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1.
Proc Natl Acad Sci U S A ; 120(40): e2311755120, 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37748078

RESUMO

Soft materials that can produce electrical energy under mechanical stimulus or deform significantly via moderate electrical fields are important for applications ranging from soft robotics to biomedical science. Piezoelectricity, the property that would ostensibly promise such a realization, is notably absent from typical soft matter. Flexoelectricity is an alternative form of electromechanical coupling that universally exists in all dielectrics and can generate electricity under nonuniform deformation such as flexure and conversely, a deformation under inhomogeneous electrical fields. The flexoelectric coupling effect is, however, rather modest for most materials and thus remains a critical bottleneck. In this work, we argue that a significant emergent flexoelectric response can be obtained by leveraging a hierarchical porous structure found in biological materials. We experimentally illustrate our thesis for a natural dry luffa vegetable-based sponge and demonstrate an extraordinarily large mass- and deformability-specific electromechanical response with the highest-density-specific equivalent piezoelectric coefficient known for any material (50 times that of polyvinylidene fluoride and more than 10 times that of lead zirconate titanate). Finally, we demonstrate the application of the fabricated natural sponge as green, biodegradable flexible smart devices in the context of sensing (e.g., for speech, touch pressure) and electrical energy harvesting.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38814604

RESUMO

Objective: To investigate the risk factors for lung infection in lung cancer patients undergoing radiotherapy. Methods: We selected 142 patients with lung cancer who underwent radiotherapy at our hospital from January 2020 to June 2021. The patients were divided into groups according to whether they had pulmonary infection during radiotherapy in our hospital, which was infected group (n=44) and the uninfected group (n=98), respectively. To observe the incidence of lung infection in lung cancer patients during radiotherapy. The distribution of pathogenic bacteria in patients with pulmonary infection was observed. Clinical data of the two groups were collected and compared. The risk factors of lung cancer patients complicated with lung infection were analyzed by binary Logistic regression. Results: All patients with lung cancer complicated with lung infection underwent relevant examination, and the results showed that they were all complicated infections, and the composition ratio of Klebsiella pneumoniae was the highest (31.82%), followed by Staphylococcus, Pseudomonas, and fungi, which accounted for 27.27%, 22.73%, and 18.18%, respectively. Binary Logistic regression analysis showed that age ≥60 years old, smoking history ≥30 years, radiotherapy duration of combined drug regimen > 2 weeks, pathogenic bacteria combined infection, albumin content < 30 g/L were risk factors for lung cancer patients during radiotherapy. Conclusion: Age ≥60 years old, smoking history ≥30 years old, radiotherapy duration of combined drug regimen > 2 weeks, pathogenic bacteria combined infection, albumin content < 30 g/L are the risk factors for lung cancer patients during radiotherapy. Clinical prevention and intervention should be based on the aforementioned independent risk factors to decrease the incidence of lung infections, thereby enhancing patient prognosis.

3.
J Asian Nat Prod Res ; : 1-21, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39132822

RESUMO

This study aims to explore the mechanisms of the inhibitory effect of kaempferol on the invasion and metastasis of gastric cancer (GC) cells through network pharmacology prediction and experimental verification. It identifies core targets via PPI network analysis and finds that kaempferol binds to these targets well. In vitro experiments showed that kaempferol could inhibit the proliferation, colony formation, migration and invasion of GC cells. Western blotting indicated kaempferol may reduce AKT and GSK3ß phosphorylation, leading to lower expression of invasion-related genes SRC, MMP9, CXCR4, KDR, and MMP2. Overall, kaempferol may prevent migration and invasion of GC cells via the AKT/GSK3ß signaling pathway.

