Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Pol J Microbiol ; 73(2): 207-215, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38905281

RESUMO

Chikungunya virus (CHIKV) causes a debilitating fever and joint pain, with no specific antiviral treatment available. Halogenated secondary metabolites from plants are a promising new class of drug candidates against chikungunya, with unique properties that make them effective against the virus. Plants produce these compounds to defend themselves against pests and pathogens, and they are effective against a wide range of viruses, including chikungunya. This study investigated the interactions of halogenated secondary metabolites with nsP2pro, a therapeutic target for CHIKV. A library of sixty-six halogenated plant metabolites screened previously for ADME properties was used. Metabolites without violation of Lipinski's rule were docked with nsP2pro using AutoDock Vina. To find the stability of the pipoxide chlorohydrin-nsP2pro complex, the GROMACS suite was used for MD simulation. The binding free energy of the ligand-protein complex was computed using MMPBSA. Molecular docking studies revealed that halogenated metabolites interact with nsP2pro, suggesting they are possible inhibitors. Pipoxide chlorohydrin showed the greatest affinity to the target. This was further confirmed by the MD simulations, surface accessible area, and MMPBSA studies. Pipoxide chlorohydrin, a halogenated metabolite, was the most potent against nsP2pro in the survey.


Assuntos
Antivirais , Vírus Chikungunya , Simulação de Acoplamento Molecular , Vírus Chikungunya/efeitos dos fármacos , Antivirais/farmacologia , Antivirais/química , Antivirais/metabolismo , Febre de Chikungunya/virologia , Febre de Chikungunya/tratamento farmacológico , Metabolismo Secundário , Simulação de Dinâmica Molecular , Halogenação , Plantas/química , Simulação por Computador , Proteínas não Estruturais Virais/metabolismo , Proteínas não Estruturais Virais/química
2.
J Natl Cancer Inst ; 115(8): 981-988, 2023 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-37042724

RESUMO

BACKGROUND: The expansion of hematopoietic stem cells carrying recurrent somatic mutations, termed clonal hematopoiesis (CH), is common in elderly individuals and is associated with increased risk of myeloid malignancy and all-cause mortality. Though chemotherapy is a known risk factor for developing CH, how myelosuppressive therapies affect the short-term dynamics of CH remains incompletely understood. Most studies have been limited by retrospective design, heterogeneous patient populations, varied techniques to identifying CH, and analysis of single timepoints. METHODS: We examined serial samples from 40 older women with triple-negative or hormone receptor-positive breast cancer treated on the prospective ADjuVANt Chemotherapy in the Elderly trial to evaluate the prevalence and dynamics of CH at baseline and throughout chemotherapy (6 and 12 weeks). RESULTS: CH was detected in 44% of patients at baseline and in 53% at any timepoint. Baseline patient characteristics were not associated with CH. Over the course of treatment, mutations exhibited a variety of dynamics, including emergence, expansion, contraction, and disappearance. All mutations in TP53 (n = 3) and PPM1D (n = 4), genes that regulate the DNA damage response, either became detectable or expanded over the course of treatment. Neutropenia was more common in patients with CH, particularly when the mutations became detectable during treatment, and CH was significantly associated with cyclophosphamide dose reductions and holds (P = .02). CONCLUSIONS: Our study shows that CH is common, dynamic, and of potential clinical significance in this population. Our results should stimulate larger efforts to understand the biological and clinical importance of CH in solid tumor malignancies. TRIAL REGISTRATION: ClinicalTrials.gov (https://clinicaltrials.gov/ct2/show/NCT03858322). Clinical trial registration number: NCT03858322.


Assuntos
Neoplasias da Mama , Hematopoiese Clonal , Humanos , Feminino , Idoso , Hematopoiese Clonal/genética , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Estudos Retrospectivos , Hematopoese/genética , Mutação
3.
JCO Oncol Pract ; 19(7): 484-492, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37079865

