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1.
Phys Rev Lett ; 132(11): 113802, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38563911

RESUMO

Quantum Hall systems host chiral edge states extending along the one-dimensional boundary of any two-dimensional sample. In solid state materials, the edge states serve as perfectly robust transport channels that produce a quantized Hall conductance; due to their chirality, and the topological protection by the Chern number of the bulk band structure, they cannot be spatially localized by defects or disorder. Here, we show experimentally that the chiral edge states of a lossy quantum Hall system can be localized. In a gyromagnetic photonic crystal exhibiting the quantum Hall topological phase, an appropriately structured loss configuration imparts the edge states' complex energy spectrum with a feature known as point-gap winding. This intrinsically non-Hermitian topological invariant is distinct from the Chern number invariant of the bulk (which remains intact) and induces mode localization via the "non-Hermitian skin effect." The interplay of the two topological phenomena-the Chern number and point-gap winding-gives rise to a non-Hermitian generalization of the paradigmatic Chern-type bulk-boundary correspondence principle. Compared to previous realizations of the non-Hermitian skin effect, the skin modes in this system have superior robustness against local defects and disorders.

2.
Interdiscip Sci ; 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38581626

RESUMO

Exploration of the intricate connections between long noncoding RNA (lncRNA) and diseases, referred to as lncRNA-disease associations (LDAs), plays a pivotal and indispensable role in unraveling the underlying molecular mechanisms of diseases and devising practical treatment approaches. It is imperative to employ computational methods for predicting lncRNA-disease associations to circumvent the need for superfluous experimental endeavors. Graph-based learning models have gained substantial popularity in predicting these associations, primarily because of their capacity to leverage node attributes and relationships within the network. Nevertheless, there remains much room for enhancing the performance of these techniques by incorporating and harmonizing the node attributes more effectively. In this context, we introduce a novel model, i.e., Adaptive Message Passing and Feature Fusion (AMPFLDAP), for forecasting lncRNA-disease associations within a heterogeneous network. Firstly, we constructed a heterogeneous network involving lncRNA, microRNA (miRNA), and diseases based on established associations and employing Gaussian interaction profile kernel similarity as a measure. Then, an adaptive topological message passing mechanism is suggested to address the information aggregation for heterogeneous networks. The topological features of nodes in the heterogeneous network were extracted based on the adaptive topological message passing mechanism. Moreover, an attention mechanism is applied to integrate both topological and semantic information to achieve the multimodal features of biomolecules, which are further used to predict potential LDAs. The experimental results demonstrated that the performance of the proposed AMPFLDAP is superior to seven state-of-the-art methods. Furthermore, to validate its efficacy in practical scenarios, we conducted detailed case studies involving three distinct diseases, which conclusively demonstrated AMPFLDAP's effectiveness in the prediction of LDAs.

3.
J Med Virol ; 96(4): e29594, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38576317

RESUMO

The HIV capsid (CA) protein is a promising target for anti-AIDS treatment due to its critical involvement in viral replication. Herein, we utilized the well-documented CA inhibitor PF74 as our lead compound and designed a series of low-molecular-weight phenylalanine derivatives. Among them, compound 7t exhibited remarkable antiviral activity with a high selection index (EC50 = 0.040 µM, SI = 2815), surpassing that of PF74 (EC50 = 0.50 µM, SI = 258). Furthermore, when evaluated against the HIV-2 strain, 7t (EC50 = 0.13 µM) demonstrated approximately 14-fold higher potency than that of PF74 (EC50 = 1.76 µM). Insights obtained from surface plasmon resonance (SPR) revealed that 7t exhibited stronger target affinity to the CA hexamer and monomer in comparison to PF74. The potential interactions between 7t and the HIV-1 CA were further elucidated using molecular docking and molecular dynamics simulations, providing a plausible explanation for the enhanced target affinity with 7t over PF74. Moreover, the metabolic stability assay demonstrated that 7t (T1/2 = 77.0 min) significantly outperforms PF74 (T1/2 = 0.7 min) in human liver microsome, exhibiting an improvement factor of 110-fold. In conclusion, 7t emerges as a promising drug candidate warranting further investigation.


