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1.
IUBMB Life ; 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39082886

RESUMO

Parkinson's disease (PD) is a degenerative disorder of the nervous system characterized by the loss of dopaminergic neurons and damage of neurons in the substantia nigra (SN) and striatum, resulting in impaired motor functions. This study aims to investigate how extracellular vesicles (EVs) derived from human umbilical cord mesenchymal stem cells (HucMSC) regulate Special AT-rich sequence-binding protein-1 (SATB 1) and influence Wnt/ß-catenin pathway and autophagy in PD model. The PD model was induced by damaging SH-SY5Y cells and mice using 6-OHDA. According to the study, administering EVs every other day for 14 days improved the motor behavior of 6-OHDA-induced PD mice and reduced neuronal damage, including dopaminergic neurons. Treatment with EVs for 12 hours increased the viability of 6-OHDA-induced SH-SY5Y cells. The upregulation of SATB 1 expression with EV treatment resulted in the activation of the Wnt/ß-catenin pathway in PD model and led to overexpression of ß-catenin. Meanwhile, the expression of LC3 II was decreased, indicating alterations in autophagy. In conclusion, EVs could mitigate neuronal damage in the 6-OHDA-induced PD model by upregulating SATB 1 and activating Wnt/ß-catenin pathway while also regulating autophagy. Further studies on the potential therapeutic applications of EVs for PD could offer new insights and strategies.

2.
BMC Cardiovasc Disord ; 24(1): 175, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38515032

RESUMO

BACKGROUND: Approximately 90% of intracardial thrombi originate from the left atrial appendage in non-valvular atrial fibrillation patients. Even with anticoagulant therapy, left atrial appendage thrombus (LAAT) still occurs in 8% of patients. While left atrial appendage closure (LAAC) could be a promising alternative, the current consensus considers LAAT a contraindication to LAAC. However, the feasibility and safety of LAAC in patients with LAAT have yet to be determined. METHODS: This systematic review synthesizes published data to explore the feasibility and safety of LAAC for patients with LAAT. RESULTS: This study included a total of 136 patients with LAATs who underwent successful LAAC. The Amulet Amplatzer device was the most frequently utilized device (48.5%). Among these patients, 77 (56.6%) had absolute contraindications to anticoagulation therapy. Cerebral protection devices were utilized by 47 patients (34.6%). Transesophageal echocardiography (TEE) is the primary imaging technique used during the procedure. Warfarin and novel oral anticoagulants were the main anticoagulant medications used prior to the procedure, while dual antiplatelet therapy was primarily used post-procedure. During a mean follow-up period of 13.2 ± 11.5 months, there was 1 case of fatality, 1 case of stroke, 3 major bleeding events, 3 instances of device-related thrombus, and 8 cases of peri-device leakage. CONCLUSIONS: This review highlights the preliminary effectiveness and safety of the LAAC procedure in patients with persistent LAAT. Future large-scale RCTs with varied LAAT characteristics and LAAC device types are essential for evidence-based decision-making in clinical practice.


Assuntos
Anticoagulantes , Apêndice Atrial , Fibrilação Atrial , Oclusão do Apêndice Atrial Esquerdo , Trombose , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Anticoagulantes/uso terapêutico , Anticoagulantes/efeitos adversos , Anticoagulantes/administração & dosagem , Apêndice Atrial/diagnóstico por imagem , Apêndice Atrial/fisiopatologia , Fibrilação Atrial/complicações , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Contraindicações de Medicamentos , Ecocardiografia Transesofagiana , Cardiopatias/diagnóstico por imagem , Oclusão do Apêndice Atrial Esquerdo/efeitos adversos , Oclusão do Apêndice Atrial Esquerdo/instrumentação , Medição de Risco , Fatores de Risco , Dispositivo para Oclusão Septal , Trombose/diagnóstico por imagem , Trombose/etiologia , Trombose/cirurgia , Resultado do Tratamento
3.
J Nat Prod ; 87(7): 1786-1797, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-38986603