RESUMO

PURPOSE: Family caregivers play an integral role in caring for older adults with cancer. Few studies have examined older adults with cancer and their family caregivers as a unit in a relationship or a dyad. Dyad congruence, or consistency in perspective, is relevant to numerous aspects of living with cancer, including the decision to enroll in a cancer clinical trial. METHODS: Semistructured interviews of 32 older women (age ≥ 70 years) with breast cancer and their family caregivers (16 dyads) were conducted at both academic and community settings from December 2019 to March 2021 to explore perceived facilitators and barriers to cancer trials. Dyad congruence was defined as aligned (matching) perspectives, and incongruence was defined as misaligned (nonmatching) perspectives. RESULTS: Five (31%) of 16 patients were age ≥80 years, 11 (69%) had nonmetastatic breast cancer, and 14 (88%) were treated in an academic setting. Six (38%) of 16 caregivers were in the 50-59 age group, 10 (63%) were female, and seven (44%) were daughters. Dyad congruence centered on the clinical benefit of trials and physician recommendation. However, compared with caregivers, patients were more motivated to contribute to science. Patients and caregivers also differed on the perceived extent to which the caregiver influenced enrollment. CONCLUSION: Older patients with cancer and their caregivers generally agree about the facilitators and barriers to cancer trial enrollment, but some perceptions are misaligned. Further research is needed to understand whether misaligned perspectives between patients and caregivers influence clinical trial participation of older adults with cancer.


Assuntos
Neoplasias da Mama , Médicos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Neoplasias da Mama/terapia , Cuidadores , Pessoa de Meia-Idade , Ensaios Clínicos como Assunto
4.
J Geriatr Oncol ; 14(1): 101349, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35970715

RESUMO

INTRODUCTION: Resilience, the ability to respond to stressors by maintaining or rapidly returning to normal homeostasis, serves as a new paradigm to improve the care of older adults. However, resilience research in oncology is nascent. We aimed to describe the current research landscape on physical, cognitive, and psychosocial resilience in older cancer patients. MATERIALS AND METHODS: We searched PubMed/MEDLINE from inception to January 28, 2022 for records with the terms "resilient OR resilience OR resiliency." We included studies that focused on persons over age 65 with cancer and assessed physical, cognitive, or psychological resilience. We excluded studies that did not report original data; did not have the full text available; assessed resilience on fewer than three time points; and published in non-English languages. Definitions and measures of resilience were extracted and categorized using qualitative analysis. RESULTS: Of 473 articles screened, we found 29 articles that met criteria for inclusion in our review. There was a high degree of heterogeneity in the definitions and measures of resilience. Resilience was defined as robustness/resistance to decline (n = 11), recovery from trauma/stressor (n = 7), and adaptive and proactive coping behaviors (n = 6). Ten papers did not define resilience. 21 studies utilized longitudinal analysis, five studies used randomized and nonrandomized control trials, and four studies assessed pre-post analysis. Stressors included cancer diagnosis (n = 18), chemotherapy (n = 3), radiation (n = 3), acute illness (n = 3), surgery (n = 2), and hematopoietic cell transplant (n = 1). DISCUSSION: Evidence for predictors and determinants of resilience in older adults with cancer is limited by the absence of standardized definitions and measurements. There is a fundamental need for a more precise definition, measures, and understanding of the physiologic mechanisms underlying the response to the physical, cognitive, and psychosocial stressors of cancer and its treatments.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Neoplasias , Resiliência Psicológica , Humanos , Idoso , Adaptação Psicológica , Neoplasias/psicologia
5.
Bioresour Technol ; 368: 128314, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36375698

RESUMO

Paddy straw (PS) and pine needles (PN) are one of the challenging biomasses in terms of disposal and compost making due to their high silica and tannin contents. Particulate air pollution, loss of biodiversity and respiratory impairments are some of disastrous outcomes caused by burning. However, high percentage of cellulose and hemicellulose makes them potential substrate for paper and pulp industries. The main aim of work was to study and utilize a combinatorial approach of weak chemical treatment and lignin degrading fungal species as agents of effective production of lignin modifying enzymes (LME's) for lignin depolymerisation from the biomasses. Phanerochaete chrysosporium was found to be the best degrader of lignin (47.11 % in PS + PN in 28 days) with maximum LME's production between 10th-17th days. Efficient lignin degradation in the PS and PN biomass will aid further application in pulp production supporting the transition to a circular economy in a greener way.


Assuntos
Lignina , Phanerochaete , Lignina/metabolismo , Biomassa , Phanerochaete/metabolismo , Celulose/metabolismo , Metabolismo Secundário
6.
J Geriatr Oncol ; 14(1): 101377, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36163163

