper nanoparticles (Cu-NPs) in acute condition on Pangasianodon hypophthalmus. The median lethal concentration (LC50 ) for Cu and Cu-NPs were determined as 8.04 and 3.85 mg L-1 , respectively. For the subsequent definitive test, varying concentrations were selected: 7.0, 7.5, 8.0, 8.5, and 9.0 mg L-1 for Cu, and 3.0, 3.3, 3.6, 3.9, and 4.2 mg L-1 for Cu-NPs. To encompass these concentration levels and assess their toxic effects, biomarkers associated with toxicological studies like oxidative stress, neurotransmission, and cellular metabolism were measured in the liver, kidney, and gill tissues. Notably, during the acute test, the activities of catalase, superoxide dismutase, glutathione-s-transferase, glutathione peroxidase, and lipid peroxide in the liver, gill, and kidney tissues were significantly increased due to exposure to Cu and Cu-NPs. Similarly, acetylcholinesterase activity in the brain was notably inhibited in the presence of Cu and Cu-NPs when compared to the control group. Cellular metabolic stress was greatly influenced by the exposure to Cu and Cu-NPs, evident from the considerable elevation of cortisol, HSP 70, and blood glucose levels in the treated groups. Furthermore, integrated biomarker response, genotoxicity, DNA damage in gill tissue, karyotyping in kidney tissue, and histopathology in gill and liver were investigated, revealing tissue damage attributed to exposure to Cu and Cu-NPs. In conclusion, this study determined that elevated concentrations of essential trace elements, namely Cu and Cu-NPs, induce toxicity and disrupt cellular metabolic activities in fish.


Assuntos
Peixes-Gato , Poluentes Químicos da Água , Animais , Cobre/toxicidade , Acetilcolinesterase/metabolismo , Estresse Oxidativo , Catalase/metabolismo , Biomarcadores/metabolismo , Brânquias/metabolismo , Poluentes Químicos da Água/toxicidade
12.
Mycopathologia ; 189(4): 54, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38865003

RESUMO

BACKGROUND: During the COVID-19 pandemic-associated mucor epidemic, acute antifungal drug shortage necessitated the exploration of other antifungals based on culture sensitivity. Itraconazole is a cheap, safe, and effective antifungal in sensitive cases. METHODOLOGY: We enrolled itraconazole-sensitive COVID-19-associated mucormycosis during the mucormycosis pandemic. After the intensive phase course of liposomal amphotericin B, Itraconazole was offered in susceptible cases during the maintenance phase along with standard of care. These patients were clinically and radiologically followed for 6 months. RESULTS: We enrolled 14 patients (Male: Female-11:3) of Rhino-orbito-cerebral mucormycosis (ROCM) which included 12 diabetics. All patients had facial swelling, orbital swelling, visual impairment, and headache. MRI showed involvement of bilateral sinus (10/14), orbital extension (13/14), cavernous sinus (5/14), cerebral part of the internal carotid artery (3/14), and brain infarcts (4/14). All 14 patients showed sensitivity to Itraconazole with 12 having minimum inhibitory concentration (MIC) ≤ 1 µg/ml and 2 having MIC ≤ 2 µg/ml. Follow-up at 6 months showed clinical improvement in the majority (11/14) and radiological improvement in six out of seven scanned patients. CONCLUSION: Our study shows the potential therapeutic role of oral Itraconazole in ROCM.


Assuntos
Anfotericina B , Antifúngicos , Itraconazol , Mucormicose , Rhizopus oryzae , Humanos , Masculino , Itraconazol/uso terapêutico , Itraconazol/administração & dosagem , Feminino , Mucormicose/tratamento farmacológico , Anfotericina B/uso terapêutico , Anfotericina B/administração & dosagem , Antifúngicos/uso terapêutico , Antifúngicos/administração & dosagem , Pessoa de Meia-Idade , Adulto , Rhizopus oryzae/efeitos dos fármacos , Testes de Sensibilidade Microbiana , COVID-19/complicações , Idoso , Quimioterapia Combinada , Resultado do Tratamento
13.
Chem Soc Rev ; 52(15): 5135-5171, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37458261

