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1.
Environ Sci Technol ; 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39250812

RESUMO

Water is ubiquitous in various heterogeneous catalytic reactions, where it can be easily adsorbed, chemically dissociated, and diffused on catalyst surfaces, inevitably influencing the catalytic process. However, the specific role of water in these reactions remains unclear. In this study, we innovatively propose that H2O-driven surface lattice oxygen activation in γ-MnO2 significantly enhances low-temperature NH3-SCR. The proton from water dissociation activates the surface lattice oxygen in γ-MnO2, giving rise to a doubling of catalytic activity (achieving 90% NO conversion at 100 °C) and remarkable stability. Comprehensive in situ characterizations and calculations reveal that spontaneous proton diffusion to the surface lattice oxygen reduces the orbital overlap between the protonated oxygen atom and its neighboring Mn atom. Consequently, the Mn-O bond is weakened and the surface lattice oxygen is effectively activated to provide excess oxygen vacancies available for converting O2 into O2-. Therefore, the redox property of Mn-H is improved, leading to enhanced NH3 oxidation-dehydrogenation and NO oxidation processes, which are crucial for low-temperature NH3-SCR. This work provides a deeper understanding and fresh perspectives on the water promotion mechanism in low-temperature NOx elimination.

2.
Diabetes Obes Metab ; 25(5): 1229-1240, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36594724

RESUMO

AIMS: To evaluate the efficacy and safety of janagliflozin, a selective renal sodium-glucose cotransporter-2 inhibitor, as monotherapy in drug-naive Chinese patients with type 2 diabetes mellitus (T2DM). MATERIALS AND METHODS: This Phase 3 trial included a 24-week, multicentre, randomized, double-blind, placebo-controlled period, followed by a 28-week extension period. A total of 432 patients with glycated haemoglobin (HbA1c) levels ≥7.0% (53 mmol/mol) and ≤10.5% (91 mmol/mol) were randomized (1:1:1) to receive once-daily placebo, 25 mg or 50 mg janagliflozin. After 24 weeks, patients on placebo were switched and re-randomized (1:1) to 25 mg or 50 mg janagliflozin, whereas patients on janagliflozin maintained the initial therapy. The primary endpoint was change from baseline in HbA1c after 24 weeks. RESULTS: At Week 24, the placebo-adjusted least squares mean changes in HbA1c were -0.80% (95% confidence interval [CI] -0.98% to -0.62%)/-8.7 mmol/mol (95% CI -10.7 mmol/mol to -6.8 mmol/mol) and -0.88% (95% CI -1.06% to -0.70%)/-9.6 mmol/mol (95% CI -11.6 mmol/mol to -7.7 mmol/mol), respectively (P < 0.001 for both). A higher proportion of patients achieved HbA1c <7.0% (53 mmol/mol) with janagliflozin 25 mg and janagliflozin 50 mg compared with placebo (47.2%, 49.3%, and 23.5%, respectively). Both janagliflozin doses significantly decreased fasting plasma glucose, 2-hour postprandial glucose, body weight and systolic blood pressure, as well as increased high-density lipoprotein (HDL) cholesterol and insulin sensitivity compared with placebo (P < 0.05 for all). The trends in improvement of these variables were sustained during the 28-week extension period. Overall incidences of adverse events were 67.8%, 71.5% and 60.7% with janagliflozin 25 mg, janagliflozin 50 mg and placebo, respectively. The incidence of urinary tract infections and genital fungal infections was low. No severe hypoglycaemia or ketoacidosis occurred. CONCLUSIONS: Janagliflozin 25 mg and 50 mg monotherapy once-daily effectively improved glycaemic control, reduced body weight and blood pressure, improved HDL cholesterol and insulin sensitivity, and was generally well tolerated.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Hipoglicemiantes/uso terapêutico , Hemoglobinas Glicadas , População do Leste Asiático , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos , Resultado do Tratamento , Dieta , Peso Corporal , Quimioterapia Combinada , Glucose/uso terapêutico , Método Duplo-Cego , Glicemia
3.
Diabetes Obes Metab ; 25(3): 785-795, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36433709

