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1.
Nature ; 597(7878): 732-737, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34526717

RESUMEN

Epidermal growth factor receptor (EGFR) mutations typically occur in exons 18-21 and are established driver mutations in non-small cell lung cancer (NSCLC)1-3. Targeted therapies are approved for patients with 'classical' mutations and a small number of other mutations4-6. However, effective therapies have not been identified for additional EGFR mutations. Furthermore, the frequency and effects of atypical EGFR mutations on drug sensitivity are unknown1,3,7-10. Here we characterize the mutational landscape in 16,715 patients with EGFR-mutant NSCLC, and establish the structure-function relationship of EGFR mutations on drug sensitivity. We found that EGFR mutations can be separated into four distinct subgroups on the basis of sensitivity and structural changes that retrospectively predict patient outcomes following treatment with EGFR inhibitors better than traditional exon-based groups. Together, these data delineate a structure-based approach for defining functional groups of EGFR mutations that can effectively guide treatment and clinical trial choices for patients with EGFR-mutant NSCLC and suggest that a structure-function-based approach may improve the prediction of drug sensitivity to targeted therapies in oncogenes with diverse mutations.


Asunto(s)
Antineoplásicos/farmacología , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Afatinib/uso terapéutico , Animales , Carcinoma de Pulmón de Células no Pequeñas/genética , Línea Celular Tumoral , Reposicionamiento de Medicamentos , Resistencia a Antineoplásicos , Receptores ErbB/genética , Exones , Femenino , Humanos , Neoplasias Pulmonares/genética , Ratones , Simulación del Acoplamiento Molecular , Mutación , Relación Estructura-Actividad
2.
Bioinformatics ; 39(1)2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36648331

RESUMEN

MOTIVATION: Multilevel molecular profiling of tumors and the integrative analysis with clinical outcomes have enabled a deeper characterization of cancer treatment. Mediation analysis has emerged as a promising statistical tool to identify and quantify the intermediate mechanisms by which a gene affects an outcome. However, existing methods lack a unified approach to handle various types of outcome variables, making them unsuitable for high-throughput molecular profiling data with highly interconnected variables. RESULTS: We develop a general mediation analysis framework for proteogenomic data that include multiple exposures, multivariate mediators on various scales of effects as appropriate for continuous, binary and survival outcomes. Our estimation method avoids imposing constraints on model parameters such as the rare disease assumption, while accommodating multiple exposures and high-dimensional mediators. We compare our approach to other methods in extensive simulation studies at a range of sample sizes, disease prevalence and number of false mediators. Using kidney renal clear cell carcinoma proteogenomic data, we identify genes that are mediated by proteins and the underlying mechanisms on various survival outcomes that capture short- and long-term disease-specific clinical characteristics. AVAILABILITY AND IMPLEMENTATION: Software is made available in an R package (https://github.com/longjp/mediateR). SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Asunto(s)
Neoplasias , Proteogenómica , Humanos , Análisis de Mediación , Simulación por Computador , Programas Informáticos , Neoplasias/genética
3.
Org Biomol Chem ; 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39139027

RESUMEN

Despite the extensive use of N-heteroarenes in pharmaceuticals and natural products, efficient methods for selective alkylation at the C-4 position of 2-pyridone are scarce. We developed an enantioselective Michael addition of 3-hydroxy-2-pyridone to nitroolefins at the C-4 position using cinchona-derived bifunctional squaramide organocatalysts, achieving up to 95% yield and >99% ee. This selectivity is driven by the bifunctional organocatalysts' hydrogen bonding interactions with 3-hydroxy-2-pyridone and nitroolefins under mild conditions. This method demonstrates the Michael reaction's versatility with various nitroolefins, providing a sustainable approach for synthesizing chiral N-heteroarenes with high enantioselectivity and regioselectivity under environmentally friendly conditions.

