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1.
Biomater Sci ; 12(2): 507-517, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38088652

RESUMO

"Closed-loop" insulin-loaded microneedle patche shows great promise for improving therapeutic outcomes and life quality for diabetes patients. However, it is typically hampered by limited insulin loading capacity, random degradation, and intricate preparation procedures for the independence of the "closed-loop" bulk microneedles. In this study, we combined the solubility of microneedles and "closed-loop" systems and designed poly(vinyl alcohol)-based bulk microneedles (MNs@GI) through in situ photopolymerization for multi-responsive and sustained hypoglycemic therapy, which significantly simplified the preparation process and improved insulin loading. GOx/insulin co-encapsulated MNs@GI with a phenylboronic ester structure improved glycemic responsiveness to control the insulin release under high glucose conditions and reduced inflammation risk in the normal skin. MNs@GI could further degrade to increase insulin release due to the crosslinked acetal-linkage hydrolysis in the presence of gluconic acid, which was caused by GOx-mediated glucose-oxidation in a hyperglycemic environment. The in vivo results showed that MNs@GI effectively regulated glycemic levels within the normal range for approximately 10 h compared to that of only insulin-loaded microneedles (MNs@INS). Consequently, the highly insulin-loaded, multi-responsive, and pH-triggered MN system has tremendous potential for diabetes treatment.


Assuntos
Diabetes Mellitus Experimental , Hipoglicemiantes , Animais , Humanos , Hipoglicemiantes/uso terapêutico , Sistemas de Liberação de Medicamentos/métodos , Insulina/química , Glucose/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Concentração de Íons de Hidrogênio
2.
Eur J Pharmacol ; 957: 175969, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37567457

RESUMO

Pathological myocardial hypertrophy initially develops as an adaptive response to cardiac stress, which can be induced by many diseases. It is accompanied by adverse cardiovascular events, including heart failure, arrhythmias, and death. The purpose of this research was to explore the molecular mechanism of a novel peptide Athycaltide-1 (ATH-1) in the treatment of Ang II-induced pathological myocardial hypertrophy. In this study, the mRNA of Control group, Ang II group, ATH-1 group and Losartan group mice were sequenced by high-throughput sequencing technology. The results showed that the differentially expressed genes (DEGs) were significantly enriched in cell response to oxidative stress, regulation of reactive oxygen species metabolism and calmodulin binding. Then, the oxidation level of mouse hearts and H9c2 cardiomyocytes in each group and the expression of key proteins of CaMKII/HDAC/MEF2C and ERK1/2 signaling pathways were detected to preliminarily verify the positive effect of ATH-1. At the same time, the effect of ATH-1 was further determined by adding reactive oxygen species (ROS) inhibitor N-acetylcysteine (NAC) and CaMKII inhibitor AIP in vitro. The results showed that ATH-1 could significantly reduce the level of oxidative stress in hypertrophic cardiomyocytes and inhibiting the activation of CaMKII and ERK1/2.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Sistema de Sinalização das MAP Quinases , Animais , Camundongos , Angiotensina II/efeitos adversos , Angiotensina II/metabolismo , Angiotensina II/toxicidade , Sinalização do Cálcio , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Cardiomegalia/induzido quimicamente , Cardiomegalia/tratamento farmacológico , Cardiomegalia/metabolismo , Células Cultivadas , Miócitos Cardíacos , Peptídeos/farmacologia , Espécies Reativas de Oxigênio/metabolismo
3.
ACS Appl Mater Interfaces ; 15(28): 33309-33321, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37408134

