Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
World J Gastroenterol ; 27(21): 2910-2920, 2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34135561

RESUMO

BACKGROUND: Persistent liver inflammatory damage is the main risk factor for developing liver fibrosis, cirrhosis, and even hepatocellular carcinoma in chronic hepatitis B (CHB) patients. Thus, accurate prediction of the degree of liver inflammation is a high priority and a growing medical need. AIM: To build an effective and robust non-invasive model for predicting hepatitis B-related hepatic inflammation. METHODS: A total of 650 treatment-naïve CHB (402 HBeAg-positive and 248 HBeAg-negative) patients who underwent liver biopsy were enrolled in this study. Histological inflammation grading was assessed by the Ishak scoring system. Serum quantitative hepatitis B core antibody (qAnti-HBc) levels and 21 immune-related inflammatory factors were measured quantitatively using a chemiluminescent microparticle immunoassay. A backward feature elimination (BFE) algorithm utilizing random forest (RF) was used to select optional features and construct a combined model. The diagnostic abilities of the model or variables were evaluated based on the estimated area under the receiver operating characteristics curve (AUROC) and compared using the DeLong test. RESULTS: Four features were selected to predict moderate-to-severe inflammation in CHB patients using the RF-BFE method. These predictive features included qAnti-HBc, ALT, AST, and CXCL11. Spearman's correlation analysis indicated that serum qAnti-HBc, ALT, AST, and CXCL11 levels were positively correlated with the histology activity index (HAI) score. These selected features were incorporated into the model to establish a novel model named I-3A index. The AUROC [0.822; 95% confidence interval (CI): 0.790-0.851] of the I-3A index was significantly increased compared with qAnti-HBc alone (0.760, 95%CI: 0.724-0.792, P < 0.0001) in all CHB patients. The use of an I-3A index cutoff value of 0.41 produced a sensitivity of 69.17%, specificity of 81.44%, and accuracy of 73.8%. Additionally, the I-3A index showed significantly improved diagnostic performance for predicting moderate-to-severe inflammation in HBeAg-positive and HBeAg-negative CHB patients (0.829, 95%CI: 0.789-0.865 and 0.810, 95%CI: 0.755-0.857, respectively). CONCLUSION: The selected features of the I-3A index constructed using the RF-BFE algorithm can effectively predict moderate-to-severe liver inflammation in CHB patients.


Assuntos
Hepatite B Crônica , Alanina Transaminase , Algoritmos , Biomarcadores , Antígenos E da Hepatite B , Vírus da Hepatite B/genética , Hepatite B Crônica/complicações , Hepatite B Crônica/diagnóstico , Humanos , Inflamação , Cirrose Hepática/diagnóstico , Curva ROC
2.
Heart Surg Forum ; 22(1): E015-E018, 2019 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-30802191

RESUMO

BACKGROUND: To investigate the roles of microembolus and plasma D-dimer in evaluating the warfarin anticoagulant therapy efficacies for patients with atrial fibrillation (AF). METHODS: Fifty-six AF patients were treated with aspirin antiplatelet therapy (Group ASP) and forty AF patients were treated with warfarin anticoagulant therapy (Group WAR). The microemboli and plasma D-dimer in these two groups were monitored and compared before and after treatment. RESULTS: Group ASP had 21 and 17 cases with positive microemboli before and after treatment, respectively, and there was no significant difference in the detection rate of microemboli before and after treatment; Group WAR had 14 and 5 cases with positive microemboli before and after treatment, respectively, and the detection rate of microemboli was significantly reduced after treatment. The levels of plasma D-dimer in the two groups were significantly reduced after treatment (327±73 µg/L vs 235±61 µg/L and 313±81 µg/L vs 170±67 µg/L, respectively, P<0.05), among which the reduction level in Group WAR was more significant. CONCLUSIONS: Microemboli and D-dimer can be used as the indicators for evaluating the embolism risk and therapeutic efficacies in AF patients.


Assuntos
Fibrilação Atrial/tratamento farmacológico , Embolia/prevenção & controle , Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Varfarina/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/administração & dosagem , Fibrilação Atrial/sangue , Fibrilação Atrial/complicações , Biomarcadores/sangue , Relação Dose-Resposta a Droga , Embolia/sangue , Embolia/etiologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
3.
Talanta ; 171: 90-100, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28551159

RESUMO

This work illustrates an accurate method for determination of Se by electrolytic hydride generation technique based on a novel carbon paste electrode for sample introduction combined with atomic fluorescence spectral analysis. The studies show that Se(IV) can be converted efficiently to SeH2 on an L-cysteine modified carbon paste electrode (CMCPE), which has never been reported before. Significantly, generation from Se(IV) implies that the use of carbon paste electrode-based electron-induced hydride generation system to achieve efficiency is almost 90% to that obtained by chemical hydride generation, and the response obtained from CMCPE is 2 and 3 times of that from the Pb and graphite electrode, respectively. Results also display that the lifetime and the stability of the CMCPE is superior to that of L-cysteine ornamented graphite electrode fabricated by covalently bonding. Under the optimal conditions, a low concentration limit of detection 0.065µgL-1 of Se(IV) is achieved. The repeatability denoted as % RSD is 2.2% for 1.0µgL-1 Se(IV). The utility of the studied method is compared with certified reference materials as well as several edible samples. The advantages and limitations of this method, compared with existing techniques, are also discussed.


