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1.
Mikrochim Acta ; 191(7): 384, 2024 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-38861028

RESUMO

Multifunctional N, Fe-doped carbon dots (N, Fe-CDs) were synthesized by the one-step hydrothermal method using ferric ammonium citrate and dicyandiamide as raw materials. The N, Fe-CDs exhibited peroxidase-like (POD) activity by catalyzing the oxidization of 3,3',5,5'-tetramethylbenzidine (TMB) to the green oxidation state ox-TMB in the presence of hydrogen peroxide (H2O2). Subsequently, based on the POD activity of N, Fe-CDs, an efficient and sensitive colorimetric method for the detection of H2O2 and ascorbic acid (AA) was established with a limit of detection of 0.40 µM and 2.05 µM. The proposed detection method has been successfully applied to detect AA in fruit juice, vitamin C tablets, and human serum samples and has exhibited excellent application prospects in biotechnology and food fields. Furthermore, N, Fe-CDs also showed a protective effect on the cell damage caused by H2O2 and could be used as an antioxidant agent.


Assuntos
Ácido Ascórbico , Carbono , Sucos de Frutas e Vegetais , Peróxido de Hidrogênio , Oxirredução , Pontos Quânticos , Peróxido de Hidrogênio/química , Ácido Ascórbico/química , Humanos , Carbono/química , Pontos Quânticos/química , Sucos de Frutas e Vegetais/análise , Benzidinas/química , Colorimetria/métodos , Limite de Detecção , Ferro/química , Nitrogênio/química , Peroxidase/química , Peroxidase/metabolismo , Antioxidantes/química , Antioxidantes/farmacologia
2.
Analyst ; 148(15): 3518-3523, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37417917

RESUMO

Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is a universal method for the quantitative analysis of small molecular drugs in therapeutic drug monitoring (TDM). Alternatively, liquid chromatography-miniature mass spectrometry (LC-Mini MS) is a simple operating technique for quantitative analysis. However, the wide chromatographic peaks and long retention times of TDM samples using the LC-Mini MS system deteriorated the accuracy and efficiency of quantitative analysis. Here, an optimized electrospray ionization (ESI) interface setup with a splitter valve and a capillary needle (I.D. 30 µm and O.D. 150 µm) of the LC-Mini MS system was acquired. The chromatographic peaks were narrower and smoother and the retention time was shorter for TDM compounds. Furthermore, a quantitative analysis method for risperidone and the active metabolite 9-hydroxyrisperidone in plasma was developed based on this optimal LC-Mini MS setup. The results showed that the calibration curves of risperidone and 9-hydroxyrisperidone had good linear ranges of 2-100 ng mL-1 (R2 = 0.9931) and 2-100 ng mL-1 (R2 = 0.9915), respectively. Finally, the matrix effects, recoveries and stability of risperidone and 9-hydroxyrisperidone samples were analyzed. The results satisfied the requirements of quantitative validation in routine TDM procedures.


Assuntos
Palmitato de Paliperidona , Risperidona , Risperidona/análise , Cromatografia Líquida/métodos , Isoxazóis/análise , Pirimidinas , Espectrometria de Massas em Tandem/métodos , Reprodutibilidade dos Testes , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos
3.
Analyst ; 148(15): 3666-3676, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37431281

RESUMO

Photoelectrochemical sensors have outstanding advantages including high sensitivity and miniaturization for outdoor use. Recently, perovskite quantum dots have attracted significant attention due to their high photoluminescence quantum yield. Nonetheless, there is still a strong need to improve their performance in challenging aqueous biological applications. In this paper, based on the molecularly imprinted polymer encapsulation of CsPbBr3 perovskite quantum dot/TiO2 inverse opal heterojunction structures, linear photoelectrochemical detection of cholesterol in aqueous solution was obtained without the involvement of an enzyme. The attenuation of photocurrent intensity under intermittent irradiation within 900 s (45 on/off cycles) was only 8.6%, demonstrating the superior stability of CsPbBr3 based sensor here. At the same time, the minimum detection limit of 1.22 × 10-9 mol L-1 in buffer conditions was lower than that reported for cholesterol photoelectric sensors. It has also been shown that the photoelectrochemical sensor of CsPbBr3 here outperformed that of CH3NH3PbBr3, which is another important member of the perovskite family. Finally, the proposed photoelectrochemical sensor platform was successfully applied in the determination of cholesterol in challenging serum with satisfactory recovery. The synergism among CsPbBr3 perovskite quantum dots, TiO2 inverse opal structure and imprinted polymer has led to greatly improved water stability, super selectivity and sensitivity, thus promoting the development of perovskite-based biological sensors.