RESUMO

Chemotherapy predominates in clinical treatment of prostate cancer (PCa), while irreversible resistance to chemotherapeutics and severe side effects hinder the therapeutic efficacy, especially in castration-resistant PCa (CRPC). Herein, a bombesin (BBN)-decorated two-in-one prodrug (T-NO/E2-PMs) incorporating a polymeric nitric oxide (NO) donor and acetal-linked 17ß-estradiol (E2) in one backbone is developed, aiming to inhibit androgen receptor (AR) expression, reprogram the tumor microenvironment of CRPC, and enhance estradiol-mediated hypoxic CRPC therapy. Following efficient internalization mediated by BBN, T-NO/E2-PMs releases estradiol and NO in response to the unique intracellular environments. Both in vitro and in vivo studies demonstrate that the T-NO/E2-PMs nano-prodrug along with NO release potently downregulates AR levels to reverse CRPC and further enhances the chemo-sensitization of estradiol to PCa PC-3 cell apoptosis and the inhibition of metastasis. Collectively, this two-in-one nano-prodrug strategy offers a promising platform for construction of advanced nanomedicine to boost the therapeutic efficacy.


Assuntos
Pró-Fármacos , Neoplasias de Próstata Resistentes à Castração , Masculino , Humanos , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/metabolismo , Neoplasias de Próstata Resistentes à Castração/patologia , Pró-Fármacos/farmacologia , Pró-Fármacos/uso terapêutico , Doadores de Óxido Nítrico/farmacologia , Doadores de Óxido Nítrico/uso terapêutico , Próstata/patologia , Estradiol , Óxido Nítrico/uso terapêutico , Linhagem Celular Tumoral , Microambiente Tumoral
4.
J Phys Chem Lett ; 14(31): 6948-6955, 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37498356

RESUMO

A fundamental understanding of the reactivity evolution of nanosized clusters at an atomically precise level is pivotal to assemble desired materials with promising candidates. Benefiting from the tandem mass spectrometer coupled with a high-temperature ion-trap reactor, the reactions of mass-selected Con- (n = 5-25) clusters with CO2 were investigated and the increased reactivity of Co20-25- was newly discovered herein. This finding marks an important step to understand property evolution of subnanometer metal clusters (Co25-, ∼0.8 nm) atom-by-atom. The reasons behind the increased reactivity of Co20-25- were proposed by analyzing the reactions of smaller Co6-8- clusters that exhibit significantly different reactivity toward CO2, in which a lower electron affinity of Con contributes to the capture of CO2 while the flexibility of Con- could play vital roles to stabilize reaction intermediates and suppress the barriers of O-CO rupture and CO desorption.

5.
Dalton Trans ; 52(20): 6668-6676, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37114992

RESUMO

The key to optimizing energy-consuming catalytic conversions lies in acquiring a fundamental understanding of the nature of the active sites and the mechanisms of elementary steps at an atomically precise level, while it is challenging to capture the crucial step that determines the overall temperature of a real-life catalytic reaction. Herein, benefiting from a newly-developed high-temperature ion trap reactor, the reverse water-gas shift (CO2 + H2 → CO + H2O) reaction catalyzed by the Rhn- (n = 3-11) clusters was investigated under variable temperatures (298-783 K) and the critical temperature that each elementary step (Rhn- + CO2 and RhnO- + H2) requires to take place was identified. The Rh4- cluster strikingly surpasses other Rhn- clusters to drive the catalysis at a mild starting temperature (∼440 K). This finding represents the first example that a specifically sized cluster catalyst that works under an optimum condition can be accurately filtered by using state-of-the-art mass spectrometric experiments and rationalized by quantum-chemical calculations.

6.
Toxicology ; 492: 153530, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37121536

RESUMO

Endemic fluorosis is a global public health problem. Cardiovascular diseases caused by fluoride are closely related to endothelial cell injury. Metabolism disorder of endothelial cells (ECs) are recognized as the key factor of endothelial dysfunction which has been a hot topic in recent years. However, the toxic effect of fluoride on vascular endothelium has not been elucidated. The aim of this study was to explore the alteration of endothelial cell metabolites in Human Umbilical Vein Endothelial Cells (HUVECs) exposed to NaF using LC-MS/MS technique. The screening conditions were Variable Importance for the Projection (VIP) > 1 and P < 0.05. It was found that the expression of the metabolites Lumichrome and S-Methyl-5'-thioadenosine was upregulated and of the other metabolites, such as Creatine, L-Glutamate, Stearic acid was downregulated. Differential metabolites were found to be primarily related to FoxO、PI3K/Akt and apoptosis signaling pathways by Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. From the perspective of metabolism, this study explored the possible mechanism of fluoride induced endothelial cell injury which providing theories and clues for subsequent studies.


