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1.
Nanotechnology ; 32(9): 095607, 2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33217746

RESUMO

The controllable synthesis of high-quality and large-area graphene by chemical vapor deposition (CVD) remains a challenge nowadays. The massive grain boundaries in graphene grown on polycrystalline Cu by CVD significantly reduce its carrier mobility, limiting its application in high-performance electronic devices. Here, we confirm that the synergetic pretreatment of Cu with electropolishing and surface oxidation is a more efficient way to further suppress the graphene nucleation density (GND) and to accelerate the growth rate of the graphene domain by CVD. With increasing the growth time, we found that the increasing amount of GND and growth rate of the graphene domain were both decreasing during the whole CVD process when the Cu surface was not oxidized. By contrast, they kept growing over time when the Cu surface was pre-oxidized, which suggested that the change trends of the effects on the GND and growth rate between the Cu surface morphology and oxygen were opposite in the CVD process. In addition, not only the domain shape, but the number of graphene domain layers were impacted as well, and a large number of irregular ellipse graphene wafers with dendritic multilayer emerged when the Cu surface was oxidized.

2.
Shock ; 61(6): 841-847, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691102

RESUMO

ABSTRACT: Objective: To investigate the protective effect and possible mechanisms of vitamin B 6 against renal injury in patients with sepsis. Methods: A total of 128 patients with sepsis who met the entry criteria in multiple centers were randomly divided into experimental (intravenous vitamin B 6 therapy) and control (intravenous 0.9% sodium chloride therapy) groups based on usual care. Clinical data, the inflammatory response indicators interleukin 6 (IL-6), interleukin 8 (IL-8), tumor necrosis factor (TNF-α), and endothelin-1 (ET-1), the oxidative stress response indicators superoxide dismutase, glutathione and malondialdehyde, and renal function (assessed by blood urea nitrogen, serum creatinine, and renal resistance index monitored by ultrasound) were compared between the two groups. Results: After 7 d of treatment, the IL-6, IL-8, TNF-α, and ET-1 levels in the experimental group were significantly lower than those in the control group, the oxidative stress response indicators were significantly improved in the experimental group and the blood urea nitrogen, serum creatinine, and renal resistance index values in the experimental group were significantly lower than those in the control group ( P < 0.05). There was no statistical difference between the two groups in the rate of renal replacement therapy and 28 d mortality ( P > 0.05). However, the intensive care unit length of stay and the total hospitalization expenses in the experimental group were significantly lower than those in the control group ( P < 0.05). Conclusion: The administration of vitamin B 6 in the treatment of patients with sepsis attenuates renal injury, and the mechanism may be related to pyridoxine decreasing the levels of inflammatory mediators and their regulation by redox stress.


Assuntos
Estresse Oxidativo , Sepse , Vitamina B 6 , Humanos , Sepse/tratamento farmacológico , Sepse/sangue , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Estresse Oxidativo/efeitos dos fármacos , Vitamina B 6/uso terapêutico , Endotelina-1/sangue , Fator de Necrose Tumoral alfa/sangue , Interleucina-6/sangue , Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/prevenção & controle , Interleucina-8/sangue , Superóxido Dismutase/sangue , Rim/efeitos dos fármacos , Rim/metabolismo , Nitrogênio da Ureia Sanguínea , Malondialdeído/sangue , Creatinina/sangue
3.
Front Cardiovasc Med ; 9: 821938, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35187132