RESUMO

AIM: To evaluate the efficacy and safety of janagliflozin in Chinese patients with type 2 diabetes (T2D) inadequately controlled with metformin monotherapy. MATERIALS AND METHODS: This multicentre phase 3 trial included a 24-week, randomized, double-blind, placebo-controlled period, followed by a 28-week extension period. Patients (N = 421) with HbA1c of 7.0% or higher and 10.5% or less were randomized (1:1:1) to receive once-daily placebo, janagliflozin 25 or 50 mg. After the 24-week treatment period, patients on placebo were re-randomized (1:1) to janagliflozin 25 or 50 mg for the additional 28-week treatment, whereas patients on janagliflozin maintained the same therapy. The primary endpoint was the change from baseline in HbA1c to week 24. RESULTS: At week 24, the placebo-adjusted least squares mean changes of HbA1c were -0.58% and -0.58% with janagliflozin 25 and 50 mg, respectively (P < .0001 for both). The proportion of patients achieving HbA1c less than 7.0% was higher with janagliflozin 25 and 50 mg compared with placebo (41.8%, 41.7% and 28.0%, respectively). Both janagliflozin doses provided significant reductions in fasting plasma glucose, 2-hour postprandial glucose, body weight and systolic blood pressure, and improvements in high-density lipoprotein cholesterol and insulin sensitivity compared with placebo (P < .05 for all). The trends in improvement of these variables were retained during the 28-week extension period. No severe hypoglycaemia occurred throughout the whole 52-week treatment. CONCLUSIONS: Janagliflozin 25 or 50 mg once-daily added to metformin therapy significantly improved glycaemic control, reduced body weight and systolic blood pressure, improved high-density lipoprotein cholesterol and insulin sensitivity, and was generally well-tolerated by Chinese T2D patients who had poor glycaemic control with metformin monotherapy.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Metformina , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Glicemia , Peso Corporal , Colesterol , Método Duplo-Cego , Quimioterapia Combinada , População do Leste Asiático , Hemoglobinas Glicadas , Hipoglicemiantes/uso terapêutico , Lipoproteínas HDL , Metformina/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Resultado do Tratamento
4.
Environ Sci Technol ; 57(39): 14737-14746, 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37738479

RESUMO

Mn-based catalysts preferred in low-temperature selective catalytic reduction (SCR) are susceptible to SO2 poisoning. The stubborn sulfates make insufficient O2 activation and result in deficient reactive oxygen species (ROS) for activating reaction molecules. H2O has long been regarded as an accomplice to SO2, hastening catalyst deactivation. However, such a negative impression of the SCR reaction was reversed by our recent research. Here, we reported a H2O contribution over Mn-based SCR catalysts to counteract SO2 poisoning through accessible O2 activation, in which O2 was synergistically activated with H2O to generate ROS for less deactivation and more expected regeneration. The resulting ROS benefited from the energetically favorable route supported by water-induced Ea reduction and was actively involved in the NH3 activation and NO oxidation process. Besides, ROS maintained high stability over the SO2 + H2O-deactivated γ-MnO2 catalyst throughout the mild thermal treatment, achieving complete regeneration of its own NO disposal ability. This strategy was proven to be universally applicable to other Mn-based catalysts.

5.
Environ Sci Technol ; 56(14): 10442-10453, 2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35749227

RESUMO

A single-atom Ce-modified α-Fe2O3 catalyst (Fe0.93Ce0.07Ox catalyst with 7% atomic percentage of Ce) was synthesized by a citric acid-assisted sol-gel method, which exhibited excellent performance for selective catalytic reduction of NOx with NH3 (NH3-SCR) over a wide operating temperature window. Remarkably, it maintained ∼93% NO conversion efficiency for 168 h in the presence of 200 ppm SO2 and 5 vol % H2O at 250 °C. The structural characterizations suggested that the introduction of Ce leads to the generation of local Fe-O-Ce sites in the FeOx matrix. Furthermore, it is critical to maintain the atomic dispersion of the Ce species to maximize the amounts of Fe-O-Ce sites in the Ce-doped FeOx catalyst. The formation of CeO2 nanoparticles due to a high doping amount of Ce species leads to a decline in catalytic performance, indicating a size-dependent catalytic behavior. Density functional theory (DFT) calculation results indicate that the formation of oxygen vacancies in the Fe-O-Ce sites is more favorable than that in the Fe-O-Fe sites in the Ce-free α-Fe2O3 catalyst. The Fe-O-Ce sites can promote the oxidation of NO to NO2 on the Fe0.93Ce0.07Ox catalyst and further facilitate the reduction of NOx by NH3. In addition, the decomposition of NH4HSO4 can occur at lower temperatures on the Fe0.93Ce0.07Ox catalyst containing atomically dispersed Ce species than on the α-Fe2O3 reference catalyst, resulting in the good SO2/H2O resistance ability in the NH3-SCR reaction.

