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1.
J Clin Immunol ; 44(5): 124, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38758476

RESUMO

PURPOSES: STAT1 is a transduction and transcriptional regulator that functions within the classical JAK/STAT pathway. In addition to chronic mucocutaneous candidiasis, bacterial infections are a common occurrence in patients with STAT1 gain-of-function (GOF) mutations. These patients often exhibit skewing of B cell subsets; however, the impact of STAT1-GOF mutations on B cell-mediated humoral immunity remains largely unexplored. It is also unclear whether these patients with IgG within normal range require regular intravenous immunoglobulin (IVIG) therapy. METHODS: Eleven patients (harboring nine different STAT1-GOF mutations) were enrolled. Reporter assays and immunoblot analyses were performed to confirm STAT1 mutations. Flow cytometry, deep sequencing, ELISA, and ELISpot were conducted to assess the impact of STAT1-GOF on humoral immunity. RESULTS: All patients exhibited increased levels of phospho-STAT1 and total STAT1 protein, with two patients carrying novel mutations. In vitro assays showed that these two novel mutations were GOF mutations. Three patients with normal total IgG levels received regular IVIG infusions, resulting in effective control of bacterial infections. Four cases showed impaired affinity and specificity of pertussis toxin-specific antibodies, accompanied by reduced generation of class-switched memory B cells. Patients also had a disrupted immunoglobulin heavy chain (IGH) repertoire, coupled with a marked reduction in the somatic hypermutation frequency of switched Ig transcripts. CONCLUSION: STAT1-GOF mutations disrupt B cell compartments and skew IGH characteristics, resulting in impaired affinity and antigen-specificity of antibodies and recurrent bacterial infections. Regular IVIG therapy can control these infections in patients, even those with normal total IgG levels.


Assuntos
Linfócitos B , Infecções Bacterianas , Mutação com Ganho de Função , Imunoglobulinas Intravenosas , Fator de Transcrição STAT1 , Humanos , Fator de Transcrição STAT1/genética , Infecções Bacterianas/imunologia , Infecções Bacterianas/genética , Feminino , Masculino , Criança , Imunoglobulinas Intravenosas/uso terapêutico , Linfócitos B/imunologia , Adulto , Imunoglobulina G/imunologia , Imunoglobulina G/sangue , Pré-Escolar , Adolescente , Adulto Jovem , Imunidade Humoral
2.
Inorg Chem ; 63(7): 3467-3476, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38306402

RESUMO

The energy gap and conduction band position of catalysts play crucial roles in solar-to-hydrogen (STH) transformation technology. Unfortunately, although an increase in the conduction band position can effectively promote the photoreduction capacity of the photocatalyst, it will inevitably widen the band gap, thus reducing the light-absorption scale. It seems that there is a contradiction between the reduction of band gap and the improvement of conduction band position, which is that "You can't have your cake and eat it too." Herein, an ultrasimple molecular adsorption strategy was engineered by adsorbing hydrazine hydrate on the surface of TiO2. The theoretical and experimental results indicated that the strong electron-donating effect of amino groups in hydrazine hydrate can promote the redistribution of photogenerated electrons and form surface electron networks on the surface of TiO2 photocatalysts, which can bend the conduction band upward and significantly improve its photoreduction ability. Besides, the adsorption of -NH2 can narrow the band gap width of TiO2 and promote the separation efficiency of photogenerated carriers. More interestingly, it can also effectively enhance the adsorption of H2O and H+, thus greatly elevating the STH efficiency. The STH rate of the as-prepared T-N-3 can be increased by ≈530%. This work sheds light on a new approach for resolving the contradiction between photoreduction and light absorption capabilities to effectively enhance photocatalytic performance.