RESUMO

Carabranolides present characteristic NMR resonances for the cyclopropane moiety, which distinctly differ from those of other compounds and were used for an NMR-guided isolation in this study. As a result, 11 undescribed carabranolides (1-11), along with five known ones (12-16), were isolated from the fruits of Carpesium abrotanoides L. Compounds 1-11 are new esters of carabrol at C-4 with different carboxylic acids. Their structures were elucidated by HRESIMS and NMR spectroscopic data analysis. The biological evaluation showed that compounds 2-4, 15, and 16 exhibited significant inhibitory activity against LPS-induced NO release with an IC50 value of 5.6-9.1 µM and dose-dependently decreased iNOS protein expression in RAW264.7 cells.


Assuntos
Anti-Inflamatórios , Asteraceae , Frutas , Óxido Nítrico , Animais , Camundongos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Asteraceae/química , Frutas/química , Lipopolissacarídeos/farmacologia , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Óxido Nítrico/biossíntese , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Células RAW 264.7 , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia
4.
Mar Drugs ; 22(7)2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-39057405

RESUMO

Traditional isolation methods often lead to the rediscovery of known natural products. In contrast, genome mining strategies are considered effective for the continual discovery of new natural products. In this study, we discovered a unique prenyltransferase (PT) through genome mining, capable of catalyzing the transfer of a prenyl group to an aromatic nucleus to form C-C or C-O bonds. A pair of new hydroxyphenylacetic acid derivative enantiomers with prenyl units, (±)-peniprenydiol A (1), along with 16 known compounds (2-17), were isolated from a marine fungus, Penicillium sp. W21C371. The separation of 1 using chiral HPLC led to the isolation of the enantiomers 1a and 1b. Their structures were established on the basis of extensive spectroscopic analysis, including 1D, 2D NMR and HRESIMS. The absolute configurations of the new compounds were determined by a modified Mosher method. A plausible biosynthetic pathway for 1 was deduced, facilitated by PT catalysis. In the in vitro assay, 2 and 3 showed promising inhibitory activity against Escherichia coli ß-glucuronidase (EcGUS), with IC50 values of 44.60 ± 0.84 µM and 21.60 ± 0.76 µM, respectively, compared to the positive control, D-saccharic acid 1,4-lactone hydrate (DSL). This study demonstrates the advantages of genome mining in the rational acquisition of new natural products.


Assuntos
Dimetilaliltranstransferase , Penicillium , Organismos Aquáticos/química , Produtos Biológicos/farmacologia , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Dimetilaliltranstransferase/metabolismo , Dimetilaliltranstransferase/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Penicillium/química , Fenilacetatos/farmacologia , Fenilacetatos/química , Fenilacetatos/isolamento & purificação , Estereoisomerismo
5.
Molecules ; 28(9)2023 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-37175232

RESUMO

α-Glucosidase (AGS) inhibitors have been regarded as an ideal target for the management of type 2 diabetes mellitus (T2DM) since they can maintain an acceptable blood glucose level by delaying the digestion of carbohydrates and diminishing the absorption of monosaccharides. In the process of our endeavor in mining AGS inhibitors from natural sources, the culture broth of two mangrove-derived actinomycetes Streptomyces sp. WHUA03267 and Streptomyces sp. WHUA03072 exhibited an apparent inhibitory activity against AGS. A subsequent chemical investigation into the two extracts furnished 28 secondary metabolites that were identified by spectroscopic methods as two previously undescribed linear polyketides 1-2, four benzenoid ansamycins 3-6, fourteen cyclodipeptides 7-18, one prenylated indole derivative 19, two fusicoccane-type diterpenoids 20-21, two hydroxamate siderophore 22-23, and five others 24-28. Among all of the isolates, 11 and 24 were obtained from actinomycetes for the first time, while 20-21 had never been reported to occur in a marine-derived microorganism previously. In the in vitro AGS inhibitory assay, compounds 3, 8, 9, 11, 14, 16, and 17 exhibited potent to moderate activity with IC50 values ranging from 35.76 ± 0.40 to 164.5 ± 15.5 µM, as compared with acarbose (IC50 = 422.3 ± 8.4 µM). The AGS inhibitory activity of 3, 9, 14, 16, and 17 was reported for the first time. In particular, autolytimycin (3) represented the first ansamycin derivative reported to possess the AGS inhibitory activity. Kinetics analysis and molecular docking were performed to determine the inhibition types and binding modes of these inhibitors, respectively. In the MTT assay, 3, 8, 9, 11, 14, 16, and 17 exhibited no apparent cytotoxicity to the human normal hepatocyte (LO2) cells, suggesting satisfactory safety of these AGS inhibitors.