RESUMO

OBJECTIVE: To evaluate the efficiency of amiodarone in preventing the occurrence of reperfusion ventricular fibrillation (RVF) after aortic cross-clamp (ACC) release in patients undergoing open-heart surgery. METHODS: We searched the Web of Science, Cochrane Library, EMBASE, and PubMed databases through January 2021 for relevant studies addressing the efficacy of amiodarone in preventing RVF after ACC release in patients undergoing cardiac surgery. A complete statistical analysis was performed using RevMan 5.3. Risk ratios (RRs) and 95% confidence intervals (CIs) were calculated to express the results of dichotomous outcomes using random or fixed-effect models. The chi-square test and I 2 test were used to calculate heterogeneity. RESULTS: Seven studies (856 enrolled patients; 311 in the amiodarone group, 268 in the lidocaine group, and 277 in the placebo group) were selected for the meta-analysis. The incidence of RVF was significantly decreased in the amiodarone group compared to the placebo group (RR = 0.69, 95%CI: 0.50-0.94, P = 0.02). However, amiodarone and lidocaine did not confer any significant difference (RR = 0.98, 95%CI: 0.61-1.59, P = 0.94). The percentage of patients requiring electric defibrillation counter shocks (DCSs) did not confer any significant difference between patients administered amiodarone and lidocaine or placebo (RR = 1.58, 95%CI: 0.29-8.74, P = 0.60; RR = 0.55, 95%CI: 0.27-1.10, P = 0.09; respectively). CONCLUSIONS: Amiodarone is more effective than a placebo in preventing RVF after ACC release in cardiac surgery. However, the amiodarone group required the same number of electrical DCSs to terminate RVF as the lidocaine or placebo groups.

4.
Artigo em Inglês | MEDLINE | ID: mdl-35394409

RESUMO

Praziquantel (PZQ) is a pyrazino-isoquinoline compound with broad spectrum of activity against parasitic trematodes and cestodes, and a key veterinary drug in the parasitic disease control field. However, PZQ residues caused by non-conforming or excessive use in food-producing animals may pose a serious threat to human health. Herein, a simple, sensitive and reproducible LC-MS/MS method was developed for the simultaneous determination of praziquantel and trans- and cis-4-hydroxypraziquantel in black goat tissues to guide the reasonable use of PZQ. The mean recoveries for three target analytes were 71.2 ∼ 117.6%, and the limits of quantification were 1.0 µg/kg. Twenty-five healthy black goats were administered a single dose of praziquantel tablets at a dose of 35 mg/kg of body weight for residue elimination study, The results revealed that praziquantel and 4-hydroxypraziquantel were rapidly depleted in goat tissues and the elimination half-lives did not exceed 1 day in all tissues except for muscle and lung. It provides guidance for the establishment of maximum residue limit of praziquantel in goat.


Assuntos
Anti-Helmínticos , Praziquantel , Animais , Anti-Helmínticos/metabolismo , Cromatografia Líquida/métodos , Cabras/metabolismo , Músculos/metabolismo , Praziquantel/química , Praziquantel/metabolismo , Espectrometria de Massas em Tandem/métodos
5.
World J Clin Cases ; 9(15): 3546-3558, 2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34046454

RESUMO

BACKGROUND: The effectiveness of adjunctive corticosteroid use in patients with coronavirus disease 2019 (COVID-19) remains inconclusive. AIM: To investigate the effectiveness of adjunctive corticosteroid therapy in patients with severe COVID-19. METHODS: We conducted a retrospective analysis of the difference in several outcomes between patients with severe COVID-19 who received corticosteroid therapy (the corticosteroid group) and patients with severe COVID-19 who did not receive corticosteroid therapy (the non-corticosteroid group). RESULTS: Seventy-five patients were included in this study. Of these, 47 patients were in the corticosteroid group and 28 patients were in the non-corticosteroid group. There were no differences between the two groups in the total length of hospital stay, the length of intensive care unit stay, high-flow oxygen days, non-invasive ventilator days, invasive ventilation days, and mortality rate. Total lesion volume ratio, consolidation volume ratio and ground-glass opacity volume ratio in the corticosteroid group decreased significantly on day 14, while those in the non-corticosteroid group did not show a significant decrease. CONCLUSION: Our results show that adjunctive corticosteroid use did not significantly improve clinical outcomes in severe COVID-19 patients, but might promote the absorption of pulmonary lesions. Larger multicenter randomized controlled studies may be needed to confirm this.