3.
BMC Neurol ; 24(1): 175, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38789928

RESUMO

BACKGROUND: Acute ischemic stroke (AIS) is one of the most common cerebrovascular diseases which accompanied by a disruption of aminothiols homeostasis. To explore the relationship of aminothiols with neurologic impairment severity, we investigated four aminothiols, homocysteine (Hcy), cysteine (Cys), cysteinylglycine (CG) and glutathione (GSH) in plasma and its influence on ischemic stroke severity in AIS patients. METHODS: A total of 150 clinical samples from AIS patients were selected for our study. The concentrations of free reduced Hcy (Hcy), own oxidized Hcy (HHcy), free reduced Cys (Cys), own oxidized Cys (cysteine, Cyss), free reduced CG (CG) and free reduced GSH (GSH) were measured by our previously developed hollow fiber centrifugal ultrafiltration (HFCF-UF) method coupled with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The concentration ratio of Hcy to HHcy (Hcy/HHcy), Cys to Cyss (Cys/Cyss) were also calculated. The neurologic impairment severity of AIS was evaluated using National Institutes of Health Stroke Scale (NIHSS). The Spearman correlation coefficient and logistic regression analysis was used to estimate and perform the correlation between Hcy, HHcy, Cys, Cyss, CG, GSH, Hcy/HHcy, Cys/Cyss and total Hcy with NIHSS score. RESULTS: The reduced Hcy and Hcy/HHcy was both negatively correlated with NIHSS score in AIS patients with P = 0.008, r=-0.215 and P = 0.002, r=-0.249, respectively. There was no significant correlation of Cys, CG, GSH, HHcy, Cyss, Cys/Cyss and total Hcy with NIHSS score in AIS patients with P value > 0.05. CONCLUSIONS: The reduced Hcy and Hcy/HHcy, not total Hcy concentration should be used to evaluate neurologic impairment severity of AIS patient.


Assuntos
Cisteína , Glutationa , Homocisteína , AVC Isquêmico , Oxirredução , Índice de Gravidade de Doença , Humanos , Masculino , Feminino , AVC Isquêmico/sangue , AVC Isquêmico/diagnóstico , Homocisteína/sangue , Idoso , Pessoa de Meia-Idade , Cisteína/sangue , Glutationa/sangue , Dipeptídeos/sangue , Idoso de 80 Anos ou mais
4.
Gen Physiol Biophys ; 43(2): 153-162, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38477605

RESUMO

Endothelial damage caused by persistent glucose and lipid metabolism disorders is the main reason of diabetic vascular diseases. Daidzein exerts positive effects on vascular dysfunction. Peroxisome proliferator-activated receptors (PPARs) regulate critically glucose and lipid metabolism. However, the interaction of daidzein to PPARs is still insufficiently explored. In this study, the cell proliferation was detected by EdU. The intrinsic activity and binding affinity of daidzein for human PPARs (hPPARs) were estimated by transactivation reporter gene test and HPLC-UV method, respectively. Daidzein significantly reversed high glucose (HG, at 30 mmol/l)-induced injury in HUVECs, which was inhibited by both PPARα and PPARγ antagonist, but no PPARß antagonist. Daidzein selectively activated hPPARα and hPPARγ1, but weakly hPPARß. Additionally, daidzein also bound to both hPPARα and hPPARγ1. The findings suggested that daidzein may be a PPARα and PPARγ dual-agonist. The amelioration of daidzein on HUVECs from hyperglycemia may be mediated by the activation of PPARα and PPARγ receptors.


Assuntos
Isoflavonas , PPAR alfa , PPAR gama , Humanos , PPAR alfa/metabolismo , Células Endoteliais , Glucose
5.
Anal Biochem ; 677: 115265, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37499894

RESUMO

For patients receiving organ transplants, monitoring the blood concentration of MPA can provide timely information on whether MPA has reached the effective therapeutic window to better function while reducing the incidence of rejection or adverse reactions. In this study, an electrochemical sensor for the detection of MPA was built using a nanocomposite made of CS-MWCNT and AuNPs. At the same time, the high performance liquid phase (HPLC) method for MPA was established and compared with this sensor. The surface morphology, structure, and roughness of the material on the electrode were characterized by scanning electron microscopy (SEM), Fourier transforms infrared spectroscopy (FTIR), and atomic force microscopy (AFM). In addition, the electrochemical behavior of the modified electrode was characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The standard curve was obtained in blank plasma, not pure buffer solution. The peak current was linearly related to the MPA concentration in the linear range of 0.001-0.1 mM with a detection limit of 0.05 µM and good anti-interference ability. Moreover, the sensor was employed with success for the determination of MPA in rat plasma with good recovery. The electrochemical sensor presented here is eco-friendly, and sensitive, and offers a great possibility for practical applicability.