4.
Phys Chem Chem Phys ; 25(18): 12565-12586, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37102210

RESUMO

Catalyst activity affects the reaction rate, and an increasing number of studies have shown that strain can significantly increase the electrocatalytic activity. Catalysts such as alloys and core-shell structures can modulate their properties through strain effects. Reasonable simulation techniques can be used to predict and design the catalytic performance based on understanding the strain action mechanism. Therefore, the methodological flow of theoretical simulations is summarised in this review. The mechanism underlying the strain-adsorption-reaction relationship is discussed using density functional theory (DFT) calculations. An introduction to DFT is given first, followed by a quick rundown of the strain classification and application. Typical electrocatalytic reactions, namely, the hydrogen and oxygen evolution reactions and oxygen reduction reaction, are taken as examples. After briefly explaining these reactions, the relevant studies on simulating the strain to tune the catalyst performance are covered. The simulation methods are summarised and analysed to observe the effects of strain on electrocatalytic properties. Finally, a summary of the issues with simulated strain-assisted design and a discussion on the perspectives and forecasts for the future design of effective catalysts are provided.

5.
Nutr Cancer ; 74(10): 3574-3581, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35762207

RESUMO

Postoperative complications of gastrectomy for gastric cancer affect the efficacy of surgery. It is of clinical significance to identify high-risk patients with postoperative complications as early as possible. A total of 206 patients who underwent gastrectomy were enrolled in this study. Univariate and multivariate analyses were used to determine the risk factors for postoperative complications. The cutoff value and diagnostic accuracy of the C-reactive protein/albumin ratio were calculated by receiver operating characteristic curves. A total of 64 (31.1%) patients developed postoperative complications. Multivariate analysis confirmed that the C-reactive protein/albumin ratio on the first day after operation was an independent risk factor for postoperative complications (OR = 2.538, 95%CI: 1.346-4.785, P = 0.004). The cutoff value of the C-reactive protein/albumin ratio on the first day after operation was 2.105 calculated by receiver operating characteristic curves. Patients with a C-reactive protein/albumin ratio greater than 2.105 had a higher incidence of postoperative complications (43.2% vs 22.0%, P = 0.001) and longer postoperative hospital stay (15.3 ± 1.2 vs 13.0 ± 0.5, P = 0.042) than patients with less than 2.105. Patients with C-reactive protein/albumin ratio greater than 2.105 on the first day after operation are more likely to have postoperative complications.


Assuntos
Neoplasias Gástricas , Albuminas , Proteína C-Reativa/análise , Gastrectomia/efeitos adversos , Humanos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Neoplasias Gástricas/etiologia
6.
BMC Surg ; 21(1): 309, 2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34253214

RESUMO

BACKGROUND: Small bowel obstruction (SBO) is common and usually requires surgical intervention. Intestinal plication is a traditional but critical strategy for SBO in certain scenarios. This study is to compare the short-term and long-term outcome between internal and external plications in the management of SBO. METHODS: All patients receiving intestinal plication in our hospital were retrospectively collected. Short-term outcome including postoperative complications, reoperation, postoperative ICU stay, starting day of liquid diet and postoperative hospitalization, as well as long-term outcome including recurrence of obstruction, readmission, reoperation and death were compared between groups. Gut function at annual follow-up visits was evaluated as well. RESULTS: Nine internal and 11 external candidates were recruited into each group. The major causes of plication were adhesive obstruction, abdominal cocoon, volvulus and intussusception. Lower incidence of postoperative complication (p = 0.043) and shorter postoperative hospitalization (p = 0.049) was observed in internal group. One patient receiving external plication died from anastomosis leakage. During the 5-year follow-up period, the readmission rate was low in both groups (22.2 % vs. 9.1 %), and none of patients required reoperation or deceased. None of patients exhibited gut dysfunction, and all patients restored normal gut function after 4 years. Patients in external group demonstrated accelerated recovery of gut function after surgery. CONCLUSIONS: This study compares short-term and long-term outcome of patients receiving internal or external intestinal plication. We suggest a conservative attitude toward external plication strategy. Surgical indication for intestinal plication is critical and awaits future investigations.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório , Obstrução Intestinal , Humanos , Obstrução Intestinal/etiologia , Obstrução Intestinal/cirurgia , Intestino Delgado/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/cirurgia , Reoperação , Estudos Retrospectivos
7.
BMC Surg ; 21(1): 174, 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33789664