RESUMO

INTRODUCTION: Older adults with breast cancer receiving neo/adjuvant chemotherapy are at high risk for poor outcomes and are underrepresented in clinical trials. The ADVANCE (ADjuVANt Chemotherapy in the Elderly) trial evaluated the feasibility of two neo/adjuvant chemotherapy regimens in parallel-enrolling cohorts of older patients with human epidermal growth factor receptor 2-negative breast cancer: cohort 1-triple-negative; cohort 2-hormone receptor-positive. MATERIALS AND METHODS: Adults age ≥ 70 years with stage I-III breast cancer warranting neo/adjuvant chemotherapy were enrolled. Cohort 1 received weekly carboplatin (area under the curve 2) and weekly paclitaxel 80 mg/m2 for twelve weeks; cohort 2 received weekly paclitaxel 80 mg/m2 plus every-three-weekly cyclophosphamide 600 mg/m2 over twelve weeks. The primary study endpoint was feasibility, defined as ≥80% of patients receiving ≥80% of intended weeks/doses of therapy. All dose modifications were applied per clinician discretion. RESULTS: Forty women (n = 20 per cohort) were enrolled from March 25, 2019 through August 3, 2020 from three centers; 45% and 35% of patients in cohorts 1 and 2 were age > 75, respectively. Neither cohort achieved targeted thresholds for feasibility. In cohort 1, eight (40.0%) met feasibility (95% confidence interval [CI] = 19.1-63.9%), while ten (50.0%) met feasibility in cohort 2 (95% CI = 27.2-72.8). Neutropenia was the most common grade 3-4 toxicity (cohort 1-65%, cohort 2-55%). In cohort 1, 80% and 85% required ≥1 dose holds of carboplatin and/or paclitaxel, respectively. In cohort 2, 10% required dose hold(s) for cyclophosphamide and/or 65% for paclitaxel. DISCUSSION: In this pragmatic pilot examining chemotherapy regimens in older adults with breast cancer, neither regimen met target goals for feasibility. Developing efficacious and tolerable regimens for older patients with breast cancer who need chemotherapy remains an important goal. CLINICALTRIALS: gov Identifier: NCT03858322.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Idoso , Neoplasias da Mama/tratamento farmacológico , Carboplatina , Projetos Piloto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Paclitaxel , Quimioterapia Adjuvante , Ciclofosfamida
8.
Molecules ; 27(17)2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36080385

RESUMO

Vitamin D's role in combating the SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2), the virus causing COVID-19, has been established in unveiling viable inhibitors of COVID-19. The current study investigated the role of pre and pro-vitamin D bioactives from edible mushrooms against Mpro and PLpro proteases of SARS-CoV-2 by computational experiments. The bioactives of mushrooms, specifically ergosterol (provitamin D2), 7-dehydrocholesterol (provitamin-D3), 22,23-dihydroergocalciferol (provitamin-D4), cholecalciferol (vitamin-D3), and ergocalciferol (vitamin D2) were screened against Mpro and PLpro. Molecular docking analyses of the generated bioactive protease complexes unravelled the differential docking energies, which ranged from -7.5 kcal/mol to -4.5 kcal/mol. Ergosterol exhibited the lowest binding energy (-7.5 kcal/mol) against Mpro and PLpro (-5.9 kcal/mol). The Molecular Mechanics Poisson-Boltzmann Surface Area (MMPBSA) and MD simulation analyses indicated that the generated complexes were stable, thus affirming the putative binding of the bioactives to viral proteases. Considering the pivotal role of vitamin D bioactives, their direct interactions against SARS-CoV-2 proteases highlight the promising role of bioactives present in mushrooms as potent nutraceuticals against COVID-19.


Assuntos
Agaricales , Tratamento Farmacológico da COVID-19 , Agaricales/metabolismo , Endopeptidases/metabolismo , Ergosterol , Humanos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Peptídeo Hidrolases/química , Inibidores de Proteases/química , Provitaminas , SARS-CoV-2 , Proteínas não Estruturais Virais/metabolismo , Vitamina D/farmacologia
9.
Microb Pathog ; 168: 105610, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35662673

RESUMO

The cell wall degrading enzymes polygalacturonase (PG) secreted by Fusarium oxysporum f. sp. radicis-lycopersici (FOL) is testified to trigger Fusarium crown and root rot disease in tomato crops; instigated due to the degradation of the pectin. Trichoderma sp. is documented as a potential biocontrol agent playing a pivotal role in plant health and disease management. An in-silico approach employing homology modelling, molecular docking, molecular dynamics (MD) simulation and MMPBSA was employed to assess the prospective role of bioactives produced by Trichoderma sp. in combating the PG2 enzyme. The studies revealed that amongst the wide range of bioactives screened, Trichodermamide B produced by T. harzianum and Viridin, Virone, and Trichosetin produced by T. virens emerged as the potential inhibitors of the PG2. Docking results revealed that the complexes possessed most stable energy for Trichodermamide B (-8.1 kcal/mol) followed by Viridin (-7.7 kcal/mol), Virone (-7.1 kcal/mol), and Trichosetin (-7 kcal/mol), respectively. Interaction studies of FOL with T. virens and T. harzianum reported an inhibition of 83.33% and 75.87%, respectively. The structural rigidity and stability of the docked complex was confirmed through MD simulations evaluated across multiple descriptors from the simulation trajectories. Further, MMPBSA analysis validated the results that binding of the enzyme to the screened ligands was spontaneous. The study unravels new insights on the versatile potential of Trichoderma sp. Bioactives as a prospective agent for the inhibition of cell-wall degrading enzymes secreted by phytopathogens. The proposed study can be implemented for design of bioformulations that serve the role of biopesticide, promising a sustainable alternate to chemical-based products.