6.
J Pharm Pharmacol ; 72(11): 1645-1656, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32743812

RESUMO

OBJECTIVES: Chamomile has long been used as a medicinal plant due to its antioxidative and anti-inflammatory activity. Apigenin-7-O-glucoside (AG) is one of the major ethanol extract components from chamomile; however, the underlying mechanism remains unclear. METHODS: In this study, the antioxidant potential and the anti-inflammatory activities of AG were analysed and compared with those of trolox. We demonstrate the protective effects of AG on free radical-induced oxidative damage of DNA, proteins and erythrocytes. Flow cytometry assay was used to detect ROS production. Additionally, the expression of anti-oxidation-related and inflammation-related factors was detected by ELISA and Western blotting, respectively. KEY FINDINGS: AG and trolox showed different efficiency as antioxidant in different experimental systems. AG had similar effect as trolox to inhibit H2 O2 -induced ROS production in RAW264.7 cells, while exerted stronger inhibition against free radical-induced oxidative damage on erythrocytes than trolox. Interestingly, compared with trolox, AG also had stronger inhibitory effect on LPS-induced NF-κB/NLRP3/caspase-1 signalling in RAW246.7 cells. CONCLUSIONS: These results suggest the potential of AG as a pharmaceutical drug for anti-oxidation and anti-inflammation, and the combined usage of AG and trolox might promote its efficacy. Our findings will provide new insights into the development of new drugs with antioxidative and anti-inflammatory functions.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Apigenina/farmacologia , Cromanos/farmacologia , Mediadores da Inflamação/metabolismo , Macrófagos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Caspase 3/metabolismo , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Eritrócitos/patologia , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Células RAW 264.7 , Carneiro Doméstico , Transdução de Sinais
7.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 9): o2161, 2009 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-21577569

RESUMO

In the title compound, C(10)H(10)N(2)OS, the benzene ring is nearly co-planar with the thia-zole ring, making a dihedral angle of 2.1 (2)°. The crystal structure is stabilized by inter-molecular N-H⋯O hydrogen bonds. An intra-molecular O-H⋯N hydrogen bond is also present.

8.
Medicine (Baltimore) ; 97(17): e0524, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29703023

RESUMO

The aim of this study was to determine whether the serum level of irisin can be a candidate to predict the spinal metastasis in patients with breast cancer.In a cross-sectional study, 148 patients were recruited. Of those, 53 (35.8%) had spinal metastasis. The baseline characteristics were compared by status of spinal metastasis. Multiple logistic regression analysis was used to determine whether the serum irisin can be a candidate for predicting breast cancer to spinal metastasis. The correlation coefficient analysis was used to confirm the correlation between the serum irisin and lipid metabolic parameters and body mass index (BMI), respectively.The serum irisin was higher in patients without spinal metastasis (7.60 ±â€Š3.80). Multivariable analysis showed that the serum irisin was protective to the presence of spinal metastasis in patients with breast cancer after adjustments of age and BMI (odds ratio, 0.873; 95% confidence interval, 0.764-0.999). Furthermore, there was a positive correlation between the serum irisin and BMI (r = 0.263). The patients with metabolisc syndrome (MetS) had a higher level in serum irisin. In addition, the higher numbers of MetS components were associated with higher serum irisin.Higher serum irisin can be a protective factor of spinal metastasis in patients with breast cancer. The BMI is positively associated with the serum level of irisin. Furthermore, patients with MetS tended to have a higher level of serum irisin.


Assuntos
Neoplasias da Mama/sangue , Neoplasias da Mama/patologia , Fibronectinas/sangue , Neoplasias da Coluna Vertebral/secundário , Idoso , Biomarcadores Tumorais , Pressão Sanguínea , Índice de Massa Corporal , Neoplasias da Mama/epidemiologia , Estudos Transversais , Feminino , Humanos , Lipídeos/sangue , Modelos Logísticos , Síndrome Metabólica/epidemiologia , Pessoa de Meia-Idade , Fatores de Risco , Fatores Socioeconômicos
9.
Spine (Phila Pa 1976) ; 42(19): E1112-E1118, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28157811

