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1.
Biomed Chromatogr ; 37(8): e5656, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37060570

RESUMO

Vancomycin (VAN) has a narrow therapeutic window and variable pharmacokinetic properties, which require timely monitoring of plasma concentration to adjust the dosage for better effectiveness. A sensitive and quantitative immunochromatographic method was developed to detect VAN in plasma. The linear response range of the method to detect plasma VAN was 1.25-50 µg/mL. The intra- and inter-assay coefficients were 4.68% and 8.81%, respectively, while the recovery was 89.10%-98.32%. The clinical comparative experiment results demonstrated a good correlation (r > 0.90) between the fluorescent immunochromatographic strip test and the mass spectrum. In this study, a simple, rapid, and high-sensitivity immunochromatographic method was established for detecting VAN, which helped establish the basis for further application of monitoring plasma concentration.


Assuntos
Vancomicina , Cromatografia de Afinidade/métodos
2.
Nano Lett ; 20(6): 4211-4219, 2020 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-32352796

RESUMO

Radiotherapy (RT) as one of the most powerful cancer treatment strategies has been greatly restricted by tumor hypoxia. A mounting effort has been devoted to develop oxygen delivery systems for boosting the RT effect. Unluckily, those systems only supplied modest oxygen, which could not afford more than once and long-time RT. Herein, we describe the development of a glucose-regulated drug release platform, allowing for a long-term tumor normoxic microenvironment and repeated RT for a long time. The repeated cycles resulted in sustained high Endostar plasma levels, which dramatically normalized the tumor vasculature and chronically reversed tumor hypoxia. Taking advantage of the inexhaustible supply of oxygen, Endo@GOx-ER enabled RT achieved an impressive cancer treatment output. To the best of our knowledge, our strategy is the initial attempt to overcome tumor-hypoxia-limited RT through the normalization of tumor vasculature by using an erythrocyte-inspired and glucose-activatable platform and it visually casts a light on the clinical development.


Assuntos
Glucose , Hipóxia , Hipóxia Tumoral , Humanos , Oxigênio , Radioterapia , Microambiente Tumoral
3.
Anal Bioanal Chem ; 412(26): 7275-7283, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32794003

RESUMO

The amounts of uric acid (UA) in non-invasive biological samples, such as saliva, are critical for diagnosis and therapy of gout, hyperuricemia, Lesch-Nyhan syndrome, and several other diseases. Here, disposable UA biosensors were fabricated with the screen printing technique on the substrate of flexible PET. The working electrode was modified with carbon nanotubes followed by uricase for UA detection with excellent selectivity. The biosensor showed good electrocatalytic activity toward UA with high sensitivity, low detection limit, and wide linear range, which covers the full range of UA levels in human saliva. We demonstrate that UA can be directly detected in human saliva with the biosensor and the experimental data were consistent with the clinical analysis. This study indicated that the non-invasive biosensor is an attractive and possible approach for the monitoring of salivary UA. Graphical abstract A disposable uric acid biosensor modified with carbon nanotubes followed by uricase was fabricated on flexible PET and applied for the monitoring of salivary uric acid in human saliva.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas/métodos , Eletrodos , Enzimas Imobilizadas , Nanotubos de Carbono/química , Saliva/química , Urato Oxidase/química , Ácido Úrico/análise , Humanos
4.
J Environ Manage ; 267: 110622, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32364132

RESUMO

This paper explores the historical relationship between weather fluctuations and mortality evolution in China. Using panel data on the annual provincial mortality rate and daily weather variables for the 1964-2008 period, we applied a dynamic model structure with sufficient controls to estimate the short-term effects of temperature shocks on China's mortality rate. Our main results show that an additional 1 °C rise in average temperature in a given year increases the annual mortality rate by an average of 3.2%. In addition, days with daily average temperatures exceeding 27 °C (30 °C) are associated with an increase in the annual mortality rate of nearly 0.1% (0.2%) or approximately 9,520 (19,040) additional deaths. In contrast, extremely cold days do not have these effects. By applying a hybrid model structure (the long difference approach) to examine the medium-term effects of temperature changes, we find that there is little evidence of overall adaptation to high temperatures when moving from the short term to the medium term. In addition, by introducing interactions between temperatures and potential modifiers such as access to doctors, hospital beds, air conditioning and refrigerators, we determined that only residential air conditioning played an important role in mitigating the temperature-mortality relationship. However, the penetration of air conditioning in China is still relatively low. These findings indicate that climate change could partially explain the historical phenomenon of China's rising mortality rate during the unprecedented economic boom experienced since the 1980s.


