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1.
Inorg Chem ; 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38772004

RESUMO

The accurate manipulation of the species and locations of catalytic centers is crucial for regulating the catalytic activity of catalysts, which is essential for their efficient design and development. Metal-organic frameworks (MOFs) with coordinated metal sites are ideal materials for investigating the origin of catalytic activity. In this study, we present a Ni2-MOF featuring novel Ni-based binuclear nodes with open metal sites (OMSs) and saturated metal sites (SMSs). The nickel was replaced by iron to obtain Ni1Fe1-MOF. In the electrocatalytic oxygen evolution reaction, Ni1Fe1-MOF exhibited an overpotential and Tafel slope of 370 mV@10 mA cm-2 and 87.06 mV dec-1, respectively, which were higher than those of Ni2-MOF (283 mV@10 mA cm-2 and 39.59 mV dec-1, respectively), demonstrating the superior performance of Ni1Fe1-MOF. Furthermore, theoretical calculations revealed that iron as an SMS may effectively regulate the electronic structure of the nickel catalytic center to reduce the free energy barrier ΔG*OH of the rate-determining step.

2.
Small ; : e2400410, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38721986

RESUMO

The construction of defective sites is one of the effective strategies to create high-activity Metal-Organic frameworks (MOFs) catalysts. However, traditional synthesis methods usually suffer from cumbersome synthesis steps and disordered defect structures. Herein, a cluster-cluster co-nucleation (CCCN) strategy is presented that involves the in situ introduction of size-matched functional polyoxometalates (H6P2W18O62, {P2W18}) to intervene the nucleation process of cluster-based MOFs (UiO-66), achieving one-step inducement of exposed defective sites without redundant post-processing. POM-induced UiO-66 ({P2W18}-0.1@UiO-66) exhibits a classical reo topology for well-defined cluster defects. Moreover, the defective sites and the interaction between POM and skeletal cluster nodes are directly observed by Integrated Differential Phase Contrast in Scanning Transmission Electron Microscopy (iDPC-STEM). Owing to the molecular-level proximity between defective sites and POM in the same nano-reaction space, {P2W18}-0.1@UiO-66 exhibits efficient tandem catalysis in the preparation of γ-valerolactone (γ-GVL) from laevulinic acid (LA) by the combination of Lewis and Brønsted acids with 11 times higher performance than defective UiO-66 formed by conventional coordination modulation strategy. The CCCN strategy is applicable to different POM and has the potential to be extended to other cluster-based MOFs, which will pave a new way for the construction of functional MOFs with multi-centered synergistic catalysis.

3.
Bioresour Technol ; 402: 130801, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38710419

RESUMO

The construction of aerobic denitrification (AD) systems in an antibiotic-stressed environment is a serious challenge. This study investigated strategy of cyclic stress with concentration gradient (5-30 mg/L) of sulfamethoxazole (SMX) in a sequencing batch reactor (SBR), to achieve operation of AD. Total nitrogen removal efficiency of system increased from about 10 % to 95 %. Original response of abundant-rare genera to antibiotics was changed by SMX stress, particularly conditionally rare or abundant taxa (CRAT). AD process depends on synergistic effect of heterotrophic nitrifying aerobic denitrification bacteria (Paracoccus, Thauera, Hypomicrobium, etc). AmoABC, napA, and nirK were functionally co-expressed with multiple antibiotic resistance genes (ARGs) (acrR, ereAB, and mdtO), facilitating AD process. ARGs and TCA cycling synergistically enhance the antioxidant and electron transport capacities of AD process. Antibiotic efflux pump mechanism played an important role in operation of AD. The study provides strong support for regulating activated sludge to achieve in situ AD function.