Assuntos
Fluoretos , Fosfatidilinositol 3-Quinases , Humanos , Cromatografia Líquida , Fosfatidilinositol 3-Quinases/metabolismo , Espectrometria de Massas em Tandem , Células Endoteliais da Veia Umbilical Humana
7.
Front Neurosci ; 16: 1026127, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36466171

RESUMO

The purpose of this study was to assess the efficacy and safety of the combination of tirofiban with intravenous thrombolysis (IVT) in treating patients with capsular warning syndrome (CWS) who failed to respond to the treatment of intravenous thrombolysis alone. Tirofiban was approved for the treatment of CWS patients with fluctuating symptoms or no substantial improvement after intravenous thrombolysis within 24 h in our hospital from October 2019 to June 2021. Patients were evaluated with the National Institutes of Health Stroke Scale (NIHSS) at admission, at 72 h post-thrombolysis, at 1-week, and at 3-months with the modified Rankin Scales (MRS) score. A total of 12 patients received tirofiban and eight patients received control treatment with a history of CWS in our cohort. Among the patients, 13 patients smoked more than one pack of cigarettes a day, 17 had hypertension, 17 had hypercholesterolemia, 7 had diabetes, 1 had the history of cerebral infarction, 2 had atrial fibrillation, 7 had mild big vascular stenosis, 13 had lesions of the perforating branch by imaging, and 19 had acute capsular infarction. In both the tirofiban and control groups, NIHSS scores were significantly reduced after intravenous thrombolysis or 1-week after onset compared with before intravenous thrombolysis (P < 0.001). Before and after intravenous thrombolysis, there were no differences between the tirofiban group and control group (P = 0.970, P = 0.384, respectively). The tirofiban group, however, showed remarkably lower scores in both 1-week NIHSS and 3-month MRS than the control (P = 0.012, P = 0.003, respectively). Our study revealed that tirofiban did not increase the risk of hemorrhage and had favorable clinical efficacy as a remedial treatment for CWS patients with poor prognosis for intravenous thrombolysis, therefore indicating great potential for broader use.

8.
Phys Chem Chem Phys ; 24(48): 29765-29771, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36458914

RESUMO

Identifying the structural configurations of precursors for CO dissociation is fundamentally interesting and industrially important in the fields of, e.g., Fischer-Tropsch synthesis. Herein, we demonstrated that CO could be dissociated on polynuclear vanadium nitride V4N5- clusters at room temperature, and a key intermediate, with CO in a N-assisted tilted bridge coordination where the C-O bond ruptures easily, was discovered. The reaction was characterized by mass spectrometry, photoelectron spectroscopy, and quantum-chemistry calculations, and the nature of the adsorbed CO on product V4N5CO- was further characterized by a collision-induced dissociation experiment. Theoretical analysis evidences that CO dissociation is predominantly governed by the low-coordinated V and N atoms on the (V3N4)VN- cluster and the V3N4 moiety resembles a support. This finding strongly suggests that a novel mode for facile CO dissociation was identified in a gas-phase cluster study.