6.
Inorg Chem ; 60(16): 12506-12516, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34310118

RESUMO

Transition-metal phosphides and sulfides are considered as promising cocatalysts for the photocatalytic hydrogen evolution reaction (HER), and the cocatalytic effect can be improved by directed heterostructure engineering. In this study, a novel lattice-matched CoP/CoS2 heterostructure having a nanosheet morphology was developed as an HER cocatalyst and integrated in situ onto graphitic carbon nitride (g-C3N4) nanosheets via a successive phosphorization and vulcanization route. First-principles density functional theory calculations evidenced that the construction of the lattice-matched CoP/CoS2 heterostructure resulted in the redistribution of interface electrons, enhanced metallic characteristics, and improved H* adsorption. As a result of these effects, the CoP/CoS2 heterostructure cocatalyst formed a 2D/2D Schottky junction with the g-C3N4 nanosheets, thus promoting photoelectron transfer to CoP/CoS2 and realizing fast charge-carrier separation and good HER activity. As expected, the CoP/CoS2 heterostructure exhibited excellent cocatalytic activity, and the optimal loading of the cocatalyst on g-C3N4 enhanced its HER activity to 3.78 mmol g-1 h-1. This work furnishes a new perspective for the development of highly active noble-metal-free cocatalysts via heterostructure engineering for water splitting applications.

7.
Clin Chem Lab Med ; 59(11): 1784-1789, 2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-34225395

RESUMO

OBJECTIVES: This study aimed to evaluate the effectiveness and efficiency of competency-oriented clinical laboratory teaching combined with case-based learning (CBL) and improve the examination of students' competence of laboratory medicine. METHODS: A total of 107 medical laboratory medicine interns at the Affiliated Hospital of Xuzhou Medical University from June 2017 to July 2019 volunteered to participate in the study and were randomly assigned into a control group with training of the traditional teacher-centered method, and an experimental group under a CBL teaching program. Student basic theory tests and skill assessment were designed to evaluate what the students gained from their internship when they completed their studies at the Affiliated Hospital of Xuzhou Medical University. RESULTS: Compared to students in the control group taught with the teacher-centered method, those in the CBL teaching program had significantly higher theory test scores and skill assessment scores on average. Competencies with particularly significant improvement included identification and processing of instrument alarm information, analysis of test results, identification and solution of the problem, as well as identification and reporting of the critical value and clinical communication. CONCLUSIONS: The competency-oriented teaching method combined with CBL is an effective method for improving students' professional knowledge, increasing language expression, and enhancing interpersonal relationship and teamwork, which is worthy of being promoted in laboratory medicine teaching.


Assuntos
Capacitação em Serviço , Laboratórios Clínicos , Humanos
8.
Toxicol Appl Pharmacol ; 380: 114696, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31381904

RESUMO

TGFß signaling plays an important role in orchestrating a favorable microenvironment for tumor cell growth and promoting epithelial-mesenchymal transition. As a conventional nonsteroidal anti-inflammation drugs, tolfenamic acid (TA) has been previously reported to exhibit anti-cancer activity. Herein, we investigated the effect of TA on TGFß-mediated pro-metastatic activity and the underlying mechanisms in hepatocellular carcinoma (HCC). As a result, TA suppresses TGFß-induced migration and glycolysis in HCC cells, which is accompanied with reduced Smad phosphorylation and subsequent nuclear transcription activity. Mechanistically, TA promotes lipid raft-caveolar internalization pathway of TGFß receptor, therefore leading to its rapid turnover. Consistently, TA inhibits constitutively active TGFß type I receptor induced Smad phosphorylation and EMT markers, whereas ectopic expression of TGFß type II receptor could partially rescue TGFß-mediated Smad2 phosphorylation and downstream genes expression in the presence of TA. Furthermore, TA inhibited HCC cells invasion in nude mice, associated with the alteration of characteristics related with EMT and glycolysis of cancer cells. Our study suggests TA could activate lipid raft pathway and modulate TGFß mediated metastasis, implicating the potential application of TA as a modulator of tumor microenvironment in HCC.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Antineoplásicos/farmacologia , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Microdomínios da Membrana/efeitos dos fármacos , Fator de Crescimento Transformador beta/metabolismo , ortoaminobenzoatos/farmacologia , Animais , Anti-Inflamatórios não Esteroides/uso terapêutico , Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal , Feminino , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Camundongos Endogâmicos BALB C , Camundongos Nus , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Transdução de Sinais/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos , ortoaminobenzoatos/uso terapêutico
9.
Phys Chem Chem Phys ; 17(24): 15996-6006, 2015 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-26027847