4.
Antiviral Res ; 226: 105900, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38705200

RESUMO

BACKGROUND & AIMS: The spread of foot-and-mouth disease virus (FMDV) through aerosol droplets among cloven-hoofed ungulates in close contact is a major obstacle for successful animal husbandry. Therefore, the development of suitable mucosal vaccines, especially nasal vaccines, to block the virus at the initial site of infection is crucial. PATIENTS AND METHODS: Here, we constructed eukaryotic expression plasmids containing the T and B-cell epitopes (pTB) of FMDV in tandem with the molecular mucosal adjuvant Fms-like tyrosine kinase receptor 3 ligand (Flt3 ligand, FL) (pTB-FL). Then, the constructed plasmid was electrostatically attached to mannose-modified chitosan-coated poly(lactic-co-glycolic) acid (PLGA) nanospheres (MCS-PLGA-NPs) to obtain an active nasal vaccine targeting the mannose-receptor on the surface of antigen-presenting cells (APCs). RESULTS: The MCS-PLGA-NPs loaded with pTB-FL not only induced a local mucosal immune response, but also induced a systemic immune response in mice. More importantly, the nasal vaccine afforded an 80% protection rate against a highly virulent FMDV strain (AF72) when it was subcutaneously injected into the soles of the feet of guinea pigs. CONCLUSIONS: The nasal vaccine prepared in this study can effectively induce a cross-protective immune response against the challenge with FMDV of same serotype in animals and is promising as a potential FMDV vaccine.


Assuntos
Administração Intranasal , Quitosana , Vírus da Febre Aftosa , Febre Aftosa , Nanosferas , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Vacinas Virais , Animais , Quitosana/química , Quitosana/administração & dosagem , Vírus da Febre Aftosa/imunologia , Vírus da Febre Aftosa/genética , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Febre Aftosa/prevenção & controle , Febre Aftosa/imunologia , Camundongos , Nanosferas/química , Vacinas Virais/imunologia , Vacinas Virais/administração & dosagem , Camundongos Endogâmicos BALB C , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Feminino , Ácidos Nucleicos/administração & dosagem , Imunidade nas Mucosas , Sistemas de Liberação de Medicamentos
5.
Food Funct ; 15(10): 5527-5538, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38700280

RESUMO

The salty oligopeptides from Stropharia rugosoannulata have been proven to be potential ACE inhibitors. To investigate the ACE receptor binding properties and interaction mechanisms of salty oligopeptides, the molecular interaction, dynamics simulation, and antihypertensive evaluation cross-validation strategy were employed to reveal the oligopeptides' binding reactions and modes with the ACE receptor. Single oligopeptide (ESPERPFL, KSWDDFFTR) had exothermic and specific binding reactions with the ACE receptor, driven by hydrogen bonds and van der Waals forces. The coexistence of the multiple oligopeptide molecules did not produce the apparent ACE receptor competition binding reactions. The molecular dynamics simulation verified that the two oligopeptides disturbed the ACE receptor's different residue regions. Both oligopeptides could form stable complexes with the ACE receptor. Based on the classification of 50 oligopeptides' binding modes, ESPERPFL and KSWDDFFTR belonged to different classes, and their receptor binding modes and sites complemented, resulting in a potential synergistic effect on ACE inhibition. The antihypertensive effect of KSWDDFFTR and its distribution in the body were evaluated using SHR rats orally and ICR mice by tail vein injection, and KSWDDFFTR had antihypertensive effects within 8 h. The study provides a theoretical basis for understanding salty oligopeptides' ACE receptor binding mechanism and their antihypertensive effects.


Assuntos
Anti-Hipertensivos , Simulação de Dinâmica Molecular , Oligopeptídeos , Animais , Oligopeptídeos/farmacologia , Oligopeptídeos/química , Oligopeptídeos/metabolismo , Anti-Hipertensivos/farmacologia , Anti-Hipertensivos/química , Ratos , Masculino , Peptidil Dipeptidase A/metabolismo , Peptidil Dipeptidase A/química , Agaricales/química , Agaricales/metabolismo , Camundongos , Hipertensão/tratamento farmacológico , Hipertensão/metabolismo , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Inibidores da Enzima Conversora de Angiotensina/química , Inibidores da Enzima Conversora de Angiotensina/metabolismo , Ligação Proteica , Pressão Sanguínea/efeitos dos fármacos , Ratos Endogâmicos SHR
6.
Opt Lett ; 49(9): 2237-2240, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691688