4.
BMC Infect Dis ; 24(1): 813, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39134980

RESUMEN

BACKGROUND: Diphtheria is a re-emerging infectious disease and public health concern worldwide and in Vietnam with increasing cases in recent years. This study aimed to assess the anti-diphtheria toxoid antibodies status in Khanh Hoa Province and identify factors contributing to the vaccination policy in the south-central coast of Vietnam. METHODS: This was a cross-sectional study to evaluate the seroprevalence of anti-diphtheria toxoid antibodies among 1,195 participants, aged 5 - 40 years in Khanh Hoa Province, Vietnam. Immunoglobulin G antibody levels against diphtheria were detected using a commercial anti-diphtheria toxoid enzyme-linked immunosorbent assay (SERION ELISA classic Diphtheria Immunoglobulin G) and were categorized following the World Health Organization guidelines. RESULTS: The mean anti-diphtheria toxoid antibody levels were 0.07 IU/ml (95% Confidence Interval: 0.07-0.08). Anti-diphtheria toxoid antibody levels were found to be associated with age and history of diphtheria vaccination. The 5-15 years age group had the highest levels (0.09 IU/ml), while the older age group had the lowest antibody level (p < 0.001). Individuals who received three doses (adjusted Odds ratio: 2.34, 95%CI: 1.35 - 4.07) or 4+ doses (adjusted Odds ratio: 2.45, 95%CI: 1.29 - 4.64) had a higher antibody level compared to those who received only one dose regardless of age. CONCLUSION: It is crucial to promote routine vaccination coverage to over 95% for children under one year of age with three primary doses of the diphtheria-containing vaccine, including additional doses at 18 months and 7 years of age. Booster doses should be promoted and administered to adolescents and adults every 10 years.


Asunto(s)
Anticuerpos Antibacterianos , Toxoide Diftérico , Difteria , Vacunación , Humanos , Estudios Transversales , Vietnam/epidemiología , Adolescente , Adulto , Estudios Seroepidemiológicos , Masculino , Niño , Femenino , Adulto Joven , Difteria/prevención & control , Difteria/inmunología , Difteria/epidemiología , Anticuerpos Antibacterianos/sangre , Preescolar , Toxoide Diftérico/inmunología , Toxoide Diftérico/administración & dosificación , Vacunación/estadística & datos numéricos , Inmunoglobulina G/sangre , Ensayo de Inmunoadsorción Enzimática
5.
BMC Womens Health ; 24(1): 154, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38438927

RESUMEN

BACKGROUND: Chronic stress and diseases occur more frequently in middle-aged compared to younger women and this is often the result of physical, psychological and socio-economic changes. These health consequences reduce lower body muscle mass and flexibility, leading to generalized impairments in functional movement and balance. Dynamic Neuromuscular Stabilization (DNS) training using the inertial load of water is known for its positive impact on functional strength improvement and muscle stabilization. OBJECTIVE: This study aimed to determine the effect of DNS training using inertial water loads on functional movement and postural sway in middle-aged women. METHOD: A sample of 24 middle-aged women participated in the study and were randomly divided into two groups: the experimental group, n = 12 (age: 58.33 ± 1.48 yrs, height: 162.16 ± 1.27 cm, weight: 61.77 ± 2.21 kg) and control group, n = 12 (age: 59.58 ± 1.13 yrs, height: 160.1 ± 1.13 cm, weight: 57.51 ± 1.12 kg). Center of Pressure (COP), moving distance, Root Mean Square (RMS), movement area and Functional Movement Screen (FMS) were conducted and analyzed pre- and post-examination. Participants engaged in the DNS training regimen, which utilized the inertial load of water, for 60 min each session, conducted twice weekly for 12 weeks. RESULTS: There were significant differences in the COP distance (p < 0.001), RMS (p < 0.05), COP area and FMS test (p < 0.001) in the pre-post comparison of each group. And significant differences were found in COP distance (p < 0.05), RMS (p < 0.05), COP area (p < 0.05) and FMS test (p < 0.05) between groups. The DNS training improved the dynamic stability of single-leg standing, torso stability and functional movement in middle-aged women. CONCLUSION: DNS training programs using the inertial load of water have been shown to be effective in movement improvement and posture retention ability, which is beneficial for functional movement, equilibrium strategy, and dynamic stability of middle-aged women. Furthermore, the DNS training method designed in this study can be useful for trainees who require posture correction in a safe and effective way regardless of their age and gender.


Asunto(s)
Terapia por Ejercicio , Examen Físico , Persona de Mediana Edad , Femenino , Humanos , Agua
6.
Artículo en Inglés | MEDLINE | ID: mdl-38642325