4.
Nanotechnology ; 34(12)2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36548986

RESUMO

Recently, carbon dots (CDs) have exhibited promising applications in the fluorescence detection of various ions and biomolecules. In this work, one kind of nitrogen-doped CDs (N-CDs) with high fluorescence intensity was synthesized, characterized by transmission electron microscopy, x-ray diffraction, x-ray photoelectron spectroscopy, Fourier-transform infrared, UV-vis absorption spectra, and fluorescence spectra. The results show that the spherical and uniform N-CDs (quantum yield: 60.2%) have remarkable fluorescence properties and photostability, which makes N-CDs can be utilized as an 'on-off-on' sensor for Hg2+and glutathione (GSH). In addition, the pH-sensitive behavior of N-CDs makes it also applicable to H+detection under acid conditions (pKa = 3.53). The linear range of the 'turn-off' sensor detecting Hg2+was 0.014-50µM, with a 0.014µM limit of detection (LOD). GSH was detected by the fluorescence 'turn-on' method with a linear range of 0.125-60µM and a LOD of 0.125µM. The outstanding performance of N-CDs makes it potential applications in ecological pollution and biomolecule visualization monitoring.


Assuntos
Mercúrio , Pontos Quânticos , Corantes Fluorescentes/química , Carbono/química , Pontos Quânticos/química , Espectrometria de Fluorescência/métodos , Glutationa , Íons , Nitrogênio/química , Concentração de Íons de Hidrogênio
5.
BMC Infect Dis ; 23(1): 264, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37101288

RESUMO

OBJECTIVES: This study aimed to identify the related risk factors and potential predictors of SARS-CoV-2 RNA negative conversion by describing the dynamics of viral shedding in infected children admitted to two hospitals from Shanghai during the Omicron variant outbreak. METHODS: This retrospective cohort included laboratory-confirmed cases of SARS-CoV-2 infection from Shanghai between March 28 and May 31, 2022. Clinical characteristics, personal vaccination, and household vaccination rates were collected through electronic health records and telephone interviews. RESULTS: A total of 603 paediatric patients confirmed to have COVID-19 were included in this study. Both univariate and multivariate analyses were performed to filter independent factors for the duration to viral RNA negative conversion. Data on the redetection of SARS-CoV-2 in the patients after they showed negative results on the RT‒PCR test (intermittent negative status) were also analysed. The median duration of virus shedding was 12 (interquartile range, IQR: 10-14) days. The severity of clinical outcome, personal vaccination-2doses, household vaccination rates, and abnormal defecation were factors indecently affecting negative conversion of SARS-CoV-2 RNA, suggesting that patients who had abnormal defecation or with more severe conditions would have delayed virological clearance, while patients who previously had 2 doses of vaccination or had higher household vaccination rates would have accelerated virological clearance. Loss of appetite (odds ratio (OR): 5.343; 95% CI: 3.307-8.632) and abnormal defecation (OR: 2.840; 95% CI: 1.736-4.645) were significantly associated with intermittent negative status. CONCLUSION: These findings could provide clues for the early identification of paediatric patients with prolonged viral shedding and could enrich the evidence for the development of prevention and control strategies, especially vaccination policies for children and adolescents.