RESUMO

STUDY DESIGN: Clinical case series. OBJECTIVE: The aim of this study was to explore the efficacy and safety of one-stage debridement, autogenous bone graft, and instrumentation for lumbar brucella spondylitis (LBS) via a posterior approach. SUMMARY OF BACKGROUND DATA: Reports on LBS are sporadic, and the therapeutic effect and safety of surgical interventions have not been assessed in clinical studies. METHODS: Between January 2012 and January 2014, 24 consecutive patients with symptomatic LBS who underwent a one-stage operation that combined debridement, autogenous bone graft, and instrumentation via a posterior approach were enrolled. Back pain was measured using the visual analog scale (VAS). The neurological status was evaluated with the American Spinal Injury Association (ASIA) scale. Bone healing was evaluated based on postoperative plain x-ray or computed tomography. RESULTS: All cases were followed up for an average of 14.3 + 3.5 months. The VAS scores were significantly improved at every follow-up interval. An improvement of at least one grade level was observed in the ASIA score of each patient. The average time of bone fusion was 6.8 + 1.6 months. Significant improvements of the average segmental Cobb angle was observed from a preoperative value of 18.4° + 4.6° to a last follow-up value of 21.1°â€Š±â€Š3.7°. At the last follow up, the titers of antibodies against the standard tube agglutination test, erythrocyte sedimentation rate, and C-reactive protein were negative for all patients. CONCLUSION: For LBS, systemic antibrucellosis chemotherapy is the cornerstone of treatment. When cauda equine syndrome, radiculopathy, spinal instability, and severe back pain caused by extradural nonabsorbable abscess or progressive collapse are present, surgical intervention is inevitable. One-stage debridement, autogenous bone graft, and instrumentation via a posterior approach could represent an alternative treatment for LBS, and the efficacy and safety of these techniques are satisfactory. LEVEL OF EVIDENCE: 4.


Assuntos
Transplante Ósseo/métodos , Brucella , Brucelose/cirurgia , Desbridamento/métodos , Gerenciamento Clínico , Vértebras Lombares/cirurgia , Espondilite/cirurgia , Adulto , Idoso , Brucelose/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/microbiologia , Masculino , Pessoa de Meia-Idade , Procedimentos de Cirurgia Plástica/métodos , Estudos Retrospectivos , Espondilite/diagnóstico por imagem , Espondilite/microbiologia , Resultado do Tratamento
10.
Sheng Li Xue Bao ; 54(3): 183-8, 2002 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-12075462

RESUMO

Exocytosis is a vital function of many cell types including neuron, endocrine cell and immunocyte. Secretion in immunocytes involves a complex process of signal transduction, in which many factors still remain unknown. In the last 10 years, this area has become an international hot spot of investigation, resulting in many break-through progresses. This progress was made possible by combined efforts in molecular biology, cell biology and biophysics. This review focuses on notable new knowledge and some new techniques in functional study of secretion in immunocytes.


Assuntos
Linfócitos/metabolismo , Mastócitos/metabolismo , Neutrófilos/metabolismo , Transdução de Sinais/fisiologia , Proteínas de Transporte Vesicular , Exocitose/fisiologia , Humanos , Canais Iônicos/fisiologia , Linfócitos/imunologia , Mastócitos/imunologia , Proteínas de Membrana/fisiologia , Neutrófilos/imunologia , Proteínas SNARE
11.
J Agric Food Chem ; 62(2): 516-27, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24364540

RESUMO

A new analytical strategy based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) combined with accurate mass high-resolution Orbitrap mass spectrometry (HR-Orbitrap MS) was performed for high-throughput screening, confirmation, and quantification of 22 banned or unauthorized veterinary drugs in feedstuffs according to Bulletin 235 of the Ministry of Agriculture, China. Feed samples were extracted with acidified acetonitrile, followed by cleanup using solid-phase extraction cartridge. The extracts were first screened by LC-MS/MS in a single selected reaction monitoring mode. The suspected positive samples were subjected to a specific pretreatment for confirmation and quantification of analyte of interest with LC-MS/MS and HR-Orbitrap MS. Mean recoveries for all target analytes (except for carbofuran and chlordimeform, which were about 35 and 45%, respectively) ranged from 52.2 to 90.4%, and the relative standard deviations were <15% except for 20% for carbofuran. The decision limits (CCαs) for target analytes in formulated feed were between 2.6 and 23 µg/kg, and the detection capabilities (CCßs) were between 4.2 and 34 µg/kg. The method was successfully applied to screening of real samples obtained from local feed markets and confirmation of the suspected target analytes. It provides a high-throughput, sensitive, and reliable screening, identification, and quantification of banned veterinary drugs in routine monitoring programs of feedstuffs.