RESUMO

Two different precursors, manganese nitrate (MN) and manganese acetate (MA), were employed to prepare two series of catalysts, i.e., xCuyMn(N)/TiO2 and xCuyMn(A)/TiO2, by a co-impregnation method. The catalysts were characterized by XRD, LRS, CO-TPR, XPS and EPR spectroscopy. The results suggest that: (1) both xCuyMn(N)/TiO2 and xCuyMn(A)/TiO2 catalysts exhibit much higher catalytic activities than an unmodified Cu/TiO2 catalyst in the NO + CO reaction. Furthermore, the activities of catalysts modified with the same amount of manganese are closely dependent on manganese precursors. (2) The enhancement of activities for Mn-modified catalysts should be attributed to the formation of the surface synergetic oxygen vacancy (SSOV) Cu(+)-□-Mn(y+) in the reaction process. Moreover, since the formation of the SSOV (Cu(+)-□-Mn(3+)) in the xCuyMn(N)/TiO2 catalyst is easier than that (Cu(+)-□-Mn(2+)) in the xCuyMn(A)/TiO2 catalyst, the activity of the xCuyMn(N)/TiO2 catalyst is higher than that of the xCuyMn(A)/TiO2 catalyst. This conclusion is well supported by the XPS and EPR results.

10.
Cancer Cell ; 10(2): 159-70, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16904613

RESUMO

Endothelial cells in growing tumors express activated Akt, which when modeled by transgenic endothelial expression of myrAkt1 was sufficient to recapitulate the abnormal structural and functional features of tumor blood vessels in nontumor tissues. Sustained endothelial Akt activation caused increased blood vessel size and generalized edema from chronic vascular permeability, while acute permeability in response to VEGF-A was unaffected. These changes were reversible, demonstrating an ongoing requirement for Akt signaling for the maintenance of these phenotypes. Furthermore, rapamycin inhibited endothelial Akt signaling, vascular changes from myrAkt1, tumor growth, and tumor vascular permeability. Akt signaling in the tumor vascular stroma was sensitive to rapamycin, suggesting that rapamycin may affect tumor growth in part by acting as a vascular Akt inhibitor.


Assuntos
Células Endoteliais/patologia , Endotélio Vascular/patologia , Neoplasias/irrigação sanguínea , Neovascularização Patológica/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Sirolimo/farmacologia , Animais , Permeabilidade Capilar , Células Cultivadas , Edema/metabolismo , Células Endoteliais/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Humanos , Camundongos , Camundongos Transgênicos , Proteínas Proto-Oncogênicas c-akt/genética , Ratos , Transdução de Sinais , Fator A de Crescimento do Endotélio Vascular/fisiologia
11.
Spectrochim Acta A Mol Biomol Spectrosc ; 323: 124920, 2024 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-39111030

RESUMO

In this work, up- and down-conversion dual-emission CDs without rare-earth (UD D-CDs) were synthesized using RhB and 1,4-Diaminoanthraquinone as precursors. The synthesized UD D-CDs exhibited dual emissions at 496 and 580 nm under 260 and 865 nm excitation, respectively. The fluorescence emission mechanism, including contributions from carbon nuclei, surface states, molecular states, and internal defect states, was discussed through the separation and purification of UD D-CDs. Based on the interaction between UD D-CDs and copper ions (Cu2+), a dual-mode ratio fluorescence probe was developed to detect and quantify Cu2+. The up-conversion ratio fluorescent probe shows a linear range of 0.0500-15.0 µM, with a detection limit as low as 2.76 nM. This method has been successfully applied to detecting Cu2+ in human serum and has potential applications in biochemical analysis and biological imaging. The successful preparation of up-conversion fluorescent carbon dots without rare earth elements and the ability to perform low-damage detection in high-background biological samples provide a new approach to constructing non-rare earth up-conversion probes.

12.
Front Microbiol ; 15: 1428304, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39077742

RESUMO

Bloodstream infections (BSIs) are a critical medical concern, characterized by elevated morbidity, mortality, extended hospital stays, substantial healthcare costs, and diagnostic challenges. The clinical outcomes for patients with BSI can be markedly improved through the prompt identification of the causative pathogens and their susceptibility to antibiotics and antimicrobial agents. Traditional BSI diagnosis via blood culture is often hindered by its lengthy incubation period and its limitations in detecting pathogenic bacteria and their resistance profiles. Surface-enhanced Raman scattering (SERS) has recently gained prominence as a rapid and effective technique for identifying pathogenic bacteria and assessing drug resistance. This method offers molecular fingerprinting with benefits such as rapidity, sensitivity, and non-destructiveness. The objective of this study was to integrate deep learning (DL) with SERS for the rapid identification of common pathogens and their resistance to drugs in BSIs. To assess the feasibility of combining DL with SERS for direct detection, erythrocyte lysis and differential centrifugation were employed to isolate bacteria from blood samples with positive blood cultures. A total of 12,046 and 11,968 SERS spectra were collected from the two methods using Raman spectroscopy and subsequently analyzed using DL algorithms. The findings reveal that convolutional neural networks (CNNs) exhibit considerable potential in identifying prevalent pathogens and their drug-resistant strains. The differential centrifugation technique outperformed erythrocyte lysis in bacterial isolation from blood, achieving a detection accuracy of 98.68% for pathogenic bacteria and an impressive 99.85% accuracy in identifying carbapenem-resistant Klebsiella pneumoniae. In summary, this research successfully developed an innovative approach by combining DL with SERS for the swift identification of pathogenic bacteria and their drug resistance in BSIs. This novel method holds the promise of significantly improving patient prognoses and optimizing healthcare efficiency. Its potential impact could be profound, potentially transforming the diagnostic and therapeutic landscape of BSIs.

