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1.
Analyst ; 145(19): 6222-6226, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-32985640

RESUMO

A sensor array mimicking a chemical nose/tongue based on bovine serum albumin nanoparticles (BSANsn) has been developed for the fluorescence pattern recognition of metal ions in biofluids. Three types of BSANsn (BSANs10, BSANs20, and BSANs40) show the same excitation/emission peak at 478/526 nm. According to the differential fluorescence variation, the sensor array shows particular fluorescence response patterns depending upon metal ions. Upon principal component analysis (PCA), it was found that the sensor array can distinguish 18 metal ions clearly at a concentration of as low as 10 µM. Moreover, different concentrations of metal ions and mixed metal ions of diverse kinds or valence states can be differentiated by the sensor in biofluids. In addition, the results were well consistent with those obtained with the traditional ICP-AES method.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Nanopartículas , Íons , Metais , Soroalbumina Bovina
2.
Biotechnol Appl Biochem ; 66(3): 426-433, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30806989

RESUMO

In this work, we present a novel facile strategy for green synthesis of polyethyleneimine (PEI)-capped carbon dots (PEI-CDs), in which citric acid and PEI were chosen as reactants and highly fluorescent PEI-CDs could be readily obtained via a simple one-pot refluxing under 120 °C within 2 H. Fluorescence studies indicate that the as-prepared PEI-CDs exhibit strong fluorescence emission at 446 nm with excitation at 365 nm. Upon the sequential addition of Cu2+ and H2 S, PEI-CDs result in an interesting "ON-OFF-ON" three-state emission responses, promising a bifunctional sensory platform. Moreover, the Cu2+ /H2 S-facilated reversible fluorescence changes of PEI-CDs have demonstrated the design of an INHIBIT logic system based on Boolean logic.


Assuntos
Carbono/química , Cobre/análise , Corantes Fluorescentes/química , Sulfeto de Hidrogênio/análise , Lógica , Polietilenoimina/química , Pontos Quânticos/química , Bioensaio/métodos , Imagem Óptica , Espectrometria de Fluorescência
3.
ACS Sens ; 4(10): 2588-2592, 2019 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-31613098

RESUMO

This letter reports on a novel cost-efficient and multifunctional barcode-like sensors array (BLSA) printed with a conductive bioinspired smart ink. The conductive  ink (P@G ink), which can be further chemically engineered with different organic ligands, was generated via facile one-pot hydrothermal reduction of graphene oxide (GO) in dopamine (DA) as coreductan Usingvarious  chemical derivatives of the P@G inks on a flexible substrate (e.g., Kapton), a highly integrated BLSA as well as smart nose/tongue mimic array were generated for simultaneous sensing and distinguishing of complex physical and chemical stimuli, including temperature, light, air pressure, relative humidity, and volatile organic compounds (VOCs). Due to these very attractive features, the reported P@G ink-based BLSA would have the potential for unique opportunities regarding "all-in-one"-yet cost-effective-disposable electronics and sensors.


Assuntos
Equipamentos e Provisões Elétricas , Tinta , Pressão do Ar , Biomimética , Dopamina , Grafite , Umidade , Luz , Temperatura , Compostos Orgânicos Voláteis
4.
Nan Fang Yi Ke Da Xue Xue Bao ; 37(11): 1545-1550, 2017 Nov 20.
Artigo em Chinês | MEDLINE | ID: mdl-29180339

RESUMO

OBJECTIVE: To observe the effects of deguelin on the proliferation of breast cancer MCF-7 cells and lung cancer H1299 cells in vitro and the expression of minichromosome maintenance protein 3 (MCM3) and CDC45 in the cells. METHODS: MTT assay was used to evaluate the proliferation of MCF-7 and H1299 cells exposed to different concentrations of deguelin for 48, 72 or 96 h. The growth of the cells was observed microscopically and the changes of MCM3 and CDC45 expressions in MCF-7 and H1299 cells following deguelin treatment were detected with fluorescence quantitative PCR. RESULTS: The proliferation of MCF-7 cells was significantly inhibited by exposure to 0.25, 0.5, 1, 5, 10, 30, and 50 µmol/L deguelin for 48, 72, and 96 h in a concentration- and time-dependent manner. In MCF-7 cells, the IC50 of deguelin at 48, 72, and 96 h was 9, 3, and 2 µmol/L, respectively. Deguelin treatments of H1299 cells at 0.5, 1, 5, 10, 30, 50, and 100 µmol/L also resulted in a concentration- and time-dependent inhibition of the cell growth with an IC50 at 96 h of 2 µmol/L. Optical microscopy of the cells revealed a decreased number of viable cells with obvious cell shrinkage following deguelin treatments. The expression of MCM3 and CDC45 were significantly reduced in the cells after deguelin treatments. CONCLUSION: Deguelin can inhibit the proliferation of MCF-7 and H1299 cells in vitro and down-regulate the expression of MCM3 and CDC45 in the cells.