RESUMO

Cytochrome P450s (Cyt P450s) and peroxidases are enzymes featuring iron heme cofactors that have wide applicability as biocatalysts in chemical syntheses. Cyt P450s are a family of monooxygenases that oxidize fatty acids, steroids, and xenobiotics, synthesize hormones, and convert drugs and other chemicals to metabolites. Peroxidases are involved in breaking down hydrogen peroxide and can oxidize organic compounds during this process. Both heme-containing enzymes utilize active FeIVO intermediates to oxidize reactants. By incorporating these enzymes in stable thin films on electrodes, Cyt P450s and peroxidases can accept electrons from an electrode, albeit by different mechanisms, and catalyze organic transformations in a feasible and cost-effective way. This is an advantageous approach, often called bioelectrocatalysis, compared to their biological pathways in solution that require expensive biochemical reductants such as NADPH or additional enzymes to recycle NADPH for Cyt P450s. Bioelectrocatalysis also serves as an ex situ platform to investigate metabolism of drugs and bio-relevant chemicals. In this paper we review biocatalytic electrochemical reactions using Cyt P450s including C-H activation, S-oxidation, epoxidation, N-hydroxylation, and oxidative N-, and O-dealkylation; as well as reactions catalyzed by peroxidases including synthetically important oxidations of organic compounds. Design aspects of these bioelectrocatalytic reactions are presented and discussed, including enzyme film formation on electrodes, temperature, pH, solvents, and activation of the enzymes. Finally, we discuss challenges and future perspective of these two important bioelectrocatalytic systems.

14.
Molecules ; 29(11)2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38893400

RESUMO

The outbreak of SARS-CoV-2, also known as the COVID-19 pandemic, is still a critical risk factor for both human life and the global economy. Although, several promising therapies have been introduced in the literature to inhibit SARS-CoV-2, most of them are synthetic drugs that may have some adverse effects on the human body. Therefore, the main objective of this study was to carry out an in-silico investigation into the medicinal properties of Petiveria alliacea L. (P. alliacea L.)-mediated phytocompounds for the treatment of SARS-CoV-2 infections since phytochemicals have fewer adverse effects compared to synthetic drugs. To explore potential phytocompounds from P. alliacea L. as candidate drug molecules, we selected the infection-causing main protease (Mpro) of SARS-CoV-2 as the receptor protein. The molecular docking analysis of these receptor proteins with the different phytocompounds of P. alliacea L. was performed using AutoDock Vina. Then, we selected the three top-ranked phytocompounds (myricitrin, engeletin, and astilbin) as the candidate drug molecules based on their highest binding affinity scores of -8.9, -8.7 and -8.3 (Kcal/mol), respectively. Then, a 100 ns molecular dynamics (MD) simulation study was performed for their complexes with Mpro using YASARA software, computed RMSD, RMSF, PCA, DCCM, MM/PBSA, and free energy landscape (FEL), and found their almost stable binding performance. In addition, biological activity, ADME/T, DFT, and drug-likeness analyses exhibited the suitable pharmacokinetics properties of the selected phytocompounds. Therefore, the results of this study might be a useful resource for formulating a safe treatment plan for SARS-CoV-2 infections after experimental validation in wet-lab and clinical trials.


Assuntos
Antivirais , Tratamento Farmacológico da COVID-19 , Proteases 3C de Coronavírus , Compostos Fitoquímicos , SARS-CoV-2 , Humanos , Antivirais/farmacologia , Antivirais/química , Antivirais/uso terapêutico , Proteases 3C de Coronavírus/antagonistas & inibidores , Proteases 3C de Coronavírus/metabolismo , Proteases 3C de Coronavírus/química , COVID-19/virologia , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/química , Compostos Fitoquímicos/uso terapêutico , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Inibidores de Proteases/farmacologia , Inibidores de Proteases/química , Inibidores de Proteases/uso terapêutico , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/enzimologia
15.
Fish Physiol Biochem ; 50(1): 239-258, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37656302