RESUMO

This Letter reports on investigations of novel, to the best of our knowledge, NiV(Ni93V7)/Ti multilayer mirrors for the operation in the wavelength region of 350-450 eV. Such mirrors are promising optical components for the Z-pinch plasma diagnostic. The NiV/Ti multilayers show superior structural and optical performance compared to conventional Ni/Ti multilayers. Replacing Ni with NiV in multilayers decreases interface widths and enhances the contrast of the refractive index between the absorber and spacer layers. The improvement of interface quality contributes to the enhancement in reflectance. Under the grazing incidence of 13°, a peak reflectivity of 25.1% at 429 eV is achieved for NiV/Ti multilayers, while 17.7% at 427 eV for Ni/Ti.

7.
J Med Chem ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38768084

RESUMO

Together with protein tyrosine kinases, protein tyrosine phosphatases (PTPs) control protein tyrosine phosphorylation and regulate numerous cellular functions. Dysregulated PTP activity is associated with the onset of multiple human diseases. Nevertheless, understanding of the physiological function and disease biology of most PTPs remains limited, largely due to the lack of PTP-specific chemical probes. In this study, starting from a well-known nonhydrolyzable phosphotyrosine (pTyr) mimetic, phosphonodifluoromethyl phenylalanine (F2Pmp), we synthesized 7 novel phosphonodifluoromethyl-containing bicyclic/tricyclic aryl derivatives with improved cell permeability and potency toward various PTPs. Furthermore, with fragment- and structure-based design strategies, we advanced compound 9 to compound 15, a first-in-class, potent, selective, and bioavailable inhibitor of human CDC14A and B phosphatases. This study demonstrates the applicability of the fragment-based design strategy in creating potent, selective, and bioavailable PTP inhibitors and provides a valuable probe for interrogating the biological roles of hCDC14 phosphatases and assessing their potential for therapeutic interventions.

8.
PLoS One ; 19(5): e0302741, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38758774

RESUMO

In the context of integrating sports and medicine domains, the urgent resolution of elderly health supervision requires effective data clustering algorithms. This paper introduces a novel higher-order hybrid clustering algorithm that combines density values and the particle swarm optimization (PSO) algorithm. Initially, the traditional PSO algorithm is enhanced by integrating the Global Evolution Dynamic Model (GEDM) into the Distribution Estimation Algorithm (EDA), constructing a weighted covariance matrix-based GEDM. This adapted PSO algorithm dynamically selects between the Global Evolution Dynamic Model and the standard PSO algorithm to update population information, significantly enhancing convergence speed while mitigating the risk of local optima entrapment. Subsequently, the higher-order hybrid clustering algorithm is formulated based on the density value and the refined PSO algorithm. The PSO clustering algorithm is adopted in the initial clustering phase, culminating in class clusters after a finite number of iterations. These clusters then undergo the application of the density peak search algorithm to identify candidate centroids. The final centroids are determined through a fusion of the initial class clusters and the identified candidate centroids. Results showcase remarkable improvements: achieving 99.13%, 82.22%, and 99.22% for F-measure, recall, and precision on dataset S1, and 75.22%, 64.0%, and 64.4% on dataset CMC. Notably, the proposed algorithm yields a 75.22%, 64.4%, and 64.6% rate on dataset S, significantly surpassing the comparative schemes' performance. Moreover, employing the text vector representation of the LDA topic vector model underscores the efficacy of the higher-order hybrid clustering algorithm in efficiently clustering text information. This innovative approach facilitates swift and accurate clustering of elderly health data from the perspective of sports and medicine integration. It enables the identification of patterns and regularities within the data, facilitating the formulation of personalized health management strategies and addressing latent health concerns among the elderly population.