Assuntos
COVID-19 , Dispepsia , Adolescente , Humanos , Criança , Criança Hospitalizada , RNA Viral/genética , SARS-CoV-2/genética , Estudos Retrospectivos , China/epidemiologia , COVID-19/epidemiologia
6.
J Fluoresc ; 33(2): 459-469, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36441340

RESUMO

Carbon dots (CDs) have excellent fluorescence properties and can be used in many research fields. In this paper, carbon dots were prepared by microwave-assisted pyrolysis of citric acid and urea, characterized by transmission electron microscope (TEM), X-ray diffractometer (XRD), 13C-NMR spectrum, zeta potential, Fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible (UV-vis) absorption and fluorescence spectra, and detected the Hg2+ and ascorbic acid (AA) sequentially. It showed that carbon dots were hollow, spherical particles and less than 10 nm, photoluminescence quantum yield of carbon dots was about 15%. The CDs were selective and sensitive to Hg2+ and AA based on the "on-off-on" fluorescence behavior. The detection limits of CDs for Hg2+ and AA were 0.138 µM and 0.212 µM, respectively. Fluorescence response mechanism of CDs was also discussed.


Assuntos
Mercúrio , Pontos Quânticos , Ácido Ascórbico , Pontos Quânticos/química , Carbono/química , Espectroscopia de Infravermelho com Transformada de Fourier , Espectrometria de Fluorescência , Corantes Fluorescentes/química
7.
Altern Ther Health Med ; 29(5): 396-399, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37171949

RESUMO

Background: To investigate the value of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in the diagnosis of lung nodules related enlarged mediastinal lymph nodes (MLNs). Methods: Clinical data of 108 patients with lung nodules related enlarged MLNs who underwent EBUS-TBNA in our single center were retrospectively analyzed from January 2020 to December 2021. The sensitivity and specificity of EBUS-TBNA in malignancy diagnosis were evaluated. Associations between ultrasonic image measurement indexes and malignancy diagnosis were explored. The receiver operating characteristic (ROC) curve of these indexes, the area under curve (AUC), and the corresponding cut-off values were calculated to predict malignant MLNs. Results: Sensitivity, specificity, and accuracy of EBUS-TBNA in the diagnosis of lung nodules related malignant MLNs were 89.47%, 100%, and 92.59%, respectively. There were significantly higher proportions of malignant MLNs with clear boundary, short diameter ≥1 cm, lower long to short diameter ratio, abundant flow of blood, and destructed medulla than that of benign ones (P < .05). According to ROC curve analysis, the cut-off value of short diameters for predicting malignant MLNs was 1.085 cm, and the AUC was 0.796 (95% confidence interval: 0.724-0.868, P < .001). Corresponding sensitivity and specificity were 61.36% and 80.00%, respectively. The cut-off value of the long to short diameter ratio for predicting malignancy was 1.405, and the AUC was 0.697 (95% confidence interval: 0.609-0.790, P < .001). Corresponding sensitivity and specificity were 70.00% and 71.97%, respectively. Conclusion: EBUS-TBNA has a satisfactory accuracy of lung nodules related MLNs diagnosis. Short diameters and long to short diameter ratio of lung nodules related MLNs in ultrasonic image may contribute to the prediction of malignant lymph nodes.


Assuntos
Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Estudos Retrospectivos , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Pulmão
8.
J Mol Recognit ; 34(12): e2934, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34553439

RESUMO

Aptamers have gained significant attention as the molecular recognition element to replace antibodies in sensor development and target delivery. Nevertheless, it is noteworthy that unlike the wide application of polyvalent antibodies, existing researches on the combined use of heterologous aptamers with similar recognition affinity and specificity for target detection were sporadic. Herein, first, the wide existence of polyaptamer for bacteria was revealed through the summary of existing literature. Furthermore, based on the establishment of a sensitive aptamer cocktail/graphene oxide fluorescence resonance energy transfer polyaptasensor with a detection limit as low as 10 CFU/ml, the systemic characterization of aptamer cocktails in bacterial detection was carried out by taking E. coli, Vi. parahemolyticus, S. typhimurium, and C. sakazakii as the assay targets. It was turned out that the polyaptasensors for C. sakazakii and S. typhimurium owned prevalence in the broader concentration range of target bacteria. While the polyaptasensors for E. coli and V. parahemolyticus outperformed monoaptasensor mainly in the lower concentration of target bacteria. The linear relationships between fluorescence recovery and the concentration of bacteria were also discussed. The different characteristics of the bacterial cellular membrane, including the binding affinity and the robustness to variation, are analyzed to be the main reason for the diverse detection performance of aptasensors. The study here enhances a sensor detection strategy with super sensitivity. More importantly, this systemic study on the aptamer cocktail in reference to antibodies will advance the in-depth understanding and rational design of aptamer based biological recognition, detection, and targeting.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Grafite , Aptâmeros de Nucleotídeos/química , Escherichia coli/genética , Escherichia coli/metabolismo , Transferência Ressonante de Energia de Fluorescência , Grafite/química , Limite de Detecção
9.
Amino Acids ; 53(7): 1065-1077, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34085155