Assuntos
Fármacos Anti-HIV , Soropositividade para HIV , Humanos , Capsídeo/metabolismo , Fenilalanina/farmacologia , Fenilalanina/metabolismo , Simulação de Acoplamento Molecular , Fármacos Anti-HIV/farmacologia , Proteínas do Capsídeo/metabolismo , Antirretrovirais
4.
Brief Bioinform ; 25(3)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38581416

RESUMO

The inference of gene regulatory networks (GRNs) from gene expression profiles has been a key issue in systems biology, prompting many researchers to develop diverse computational methods. However, most of these methods do not reconstruct directed GRNs with regulatory types because of the lack of benchmark datasets or defects in the computational methods. Here, we collect benchmark datasets and propose a deep learning-based model, DeepFGRN, for reconstructing fine gene regulatory networks (FGRNs) with both regulation types and directions. In addition, the GRNs of real species are always large graphs with direction and high sparsity, which impede the advancement of GRN inference. Therefore, DeepFGRN builds a node bidirectional representation module to capture the directed graph embedding representation of the GRN. Specifically, the source and target generators are designed to learn the low-dimensional dense embedding of the source and target neighbors of a gene, respectively. An adversarial learning strategy is applied to iteratively learn the real neighbors of each gene. In addition, because the expression profiles of genes with regulatory associations are correlative, a correlation analysis module is designed. Specifically, this module not only fully extracts gene expression features, but also captures the correlation between regulators and target genes. Experimental results show that DeepFGRN has a competitive capability for both GRN and FGRN inference. Potential biomarkers and therapeutic drugs for breast cancer, liver cancer, lung cancer and coronavirus disease 2019 are identified based on the candidate FGRNs, providing a possible opportunity to advance our knowledge of disease treatments.


Assuntos
Redes Reguladoras de Genes , Neoplasias Hepáticas , Humanos , Biologia de Sistemas/métodos , Transcriptoma , Algoritmos , Biologia Computacional/métodos
5.
Food Chem ; 448: 139210, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38569408

RESUMO

The detection of heavy metals in tea infusions is important because of the potential health risks associated with their consumption. Existing highly sensitive detection methods pose challenges because they are complicated and time-consuming. In this study, we developed an innovative and simple method using Ag nanoparticles-modified resin (AgNPs-MR) for pre-enrichment prior to laser-induced breakdown spectroscopy for the simultaneous analysis of Cr (III), Cu (II), and Pb (II) in tea infusions. Signal enhancement using AgNPs-MR resulted in amplification with limits of detection of 0.22 µg L-1 for Cr (III), 0.33 µg L-1 for Cu (II), and 1.25 µg L-1 for Pb (II). Quantitative analyses of these ions in infusions of black tea from various brands yielded recoveries ranging from 83.3% to 114.5%. This method is effective as a direct and highly sensitive technique for precisely quantifying trace concentrations of heavy metals in tea infusions.


Assuntos
Cromo , Cobre , Contaminação de Alimentos , Chumbo , Nanopartículas Metálicas , Prata , Chá , Chá/química , Cromo/análise , Chumbo/análise , Prata/química , Nanopartículas Metálicas/química , Cobre/análise , Contaminação de Alimentos/análise , Análise Espectral/métodos , Lasers , Camellia sinensis/química , Metais Pesados/análise , Limite de Detecção
6.
Front Oncol ; 14: 1326626, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38505588