Assuntos
Algoritmos , Humanos , Análise por Conglomerados , Idoso , Gestão da Informação em Saúde/métodos , Medicina Esportiva/métodos , Esportes
9.
Environ Pollut ; 350: 124034, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38663507

RESUMO

Metconazole (MEZ), a chiral triazole fungicide, produces enantioselective adverse effects in non-target organisms. Among MEZ's isomers, cis-MEZ displays robust antimicrobial properties. Evaluating MEZ and cis-MEZ's toxicity may mitigate fungicide usage and safeguard non-target organisms. Our study evaluated the toxicity of MEZ and its cis-isomers at concentrations of 0.02, 0.2, 2, and 4 mg L-1. We report stereoselectivity and severe cardiovascular defects in zebrafish, including pericardial oedema, decreased heart rate, increased sinus venous and bulbous arteries distances, intersegmental vessel defects, and altered cardiovascular development genes (hand2, gata4, nkx2.5, tbx5, vmhc, amhc, dll4, vegfaa, and vegfc). Further, MEZ significantly increased oxidative stress and apoptosis in zebrafish, primarily in the cardiac region. Isoquercetin, an antioxidant found in plants, partially mitigates MEZ-induced cardiac defects. Furthermore, MEZ upregulated the Wnt/ß-catenin pathway genes (wnt3, ß-catenin, axin2, and gsk-3ß) and ß-catenin protein expression. Inhibitor of Wnt Response-1 (IWR-1) rescued MEZ-induced cardiotoxicity. Our findings highlight oxidative stress, altered cardiovascular development genes, and upregulated Wnt/ß-catenin signaling as contributors to cardiovascular toxicity in response to MEZ and cis-MEZ treatments. Importantly, 1R,5S-MEZ exhibited greater cardiotoxicity than 1S,5R-MEZ. Thus, our study provides a comprehensive understanding of cis-MEZ's cardiovascular toxicity in aquatic life.


Assuntos
Embrião não Mamífero , Estresse Oxidativo , Via de Sinalização Wnt , Peixe-Zebra , Animais , Estresse Oxidativo/efeitos dos fármacos , Via de Sinalização Wnt/efeitos dos fármacos , Embrião não Mamífero/efeitos dos fármacos , Triazóis/toxicidade , Fungicidas Industriais/toxicidade , Coração/efeitos dos fármacos , Cardiotoxicidade/etiologia , Poluentes Químicos da Água/toxicidade
10.
J Agric Food Chem ; 72(14): 8225-8236, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38557068

RESUMO

As a continuous flow investigation of novel pesticides from natural quinolizidine alkaloids, the chemical compositions of the seeds of Sophora alopecuroides were thoroughly researched. Fifteen new aloperine-type alkaloids (1-15) as well as six known aloperine-type alkaloids (16-21) were obtained from the extract of S. alopecuroides. The structures of 1-21 were confirmed via HRESIMS, NMR, UV, IR, ECD calculations, and X-ray diffraction. The antiviral activities of 1-21 against tobacco mosaic virus (TMV) were detected following the improved method of half-leaf. Compared with ningnanmycin (protective: 69.7% and curative: 64.3%), 15 exhibited excellent protective (71.7%) and curative (64.6%) activities against TMV. Further biological studies illustrated that 15 significantly inhibited the transcription of the TMV-CP gene and increased the activities of polyphenol oxidase (PPO), peroxidase (POD), superoxide dismutase (SOD), and phenylalanine ammonia-lyase (PAL). The antifungal activities of 1-21 against Phytophythora capsica, Botrytis cinerea, Alternaria alternata, and Gibberella zeae were screened according to a mycelial inhibition test. Compound 13 displayed excellent antifungal activity against B. cinerea (EC50: 7.38 µg/mL). Moreover, in vitro antifungal mechanism studies displayed that 13 causes accumulation of reactive oxygen species and finally leads to mycelia cell membrane damage and cell death in vitro.


Assuntos
Alcaloides , Quinolizidinas , Sophora , Vírus do Mosaico do Tabaco , Antifúngicos , Sophora/química , Alcaloides/química , Antivirais/farmacologia , Antivirais/química , Sementes/química
11.
Nano Lett ; 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38687224

RESUMO

Anisotropic two-dimensional materials present a diverse range of physical characteristics, making them well-suited for applications in photonics and optoelectronics. While mechanical properties play a crucial role in determining the reliability and efficacy of 2D material-based devices, the fracture behavior of anisotropic 2D crystals remains relatively unexplored. Toward this end, we herein present the first measurement of the anisotropic fracture toughness of 2D Ta2NiSe5 by microelectromechanical system-based tensile tests. Our findings reveal a significant in-plane anisotropic ratio (∼3.0), accounting for crystal orientation-dependent crack paths. As the thickness increases, we observe an intriguing intraplanar-to-interplanar transition of fracture along the a-axis, manifesting as stepwise crack features attributed to interlayer slippage. In contrast, ruptures along the c-axis surprisingly exhibit persistent straightness and smoothness regardless of thickness, owing to the robust interlayer shear resistance. Our work affords a promising avenue for the construction of future electronics based on nanoribbons with atomically sharp edges.