RESUMO

BACKGROUND: Lymph node metastasis (LNM) plays a vital role in the determination of clinical outcomes in patients with gastric neuroendocrine tumor (G-NET). Preoperative identification of LNM is helpful for intraoperative lymphadenectomy. This study aims to investigate risk factors for LNM in patients with G-NET. METHODS: We performed a retrospective study involving 37 patients in non-LNM group and 82 patients in LNM group. Data of demographics, preoperative lab results, clinical-pathological results, surgical management, and postoperative situation were compared between groups. Significant parameters were subsequently entered into logistic regression for further analysis. RESULTS: Patients in LNM group exhibited older age (p = 0.011), lower preoperative albumin (ALB) (p = 0.003), higher carcinoembryonic antigen (CEA) (p = 0.020), higher International normalized ratio (p = 0.034), longer thrombin time (p = 0.018), different tumor location (p = 0.005), higher chromogranin A positive rate (p = 0.045), and higher Ki-67 expression level (p = 0.002). Logistic regression revealed ALB (p = 0.043), CEA (p = 0.032), tumor location (p = 0.013) and Ki-67 (p = 0.041) were independent risk factors for LNM in G-NET patients. CONCLUSIONS: ALB, CEA, tumor location, and Ki-67 expression level correlate with the risk of LNM in patients with G-NET.


Assuntos
Metástase Linfática , Tumores Neuroendócrinos , Neoplasias Gástricas , Idoso , Humanos , Tumores Neuroendócrinos/patologia , Tumores Neuroendócrinos/cirurgia , Estudos Retrospectivos , Fatores de Risco , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia
8.
Psychol Health Med ; 26(5): 533-542, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32290683

RESUMO

This paper aimed to explore the characteristics of the top-100 cited articles on the biomarkers in the depression field and strive to find the future trend. The top-100 cited articles were selected from the Web of Science Core Collection database. Excel 2016 and VOSviewer 1.6.9 were used to analyze the information. Forty-six journals contributed to these 100 articles, and Biological Psychiatry published the largest number of articles (n = 18). Holsboer F (n = 4) contributed the most, and Maes M (n = 118) was the most co-cited author. Twenty-six countries and 220 organizations contributed to the top-100 articles, respectively. The USA (n = 48) was the main contributor. NIMH and Kings Coll London both participated in seven articles. Major depression (n = 62), depression (n = 38) and biomarker (n = 31) were the top three keywords. These results indicated that articles published in journals with higher impact factors are more likely to spread. Compared with developing countries, developed countries have contributed more to these articles. It is suggested that cooperation should be strengthened between developed countries and developing counties in the future. More research on biomarkers in the depression field may still mainly focus on major depression.Abbreviation: WoS = Web of Science; JCR = Journal Citation Reports; UK = United Kingdom; NIMH = The National Institute of Mental Health; UCL = University College London; IF = Impact factor; BDNF = brain-derived neurotrophic factor; USA = United States.


Assuntos
Bibliometria , Biomarcadores , Depressão , Humanos , Londres , Reino Unido , Estados Unidos
9.
Langmuir ; 35(21): 6916-6921, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31058512

RESUMO

The dynamics of evaporating water droplets on heated graphene-poly(dimethylsiloxane) (PDMS) composites is investigated experimentally and theoretically. By inserting graphene nucleates in PDMS, we report the effect of change in thermal resistance on the evaporation process of water droplets on the heated graphene-PDMS composite surface. By dispersing graphene within the PDMS matrix, the evaporation of water droplets is enhanced. The graphene nucleate density over the surface was controlled by varying graphene wt % from 0 to 2%, which in turn controls the thermal resistance and hence the evaporation rate. Experimentally, the maximum evaporation rate of 0.0044 µL/s was observed for the sample of 2 wt % graphene-PDMS composite. The evaporation rate on a 2 wt % graphene-PDMS composite surface is about 1.5 times higher compared to that of plain PDMS without graphene. A theoretical model confirms that the initial contact angle and the presence of thermal coupling between liquid droplets and the substrate play an important role in evaporation dynamics. Thermal conductance increases 3 times with the increase in graphene wt % from 0.1 to 2.0 wt % in PDMS. The heat-storing capacity of graphene is responsible for the enhanced evaporation. The experimental findings are in good agreement with theoretical results. These samples were found insensitive to degradation and may find potential applications where high efficiency and high heat flux are needed.