Assuntos
Proliferação de Células/efeitos dos fármacos , Rotenona/análogos & derivados , Apoptose , Ciclo Celular , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7 , Componente 3 do Complexo de Manutenção de Minicromossomo , Rotenona/farmacologia
5.
World J Gastroenterol ; 9(11): 2552-6, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14606095

RESUMO

AIM: To explore the correlation of magnifying endoscopic patterns and histopathology, Helicobacter pylori (H pylori) infection of the gastric mucosa. METHODS: Gastric mucosal patterns in 140 patients with chronic gastritis were studied using Olympus GIF-Q240Z magnifying endoscope. Histopathological examination, rapid urease test and Warrthin-Starry staining were taken with biopsy samples from the magnified sites of stomach. The magnifying endoscopic patterns were compared with histopathological results and H pylori detection. RESULTS: The pit patterns of gastric mucosa were classified as types A (round spot), B (short rod), C (branched), D (reticular) and E (villus). The detection rate of chronic atrophic gastritis (CAG) by magnifying endoscopy was 94.3% (33/35), which was significantly higher than that by routine endoscopy (22.9%, 8/35) (P<0.01). The pit patterns of 31 cases of intestinal metaplasia (IM) appeared as type E in 18 cases (58.1%), type D in 8 cases (25.8%) and type C in 5 cases (16.1%). Fourteen out of 18 patients (77.8%) with complete type (type I) of IM appeared as type E of pit patterns, whereas only 4 of 13 (30.8%) patients with incomplete type (types II and III) of IM appeared as type E (P<0.05). Collecting venules in the anterior of lower part of gastric corpus were subgrouped into types R (regular), I (irregular) and D (disappeared). H pylori infection was found in 12.2%(9/74), 60%(9/15) and 84.3%(43/51) cases in these types respectively. H pylori infection rate in type R was significantly lower than that in other two types (P<0.01). CONCLUSION: Magnifying endoscopy may have an obvious value in diagnosing chronic atrophic gastritis, intestinal metaplasia and H pylori infection.


Assuntos
Endoscopia Gastrointestinal , Mucosa Gástrica/patologia , Gastrite/patologia , Infecções por Helicobacter/patologia , Helicobacter pylori , Adolescente , Adulto , Idoso , Feminino , Mucosa Gástrica/irrigação sanguínea , Humanos , Masculino , Metaplasia , Pessoa de Meia-Idade , Vênulas/patologia
6.
Acta Otolaryngol ; 129(7): 745-8, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18855163

RESUMO

CONCLUSION: The gentamicin-induced pathological alteration in the cochlear nucleus is not exclusively a secondary consequence of the damage in the cochlea. Instead, the toxic effect of gentamicin on the cochlear nucleus may occur simultaneously or even earlier than that on the cochlea. OBJECTIVES: To investigate the pathological alteration of cochlear nucleus neurons in guinea pigs following systemic application of gentamicin. MATERIALS AND METHODS: Guinea pigs were injected with gentamicin for 1 day, 3 days, 1 week, 2 weeks, and 3 weeks, respectively. In gentamicin-treated animals, the hearing function was evaluated by measuring the auditory brainstem response (ABR). The number and cross-sectional area of substance P-positive neurons in the cochlear nucleus were also measured. RESULTS: The threshold of ABR and the number of substance P-positive neurons in the cochlear nucleus were significantly increased after 1 week and 3 days of injection of gentamicin, respectively. The cross-sectional area of substance P-positive neurons in the cochlear nucleus was significantly reduced after 1-day injection of gentamicin.


Assuntos
Antibacterianos/toxicidade , Núcleo Coclear/efeitos dos fármacos , Gentamicinas/toxicidade , Animais , Limiar Auditivo/efeitos dos fármacos , Contagem de Células , Tamanho Celular/efeitos dos fármacos , Núcleo Coclear/patologia , Esquema de Medicação , Potenciais Evocados Auditivos do Tronco Encefálico/efeitos dos fármacos , Cobaias , Técnicas Imunoenzimáticas , Injeções Intraperitoneais , Neurônios/efeitos dos fármacos , Neurônios/patologia , Substância P/metabolismo
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