13.
Curr Med Res Opin ; 40(10): 1697-1703, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39235266

RESUMO

OBJECTIVE: To compare the efficacy and safety of insulin degludec biosimilar B01411 (HS-IDeg) with originator insulin degludec-Tresiba (NN-IDeg) in Chinese patients with type 2 diabetes mellitus (T2DM) who were inadequately controlled on oral antidiabetic drugs (OADs) for at least 3 months. METHODS: This multicenter, randomized, open-label, parallel-group, active-controlled, phase 3 study enrolled 362 participants with T2DM. Participants were stratified according to whether the insulin secretagogue (sulfonylurea or glinide) had been used before the screening and then randomized 1:1 to receive once-daily subcutaneous injections of HS-IDeg (n = 180) or NN-IDeg (n = 182) for 18 weeks. The primary endpoint was the change from baseline in glycated hemoglobin (HbA1c) to week 18. RESULTS: At week 18, the least squares (LS) mean change in HbA1c from baseline was -1.34% (95% CI -1.47 to -1.21) and -1.25% (95% CI -1.38 to -1.12) with HS-IDeg and NN-IDeg, respectively. The LS mean difference (HS-IDeg minus NN-IDeg) in HbA1c at week 18 was -0.09% (95% CI -0.28 to 0.10), demonstrating non-inferiority of HS-IDeg to NN-IDeg. Participants achieving HbA1c <7.0% at week 18 were 34.5% and 29.5% with HS-IDeg and NN-IDeg, respectively. Mean decreases in fasting plasma glucose and standard deviation of blood glucose were similar between both groups. Safety and tolerability, including hypoglycemia, adverse events, and weight change were similar between both groups. No severe hypoglycemia and no death occurred in the study. CONCLUSIONS: HS-IDeg and NN-IDeg demonstrated similar efficacy and safety over 18 weeks of treatment in Chinese patients with T2DM who had inadequate responses to OADs for at least 3 months.


Assuntos
Medicamentos Biossimilares , Diabetes Mellitus Tipo 2 , Hipoglicemiantes , Insulina de Ação Prolongada , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/sangue , Masculino , Pessoa de Meia-Idade , Feminino , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/uso terapêutico , Medicamentos Biossimilares/administração & dosagem , Medicamentos Biossimilares/efeitos adversos , Medicamentos Biossimilares/uso terapêutico , Insulina de Ação Prolongada/administração & dosagem , Insulina de Ação Prolongada/efeitos adversos , Insulina de Ação Prolongada/uso terapêutico , Idoso , Hemoglobinas Glicadas/análise , Adulto , Administração Oral , China , Resultado do Tratamento , Glicemia/efeitos dos fármacos , Glicemia/análise , Povo Asiático , População do Leste Asiático
14.
Biomaterials ; 298: 122133, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37146364

RESUMO

Liver fibrosis is a chronic disease without effective treatment in the clinic. Gene editing systems such as the well-known CRISPR/Cas9 have shown great potential in the biomedical field. However, the delivery of the ribonucleoprotein is challenging due to the unstable RNA probe and the requirement for the entrance to the nucleus. Recently, a structure-guided endonuclease (SGN) has been reported as an effective gene-editing system composed of a nuclease and stable DNA probes, which can regulate the protein expression by targeting specific mRNA outside the nucleus. Here, we conjugated the SGN to a nanomicelle as the delivery system. In the resulting material, the chance of the collision between the endonuclease and the probe was raised due to the confinement of the two components within the 40-nm nanomicelle, thus the mRNA can be cleaved immediately after being captured by the probe, resulting in a space-induced nucleotide identification-cleavage acceleration effect. The delivery system was used to treat liver fibrosis via the co-delivery of SGN and a drug rosiglitazone to the hepatic stellate cells, which separately downregulated the expression of tissue inhibitor of metalloprotease-1 and inactivated the hepatic stellate cells. The system successfully reversed the liver fibrosis in mice through the bidirectional regulatory that simultaneously promoted the degradation and inhibited the production of the collagen, demonstrating the great potency of the SGN system as gene medicine.