RESUMO

An 8-week feeding trial was conducted to evaluate optimum dietary methionine (Met) requirement of juvenile humpback grouper (Cromileptes altivelis) and the influence of dietary methionine (Met) supplementations on growth, gut micromorphology, protein and lipid metabolism. Seven isoproteic (48.91%) and isolipidic diets (10%) were made to contain 0.70, 0.88, 1.04, 1.27 1.46, 1.61 and 1.76% of dry matter Met levels. Results showed that lower survival, weight gain (WG%), protein efficiency ratio (PER), protein productive value (PPV) but higher daily feed intake (DFI) and feed conversion ratio (FCR) were observed in the Met deficient groups (0.70 and 0.88%). Optimum dietary Met requirement for humpback grouper was found to be 1.07% through the straight-broken line analysis of WG% against Met. Fish fed Met deficient diets (0.70, 0.88%) exhibited lower mRNA levels of growth hormone (GH), growth hormone receptor (GHR), insulin-like growth factor-I (IGF-1), target of rapamycin (TOR) as well as S6 kinase 1 (S6K1) than other dietary groups. Whereas, expression of genes related to general control nonderepressible (GCN2) kinase i.e., GCN2 and C/EBPß enhancer-binding protein ß was upregulated in fish fed low Met diets (P < 0.05). The mRNA expression of hepatic fatty acid synthase (FAS) and sterol regulatory element-binding protein-1 (SREBP-1) were higher in fish fed 0.70 and 0.88% dietary Met group and the lipolytic genes, hepatic peroxisome proliferator-activated receptor α (PPARα) and carnitine palmitoyl transferase-1 (CPT-1) showed an opposite variation tendency as FAS or SREBP1. Generally, the optimum Met requirement for humpback grouper was predicted to be 1.07% of dry matter.


Assuntos
Ração Animal/análise , Bass/anatomia & histologia , Bass/crescimento & desenvolvimento , Proteínas de Peixes/metabolismo , Metabolismo dos Lipídeos , Metionina/metabolismo , Necessidades Nutricionais , Animais , Bass/metabolismo , Dieta , Proteínas de Peixes/genética , Fígado/metabolismo
10.
Gen Comp Endocrinol ; 307: 113744, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33705742

RESUMO

The carnivorous teleost fish is often intolerant to high levels of postprandial plasma glucose. This study aimed to evaluate the effects of insulin-like growth factor-1 (IGF-1) and growth hormone (GH) administrations on plasma glucose levels and expression of glucose transporters (GLUTs) in various tissues of hybrid grouper, and hence to further clarify the hormone-GLUTs-plasma glucose regulating axis. Twenty-four experimental fish (average body weight: 77.5 ± 5.4 g) were selected and injected with recombinant human IGF-1 (0.2 µg/g body weight) and PBS (0.01 mol/L) in enterocoelia, respectively, and in the GH injected experiment, the same quantity of fish (average body weight: 103.8 ± 5.8 g) were administrated with GH at a dose of 0.5 µg/g body weight or with PBS at a dose of 0.01 mol/L. Results showed that plasma glucose level was significantly (P < 0.05) declined by the IGF-1 administration but elevated by the GH administration. Plasma IGF-1 concentration was significantly (P < 0.01) elevated by the IGF-1 administration, while GH concentration did not significantly (P ≥ 0.05) respond to the GH administration. The relative mRNA levels of insulin-like growth factor-1 receptor a (IGF-Ra) in liver and muscle were decreased significantly with the IGF-1 administration, and a similar variation tendency was also found in insulin-like growth factor-1 receptor b (IGF-Rb) in liver, muscle and adipose tissues. Besides, the relative mRNA level of insulin receptor (IRS) in liver was significantly increased in the IGF-1 administrated group. After the GH administration, the mRNA levels of hepatic growth factor receptor 2 (GHR2) and IGF-1 were significantly elevated. As for GLUTs, the relative mRNA levels of GLUT1 and GLUT2 in liver were obviously elevated by the IGF-1 administration, while the mRNA level of GLUT4 in muscle was reduced. In liver, the protein levels of GLUT1, 2 and 4 were significantly elevated by the IGF-1 administration, and in adipose, only GLUT1 was observed to have a significantly increased protein level. The mRNA expression of GLUTs was less affected by the GH administration. The protein level of GLUT1 in liver was significantly reduced by the GH administration, while in adipose, it was significantly increased. The protein level of GLUT2 in liver or adipose showed an opposite variation as that of GLUT1. Overall, IGF-1 had a hypoglycemic effect on hybrid grouper, and this probably was through up-regulating the protein levels of hepatic GLUT1, 2 and 4 and adipose GLUT1. GH showed an opposite role in regulating plasma glucose level as IGF-1.


