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1.
Front Physiol ; 15: 1405569, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38983721

RESUMO

Histone deacetylases (HDAC) catalyze the removal of acetylation modifications on histones and non-histone proteins, which regulates gene expression and other cellular processes. HDAC inhibitors (HDACi), approved anti-cancer agents, emerge as a potential new therapy for heart diseases. Cardioprotective effects of HDACi are observed in many preclinical animal models of heart diseases. Genetic mouse models have been developed to understand the role of each HDAC in cardiac functions. Some of the findings are controversial. Here, we provide an overview of how HDACi and HDAC impact cardiac functions under physiological or pathological conditions. We focus on in vivo studies of zinc-dependent classical HDACs, emphasizing disease conditions involving cardiac hypertrophy, myocardial infarction (MI), ischemic reperfusion (I/R) injury, and heart failure. In particular, we review how non-biased omics studies can help our understanding of the mechanisms underlying the cardiac effects of HDACi and HDAC.

2.
Nanomaterials (Basel) ; 14(13)2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38998675

RESUMO

Conventional coalbed methane (CBM) reservoir models for injection fall-off testing often disregard the quadratic pressure gradient's impact. This omission leads to discrepancies in simulating the transient behavior of formation fluids and extracting critical reservoir properties. Accurate determination of permeability, storability, and other properties is crucial for effective reservoir characterization and production forecasting. Inaccurate estimations can lead to suboptimal well placement, ineffective production strategies, and ultimately, missed economic opportunities. To address this shortcoming, we present a novel analytical model that explicitly incorporates the complexities of the quadratic pressure gradient and dual-permeability flow mechanisms, prevalent in many CBM formations where nanopores are rich, presenting a kind of natural nanomaterial. This model offers significant advantages over traditional approaches. By leveraging variable substitution, it facilitates the derivation of analytical solutions in the Laplace domain, subsequently converted to real-space solutions for practical application. These solutions empower reservoir engineers to generate novel type curves, a valuable tool for analyzing wellbore pressure responses during injection fall-off tests. By identifying distinct flow regimes within the reservoir based on these type curves, engineers gain valuable insights into the dynamic behavior of formation fluids. This model goes beyond traditional approaches by investigating the influence of the quadratic pressure gradient coefficient, inter-porosity flow coefficient, and storability ratio on the pressure response. A quantitative comparison with traditional models further elucidates the key discrepancies caused by neglecting the quadratic pressure gradient. The results demonstrate the proposed model's ability to accurately depict the non-linear flow behavior observed in CBM wells. This translates to more reliable pressure and pressure derivative curves that account for the impact of the quadratic pressure gradient.

3.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(7): 690-694, 2024 Jul 15.
Artigo em Chinês | MEDLINE | ID: mdl-39014944

RESUMO

OBJECTIVES: To investigate the application of endoscopic retrograde cholangiopancreatography (ERCP) in children and the risk factors for post-ERCP pancreatitis (PEP). METHODS: A retrospective analysis was conducted on the clinical data of 66 children, aged ≤16 years, who underwent ERCP for pancreaticobiliary diseases at the Gastrointestinal Endoscopy Center of the Second Affiliated Hospital of Kunming Medical University from September 2013 to September 2023. The incidence rate of PEP and the risk factors for the development of PEP were analyzed. RESULTS: A total of 78 ERCP procedures were performed on 66 children, with 5 diagnostic ERCPs, 69 therapeutic ERCPs, and 4 failed procedures. The success rate of ERCP operations was 95% (74/78). There were 17 cases of PEP in total, with an incidence rate of 22%. In the PEP group, the proportion of children with normal preoperative bilirubin and the proportion of guidewire insertion into the pancreatic duct during surgery were higher than in the non-PEP group (P<0.05). The multivariate logistic regression analysis showed that guidewire insertion into the pancreatic duct was an independent risk factor for PEP (P<0.05). CONCLUSIONS: With the increasing application of ERCP in children with pancreaticobiliary diseases, it is important to select an appropriate intubation technique during surgery to avoid blindly entering the guidewire into the pancreatic duct and reduce the occurrence of PEP.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica , Pancreatite , Humanos , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Criança , Masculino , Pancreatite/etiologia , Pancreatite/prevenção & controle , Feminino , Fatores de Risco , Estudos Retrospectivos , Pré-Escolar , Adolescente , Modelos Logísticos , Lactente
4.
Artigo em Inglês | MEDLINE | ID: mdl-38988166