10.
Bioorg Med Chem Lett ; 29(23): 126723, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31624042

RESUMO

Six novel target compounds 5-(4-hydroxyphenyl)-3H-1,2-dithiole-3-thione (ADT) based fibrates were synthesized and evaluated. All the synthesized compounds were preliminarily screened by using the Triton WR-1339-induecd hyperlipidemia model, in which T1 exhibited more potent hypolipidemic property than positive drug fenofibrate (FF). T1 also significantly decreased serum triglycerides (TG), total cholesterol (TC) and low density lipoprotein cholesterin (LDL) in methionine solution (Mets) induced hyperlipidemic mice. Moreover, hepatic transaminases (AST and ALT) were obviously ameliorated after treatment with T1 and the histological observation indicated that T1 ameliorated the injury in liver tissue and inhibited the hepatic lipid accumulation. In the livers of T1-administrated rat, the levels of PPARα related to lipids metabolism were up-regulated. Additional effects such as antioxidant, anti-inflammatory and H2S releasing action confirmed and reinforced the activity of T1 as a potential multifunctional hypolipidemic and hepatoprotective agent.


Assuntos
Ácidos Fíbricos/síntese química , Hipolipemiantes/uso terapêutico , Metabolismo dos Lipídeos/efeitos dos fármacos , Animais , Ácidos Fíbricos/química , Hipolipemiantes/farmacologia , Masculino , Camundongos , Ratos
11.
Bioorg Chem ; 89: 103000, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31132604

RESUMO

Both nitric oxide (NO) dysfunction and oxidative stress have been regarded as the important factors in the development and progression of diabetes and its complications. Multifunctional compounds with hypoglycemic, NO supplementation and anti-oxidation will be the promising agents for treatment of diabetes. In this study, six phenylfuroxan nitric oxide (NO) donor phenols were synthesized, which were designed via a combination approach with phenylfuroxan NO-donor and natural phenols. These novel synthetic compounds were screened in vitro for α-glucosidase inhibition, NO releasing, anti-oxidation, anti-glycation and anti-platelet aggregation activity as well as vasodilatation effects. The results exhibited that compound T5 displayed more excellent activity than other compounds. Moreover, T5 demonstrated significant hypoglycemic activity in diabetic mice and oral glucose tolerance test (OGTT) mice. T5 also showed NO releasing and anti-oxidation in diabetic mice. Based on these results, compound T5 deserves further study as potential new multifunctional anti-diabetic agent with antioxidant, NO releasing, anti-platelet aggregation and vasodilatation properties.


Assuntos
Antioxidantes/farmacologia , Inibidores de Glicosídeo Hidrolases/farmacologia , Hipoglicemiantes/farmacologia , Doadores de Óxido Nítrico/farmacologia , Fenóis/farmacologia , Inibidores da Agregação Plaquetária/farmacologia , Animais , Antioxidantes/síntese química , Antioxidantes/química , Compostos de Bifenilo/antagonistas & inibidores , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Relação Dose-Resposta a Droga , Desenho de Fármacos , Inibidores de Glicosídeo Hidrolases/síntese química , Inibidores de Glicosídeo Hidrolases/química , Hipoglicemiantes/síntese química , Hipoglicemiantes/química , Masculino , Camundongos , Camundongos Endogâmicos ICR , Estrutura Molecular , Doadores de Óxido Nítrico/síntese química , Doadores de Óxido Nítrico/química , Fenóis/síntese química , Fenóis/química , Picratos/antagonistas & inibidores , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/síntese química , Inibidores da Agregação Plaquetária/química , Estreptozocina , Relação Estrutura-Atividade , alfa-Glucosidases/metabolismo
12.
Bioorg Med Chem Lett ; 28(23-24): 3787-3792, 2018 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-30337230