Assuntos
Bass , Glicemia , Proteínas Facilitadoras de Transporte de Glucose , Fator de Crescimento Insulin-Like I , Animais , Dieta , Feminino , Glucose , Hormônio do Crescimento , Hormônios , Humanos , Fator de Crescimento Insulin-Like I/genética , Fígado , Masculino
11.
Chirality ; 32(9): 1178-1185, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32623797

RESUMO

Herein, we describe a new chiral amorphous metal-organic polyhedra used as the stationary phase for high-resolution gas chromatography (GC). The chiral stationary phase was coated onto a capillary column via a dynamic coating process and investigated for a variety of compounds. The experimental results showed that the chiral stationary phase exhibits good selectivity for linear alkanes, linear alcohols, polycyclic aromatic hydrocarbons, isomers, and chiral compounds. In addition, the column has the advantages of high column efficiency and short analysis time. The present work indicated that amorphous metal-organic polyhedra have great potential for application as a new type of stationary phase for GC.

12.
Neurol Sci ; 40(12): 2617-2624, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31392639

RESUMO

BACKGROUND AND AIMS: Whether fluid-attenuated inversion recovery (FLAIR) vascular hyperintensities (FVH)-DWI mismatch could predict the outcome or not remains in debate. The aim of this study was to identify if FVH combined with the other markers improved favorable outcome prediction of acute infarctions in patients with unilateral acute internal carotid artery (ICA) occlusion. METHODS: Consecutive 68 adult acute middle cerebral artery (MCA) territory infarction patients caused by acute ICA occlusion, including favorable (n = 38, mRS ≤ 2) and unfavorable (n = 30, mRS > 2) groups, were enrolled in this retrospective analysis. The diagnostic efficiency of favorable clinical outcome of FVH-DWI mismatch was compared with those of DWI lesions volumetry and the combined marker of FVH-DWI mismatch and other factors. RESULTS: There were more prominent FVH-DWI mismatch (≥ 3 sections) (84%), less atrial fibrillation (AFib) (13%), and more tandem MCA normal or mild stenosis (63%) in favorable outcome group than those (30%, 40%, and 27%, respectively) in unfavorable group. Univariate and multivariate analyses showed that the prominent FVH-DWI mismatch was the positive predictive factor for favorable outcome (OR = 2.643 and 3.200). Prominent FVH-DWI mismatch, in combination with tandem MCA normal or mild stenosis, and absence of Afib, had better performance (AUC = 0.875) than that of initial DWI lesion volumetry (AUC = 0.854) and any other single factor (AUC = 0.634~0.820) in predicting favorable outcome. CONCLUSIONS: Prominent FVH-DWI mismatch was associated with favorable outcome in acute infarctions in unilateral ICA occlusion patients. Its predictive performance would be improved when combined with the assessment of tandem lesions of MCA and AFib.