9.
Int J Gen Med ; 15: 8191-8200, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36411815

RESUMO

Introduction: There is no effective treatment plan for coronavirus disease 2019 (COVID-19). We employed a combination of Chinese and Western medicine treatment for some COVID-19 inpatients. Methods: This study was a prospective cohort study that observed non-critical COVID-19 inpatients. The differences will be observed in the time from admission to two consecutive 2019-nCoV nucleic acid test negatives and the Visual Analog Scale (VAS) score between the two groups. Results: A total of 254 confirmed COVID-19 patients were included in this study. The median time from the admission to two consecutive negative nucleic acid tests was 14 days for the integrated Chinese and Western Medicine (ICWM) group, while the Western Medicine (WM) group was 16 days. Besides, the median VAS score of the ICWM group was 0, which was an average decrease of 2 points compared to the time of admission. Conclusion: For non-critical COVID-19 patients, it was safe and have more benefits to add traditional Chinese medicine decoction based on WM treatment.

10.
J Phys Chem A ; 126(32): 5294-5301, 2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-35943908

RESUMO

The discovery of compounds containing transition metals with an unusual and well-established oxidation state is vital to enrich our horizon on formal oxidation state. Herein, benefiting from the study of the water-gas shift reaction (CO + H2O → CO2 + H2) mediated with the iridium-vanadium oxide cluster IrVO2-, the missing -II oxidation state of iridium was identified. The reactions were performed by using our newly developed double ion trap reactors that can spatially separate the addition of reactants and are characterized by mass spectrometry and quantum-chemical calculations. This finding makes an important step that all the proposed 13 oxidation states of iridium (+IX to -III) have been known. The iridium atom in the IrVO2- cluster features the Ir═V double bond and resembles chemically the coordinated oxygen atom. A reactivity study demonstrated that the flexible role switch of iridium between an oxygen-atom like (Ir-IIVO2-) and a transition-metal-atom like behavior (Ir+IIVO3-) in different species can drive the water-gas shift reaction in the gas phase under ambient conditions. This result parallels and well rationalizes the extraordinary reactivity of oxide-supported iridium single-atom catalysts in related condensed-phase reactions.

11.
Dalton Trans ; 51(30): 11491-11498, 2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35833563

RESUMO

Noble metals dispersed on transition-metal carbides exhibit extraordinary activity in CO2 catalytic conversion and bimetallic carbides generated at the interface were proposed to contribute to the observed activity. Heteronuclear metal carbide clusters (HMCCs) that compositionally resemble the bimetallic carbides are suitable models to get a fundamental understanding of the reactivity of the related condensed-phase catalysts, while the reaction of HMCCs with CO2 has not been touched in the gas phase. Herein, benefiting from the newly designed double ion trap reactors, the reaction of laser-ablation generated and mass-selected RhTaC2- clusters with CO2 was studied. The experimental results identified that RhTaC2- can reduce four CO2 molecules consecutively and generate the product RhTaC2O4-. The pivotal roles of Rh-Ta synergy and the C2 ligand in driving CO2 reduction were rationalized by theoretical calculations. The presence of an attached CO unit on the product RhTaC2O4- was evidenced by the collision-induced dissociation experiment, providing a fundamental strategy to alleviate carbon deposition under a CO2 atmosphere at elevated temperatures.

12.
Phys Chem Chem Phys ; 24(23): 14616-14622, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35670100

RESUMO

The reverse water-gas shift (RWGS, CO2 + H2 → CO + H2O, ΔH298 = +0.44 eV) reaction mediated by the diatomic anion Rh2- was successfully constructed. The generation of a gas-phase H2O molecule and ion product [Rh2(CO)ads]- was identified unambiguously at room temperature and the only elementary step that requires extra energy to complete the catalysis is the desorption of CO from [Rh2(CO)ads]-. This experimentally identified Rh2- anion represents the first gas-phase species that can drive the RWGS reaction because it is challenging to design effective routes to yield H2O from CO2 and H2. The reactions were performed by using our newly developed double ion trap reactors and characterized by mass spectrometry, photoelectron spectroscopy, and high-level quantum-chemical calculations. We found that the order that the reactants (CO2 or D2) were fed into the reactor did not have a pronounced impact on the reactivity and the final product distribution (D2O and Rh2CO-). The atomically precise insights into the key steps to guide the reaction toward the RWGS direction were provided.