Assuntos
Actinobacteria , Diabetes Mellitus Tipo 2 , Streptomyces , Humanos , Inibidores de Glicosídeo Hidrolases/química , Actinobacteria/metabolismo , Actinomyces/metabolismo , Simulação de Acoplamento Molecular , Streptomyces/metabolismo , alfa-Glucosidases/metabolismo , Estrutura Molecular
6.
BMC Surg ; 22(1): 284, 2022 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-35871659

RESUMO

BACKGROUND: The superiorities in proximal facet joint protection of robot-assisted (RA) pedicle screw placement and screw implantation via the cortical bone trajectory (CBT) have rarely been compared. Moreover, findings on the screw accuracy of both techniques are inconsistent. Therefore, we analyzed the screw accuracy and incidence of facet joint violation (FJV) of RA and CBT screw insertion in the same study and compared them with those of conventional pedicle screw (PS) insertion. The possible factors affecting screw accuracy and FJV were also analyzed. METHODS: A total of 166 patients with lumbar degenerative diseases requiring posterior L4-5 fusion were retrospectively included and divided into the RA, PS, and CBT groups from March 2019 to December 2021. The grades of intrapedicular accuracy and superior FJV were evaluated according to the Gertzbin-Robbins scale and the Babu scale based on postoperative CT. Univariable and multivariable analyses were conducted to assess the possible risk factors associated with intrapedicular accuracy and superior FJV. RESULTS: The rates of optimal screw insertion in the RA, PS, and CBT groups were 87.3%, 81.3%, and 76.5%, respectively. The difference between the RA and CBT groups was statistically significant (P = 0.004). Superior FJVs occurred in 28.2% of screws in RA, 45.0% in PS, and 21.6% in CBT. The RA and CBT groups had fewer superior FJVs than the PS group (P = 0.008 and P < 0.001, respectively), and no significant difference was observed between the RA and CBT groups (P = 0.267). Multivariable analysis revealed that the CBT technique was an independent risk factor for intrapedicular accuracy. Furthermore, older age, the conventional PS technique and a smaller facet angle were independently associated with the incidence of superior FJVs. CONCLUSIONS: The RA and CBT techniques were associated with fewer proximal FJVs than the PS technique. The RA technique showed a higher rate of intrapedicular accuracy than the CBT technique. The CBT technique was independently associated with screw inaccuracy. Older age, conventional PS technique and coronal orientation of the facet join were independent risk factors for superior FJV.


Assuntos
Parafusos Pediculares , Robótica , Fusão Vertebral , Osso Cortical/cirurgia , Humanos , Vértebras Lombares/cirurgia , Parafusos Pediculares/efeitos adversos , Estudos Retrospectivos , Fusão Vertebral/métodos
7.
Zhongguo Zhong Yao Za Zhi ; 45(2): 347-351, 2020 Jan.
Artigo em Zh | MEDLINE | ID: mdl-32237317

RESUMO

Eight compounds were isolated from the ethyl acetate extraction of Prunus mume by column chromatography. On the basis of physicochemical properties and spectrum analysis, these compounds were identified as isoquercitrin-6″-O-benzoate(1), pinoresinol(2), naringin(3), ethyl-ß-D-glucopyranoside(4), astragalin(5), quercetin(6), hypericin(7), and rutin(8). Among them, compound 1 was a new natural product, and compounds 2-5 were isolated from this plant for the first time. In vitro study, compounds 1, 3, 5-8 could significantly increase the cell survival ratio.