Assuntos
Fusarium , Trichoderma , Parede Celular , Fusarium/metabolismo , Simulação de Acoplamento Molecular , Doenças das Plantas/prevenção & controle , Poligalacturonase , Estudos Prospectivos , Trichoderma/metabolismo
10.
J Biomol Struct Dyn ; 40(16): 7535-7544, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-33719892

RESUMO

Tomatinase; a saponin detoxification enzyme produced by Fusarium oxysporumf.sp. lycopersici is reported as a causative agent for wilting disease in tomato crops. The disease is instigated by inhibiting the activity of α-tomatine. Trichoderma spp. widely used as biocontrol agent play an essential role in plant growth and pathogen control. In the current study, an in-silico approach using substrate docking, molecular dynamics and MM/PBSA analysis was used to evaluate the potential role of bioactive metabolites produced by Trichoderma spp. The study aims to establish the efficacy of catalytic tendency of the bioactive metabolites to combat the effect of tomatinase enzyme employing α-tomatine as the substrate. By means of the integrated molecular modeling approach; novel bioactive metabolites namely, Trichodermamide B, Trichosetin and Virone were found to be the potential inhibitors against tomatinase enzyme secreted by Fusarium oxysporum f.sp. lycopersici. Molecular dynamic (MD) simulations displayed that the screened ligands bound tomatinase during 150 ns of MD simulations. Furthermore, the (MM-PBSA) free energy calculations depicted that screened molecules possess stable and favorable energies for Trichodermamide B (-7.1 kcal/mol), Trichosetin (-7.4 kcal/mol) and Virone (-7.9 kcal/mol) thereby instigating robust binding with the enzyme's binding site. The results attained in this study, reflects that these bioactive metabolites may serve as potential substrates to control and inhibit the tomatinase enzyme; playing an integral role in combating the wilt disease.Communicated by Ramaswamy H. Sarma.


Assuntos
Fusarium , Solanum lycopersicum , Trichoderma , Glicosídeo Hidrolases/metabolismo , Solanum lycopersicum/metabolismo
11.
J Environ Manage ; 297: 113278, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34325372

RESUMO

The present investigation was performed to valorize paddy straw (PS) based silica (Si) rich Spent Mushroom Substrate (SMS) of Pleurotus ostreatus for Plant Nutrient and Disease Management in wilt (caused by F. oxysporum f. sp. lycopersici) susceptible tomato plant F1 Hybrid King 180. Raw PS and SMS generated by P. ostreatus cultivated on PS only, and PS amended with 5% soybean cake (SC) were bio-fortified with Trichoderma asperellum (TA). SMS (PS+ 5% SC) was found supporting the growth of T. asperellum to an extent of 12.37 × 1013 conidia/g substrate. GC-MS analysis of SMS detected several bioactive metabolites like Palmitic acid, Oleic acid, Methyl linoleate, Stigmasterol, etc., known for plant health management. Bioformulations were developed employing Press Mud (PM) and Talcum Powder (TP) as carrier materials. Among the different bioformulations tested in pots study; SMS (PS+ 5% SC) SiTAPM, collectively named as TF-I, provided improved levels of morpho-biochemical and nutritional parameters, i.e., Plant Biomass (2.27 folds), Root Volume (1.75 folds), Chlorophyll (2.66 folds), Carotenoids (2.42 folds), Number of Fruits (1.76 folds), Fruit Biomass (2.02 folds), Total Soluble Sugars (2.32 folds), Total Soluble Proteins (1.70 folds), and nutraceutical parameters as Lycopene (1.42 folds), ß-carotene (2.65 folds) and Ascorbic Acid (1.54 folds), along with significant (p < 0.05) reduction in the Disease Severity Index (84.34%-21.23%), over the pathogen affected plant taken as control. The fruits and leaves garnered under TF-I displayed Total Polyphenol Content (TPC) of 74.5 and 126.9 mg g-1 gallic acid, respectively, with 83.73% DPPH and 72.25% FRAP activity, indicating the elicitation of antioxidant properties in tomato fruits. EDS analyses showed 21.53% Si in SMS, and plant mapping investigation indicated a substantial accumulation of Si, which is well conceded to promote growth, disease resistance, and antioxidant parameters. The study also endorsed the use of PM over TP, as TF-I recorded an acceptable conidial count (2.22 × 108 cfu/g) towards the end of six months storage period over other bioformulations. Overall, the study envisages the development and application of innovative methodology (TF-I), offering an eco-friendly alternative for producing quality crops and a sustainable solution to waste management, thus delivering a holistic contribution towards the circular economy.


