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1.
Artigo em Inglês | MEDLINE | ID: mdl-38954823

RESUMO

Crohn's disease (CD) is an inflammatory bowel disease characterized by transmural inflammation and intestinal fibrosis. Mechanisms of fibrosis in CD are not well understood. Transmural inflammation is associated with inflammatory cell infiltration, stenosis, and distention, which present mechanical stress (MS) to the bowel wall. We hypothesize that MS induces gene expression of pro-fibrotic mediators such as connective tissue growth factor (CTGF), which may contribute to fibrosis in CD. A rodent model of CD was induced by intracolonic instillation of TNBS to the distal colon. TNBS instillation induced a localized transmural inflammation (site I), with a distended colon segment (site P) proximal to site I. We detected significant fibrosis and collagen content not only in site I, but also in site P in CD rats by day 7. CTGF expression increased significantly in sites P and I, but not in the segment distal to the inflammation site. Increased CTGF expression was detected mainly in the smooth muscle cells (SMC). When rats were fed exclusively with clear liquid diet to prevent mechanical distention in colitis, expression of CTGF in sites P and I was blocked. Direct stretch led to robust expression of CTGF in colonic SMC. Treatment of CD rats with anti-CTGF antibody FG-3149 reduced fibrosis and collagen content in both sites P and I and exhibited consistent trends towards normalizing expression of collagen mRNAs. In conclusion, our studies suggest that mechanical stress, by up-regulating pro-fibrotic mediators i.e. CTGF, may play a critical role in fibrosis in CD.

2.
Biochem Biophys Res Commun ; 722: 150152, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-38795452

RESUMO

MicroRNAs (miRNAs) can positively regulate gene expression through an unconventional RNA activation mechanism involving direct targeting 3' untranslated regions (UTRs). Our prior study found miR-93-5p activates mitogen-activated protein kinase kinase kinase 2 (MAP3K2) in hepatocellular carcinoma (HCC) via its 3'UTR. However, the underlying mechanism remains elusive. Here, we identified two candidate AU-rich element (ARE) motifs (ARE1 and ARE2) adjacent to the miR-93-5p binding site located within the MAP3K2 3'UTR using AREsite2. Luciferase reporter and translation assays validated that only ARE2 participated in MAP3K2 activation. Integrative analysis revealed that human antigen R (HuR), an ARE2-associated RNA-binding protein (RBP), physically and functionally interacted with the MAP3K2 3'UTR. Consequently, an HuR-ARE2 complex was shown to facilitate miR-93-5p-mediated upregulation of MAP3K2 expression. Furthermore, bioinformatics analysis and studies of HCC cells and specimens highlighted an oncogenic role for HuR and positive HuR-MAP3K2 expression correlation. HuR is also an enhancing factor in the positive feedback circuit comprising miR-93-5p, MAP3K2, and c-Jun demonstrated in our prior study. The newly identified HuR-ARE2 involvement enriches the mechanism of miR-93-5p-driven MAP3K2 activation and suggests new therapeutic strategies warranted for exploration in HCC.


Assuntos
Regiões 3' não Traduzidas , Carcinoma Hepatocelular , Proteína Semelhante a ELAV 1 , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas , MAP Quinase Quinase Quinase 2 , MicroRNAs , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Regiões 3' não Traduzidas/genética , MAP Quinase Quinase Quinase 2/metabolismo , MAP Quinase Quinase Quinase 2/genética , Proteína Semelhante a ELAV 1/metabolismo , Proteína Semelhante a ELAV 1/genética , Linhagem Celular Tumoral , Biossíntese de Proteínas
3.
Bioorg Chem ; 148: 107454, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38795581

RESUMO

HPK1 also referred to as MAP4K1, belongs to the category of mammalian STE20-like protein serine/threonine kinases. Its physiological function involves the down-regulation of T cell signals, and it is regarded as a new immune checkpoint of tumor immunology. In this study, we commenced our investigation with the hit compounds, focusing the efforts on structural optimization and SAR exploration to identify a novel class of 2,4-diaminopyrimidine HPK1 inhibitors. Notably, compound 14g exhibited a remarkable inhibitory effect on HPK1 kinase (IC50 = 0.15 nM), significantly suppressed the phosphorylation of the downstream adaptor protein SLP76 (pSLP76 IC50 = 27.92 nM), and effectively stimulated the secretion of the T cell activation marker IL-2 (EC50 = 46.64 nM). In vitro microsomal stability assay, compound 14g showed moderate stability in HLMs with T1/2 = 38.2 min and CLint = 36.4 µL·min-1·mg-1 proteins. In vivo pharmacokinetic studies, compound 14g demonstrated heightened plasma exposure (AUC0-inf = 644 ng·h·mL-1), extended half-life (T1/2 = 9.98 h), and reduced plasma clearance (CL = 52.3 mL·min-1·kg-1) compared to the reference compound after a single intravenous dose of 2 mg/kg in rats. These results indicated that compound 14g emerged as a promising inhibitor of HPK1.