Assuntos
Nanopartículas Metálicas , Ácido Micofenólico , Animais , Ratos , Ouro/química , Técnicas Eletroquímicas/métodos , Nanopartículas Metálicas/química , Espectroscopia Dielétrica , Eletrodos , Limite de Detecção
6.
Mikrochim Acta ; 190(12): 484, 2023 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-38006440

RESUMO

Developing an intelligent, sensitive, and visual strategy for quickly identifying anthrax biomarkers is crucial for ensuring food safety and preventing disease outbreaks. Herein, a smartphone-integrated ratiometric fluorescent sensing platform based on bimetallic metal-organic framework (Eux/Tb1-x-MOF) nanowires was designed for specific recognition of pyridine-2,6-dicarboxylic acid (DPA, anthrax biomarker). The Eux/Tb1-x-MOF was prepared by coordinating Eu3+ and Tb3+ with BBDC ligands, which exhibited a uniform fibrous morphology and dual-emission fluorescence at 543 and 614 nm. After the introduction of DPA, the red emission at 614 nm displayed obvious fluorescence quenching, while the green emission at 543 nm was gradually enhanced. The ratiometric sensing offered a wide linear equation in the range of 0.06-15 µg/mL and a low detection limit (LOD) of 20.69 ng/mL. Furthermore, a portable smartphone installing the color recognition application can achieve sensitive, real-time, and visual detection of DPA. As a simple and effective smartphone-assisted sensing platform, this work holds admirable promise to broaden the applications in biomarker real-time determinations and other fields.


Assuntos
Antraz , Estruturas Metalorgânicas , Nanofios , Humanos , Antraz/diagnóstico , Fluorescência , Corantes Fluorescentes , Smartphone , Biomarcadores
7.
Lab Invest ; 102(8): 872-884, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35361881

RESUMO

Lupus nephritis (LN) is associated with extensive injury and nephron loss in the afflicted kidney. Evidence has revealed the involvement of dysregulated Yin Yang 1 (YY1), a reported inflammatory modulator, in LN-induced kidney injury, and our microarray profile identified downregulated YY1 expression. Therefore, this study explored the functional relevance and mechanism of YY1 in LN-induced kidney injury. LN was modeled in mice by intraperitoneal injection of pristane, and Jurkat cells (CD41 human T lymphocytes) were activated with TNF-α to mimic the inflammatory environment found in LN. The expression patterns of YY1 and bioinformatics predictions of the downstream factor IFN-γ were confirmed in renal tissues from the mice with LN using qRT-PCR and Western blot analyses. The contents of proinflammatory cytokines in mouse serum samples and cell supernatants were determined using enzyme-linked immunosorbent assays (ELISAs). Ectopic expression and depletion approaches were subsequently used in vitro and in vivo to examine the effects of the YY1/IFN-γ/Fra2/PARP-1/FOXO1 axis on TNF-α-induced inflammation and LN-induced kidney injury. The results showed downregulated expression of YY1 and FOXO1 in the kidney tissues of the mice with LN. Increased proinflammatory factor production was observed in the mice with LN and TNF-α-treated Jurkat cell supernatant, accompanied by increased cell apoptosis and a high ratio of Th17/Treg cells, and these effects were reversed by YY1 restoration. YY1 was further shown to inhibit IFN-γ expression and thereby downregulate Fra2 expression. Fra2 depletion then inhibited PARP-1 expression and promoted FOXO1 expression to suppress cell apoptosis and the release of inflammatory factors. Collectively, our findings revealed that YY1 may alleviate LN-induced renal injury via the IFN-γ/Fra2/PARP-1/FOXO1 axis.


