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1.
Opt Express ; 32(11): 20024-20034, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38859121

RESUMO

An optical fiber sensing probe using a composite sensitive film of polyacrylonitrile (PAN) nanofiber membrane and gold nanomembrane is presented for the detection of a carcinoembryonic antigen (CEA), a biomarker associated with colorectal cancer and other diseases. The probe is based on a tilted fiber Bragg grating (TFBG) with a surface plasmon resonance (SPR) gold nanomembrane and a functionalized polyacrylonitrile (PAN) PAN nanofiber coating that selectively binds to CEA molecules. The performance of the probe is evaluated by measuring the spectral shift of the TFBG resonances as a function of CEA concentration in buffer. The probe exhibits a sensitivity of 0.46 dB/(µg/ml), a low limit of detection of 505.4 ng/mL in buffer, and a good selectivity and reproducibility. The proposed probe offers a simple, cost-effective, and a novel method for CEA detection that can be potentially applied for clinical diagnosis and monitoring of CEA-related diseases.


Assuntos
Resinas Acrílicas , Antígeno Carcinoembrionário , Ouro , Nanofibras , Fibras Ópticas , Ressonância de Plasmônio de Superfície , Antígeno Carcinoembrionário/análise , Ouro/química , Nanofibras/química , Ressonância de Plasmônio de Superfície/instrumentação , Ressonância de Plasmônio de Superfície/métodos , Resinas Acrílicas/química , Humanos , Técnicas Biossensoriais/instrumentação , Membranas Artificiais , Nanopartículas Metálicas/química , Reprodutibilidade dos Testes , Tecnologia de Fibra Óptica/instrumentação
2.
Int J Mol Sci ; 22(15)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34360998

RESUMO

Candida albicans, an opportunistic fungus, causes dental caries and contributes to mucosal bacterial dysbiosis leading to a second infection. Furthermore, C.albicans forms biofilms that are resistant to medicinal treatment. To make matters worse, antifungal resistance has spread (albeit slowly) in this species. Thus, it has been imperative to develop novel, antifungal drug compounds. Herein, a peptide was engineered with the sequence of RRFSFWFSFRR-NH2; this was named P19. This novel peptide has been observed to exert disruptive effects on fungal cell membrane physiology. Our results showed that P19 displayed high binding affinity to lipopolysaccharides (LPS), lipoteichoic acids (LTA) and the plasma membrane phosphatidylinositol (PI), phosphatidylserine (PS), cardiolipin, and phosphatidylglycerol (PG), further indicating that the molecular mechanism of P19 was not associated with the receptor recognition, but rather related to competitive interaction with the plasma membrane. In addition, compared with fluconazole and amphotericin B, P19 has been shown to have a lower potential for resistance selection than established antifungal agents.


Assuntos
Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Oligopeptídeos/farmacologia , Antifúngicos/química , Candida albicans/fisiologia , Cardiolipinas/metabolismo , Membrana Celular/efeitos dos fármacos , Lipopolissacarídeos/metabolismo , Oligopeptídeos/química , Fosfatidilgliceróis/metabolismo , Fosfatidilinositóis/metabolismo , Fosfatidilserinas/metabolismo , Ácidos Teicoicos/metabolismo , Triptofano/química
3.
BMJ ; 381: e071609, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-37019448

RESUMO

OBJECTIVE: To evaluate the quality of evidence, potential biases, and validity of all available studies on dietary sugar consumption and health outcomes. DESIGN: Umbrella review of existing meta-analyses. DATA SOURCES: PubMed, Embase, Web of Science, Cochrane Database of Systematic Reviews, and hand searching of reference lists. INCLUSION CRITERIA: Systematic reviews and meta-analyses of randomised controlled trials, cohort studies, case-control studies, or cross sectional studies that evaluated the effect of dietary sugar consumption on any health outcomes in humans free from acute or chronic diseases. RESULTS: The search identified 73 meta-analyses and 83 health outcomes from 8601 unique articles, including 74 unique outcomes in meta-analyses of observational studies and nine unique outcomes in meta-analyses of randomised controlled trials. Significant harmful associations between dietary sugar consumption and 18 endocrine/metabolic outcomes, 10 cardiovascular outcomes, seven cancer outcomes, and 10 other outcomes (neuropsychiatric, dental, hepatic, osteal, and allergic) were detected. Moderate quality evidence suggested that the highest versus lowest dietary sugar consumption was associated with increased body weight (sugar sweetened beverages) (class IV evidence) and ectopic fatty accumulation (added sugars) (class IV evidence). Low quality evidence indicated that each serving/week increment of sugar sweetened beverage consumption was associated with a 4% higher risk of gout (class III evidence) and each 250 mL/day increment of sugar sweetened beverage consumption was associated with a 17% and 4% higher risk of coronary heart disease (class II evidence) and all cause mortality (class III evidence), respectively. In addition, low quality evidence suggested that every 25 g/day increment of fructose consumption was associated with a 22% higher risk of pancreatic cancer (class III evidence). CONCLUSIONS: High dietary sugar consumption is generally more harmful than beneficial for health, especially in cardiometabolic disease. Reducing the consumption of free sugars or added sugars to below 25 g/day (approximately 6 teaspoons/day) and limiting the consumption of sugar sweetened beverages to less than one serving/week (approximately 200-355 mL/week) are recommended to reduce the adverse effect of sugars on health. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42022300982.