Assuntos
Mudança Climática , Tempo (Meteorologia) , China , Temperatura Baixa , Temperatura Alta , Mortalidade
5.
Mikrochim Acta ; 186(5): 310, 2019 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-31037355

RESUMO

The authors describe an electrochemical dopamine sensor that is based on the use of electrochemically co-reduced graphene oxide (Er-GO) and gold nanoparticles (AuNPs) on an indium-tin oxide (ITO) electrode. The synergistic effects of Er-GO and Er-AuNPs promote electron transport in the modified ITO. This results in an excellent performance for voltammetric sensing of dopamine (DA). Under the optimum conditions and a typical working potential of -0.05 V (vs. Ag/AgCl), the ITO electrode has a linear response in the 0.02-200 µM DA concentration range and a low detection limit of 15 nM. The sensor also showed a good selectivity over ascorbic acid and uric acid. The feasibility of the method was studied by analyzing DA in cerebrospinal fluid of rats. Graphical abstract Schematic presentation of one-step electrochemical co-reduction of graphene oxide (GO) and gold nanoparticles (AuNPs) on an ITO electrode for voltammetric sensing of dopamine.


Assuntos
Dopamina/análise , Eletroquímica/instrumentação , Ouro/química , Grafite/química , Nanopartículas Metálicas/química , Compostos de Estanho/química , Animais , Dopamina/líquido cefalorraquidiano , Dopamina/química , Limite de Detecção , Modelos Moleculares , Conformação Molecular , Ratos
6.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 47(1): 97-103, 2018 01 25.
Artigo em Zh | MEDLINE | ID: mdl-30146818

RESUMO

Helicobacter pylori (Hp) is widely disseminated in human, and Hp infection causes various gastrointestinal diseases, including gastric cancer. Different genotypes of Hp may cause different diseases, so the genotyping is important for clinical and basic research of Hp. This article introduces the methods for Hp genotyping, including multilocus sequence typing, pulsed-field gel electrophoresis, random amplified polymorphic DNA, amplified fragment length polymorphism, and whole-genome sequencing. By reviewing the application of these techniques in Hp genotyping and comparing their advantages and disadvantages, the article provides a theoretical basis for research into the pathogenesis, antibiotic resistance, and epidemiology of Hp infection.


Assuntos
Genótipo , Helicobacter pylori , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Infecções por Helicobacter/microbiologia , Infecções por Helicobacter/patologia , Helicobacter pylori/genética , Humanos , Reação em Cadeia da Polimerase , Pesquisa
7.
Curr Microbiol ; 74(7): 863-869, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28444418

RESUMO

This review aimed to investigate the role of Helicobacter pylori flagella on the pathogenicity of this bacterium in humans. Helicobacter pylori is a flagellated pathogen that colonizes the human gastroduodenal mucosa and produces inflammation, and is responsible for gastrointestinal disease. Its pathogenesis is attributed to colonization and virulence factors. The primary function of H. pylori flagella is to provide motility. We believe that H. pylori flagella play an important role in the colonization of the gastrointestinal mucosa. Therefore, we reviewed previous studies on flagellar morphology and motility in order to explore the relationship between H. pylori flagella and pathogenicity. Further investigation is required to confirm the association between flagella and pathogenicity in H. pylori.


Assuntos
Proteínas de Bactérias/metabolismo , Flagelos/metabolismo , Infecções por Helicobacter/microbiologia , Helicobacter pylori/metabolismo , Helicobacter pylori/patogenicidade , Animais , Proteínas de Bactérias/genética , Flagelos/genética , Mucosa Gástrica/microbiologia , Regulação Bacteriana da Expressão Gênica , Helicobacter pylori/genética , Helicobacter pylori/crescimento & desenvolvimento , Humanos
8.
Molecules ; 22(7)2017 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-28684715

RESUMO

In this study, in order to find novel biologically active penta-1,4-dien-3-one derivatives, a series of penta-1,4-dien-3-one compounds containing a substituted pyrazole subunit were designed and synthesized. Their structures were characterized by ¹H-NMR, 13C-NMR and elemental analysis. The preliminary bioassays displayed that most of the title compounds showed significant antiproliferative activity against HepG2 cell lines. Especially, compounds 7a-m, o, r, s, u, w, y and z were active against HepG2 cells with IC50 values of 0.10-5.05 µM, which were superior to that of the contrast sorafenib (IC50 = 16.20 µM).