Assuntos
Rim , Nefrite Lúpica , Linfócitos T Reguladores , Células Th17 , Fator de Transcrição YY1 , Animais , Proteína Forkhead Box O1 , Humanos , Interferon gama/metabolismo , Rim/metabolismo , Rim/patologia , Nefrite Lúpica/metabolismo , Camundongos , Poli(ADP-Ribose) Polimerase-1 , Linfócitos T Reguladores/citologia , Células Th17/citologia , Fator de Necrose Tumoral alfa/metabolismo , Fator de Transcrição YY1/genética , Fator de Transcrição YY1/metabolismo
8.
Biomed Chromatogr ; 36(10): e5435, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35763335

RESUMO

The study of brain diseases has long been of interest to researchers worldwide, and stroke is the third leading cause of death that threatens human health. At the same time, cerebral ischemia-reperfusion injury is closely associated with high rates of disability and mortality. The conditions of the 6-aminoquinolyl N-hydroxysccinimidyl carbamate method for the derivatization of amino acids in the bone marrow fluid and hippocampus of C57BL/6 mice with cerebral ischemia-reperfusion injury were explored and optimized, such as the column temperature, concentration of derivatization reagents and mobile phase concentration. The mobile phase consisted of 20 mm sodium acetate solution (phosphoric acid to adjust pH 5.0) and 60% acetonitrile solution at a flow rate of 1 ml min-1 . The 23 analytes were separated and determined in a gradient elution procedure; the correlation coefficient r was >0.9990 in the range 0.1-8.0 µg ml-1 . The results showed that the content of relevant analytes was significantly changed in the cerebral ischemia-reperfusion injury model, and the method was suitable for the simultaneous determination of 23 amino acids in the bone marrow fluid and hippocampus of C57BL/6 mice.


Assuntos
Medula Óssea , Traumatismo por Reperfusão , Aminoácidos , Aminoquinolinas , Animais , Cromatografia Líquida de Alta Pressão/métodos , Hipocampo , Humanos , Indicadores e Reagentes , Camundongos , Camundongos Endogâmicos C57BL
9.
Biomed Chromatogr ; 35(6): e5084, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33559223

RESUMO

Emerging evidence suggests that amino acid (AA) neurotransmitters play important roles in the pathophysiological processes of cerebral ischemia. In this work, an HPLC with fluorescence detection (HPLC-FLR) method was developed for the simultaneous determination of 18 AAs in the cortex and plasma after cerebral ischemia in mice. The ischemia model was prepared by bilateral common carotid artery occlusion, and then the cortex and plasma of the sham, ischemia, and naringenin groups were collected. Based on the protein precipitation method, a simple and effective sample preparation method was developed. The treated sample contained minimal proteins and lipids. The analysis of the sample was performed by the proposed HPLC-FLR method in combination with o-phthalaldehyde. The results showed a statistically significant increase in excitatory AAs (aspartic acid and glutamic acid), inhibitory AAs (glycine and 4-aminobutyric acid), phenylalanine, citrulline, isoleucine, and leucine levels, and a decrease of glutathione and phenylalanine levels when compared with the sham group in the cortex. Besides, the administration of naringenin had significant effects on excitatory AAs, inhibitory AA (glycine), glutamine, tyrosine, phenylalanine, and leucine levels when compared with the sham group in the cortex. These findings could be utilized in studying and clarifying the mechanisms of ischemia.


Assuntos
Aminoácidos/sangue , Isquemia Encefálica/metabolismo , Córtex Cerebral/química , Animais , Biomarcadores/sangue , Cromatografia Líquida de Alta Pressão , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurotransmissores/sangue
10.
Biomed Chromatogr ; 34(3): e4767, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31785600