Assuntos
Açúcares da Dieta , Aumento de Peso , Humanos , Açúcares da Dieta/efeitos adversos , Estudos Transversais , Revisões Sistemáticas como Assunto , Açúcares , Bebidas/efeitos adversos
4.
Int J Biol Macromol ; 222(Pt A): 783-793, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36174864

RESUMO

The bacterial infection and its transmission pose a great threat to life and health, which leads to the urgent development of efficient and broad-spectrum antibacterial agents. Herein, Ag/lignin layered nanoflower (Ag/EHL-CM-0.05) was synthesized by using biomass lignin as reducing and capping agents and silver nitrate as precursor. The study showed that the size distribution of Ag NPs was uniform distribution and about 20-40 nm. The crystal surface of Ag NPs was Ag (111) surface. The minimum inhibitory concentration of Ag/EHL-CM-0.05 against E. coli and S. aureus was all 7.8 µg/mL, which was the lowest of other Ag/lignin antibacterial materials and reached a level nearly as polycationic antibacterial agents. The antibacterial mechanism suggested that Ag/EHL-CM-0.05 could release OH and Ag+, which could cause bacterial death. Finally, Ag/EHL-CM-0.05 was sprayed onto the viscose fabrics by liquid-phase spray deposition method. It was found that the inhibition zone diameter of modified viscose fabrics against E. coli and S. aureus only dropped about 0.16 cm on average after friction treatment and 0.32 cm on average after washing treatment. This work provides a new idea for the design and synthesize of efficient, broad-spectrum, and bio-compatible antibacterial agents, which has important social, economic, and environmental significance.


Assuntos
Nanopartículas Metálicas , Staphylococcus aureus , Escherichia coli , Lignina/farmacologia , Nanopartículas Metálicas/química , Antibacterianos/farmacologia , Antibacterianos/química
5.
Blood Coagul Fibrinolysis ; 25(8): 876-82, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25192241

RESUMO

Conjugation of polyethylene glycol (PEG) to another molecule prolongs its half-life in the body, but has a potential to artifactually increase the activated partial thromboplastin time (aPTT) as measured with certain assays. Studies conducted in-house at Bristol-Myers Squibb using the STA-PTT Automate 5 assay, the routine assay used to measure aPTT, demonstrated prolongation of aPTT in plasma samples spiked in vitro with 40-kDa branched PEG (PEG40) conjugated compounds or PEG40 alone, but not in samples spiked with vehicle or non-PEGylated compound, suggesting that the interference is because of the PEG40 moiety. To investigate the cause of this phenomenon, cynomolgus monkey and rat plasma samples were spiked with different concentrations of PEG40 and the aPTT was measured using different proprietary assays. With one exception, prolongation of aPTT was observed with all assays containing silica as the contact activator. No changes in aPTT were noted in assays using kaolin as a contact activator. The findings indicated that the observed prolongation of aPTT is largely because of interference of PEG40 with the silica, but other features of the reagent mixture may also influence aPTT times.


Assuntos
Artefatos , Bioensaio/normas , Coagulação Sanguínea , Indicadores e Reagentes/química , Plasma/química , Polietilenoglicóis/química , Animais , Automação Laboratorial , Meia-Vida , Humanos , Caulim/química , Cinética , Macaca fascicularis , Tempo de Tromboplastina Parcial , Ratos , Dióxido de Silício/química , Tromboelastografia
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