RESUMO

Hypolipidemic effects of the newly synthesized 5-(4-hydroxyphenyl)-3H-1,2-dithiole-3-thione-based fibrates were evaluated in Triton WR-1339 and high-fat diet (HFD)-induced hyperlipidemic mice. Preliminary screening of all the synthesized compounds was done by using an acute model (Triton WR-1339 model), in which compound 6 shown more significant antidyslipidemic activity than fenofibrate (FF). The compound 6 was also found to reduce serum triglyceride (TG), total cholesterol (TC) and low density lipoprotein cholesterin (LDL) in HFD-induced hyperlipidemic mice. Moreover, compound 6 displayed hepatoprotective effect, a significant amelioration in hepatic indices (AST and ALT) toxicity was observed and the histological examination showed that compound 6 inhibited the development of hepatic lipid accumulation and ameliorated the damage in hepatic tissue compared to model mice. Additional effects such as the potent antioxidant and anti-inflammatory action confirmed and reinforced the efficacy of compound 6 as a new agent of dual-effect hypolipidemic and hepatoprotective activities.


Assuntos
Ácidos Fíbricos/química , Ácidos Fíbricos/uso terapêutico , Hiperlipidemias/tratamento farmacológico , Hipolipemiantes/química , Hipolipemiantes/uso terapêutico , Tionas/química , Tionas/uso terapêutico , Tiofenos/química , Tiofenos/uso terapêutico , Animais , Dieta Hiperlipídica/efeitos adversos , Ácidos Fíbricos/farmacologia , Hiperlipidemias/sangue , Hiperlipidemias/etiologia , Hiperlipidemias/metabolismo , Hipolipemiantes/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Substâncias Protetoras/química , Substâncias Protetoras/farmacologia , Substâncias Protetoras/uso terapêutico , Tionas/farmacologia , Tiofenos/farmacologia
13.
Bioorg Med Chem Lett ; 28(23-24): 3731-3735, 2018 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-30343953

RESUMO

Nitric oxide (NO) dysfunction has been found to be an important factor in both the development and progression of diabetic complications due to its many roles in the vascular system. Multifunctional compounds with hypoglycemic and endothelial protective action will be promising agents for the treatment of diabetes and its complications. In this study, a series of novel NO-donating sitagliptin derivatives and relevant metabolites were synthesized and evaluated as potential multifunctional hypoglycemic agents. All of synthetic compounds shown remarkable inhibitory activity against dipeptidyl peptidase IV (DPP-IV) in vitro and demonstrated excellent hypoglycemic activities in diabetic mice, similar to the activity of sitagliptin, and compounds T1-T4 shown different extents of NO-releasing abilities and potent antioxidant abilities in vivo. By screening in DPP-4, compound T4 was recognized as a potent DPP-4 inhibitor with the IC50 value of 0.060 µM. Docking study revealed compound T4 has a favorable binding mode. Furthermore, compounds T1-T4 exhibited different extents of NO-releasing abilities and excellent anti-platelet aggregation in vitro. The overall results suggested that T4 could help to the amelioration of endothelial dysfunction by reducing blood glucose, lessening oxidative stress and raising NO levels as well as inhibiting platelet aggregation. Based on this research, compound T4 deserves further investigation as potential new multifunctional anti-diabetic agent with antioxidant, anti-platelet aggregation and endothelial protective properties.