RESUMO

Disorders of certain branched-chain amino acids may be associated with the occurrence and development of non-alcoholic fatty liver disease. Measurement of related branched-chain amino acid levels could provide a reference for the clinical and scientific research of the non-alcoholic fatty liver disease. An established HPLC-FLD method was used to quantify aspartic acid, glutamate, glutamine, glycine, taurine, tyrosine, 4-amino butanoic acid, tryptophan, methionine, valine, phenylalanine, isoleucine and leucine in mouse brain tissue. Brain tissue samples mixed with internal standard (3-aminobutyric acid) were processed, then derivatized with 2-O-phthaldialdehyde, and finally separated on an ODS2 column through gradient elution at a flow rate of 1.0 ml·min-1 . The excitation and emission wavelengths were set at 340 and 455 nm, respectively. The mobile phase A was 100% methanol and the mobile phase B consisted of 30 mmol·L-1 sodium acetate (pH 6.8). The injection volume was 20 µl and the single run time was 45 min. Several parameters, accuracy, precision, and stability, were verified and the results showed the established method had good sensitivity and resolution for all of the 13 compounds and internal standard in mouse brain.


Assuntos
Aminoácidos/análise , Aminobutiratos/análise , Encéfalo/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Aminoácidos/metabolismo , Animais , Química Encefálica/fisiologia , Limite de Detecção , Modelos Lineares , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Reprodutibilidade dos Testes , Espectrometria de Fluorescência
11.
Biomed Chromatogr ; 32(11): e4338, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30003560

RESUMO

The determination of amino acids and monoamine with actions like neurotransmitters or modulators has become increasingly important for studying the relationship between the dysfunction of neurotransmitters and the pathogenesis of diabetic encephalopathy. Here, a high-performance liquid chromatography with fluorescence detection method was developed to simultaneously determine nine monoamines and amino acids including three excitatory neurotransmitters (aspartate, glutamate, and serotonin), four inhibitory neurotransmitters (glycine, γ-aminobutyric acid, taurine, dopamine), a precursor of 5-HT (tryptophan) and methionine using homoserine as the internal standard. The separation was performed on a BDS column with methanol-buffer solution of 35 mmol/L sodium acetate and 5 mmol/L citric acid (pH 6.0) using a simple gradient elution. Several parameters including specificity, precision, and recovery were validated after optimization of the analytical conditions. The developed method was successfully applied to determine the cortex and the hippocampus samples from Sprague-Dawley rats. Our results showed that various neurotransmitters involved in diabetes mellitus may tend to be differentially modulated and present a different alteration tendency at different time course, which might be associated with the duration of diabetes mellitus.


Assuntos
Encefalopatias/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Complicações do Diabetes/metabolismo , Aminoácidos Excitatórios/análise , Hipocampo/metabolismo , Neurotransmissores/análise , Animais , Limite de Detecção , Modelos Lineares , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes
12.
Biomed Chromatogr ; 31(8)2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28097679

RESUMO

The determination of amino acids with actions like neurotransmitters or modulators has been increasingly important for diagnosis in many neuropsychiatric diseases. A rapid and simple high-performance liquid chromatography with fluorescence detection method was developed for simultaneous determination of seven amino acids: aspartate (Asp), glutamate (Glu), serine (Ser), glutamine (Gln), glycine (Gly), taurine (Tau) and γ-aminobutyric` acid (GABA). Homoserine was used as an internal standard. The analysis was performed on a BDS column with methanol and 50 mm sodium acetate solution (pH 6.5) using a simple gradient elution. Several parameters of the developed method were validated including linearity, accuracy, precision, extraction recovery and stability, which were within the acceptable range. The method was successfully applied to determination of real samples: hippocampus and cortex in depressed rats exposed to chronically unpredictable stress in order to study if there existed differences in the seven amino acids levels between depressed rats and control. The results showed that Asp, Gly, Tau and GABA significantly decreased with increasing Gln in the hippocampus of depressed rats, compared with that of the control group, among which obviously lower level of Asp and higher level of Gln in cortex were observed. The analytical method and the results could be useful for clinical diagnosis and further insight into pathophysiological mechanism of depression.