RESUMO

BACKGROUND: With conventional cancer treatments facing limitations, interest in plant-derived natural products as potential alternatives is increasing. Although resveratrol has demonstrated antitumor effects in various cancers, its impact and mechanism on nasopharyngeal carcinoma remain unclear. OBJECTIVE: This study aimed to systematically investigate the anti-cancer effects of resveratrol on nasopharyngeal carcinoma using a combination of experimental pharmacology, network pharmacology, and molecular docking approaches. METHODS: CCK-8, scratch wound, and transwell assays were employed to confirm the inhibitory effect of resveratrol on the proliferation, migration, and invasion of nasopharyngeal carcinoma cells. H&E and TUNEL stainings were used to observe the morphological changes and apoptosis status of resveratrol-treated cells. The underlying mechanisms were elucidated using a network pharmacology approach. Immunohistochemistry and Western blotting were utilized to validate key signaling pathways. RESULTS: Resveratrol inhibited the proliferation, invasion, and migration of nasopharyngeal carcinoma cells, ultimately inducing apoptosis in a time- and dose-dependent manner. Network pharmacology analysis revealed that resveratrol may exert its anti-nasopharyngeal carcinoma effect mainly through the MAPK pathway. Immunohistochemistry results from clinical cases showed MAPK signaling activation in nasopharyngeal carcinoma tissues compared to adjacent tissues. Western blotting validated the targeting effect of resveratrol, demonstrating significant inhibition of the MAPK signaling pathway. Furthermore, molecular docking supported its multi-target role with MAPK, TP53, PIK3CA, SRC, etc. Conclusion: Resveratrol has shown promising potential in inhibiting human nasopharyngeal carcinoma cells by primarily targeting the MAPK pathway. These findings position resveratrol as a potential therapeutic agent for nasopharyngeal carcinoma.

5.
Viruses ; 16(6)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38932283

RESUMO

Since it was first reported in 2013, the NADC30-like PRRSV has been epidemic in China. Hubei Province is known as China's key hog-exporting region. To understand the prevalence and genetic variation of PRRSV, herein, we detected and analyzed 317 lung tissue samples from pigs with respiratory disease in Hubei Province, and demonstrated that the NADC30-like strain was the second-most predominant strain during 2017-2018, following the highly pathogenic PRRSV (HP-PRRSV). Additionally, we isolated a new NADC30-like PRRSV strain, named CHN-HB-2018, which could be stably passaged in Marc-145 cells. Genetic characterization analysis showed that compared with the NADC30 strain, the CHN-HB-2018 strain had several amino acid variations in glycoprotein (GP) 3, GP5, and nonstructural protein 2 (NSP2). Moreover, the CHN-HB-2018 strain showed a unique 5-amino acid (aa) deletion in NSP2, which has not previously been reported. Gene recombination analysis identified the CHN-HB-2018 strain as a potentially recombinant PRRSV of the NADC30-like strain and HP-PRRSV. Animal experiments indicated that the CHN-HB-2018 strain has a mild pathogenicity, with no mortality and only mild fever observed in piglets. This study contributes to defining the evolutionary characteristics of PRRSV and its molecular epidemiology in Hubei Province, and provides a potential candidate strain for PRRSV vaccine development.