RESUMO

Introduction: Solid adenocarcinoma represents a notably aggressive subtype of lung adenocarcinoma. Amidst the prevailing inclination towards conservative surgical interventions for diminutive lung cancer lesions, the critical evaluation of this subtype's malignancy and heterogeneity stands as imperative for the formulation of surgical approaches and the prognostication of long-term patient survival. Methods: A retrospective dataset, encompassing 2406 instances of non-solid adenocarcinoma (comprising lepidic, acinar, and papillary adenocarcinoma) and 326 instances of solid adenocarcinoma, was analyzed to ascertain the risk factors concomitant with diverse histological variants of lung adenocarcinoma. Concurrently, RNA-sequencing data delineating explicit pathological subtypes were extracted from 261 cases in the TCGA database and 188 cases in the OncoSG database. This data served to illuminate the heterogeneity across lung adenocarcinoma (LUAD) specimens characterized by differential histological features. Results: Solid adenocarcinoma is associated with an elevated incidence of pleural invasion, microscopic vessel invasion, and lymph node metastasis, relative to other subtypes of lung adenocarcinoma. Furthermore, the tumor microenvironment (TME) in solid pattern adenocarcinoma displayed suboptimal oxygenation and acidic conditions, concomitant with augmented tumor cell proliferation and invasion capacities. Energy and metabolic activities were significantly upregulated in tumor cells of the solid pattern subtype. This subtype manifested robust immune tolerance and capabilities for immune evasion. Conclusion: This present investigation identifies multiple potential metrics for evaluating the invasive propensity, metastatic likelihood, and immune resistance of solid pattern adenocarcinoma. These insights may prove instrumental in devising surgical interventions that are tailored to patients diagnosed with disparate histological subtypes of LUAD, thereby offering valuable directional guidance.

7.
Artigo em Inglês | MEDLINE | ID: mdl-38507172

RESUMO

Long non-coding RNA (lncRNA) is associated with a large number of tumor cellular functions together with chemotherapy resistance in a variety of tumors. LINC00963 was identified to regulate the malignant progression of various cancers. However, whether LINC00963 affects drug resistence in esophageal squamous cell carcinoma (ESCC) and the relevant molecular mechanisms have never been reported. This study aims to investigate the effect of LINC00963 on cisplatin resistance in ESCC. After detecting the level of LINC00963 in human esophageal squamous epithelial cells (HET-1 A), ESCC cells (TE-1) and cisplatin resistant cells of ESCC (TE-1/DDP), TE-1/DDP cell line and nude mouse model that interfered with LINC00963 expression were established. Then, the interaction among LINC00963, miR-10a, and SKA1 was clarified by double luciferase and RNA immunoprecipitation (RIP) assays. Meanwhile, the biological behavior changes of TE-1/DDP cells with miR-10a overexpression or SKA1 silencing were observed by CCK-8, flow cytometry, scratch, Transwell, and colony formation tests. Finally, the biological function of the LINC00963/SKA1 axis was elucidated by rescue experiments. LINC00963 was upregulated in TE-1 and TE-1/DDP cell lines. LINC00963 knockdown inhibited SKA1 expression of both cells and impaired tumorigenicity. Moreover, LINC00963 has a target relationship with miR-10a, and SKA1 is a target gene of miR-10a. MiR-10a overexpression or SKA1 silencing decreased the biological activity of TE-1/DDP cells and the expression of SKA1. Furthermore, SKA1 overexpression reverses the promoting effect of LINC00963 on cisplatin resistance of ESCC. LINC00963 regulates TE-1/DDP cells bioactivity and mediates cisplatin resistance through interacting with miR-10a and upregulating SKA1 expression.

8.
Acta Pharm Sin B ; 14(3): 1257-1282, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38486991

RESUMO

With our continuous endeavors in seeking potent anti-HIV-1 agents, we reported here the discovery, biological characterization, and druggability evaluation of a class of nonnucleoside reverse transcriptase inhibitors. To fully explore the chemical space of the NNRTI-binding pocket, novel series of dihydrothiopyrano [3,2-d]pyrimidines were developed by employing the structure-based design strategy. Most of the derivatives were endowed with prominent antiviral activities against HIV-1 wild-type and resistant strains at nanomolar levels. Among them, compound 23h featuring the aminopiperidine moiety was identified as the most potent inhibitor, with EC50 values ranging from 3.43 to 21.4 nmol/L. Especially, for the challenging double-mutants F227L + V106A and K103N + Y181C, 23h exhibited 2.3- to 14.5-fold more potent activity than the first-line drugs efavirenz and etravirine. Besides, the resistance profiles of 23h achieved remarkable improvement compared to efavirenz and etravirine. The binding target of 23h was further confirmed to be HIV-1 reverse transcriptase. Molecular modeling studies were also performed to elucidate the biological evaluation results and give guidance for the optimization campaign. Furthermore, no apparent inhibition of the major CYP450 enzymes and hERG channel was observed for 23h. Most importantly, 23h was characterized by good pharmacokinetic properties and excellent safety in vivo. Collectively, 23h holds great promise as a potential candidate for its effective antiviral efficacy and favorable drug-like profiles.