Assuntos
Aminoácidos/análise , Química Encefálica , Cromatografia Líquida de Alta Pressão/métodos , Depressão/patologia , Hipocampo/patologia , Neurotransmissores/análise , Animais , Limite de Detecção , Masculino , Ratos , Ratos Sprague-Dawley
13.
Ther Drug Monit ; 37(6): 776-82, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26035137

RESUMO

BACKGROUND: Free drug analysis is increasingly becoming popular in therapeutic drug monitoring (TDM). Centrifugal ultrafiltration (CF-UF) is the primary method to separate free drug from that of bound drug. However, the volume ratio of ultrafiltrate to sample solution (Vu/Vs) affects the accuracy of CF-UF, which highly depends on the different plasma conditions. Plasma protein concentrations in patients are different from those observed in healthy subjects, and there are also significant differences among patients with different diseases. Only very few studies have reported on the effect of protein concentration on the analysis methodology of free drug by CF-UF. METHODS: In this study, valproic acid was used as the representative drug, and plasma samples with different albumin concentrations were analyzed by CF-UF and hollow fiber centrifugal ultrafiltration (HFCF-UF). RESULTS: There was no significant difference of free drug concentrations by HFCF-UF and CF-UF when plasma albumin concentrations ranged 40-60 g/L. However, at low albumin concentrations (<40 g/L), a considerable difference was detected, and the difference was increased with the decrease of plasma albumin concentration. When the albumin concentration was as low as 10 g/L, the free drug concentration was 17.3 mcg/mL by CF-UF, whereas it was 10.2 mcg/mL by HFCF-UF. CONCLUSIONS: The accuracy of free drug measurement by CF-UF was albumin concentration dependent. However, such an effect was not observed when samples were prepared by HFCF-UF, which was more suitable for TDM of plasma samples from different patients. Therefore, this method could be readily applied to the measurement of free valproic acid plasma concentrations for TDM in patients.


Assuntos
Monitoramento de Medicamentos/métodos , Albumina Sérica/metabolismo , Ultrafiltração/métodos , Ácido Valproico/farmacocinética , Adolescente , Adulto , Idoso , Centrifugação/métodos , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Adulto Jovem
14.
Chirality ; 27(3): 235-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25545065

RESUMO

A high-performance liquid chromatography (HPLC) method was established to detect Xeljanz enantiomers in active pharmaceutical ingredients (APIs) and tablets. The separation was achieved on a Chiralpak IC column using a mobile phase of hexane-ethanol-diethylamine (65:35:0.1, v/v). The detection wavelength was 289 nm. The peak areas and the enantiomer concentrations in the range of 0.15-2.25 µg•mL(-1) were in high linearity, with correlation coefficients higher than 0.999. The recoveries were 86.44% at the concentrations of 7.5, 18.75, and 37.5 µg•mL(-1) . The limit of detection (LOD) and limit of quantification (LOQ) were 0.042 and 0.14 µg•mL(-1) , respectively. This HPLC method is suitable for detecting the enantiomers of Xeljanz in its APIs and tablets.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Dietilaminas/análise , Janus Quinase 3/antagonistas & inibidores , Piperidinas/análise , Inibidores de Proteínas Quinases/análise , Pirimidinas/análise , Pirróis/análise , Estereoisomerismo , Comprimidos
15.
Acta Psychol (Amst) ; 246: 104282, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38642451

RESUMO

This study examines why and when proactive employees share knowledge. By integrating the Motivation-Opportunity-Ability Framework and Trait Activation Theory, and incorporating Mindsponge Theory, our multi-level model proposed that job autonomy moderates the impact of proactive personality on knowledge sharing (KS) within and between teams. Transformational leadership exhibits a cross-level effect on job autonomy. Utilizing a two-source, three-time-point research design, we collected data from 63 team leaders and 241 team members across six Chinese companies. Multilevel regression analysis revealed that within teams, increased job autonomy coupled with a proactive personality significantly enhanced KS. Between teams, job autonomy had a positive moderating effect. When job autonomy was low, more proactive teams exhibited less KS, whereas this negative effect was mitigated when job autonomy was high. The cross-level effect of transformational leadership on job autonomy was demonstrated. The theoretical and practical implications of these findings are discussed.