Assuntos
Filogenia , Síndrome Respiratória e Reprodutiva Suína , Vírus da Síndrome Respiratória e Reprodutiva Suína , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Vírus da Síndrome Respiratória e Reprodutiva Suína/patogenicidade , Vírus da Síndrome Respiratória e Reprodutiva Suína/classificação , Animais , Suínos , Síndrome Respiratória e Reprodutiva Suína/virologia , Síndrome Respiratória e Reprodutiva Suína/epidemiologia , China/epidemiologia , Virulência , Genoma Viral , Recombinação Genética , Variação Genética , Pulmão/virologia , Pulmão/patologia
6.
Artigo em Inglês | MEDLINE | ID: mdl-38864709

RESUMO

Dysregulation of α cells results in hyperglycemia and hyperglucagonemia in type 2 diabetes mellitus (T2DM). Mesenchymal stromal cell (MSC)-based therapy increases oxygen consumption of islets and enhances insulin secretion. However, the underlying mechanism for the protective role of MSCs in α-cell mitochondrial dysfunction remains unclear. Here, human umbilical cord MSCs (hucMSCs) were used to treat 2 kinds of T2DM mice and αTC1-6 cells to explore the role of hucMSCs in improving α-cell mitochondrial dysfunction and hyperglucagonemia. Plasma and supernatant glucagon were detected by enzyme-linked immunosorbent assay (ELISA). Mitochondrial function of α cells was assessed by the Seahorse Analyzer. To investigate the underlying mechanisms, Sirtuin 1 (SIRT1), Forkhead box O3a (FoxO3a), glucose transporter type1 (GLUT1), and glucokinase (GCK) were assessed by Western blotting analysis. In vivo, hucMSC infusion improved glucose and insulin tolerance, as well as hyperglycemia and hyperglucagonemia in T2DM mice. Meanwhile, hucMSC intervention rescued the islet structure and decreased α- to ß-cell ratio. Glucagon secretion from αTC1-6 cells was consistently inhibited by hucMSCs in vitro. Meanwhile, hucMSC treatment activated intracellular SIRT1/FoxO3a signaling, promoted glucose uptake and activation, alleviated mitochondrial dysfunction, and enhanced ATP production. However, transfection of SIRT1 small interfering RNA (siRNA) or the application of SIRT1 inhibitor EX-527 weakened the therapeutic effects of hucMSCs on mitochondrial function and glucagon secretion. Our observations indicate that hucMSCs mitigate mitochondrial dysfunction and glucagon hypersecretion of α cells in T2DM via SIRT1/FoxO3a signaling, which provides novel evidence demonstrating the potential for hucMSCs in treating T2DM.

7.
Poult Sci ; 103(8): 103915, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38917611

RESUMO

This study determined metabolizable energy (ME) and developed ME prediction equations for broilers based on chemical composition of soybean meal (SBM) and rapeseed meal (RSM) using a 2 × 10 factorial arrangement of age (11 to 14 or 25 to 28 d of age) and 10 sources of each ingredient. Each treatment contained 6 replicates of 8 broilers. The ME values were determined by total collection of feces and urine. Principal components analysis (PCA) of the chemical composition clearly revealed distinct differences in SBM and RSM based on a principal components (PC) score plot. The nitrogen-corrected apparent metabolizable energy (AMEn) of SBM was higher in broilers from 25 to 28 than 11 to 14 d of age (P = 0.013). Interactions between broiler age and ingredient source affected apparent metabolizable energy (AME) of SBM and ME of RSM (P < 0.05). The ME of SBM in 11 to 14 and 25 to 28-day-old broilers were estimated by crude protein (CP) content (R2≥ 0.782; SEP ≤ 83 kcal/kg DM; P < 0.001). The AME and AMEn of RSM in 11 to 14-day-old broilers were estimated by ether extract (EE), ash and acid detergent fiber (ADF) (R2 = 0.897, SEP = 106 kcal/kg DM; P = 0.002), and by EE and ash (R2 = 0.885, SEP = 98 kcal/kg DM; P = 0.001), respectively. The AME and AMEn of RSM in 25 to 28-day-old broilers were estimated by ash and ADF (R2 = 0.925, SEP = 104 kcal/kg DM; P < 0.001) and by ash and neutral detergent fiber (NDF) (R2 = 0.921, SEP = 91 kcal/kg DM; P < 0.001), respectively. These results indicate that ME of these 2 plant protein ingredients are affected interactively by chemical composition and age of broilers. This study developed robust, age-specific prediction equations of ME for broilers based on chemical composition for SBM and RSM. Overall, ME values can be predicted from CP content for SBM, or EE, ash, ADF, and NDF for RSM.