RESUMEN

BACKGROUND: In children suspected of asthma, diagnosis is confirmed via variable expiratory airflow limitation. However, there is no single gold standard test for diagnosing asthma. OBJECTIVE: This study aimed to evaluate the pulmonary function characteristics in children suspected of asthma without bronchodilator response (BDR) and bronchial hyperresponsiveness (BHR). METHODS: We utilized two separate real-world retrospective observational cohorts of children who underwent both spirometry and bronchial provocation testing for asthma. Spirometry parameters were collected and compared between definite asthma, probable asthma, and non-asthma groups. The original cohort comprised 1199 children who visited the Severance Hospital (Seoul, Korea) between January 2017 and December 2019. The external cohort included 105 children who visited the Gangnam Severance Hospital between January 2019 and December 2019. RESULTS: Probable asthma accounted for 16.8% and 32.4% of the original and external cohorts, respectively. This group showed a significantly higher FeNO level and prevalence of allergic sensitization. Baseline forced expiratory volume in 1 second (FEV1), FEV1/forced vital capacity (FVC), forced expiratory flow at 25-75% of FVC (FEF25-75), and FEF75 showed stepwise decrements from non-asthma, probable asthma, to definite asthma patients (P < 0.001). The probable asthma group showed significantly higher odds of abnormal FEV1/FVC (OR, 2.24 [95%CI, 1.43-3.52])and FEF25-75 (2.05 [1.13-3.73]) than the non-asthma group and lower odds of abnormal FEV1(0.05 [0.01-0.19]),FEV1 /FVC (0.27 [0.18-0.41]), FEF25-75 (0.17 [0.11-0.28]), and FEF75 (0.14 [0.08-0.24]) compared to the definite asthma group. The external cohort was consistent with the original cohort. CONCLUSION: We show evidence of airway dysfunction in children for whom a high clinical suspicion of asthma exists without evidence of BDR and BHR. Repeated pulmonary function tests that closely monitor for subtle lung function impairments and active utilization of additional tests, such as allergic screening and FeNO, should be considered to close the gap in diagnosing asthma.

7.
Hepatology ; 76(6): 1634-1648, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35349735

RESUMEN

BACKGROUND AND AIMS: Although many studies revealed transcriptomic subtypes of HCC, concordance of the subtypes are not fully examined. We aim to examine a consensus of transcriptomic subtypes and correlate them with clinical outcomes. APPROACH AND RESULTS: By integrating 16 previously established genomic signatures for HCC subtypes, we identified five clinically and molecularly distinct consensus subtypes. STM (STeM) is characterized by high stem cell features, vascular invasion, and poor prognosis. CIN (Chromosomal INstability) has moderate stem cell features, but high genomic instability and low immune activity. IMH (IMmune High) is characterized by high immune activity. BCM (Beta-Catenin with high Male predominance) is characterized by prominent ß-catenin activation, low miRNA expression, hypomethylation, and high sensitivity to sorafenib. DLP (Differentiated and Low Proliferation) is differentiated with high hepatocyte nuclear factor 4A activity. We also developed and validated a robust predictor of consensus subtype with 100 genes and demonstrated that five subtypes were well conserved in patient-derived xenograft models and cell lines. By analyzing serum proteomic data from the same patients, we further identified potential serum biomarkers that can stratify patients into subtypes. CONCLUSIONS: Five HCC subtypes are correlated with genomic phenotypes and clinical outcomes and highly conserved in preclinical models, providing a framework for selecting the most appropriate models for preclinical studies.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Masculino , Femenino , Carcinoma Hepatocelular/patología , beta Catenina/genética , Neoplasias Hepáticas/patología , Consenso , Proteómica , Genómica , Fenotipo
8.
Environ Res ; 227: 115706, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-36931381

RESUMEN

The catalytic ozonation of methylethylketone (MEK) was performed at the room temperature (25 °C) using the synthesized Mn and Cu-loaded zeolite (ZSM-5, SiO2/Al2O3 = 80) catalysts. The ZSM-5 zeolite was used as a porous support material due to the large surface area and high capacity for adsorption of volatile organic compounds. Since Mn and Cu-loaded zeolite catalysts were effective for the catalytic ozonation of VOCs such as MEK, according to the loaded concentration of Mn and Cu, there are four types of metal loaded ZSM5 catalysts synthesized [5 wt% Mn/ZSM-5, 5 wt% Cu/ZSM-5, 5 wt% Mn-1 wt% Cu/ZSM-5 (5Mn1CuZSM), and 5 wt% Cu-1 wt% Mn/ZSM-5]. The catalytic efficiency for the removal of MEK and ozonation using the different catalysts was also studied. Based on various experimental analysis processes, the characteristics of the synthesized catalysts were explored and the removal efficiencies of MEK and O3 together with the COx concentration generated from the destruction of MEK and O3 were explored. The results for the decomposition of MEK and O3 at the room temperature indicated that the Mn dominant ZSM-5 catalysts showed better efficiency for the conversion of MEK and O3. The 5 wt% Mn/ZSM-5 outweighed the rest of them for the removal of MEK while the 5Mn1CuZSM showed the best catalytic reactivity for the conversion of O3 and the CO2 selectivity. It was ascertained that during the reaction time of catalyst and reactants of 120 min the Mn dominantly deposited bimetallic catalyst, 5Mn1CuZSM, was determined as the most effective for the removal of MEK and O3 due to the high capability of production of Mn3+ species and more available adsorbed oxygen sites compared to the other catalysts. Finally, the durability measurement for the 5Mn1CuZSM catalyst was performed together with the produced CO and CO2 concentration for 420 min.