12.
Hepatobiliary Surg Nutr ; 13(2): 198-213, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38617471

RESUMO

Background: Adequate evaluation of degrees of liver cirrhosis is essential in surgical treatment of hepatocellular carcinoma (HCC) patients. The impact of the degrees of cirrhosis on prediction of post-hepatectomy liver failure (PHLF) remains poorly defined. This study aimed to construct and validate a combined pre- and intra-operative nomogram based on the degrees of cirrhosis in predicting PHLF in HCC patients using prospective multi-center's data. Methods: Consecutive HCC patients who underwent hepatectomy between May 18, 2019 and Dec 19, 2020 were enrolled at five tertiary hospitals. Preoperative cirrhotic severity scoring (CSS) and intra-operative direct liver stiffness measurement (DSM) were performed to correlate with the Laennec histopathological grading system. The performances of the pre-operative nomogram and combined pre- and intra-operative nomogram in predicting PHLF were compared with conventional predictive models of PHLF. Results: For 327 patients in this study, histopathological studies showed the rates of HCC patients with no, mild, moderate, and severe cirrhosis were 41.9%, 29.1%, 22.9%, and 6.1%, respectively. Either CSS or DSM was closely correlated with histopathological stages of cirrhosis. Thirty-three (10.1%) patients developed PHLF. The 30- and 90-day mortality rates were 0.9%. Multivariate regression analysis showed four pre-operative variables [HBV-DNA level, ICG-R15, prothrombin time (PT), and CSS], and one intra-operative variable (DSM) to be independent risk factors of PHLF. The pre-operative nomogram was constructed based on these four pre-operative variables together with total bilirubin. The combined pre- and intra-operative nomogram was constructed by adding the intra-operative DSM. The pre-operative nomogram was better than the conventional models in predicting PHLF. The prediction was further improved with the combined pre- and intra-operative nomogram. Conclusions: The combined pre- and intra-operative nomogram further improved prediction of PHLF when compared with the pre-operative nomogram. Trial Registration: Clinicaltrials.gov Identifier: NCT04076631.

13.
Tetrahedron ; 1562024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38618612

RESUMO

Natural products have been playing indispensable roles in the development of lifesaving drug molecules. They are also valuable sources for covalent protein modifiers. However, they often are scarce in nature and have complex chemical structures, which are limiting their further biomedical development. Thus, natural product-inspired small molecules which still contain the essence of the parent natural products but are readily available and amenable for structural modification, are important and desirable in searching for lead compounds for various disease treatment. Inspired by the complex and diverse ent-kaurene diterpenoids with significant biological activities, we have created a synthetically accessible and focused covalent library by incorporating the bicyclo[3.2.1]octane α-methylene ketone, which is considered as the pharmacophore of ent-kaurene diterpenoids, as half of the structure, and replacing the other half with much less complex but more druglike scaffolds. From this library, we have identified and characterized selective covalent inhibitors of protein tyrosine phosphatase SHP2, an important anti-cancer therapeutic target. The success of this study demonstrated the importance of creating and evaluating natural product-inspired library as well as their application in targeting challenging disease targets.