Assuntos
Sistemas CRISPR-Cas , Ribonucleoproteínas , Camundongos , Animais , Sistemas CRISPR-Cas/genética , Ribonucleoproteínas/genética , Ribonucleoproteínas/metabolismo , Preparações Farmacêuticas , Cirrose Hepática/tratamento farmacológico , Endonucleases/genética , Endonucleases/metabolismo , RNA Mensageiro
15.
Infect Drug Resist ; 16: 6017-6028, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37705511

RESUMO

Background: The prevalence of carbapenem-resistant hypervirulent Klebsiella pneumoniae (hv-CRKP) is a serious public threat globally. Here, we performed clinical, molecular, and phenotypic monitoring of hv-CRKP strains isolated from the intensive care unit (ICU) to offer evidence for prevention and control in hospitals. Methods: Data analysis of ICU patients suffering from ventilator-associated pneumonia (VAP) because of hv-CRKP infection, admitted at the Chinese Teaching Hospital between March 2019 and September 2021 was performed. Patients' antibiotic-resistance genes, virulence-associated genes, and capsular serotypes of these isolates were detected. Homology analysis of the strains was performed by MLST and PFGE. Six different strains were tested for their virulence traits using the serum killing test and the Galleria mellonella infection assay. For whole genome sequencing, KP3 was selected as a representative strain. Results: Clinical data of 19 hv-CRKP-VAP patients were collected and their hv-CRKP were isolated, including 10 of ST11-KL64, 4 of ST15-KL112, 2 of ST11-KL47, 1 of ST15-KL19, 1 of ST17-KL140, and 1 of ST48-KL62. Four ST15 and 8 ST11 isolates revealed high homology, respectively. Most strains carried the carbapenemase gene blaKPC-2 (14/19, 73.68%), followed by blaOXA-232 (4/19, 21.05%). All strains were resistant to almost all the antibiotics except polymyxin and tigacycline. Ten patients were treated with polymyxin or tigacycline based on their susceptibility results, and unfortunately 6 patients died. All strains exhibited a hyper-viscous phenotype, and the majority (17/19, 89.47%) of them contained rmpA and rmpA2. The serum killing test showed that KP9 was resistant to normal healthy serum, others were intermediately or highly sensitive. G. mellonella larvae infection assay suggested that the strains in this study were hypervirulent. Conclusion: This study highlights the dominant strain and molecular epidemiology of hv-CRKP in a hospital in China. We should pay more attention to the effect of hv-CRKP on VAP, strengthen monitoring and control transmission.

16.
Clin Pharmacokinet ; 62(3): 505-518, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36802026

RESUMO

AIM: To apply model-informed drug development (MIDD) approach to support the decision making in drug development and accelerate the clinical development of janagliflozin, an orally selective SGLT2 inhibitor. METHOD: We previously developed a mechanistic pharmacokinetic/pharmacodynamic (PK/PD) model of janagliflozin based on preclinical data to optimize dose design in the first-in-human (FIH) study. In the current study, we used clinical PK/PD data of the FIH study to validate the model and then simulate the PK/PD profiles of multiple ascending dosing (MAD) study in healthy subjects. Besides, we developed a population PK/PD model of janagliflozin to predict steady-state urinary glucose excretion (UGE [UGE,ss]) in healthy subjects in the Phase 1 stage. This model was subsequently used to simulate the UGE, ss in patients with type 2 diabetes mellitus (T2DM) based on a unified PD target (ΔUGEc) across healthy subjects and patients with T2DM. This unified PD target was estimated from our previous work of model-based meta-analysis (MBMA) for the same class of drugs. The model-simulated UGE,ss in patients with T2DM was validated by data from the clinical Phase 1e study. Finally, at the end of the Phase 1 study, we simulated the 24-week hemoglobin A1c (HbA1c) level in patients with T2DM of janagliflozin based on the quantitative UGE/FPG/HbA1c relationship informed by our previous MBMA study for the same class of drugs. RESULTS: The pharmacologically active dose (PAD) levels of multiple ascending dosing (MAD) study were estimated to be 25, 50,100 mg once daily (QD) for 14 days based on the effective PD target of approximately 50 g daily UGE in healthy subjects. Besides, our previous MBMA analysis for the same class of drugs has provided a unified effective PD target of ΔUGEc approximately 0.5-0.6 g/(mg/dL) in both healthy subjects and patients with T2DM. In this study, the model-simulated steady-state ΔUGEc (ΔUGEc,ss) of janagliflozin in patients with T2DM were 0.52, 0.61 and 0.66 g/(mg/dL) for 25, 50, 100 mg QD dose levels. Finally, we estimated that HbA1c at 24 weeks would decrease 0.78 and 0.93 from baseline for the 25 and 50 mg QD dose groups. CONCLUSIONS: The application of MIDD strategy adequately supported the decision making at each stage of janagliflozin development process. A waiver of Phase 2 study was successfully approved for janagliflozin based on these model-informed results and suggestions. This MIDD strategy of janagliflozin could be further utilized to support the clinical development of other SGLT2 inhibitors.