Assuntos
Alcadienos/síntese química , Alcadienos/farmacologia , Pirazóis/química , Alcadienos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Curcumina/análogos & derivados , Curcumina/química , Desenho de Fármacos , Humanos , Nitrilas , Pirimidinas/química
9.
Molecules ; 22(6)2017 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-28587083

RESUMO

In this paper, in order to find novel biologically active pyrazole oximes, a series of pyrazole oxime compounds bearing a substituted pyridyl unit were prepared. Bioassays showed that some target compounds were found to have good acaricidal activity against Tetranychus cinnabarinus at a concentration of 500 µg/mL, compound 9q especially displayed potent acaricidal activity against T. cinnabarinus when the concentration was reduced to 100 µg/mL. Interestingly, most target compounds possessed excellent insecticidal activities against Oriental armyworm at 500 µg/mL. Moreover, some compounds were active against Aphis medicaginis and Nilaparvata lugens at 500 µg/mL. Additionally, compounds 9b, 9g, 9l, 9p, 9q, 9r, 9s, 9t, 9u, and 9v displayed significant antiproliferative activities against HepG2 cells with IC50 values of 1.53-17.27 µM, better than that of the control 5-fluorouracil (IC50 = 35.67 µM).


Assuntos
Desenho de Fármacos , Oximas/química , Oximas/farmacologia , Pirazóis/química , Pirazóis/farmacologia , Piridinas , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Inseticidas/síntese química , Inseticidas/química , Inseticidas/farmacologia , Estrutura Molecular , Oximas/síntese química , Pirazóis/síntese química , Piridinas/química , Relação Estrutura-Atividade
10.
J Surg Res ; 202(1): 216-24, 2016 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-27083969

RESUMO

BACKGROUND: Postsurgical peritoneal adhesion is a major clinical problem. Numerous anti-adhesion products have been studied, but none could be easily used to provide a physical barrier. In this study, we developed a "phase change" anti-adhesion barrier for reducing peritoneal adhesion by cross-linked copolymerization of O-carboxymethyl chitosan (CMC) and CaCl2 and addition of cyclosporin A (CsA). MATERIALS AND METHODS: The CMC-CaCl2-CsA compound was characterized by equilibrium swelling rate, weight loss, releasing effect, and coagulation test, and its biosafety was characterized by acute oral toxicity, hemolysis, and cytotoxicity. Intestinal adhesion model was applied on 64 Sprague-Dawley rats, which received CMC, CMC-CaCl2, or CMC-CaCl2-CsA treatment. At postoperative days 7 and 14, the rats were euthanized, and adhesions were graded by an investigator blinded to the treatment groups, using a predetermined adhesion scoring system. The cecum and adhesion tissue were stained with hematoxylin and eosin and antibodies for matrix metalloproteinase-9 and TIMP-1 for further histopathologic examination. RESULTS: The phase change anti-adhesive material exhibited effective blood clotting and were nontoxic in clotting experiments and acute toxicity test. The degradation rate could be adjusted using phosphate-buffered solution with varying pH. Adhesions were significantly reduced in the CMC-CaCl2-CsA treatment group compared with the control group (P < 0.001). Expression of matrix metalloproteinase-9 was stronger in CMC-CaCl2-CsA treatment group at 7 days after surgery. CONCLUSIONS: "Phase-change" adhesive can undergo changes after application, and it inhibits the formation of abdominal adhesions after surgery. The material is convenient for using by surgeons and provides an effective tool for intestinal adhesion prevention.


Assuntos
Implantes Absorvíveis , Cloreto de Cálcio/uso terapêutico , Quitosana/análogos & derivados , Ciclosporina/uso terapêutico , Doenças Peritoneais/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle , Aderências Teciduais/prevenção & controle , Animais , Materiais Biocompatíveis/uso terapêutico , Quitosana/uso terapêutico , Combinação de Medicamentos , Feminino , Imunossupressores/uso terapêutico , Intestinos/cirurgia , Masculino , Doenças Peritoneais/etiologia , Ratos , Ratos Sprague-Dawley , Método Simples-Cego , Aderências Teciduais/etiologia , Resultado do Tratamento
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