Asunto(s)
Ozono , Zeolitas , Dióxido de Silicio , Dióxido de Carbono , Porosidad , Quinasas de Proteína Quinasa Activadas por Mitógenos , Catálisis
9.
Am J Hum Biol ; 35(12): e23962, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37489847

RESUMEN

OBJECTIVES: This study aimed to perform latent profile analysis (LPA) in older adult women with metabolic syndrome to extract a group according to their characteristics while controlling for body composition, blood lipid levels, and vascular function. The study also examined the relationship between different variables. METHODS: The participants were 35 women aged ≥65 years, who met the Korean female standards for metabolic syndrome. Blood collection, blood pressure measurements, and vascular function measurements were performed. LPA and multigroup path analysis (MGPA) were performed to statistically analyze the effects of body composition on blood lipid levels and vascular function in older adult women with metabolic syndrome. Mplus 8.3 and jamovi 2.0.0 were used for the analyses, and the control significance level was set at .05. RESULTS: The participants were divided into the following three groups: (G1) metabolically unhealthy participants with normal weight, (G2) normal-weight participants with arteriosclerosis, and (G3) obese but metabolically healthy participants (G3). The effect of body composition on blood lipid levels showed a significant difference only in G1. The effect of body composition on vascular function was influenced by various variables in G1 and G3, while G1 showed a higher explanatory power. CONCLUSIONS: The MGPA results showed that the relationship between variables differs depending on the group. Therefore, the metabolic syndrome should be studied by subdividing it and confirming the characteristics of the classified groups, such as normal-weight but metabolically unhealthy individuals and obese but metabolically healthy individuals.


Asunto(s)
Síndrome Metabólico , Femenino , Humanos , Anciano , Índice de Masa Corporal , Obesidad , Lípidos , Composición Corporal , Factores de Riesgo
10.
BMC Nephrol ; 24(1): 102, 2023 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-37085769

RESUMEN

The prevalence of chronic kidney disease (CKD) is steadily increasing, and it is a global health burden. Exercise has been suggested to improve physical activity and the quality of life in patients with CKD, eventually reducing mortality. This study investigated the change in physical performance after exercise in dialysis-dependent patients with CKD and analyzed differentially expressed proteins before and after the exercise. Plasma samples were collected at enrollment and after 3 months of exercise. Liquid chromatography with tandem mass spectrometry analysis and data-independent acquisition results were analyzed to determine the significantly regulated proteins. A total of 37 patients on dialysis were recruited, and 16 were randomized to exercise for 3 months. The hand grip strength and the walking speed significantly improved in the exercise group. Proteome analysis revealed 60 significantly expressed proteins after 3 months of exercise. In the protein functional analysis, the significantly expressed proteins were involved in the immune response. Also, some of the key significantly expressed proteins [(M Matrix metallopeptidase 9 (MMP-9), Activin A Receptor Type 1B (ACVR1B), Fetuin B (FETUB)] were validated via an enzyme-linked immunosorbent assay. Our results showed that exercise in dialysis-dependent patients with CKD could improve their physical performance. These results indicated that this beneficial effect of exercise in these populations could be associated with immune response.


Asunto(s)
Fallo Renal Crónico , Insuficiencia Renal Crónica , Humanos , Diálisis Renal/métodos , Fuerza de la Mano , Proteómica , Calidad de Vida , Ejercicio Físico/fisiología , Insuficiencia Renal Crónica/terapia
11.
Drug Dev Res ; 84(7): 1537-1552, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37571819