Assuntos
Ração Animal/análise , Cromatografia Líquida de Alta Pressão/métodos , Contaminação de Alimentos/análise , Espectrometria de Massas/métodos , Espectrometria de Massas em Tandem/métodos , Drogas Veterinárias/análise , Animais , China , Aditivos Alimentares , Legislação de Medicamentos , Reprodutibilidade dos Testes , Extração em Fase Sólida/métodos
12.
Artigo em Inglês | MEDLINE | ID: mdl-24487039

RESUMO

A sensitive, simple and reliable multi-residue method was developed for the determination of 26 widely used veterinary antibiotics including 6 macrolides, 2 pleuromutilins, 4 tetracyclines, 2 lincosamides, 6 fluoroquinolones and 6 sulfonamides in different water matrices using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Water samples were lyophilized to dryness. Target compounds were separated on Zorbax SB-Aq column (150mm×2.1mm i.d., 3.5µm) and determined by LC-MS/MS operating in positive electrospray ionization mode. Spiked at concentration levels of 0.02, 0.4 and 4µgL(-1), recoveries of all target compounds were over 70% except sulfaquinoxaline (59.0% at 0.02µgL(-1)) with relative standard deviations below 20%. Limits of detection (LOD) and limits of quantification (LOQ) of 26 drugs ranged from 0.1 to 6.5ngL(-1) and from 0.3 to 19ngL(-1), respectively. The developed method was successfully applied to the analysis of 26 antibiotics residues in fish pond water, groundwater, biogas digester water, and lagoon wastewater samples collected from local pig farms.


Assuntos
Antibacterianos/análise , Água Doce/química , Drogas Veterinárias/análise , Águas Residuárias/química , Poluentes da Água/análise , Cromatografia Líquida/métodos , Estabilidade de Medicamentos , Liofilização/métodos , Limite de Detecção , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos
13.
Artigo em Inglês | MEDLINE | ID: mdl-23962505

RESUMO

A simple multiresidue method was developed for detecting and quantifying twenty analytes from 5 classes of prohibited veterinary drugs (ß-agonists (9), anabolic hormones (4), quinoxalines (4), tranquilizers (1), cyproheptadine, and clonidine in animal feeds using a QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) approach. Feed samples were extracted by ultrasonic-assisted extraction with a mixture of methanol-acetonitrile (50:50, v/v), followed by a cleanup using a dispersive solid-phase extraction with PSA (primary secondary amine). Target compounds were separated and determined by a liquid chromatography tandem quadrupole mass spectrometer operating in positive electrospray ionization mode, using multiple reaction monitoring (MRM). The recoveries of these compounds were between 56.7% and 103% at three spiked levels. The repeatability was lower than 10%, whereas reproducibility was no more than 15% except for nandrolone (17% at 10µgkg(-1)) and diazepam (19% at 10µgkg(-1)). Decision limits (CCαs) and detection capabilities (CCßs) ranged from 0.42 to 5.74µgkg(-1) and 5.70-9.81µgkg(-1), respectively. The method was successfully applied to screening of real samples obtained from local feed markets and confirmation of the suspected target analytes.


Assuntos
Ração Animal/análise , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Drogas Veterinárias/análise , Ração Animal/normas , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes , Drogas Veterinárias/química
14.
J Agric Food Chem ; 60(25): 6359-63, 2012 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-22670564

RESUMO

The synergistic influences of analyte concentration, sample source, and solid-phase extraction (SPE) type on matrix effects in the multiresidue analyses of eight ß-agonists with LC-ESI-MS/MS were evaluated. Porcine muscle and liver extracts and urine from diverse sources were purified by strong or mixed-mode cation exchange and molecularly imprinted polymer SPE cartridges, respectively. Three spiked concentrations (2, 10, and 20 ng/mL) of eight ß-agonists in the purified matrices and the different sample sources were analyzed. The results show that for most ß-agonists there are significant differences in matrix effects between analyte concentrations or sample sources (P < 0.05), whereas there is no significant difference in matrix effects between different SPE cartridges (P > 0.05). Results from main effects testing indicated that analyte concentration was the main effector.


Assuntos
Agonistas Adrenérgicos beta/análise , Fígado/química , Músculos/química , Extração em Fase Sólida/métodos , Urina/química , Agonistas Adrenérgicos beta/isolamento & purificação , Adsorção , Animais , Cromatografia Líquida de Alta Pressão/métodos , Polímeros/química , Extração em Fase Sólida/instrumentação , Suínos , Espectrometria de Massas em Tandem/métodos
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