Assuntos
Inibidores da Dipeptidil Peptidase IV/química , Hipoglicemiantes/química , Doadores de Óxido Nítrico/química , Inibidores da Agregação Plaquetária/química , Fosfato de Sitagliptina/análogos & derivados , Animais , Glicemia/análise , Glicemia/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Inibidores da Dipeptidil Peptidase IV/síntese química , Inibidores da Dipeptidil Peptidase IV/farmacologia , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Humanos , Hipoglicemiantes/síntese química , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Camundongos Endogâmicos ICR , Simulação de Acoplamento Molecular , Óxido Nítrico/metabolismo , Doadores de Óxido Nítrico/síntese química , Doadores de Óxido Nítrico/farmacologia , Doadores de Óxido Nítrico/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/síntese química , Inibidores da Agregação Plaquetária/farmacologia , Inibidores da Agregação Plaquetária/uso terapêutico , Fosfato de Sitagliptina/síntese química , Fosfato de Sitagliptina/farmacologia , Fosfato de Sitagliptina/uso terapêutico
14.
Bioorg Med Chem Lett ; 28(18): 3119-3122, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30119959

RESUMO

Oxidative stress has been regarded as the leading mechanism of the hepatotoxicity of clofibrate (CF). To achieve multifunctional novel hypolipidemic agents with hypolipidemia, antioxidant, and ameliorating liver injury, clofibric acid derivative hydroxytyrosol-clofibrate (CF-HT) was synthesized by molecular hybridization. CF-HT exhibited significant hypolipidemia, reducing serum triglyceride (TG), total cholesterol (TC), and malonaldehyde (MDA) by 30%, 33%, and 29% in hyperlipidemic mice induced by Triton WR 1339. CF-HT also shown hepatoprotective effect, a significant decrease in hepatic indices toxicity was observed, i.e. aspartate and lactate transaminases (AST and ALT) activities, alkalines phosphatases (ALP), and total bilirubin (TBIL) levels. The liver weight and liver coefficient were also ameliorated. Serum superoxide dismutase (SOD) was significantly elevated, and serum catalase (CAT) and malondialdehyde (MDA) content were remarkably restored. The hepatic glutathione (GSH) content was obviously increased and hepatic oxidized glutathione (GSSG) content was reduced dramatically by CF-HT, as compared to the CF treated mice (p < 0.05). Moreover, the histopathological damage that hepatocyte hyperplasia and hypertrophy was also significantly ameliorated by treatment with CF-HT. Therefore, the results indicated that CF-HT exerted more potent hypolipidemic activity and definite hepatoprotective effect which may mainly be associated with its antioxidative property in mice.


Assuntos
Antioxidantes/farmacologia , Clofibrato/farmacologia , Hepatócitos/efeitos dos fármacos , Hipolipemiantes/farmacologia , Álcool Feniletílico/análogos & derivados , Animais , Antioxidantes/administração & dosagem , Antioxidantes/química , Peso Corporal/efeitos dos fármacos , Clofibrato/administração & dosagem , Clofibrato/química , Relação Dose-Resposta a Droga , Hepatócitos/metabolismo , Hipolipemiantes/administração & dosagem , Hipolipemiantes/química , Masculino , Camundongos , Camundongos Endogâmicos ICR , Estrutura Molecular , Tamanho do Órgão/efeitos dos fármacos , Álcool Feniletílico/administração & dosagem , Álcool Feniletílico/química , Álcool Feniletílico/farmacologia , Polietilenoglicóis/farmacologia , Relação Estrutura-Atividade
16.
J Sci Food Agric ; 97(6): 1805-1810, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27476832