Assuntos
Fibrilação Atrial/diagnóstico , Estenose das Carótidas/diagnóstico , Infarto da Artéria Cerebral Média/diagnóstico , Imageamento por Ressonância Magnética/normas , Avaliação de Resultados em Cuidados de Saúde , Doença Aguda , Idoso , Fibrilação Atrial/terapia , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/terapia , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Infarto da Artéria Cerebral Média/terapia , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos
13.
Anal Biochem ; 539: 48-53, 2017 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-29031457

RESUMO

Pneumatic micro-valve controlled microfluidic chip provides precise fluidic control for cell manipulation. In this paper, a multi-functional microfluidic chip was designed for three separate experiments: 1. Different cell lines were dispensed and cultured; 2. Three transfected SH-SY5Y cells were introduced and treated with methyl-phenyl-pyridinium (MPP+) as drug delivery mode; 3. Specific protection and interaction were observed among cell co-culture after nerve damage. The outcomes revealed the potential and practicability of our entire multi-functional pneumatic chip system on different cell biology applications.


Assuntos
Técnicas de Cocultura/métodos , Dispositivos Lab-On-A-Chip , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Cocultura/instrumentação , Dopamina/metabolismo , Portadores de Fármacos/química , Humanos , Neurotoxinas/toxicidade , Agregados Proteicos , Compostos de Piridínio/química , Compostos de Piridínio/toxicidade , alfa-Sinucleína/química , alfa-Sinucleína/metabolismo
14.
Analyst ; 142(22): 4257-4264, 2017 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-28835953

RESUMO

Rapid screening of active compounds plays a crucial role in the research and application of complex natural medicines. Herein, a new method of simultaneous label-free multi-drug screening based on a selective aptamer-carboxyfluorescein/graphene oxide energy transfer optical sensor combined with microfluidic chip electrophoretic separation is reported. In this study, seven traditional Chinese medicinal monomers were chosen as targets for the screening of G-quadruplex ligands. The screening results of the G-quadruplex active ligands, including daidzein, berberine hydrochloride, jatrorrhizine hydrochloride, and fangchinoline, and non-active ligands, including geniposide and oxymatrine, were consistent with those reported in literature. Moreover, one new potential G4DNA active drug, jujuboside A, was identified. Molecular simulation of the interaction between G4DNA and drugs was also carried out using HyperChem and AutoDock to verify the results of the experimental screening. It further demonstrated the reliability of our strategy. This novel separation and concentration based multi-sensing strategy provides a simple, rapid, and sensitive tool for simultaneous multi-drug screening, which is very meaningful for drug screening and bio-interaction analysis.


Assuntos
Técnicas Biossensoriais , Avaliação Pré-Clínica de Medicamentos/métodos , Eletroforese , Quadruplex G , Microfluídica , Aptâmeros de Nucleotídeos , Transferência de Energia , Fluoresceínas , Grafite , Ligantes , Reprodutibilidade dos Testes , Saponinas
15.
J Nanobiotechnology ; 15(1): 42, 2017 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-28578696

RESUMO

BACKGROUND: Iron deficiency in children can have significant neurological consequences, and iron supplementation is an effective treatment of choice. However, traditional routes of iron supplementation do not allow efficient iron delivery to the brain due to the presence of the blood-brain barrier. So an easily delivered iron formulation with high absorption efficiency potentially could find widespread application in iron deficient infants. RESULTS: In this study, we have developed and characterized a nanovesicular formulation of ferric ammonium citrate (ferric ammonium citrate nanoliposomes, FAC-LIP) and have shown that it can increase brain iron levels in rats following nasal administration. FAC was incorporated into liposomes with high efficiency (97%) and the liposomes were small (40 nm) and stable. Following intranasal delivery in rats, FAC-LIP significantly increased the iron content in the olfactory bulb, cerebral cortex, striatum, cerebellum and hippocampus, and was more efficient at doing so than FAC alone. No signs of apoptosis or abnormal cell morphology were observed in the brain following FAC-LIP administration, and there were no significant changes in the levels of SOD and MDA, except in the cerebellum and hippocampus. No obvious morphological changes were observed in lung epithelial cells or tracheal mucosa after nasal delivery, suggesting that the formulation was not overtly toxic. CONCLUSIONS: In this study, nanoscale FAC-LIP proved an effective system delivering iron to the brain, with high encapsulation efficiency and low toxicity in rats. Our studies provide the foundation for more detailed investigations into the applications of niosomal nasal delivery of liposomal formulations of iron as a simple and safe therapy for iron deficiency anemia. Graphical abstract The diagrammatic sketch of "Nasal delivery of nanoliposome-encapsulated ferric ammonium citrate can increase the iron content of rat brain". Nanoliposome-encapsulated ferric ammonium citrate (FAC-LIP) was successfully prepared and intranasal administration of FAC-LIP increased both the total iron contents and iron storage protein (FTL) expression in rat olfactory bulb, cerebral cortex, striatum and hippocampus, compared with those of FAC groups. Moreover, there was not overtly toxic affects to brain, lung epithelial cells and tracheal mucosa.