13.
J Phys Chem Lett ; 12(28): 6519-6525, 2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34240876

RESUMO

The generation and characterization of multiple metal-metal (M-M) bonds between early and late transition metals is vital to correlate the nature of multiple M-M bonds with the related reactivity in catalysis, while the examples with multiple M-M bonds have been rarely reported. Herein, we identified that the quadruple bonding interactions were formed in a gas-phase ion IrV+ with a dramatically short Ir-V bond. Oxidation of four CO molecules by IrVO4+ is a highly exothermic process driven by the generation of stable products IrV+ and CO2, and then IrV+ can be oxidized by N2O to regenerate IrVO4+. This finding overturns the general impression that vanadium oxide clusters are unwilling to oxidize multiple CO molecules because of the strong V-O bond and that at most two oxygen atoms can be supplied from a single V-containing cluster in CO oxidation. This study emphasizes the potential importance of heterobimetallic multiple M-M bonds in related heterogeneous catalysis.

14.
J Phys Chem A ; 125(17): 3710-3717, 2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-33899469

RESUMO

Laser ablation generated CoCDn- (n = 0-4) anions were mass selected and then reacted with CO2 in an ion trap reactor. The reactions were characterized by mass spectrometry and quantum chemical calculations. The experimental results demonstrated that the CoC- anion can convert CO2 into CO. In contrast, the bare Co- anion is inert toward CO2. Coordinated D ligands can modify the reactivity of CoCD1-4- in which CoCD1-3- can reduce CO2 into CO selectively and CoCD4- can only adsorb CO2. The crucial roles of the coordinated C and D ligands to tune the reactivity of CoCDn- (n = 0-4) toward CO2 were rationalized by theoretical calculations. Note that the hydrogenation process that is usually observed in the reactions of gas-phase metal hydrides with CO2 is completely suppressed for the reactions CoCDn- + CO2. This study provides insights into the molecular-level origin for the observations that CO can be selectively generated from CO2 catalyzed by cobalt-containing carbides in heterogeneous catalysis.

15.
J Phys Chem A ; 124(41): 8414-8420, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32936643

RESUMO

The hydrogenation of CO2 into value-added complexes is of great importance for both environmental and economic issues. Metal hydrides are good models for the active sites to explore the nature of CO2 hydrogenation; however, the fundamental insights into C-H bond formation are still far from clear because of the complexity of real-life catalysts. Herein, gas-phase reactions of the Fe2Hn- (n = 0-3) anions with CO2 were investigated using mass spectrometry and quantum chemical calculations. The experimental results showed that the reduction of CO2 into CO dominates all of these reactions, whereas Fe2H- and Fe2H2- can induce the hydrogenation of CO2 effectively to give rise to products Fe(HCO2)- and HFe(HCO2)-, respectively. The mechanistic aspects and the reactivity of Fe2Hn- with an increased number of H atoms in CO2 hydrogenation were rationalized by theoretical calculations.

16.
Zhongguo Zhen Jiu ; 36(4): 443-7, 2016 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-27352515

RESUMO

With the key words such as acupuncture and moxibustion, coronary heart disease, etc., CNKI, WANFANG and VIP databases were retrieved to get Chinese literature of coronary heart disease treated with acupuncture and moxibustion in recent 10 years. Related 76 articles were collected and 72 acupoints were applied. The potential relation among acupoints of the top 20 was analyzed by hierarchical cluster analysis. It was discovered that the main acupoints were Neiguan (PC 6), Xinshu (BL 15), Danzhong (CV 17), Geshu (BL 17) and Zusanli (ST 36), etc., especially the specific acupoints. The back-shu points and five-shu points were emphasized. Pericardium meridian of hand-jueyin was the high frequency meridian. The four extremities were the main position.