Assuntos
Desenho de Fármacos , Inibidores de Proteínas Quinases , Proteínas Serina-Treonina Quinases , Pirimidinas , Pirimidinas/farmacologia , Pirimidinas/química , Pirimidinas/síntese química , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Humanos , Relação Estrutura-Atividade , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Estrutura Molecular , Ratos , Relação Dose-Resposta a Droga , Masculino , Simulação de Acoplamento Molecular , Ratos Sprague-Dawley
4.
Anesth Analg ; 138(2): 456-464, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37874765

RESUMO

BACKGROUND: Hypoxia often occurs due to shared airway and anesthetic sedation-induced hypoventilation in patients receiving flexible bronchoscopy (FB) under deep sedation. Previous evidence has shown that supraglottic jet oxygenation and ventilation (SJOV) via Wei nasal jet tube (WNJ) reduces the incidence of hypoxia during FB. This study aimed to investigate the extent to which SJOV via WNJ could decrease the incidence of hypoxia in patients under deep sedation as compared to oxygen supplementation via WNJ alone or nasal catheter (NC) for oxygen supplementation during FB. METHODS: This was a single-center 3-arm randomized controlled trial (RCT). Adult patients scheduled to undergo FB were randomly assigned to 3 groups: NC (oxygen supplementation via NC), low-pressure low-flow (LPLF) (low-pressure oxygen supplementation via WNJ alone), or SJOV (high-pressure oxygen supplementation via WNJ). The primary outcome was hypoxia (defined as peripheral saturation of oxygen [Sp o2 ] <90% lasting more than 5 seconds) during FB. Secondary outcomes included subclinical respiratory depression or severe hypoxia, and rescue interventions specifically performed for hypoxia treatment. Other evaluated outcomes were sore throat, xerostomia, nasal bleeding, and SJOV-related barotraumatic events. RESULTS: One hundred and thirty-two randomized patients were included in 3 interventions (n = 44 in each), and all were included in the final analysis under intention to treat. Hypoxia occurred in 4 of 44 patients (9.1%) allocated to SJOV, compared to 38 of 44 patients (86%) allocated to NC, with a relative risk (RR) for hypoxia, 0.11; 98% confidence interval (CI), 0.02-0.51; P < .001; or to 27 of 44 patients (61%) allocated to LPLF, with RR for hypoxia, 0.15; 95% CI, 0.04-0.61; P < .001, respectively. The percentage of subclinical respiratory depression was also significantly diminished in patients with SJOV (39%) compared with patients with NC (100%) or patients with LPLF (96%), both P < .001. In SJOV, no severe hypoxia event occurred. More remedial interventions for hypoxia were needed in the patients with NC. Higher risk of xerostomia was observed in patients with SJOV. No severe adverse event was observed throughout the study. CONCLUSIONS: SJOV via WNJ effectively reduces the incidence of hypoxia during FB under deep sedation.


Assuntos
Sedação Profunda , Insuficiência Respiratória , Xerostomia , Adulto , Humanos , Broncoscopia/efeitos adversos , Sedação Profunda/efeitos adversos , Hipóxia/diagnóstico , Hipóxia/etiologia , Hipóxia/prevenção & controle , Oxigênio , Xerostomia/complicações
5.
Graefes Arch Clin Exp Ophthalmol ; 262(5): 1409-1419, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37815595