Assuntos
Compostos Fitoquímicos/análise , Extratos Vegetais/química , Prunus/química , Acetatos , Solventes
8.
Chemistry ; 25(19): 5005-5013, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30848015

RESUMO

The development of energy devices based on iron oxides/hydroxides is largely hindered by their poor conductivity and large volume changes, especially with regard to specific capacitance and cycle stability. Herein, superior capacitance (1575 F g-1 at 1.25 A g-1 ) and high rate performance (955 F g-1 at 25 A g-1 ) were realized by synthesizing sub-nanometer, ultrafine α-Fe2 O3 sheets loaded on graphene (SU-Fe2 O3 -rGO). An assembled asymmetric supercapacitor showed outstanding cycle stability (106 % retention after 30 000 cycles). This excellent performance arises from the unique structural characteristics of the α-Fe2 O3 sheets, which not only enrich electrochemically reactive sites, but also largely eliminate the volume changes after long-term charge/discharge cycling. The synthesis of SU-Fe2 O3 -rGO critically depends on control of the crystallization kinetics during growth. A controlled heterogeneous nucleation mechanism results in the formation of atomically thin α-Fe2 O3 sheets on graphene rather than large particles in solvent, as clarified by theoretical calculations. This strategy paves a new way to synthesizing atomically thin transition metal oxide sheets and low-cost, eco-friendly iron-based energy storage.

9.
Molecules ; 24(12)2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-31208101

RESUMO

A chemical investigation of the fibrous roots of Anemarrhena asphodeloides Bge. led to the isolation of four benzophenones, including one new compound (1) and three known ones (2-4). Comprehensive 1D, 2D NMR and HRESIMS data established the structures of the isolated compounds. The absolute configurations were determined by comparison of the calculated optical rotation (OR) with experimental data. All the isolates were evaluated for their cytotoxicities on hepatocellular carcinoma cell lines (HepG2 and Hep3B). Compound 1 showed strong cytotoxicity against HepG2 and Hep3B cells, with IC50 values at 153.1 and 180.6 nM. Through MTT assay, flow cytometry and Western blot analysis, compound 1 demonstrated the ability to stimulate apoptosis via the NF-κB signaling pathway in HepG2 cells. These benzophenones are potential lead compounds for the development of better treatments for hepatocellular carcinoma.


Assuntos
Anemarrhena/química , Antineoplásicos Fitogênicos/farmacologia , Benzofenonas/farmacologia , Extratos Vegetais/farmacologia , Antineoplásicos Fitogênicos/química , Apoptose/efeitos dos fármacos , Benzofenonas/química , Sobrevivência Celular/efeitos dos fármacos , Células Hep G2 , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , NF-kappa B/metabolismo , Extratos Vegetais/química , Raízes de Plantas/química , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-Atividade
10.
Ecotoxicol Environ Saf ; 138: 146-153, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28043033

RESUMO

Quantitative predictions of metal-metal interactions and toxicity in aquatic organisms meet a unique challenge. Accumulation and toxicity of Cu and Zn mixtures in zebrafish larvae has been quantified in binary metal system with variable combinatorial concentrations in order to understand the interactions between essential trace metals and assess availability of the toxicokinetic-toxicodynamic (TK-TD) model which simulated the uptake of metals over time as well as metal toxicity after 24h of exposure. Competitive uptake experiments showed a straightforward antagonistic competition, as would be predicted by Michaelis-Menten competitive equilibrium model. Zn uptake decreased significantly in the presence of Cu2+ concentrations higher than 10-6M. Cu2+ was shown to compete strongly with Zn for uptake, having a higher affinity constant to biotic ligand (BL) sites (KCuBL=105.42M-1) than Zn (KZnBL=104.13M-1). TK-TD model considering potential metal-metal antagonism interactions showed good predictive power in predicting accumulation and toxicity of Cu-Zn mixtures in zebrafish larvae with the high coefficient of determination (r2) and significant level (p). In particular, with the elevated Zn concentrations in mixtures, the TD model showed better predictive power in predicting toxicity of 10-6M Cu concentration in Cu-Zn mixtures. The TK-TD analysis provided some new insights into the interactive mechanism of binary Cu and Zn exposure in aquatic animals and may have important implications for our understanding of quantitative predictions of metal-metal interactions and toxicity in a field where animals are simultaneously exposed to several metals.