RESUMEN

FAM64A is a mitogen-induced regulator of the metaphase and anaphase transition. Here, we found that FAM64A messenger RNA (mRNA) and protein expression levels were higher in gastric cancer tissue than in normal mucosa (p < .05). FAM64A methylation was negatively correlated with FAM64A mRNA expression (p < .05). The differentially expressed genes of FAM64A were mainly involved in digestion, potassium transporting or exchanging ATPase, contractile fibers, endopeptidase, and pancreatic secretion (p < .05). The FAM64A-related genes were principally categorized into ubiquitin-mediated proteolysis, cell cycle, chromosome segregation and mitosis, microtubule binding and organization, metabolism of amino acids, cytokine receptors, lipid droplet, central nervous system, and collagen trimer (p < .05). FAM64A protein expression was lower in normal gastric mucosa than intestinal metaplasia, adenoma, and primary cancer (p < .05), negatively correlated with older age, T stage, lymphatic and venous invasion, tumor, node, metastasis stage, and dedifferentiation (p < .05), and associated with a favorable overall survival of gastric cancer patients. FAM64A overexpression promoted proliferation, antiapoptosis, migration, invasion, and epithelial-mesenchymal transition via the EGFR/Akt/mTOR/NF-κB, while the opposite effect was observed for FAM64A knockdown. FAM64A also induced chemoresistance directly or indirectly through lipid droplet formation via ING5. These results suggested that upregulation of FAM64A expression might induce aggressive phenotypes, leading to gastric carcinogenesis and its subsequent progression. Thus, FAM64A could be regarded as a prognosis biomarker and a target for gene therapy.


Asunto(s)
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/genética , Resistencia a Antineoplásicos/genética , Gotas Lipídicas/metabolismo , Gotas Lipídicas/patología , Regulación Neoplásica de la Expresión Génica , Biomarcadores , Proliferación Celular/genética , ARN Mensajero , Terapia Genética , Línea Celular Tumoral , Movimiento Celular , Pronóstico
12.
Int J Cancer ; 150(12): 2025-2037, 2022 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-35133007

RESUMEN

Cyclin-dependent-kinase-4/6 inhibitor (CDK4/6i) plus endocrine therapy (ET) is standard of care for patients with advanced hormone receptor (HR)-positive, HER2-negative breast cancer (BC). The Breast Medical Oncology database at MD Anderson Cancer Center (MDACC) was analyzed to assess effectiveness of the CDK4/6i palbociclib plus ET compared to ET alone. From a total of 5402 advanced HR+ HER2- BC patients referred to MDACC between 1997 and 2020, we identified eligible patients who received palbociclib in combination with first-line (n = 778) and second-line (n = 410) ET. We further identified "control" patients who received ET alone in the first-line (n = 2452) and second-line (n = 1183) settings. Propensity score matching analysis was conducted to balance baseline demographic and clinical characteristics between palbociclib and control cohorts to assess the effect of palbociclib treatment on progression-free survival (PFS) and overall survival (OS). For propensity-matched-cohort in the first-line setting (n = 708), palbociclib group had significantly longer median PFS (17.4 vs 11.1 months; P < .0001) compared to controls. Median OS (44.3 vs 40.2 months) did not show a statistically significant benefit in the first line setting. However, in the second-line setting, with 380 propensity-matched-cohort, the palbociclib group had significantly longer PFS (10 vs 5 months, P < .0001) as well as OS (33 vs 24 months; P < .022), compared to controls. We conclude that in this single center analysis of a large cohort of metastatic HR+ HER2- BC patients, palbociclib in combination with ET was associated with improved PFS in both first-line and second-line settings and OS in the second-line setting compared to ET alone cohort.


Asunto(s)
Neoplasias de la Mama , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Femenino , Humanos , Piperazinas , Inhibidores de Proteínas Quinasas/uso terapéutico , Piridinas , Receptor ErbB-2 , Receptores de Estrógenos
13.
J Immunol ; 204(3): 718-725, 2020 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-31836656

RESUMEN

The variable lymphocyte receptor (VLR) mediates the humoral immune response in jawless vertebrates, including lamprey (Petromyzon marinus) and hagfish (Eptatretus burgeri). Hagfish VLRBs are composed of leucine-rich repeat (LRR) modules, conjugated with a superhydrophobic C-terminal tail, which contributes to low levels of expression in recombinant protein technology. In this study, we screened Ag-specific VLRBs from hagfish immunized with nervous necrosis virus (NNV). The artificially multimerized form of VLRB was constructed using a mammalian expression system. To enhance the level of expression of the Ag-specific VLRB, mutagenesis of the VLRB was achieved in vitro through domain swapping of the LRR C-terminal cap and variable LRR module. The mutant VLRB obtained, with high expression and secretion levels, was able to specifically recognize purified and progeny NNV, and the Ag binding ability of this mutant was increased by at least 250-fold to that of the nonmutant VLRB. Furthermore, preincubation of the Ag-specific VLRB with NNV reduced the infectivity of NNV in E11 cells in vitro, and in vivo experiment. Our results suggest that the newly developed Ag-specific VLRB has the potential to be used as diagnostic and therapeutic reagents for NNV infections in fish.