RESUMO

PURPOSE: To compare the efficacy of different anti-vascular endothelial growth factor (VEGF) agents for the treatment of retinopathy of prematurity (ROP) in preterm infants. METHODS: Seven databases were searched for eligible literature up to February 22, 2023. Studies were included if they were randomised controlled trials (RCTs) investigating the efficacy of anti-VEGF agents for ROP in infants. A network meta-analysis (NMA) was performed. We also conducted subgroup analyses to determine the efficacy ranking of regimens used in different regions. The odds ratio (OR), standardised mean difference (SMD), and surface under the cumulative ranking curve (SUCRA) were calculated for each outcome. RESULTS: Thirteen RCTs of 10 different regimens, involving 1196 infants (2388 eyes), were identified. Bevacizumab (0.625 mg; OR = 0.16, 95% confidence interval [CI] 0.06-0.40, SUCRA = 80.6%) and conbercept (0.15 mg; OR = 0.08, 95% CI 0.02-0.30, SUCRA = 96.0%) were the most effective regimens in reducing the risk of ROP recurrence requiring retreatment in Western countries and China, respectively. Compared with laser therapy, bevacizumab (0.625 mg; SMD = 1.54, 95% CI 0.06-3.02) achieved significantly longer intervals between treatment and recurrence. No significant difference in the risk of retinal detachment was detected between any anti-VEGF agent and laser (p > 0.05). CONCLUSIONS: Bevacizumab (0.625 mg) and conbercept (0.15 mg) appeared to be the most effective therapies for ROP in Western countries and China, respectively. More high-quality RCTs are warranted to evaluate the efficacy and long-term safety of anti-VEGF drugs for the management of ROP.

6.
Molecules ; 29(3)2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38338416

RESUMO

Protein tyrosine phosphatases (PTPs) are ubiquitous in living organisms and are promising drug targets for cancer, diabetes/obesity, and autoimmune disorders. In this study, a histone deacetylase inhibitor called suberoylanilide hydroxamic acid (SAHA) was added to a culture of marine fungi (Aspergillus sydowii DL1045) to identify potential drug candidates related to PTP inhibition. Then, the profile of the induced metabolites was characterized using an integrated metabolomics strategy. In total, 46% of the total SMs were regulated secondary metabolites (SMs), among which 20 newly biosynthesized metabolites (10% of the total SMs) were identified only in chemical epigenetic regulation (CER) broth. One was identified as a novel compound, and fourteen compounds were identified from Aspergillus sydowii first. SAHA derivatives were also biotransformed by A. sydowii DL1045, and five of these derivatives were identified. Based on the bioassay, some of the newly synthesized metabolites exhibited inhibitory effects on PTPs. The novel compound sydowimide A (A11) inhibited Src homology region 2 domain-containing phosphatase-1 (SHP1), T-cell protein tyrosine phosphatase (TCPTP) and leukocyte common antigen (CD45), with IC50 values of 1.5, 2.4 and 18.83 µM, respectively. Diorcinol (A3) displayed the strongest inhibitory effect on SHP1, with an IC50 value of 0.96 µM. The structure-activity relationship analysis and docking studies of A3 analogs indicated that the substitution of the carboxyl group reduced the activity of A3. Research has demonstrated that CER positively impacts changes in the secondary metabolic patterns of A. sydowii DL1045. The compounds produced through this approach will provide valuable insights for the creation and advancement of novel drug candidates related to PTP inhibition.


Assuntos
Aspergillus , Epigênese Genética , Aspergillus/química , Proteínas Tirosina Fosfatases , Vorinostat/farmacologia
7.
Environ Monit Assess ; 196(3): 307, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38407658

RESUMO

As the initial stage of the sewage treatment system, the degradation of pollutants inevitably involves an entropy change process. Microorganisms play a vital role, where they interact with pollutants and constantly adjust own ecosystem. However, there is a lack of research on the entropy change and external dissipation processes within the sewer system. In this study, considering the characteristics of microbial population changes in the biofilm within the urban sewage pipe network, entropy theory is applied to characterize the attributes of different microorganisms. Through revealing the entropy change of the microbial population and chemical composition, a coupling relationship between the functional bacteria diversity, organic substances composition, and external dissipation in the pipeline network is proposed. The results show that the changes of nutrient availability, microbial community structure, and environmental conditions all affect the changes of information entropy in the sewer network. This study is critical for assessing the understanding of ecological dynamics and energy flows within these systems and can help researchers and operation managers develop strategies to optimize wastewater treatment processes, mitigate environmental impacts, and promote sustainable management practices.