9.
Obes Surg ; 34(4): 1333-1342, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38427150

RESUMO

BACKGROUND: Liver fibrosis is a predisposing factor for liver cancer. This study will investigate the predictive role of the Triglyceride-glucose and Gamma-glutamyl transferase index (TyG-GGT) as a non-invasive indicator of advanced liver fibrosis in individuals with obesity or overweight. METHOD: We enrolled patients who underwent metabolic and bariatric surgery as well as intraoperative liver biopsies at Zhejiang provincial people's hospital from August 2020 to March 2023. Clinical characteristics, comorbidities, laboratory data, and pathological variables of patients were collected and analysed. Then, we conducted logistics regression model to compare the performance of the TyG-GGT index with other 4 non-invasive models. RESULTS: A total of 65 patients were included in this study. 43(66.2%) of them were female, with the mean body mass index (BMI) of 39.0 ± 7.3 kg/m2. Meanwhile, 24(36.9%) patients were diagnosed with diabetes. Advanced liver fibrosis were observed in 16.9% of patients, while liver cirrhosis was found in 4.6% of patients. The multivariable logistics regression showed that TyG-GGT was an independent risk factor of advanced liver fibrosis (OR = 6.989, P = 0.049). Additionally, compared to another 4 non-invasive liver fibrosis models (NFS = 0.66, FIB4 = 0.65, METS-IR = 0.68, APRI = 0.65), TyG-GGT exhibits the highest AUC value of 0.75. CONCLUSIONS: More than one-third of patients undergoing metabolic and bariatric surgery are afflicted with nonalcoholic steatohepatitis (NASH), and a significant proportion exhibit advanced fibrosis. TyG-GGT was a potentially reliable predictor for screening individuals with overweight or obesity at high risk of advanced liver fibrosis, thus providing clinical guidance for early intervention in this targeted group.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Obesidade Mórbida , Humanos , Feminino , Masculino , Sobrepeso , Obesidade Mórbida/cirurgia , Cirrose Hepática/diagnóstico , Obesidade , Fibrose
10.
Stem Cell Res ; 76: 103376, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38452706

RESUMO

The ISL LIM homeobox 1 (ISL1) gene belongs to the LIM/homeodomain transcription factor family and plays a pivotal role in conveying multipotent and proliferative properties of cardiac precursor cells. Mutations in ISL1 are linked to congenital heart disease. To further explore ISL1's role in the human heart, we have created a homozygous ISL1 knockout (ISL1-KO) human embryonic stem cell line using the CRISPR/Cas9 system. Notably, this ISL1-KO cell line retains normal morphology, pluripotency, and karyotype. This resource serves as a valuable tool for investigating ISL1's function in cardiomyocyte differentiation.


Assuntos
Sistemas CRISPR-Cas , Células-Tronco Embrionárias Humanas , Humanos , Sistemas CRISPR-Cas/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Linhagem Celular , Coração , Células-Tronco Embrionárias/metabolismo , Células-Tronco Embrionárias Humanas/metabolismo , Proteínas com Homeodomínio LIM/genética
11.
Adv Healthc Mater ; : e2304432, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38462702

RESUMO

Vascular diseases are the leading cause of ischemic necrosis in tissues and organs, necessitating using vascular grafts to restore blood supply. Currently, small vessels for coronary artery bypass grafts are unavailable in clinical settings. Decellularized small-diameter tissue-engineered vessel grafts (SD-TEVGs) hold significant potential. However, they face challenges, as simple implantation of decellularized SD-TEVGs in animals leads to thrombosis and calcification due to incomplete endothelialization. Consequently, research and development focus has shifted toward enhancing the endothelialization process of decellularized SD-TEVGs. This paper reviews preclinical studies involving decellularized SD-TEVGs, highlighting different strategies and their advantages and disadvantages for achieving rapid endothelialization of these vascular grafts. Methods are analyzed to improve the process while addressing potential shortcomings. This paper aims to contribute to the future commercial viability of decellularized SD-TEVGs.