Assuntos
Encéfalo/metabolismo , Compostos Férricos/administração & dosagem , Compostos Férricos/farmacocinética , Compostos de Amônio Quaternário/administração & dosagem , Compostos de Amônio Quaternário/farmacocinética , Administração Intranasal , Animais , Apoptose/efeitos dos fármacos , Encéfalo/citologia , Encéfalo/efeitos dos fármacos , Ferro/administração & dosagem , Ferro/farmacocinética , Lipossomos/química , Lipossomos/ultraestrutura , Masculino , Malondialdeído/metabolismo , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo
16.
Analyst ; 141(13): 4142-50, 2016 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-27163941

RESUMO

Although a flow cytometer, being one of the most popular research and clinical tools for biomedicine, can analyze cells based on the cell size, internal structures such as granularity, and molecular markers, it provides little information about the physical properties of cells such as cell stiffness and physical interactions between the cell membrane and fluid. In this paper, we propose a computational cell analysis technique using cells' different equilibrium positions in a laminar flow. This method utilizes a spatial coding technique to acquire the spatial position of the cell in a microfluidic channel and then uses mathematical algorithms to calculate the ratio of cell mixtures. Most uniquely, the invented computational cell analysis technique can unequivocally detect the subpopulation of each cell type without labeling even when the cell type shows a substantial overlap in the distribution plot with other cell types, a scenario limiting the use of conventional flow cytometers and machine learning techniques. To prove this concept, we have applied the computation method to distinguish live and fixed cancer cells without labeling, count neutrophils from human blood, and distinguish drug treated cells from untreated cells. Our work paves the way for using computation algorithms and fluidic dynamic properties for cell classification, a label-free method that can potentially classify over 200 types of human cells. Being a highly cost-effective cell analysis method complementary to flow cytometers, our method can offer orthogonal tests in companion with flow cytometers to provide crucial information for biomedical samples.


Assuntos
Citometria de Fluxo , Técnicas Analíticas Microfluídicas , Algoritmos , Linhagem Celular Tumoral , Tamanho Celular , Humanos , Neutropenia/diagnóstico , Neutrófilos/citologia
17.
Nanomedicine ; 12(7): 1747-1755, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27112306

RESUMO

The absorption mechanism of heme iron remains unclear due to the limit of labeling techniques. Quantum dots (QDs) are powerful fluorescent probes resistant to photobleaching, however, there is no data about the application of QDs in heme iron absorption. Herein, we prepared hemin-coated CdSe/ZnS (QDs-hemin), and studied their absorption in vitro and in vivo. Results showed that QDs-hemin had uniform particle sizes, physiological stability and high joint efficiency. Moreover, QDs-hemin could be successfully absorbed gradually into the duodenum with the time using synchrotron radiation micro X-ray fluorescence and confocal laser scanning microscopy. Furthermore, QDs-hemin were observed to degrade in lysosomes, and their absorption was blocked by Heme Carrier Protein 1 (HCP1) antibody and HCP1 siRNA. All the results demonstrate that QDs can be a good tracer for heme iron and that HCP1 pathway is critical and predominant over the endocytosis pathway in the absorption mechanism.