Assuntos
Ecossistema , Poluentes Ambientais , Entropia , Esgotos , Monitoramento Ambiental
8.
Angew Chem Int Ed Engl ; : e202410815, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38925600

RESUMO

Small-molecule receptors are increasingly employed to probe various functional groups for (bio)chemical analysis. However, differentiation of polyfunctional analogs sharing multiple functional groups remains challenging for conventional mono- and bidentate receptors because their insufficient number of binding sites limits interactions with the least reactive yet property-determining functional group. Herein, we introduce 6-thioguanine (TG) as a supramolecular receptor for unique tridentate receptor-analyte complexation,achieving ≥ 95% identification accuracy among 16 polyfunctional analogs across three scenarios: glycerol derivatives, disubstituted propanes, and vicinal diols. Crucially, we demonstrate distinct spectral changes induced by the tridentate interaction between TG's three anchoring points and all the analyte's functional groups, even the least reactive ones. Notably, H-bond networks formed in the TG-analyte complexes demonstrate additive effect in binding strength originating from good bond linearity, cooperativity, and resonance, thus strengthens complexation events and amplifies the differences in spectral changes induced among analytes. It also enhances spectral consistency by selectively form a sole configuration that is stronger than the respective analyte-analyte interaction. Finally, we achieve 95.4% accuracy for multiplex identification of a mixture consisting of multiple polyfunctional analogs. We envisage that extension to other multidentate non-covalent interactions enables the development of interference-free small molecule-based sensors for various (bio)chemical analysis applications.

9.
Small ; 19(39): e2300703, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37283473

RESUMO

Photothermal steam generation promises decentralized water purification, but current methods suffer from slow water evaporation even at high photothermal efficiency of ≈98%. This drawback arises from the high latent heat of vaporization that is required to overcome the strong and extensive hydrogen bonding network in water for steam generation. Here, light-to-vapor conversion is boosted by incorporating chaotropic/kosmotropic chemistries onto plasmonic nanoheater to manipulate water intermolecular network at the point-of-heating. The chaotropic-plasmonic nanoheater affords rapid light-to-vapor conversion (2.79 kg m-2  h-1  kW-1 ) at ≈83% efficiency, with the steam generation rate up to 6-fold better than kosmotropic platforms or emerging photothermal designs. Notably, the chaotropic-plasmonic nanoheater also lowers the enthalpy of water vaporization by 1.6-fold when compared to bulk water, signifying that a correspondingly higher amount of steam can be generated with the same energy input. Simulation studies unveil chaotropic surface chemistry is crucial to disrupt water hydrogen bonding network and suppress the energy barrier for water evaporation. Using the chaotropic-plasmonic nanoheater, organic-polluted water is purified at ≈100% efficiency, a feat otherwise challenging in conventional treatments. This study offers a unique chemistry approach to boost light-driven steam generation beyond a material photothermal property.

10.
Microb Ecol ; 85(4): 1288-1299, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35522265

RESUMO

Microbial co-culture simulates the natural ecosystem through the combination of artificial microbes. This approach has been widely applied in the study of activating silent genes to reveal novel secondary metabolites. However, there are still challenges in determining the biosynthetic pathways. In this study, the effects of microbial co-culture on the morphology of the microbes were verified by the morphological observation. Subsequently, through the strategy combining substrate feeding, stable isotope labeling, and gene expression analysis, the biosynthetic pathways of five benzoic acid derivatives N1-N4 and N7 were demonstrated: the secondary metabolite 10-deoxygerfelin of A. sydowii acted as an inducer to induce B. subtilis to produce benzoic acid, which was further converted into 3-OH-benzoic acid by A. sydowii. Subsequently, A. sydowii used 3-OH-benzoic acid as the substrate to synthesize the new compound N2, and then N1, N3, N4, and N7 were biosynthesized upon the upregulation of hydrolase, hydroxylase, and acyltransferase during co-culture. The plate zone analysis suggested that the biosynthesis of the newly induced compounds N1-N4 was mainly attributed to A. sydowii, and both A. sydowii and B. subtilis were indispensable for the biosynthesis of N7. This study provides an important basis for a better understanding of the interactions among microorganisms, providing new ideas for studying the biosynthetic pathways of the newly induced secondary metabolites in co-culture.