12.
Zhongguo Zhen Jiu ; 44(3): 245-250, 2024 Mar 12.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38467496

RESUMO

OBJECTIVES: To observe the clinical efficacy of acupotomy combined with metformin hydrochloride tablet for type 2 diabetes mellitus (T2DM) and its effect on serum levels of inflammatory factors. METHODS: A total of 68 patients with T2DM were randomized into an acupotomy group (34 cases, 2 cases dropped out) and a western medication group (34 cases, 2 cases dropped out). Metformin hydrochloride tablet was given orally in the western medication group, 0.5-1 g each time, twice a day, for continuous 8 weeks. On the basis of the treatment in the western medication group, acupotomy was applied at bilateral Geshu (BL 17), Weiwanxiashu (EX-B 3), Ganshu (BL 18) in the acupotomy group, once a week for continuous 8 weeks. Before and after treatment, in the two groups, blood glucose (fasting blood glucose [FBG], 2-hour plasma glucose [2 h PG] and glycosylated hemoglobin [HbA1c]), TCM syndrome score, blood lipids (total cholesterol [TC], triglyceride [TG], low density lipoprotein cholesterol [LDL-C] and high density lipoprotein cholesterol [HDL-C]), insulin (fasting insulin [FINS] and 2-hour insulin [2 h INS]), C-peptide indexes (fasting C-peptide [FC-P] and 2-hour C-peptide [2 h C-P]), dosage of metformin hydrochloride tablet and diabetes specific quality of life (DSQL) score were observed, the serum levels of tumor necrosis factor (TNF)-α, interleukin (IL)-6 and IL-17 were measured by ELISA. RESULTS: After treatment, the FBG, 2 h PG, HbA1c, TCM syndrome scores, TC, TG, LDL-C, FINS, 2 h INS, FC-P, 2 h C-P, DSQL scores as well as the serum levels of TNF-α, IL-6, IL-17 were decreased compared with those before treatment (P<0.01), HDL-C was increased compared with that before treatment (P<0.01) in the two groups; the dosage of metformin hydrochloride tablet was decreased compared with that before treatment in the acupotomy group (P<0.01). After treatment, in the acupotomy group, the FBG, HbA1c, TCM syndrome score, TC, TG, LDL-C, FINS, 2 h INS, FC-P, 2 h C-P, dosage of metformin hydrochloride tablet, DSQL score as well as the serum level of TNF-α were lower than those in the western medication group (P<0.05). CONCLUSIONS: Acupotomy combined with metformin hydrochloride tablet can improve the blood glucose, clinical symptoms and quality of life in patients with T2DM, its mechanism may be related to the regulation of inflammatory reaction.


Assuntos
Terapia por Acupuntura , Diabetes Mellitus Tipo 2 , Metformina , Humanos , Glicemia , Peptídeo C , LDL-Colesterol , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hemoglobinas Glicadas , Interleucina-17 , Metformina/uso terapêutico , Qualidade de Vida , Comprimidos/uso terapêutico , Fator de Necrose Tumoral alfa
13.
Food Funct ; 15(6): 2860-2878, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38433710

RESUMO

Sex hormones play a pivotal role in the growth and development of the skeletal, neurological, and reproductive systems. In women, the dysregulation of sex hormones can result in various health complications such as acne, hirsutism, and irregular menstruation. One of the most prevalent diseases associated with excess androgens is polycystic ovary syndrome with a hyperandrogenic phenotype. Probiotics have shown the potential to enhance the secretion of ovarian sex hormones. However, the underlying mechanism of action remains unclear. Furthermore, comprehensive reviews detailing how probiotics modulate ovarian sex hormones are scarce. This review seeks to shed light on the potential mechanisms through which probiotics influence the production of ovarian sex hormones. The role of probiotics across various biological axes, including the gut-ovarian, gut-brain-ovarian, gut-liver-ovarian, gut-pancreas-ovarian, and gut-fat-ovarian axes, with a focus on the direct impact of probiotics on the ovaries via the gut and their effects on brain gonadotropins is discussed. It is also proposed herein that probiotics can significantly influence the onset, progression, and complications of ovarian sex hormone abnormalities. In addition, this review provides a theoretical basis for the therapeutic application of probiotics in managing sex hormone-related health conditions.