8.
Sci Adv ; 10(26): eadl2675, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38941473

RESUMO

Declined memory is a hallmark of Alzheimer's disease (AD). Experiments in rodents and human postmortem studies suggest that serotonin (5-hydroxytryptamine, 5-HT) plays a role in memory, but the underlying mechanisms are unknown. Here, we investigate the role of 5-HT 2C receptor (5-HT2CR) in regulating memory. Transgenic mice expressing a humanized HTR2C mutation exhibit impaired plasticity of hippocampal ventral CA1 (vCA1) neurons and reduced memory. Further, 5-HT neurons project to and synapse onto vCA1 neurons. Disruption of 5-HT synthesis in vCA1-projecting neurons or deletion of 5-HT2CRs in the vCA1 impairs neural plasticity and memory. We show that a selective 5-HT2CR agonist, lorcaserin, improves synaptic plasticity and memory in an AD mouse model. Cumulatively, we demonstrate that hippocampal 5-HT2CR signaling regulates memory, which may inform the use of 5-HT2CR agonists in the treatment of dementia.


Assuntos
Doença de Alzheimer , Memória , Camundongos Transgênicos , Plasticidade Neuronal , Receptor 5-HT2C de Serotonina , Animais , Humanos , Receptor 5-HT2C de Serotonina/metabolismo , Receptor 5-HT2C de Serotonina/genética , Memória/efeitos dos fármacos , Memória/fisiologia , Camundongos , Plasticidade Neuronal/efeitos dos fármacos , Doença de Alzheimer/metabolismo , Hipocampo/metabolismo , Hipocampo/efeitos dos fármacos , Serotonina/metabolismo , Modelos Animais de Doenças , Região CA1 Hipocampal/metabolismo , Região CA1 Hipocampal/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/efeitos dos fármacos , Agonistas do Receptor 5-HT2 de Serotonina/farmacologia
9.
Healthcare (Basel) ; 12(11)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38891148

RESUMO

(1) Background: Illness perception (IP) is an important psychological construct for couples dealing with cancer, which impacts health outcomes and the psychological adjustment to cancer. More research is needed to explore the traits of IP and the efforts of couples coping with cancer. Thus, this study was designed to explore the coping experiences and features of the IPs of couples dealing with cancer. (2) Methods: A total of 24 patients with colorectal cancer (CRC) and 20 spousal caregivers (SCs) participated in semi-structured interviews. All interviews were recorded digitally, transcribed, and analyzed by using an inductive thematic analysis. (3) Results: Two themes (individualized and predominant IP; IP sharing and restructuring) were developed. A preliminary framework was formulated to illustrate the relations among subthemes and the relations between themes with an adjustment of a positive IP to CRC. In this framework, based on multiple sources and factors, the natural disparities formed the IPs of the partners of couples and determined the incongruence of IPs. The effects of IP incongruence on lives under the disease guided the three directions of coping approaches (i.e., information and available support, appropriate disclosure and reflection, and leaving the CRC diagnosis behind) which were adopted by couples dealing with CRC to share and restructure the IP with their spouses for effective dyadic coping. (4) Conclusions: This study provides insights to healthcare providers into the experiences of couples dealing with CRC and the development of couple-based IP intervention programs: (a) it initially provides adequate factual knowledge for enhancing beliefs in the ability to control illness, (b) encourages illness-centered conversations and disclosure regarding thoughts and emotions for promoting positive congruence of IP between the partners of couples dealing with a hard dilemma, and (c) guides couples to perceive positive changes and explore the illness's meaning. Understanding each theme of personalized IP and adopting effective IP coping approaches can help guide couples dealing with CRC to efficiently promote constructive IP and better health outcomes.