Assuntos
Bacillus subtilis , Ecossistema , Bacillus subtilis/genética , Técnicas de Cocultura , Ácido Benzoico
11.
Cost Eff Resour Alloc ; 21(1): 65, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37705023

RESUMO

BACKGROUND: The aim of the study was to evaluate the cost-effectiveness of nivolumab plus chemotherapy as first-line treatment for patients with advanced gastric, gastroesophageal junction (GEJ), or esophageal adenocarcinoma from the perspective of Chinese and US society. METHODS: To conduct the analysis, a state-transitioned Markov model, which included three mutually exclusive health states (progression-free survival (PFS), progressive disease (PD), and death), was developed. Cycle length was set at 3 weeks and lifetime horizon was set at 10 years. Costs, quality-adjusted life years (QALYs), and incremental cost-effectiveness ratio (ICER) were calculated in the analysis. Willingness-to-pay (WTP) thresholds in the model were set at $37,653.00/QALY in China and $100,000.00/QALY in the US, respectively. Meanwhile, one-way sensitivity analyses and probabilistic sensitivity analyses were conducted to investigate the robustness of the model. RESULTS: Over a lifetime horizon, the ICERs of nivolumab plus chemotherapy versus chemotherapy alone were $430,185.04/QALY and $944,089.78/QALY in China and the US, respectively. Cost of nivolumab and utility for the PFS state had the most significant impact on ICERs both in the US and China based on the results of the one-way sensitivity analyses. In the probabilistic sensitivity analyses, the proportions of nivolumab plus chemotherapy being cost-effective compared with chemotherapy alone were 0%. CONCLUSIONS: In conclusion, nivolumab plus chemotherapy is unlikely to be a cost-effective treatment option compared with chemotherapy alone in the first-line setting of advanced gastric, GEJ, or esophageal adenocarcinoma.

12.
Bioorg Chem ; 134: 106442, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36878064

RESUMO

Dual inhibitors of JAK2 and FLT3 can synergistically control the development of acute myeloid leukemia (AML), and overcome secondary drug resistance of AML that is associated with FLT3 inhibition. We therefore designed and synthesized a series of 4-piperazinyl-2-aminopyrimidines as dual inhibitors of JAK2 and FLT3, and improved their selectivity for JAK2. Screening cascades revealed that compound 11r exhibited inhibitory activity with IC50 values of 2.01, 0.51, and 104.40 nM against JAK2, FLT3, and JAK3, respectively. Compound 11r achieved a high selectivity for JAK2 at a ratio of 51.94, and also showed potent antiproliferative activity in HEL (IC50 = 1.10 µM) and MV4-11 (IC50 = 9.43 nM) cell lines. In an in vitro metabolism assay, 11r exhibited moderate stability in human liver microsomes (HLMs), with a half-life time of 44.4 min, and in rat liver microsomes (RLMs), with a half-life of 143 min. In pharmacokinetic studies, compound 11r showed moderate absorption (Tmax = 5.33 h), with a peak concentration of 38.7 ng/mL and an AUC of 522 ng h/mL in rats, and an oral bioavailability of 25.2%. In addition, 11r induced MV4-11 cell apoptosis in a dose-dependent manner. These results indicate that 11r is a promising selective JAK2/FLT3 dual inhibitor.


Assuntos
Antineoplásicos , Leucemia Mieloide Aguda , Ratos , Humanos , Animais , Relação Estrutura-Atividade , Linhagem Celular Tumoral , Inibidores de Proteínas Quinases/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Microssomos Hepáticos/metabolismo , Apoptose , Tirosina Quinase 3 Semelhante a fms/metabolismo , Proliferação de Células , Antineoplásicos/uso terapêutico , Janus Quinase 2/metabolismo
13.
Int J Mol Sci ; 24(22)2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-38003513

RESUMO

The Hawaiian Islands are renowned for their exceptional biodiversity and are host to a plethora of endemic plant species, which have been utilized in traditional Hawaiian medicine. This scientific review provides an in-depth analysis of the phytochemistry and biological studies of selected endemic Hawaiian plants, highlighting their medicinal properties and therapeutic potential. A literature search was conducted, utilizing major academic databases such as SciFinder, Scopus, Web of Science, PubMed, Google Scholar, Science Direct, and the Scientific Information Database. The primary objective of this search was to identify relevant scholarly articles pertaining to the topic of the review, which focused on the phytochemistry and biological studies of endemic Hawaiian plants. Utilizing these databases, a comprehensive range of literature was obtained, facilitating a comprehensive examination of the subject matter. This review emphasizes the rich phytochemical diversity and biological activities found in Endemic Hawaiian plants, showcasing their potential as sources of novel therapeutic agents. Given the unique biodiversity of Hawaii and the cultural significance of these plants, continued scientific exploration, conservation, and sustainable utilization of these valuable resources is necessary to unlock the full potential of these plant species in drug discovery and natural product-based therapeutics.