Assuntos
Hormônios Esteroides Gonadais , Síndrome do Ovário Policístico , Feminino , Humanos , Síndrome do Ovário Policístico/tratamento farmacológico , Hirsutismo/complicações , Hirsutismo/terapia , Distúrbios Menstruais/complicações , Distúrbios Menstruais/terapia
14.
J Med Chem ; 67(6): 5032-5052, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38482820

RESUMO

Gout and hyperuricemia are metabolic diseases characterized with high serum uric acid (SUA) levels that significantly impact human health. Lesinurad, a uricosuric agent, is limited to concurrent use with xanthine oxidase inhibitors (XOIs) in clinical practice due to its restricted efficacy and potential nephrotoxicity. Herein, extensive structural modifications of lesinurad were conducted through scaffold hopping and substituent modification strategies, affording 54 novel derivatives containing pyrimidine-fused cyclic structures. Notably, the thienopyrimidine compound 29 demonstrated a remarkable 2-fold increase in SUA-lowering in vivo activity compared to lesinurad, while exhibiting potent inhibitory activity against the urate transporter 1 (URAT1, IC50 = 2.01 µM) and glucose transporter 9 (GLUT9, IC50 = 18.21 µM). Furthermore, it possessed a lower effective dosage of 0.5 mg/kg, favorable safety profile without any apparent acute toxicity at doses of 1000 mg/kg, and improved pharmacokinetic properties. Overall, we have discovered an efficacious URAT1/GLUT9 dual inhibitor for inhibiting urate reabsorption with favorable pharmacokinetic profiles.


Assuntos
Gota , Hiperuricemia , Transportadores de Ânions Orgânicos , Tioglicolatos , Triazóis , Humanos , Ácido Úrico/uso terapêutico , Gota/tratamento farmacológico , Hiperuricemia/tratamento farmacológico , Uricosúricos/uso terapêutico , Pirimidinas/toxicidade , Pirimidinas/uso terapêutico , Proteínas Facilitadoras de Transporte de Glucose , Proteínas de Transporte de Cátions Orgânicos
15.
JACS Au ; 4(2): 454-464, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38425912

RESUMO

Nucleoside phosphorylases (NPs) are the key enzymes in the nucleoside metabolism pathway and are widely employed for the synthesis of nucleoside analogs, which are difficult to access via conventional synthetic methods. NPs are generally classified as purine nucleoside phosphorylase (PNP) and pyrimidine or uridine nucleoside phosphorylase (PyNP/UP), based on their substrate preference. Here, based on the evolutionary information on the NP-I family, we adopted an insertions-deletions (InDels) strategy to engineer the substrate promiscuity of nucleoside phosphorylase AmPNPΔS2V102 K, which exhibits both PNP and UP activities from a trimeric PNP (AmPNP) of Aneurinibacillus migulanus. Furthermore, the AmPNPΔS2V102 K exerted phosphorylation activities toward arabinose nucleoside, fluorosyl nucleoside, and dideoxyribose, thereby broadening the unnatural-ribose nucleoside substrate spectrum of AmPNP. Finally, six purine nucleoside analogues were successfully synthesized, using the engineered AmPNPΔS2V102 K instead of the traditional "two-enzymes PNP/UP" approach. These results provide deep insights into the catalytic mechanisms of the PNP and demonstrate the benefits of using the InDels strategy to achieve substrate promiscuity in an enzyme, as well as broadening the substrate spectrum of the enzyme.