Assuntos
Agaricales , Trichoderma , Gerenciamento Clínico , Hypocreales , Nutrientes , Dióxido de Silício
13.
Front Microbiol ; 12: 812466, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35145499

RESUMO

A growing body of scientific evidence supports the notion that gut microbiota plays a key role in the regulation of various physiological and pathological processes related to human health. Recent findings have now established that gut microbiota also contributes to the regulation of bone homeostasis. Studies on animal models have unraveled various underlying mechanisms responsible for gut microbiota-mediated bone regulation. Normal gut microbiota is thus required for the maintenance of bone homeostasis. However, dysbiosis of gut microbiota communities is reported to be associated with several bone-related ailments such as osteoporosis, rheumatoid arthritis, osteoarthritis, and periodontitis. Dietary interventions in the form of probiotics, prebiotics, synbiotics, and postbiotics have been reported in restoring the dysbiotic gut microbiota composition and thus could provide various health benefits to the host including bone health. These dietary interventions prevent bone loss through several mechanisms and thus could act as potential therapies for the treatment of bone pathologies. In the present review, we summarize the current knowledge of how gut microbiota and its derived microbial compounds are associated with bone metabolism and their roles in ameliorating bone health. In addition to this, we also highlight the role of various dietary supplements like probiotics, prebiotics, synbiotics, and postbiotics as promising microbiota targeted interventions with the clinical application for leveraging treatment modalities in various inflammatory bone pathologies.

14.
J Clin Med ; 9(5)2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-32455877

RESUMO

Cancer is a disease associated with aging. As the US population ages, the number of older adults with cancer is projected to dramatically increase. Despite this, older adults remain vastly underrepresented in research that sets the standards for cancer treatments and, consequently, clinicians struggle with how to interpret data from clinical trials and apply them to older adults in practice. A combination of system, clinician, and patient barriers bar opportunities for trial participation for many older patients, and strategies are needed to address these barriers at multiple fronts, five of which are offered here. This review highlights the need to (1) broaden eligibility criteria, (2) measure relevant end points, (3) expand standard trial designs, (4) increase resources (e.g., institutional support, interdisciplinary care, and telehealth), and (5) develop targeted interventions (e.g., behavioral interventions to promote patient enrollment). Implementing these solutions requires a substantial investment in engaging and collaborating with community-based practices, where the majority of older patients with cancer receive their care. Multifaceted strategies are needed to ensure that older patients with cancer, across diverse healthcare settings, receive the highest-quality, evidence-based care.

15.
Comput Biol Chem ; 56: 1-6, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25733445

RESUMO

Bacteriocins are antimicrobial peptides which are ribosomally synthesized by mainly all bacterial species. LABs (lactic acid bacteria) are a diverse group of bacteria that include around 20 genera of various species. Though LABs have a tremendous potential for production of anti-microbial peptides, this group of bacteria is still underexplored for bacteriocins. To study the diversity among bacteriocin encoding clusters and the putative bacteriocin precursors, genome mining was performed on 20 different species of LAB not reported to be bacteriocin producers. The phylogenetic tree of gyrB, rpoB, and 16S rRNA were constructed using MEGA6 software to analyze the diversity among strains. Putative bacteriocins operons identified were found to be diverse and were further characterized on the basis of physiochemical properties and the secondary structure. The presence of at least two cysteine residues in most of the observed putative bacteriocins leads to disulphide bond formation and provide stability. Our data suggests that LABs are prolific source of low molecular weight non modified peptides.


Assuntos
Bacteriocinas/genética , Lactobacillus/genética , Leuconostoc/genética , Streptococcus/genética , Bacteriocinas/química , Bacteriocinas/metabolismo , DNA Bacteriano/genética , Genômica , Ácido Láctico/metabolismo , Lactobacillus/química , Lactobacillus/metabolismo , Leuconostoc/química , Leuconostoc/metabolismo , Família Multigênica , Filogenia , Estrutura Secundária de Proteína , RNA Ribossômico 16S/genética , Streptococcus/química , Streptococcus/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...