10.
J Neurosci ; 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38897723

RESUMO

Light plays an essential role in a variety of physiological processes, including vision, mood, and glucose homeostasis. However, the intricate relationship between light and an animal's feeding behavior has remained elusive. Here, we found that light exposure suppresses food intake, whereas darkness amplifies it in male mice. Interestingly, this phenomenon extends its reach to diurnal male Nile grass rats and healthy humans. We further show that lateral habenula (LHb) neurons in mice respond to light exposure, which in turn activates 5-HT neurons in the dorsal Raphe nucleus (DRN). Activation of the LHb → 5-HTDRN circuit in mice blunts darkness-induced hyperphagia, while inhibition of the circuit prevents light-induced anorexia. Together, we discovered a light responsive neural circuit that relays the environmental light signals to regulate feeding behavior in mice.Significance statement Feeding behavior is influenced by a myriad of sensory inputs, but the impact of light exposure on feeding regulation has remained enigmatic. Here, we showed that light exposure diminishes food intake across both nocturnal and diurnal species. Delving deeper, our findings revealed that the LHb → 5-HTDRN neural circuit plays a pivotal role in mediating light-induced anorexia in mice. These discoveries not only enhance our comprehension of the intricate neuronal mechanisms governing feeding in response to light but also offer insights for developing innovative strategies to address obesity and eating disorders.

11.
Front Oncol ; 14: 1336763, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38903724

RESUMO

Background: Kaposiform hemangioendothelioma (KHE) is a rare vascular tumor with a high risk of mortality. Few studies with large samples of KHE have been reported. KHE may develop into the Kasabach-Merritt phenomenon (KMP), which is characterized by thrombocytopenia and consumptive coagulopathy. The features of severe symptomatic anemia and life-threatening low platelets make the management of KHE associated with KMP challenging. Objective: The aim of this study was to examine the clinical characteristics of patients with KHE and discuss the treatment experience for different risk groups of KHE. Methods: Through a retrospective review of 70 patients diagnosed with KHE between 2017 and 2022 in our center, we classify lesions into three clinicopathological stages based on the tumor involving depth, and divided the severity of KHE into three levels by estimating clinicopathological stages and severity of thrombocytopenia. Treatments of different severity groups were estimated with sufficient data. Results: In our cohort, 27% were neonates, and KHE lesion occurred at birth in 84% of patients. There was a slight male predominance (32 girls and 38 boys). Common clinical characteristics included associated coagulation disorder (100%), locally aggressive cutaneous blue-purple mass (89%), thrombocytopenia (78%), and local pain or joint dysfunction (20%). The lower extremities were the dominant location (35%), followed by the trunk (29%), the maxillofacial region and neck (24%), and the upper extremities (10%). Of the total cohort, 78% developed KMP; the median age at which thrombocytopenia occurred was 27.8 days. The median platelet count of patients who were associated with KMP was 24,000/µL in our cohort. Ninety-two percent of patients were given surgery treatment and 89% of these patients were given high-dose methylprednisolone (5-6 mg/kg daily) before surgery. In 55 patients with KMP, 36% were sensitive to high-dose corticosteroid therapy. Patients from the low-risk group (eight cases) underwent operation, all of whom recovered without recurrence after a maximum follow-up of 5 years. Out of 26 patients from the high-risk group, 25 underwent surgery treatment, with 1 case undergoing secondary surgery after recurrence and 1 case taking sirolimus. Out of 36 cases from the extremely high-risk group, 32 underwent surgery (including 2 cases who underwent external carotid artery ligation and catheterization), 3 of whom underwent secondary operation after recurrence, and the remaining 4 cases took medicine. The mean length of having sirolimus was 21 months; two cases stopped taking sirolimus due to severe pneumonia. Two cases died at 1 and 3 months after discharge. Conclusions: Our study describes the largest assessment of high-risk patients with KHE who have undergone an operation to date, with 5 years of follow-up to track recovery, which provides invaluable knowledge for the future treatment of patients with KHE and KMP from different risk groups: Early surgical intervention may be the most definitive treatment option for most patients with KHE; multimodality treatment is the best choice for the extremely high-risk group.