Assuntos
Cobre/toxicidade , Larva/efeitos dos fármacos , Modelos Biológicos , Peixe-Zebra , Zinco/toxicidade , Animais , Cobre/metabolismo , Cobre/farmacocinética , Zinco/metabolismo , Zinco/farmacocinética
12.
Med Sci Monit ; 21: 144-52, 2015 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-25579245

RESUMO

BACKGROUND: The appropriate treatment of non-small cell lung cancer (NSCLC) with single brain metastasis (SBM) is still controversial. A systematic review was designed to evaluate the effectiveness of neurosurgery and stereotactic radiosurgery (SRS) in patients with SBM from NSCLC. MATERIAL/METHODS: PUBMED, EMBASE, the Cochrane Library, Web of Knowledge, Current Controlled Trials, Clinical Trials, and 2 conference websites were searched to select NSCLC patients with only SBM who received brain surgery or SRS. SPSS 18.0 software was used to analyze the mean median survival time (MST) and Stata 11.0 software was used to calculate the overall survival (OS). RESULTS: A total of 18 trials including 713 patients were systematically reviewed. The MST of the patients was 12.7 months in surgery group and 14.85 months in SRS group, respectively. The 1, 2, and 5 years OS of the patients were 59%, 33%, and 19% in surgery group, and 62%, 33%, and 14% in SRS group, respectively. Furthermore, in the surgery group, the 1 and 3 years OS were 68% and 15% in patients with controlled primary tumors, and 50% and 13% in the other patients with uncontrolled primary tumors, respectively. Interestingly, the 5-year OS was up to 21% in patients with controlled primary tumors. CONCLUSIONS: There was no significant difference in MST or OS between patients treated with neurosurgery and SRS. Patients with resectable lung tumors and SBM may benefit from the resection of both primary lesions and metastasis.


Assuntos
Neoplasias Encefálicas/secundário , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Radiocirurgia , Neoplasias Encefálicas/cirurgia , Carcinoma/patologia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Craniotomia , Humanos , Neoplasias Pulmonares/cirurgia , Imageamento por Ressonância Magnética , Metástase Neoplásica , Estudos Observacionais como Assunto , Prognóstico , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Resultado do Tratamento
13.
Heliyon ; 10(6): e27986, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38515657

RESUMO

In allusion to solve the issue of fault diagnosis for bearing and other rotatory machinery, a technique based on fined-grained multi-scale Kolmogorov entropy and whale optimized multi-class support vector machine (abbreviated as FGMKE-WOA-MSVM) is proposed. Firstly, vibration signals are decomposed by fine-grained multi-scale decomposition, and the Kolmogorov entropy of the sub-signals at different analysis scales is calculated as the multi-dimension feature vector, which quantitatively characterize the complexity of the signal at multi-scales. Aiming at the problem of sensitive parameters selection for multi-class support vector machine model (abbreviated as MSVM), the whale optimization algorithm (abbreviated as WOA) is introduced to optimize the penalty factor and kernel function parameter, and constructing optimal WOA-MSVM model. Finally, an instance analysis is carried out with Jiangnan University bearing datasets to verify the effectiveness and superiority of this technique. The results show that compared with different feature vectors and models such as K nearest neighbors (abbreviated as KNN) and Decision Tree (abbreviated as RF), the proposed technique is superior with fast computation speed and high diagnostic efficiency.