14.
Sci Adv ; 10(14): eadj9305, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38569042

RESUMO

The power and scope of disease modeling can be markedly enhanced through the incorporation of broad genetic diversity. The introduction of pathogenic mutations into a single inbred mouse strain sometimes fails to mimic human disease. We describe a cross-species precision disease modeling platform that exploits mouse genetic diversity to bridge cell-based modeling with whole organism analysis. We developed a universal protocol that permitted robust and reproducible neural differentiation of genetically diverse human and mouse pluripotent stem cell lines and then carried out a proof-of-concept study of the neurodevelopmental gene DYRK1A. Results in vitro reliably predicted the effects of genetic background on Dyrk1a loss-of-function phenotypes in vivo. Transcriptomic comparison of responsive and unresponsive strains identified molecular pathways conferring sensitivity or resilience to Dyrk1a1A loss and highlighted differential messenger RNA isoform usage as an important determinant of response. This cross-species strategy provides a powerful tool in the functional analysis of candidate disease variants identified through human genetic studies.


Assuntos
Células-Tronco Pluripotentes , Animais , Camundongos , Humanos , Fenótipo
16.
Pestic Biochem Physiol ; 200: 105811, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38582583

RESUMO

Aedes albopictus can transmit several lethal arboviruses. This mosquito has become a sever public health threat due to its rapidly changing global distribution. Chitin, which is the major component of the cuticle and peritrophic membrane (PM), is crucial for the growth and development of insect. microRNAs (miRNAs) play important roles in the posttranscriptional level regulation of gene expression, thereby influencing many biological processes in insects. In this study, an attempt was made to evaluate the role of miR-306-5p in regulating chitin metabolism in Ae. albopictus pupae. Overexpression of miR-306-5p resulted in a significantly reduced survival rate in pupae and an increased malformation rate in adults. Both in vivo and in vitro evidence confirmed the presence of the competing endogenous RNA (ceRNA) regulatory axis (linc8338-miR-306-5p-XM_019678125.2). RNAi of linc8338 and XM_019678125.2 had effects on pupae similar to those of miR-306-5p. The highest expression level of miR-306-5p was found in the midgut, and alteration in the expression of miR-306-5p, XM_019678125.2 and linc8338 induced increased transcript levels of chitin synthase 2 (AaCHS2) and decreased chitinase 10 (AaCht10); as well as increased thickness of the midgut and enlarged midgut epithelial cells. The results of this study highlight the potential of miR-306-5p as a prospective target in mosquito control and confirm that the ceRNA mechanism is involved in chitin metabolism. These findings will provide a basis for further studies to uncover the molecular mechanisms through which ncRNAs regulate chitin metabolism.


Assuntos
Aedes , MicroRNAs , Animais , Pupa/genética , MicroRNAs/genética , Aedes/metabolismo , Quitina
17.
Expert Opin Ther Targets ; 28(4): 259-271, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38653737

RESUMO

INTRODUCTION: Phosphatase of regenerating liver (PRL) family proteins, also known as protein tyrosine phosphatase 4A (PTP4A), have been implicated in many types of cancers. The PRL family of phosphatases consists of three members, PRL1, PRL2, and PRL3. PRLs have been shown to harbor oncogenic potentials and are highly expressed in a variety of cancers. Given their roles in cancer progression and metastasis, PRLs are potential targets for anticancer therapies. However, additional studies are needed to be performed to fully understand the roles of PRLs in blood cancers. AREAS COVERED: In this review, we will summarize recent studies of PRLs in normal and malignant hematopoiesis, the role of PRLs in regulating various signaling pathways, and the therapeutic potentials of targeting PRLs in hematological malignancies. We will also discuss how to improve current PRL inhibitors for cancer treatment. EXPERT OPINION: Although PRL inhibitors show promising therapeutic effects in preclinical studies of different types of cancers, moving PRL inhibitors from bench to bedside is still challenging. More potent and selective PRL inhibitors are needed to target PRLs in hematological malignancies and improve treatment outcomes.