RESUMO

Pollution and climate change pose significant threats to aquatic ecosystems, with adverse impacts on aquatic animals, including fish. Climate change increases the toxicity of metal in aquatic ecosystems. To understand the severity of metal pollution and climate change, an experiment was conducted to delineate the mitigation potential of selenium (Se) and selenium nanoparticles (Se-NPs) against lead (Pb) and high temperature stress in Pangasianodon hypophthalmus. For the experiment, five isonitrogenous and isocaloric diets were prepared, varying in selenium supplementation as Se at 0, 1, and 2 mg kg-1 diet, and Se-NPs at 1 and 2 mg kg-1 diet. The fish in stressor groups were exposed to Pb (1/20th of LC50 concentration, 4 ppm) and high temperature (34 °C) throughout the experiment. The results demonstrated that dietary supplementation of Se at 1 and 2 mg kg-1 diet, as well as Se-NPs at 1 mg kg-1 diet, significantly reduced (p < 0.01) the levels of lactate dehydrogenase and malate dehydrogenase in both liver and muscle tissues. Additionally, the levels of alanine aminotransferase and aspartate aminotransferase in both gill and liver tissues were significantly decreased (p < 0.01) with the inclusion of Se and Se-NPs in the diets. Furthermore, the enzymes glucose-6-phosphate dehydrogenase in gill and liver tissues, fructose 1,6-bisphosphatase in liver and muscle tissues, and acid phosphatase in liver tissue were remarkably reduced (p < 0.01) due to the supplementation of Se and Se-NPs. Moreover, dietary supplementation of Se and Se-NPs significantly enhanced (p < 0.01) the activity of pyruvate kinase, glucokinase, hexokinase, alkaline phosphatase, ATPase, protease, amylase, lipase, and RNA/DNA ratio in the fish. Histopathological examination of gill and liver tissues also indicated that Se and Se-NPs protected against structural damage caused by lead and high-temperature stress. Moreover, the study examined the bioaccumulation of selenium and lead in muscle, water, and diets. The aim of the study revealed that Se and Se-NPs effectively protected the fish from lead toxicity and high-temperature stress, while also improving the function of cellular metabolic enzymes in P. hypophthalmus.


Assuntos
Peixes-Gato , Nanopartículas , Selênio , Animais , Chumbo/metabolismo , Ecossistema , Antioxidantes/metabolismo , Peixes-Gato/fisiologia
16.
Environ Geochem Health ; 46(8): 298, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38980518

RESUMO

Grass carp intestinal waste-mediated biosynthesized nanosilver (AgNPs) was valorized using guaran and zeolite matrices, resulting in AgNPs-guaran, AgNPs-zeolite, and AgNPs-guaran -zeolite composites. The valorized products were examined using Environmental Scanning Electron Microscopy, Energy Dispersive X-ray analysis and X-ray Diffraction analysis to confirm uniform dispersion and entrapment of AgNPs within the matrixes. These valorized products were evaluated for their efficacy in detoxifying the ubiquitous and toxic hexavalent chromium (Cr6+) in aquatic environments, with Anabas testudineus exposed to 2 mg l-1 of Cr6+ for 60 days. Remarkable reduction of Cr6+ concentration to 0.86 ± 0.007 mg l-1 was achieved with AgNPs-guaran-zeolite composite, indicating successful reclamation of contaminated water and food safety assurance. Consistency in results was further corroborated by minimal stress-related alterations in fish physiological parameters and integrated biomarker response within the experimental group treated with the AgNPs-guaran-zeolite composite. Despite observed chromium accumulation in fish tissues, evidence of physiological stability was apparent, potentially attributable to trivalent chromium accumulation, serving as an essential nutrient for the fish. Additionally, the challenge study involving Anabas testudineus exposed to Aeromonas hydrophila exhibited the lowest cumulative mortality (11.11%) and highest survival rate (87.5%) within the same experimental group. The current study presents a novel approach encompassing the valorization of AgNPs for Cr6+ detoxification under neutral to alkaline pH conditions, offering a comprehensive framework for environmental remediation.


Assuntos
Biomarcadores , Cromo , Nanopartículas Metálicas , Prata , Poluentes Químicos da Água , Zeolitas , Animais , Cromo/química , Zeolitas/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade , Prata/química , Prata/toxicidade , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Hidrogéis/química , Bioacumulação , Inativação Metabólica , Galactanos , Mananas , Gomas Vegetais
17.
Indian Pacing Electrophysiol J ; 24(1): 49-52, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38110029

RESUMO

BACKGROUND: Anomalous left brachiocephalic vein (ALBCV) is a rare venous anomaly. Double Left brachiocephalic vein is the rarest type of ALBCV anomaly. CASE REPORT: Here we report a case of gentleman with post myocardial infarction ventricular tachycardia who underwent ICD implantation, where we could not place the lead initially through left side. CT angiography revealed presence of a duplicated circumaortic left BCV. It's cranial limb coursing normally anterior to arch and compressed at its confluence with RBCV and the caudal limb with a subaortic course draining into the RSVC. We report this first case of double LBCV along with right sided aortic arch and aberrant origin of LSCA arising from Kommerel's diverticulum. CONCLUSION: This case highlights that interventional cardiologists should be aware of these venous anomalies for proper planning and implantation of CIED successfully via transvenous approach.