13.
ISA Trans ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38797647

RESUMO

In this paper, a novel fixed-time non-singular terminal sliding mode control (NFNTSMC) method with an adaptive neural network (ANN) is proposed for permanent magnet synchronous motor (PMSM) system to improve PMSM performance. For nominal PMSM system without disturbance, a novel fixed-time non-singular terminal sliding mode control is designed to achieve fixed-time convergence property to improve the dynamic performance of the system. However, parameters mismatch and external load disturbances generally exist in PMSM system, the controller designed by NFNTSMC requires a large switching gain to ensure the robustness of the system, which will cause high-frequency sliding mode chattering. Therefore, an adaptive radial basis function (RBF) neural network is designed to approximate the unknown nonlinear lumped disturbance including parameters mismatch and external load disturbances online, and then the output of the neural network can be compensated to the NFNTSMC controller to reduce the switching gain and sliding mode chattering. Finally, the fixed-time convergence property and stability of the system are proved by Lyapunov method. The simulation and experimental results show that the presented strategy possesses satisfactory dynamic performance and strong robustness for PMSM system. And the proposed control scheme also provides an effective and systematic idea of the controller design for PMSM.

14.
bioRxiv ; 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38746443

RESUMO

Physical exercise represents a primary defense against age-related cognitive decline and neurodegenerative disorders like Alzheimer's disease (AD). To impartially investigate the underlying mechanisms, we conducted single-nucleus transcriptomic and chromatin accessibility analyses (snRNA-seq and ATAC-seq) on the hippocampus of mice carrying AD-linked NL-G-F mutations in the amyloid precursor protein gene (APPNL-G-F) following prolonged voluntary wheel-running exercise. Our study reveals that exercise mitigates amyloid-induced changes in both transcriptomic expression and chromatin accessibility through cell type-specific transcriptional regulatory networks. These networks converge on the activation of growth factor signaling pathways, particularly the epidermal growth factor receptor (EGFR) and insulin signaling, correlating with an increased proportion of immature dentate granule cells and oligodendrocytes. Notably, the beneficial effects of exercise on neurocognitive functions can be blocked by pharmacological inhibition of EGFR and the downstream phosphoinositide 3-kinases (PI3K). Furthermore, exercise leads to elevated levels of heparin-binding EGF (HB-EGF) in the blood, and intranasal administration of HB-EGF enhances memory function in sedentary APPNL-G-F mice. These findings offer a panoramic delineation of cell type-specific hippocampal transcriptional networks activated by exercise and suggest EGF-related growth factor signaling as a druggable contributor to exercise-induced memory enhancement, thereby suggesting therapeutic avenues for combatting AD-related cognitive decline.

15.
Nat Commun ; 15(1): 4098, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750065

RESUMO

Probabilistic computing is a computing scheme that offers a more efficient approach than conventional complementary metal-oxide-semiconductor (CMOS)-based logic in a variety of applications ranging from optimization to Bayesian inference, and invertible Boolean logic. The probabilistic bit (or p-bit, the base unit of probabilistic computing) is a naturally fluctuating entity that requires tunable stochasticity; by coupling low-barrier stochastic magnetic tunnel junctions (MTJs) with a transistor circuit, a compact implementation is achieved. In this work, by combining stochastic MTJs with 2D-MoS2 field-effect transistors (FETs), we demonstrate an on-chip realization of a p-bit building block displaying voltage-controllable stochasticity. Supported by circuit simulations, we analyze the three transistor-one magnetic tunnel junction (3T-1MTJ) p-bit design, evaluating how the characteristics of each component influence the overall p-bit output. While the current approach has not reached the level of maturity required to compete with CMOS-compatible MTJ technology, the design rules presented in this work are valuable for future experimental implementations of scaled on-chip p-bit networks with reduced footprint.