Assuntos
Liderança , Humanos , Masculino , Feminino , Adulto , Personalidade/fisiologia , Motivação , Emprego , Disseminação de Informação , China , Pessoa de Meia-Idade
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 310: 123942, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38277783

RESUMO

Gefitinib, a highly significant antitumor drug, is now commonly employed in clinical settings as a first-line treatment for patients with advanced or metastatic non-small cell lung cancer, colon cancer, and breast cancer. Herein, a convenient, rapid, and accurate fluorescence method based on nitrogen-doped carbon dots (NCDs) was designed for ultrasensitive detection of gefitinib. The NCDs were easily synthesized through one-pot hydrothermal process using p-phenylenediamine and D-glutamic acid as the precursors. The sensing strategy relied on the fluorescence of NCDs at 345 nm, which was selectively reduced by gefitinib based on the inner filter effect (IFE). With a broad linear range of 0.025-30 µg/mL and a low limit of detection of 5.5 ng/mL, the probe was successfully applied to the detection of gefitinib in human serum samples, demonstrating strong practicality, affordability, and high accuracy. The proposed sensor is simple in design, fast in detection and cost-effective, and exhibits promising application in drug real-time analysis.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Pontos Quânticos , Humanos , Gefitinibe , Carbono , Nitrogênio , Neoplasias Pulmonares/tratamento farmacológico , Espectrometria de Fluorescência/métodos , Corantes Fluorescentes
17.
J Chromatogr Sci ; 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38493310

RESUMO

The concentration of mitoxantrone in the blood of mice was determined by a high-performance liquid chromatography-ultraviolet method with aloe-emodin as the internal standard. The separation was performed on a Hypersil BDS2 column (4.6 × 250 mm, 5 µm) as the analytical column, the mobile Phase A was acetonitrile, and B was 20-mM potassium dihydrogen phosphate (adding 1% triethylamine and adjusting the pH to 2.8 with phosphoric acid) and 4.6-mM sodium octyl sulfonate. The flow rate was 1.0 mL·min-1, the detection wavelength was 243 nm, the column temperature is 25 ± 5°C and the injection amount was 20 µL. Finally, the linear range of mitoxantrone was 5-200 µg·mL-1, and the correlation coefficient was r = 0.9999. The recovery rate of the method was 91.93-105.5%, and the extraction recovery rate was 91.45-105.5%. The intraday precision and interday precision were <3.29% (limit of detection = 0.3 µg·mL-1). The HPLC method established in this paper was simple, rapid, sensitive and accurate, and can be used to determine the content of mitoxantrone in mouse plasma after tail vein injection.

18.
Chemosphere ; 346: 140664, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37949191

RESUMO

A novel ZnO/BiOCOOH microsphere photocatalyst with a type-Ⅱ mechanism was developed for the first time. This strategy was accomplished by immobilizing ZnO onto 3D BiOCOOH microspheres via a single-step hydrothermal synthesis method. The ability to degrade tetracycline (TC) in water under visible light and inactivate bacteria of as-catalyst were analyzed. Among the prepared samples, the ZnO/BiOCOOH composite, with a mass ratio of 40%(Zn/Bi), exhibited the highest photocatalytic activity, which was able to degrade 98.22% of TC in just 90 min and completely eradicated Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) in 48 h, and had potential application in solving water resource environmental pollution. The photoelectric characteristics of the photocatalysts were examined by means of electrochemical impedance spectroscopy (EIS) and photoluminescence (PL) spectroscopy. The findings indicated that the superior photocatalytic performance could be credited to the dissociation of electrons (e-) and holes (h+) in heterojunction composites. Finally, electron paramagnetic resonance (EPR) and capture experiments were conducted to confirm the photocatalytic mechanism of the type-Ⅱ heterojunction. This work provides a new Bi-base photocatalyst for aqueous environmental control.