RESUMO

BACKGROUND: Mycotoxins, which may contaminate peanut and peanut products, are responsible for many diseases to humans. Aflatoxin B1 (AFB1), aflatoxin G1 (AFG1), aflatoxin B2 (AFB2), aflatoxin G2 (AFG2), ochratoxin A (OTA) and zearalenone (ZEN) are considered the most relevant groups of mycotoxins found in food. This work aimed to develop a high-performance liquid chromatography method with a fluorescence detector (HPLC-FLD) combined with dispersive liquid-liquid microextraction (DLLME) method for the simultaneous determination of the six mycotoxins in peanuts. The six mycotoxins were simultaneously determined under their best wavelength by means of changing wavelength. RESULTS: Under the optimum conditions, the linear ranges were 1-100 ng mL-1 for AFB1, AFG1 and OTA, 0.3-30 ng mL-1 for AFB2 and AFG2, 5-1000 ng mL-1 for ZEN, with the correlation coefficient (R2 ) of 0.9969-0.9997. Limits of detection (LODs) were 0.10, 0.10, 0.30, 0.03, 0.03 and 1.0 µg kg-1 , respectively, and the mean recoveries were in the range of 83.1% to 99.3% with RSD < 10% (n = 6, independent analysis). Thirteen (46%) of these tested samples were contaminated with at least one mycotoxin. CONCLUSION: The proposed method was demonstrated to be simple, highly selective, accurate, reliable, and was successfully applied to simultaneously analyse the six mycotoxins in real peanut samples from China. © 2016 Society of Chemical Industry.


Assuntos
Arachis/química , Cromatografia Líquida de Alta Pressão/métodos , Contaminação de Alimentos/análise , Micotoxinas/química , China , Cromatografia Líquida de Alta Pressão/instrumentação , Fluorescência , Limite de Detecção
17.
Ann Clin Microbiol Antimicrob ; 14: 17, 2015 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-25857356

RESUMO

BACKGROUND: Early diagnosis and appropriate antibiotic treatment can significantly reduce mortality of nosocomial bacterial meningitis. However, it is a challenge for clinicians to make an accurate and rapid diagnosis of bacterial meningitis. This study aimed at determining whether combined biomarkers can provide a useful tool for the diagnosis of bacterial meningitis. METHODS: A retrospective study was carried out. Cerebrospinal fluid (CSF) levels of decoy receptor 3 (DcR3) and soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) were detected by enzyme-linked immunosorbent assay (ELISA). RESULTS: The patients with bacterial meningitis had significantly elevated levels of the above mentioned biomarkers. The two biomarkers were all risk factors with bacterial meningitis. The biomarkers were constructed into a "bioscore". The discriminative performance of the bioscore was better than that of each biomarker, with an area under the receiver operating characteristic (ROC) curve (AUC) of 0.842 (95% confidence intervals (CI) 0.770-0.914; p< 0.001). CONCLUSIONS: Combined measurement of CSF DcR3 and sTREM-1 concentrations improved the prediction of nosocomial bacterial meningitis. The combined strategy is of interest and the validation of that improvement needs further studies.


Assuntos
Infecção Hospitalar/diagnóstico , Glicoproteínas de Membrana/líquido cefalorraquidiano , Meningites Bacterianas/diagnóstico , Células Mieloides/metabolismo , Membro 6b de Receptores do Fator de Necrose Tumoral/líquido cefalorraquidiano , Adulto , Biomarcadores/líquido cefalorraquidiano , Infecção Hospitalar/líquido cefalorraquidiano , Feminino , Humanos , Meningites Bacterianas/líquido cefalorraquidiano , Pessoa de Meia-Idade , Curva ROC , Receptores Imunológicos , Estudos Retrospectivos , Receptor Gatilho 1 Expresso em Células Mieloides , Adulto Jovem
18.
J Sep Sci ; 38(12): 2126-31, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25845463

RESUMO

A novel method has been developed for the analysis of zearalenone in maize products by vortex-assisted ionic-liquid-based dispersive liquid-liquid microextraction combined with HPLC and fluorescence detection. Maize samples were extracted with methanol/water (80:20, v/v) and the extraction solution was then used as the dispersive solvent in the microextraction procedure. The analyte was rapidly transmitted to a small volume of ionic liquid and was determined by HPLC. Various parameters affecting the recovery of the mycotoxin were investigated, such as the type and volume of the extraction solvent, the type and volume of the dispersive solvent, the pH of the aqueous phase, the salt addition, and the time of vortex and centrifugation. Under the optimal experimental conditions, a good linearity of the analyte was obtained in the range of 1.0-1000.0 µg/L with the correlation coefficient of 0.9998. The limit of detection (S/N = 3) and quantification (S/N = 10) were 0.3 and 1.0 µg/kg, and the mean recoveries ranged from 83.5 to 94.9%, with a relative standard deviation less than 5.0%. The proposed method was demonstrated to be simple, cheap, quick, and highly selective and was successfully applied to the determination of zearalenone in maize products.