Assuntos
Diabetes Mellitus Tipo 2 , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hemoglobinas Glicadas , Hipoglicemiantes/farmacologia , Relação Dose-Resposta a Droga , Glicemia
17.
Regen Ther ; 24: 54-63, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37868719

RESUMO

Introduction: Clodronate-Liposomes (Clod-Lipo) injection after hematopoietic stem cell transplantation (HSCT) has been shown to be detrimental to hematopoietic reconstitution after transplantation, and our previous study showed that Clod-Lipo injection after HSCT increased adipocytes in the bone marrow cavity of mice after HSCT, but the reason for the large increase in adipocytes has not been clearly explained. The aim of this study was to investigate the source and mechanism of bone marrow cavity adipocytes after HSCT injection of Clod-Lipo. Methods: BALB/c mice received 7.5 Gy of total body irradiation followed by infusion of 5x106 bone marrow mononuclear cells from C57BL/6 via the tail vein. Clod-Lipo were injected through the tail vein on the first day after HSCT and every 5 days for the rest of the day. BALB/c mice were then divided into three groups: BMT, BMT + Clodronate-Liposomes (BMT + Clod-Lipo), and BMT + PBS-Liposomes (BMT + PBS-Lipo). Bone marrow pathological changes were detected by H&E staining, Western blot was used to detect the expression of NLRP3 and Caspase-1 in mouse bone marrow cells, and RT-qPCR was used to detect the expression levels of the key transcription factors peroxisome proliferator-activated receptor γ (PPAR-γ) and CCAAT/enhancer binding protein (C/EBPα) mRNA in bone marrow cells. Mouse mesenchymal stem cells (MSC) cultured in vitro were identified by flow cytometry, and adipocyte induction assays were performed using Clod-Lipo action for 24 h, Oil red staining was used to identify adipogenesis. Western blot was performed to detect NLRP3 and caspase-1 expression in MSC after Clod-Lipo action. Caspase-1 was blocked with Ac-YVAD-cmk (Ac-YV), followed by adipogenesis assay after 24 h of Clod-Lipo action to observe the change in the amount of adipogenesis. Results: Compared with the other two groups, a significant increase in adipocytes was found in the Clod-Lipo group by HE staining, and increased expression of NLRP3 and Caspase-1 in mouse bone marrow cells was found by western Blot. By culturing MSC in vitro and performing adipogenesis assay after 24 h of Clod-Lipo action, it was found that adipogenesis was increased in the Clod-Lipo group, while the expression of NLRP3 and Caspase-1 was increased in MSCs, and adipogenesis assay was performed after 2 h of action using Caspase-1 inhibitor, and it was found that adipocytes was reduced. Conclusions: The results of this study suggest that MSC are biased towards adipocyte generation in response to Clod-Lipo, a process that may be associated with activation of the NLRP3/caspase-1 pathway.

18.
Clin Pharmacokinet ; 62(8): 1093-1103, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37284974

RESUMO

BACKGROUND: Janagliflozin is a novel sodium-glucose cotransport-2 inhibitor. Despite its remarkable effect in glycemic control, no systematic research has evaluated the effect of renal impairment (RI) on its pharmacokinetics and pharmacodynamics. METHODS: Here, patients with T2DM (n = 30) were divided into normal renal function (eGFR ≥ 90 mL/min/1.73 m2), mild RI (eGFR between 60 and 89 mL/min/1.73 m2), moderate RI-I (eGFR between 45 and 59 mL/min/1.73 m2), and moderate RI-II (eGFR between 30 and 44 mL/min/1.73 m2) groups. They were administered 50 mg janagliflozin orally, and plasma and urine samples were collected for the determination of janagliflozin concentration. RESULTS: Following oral administration, janagliflozin was rapidly absorbed, with the time to Cmax of 2-6 h for janagliflozin and 3-6 h for its metabolite XZP-5185. Plasma exposure levels were similar for janagliflozin in T2DM patients with or without RI but decreased for the metabolite XZP-5185 in T2DM patients with eGFR between 45 and 89 mL/min/1.73 m2. Janagliflozin significantly promoted the excretion of urinary glucose, even in patients with reduced eGFR. Janagliflozin was well tolerated in patients with T2DM with or without RI, and no serious adverse events (SAEs) occurred during this trial. CONCLUSIONS: The exposure levels of janagliflozin in T2DM patients were slightly increased with worsening of RI (i.e., 11% increase in the AUC in patients with moderate RI compared with the normal renal function group). Despite worsening of renal function, janagliflozin exerted a significant pharmacologic effect and was well tolerated, even in patients with moderate RI, implying a promising role in the treatment of patients with in T2DM. REGISTRATION: China Drug Trial register ( http://www.chinadrugtrials.org.cn/I ) identifier no.: CTR20192721.