Assuntos
Plantas Medicinais , Plantas Medicinais/química , Etnofarmacologia , Fitoterapia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Extratos Vegetais/química , Havaí , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/uso terapêutico , Compostos Fitoquímicos/química
14.
Angew Chem Int Ed Engl ; 62(44): e202309610, 2023 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-37675645

RESUMO

Molecular recognition of complex isomeric biomolecules remains challenging in surface-enhanced Raman scattering (SERS) spectroscopy due to their small Raman cross-sections and/or poor surface affinities. To date, the use of molecular probes has achieved excellent molecular sensitivities but still suffers from poor spectral specificity. Here, we induce "charge and geometry complementarity" between probe and analyte as a key strategy to achieve high spectral specificity for effective SERS molecular recognition of structural analogues. We employ 4-mercaptopyridine (MPY) as the probe, and chondroitin sulfate (CS) disaccharides with isomeric sulfation patterns as our proof-of-concept study. Our experimental and in silico studies reveal that "charge and geometry complementarity" between MPY's binding pocket and the CS sulfation patterns drives the formation of site-specific, multidentate interactions at the respective CS isomerism sites, which "locks" each CS in its analogue-specific complex geometry, akin to molecular docking events. Leveraging the resultant spectral fingerprints, we achieve > 97 % classification accuracy for 4 CSs and 5 potential structural interferences, as well as attain multiplex CS quantification with < 3 % prediction error. These insights could enable practical SERS differentiation of biologically important isomers to meet the burgeoning demand for fast-responding applications across various fields such as biodiagnostics, food and environmental surveillance.


Assuntos
Sondas Moleculares , Análise Espectral Raman , Análise Espectral Raman/métodos , Simulação de Acoplamento Molecular
15.
Mol Biol Evol ; 38(8): 3332-3344, 2021 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-33871608

RESUMO

The relationships among the four major embryophyte lineages (mosses, liverworts, hornworts, vascular plants) and the timing of the origin of land plants are enigmatic problems in plant evolution. Here, we resolve the monophyly of bryophytes by improving taxon sampling of hornworts and eliminating the effect of synonymous substitutions. We then estimate the divergence time of crown embryophytes based on three fossil calibration strategies, and reveal that maximum calibration constraints have a major effect on estimating the time of origin of land plants. Moreover, comparison of priors and posteriors provides a guide for evaluating the optimal calibration strategy. By considering the reliability of fossil calibrations and the influences of molecular data, we estimate that land plants originated in the Precambrian (980-682 Ma), much older than widely recognized. Our study highlights the important contribution of molecular data when faced with contentious fossil evidence, and that fossil calibrations used in estimating the timescale of plant evolution require critical scrutiny.


Assuntos
Anthocerotophyta/genética , Briófitas/genética , Fósseis , Genoma de Planta , Filogenia
16.
Hum Reprod ; 37(12): 2856-2866, 2022 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-36223608