19.
Biomed Chromatogr ; 28(4): 459-62, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24132719

RESUMO

A simple, rapid and accurate high-performance liquid chromatography method with ultraviolet-visible detection was developed for the determination of five amino acid neurotransmitters - aspartate, glutamic acid, glycine, taurine and γ-aminobutyric acid - in rat hippocampi with pre-column derivatization with 4-fluoro-7-nitrobenzofurazan. Several conditions which influenced derivatization and separation, such as pH, temperature, acetonitrile percentage mobile phase and flow rate, were optimized to obtain a suitable protocol for amino acids quantification in samples. The separation of the five neurotransmitter derivatives was performed on a C18 column using a mobile phase consisting of phosphate buffer (0.02 mol/L, pH 6.0)-acetonitrile (84:16, v/v) at a flow rate of 1.0 mL/min with the column temperature at 30°C. The detection wavelength was 472 nm. Without gradient elution, the five neurotransmitter derivatives were completely separated within 15 min. The linear relation was good in the range from 0.50 to 500 µmol/L, and the correlation coefficients were ≥0.999. Intra-day precision was between 1.8 and 3.2%, and inter-day precision was between 2.4 and 4.7%. The limits of detection (signal-to-noise ratio 3) were from 0.02 to 0.15 µmol/L. The established method was used to determine amino acid neurotransmitters in rat hippocampi with satisfactory recoveries varying from 94.9 to 105.2%.


Assuntos
4-Cloro-7-nitrobenzofurazano/análogos & derivados , Aminoácidos/análise , Cromatografia Líquida de Alta Pressão/métodos , Hipocampo/química , Neurotransmissores/análise , 4-Cloro-7-nitrobenzofurazano/química , Animais , Estabilidade de Medicamentos , Corantes Fluorescentes/química , Limite de Detecção , Modelos Lineares , Masculino , Ratos , Ratos Wistar , Reprodutibilidade dos Testes
20.
Int J Mol Sci ; 15(11): 19962-70, 2014 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-25372942

RESUMO

Nosocomial bacterial meningitis requires timely treatment, but what is difficult is the prompt and accurate diagnosis of this disease. The aim of this study was to assess the potential role of decoy receptor 3 (DcR3) levels in the differentiation of bacterial meningitis from non-bacterial meningitis. A total of 123 patients were recruited in this study, among them 80 patients being with bacterial meningitis and 43 patients with non-bacterial meningitis. Bacterial meningitis was confirmed by bacterial culture of cerebrospinal fluid (CSF) culture and enzyme-linked immunosorbent assay (ELISA) was used to detect the level of DcR3 in CSF. CSF levels of DcR3 were statistically significant between patients with bacterial meningitis and those with non-bacterial meningitis (p<0.001). A total of 48.75% of patients with bacterial meningitis received antibiotic>24 h before CSF sampling, which was much higher than that of non-bacterial meningitis. CSF leucocyte count yielded the highest diagnostic value, with an area under the receiver operating characteristic curve (ROC) of 0.928, followed by DcR3. At a critical value of 0.201 ng/mL for DcR3, the sensitivity and specificity were 78.75% and 81.40% respectively. DcR3 in CSF may be a valuable predictor for differentiating patients with bacterial meningitis from those with non-bacterial meningitis. Further studies are needed for the validation of this study.


Assuntos
Meningites Bacterianas/diagnóstico , Membro 6b de Receptores do Fator de Necrose Tumoral/líquido cefalorraquidiano , Adulto , Fatores Etários , Área Sob a Curva , Diagnóstico Diferencial , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Curva ROC
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