Assuntos
Diabetes Mellitus Tipo 2 , Insuficiência Renal , Xilitol , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , População do Leste Asiático , Glucose/metabolismo , Insuficiência Renal/complicações , Xilitol/análogos & derivados , Xilitol/farmacocinética
19.
J Phys Chem B ; 126(26): 4828-4839, 2022 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-35736566

RESUMO

As a type I viral fusion protein, SARS-CoV-2 spike undergoes a pH-dependent switch to mediate the endosomal positioning of the receptor-binding domain to facilitate viral entry into cells and immune evasion. Gaps in our knowledge concerning the conformational transitions and key intramolecular motivations have hampered the development of effective therapeutics against the virus. To clarify the pH-sensitive elements on spike-gating the receptor-binding domain (RBD) opening and understand the details of the RBD opening transition, we performed microsecond-time scale constant pH molecular dynamics simulations in this study. We identified the deeply buried D571 with a clear pKa shift, suggesting a potential pH sensor, and showed the coupling of ionization of D571 with spike RBD-up/down equilibrium. We also computed the free-energy landscape for RBD opening and identified the crucial interactions that influence RBD dynamics. The atomic-level characterization of the pH-dependent spike activation mechanism provided herein offers new insights for a better understanding of the fundamental mechanisms of SARS-CoV-2 viral entry and infection and hence supports the discovery of novel therapeutics for COVID-19.


Assuntos
COVID-19 , SARS-CoV-2 , Enzima de Conversão de Angiotensina 2 , Humanos , Concentração de Íons de Hidrogênio , Simulação de Dinâmica Molecular , Ligação Proteica , Domínios Proteicos , Glicoproteína da Espícula de Coronavírus/química
20.
Int J Lab Hematol ; 42(5): 612-618, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32573949

RESUMO

INTRODUCTION: Microscopy has been recognized as the "gold-standard" cellular analysis of serous cavity effusion. However, this method is time-consuming, labor-intensive, and requires accomplished skills. Here, we investigated the efficiency of hematology analyzer in screening malignant cells in serous cavity effusion. METHODS: A total of 991 serous cavity effusion samples and 370 validation specimens collected from different departments were sent to the clinical laboratory for routine cell count using the automated hematology body fluid (BF) mode and exfoliative cytology simultaneously. High-fluorescent cells (HFCs) were measured as the relative count (HF%) and absolute count (HF#) by BF mode. Receiver operating characteristic curve analysis was combined with scattergram rules to screen malignant cells. RESULTS: HF# and HF% in malignant samples (subgroup) were significantly higher than those in benign samples, and the HF# and HF% levels were different between ascites and pleural effusion (PE). The area under the curve values were also different between ascites and PE. Positive of malignant cells was very high when the ascites or PE sample touching Rule 1 positive and either Rule 2 negative or positive. The cutoff levels of HF# were 5.5 HFC/µL on the basis of Rules 1 and 2 negative, whereas 83.5 HFC/µL on the basis of Rule 1 negative but Rule 2 positive in ascites. By contrast, the cutoff levels of HF% were 0.55 HFC/100 WBC on the basis of Rules 1 and 2 negative, whereas 4.95 HFC/100 WBC on the basis of Rule 1 negative but Rule 2 positive in PE. CONCLUSIONS: Serous cavity effusion will be increasingly analyzed using the automated hematology analyzer BF mode in the future because of its rapidness and convenience. The combined application of HFC with scattergram rules is a feasible and useful approach to screen malignant cells in serous cavity effusion.


Assuntos
Líquidos Corporais , Citodiagnóstico/métodos , Citometria de Fluxo/métodos , Biópsia Líquida/métodos , Neoplasias/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Automação Laboratorial , Criança , Citodiagnóstico/normas , Detecção Precoce de Câncer/métodos , Detecção Precoce de Câncer/normas , Feminino , Citometria de Fluxo/normas , Imunofluorescência , Humanos , Biópsia Líquida/normas , Masculino , Microscopia/métodos , Pessoa de Meia-Idade , Curva ROC , Reprodutibilidade dos Testes , Adulto Jovem
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