14.
Am J Cardiovasc Drugs ; 24(3): 329-342, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38568400

RESUMO

The delayed titration of guideline-directed drug therapy (GDMT) is a complex event influenced by multiple factors that often result in poor prognosis for patients with heart failure (HF). Individualized adjustments in GDMT titration may be necessary based on patient characteristics, and every clinician is responsible for promptly initiating GDMT and titrating it appropriately within the patient's tolerance range. This review examines the current challenges in GDMT implementation and scrutinizes titration considerations within distinct subsets of HF patients, with the overarching goal of enhancing the adoption and effectiveness of GDMT. The authors also underscore the significance of establishing a novel management strategy that integrates cardiologists, nurse practitioners, pharmacists, and patients as a unified team that can contribute to the improved promotion and implementation of GDMT.


Assuntos
Insuficiência Cardíaca , Guias de Prática Clínica como Assunto , Humanos , Insuficiência Cardíaca/tratamento farmacológico
15.
ACS Biomater Sci Eng ; 10(5): 3069-3085, 2024 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-38578110

RESUMO

Parkinson's disease (PD) is the second most common neurodegenerative disorder worldwide. Drug delivery to the brain through the blood-brain barrier (BBB) is a significant challenge in PD treatment. Exosomes, which can efficiently traverse the BBB, which many drugs cannot penetrate, are ideal natural carriers for drug delivery. In this study, the BBB shuttle peptide was modified on the exosome surfaces. Three types of exosomes were constructed, each modified with a distinct peptide (RVG29, TAT, or Ang2) and loaded with miR-133b. The safety and brain-targeting capabilities of these peptide-modified exosomes were then evaluated. Finally, the mechanism by which RVG29-Exo-133b regulates the RhoA-ROCK signaling pathway was investigated. The findings indicate that the three peptide-modified exosomes were adequately tolerated, safe, and effectively assimilated in vivo and ex vivo, with RVG29 exhibiting superior targeting to the brain. Furthermore, RVG29-Exo-133b decreased the phosphorylation level of the Tau protein by targeting the RhoA-ROCK signaling pathway. It also enhanced the motor function in mice with PD, thereby reducing the degree of depression, improving dopaminergic neuron function, and attenuating 6-OHDA-induced nerve damage. In this study, we developed a stable drug delivery mechanism that targets the intracerebral region using exosomes. Furthermore, a novel strategy was developed to manage PD and can potentially serve as a preclinical basis for utilizing exosomes in the diagnosis and treatment of neurodegenerative conditions.


Assuntos
Exossomos , MicroRNAs , Doença de Parkinson , Transdução de Sinais , Quinases Associadas a rho , Proteína rhoA de Ligação ao GTP , Exossomos/metabolismo , Animais , Quinases Associadas a rho/metabolismo , Quinases Associadas a rho/genética , MicroRNAs/metabolismo , MicroRNAs/genética , Doença de Parkinson/metabolismo , Doença de Parkinson/genética , Proteína rhoA de Ligação ao GTP/metabolismo , Proteína rhoA de Ligação ao GTP/genética , Camundongos , Masculino , Camundongos Endogâmicos C57BL , Humanos , Peptídeos/metabolismo , Barreira Hematoencefálica/metabolismo
16.
Int J Cardiol ; 407: 131985, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38513736

RESUMO

Radiofrequency ablation (RFA) has been a central therapeutic strategy for ventricular tachycardia (VT). However, concerns about its long-term effectiveness and complications have arisen. Pulsed field ablation (PFA), characterized by its nonthermal, highly tissue-selective ablation technique, has emerged as a promising alternative. This comprehensive review delves into the potential advantages and opportunities presented by PFA in the realm of VT, drawing insights from both animal experimentation and clinical case studies. PFA shows promise in generating superior lesions within scarred myocardial tissue, and its inherent repetition dependency holds the potential to enhance therapeutic outcomes. Clinical cases underscore the promise of PFA for VT ablation. Despite its promising applications, challenges such as catheter maneuverability and proarrhythmic effects require further investigation. Large-scale, long-term studies are essential to establish the suitability of PFA for VT treatment.