16.
bioRxiv ; 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38746249

RESUMO

Clostridioides difficile infection (CDI) is one of the leading causes of healthcare- and antibiotic-associated diarrhea. While fecal microbiota transplantation (FMT) has emerged as a promising therapy for recurrent CDI, its exact mechanisms of action and long-term safety are not fully understood. Defined consortia of clonal bacterial isolates, known as live biotherapeutic products (LBPs), have been proposed as an alternative therapeutic option. However, the rational design of LBPs remains challenging. Here, we employ a computational pipeline and three independent metagenomic datasets to systematically identify microbial strains that have the potential to inhibit CDI. We first constructed the CDI-related microbial genome catalog, comprising 3,741 non-redundant metagenome-assembled genomes (nrMAGs) at the strain level. We then identified multiple potential protective nrMAGs that can be candidates for the design of microbial consortia targeting CDI, including strains from Dorea formicigenerans, Oscillibacter welbionis, and Faecalibacterium prausnitzii. Importantly, some of these potential protective nrMAGs were found to play an important role in the success of FMT, and the majority of the top protective nrMAGs can be validated by various previously reported findings. Our results demonstrate a computational framework for the rational selection of microbial strains targeting CDI, paving the way for the computational design of microbial consortia against other enteric infections.

17.
Nat Commun ; 15(1): 3783, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38710722

RESUMO

General, catalytic and enantioselective construction of chiral α,α-dialkyl indoles represents an important yet challenging objective to be developed. Herein we describe a cobalt catalyzed enantioselective anti-Markovnikov alkene hydroalkylation via the remote stereocontrol for the synthesis of α,α-dialkyl indoles and other N-heterocycles. This asymmetric C(sp3)-C(sp3) coupling features high flexibility in introducing a diverse set of alkyl groups at the α-position of chiral N-heterocycles. The utility of this methodology has been demonstrated by late-stage functionalization of drug molecules, asymmetric synthesis of bioactive molecules, natural products and functional materials, and identification of a class of molecules exhibiting anti-apoptosis activities in UVB-irradiated HaCaT cells. Ligands play a vital role in controlling the reaction regioselectivity. Changing the ligand from bi-dentate L6 to tridentate L12 enables CoH-catalyzed Markovnikov hydroalkylation. Mechanistic studies disclose that the anti-Markovnikov hydroalkylation involves a migratory insertion process while the Markovnikov hydroalkylation involves a MHAT process.

18.
Front Cell Infect Microbiol ; 14: 1341545, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38779561

RESUMO

Background: Engaging in anal sexual intercourse markedly increases the risk of developing HIV among men who have sex with men (MSM); oral sexual activities tend to uniquely introduce gut-derived microbes to salivary microbiota, which, combined with an individual's positive HIV status, may greatly perturb oral microecology. However, till date, only a few published studies have addressed this aspect. Methods: Based on 16S rRNA sequencing data of bacterial taxa, MicroPITA picks representative samples for metagenomic analysis, effectively revealing how the development and progression of the HIV disease influences oral microbiota in MSM. Therefore, we collected samples from 11 HIV-negative and 44 HIV-positive MSM subjects (stage 0 was defined by HIV RNA positivity, but negative or indeterminate antibody status; stages 1, 2, and 3 were defined by CD4+ T lymphocyte counts ≥ 500, 200-499, and ≤ 200 or opportunistic infection) and selected 25 representative saliva samples (5 cases/stage) using MicroPITA. Metagenomic sequencing analysis were performed to explore whether positive HIV status changes salivary bacterial KEGG function and metabolic pathway in MSM. Results: The core functions of oral microbiota were maintained across each of the five groups, including metabolism, genetic and environmental information processing. All HIV-positive groups displayed KEGG functions of abnormal proliferation, most prominently at stage 0, and others related to metabolism. Clustering relationship analysis tentatively identified functional relationships between groups, with bacterial function being more similar between stage 0-control groups and stage 1-2 groups, whereas the stage 3 group exhibited large functional changes. Although we identified most metabolic pathways as being common to all five groups, several unique pathways formed clusters for certain groups; the stage 0 group had several, while the stage 2 and 3 groups had few, such clusters. The abundance of K03046 was positively correlated with CD4 counts. Conclusion: As HIV progresses, salivary bacterial function and metabolic pathways in MSM progressively changes, which may be related to HIV promoting abnormal energy metabolism and exacerbate pathogen virulence. Further, infection and drug resistance of acute stage and immune cell destruction of AIDS stage were abnormally increased, predicting an increased risk for MSM individuals to develop systemic and oral diseases.