RESUMO

STUDY QUESTION: Would the construction of a competing endogenous RNA (ceRNA) network help identify new drug targets for the development of potential therapies for polycystic ovary syndrome (PCOS)? SUMMARY ANSWER: Both Food and Drug Administartion (FDA)-approved and candidate drugs could be identified by combining bioinformatics approaches with clinical sample analysis based on our established ceRNA network. WHAT IS KNOWN ALREADY: Thus far, no effective drugs are available for treating PCOS. ceRNAs play crucial roles in multiple diseases, and some of them are in current use as prognostic biomarkers as well as for chemo-response and drug prediction. STUDY DESIGN, SIZE, DURATION: For the bioinformatics part, five microarrays of human granulosa cells were considered eligible after applying strict screening criteria and were used to construct the ceRNA network for target identification. For population-based validation, samples from 24 women with and without PCOS were collected from January 2021 to July 2021. PARTICIPANTS/MATERIALS, SETTING, METHODS: The public data included 27 unaffected women and 25 women with PCOS, according to the Rotterdam criteria proposed in 2003. The limma and RobustRankAggreg R packages were used to identify differentially expressed messenger RNAs and noncoding RNAs. Gene Ontology, Reactome and Kyoto Encyclopedia of Genes and Gemomes (KEGG) enrichment analyses were performed. A ceRNA network was constructed by integrating the differentially expressed genes and target genes. The population-based validation included human luteinized granulosa cell samples from 12 unaffected women and 12 women with PCOS. Quantitative real-time polymerase chain reaction was conducted to detect the levels of mRNAs and microRNAs (miRNAs). Connectivity map and computational model algorithms were implemented to predict therapeutic drugs from the ceRNA network. Additionally, we compared the predicted drugs with known clinical medications in DrugBank. MAIN RESULTS AND THE ROLE OF CHANCE: A set of 10 mRNAs, 11 miRNAs and 53 long non-coding RNAs (lncRNAs) were differentially expressed. Functional enrichment analysis revealed the highest relevance to immune system-related biological processes and signalling pathways, such as cytokine secretion and leucocyte chemotaxis. A ceRNA consisting of two lncRNAs, two miRNAs and five mRNAs was constructed. Through network construction via bioinformatic analysis, we identified some already approved drugs (such as metformin) that could target some molecules in the network as potential drug candidates for PCOS. LARGE SCALE DATA: Public sequencing data were obtained from GSE34526, GSE84376, GSE102293, GSE106724 and GSE114419, which have been deposited in the Gene Expression Omnibus database. LIMITATIONS, REASONS FOR CAUTION: Experiments, such as immunoprecipitation, luciferase reporter assays and animal model studies, are needed to validate the potential targets in the ceRNA network before the identified drug candidates can be tested using cellular and animal model systems. WIDER IMPLICATIONS OF THE FINDINGS: Our findings provide new bioinformatic insight into the possible pathogenesis of PCOS from ceRNA network analysis, which has not been previously studied in the human reproductive field. Our study also reveals some potential drug candidates for the future development of possible therapies against PCOS. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by grants from the National Key Research and Development Program of China (2021YFC2700400) and the National Natural Science Foundation of China (82001498). The authors have no conflicts of interest to disclose.


Assuntos
MicroRNAs , Síndrome do Ovário Policístico , RNA Longo não Codificante , Animais , Humanos , Feminino , RNA Longo não Codificante/genética , Síndrome do Ovário Policístico/tratamento farmacológico , Síndrome do Ovário Policístico/genética , Síndrome do Ovário Policístico/patologia , Redes Reguladoras de Genes , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
17.
Phys Chem Chem Phys ; 24(36): 22007-22015, 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36069513

RESUMO

van der Waals (vdW) heterostructures based on two-dimensional (2D) ferromagnetic materials hold great potential applications in spintronics. Using the density functional theory (DFT) method and first-principles quantum transport simulation, we studied the structures, magnetic properties and spin-resolved transport of 1T-CrO2 monolayer (ML) based vdW magnetic tunnel junctions (MTJs). Owing to a high Curie temperature (TC) of 392 K and a moderate magnetic anisotropy energy (MAE) of 94 µeV of the ferromagnetic 1T-CrO2 monolayer, Cu(111)|CrO2|nML-Gr|CrO2|Cu(111) MTJs were built. Our results reveal that their tunneling magnetoresistance (TMR) ratios are dependent on the number of Gr barrier layers within a working bias voltage of 1 V. For the thin barrier layers (n = 1-2), the maintained TMR ratios can reach a giant value of about 1 × 104%, while there appears a decreasing trend with the increasing bias voltage for thick Gr layers (n = 3-5). The barrier-layer-dependent phenomenon is attributed to the decreasing transmission magnitude with increasing bias voltage in a parallel configuration (PC), which is as small as that in an anti-parallel configuration (APC) eventually. Our results would provide some guidance for future experimental fabrications of these 2D materials based MTJs.