Assuntos
Pontos de Acupuntura , Terapia por Acupuntura , Doença da Artéria Coronariana/terapia , Moxibustão , Bases de Dados Bibliográficas , Humanos , Meridianos
17.
Zhongguo Zhen Jiu ; 35(1): 50-2, 2015 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-25906569

RESUMO

In order to have a better basic research of needle sticking, reports regarding basic research of needle sticking in recent years are arranged and summarized, including the concepts of needle sticking, the history origin, manipulation methods, precautions and selection requirements of needles. In the meanwhile, the reinforcing and reducing manipulation in sticking of the needle is preliminarily analyzed, and based on analysis of ancient records, three hypotheses are proposed: (1) needle sticking partly belongs to reinforcing method; (2) needle sticking partly belongs to reducing method; (3) needle sticking can perform reinforcing and reducing effects according to different manipulations. It is also believed that the needle sticking in modern clinical research is mostly used for reducing effects. However reinforcing and reducing manipulation in sticking of the needle still lacks of the support from ancient literature theory and modern clinical application, which needs to be improved.


Assuntos
Terapia por Acupuntura/métodos , Terapia por Acupuntura/instrumentação , Humanos , Medicina na Literatura , Agulhas
18.
J Agric Food Chem ; 58(8): 4894-900, 2010 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-20230001

RESUMO

Effects of enzymatic hydrolysates of whey protein concentrates (WPC) on iron absorption were studied using in vitro digestion combined with Caco-2 cell models for improved iron absorption. Neutrase- and papain-treated WPC could improve iron absorption; especially hydrolysates by Neutrase could significantly increase iron absorption to 12.8% compared to 3.8% in the control. Hydrolysates by alcalase had negative effects to the lowest at 0.57%. Two new bands at molecular weights (MW) around and below 10 kDa occurred at tricine-SDS-PAGE of hydrolysates by Neutrase, and one new band at MW below 10 kDa occurred in hydrolysates by papain. No new band was observed in hydrolysates by alcalase. Concentration of free amino acids indicated that, except for tyrosine and phenylalanine, amino acids in papain-treated hydrolysates were higher than that of alcalase, and no cysteine and proline were found in hydrolysates by alcalase. The results suggested that hydrolysate by Neutrase-treated WPC is a promising facilitator for iron absorption. Peptides of MW around and lower than 10 kDa and aspartic acid, serine, glutamic acid, glycin, cysteine, histidine, and proline may be contributors to enhancement.


Assuntos
Ferro/metabolismo , Metaloendopeptidases/metabolismo , Papaína/metabolismo , Subtilisinas/metabolismo , Células CACO-2 , Eletroforese em Gel de Poliacrilamida , Humanos , Hidrólise
19.
Zhongguo Zhen Jiu ; 25(2): 79-81, 2005 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-16312883

RESUMO

OBJECTIVE: To study the optimum acupuncture treatment program and the mechanism for treatment of cerebral infarction. METHODS: Sixty-three cases were randomly divided into 9 groups. The four factors, times of manipulation, the retaining time of the needle, acupuncture instrument and acupoints,and their corresponding three levels were adopted respectively in treatment of each group. Then nerve function defect score and insulin resistance were observed before and after treatment. RESULTS: The acupoints, the times of manipulation and the retaining time of the needle have significant effects on nerve function defect and insulin resistance (P < 0.01 or P < 0.05), and the acupuncture instrument has a significant effect on insulin resistance (P < 0.01). The choice of acupoints was the most important factor for acupuncture treatment of cerebral infarction. CONCLUSION: Acupuncture for regulating The Governor Vessel with twice manipulations and retaining the needle for 60 min is optimum treatment program for cerebral infarction. The good regulating effect of acupuncture on insulin resistance is one of the mechanisms of achieving the therapeutic results.


Assuntos
Terapia por Acupuntura , Resistência à Insulina , Pontos de Acupuntura , Infarto Cerebral , Humanos , Agulhas
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