16.
Exp Brain Res ; 242(4): 869-878, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38421411

RESUMO

Ischemic stroke is one of the most vital causes of high neurological morbidity and mortality in the world. Preconditioning exercise is considered as the primary prevention of stroke to resistance to subsequent injury. We tried to research the underlying biological mechanisms of this exercise. Forty-two SD rats were randomly divided into three groups: middle cerebral artery occlusion (MCAO) group, exercise group with MCAO (EX + MCAO) group, and sham group, with 14 rats in each group. The EX + MCAO group underwent exercise preconditioning for 3 weeks before occlusion, and the other two groups were fed and exercised normally. After 3 weeks, MCAO model was made by thread plug method in the EX + MCAO group and MCAO group. After successful modeling, the Longa scale was used to evaluate the neurological impairment of rats at day 0, day 1, and day 2. The rats in each group were killed on the third day after modeling. TTC staining measured the infarct volume of each group. The morphology and apoptosis of cortical cells were observed by HE and Tunel staining. Three rats in each group underwent high-throughput sequencing. Bioinformatic analysis was used to find the deferentially expressed genes (DEGs) and predict the transcription factor binding sites (TFBS) of the next-generation sequencing results. Gene enrichment (GSEA) was used to analyze potential functional genes and their corresponding signaling pathways. The Longa scale showed EX + MCAO group had the neurological function better than the modeling group (P < 0.001). TTC staining showed that the infarct size of EX + MCAO group was less than MCAO group (P < 0.05). HE and Tunel staining showed that the cells in the EX + MCAO group and the sham group had normal morphology and fewer apoptotic cells than MCAO group. A new gene named 7994 was discovered and TFBS of this gene was predicted, which could interact with key genes such as Foxd3, Foxa2, NR4A2, SP1, CEBPA, and SOX10. GSEA showed that EX + MCAO group could promote and regulate angiogenesis and apoptosis through PI3K-AKT pathway. Preconditioning exercise could improve nerve function and reduce infarct size in rats. The underlying mechanism is to regulate the PI3K-AKT pathway through several key genes, promote cerebral angiogenesis, and reduce apoptosis.


Assuntos
Lesões Encefálicas , Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Ratos , Animais , Ratos Sprague-Dawley , AVC Isquêmico/prevenção & controle , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Infarto da Artéria Cerebral Média , Encéfalo/metabolismo , Proteínas Repressoras , Fatores de Transcrição Forkhead/metabolismo
17.
Nanomaterials (Basel) ; 14(4)2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38392713

RESUMO

Exploring an appropriate immobilization approach to enhance catalytic activity and reusability of cellulase is of great importance to reduce the price of enzymes and promote the industrialization of cellulose-derived biochemicals. In this study, Fe3O4 magnetic nanoparticles (MNPs) were functionalized with meso-2,3-dimercaptosuccinic acid to introduce carboxyl groups on the surface (DMNPs). Then, melamine-glutaraldehyde dendrimer-like polymers were grafted on DMNPs to increase protein binding sites for the immobilization of processive endoglucanase EG5C-1. Moreover, this dendrimer-like structure was beneficial to protect the conformation of EG5C-1 and facilitate the interaction between substrate and active center. The loading capacity of the functionalized copolymers (MG-DMNPs) for EG5C-1 was about 195 mg/g, where more than 90% of the activity was recovered. Immobilized EG5C-1 exhibited improved thermal stability and increased tolerability over a broad pH range compared with the free one. Additionally, MG-DMNP/EG5C-1 biocomposite maintained approximately 80% of its initial hydrolysis productivity after five cycles of usage using filter paper as the substrate. Our results provided a promising approach for the functionalization of MNPs, enabling the immobilization of cellulases with a high loading capacity and excellent activity recovery.