Assuntos
Ablação por Cateter , Taquicardia Ventricular , Taquicardia Ventricular/cirurgia , Taquicardia Ventricular/fisiopatologia , Taquicardia Ventricular/terapia , Humanos , Ablação por Cateter/métodos , Animais , Resultado do Tratamento
17.
Int J Nanomedicine ; 19: 4923-4939, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38828201

RESUMO

Purpose: In recent years, exosomes have been proved to be used to treat many diseases. However, due to the lack of uniform quality control standards for exosomes, the safety of exosomes is still a problem to be solved, especially now more and more exosomes are used in clinical trials, and its non-clinical safety evaluation is particularly important. However, there is no safety evaluation standard for exosomes at present. Therefore, this study will refer to the evaluation criteria of therapeutic biological products, adopt non-human primates to evaluate the non-clinical safety of human umbilical cord mesenchymal stem cell exosomes from the general pharmacology and immunotoxicity, aiming at establishing a safety evaluation system of exosomes and providing reference for the clinical application of exosomes in the future. Methods: 3.85 × 1012 exosomes derived from human umbilical cord mesenchymal stem cells were injected into cynomolgus monkeys intravenously. The changes of general clinical conditions, hematology, immunoglobulin, Th1/Th2 cytokines, T lymphocytes and B lymphocytes, and immune organs were observed before and within 14 days after injection. Results: The results showed that exosomes did not have obvious pathological effects on the general clinical conditions, blood, coagulation function, organ coefficient, immunoglobulin, Th1/Th2 cytokines, lymphocytes, major organs, and major immune organs (spleen, thymus, bone marrow) of cynomolgus monkeys. However, the number of granulocyte-macrophage colonies in exosomes group was significantly higher than that in control group. Conclusion: To sum up, the general pharmacological results and immunotoxicity results showed that the injection of 3.85 × 1012 exosomes may have no obvious adverse reactions to cynomolgus monkeys. This dose of exosomes is relatively safe for treatment, which provides basis research for non-clinical safety evaluation of exosomes and provides reliable research basis for future clinical application of exosomes.


Assuntos
Exossomos , Macaca fascicularis , Células-Tronco Mesenquimais , Cordão Umbilical , Animais , Exossomos/química , Células-Tronco Mesenquimais/citologia , Humanos , Cordão Umbilical/citologia , Masculino , Feminino , Citocinas/metabolismo
18.
ISA Trans ; 139: 24-34, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37005206

RESUMO

In this study, an observer-based model predictive control (MPC) algorithm is addressed for an uncertain discrete-time nonlinear networked control system (NCS) subject to hybrid malicious attacks by using interval type-2 Takagi-Sugeno (IT2 T-S) fuzzy theory. Hybrid malicious attacks, including two typical attacks, i.e., denial-of-service (DoS) attacks and false data injection (FDI) attacks, are considered in the communication networks. Under DoS attacks, the control signals will be interfered, which cause the degradation of signal-to-interference-plus-noise ratio, then lead to packets loss. Under FDI attacks, the false signals are injected and output signals are modified so that the system performance is deteriorated. For the NCS subject to hybrid attacks, a secure observer that can resist FDI attacks is devised and a fuzzy MPC algorithm that can solve the controller gains is proposed. Besides, by updating the bound of augmented estimation error, the recursive feasibility can be guaranteed. Finally, illustrative examples are given to show the effectiveness of proposed scheme.