Assuntos
Infecções por HIV , Homossexualidade Masculina , RNA Ribossômico 16S , Saliva , Humanos , Masculino , Saliva/microbiologia , Saliva/virologia , Infecções por HIV/microbiologia , RNA Ribossômico 16S/genética , Adulto , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Microbiota , Metagenômica , Contagem de Linfócito CD4 , Pessoa de Meia-Idade , Adulto Jovem , Minorias Sexuais e de Gênero
19.
J Am Chem Soc ; 146(19): 13467-13476, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38709001

RESUMO

Electrostatic energy-storage ceramic capacitors are essential components of modern electrified power systems. However, improving their energy-storage density while maintaining high efficiency to facilitate cutting-edge miniaturized and integrated applications remains an ongoing challenge. Herein, we report a record-high energy-storage density of 20.3 J cm-3 together with a high efficiency of 89.3% achieved by constructing a relaxor ferroelectric state with strongly enhanced local polarization fluctuations. This is realized by incorporating highly polarizable, heterovalent, and large-sized Zn and Nb ions into a Bi0.5Na0.5TiO3-BaTiO3 ferroelectric matrix with very strong tetragonal distortion. Element-specific local structure analysis revealed that the foreign ions strengthen the magnitude of the unit-cell polarization vectors while simultaneously reducing their orientation anisotropy and forming strong fluctuations in both magnitude and orientation within 1-3 nm polar clusters. This leads to a particularly high polarization variation (ΔP) of 72 µC cm-2, low hysteresis, and a high effective polarization coefficient at a high breakdown strength of 80 kV mm-1. This work has surpassed the current energy density limit of 20 J cm-3 in bulk Pb-free ceramics and has demonstrated that controlling the local structure via the chemical composition design can open up new possibilities for exploring relaxors with high energy-storage performance.

20.
Front Plant Sci ; 15: 1360173, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38751839

RESUMO

Tobacco (Nicotiana tabacum L.) bacterial wilt, caused by Ralstonia solanacearum, is indeed a highly destructive plant disease, leading to substantial damage in tobacco production. While biological control is considered an effective measure for managing bacterial wilt, related research in this area has been relatively limited compared to other control methods. In order to discover new potential antagonistic bacteria with high biocontrol efficacy against tobacco bacterial wilt, we conducted an analysis of the microbial composition differences between disease-suppressive and disease-conducive soils using Illumina sequencing. As a result, we successfully isolated six strains from the disease-suppressive soil that exhibited antibacterial activity against Ralstonia solanacearum. Among these strains, B4-7 showed the strongest antibacterial activity, even at acidic conditions with a pH of 4.0. Based on genome analysis using Average Nucleotide Identity (ANI), B4-7 was identified as Bacillus velezensis. In greenhouse and field trials, strain B4-7 significantly reduced the disease index of tobacco bacterial wilt, with control efficiencies reaching 74.03% and 46.88% respectively. Additionally, B4-7 exhibited plant-promoting abilities that led to a 35.27% increase in tobacco production in field conditions. Quantitative real-time (qPCR) analysis demonstrated that strain B4-7 effectively reduced the abundance of R. solanacearum in the rhizosphere. Genome sequencing and Liquid Chromatography-Mass Spectrometry (LC-MS) analysis revealed that strain B4-7 potentially produces various lipopeptide metabolites, such as microlactin, bacillaene, difficidin, bacilysin, and surfactin. Furthermore, B4-7 influenced the structure of the rhizosphere soil microbial community, increasing bacterial abundance and fungal diversity, while also promoting the growth of different beneficial microorganisms. In addition, B4-7 enhanced tobacco's resistance to R. solanacearum by increasing the activities of defense enzymes, including superoxide dismutase (SOD), phenylalanine ammonia-lyase (PAL), peroxidase (POD), catalase (CAT), and polyphenol oxidase (PPO). Collectively, these findings suggest that B. velezensis B4-7 holds significant biocontrol potential and can be considered a promising candidate strain for eco-friendly management of tobacco bacterial wilt.

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