Asunto(s)
Enfermedades de los Peces/inmunología , Anguila Babosa/inmunología , Linfocitos/inmunología , Nodaviridae/fisiología , Infecciones por Virus ARN/inmunología , Animales , Anticuerpos Neutralizantes/metabolismo , Anticuerpos Antivirales/metabolismo , Línea Celular , Proteínas de Peces/genética , Proteínas de Peces/metabolismo , Inmunización , Lampreas , Mutación/genética , Petromyzon , Receptores de Antígenos/genética , Receptores de Antígenos/metabolismo
14.
J Appl Microbiol ; 132(4): 2746-2759, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35019198

RESUMEN

AIM: Bacteria naturally produce membrane vesicles (MVs), which have been shown to contribute to the spread of multi-drug resistant bacteria (MDR) by delivering antibiotic-resistant substances to antibiotic-susceptible bacteria. Here, we aim to show that MVs from Gram-positive bacteria are capable of transferring ß-lactam antibiotic-resistant substances to antibiotic-sensitive Gram-negative bacteria. MATERIALS AND METHODS: MVs were collected from a methicillin-resistant strain of Staphylococcus aureus (MRSA) and vesicle-mediated fusion with antimicrobial-sensitive Escherichia coli (RC85). It was performed by exposing the bacteria to the MVs to develop antimicrobial-resistant E. coli (RC85-T). RESULTS: The RC85-T exhibited a higher resistance to ß-lactam antibiotics compared to the parent strain. Although the secretion rates of the MVs from RC85-T and the parent strain were nearly equal, the ß-lactamase activity of the MVs from RC85-T was 12-times higher than that of MVs from the parent strain, based on equivalent protein concentrations. Moreover, MVs secreted by RC85-T were able to protect ß-lactam-susceptible E. coli from ß-lactam antibiotic-induced growth inhibition in a dose-dependent manner. CONCLUSION: MVs play a role in transferring substances from Gram-positive to Gram-negative bacteria, shown by the release of MVs from RC85-T that were able to protect ß-lactam-susceptible bacteria from ß-lactam antibiotics. SIGNIFICANCE AND IMPACT OF STUDY: MVs are involved in the emergence of antibiotic-resistant strains in a mixed bacterial culture, helping us to understand how the spread of multidrug-resistant bacteria could be reduced.


Asunto(s)
Antibacterianos , Staphylococcus aureus Resistente a Meticilina , Antibacterianos/metabolismo , Farmacorresistencia Bacteriana Múltiple , Escherichia coli , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus
15.
Mar Drugs ; 20(3)2022 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-35323470

RESUMEN

A great effort to discover new therapeutic ingredients is often initiated through the discovery of the existence of novel marine natural products. Since substances produced by the marine environment might be structurally more complex and unique than terrestrial natural products, there have been cases of misassignments of their structures despite the availability of modern spectroscopic and computational chemistry techniques. When it comes to refutation to erroneously or tentatively proposed structures empirical preparations through organic chemical synthesis has the greatest contribution along with close and sophiscated inspection of spectroscopic data. Herein, we analyzed the total synthetic studies that have decisively achieved in revelation of errors, ambiguities, or incompleteness of the isolated structures of marine natural products covering the period from 2018 to 2021.


Asunto(s)
Productos Biológicos/química , Técnicas de Química Sintética , Biología Marina , Estructura Molecular , Análisis Espectral
16.
Int J Mol Sci ; 23(24)2022 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-36555761

RESUMEN

Cysteine-cysteine chemokine receptor 5 (CCR5) has been discovered as a co-receptor for cellular entry of human immunodeficiency virus (HIV). Moreover, the role of CCR5 in a variety of cancers and various inflammatory responses was also discovered. Despite the fact that several CCR5 antagonists have been investigated in clinical trials, only Maraviroc has been licensed for use in the treatment of HIV patients. This indicates that there is a need for novel CCR5 antagonists. Keeping this in mind, the present study was designed. The active CCR5 inhibitors with known IC50 value were selected from the literature and utilized to develop a ligand-based common feature pharmacophore model. The validated pharmacophore model was further used for virtual screening of drug-like databases obtained from the Asinex, Specs, InterBioScreen, and Eximed chemical libraries. Utilizing computational methods such as molecular docking studies, molecular dynamics simulations, and binding free energy calculation, the binding mechanism of selected inhibitors was established. The identified Hits not only showed better binding energy when compared to Maraviroc, but also formed stable interactions with the key residues and showed stable behavior throughout the 100 ns MD simulation. Our findings suggest that Hit1 and Hit2 may be potential candidates for CCR5 inhibition, and, therefore, can be considered for further CCR5 inhibition programs.