Assuntos
Hemina/farmacocinética , Pontos Quânticos , Animais , Duodeno , Corantes Fluorescentes , Ferro , Camundongos , Tamanho da Partícula , Proteína-Arginina N-Metiltransferases
18.
Infect Immun ; 83(4): 1715-31, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25605761

RESUMO

Microsporidia are obligate intracellular parasites with rigid spore walls that protect against various environmental pressures. Despite an extensive description of the spore wall, little is known regarding the mechanism by which it is deposited or the role it plays in cell adhesion and infection. In this study, we report the identification and characterization of two novel spore wall proteins, SWP7 and SWP9, in the microsporidian species Nosema bombycis. SWP7 and SWP9 are mainly localized to the exospore and endospore of mature spores and the cytoplasm of sporonts, respectively. In addition, a portion of SWP9 is targeted to the spore wall of sporoblasts earlier than SWP7 is. Both SWP7 and SWP9 are specifically colocalized to the spore wall in mature spores. Furthermore, immunoprecipitation, far-Western blotting, unreduced SDS-PAGE, and yeast two-hybrid data demonstrated that SWP7 interacted with SWP9. The chitin binding assay showed that, within the total spore protein, SWP9 and SWP7 can bind to the deproteinated chitin spore coats (DCSCs) of N. bombycis. However, binding of the recombinant protein rSWP7-His to the DCSCs is dependent on the combination of rSWP9-glutathione S-transferase (GST) with the DCSCs. Finally, rSWP9-GST, anti-SWP9, and anti-SWP7 antibodies decreased spore adhesion and infection of the host cell. In conclusion, SWP7 and SWP9 may have important structural capacities and play significant roles in modulating host cell adherence and infection in vitro. A possible major function of SWP9 is as a scaffolding protein that supports other proteins (such as SWP7) that form the integrated spore wall of N. bombycis.


Assuntos
Bombyx/microbiologia , Adesão Celular/fisiologia , Proteínas Fúngicas/metabolismo , Interações Hospedeiro-Patógeno/imunologia , Nosema/patogenicidade , Esporos Fúngicos/patogenicidade , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Parede Celular/metabolismo , Proteínas Fúngicas/genética , Dados de Sequência Molecular , Nosema/metabolismo , Ligação Proteica , Alinhamento de Sequência , Análise de Sequência de DNA , Esporos Fúngicos/metabolismo
19.
Gynecol Obstet Invest ; 79(2): 97-100, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25634306

RESUMO

BACKGROUND/AIMS: Acute fatty liver of pregnancy (AFLP) is a severe liver failure condition that has limited therapeutic approaches. We aimed to evaluate the efficacy of combining plasma exchange (PE) and plasma perfusion (PP) with conventional therapy for the treatment of AFLP using a retrospective analysis. METHODS: Among 22 patients with AFLP, 16 cases were treated with conventional treatment (CT group), while the other 6 cases were treated with PE and PP in addition to conventional therapy (CT+PE+PP group). Treatment efficacy was based primarily on survival and secondarily on liver and kidney functions 2 weeks after treatment. Adverse effects were also assessed at the same time point. RESULTS: In the CT+PE+PP group, 5 (83.3%) patients improved, while 1 (16.7%) patient died of multiple organ dysfunction syndrome. In the CT group, 3 (18.75%) patients improved, while 13 (81.2%) patients died of complications. Liver and kidney functions and survival were significantly improved in the CT+PE+PP group (p < 0.05) compared to the CT group. CONCLUSIONS: Timely application of PE and PP in the early phase of AFLP may be a promising treatment to halt or reverse the progression of AFLP.


Assuntos
Fígado Gorduroso/terapia , Hemoperfusão/métodos , Troca Plasmática/métodos , Complicações na Gravidez/terapia , Adulto , Terapia Combinada , Feminino , Humanos , Gravidez , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
20.
Analyst ; 139(11): 2890-5, 2014 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-24755615

RESUMO

A new type of high-throughput and parallel optical sensing platform with a single-color probe based on microfluidic chip electrophoresis combined with aptamer-carboxyfluorescein/graphene oxide energy transfer is reported here. Label-free protein multi-targets were detected, even in challenging complex samples without any pre-treatment.


Assuntos
Eletroforese em Microchip/métodos , Grafite/química , Microfluídica/instrumentação , Proteínas/análise , Aptâmeros de Nucleotídeos/genética , Espectrometria de Fluorescência , Trombina/genética
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