18.
Appl Microbiol Biotechnol ; 106(17): 5349-5358, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35882675

RESUMO

According to the United Nations population profile, the number of individuals aged 60 and over in high-income nations is expected to rise from 302 million to over 366 million between 2019 and 2030, so there is an increasing emphasis on nutrition and health in older people. Numerous studies have demonstrated the crucial role that gut microbiota plays in maintaining human health. As a model of healthy aging, centenarians have different gut microbiota from ordinary elderly people. The core microbiome of centenarians in various countries has shown some common characteristics, which are worth further exploration. In this review, the significance of the human gut microbiota to health is briefly discussed, and the characteristics of the gut microbiota of long-lived senior persons of different ages and in different countries are described. Moreover, this review lists dietary interventions and fecal microbiota transplantation. In the end, it discusses the pros and cons of using probiotics to enhance the health of seniors through focused management of the gut microbiota. It aims to pave the way for further investigation into the nexus between gut microbiota, probiotics, and longevity, and then to reveal the underlying mechanism to promote longevity. KEY POINTS: • Gut microbial structure in different age groups and the characteristics of gut microbiota in centenarians. • Dietary interventions, fecal transplants, and probiotics target the modulation of gut microbiota for healthy aging.


Assuntos
Microbioma Gastrointestinal , Probióticos , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Transplante de Microbiota Fecal , Humanos , Longevidade , Pessoa de Meia-Idade
19.
Anim Genet ; 53(3): 317-326, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35292981

RESUMO

The melanocortin 1 receptor (MC1R), encoded by the classical extension (E) coat color locus, is expressed on the surface of melanocytes and plays a critical role in switching melanin synthesis from pheomelanin (red/yellow) to eumelanin (black/brown). Different MC1R alleles associated with various coat color patterns in pigs have been identified over the past decades. However, functional analysis of variant porcine MC1R alleles has not yet been performed. Therefore, in this study, we examined the subcellular localization and cyclic adenosine monophosphate (cAMP) signaling capability of MC1R variants in porcine kidney epithelial cells (PK15) overexpressing different MC1R alleles. Transcriptional slippage may partially restore the reading frame of the EP allele, possibly accounting for the observed spot phenotype. The A243T substitution in the e allele severely disrupted the membrane localization of the MC1R receptor, resulting in a severely impaired cAMP signaling capability. Both the V95M and L102P substitutions in the ED1 allele may contribute to the constitutively active function of MC1R, thus accounting for the dominant black phenotype. The D124N substitution in the ED2 allele severely attenuated the cAMP signaling capability of MC1R; however, whether this mutation contributes to the distinct phenotype of Hampshire pigs requires further investigation. Thus, our results provide new insights into the functional characteristics of MC1R variants and their roles in porcine coat color formation.


Assuntos
Mutação de Sentido Incorreto , Receptor Tipo 1 de Melanocortina , Alelos , Animais , Cor de Cabelo , Mutação , Fenótipo , Receptor Tipo 1 de Melanocortina/genética , Suínos/genética
20.
Molecules ; 28(1)2022 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-36615412

RESUMO

Chemical epigenetic regulation (CER) is an effective method to activate the silent pathway of fungal secondary metabolite synthesis. However, conventional methods for CER study are laborious and time-consuming. In the meantime, the overall profile of the secondary metabolites in the fungi treated by the CER reagent is not well characterized. In this study, suberohydroxamic acid (SBHA), a histone deacetylase inhibitor, was added to a culture of Aspergillus aculeatus DL1011 and a new strategy based on LC-MS/MS analysis integrated with various metabolomic tools (MetaboAnalyst, MS-DIAL, SIRIUS and GNPS) was developed to characterize the profile of induced metabolites. As a result, 13.6%, 29.5% and 27.2% of metabolites were identified as newly biosynthesized, increasing and decreasing in abundance by CER, respectively. The structures of the 18 newly induced secondary metabolites were further identified by the new strategy to demonstrate that 72.2% of them (1 novel compound and 12 known compounds) were first discovered in A. aculeatus upon SBHA treatment. The accuracy of the new approach was confirmed by purification and NMR data analysis of major newly biosynthesized secondary metabolites. The bioassay showed that the newly biosynthesized compounds, roseopurpurin analogues, showed selective activities against DPPH scavenging, cytotoxicity and SHP1 inhibition. Our research demonstrated that CER was beneficial for changing the secondary metabolic profile of fungi and was an effective means of increasing the diversity of active metabolites. Our work also supplied a metabolomic strategy to characterize the profile changes and determine the newly induced compounds in the secondary metabolites of fungi treated with the chemical epigenetic regulator.


Assuntos
Epigênese Genética , Espectrometria de Massas em Tandem , Cromatografia Líquida , Aspergillus/química , Metabolismo Secundário
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