Asunto(s)
Inhibidores de Fusión de VIH , Infecciones por VIH , Humanos , Maraviroc/farmacología , VIH/metabolismo , Simulación del Acoplamiento Molecular , Cisteína , Infecciones por VIH/tratamiento farmacológico , Farmacóforo , Receptores de Quimiocina , Simulación de Dinámica Molecular , Receptores CCR5/metabolismo , Inhibidores de Fusión de VIH/farmacología , Inhibidores de Fusión de VIH/química
17.
Molecules ; 27(7)2022 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-35408569

RESUMEN

Considering the potential bioactivities of natural product and natural product-like compounds with highly complex and diverse structures, the screening of collections and small-molecule libraries for high-throughput screening (HTS) and high-content screening (HCS) has emerged as a powerful tool in the development of novel therapeutic agents. Herein, we review the recent advances in divergent synthetic approaches such as complexity-to-diversity (Ctd) and biomimetic strategies for the generation of structurally complex and diverse indole-based natural product and natural product-like small-molecule libraries.


Asunto(s)
Productos Biológicos , Indoles , Bibliotecas de Moléculas Pequeñas/química
18.
Molecules ; 27(4)2022 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-35209009

RESUMEN

Widely used in global households, fenugreek is well known for its culinary and medicinal uses. The various reported medicinal properties of fenugreek are by virtue of the different natural phytochemicals present in it. Regarded as a promising target, interleukin 2 receptor subunit alpha (IL2Rα) has been shown to influence immune responses. In the present research, using in silico techniques, we have demonstrated the potential IL2Rα binding properties of three polyphenol stilbenes (desoxyrhaponticin, rhaponticin, rhapontigenin) from fenugreek. As the first step, molecular docking was performed to assess the binding potential of the fenugreek phytochemicals with IL2Rα. All three phytochemicals demonstrated interactions with active site residues. To confirm the reliability of our molecular docking results, 100 ns molecular dynamics simulations studies were undertaken. As discerned by the RMSD and RMSF analyses, IL2Rα in complex with the desoxyrhaponticin, rhaponticin, and rhapontigenin indicated stability. The RMSD analysis of the phytochemicals alone also demonstrated no significant structural changes. Based on the stable molecular interactions and comparatively slightly better MM/PBSA binding free energy, rhaponticin seems promising. Additionally, ADMET analysis performed for the stilbenes indicated that all of them obey the ADMET rules. Our computational study thus supports further in vitro IL2Rα binding studies on these stilbenes, especially rhaponticin.


Asunto(s)
Subunidad alfa del Receptor de Interleucina-2/química , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Extractos Vegetales/química , Polifenoles/química , Estilbenos/química , Trigonella/química , Sitios de Unión , Fenómenos Químicos , Enlace de Hidrógeno , Subunidad alfa del Receptor de Interleucina-2/metabolismo , Estructura Molecular , Fitoquímicos/química , Extractos Vegetales/farmacología , Polifenoles/farmacología , Unión Proteica , Estilbenos/farmacología
19.
J Obstet Gynaecol ; 42(7): 3149-3157, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35929918