18.
J Neurophysiol ; 129(1): 199-210, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36541609

RESUMO

Brain dynamics recorded via electroencephalography (EEG) is conceptualized as a sum of two components: "phase-locked" and "non-phase-locked" to the stimulus. Phase-locked activity is often implicitly studied as event-related potentials (ERPs), and the trial-averaged estimates-evoked potentials (EP) considered both time-locked and phase-locked to the stimulus. The non-phase-locked activity, on the other hand, refers to an increase in power in a narrow band or broadband frequencies in the signal emerging at variable phases from stimulus initiation. Both components are understood to stem from different neuronal mechanisms; hence, accurately characterizing them is of immense importance to neuroscientific studies. Here, we discuss the drawbacks of currently used methods to separate the phase-locked and non-phase-locked activity and propose a novel concurrent phaser method (CPM) that simultaneously decomposes the two components. First, we establish that the single-trial separation of phase-locked and non-phase-locked power is an ill-posed problem. Second, using simulations where ground truth validation is possible, we elucidate how the estimation of non-phase-locked power gets biased by phase-locked power in the state-of-the-art averaging method and ways to resolve the issue using CPM. Next, we use two experimental EEG datasets-audio oddball and auditory steady-state responses (ASSR) to show that empirical signal-to-noise estimates warrant the usage of CPM to separate phase-locked and non-phase-locked activity. Thus, using ground truth validation from simulations and demonstration in real experimental scenarios, the efficacy of the proposed CPM is established.NEW & NOTEWORTHY Parametric models for estimation of phase-locked and non-phase-locked brain signals reveals how estimation of non-phase-locked component is biased by the variability of phase-locked component and at the level of single trial becomes an ill-posed problem. Furthermore, the modeling framework delimits the boundaries where traditional averaging approach can be trusted to estimate the phase-locked and non-phase-locked components.


Assuntos
Eletroencefalografia , Potenciais Evocados , Eletroencefalografia/métodos , Potenciais Evocados/fisiologia , Encéfalo/fisiologia , Tempo de Reação/fisiologia , Cognição
19.
Breast Cancer Res Treat ; 200(2): 225-235, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37209182

RESUMO

PURPOSE: PAM50 profiling assigns each breast cancer to a single intrinsic subtype based on a bulk tissue sample. However, individual cancers may show evidence of admixture with an alternate subtype that could affect prognosis and treatment response. We developed a method to model subtype admixture using whole transcriptome data and associated it with tumor, molecular, and survival characteristics for Luminal A (LumA) samples. METHODS: We combined TCGA and METABRIC cohorts and obtained transcriptome, molecular, and clinical data, which yielded 11,379 gene transcripts in common and 1,178 cases assigned to LumA. We used semi-supervised non-negative matrix factorization (ssNMF) to compute the subtype admixture proportions of the four major subtypes-pLumA, pLumB, pHER2, and pBasal-for each case and measured associations with tumor characteristics, molecular features, and survival. RESULTS: Luminal A cases in the lowest versus highest quartile for pLumA transcriptomic proportion had a 27% higher prevalence of stage > 1, nearly a threefold higher prevalence of TP53 mutation, and a hazard ratio of 2.08 for overall mortality. We found positive associations between pHER2 and HER2 positivity by IHC or FISH; between pLumB and PR negativity; and between pBasal and younger age, node positivity, TP53 mutation, and EGFR expression. Predominant basal admixture, in contrast to predominant LumB or HER2 admixture, was not associated with shorter survival. CONCLUSION: Bulk sampling for genomic analyses provides an opportunity to expose intratumor heterogeneity, as reflected by subtype admixture. Our results elucidate the striking extent of diversity among LumA cancers and suggest that determining the extent and type of admixture holds promise for refining individualized therapy. LumA cancers with a high degree of basal admixture appear to have distinct biological characteristics that warrant further study.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/patologia , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Prognóstico , Perfilação da Expressão Gênica
20.
Nat Mater ; 21(4): 423-429, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35190656

RESUMO

Charge neutrality and their expected itinerant nature makes excitons potential transmitters of information. However, exciton mobility remains inaccessible to traditional optical experiments that only create and detect excitons with negligible momentum. Here, using angle-resolved photoemission spectroscopy, we detect dispersing excitons in the quasi-one-dimensional metallic trichalcogenide, TaSe3. The low density of conduction electrons and the low dimensionality in TaSe3 combined with a polaronic renormalization of the conduction band and the poorly screened interaction between these polarons and photo-induced valence holes leads to various excitonic bound states that we interpret as intrachain and interchain excitons, and possibly trions. The thresholds for the formation of a photo-hole together with an exciton appear as side valence bands with dispersions nearly parallel to the main valence band, but shifted to lower excitation energies. The energy separation between side and main valence bands can be controlled by surface doping, enabling the tuning of certain exciton properties.


Assuntos
Elétrons
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