Assuntos
Antineoplásicos , Neoplasias Hematológicas , Terapia de Alvo Molecular , Proteínas Tirosina Fosfatases , Transdução de Sinais , Humanos , Proteínas Tirosina Fosfatases/antagonistas & inibidores , Proteínas Tirosina Fosfatases/metabolismo , Neoplasias Hematológicas/tratamento farmacológico , Animais , Antineoplásicos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/metabolismo , Desenvolvimento de Medicamentos , Proteínas de Membrana , Proteínas de Ciclo Celular
18.
Transplantation ; 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38685203

RESUMO

BACKGROUND: This study aimed to investigate the cardioprotective effect of exosomes derived from human umbilical cord mesenchymal stem cells on donation after circulatory death (DCD) hearts preserved with normothermic ex vivo heart perfusion (EVHP) in a rat heart transplantation model. METHODS: Thirty-two male Lewis rats were divided into 2 groups: the control group and the exosome group. The donor-heart rats were subjected to the DCD procedure by suffering a 15-min warm ischemia injury, subsequently preserved with EVHP for 90 min, and then transplanted into recipients via abdominal heterotopic heart transplantation. Vehicle or exosome was added into the perfusate of normothermic EVHP in the control or exosome group. We evaluated left ventricular graft function, myocardial inflammation, and myocardial apoptosis of the donor heart 1.5 h after heart transplantation. Furthermore, we investigate the alternation of myocardial gene expression in the donor hearts between both groups by transcriptome sequencing. RESULTS: The treatment with exosome significantly enhanced cardiac function through increasing left ventricular developed pressure, dp/dtmax, and dp/dtmin of DCD hearts at 90 min after heart transplantation compared with the control group. The myocardial cells in the exosome group exhibited an orderly arrangement without obvious edema. Furthermore, exosome added into perfusate in the exosome group significantly attenuated the level of inflammatory response and apoptosis. Transcriptome sequencing and RT-qPCR showed the phosphoinositide 3-kinase/protein kinase B pathway was activated after exosome treatment. CONCLUSIONS: Normothermic EVHP combined with exosome can be a promising and novel DCD heart preservation strategy, alleviating myocardial ischemia-reperfusion injury in the DCD heart.

19.
PLoS One ; 19(3): e0299541, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38551930

RESUMO

The activities of the phospholipase C gamma (PLCγ) 1 and 2 enzymes are essential for numerous cellular processes. Unsurprisingly, dysregulation of PLCγ1 or PLCγ2 activity is associated with multiple maladies including immune disorders, cancers, and neurodegenerative diseases. Therefore, the modulation of either of these two enzymes has been suggested as a therapeutic strategy to combat these diseases. To aid in the discovery of PLCγ family enzyme modulators that could be developed into therapeutic agents, we have synthesized a high-throughput screening-amenable micellular fluorogenic substrate called C16CF3-coumarin. Herein, the ability of PLCγ1 and PLCγ2 to enzymatically process C16CF3-coumarin was confirmed, the micellular assay conditions were optimized, and the kinetics of the reaction were determined. A proof-of-principle pilot screen of the Library of Pharmacologically Active Compounds 1280 (LOPAC1280) was performed. This new substrate allows for an additional screening methodology to identify modulators of the PLCγ family of enzymes.


Assuntos
Corantes Fluorescentes , Fosfatidilinositóis , Fosfolipase C gama , Diester Fosfórico Hidrolases , Cumarínicos/farmacologia , Fosfolipases Tipo C
20.
J Am Chem Soc ; 146(12): 8425-8434, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38488481

RESUMO

The precise design of catalytic metal centers with multiple chemical states to facilitate sophisticated reactions involving multimolecular activation is highly desirable but challenging. Herein, we report an ordered macroporous catalyst with heterovalent metal pair (HMP) sites comprising CuII-CuI on the basis of a microporous metal-organic framework (MOF) system. This macroporous HMP catalyst with proximity heterovalent dual copper sites, whose distance is controlled to ∼2.6 Å, on macropore surface exhibits a co-activation behavior of ethanol at CuII and alkyne at CuI, and avoids microporous restriction, thereby promoting additive-free alkyne hydroboration reaction. The desired yield enhances dramatically compared with the pristine MOF and ordered macroporous MOF both with solely isovalent CuII-CuII sites. Density functional theory calculations reveal that the Cu-HMP sites can stabilize the Bpin-CuII-CuI-alkyne intermediate and facilitate C-B bond formation, resulting in a smooth alkyne hydroboration process. This work provides new perspectives to design multimolecular activation catalysts for sophisticated matter transformations.

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