RESUMEN

Although ovarian cancer usually responds well to platinum- and taxane-based first-line chemotherapy, most patients develop recurrence and chemoresistance. Regenerating gene 4 (REG4) is a secretory protein involved in cell differentiation and proliferation. We found higher REG4 expression in ovarian cancer than in normal tissues (p < .05). Regenerating gene 4 expression was negatively associated with overall, progression-free or post-progression survival rates of patients with ovarian cancer receiving platinum or paclitaxel treatment (p < .05) according to a Kaplan-Meier plotter. Regenerating gene 4 overexpression resulted in either cisplatin or paclitaxel resistance, and apoptosis resistance in CAOV3 ovarian cancer cells (p < .05). REG4-transfected ovarian cancer cells showed stronger migration and invasion treated with cisplatin or paclitaxel (p < .05). Additionally, cisplatin or paclitaxel exposure led to the overexpression of phosphorylated phosphoinositide 3-kinase (p-PI3K), p-Akt, phosphorylated mammalian target of rapamycin (p-mTOR), glutathione S-transferase-π, survivin, and B-cell lymphoma 2 in REG4 transfectants compared with control cells (p < .05). These findings suggested that REG4 expression was up-regulated in ovarian cancer, and associated with poor survival and chemotherapy resistance. REG4 promoted the occurrence, development, and chemotherapy resistance of ovarian cancer by regulating cell proliferation, apoptosis, migration, and invasion, and PI3K/Akt/m-TOR signalling pathways. IMPACT STATEMENTWhat is already known on this subject? REG4 mRNA expression is up-regulated in many digestive cancers. High REG4 expression was associated with an adverse prognosis, high tumour and nodal stages, poor differentiation, and hepatic and peritoneal metastases of digestive cancers. REG4 expression conferred cancer cells with increased resistance to chemoradiotherapy, especially 5-FU-based treatment, by activating the MAPK/Erk/Bim signalling pathway.What do the results of this study add? REG4 was highly expressed in ovarian cancer. The expression of p-PI3K, p-AKT, p-mTOR, GST-π, survivin, and Bcl-2 was increased in REG4-overexpressing cells. High REG4 expression was significantly associated with inferior OS, PFS, and PPS rates in patients with ovarian cancer receiving platinum chemotherapy. REG4 mediated cisplatin and paclitaxel resistance in CAOV3 ovarian cancer cells. The percentage of apoptotic cells was markedly lower in REG4-transfected compared to mock-transfected cells after cisplatin or paclitaxel treatment.What are the implications of these findings for clinical practice and/or further research? This study aimed to evaluate the prognostic significance of REG4 expression in ovarian cancer treated with platinum and paclitaxel, to explore REG4 chemoresistance mechanisms to platinum and paclitaxel, and to provide a scientific experimental basis for the clinical treatment and outcome evaluation of ovarian cancer. In order to provide comprehensive clinical treatment of ovarian cancer, it is helpful to improve our understanding of multi-drug resistance and identify new cancer diagnostic biomarkers.


Asunto(s)
Cisplatino , Neoplasias Ováricas , Proteínas Asociadas a Pancreatitis , Femenino , Humanos , Apoptosis , Línea Celular Tumoral , Cisplatino/uso terapéutico , Resistencia a Antineoplásicos/genética , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/genética , Neoplasias Ováricas/patología , Paclitaxel , Proteínas Asociadas a Pancreatitis/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Platino (Metal)/farmacología , Platino (Metal)/uso terapéutico , Proteínas Proto-Oncogénicas c-akt/metabolismo , Survivin/metabolismo , Serina-Treonina Quinasas TOR/metabolismo
20.
Ann Surg ; 274(2): e150-e159, 2021 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-31436549

RESUMEN

BACKGROUND: Pathologic complete response (pCR) has been shown to be associated with favorable outcomes in breast cancer. Predictors of pCR could be useful in guiding treatment decisions regarding neoadjuvant therapy. The objective of this study was to evaluate cyclin E as a predictor of response to neoadjuvant chemotherapy in breast cancer. METHODS: Patients (n = 285) with stage II-III breast cancer were enrolled in a prospective study and received neoadjuvant chemotherapy with anthracyclines, taxanes, or combination of the two. Pretreatment biopsies from 190 patients and surgical specimens following chemotherapy from 192 patients were available for immunohistochemical analysis. Clinical and pathologic responses were recorded and associated with presence of tumor infiltrating lymphocytes, cyclin E, adipophilin, programmed cell death-ligand 1, and elastase staining and other patient, tumor and treatment characteristics. RESULTS: The pCR rate was significantly lower in patients with cytoplasmic cyclin E staining compared with those who had no cyclin E expression (16.1% vs 38.9%, P = 0.0005). In multivariable logistic regression analysis, the odds of pCR for patients who had cytoplasmic negative tumors was 9.35 times (P value < 0.0001) that compared with patients with cytoplasmic positive tumors after adjusting for ER, PR, and HER2 status. Cytoplasmic cyclin E expression also predicts long-term outcome and is associated with reduced disease free, recurrence free, and overall survival rates, independent of increased pretreatment tumor infiltrating lymphocytes. CONCLUSIONS: Cyclin E independently predicted response to neoadjuvant chemotherapy. Hence, its routine immunohistochemical analysis could be used clinically to identify those breast cancer patients expected to have a poor response to anthracycline/taxane-based chemotherapy.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Ciclina E/metabolismo , Adulto , Anciano , Antraciclinas/administración & dosificación , Biomarcadores de Tumor/metabolismo , Biopsia , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Quimioterapia Adyuvante , Femenino , Humanos , Persona de Mediana Edad , Terapia Neoadyuvante , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Estudios Prospectivos , Tasa de Supervivencia , Taxoides/administración & dosificación
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