Assuntos
Compostos Heterocíclicos , Óxido de Zinco , Microesferas , Escherichia coli , Staphylococcus aureus , Tetraciclina/farmacologia , Antibacterianos/farmacologia , Bactérias , Luz , Água , Catálise
19.
Exp Neurol ; 378: 114822, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38823676

RESUMO

Post-stroke depression (PSD) is a complication of cerebrovascular disease, which can increase mortality after stroke. CRH is one of the main signaling peptides released after activation of the hypothalamic-pituitary-adrenal (HPA) axis in response to stress. It affects synaptic plasticity by regulating inflammation, oxidative stress and autophagy in the central nervous system. And the loss of spines exacerbates depression-like behavior. Therefore, synaptic deficits induced by CRH may be related to post-stroke depression. However, the underlying mechanism remains unclear. The Keap1-Nrf2 complex is one of the core components of the antioxidant response. As an autophagy associated protein, p62 participates in the Keap1-NrF2 pathway through its Keap1 interaction domain. Oxidative stress is involved in the feedback regulation between Keap1-Nrf2 pathway and p62.However, whether the relationship between CRH and the Keap1-Nrf2-p62 pathway is involved in PSD remains unknown. This study found that serum levels of CRH in 22 patients with PSD were higher than those in healthy subjects. We used MCAO combined with CUMS single-cage SD rats to establish an animal model of PSD. Animal experiments showed that CRHR1 antagonist prevented synaptic loss in the hippocampus of PSD rats and alleviated depression-like behavior. CRH induced p62 accumulation in the prefrontal cortex of PSD rats through CRHR1. CRHR1 antagonist inhibited Keap1-Nrf2-p62 pathway by attenuating oxidative stress. In addition, we found that abnormal accumulation of p62 induces PSD. It alleviates depression-like behavior by inhibiting the expression of p62 and promoting the clearance of p62 in PSD rats. These findings can help explore the pathogenesis of PSD and design targeted treatments for PSD.


Assuntos
Depressão , Ratos Sprague-Dawley , Receptores de Hormônio Liberador da Corticotropina , Acidente Vascular Cerebral , Animais , Ratos , Masculino , Depressão/etiologia , Depressão/tratamento farmacológico , Depressão/metabolismo , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/psicologia , Acidente Vascular Cerebral/metabolismo , Receptores de Hormônio Liberador da Corticotropina/antagonistas & inibidores , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Humanos , Regulação para Baixo/efeitos dos fármacos , Pessoa de Meia-Idade , Modelos Animais de Doenças , Feminino , Idoso , Proteína Sequestossoma-1/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/antagonistas & inibidores , Fator 2 Relacionado a NF-E2/metabolismo , Hormônio Liberador da Corticotropina/metabolismo
20.
Analyst ; 138(24): 7369-75, 2013 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-24165752

RESUMO

In human plasma, the total concentration of non-protein binding (NPB) drugs is equal to the free drug concentration because NPB drugs do not or hardly bind to plasma proteins. Thus, centrifuge ultrafiltration (CF-UF) has been used in the determination of the concentration of NPB drugs in human plasma. However, with only a common centrifugation, the recovery and the reproducibility were not as excellent as expected. In addition, we discovered that the values of the volume ratio of ultrafiltrate to sample solution (Vu/Vs) were different and could not be well controlled, which may affect the determination of the drug concentration. The problem also affected the determination of other NBP drugs. In the present work, we used biapenem as a representative drug to study the effect of Vu/Vs on the analysis of NPB drugs concentration in human plasma. The results showed that a Vu/Vs value of less than 0.4 had no effect on the analysis of free drug concentration, while a Vu/Vs value of more than 0.4 was associated with increased recovery rate and overestimation of drug concentration. Therefore, to maintain a Vu/Vs value of less than 0.4 and even at a constant value is the key to accurately determine the concentration of NPB drugs in plasma. Fortunately, with an HFCF-UF device, the Vu/Vs could be well controlled and kept at 0.08 in this study. The recovery rates were almost 100% and the analysis precision was greatly improved. In pharmacokinetics studies, this method was successfully employed to determine the concentration of biapenem with excellent accuracy and reproducibility. HFCF-UF may become a feasible platform for the determination of NPB drugs.


Assuntos
Proteínas Sanguíneas/metabolismo , Preparações Farmacêuticas/metabolismo , Ultrafiltração/métodos , Cromatografia Líquida de Alta Pressão , Humanos , Limite de Detecção , Farmacocinética , Ligação Proteica , Reprodutibilidade dos Testes
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