18.
Phytopathology ; 114(2): 454-463, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38394356

RESUMO

Wheat sheath blight caused by the necrotic fungal pathogen Rhizoctonia cerealis is responsible for severe damage to bread wheat. Reactive oxygen species (ROS) are vital for stress resistance by plants and their homeostasis plays an important role in wheat resistance to sheath blight. Valine-glutamine (VQ) proteins play important roles in plant growth and development, and responses to biotic and abiotic stresses. However, the functional mechanism mediated by wheat VQ protein in response to sheath blight via ROS homeostasis regulation is unclear. In this study, we identified TaVQ22 protein containing the VQ motif and clarified the functional mechanisms involved in the defense of wheat against R. cerealis. TaVQ22 silencing reduced the accumulation of ROS and enhanced the resistance of wheat to R. cerealis. In addition, we showed that TaVQ22 regulated ROS generation by interacting with the WRKY transcription factor TaWRKY19-2B, thereby indicating that TaVQ22 and TaWRKY19-2B formed complexes in the plant cell nucleus. Yeast two-hybrid analysis showed that the VQ motif in TaVQ22 is crucial for the interaction, where it inhibits the transcriptional activation function of TaWRKY19-2B. In summary, TaVQ22 interacts with TaWRKY19-2B to regulate ROS homeostasis and negatively regulate the defense response to R. cerealis infection. This study provides novel insights into the mechanism that allows VQ protein to mediate the immune response in plants.


Assuntos
Doenças das Plantas , Triticum , Triticum/genética , Espécies Reativas de Oxigênio , Homeostase , Desenvolvimento Vegetal , Saccharomyces cerevisiae
19.
Plant Physiol Biochem ; 207: 108323, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38183904

RESUMO

Wheat sharp eyespot is a soil-borne disease caused by Rhizoctonia cerealis, which occurs in many countries worldwide and significantly reduces the yield. Thaumatin-like protein (TLP), also known as PR5, is a member of the pathogen response protein family and plays an essential role in plant resistance to pathogen infection. In this study, 131 TaTLP genes were identified from the wheat genome, of which 38 TaTLPs were newly discovered. The TaTLP gene family contains many tandem duplications and fragment duplications, which is a major pathway for gene amplification. Besides, we also analyzed the physicochemical properties, gene structure and promoter cis-acting regulatory elements of all the TaTLP genes. In addition, the expression patterns of nine TaTLPs in response to R. cerealis were analyzed by RT-qPCR. Six TaTLP proteins expressed in vitro had no significant inhibitory effect on R. cerealis, suggesting that these TaTLP proteins may function in other ways. Finally, we performed gene silencing of TaTLP44 in wheat, which increased the expression of some defense-associated genes and improved resistance to R. cerealis. In summary, we systematically analyzed TaTLP family members and demonstrated that TaTLP44 negatively regulates the resistance to R. cerealis by controlling expression of defense-associated genes. These results provide new insights into the functional mechanism of TaTLP proteins.


Assuntos
Basidiomycota , Triticum , Triticum/genética , Triticum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Doenças das Plantas/genética
20.
Chem Biol Drug Des ; 103(1): e14398, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38010171

RESUMO

Although there have been significant advances in cancer treatment, the urgent need to inhibit breast cancer metastasis remained unmet. Bruceine A (BA) is a natural compound extracted from Bruceae Fructus and has long been recognized to have antitumor effects with high safety and biocompatibility. However, the mechanisms and/or targets of BA for metastatic breast cancer treatment are still not fully elucidated. In this study, we systematically investigated the effects of BA on inhibition of breast cancer metastasis and its underlying mechanisms. We found that, in addition to its cytotoxic effects, BA significantly inhibited the invasion and migration capabilities of two types of breast cancer cell lines (MDA-MB-231 and MCF-7) while concurrently promoting apoptosis in these cells. Further mechanistic studies revealed that, by targeting the canonical PI3K-AKT signaling pathway, BA initiated autophagy of both types of breast cancer cell lines in vitro. In vivo results further confirmed the in vitro findings, manifested by shrinkage of size and weight of breast tumor as well as initiation of autophagy (indicated by upregulation of LC3I/II) through targeting PI3K-AKT pathway on mice model. These data collectively demonstrated the potential of BA in antimetastasis of breast cancer cells, suggesting its future clinical transformation in metastatic breast cancer therapy.


Assuntos
Neoplasias , Proteínas Proto-Oncogênicas c-akt , Quassinas , Animais , Camundongos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Proliferação de Células , Transdução de Sinais , Autofagia , Apoptose , Linhagem Celular Tumoral
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