19.
Stem Cell Res Ther ; 14(1): 52, 2023 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-36959678

RESUMO

BACKGROUND: Endogenous neural stem cells (NSCs) are critical for the remyelination of axons following spinal cord injury (SCI). Cell-cell communication plays a key role in the regulation of the differentiation of NSCs. Astrocytes act as immune cells that encounter early inflammation, forming a glial barrier to prevent the spread of destructive inflammation following SCI. In addition, the cytokines released from astrocytes participate in the regulation of the differentiation of NSCs. The aim of this study was to investigate the effects of cytokines released from inflammation-stimulated astrocytes on the differentiation of NSCs following SCI and to explore the influence of these cytokines on NSC-NSC communication. RESULTS: Lipopolysaccharide stimulation of astrocytes increased bone morphogenetic protein 2 (BMP2) release, which not only promoted the differentiation of NSCs into astrocytes and inhibited axon remyelination in SCI lesions but also enriched miRNA-22-3p within extracellular vesicles derived from NSCs. These miRNA-22 molecules function as a feedback loop to promote NSC differentiation into oligodendrocytes and the remyelination of axons following SCI by targeting KDM3A. CONCLUSIONS: This study revealed that by releasing BMP2, astrocytes were able to regulate the differentiation of NSCs and NSC-NSC communication by enriching miRNA-22 within NSC-EVs, which in turn promoted the regeneration and remyelination of axons by targeting the KDM3A/TGF-beta axis and the recovery of neurological outcomes following SCI.


Assuntos
MicroRNAs , Células-Tronco Neurais , Remielinização , Traumatismos da Medula Espinal , Humanos , Astrócitos/metabolismo , Células-Tronco Neurais/metabolismo , Diferenciação Celular/fisiologia , Traumatismos da Medula Espinal/patologia , Inflamação/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Histona Desmetilases com o Domínio Jumonji/genética , Histona Desmetilases com o Domínio Jumonji/metabolismo
20.
World J Stem Cells ; 15(9): 947-959, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37900941

RESUMO

BACKGROUND: Rapid wound healing remains a pressing clinical challenge, necessitating studies to hasten this process. A promising approach involves the utilization of human umbilical cord mesenchymal stem cells (hUC-MSCs) derived exosomes. The hypothesis of this study was that these exosomes, when loaded onto a gelatin sponge, a common hemostatic material, would enhance hemostasis and accelerate wound healing. AIM: To investigate the hemostatic and wound healing efficacy of gelatin sponges loaded with hUC-MSCs-derived exosomes. METHODS: Ultracentrifugation was used to extract exosomes from hUC-MSCs. Nanoparticle tracking analysis (NTA), transmission electron microscopy (TEM), and western blot techniques were used to validate the exosomes. In vitro experiments were performed using L929 cells to evaluate the cytotoxicity of the exosomes and their impact on cell growth and survival. New Zealand rabbits were used for skin irritation experiments to assess whether they caused adverse skin reactions. Hemolysis test was conducted using a 2% rabbit red blood cell suspension to detect whether they caused hemolysis. Moreover, in vivo experiments were carried out by implanting a gelatin sponge loaded with exosomes subcutaneously in Sprague-Dawley (SD) rats to perform biocompatibility tests. In addition, coagulation index test was conducted to evaluate their impact on blood coagulation. Meanwhile, SD rat liver defect hemostasis model and full-thickness skin defect model were used to study whether the gelatin sponge loaded with exosomes effectively stopped bleeding and promoted wound healing. RESULTS: The NTA, TEM, and western blot experimental results confirmed that exosomes were successfully isolated from hUC-MSCs. The gelatin sponge loaded with exosomes did not exhibit significant cell toxicity, skin irritation, or hemolysis, and they demonstrated good compatibility in SD rats. Additionally, the effectiveness of the gelatin sponge loaded with exosomes in hemostasis and wound healing was validated. The results of the coagulation index experiment indicated that the gelatin sponge loaded with exosomes had significantly better coagulation effect compared to the regular gelatin sponge, and they showed excellent hemostatic performance in a liver defect hemostasis model. Finally, the full-thickness skin defect healing experiment results showed significant improvement in the healing process of wounds treated with the gelatin sponge loaded with exosomes compared to other groups. CONCLUSION: Collectively, the gelatin sponge loaded with hUC-MSCs-derived exosomes is safe and efficacious for promoting hemostasis and accelerating wound healing, warranting further clinical application.

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