Assuntos
Carbono/química , Cisteína/química , Limite de Detecção , Oryza/química , Selênio/análise , Espectrometria de Fluorescência/instrumentação , Água/química , Eletrodos , Eletrólitos/química , Pomadas , Selênio/química , Propriedades de Superfície
4.
Talanta ; 165: 258-266, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-28153251

RESUMO

A novel non-chromatographic speciation technique for ultra-trace arsenite [As(III)] and total arsenic (tAs) in Chinese herbal medicine (CHM) is developed and validated by electrolytic hydride generation (EHG) coupled with atomic fluorescence spectrometry (AFS). The studies show that As(III) can be converted efficiently to AsH3 on an L-cysteine modified carbon paste electrode (CMCPE), which has never been reported before. Significantly, other arsenic species such as arsenate [As(V)], monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA) do not form any or only less volatile hydrides at low applied current mode (<1.0 A). The results also demonstrate that L-cysteine and graphite powder play different roles in the electrolytic generation of AsH3. Comparing with the traditional graphite electrode, CMCPE has better stability, sensitivity and interference tolerance. Under the optimal conditions, the limit of detection (LOD) of tAs and As(III) for this method are 0.087µgL-1 and 0.095µgL-1 respectively. The accuracy of the method is verified through the analysis of reference materials (CRM 08231 and SRM1568a), and the proposed method has been applied satisfactorily to the determination of As(III) and tAs in several CHM samples.


Assuntos
Arsênio/análise , Arsenitos/análise , Carbono/química , Cisteína/química , Medicamentos de Ervas Chinesas/análise , Eletrodos , Espectrofotometria Atômica/métodos , Eletrólise , Limite de Detecção
5.
Sci Rep ; 6: 34182, 2016 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-27669995

RESUMO

Sexual glands are key sites affected by nanotoxicity, but there is no sensitive assay for measuring reproductive toxicity in animals. The aim of this study was to investigate the toxic effects of cadmium telluride quantum dots (CdTe-QDs) on gonads in a model organism, Bombyx mori. After dorsal vein injection of 0.32 nmol of CdTe-QDs per individual, the QDs passed through the outer membranes of gonads via the generation of ROS in the membranes of spermatocysts and ovarioles, as well as internal germ cells, thereby inducing early germ cell death or malformations via complex mechanisms related to apoptosis and autophagy through mitochondrial and lysosomal pathways. Histological observations of the gonads and quantitative analyses of germ cell development showed that the reproductive toxicity was characterized by obvious male sensitivity. Exposure to QDs in the early stage of males had severe adverse effects on the quantity and quality of sperm, which was the main reason for the occurrence of unfertilized eggs. Ala- or Gly-conjugated QDs could reduce the nanotoxicity of CdTe-QDs during germ cell development and fertilization of their offspring. The results demonstrate that males are preferable models for evaluating the reproductive toxicity of QDs in combined in vivo/in vitro investigations.

6.
Talanta ; 159: 127-136, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27474289

RESUMO

This work describes a novel non-chromatographic approach for the accurate and selective determining As species by modified graphite electrode-based electrolytic hydride generation (EHG) for sample introduction coupled with atomic fluorescence spectrometry (AFS) detection. Two kinds of sulfydryl-containing modifiers, l-cysteine (Cys) and glutathione (GSH), are used to modify cathode. The EHG performance of As has been changed greatly at the modified cathode, which has never been reported. Arsenite [As(III)] on the GSH modified graphite electrode (GSH/GE)-based EHG can be selectively and quantitatively converted to AsH3 at applied current of 0.4A. As(III) and arsenate [As(V)] on the Cys modified graphite electrode (Cys/GE) EHG can be selectively and efficiently converted to arsine at applied current of 0.6A, whereas monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA) do not form any or only less volatile hydrides under this condition. By changing the analytical conditions, we also have achieved the analysis of total As (tAs) and DMA. Under the optimal condition, the detection limits (3s) of As(III), iAs and tAs in aqueous solutions are 0.25µgL(-1), 0.22µgL(-1) and 0.10µgL(-1), respectively. The accuracy of the method is verified through the analysis of standard reference materials (SRM 1568a).


Assuntos
Arsênio/análise , Técnicas de Química Analítica/métodos , Eletrodos , Grafite/química , Oryza/química , Espectrometria de Fluorescência , Água/química , Arsênio/química , Técnicas de Química Analítica/instrumentação
7.
Zhongguo Dang Dai Er Ke Za Zhi ; 11(5): 346-8, 2009 May.
Artigo em Chinês | MEDLINE | ID: mdl-19470253

RESUMO

OBJECTIVE: To investigate the clinical significance of serum Cyst-C and urinary microalbumin in early renal impairment in children with Henoch-Schonlein purpura (HSP). METHODS: Forty-eight children with HSP and who had normal serum creatinine level and 31 healthy children were enrolled. Contents of serum Cyst-C and urinary microalbumin were measured using ELISA and immunoturbidimetry, respectively. Urinary routine examination was performed in children with HSP. The contents of serum Cyst-C and urinary microalbumin were re-examined one month after treatment (recovery phase). RESULTS: The contents of serum Cyst-C (2.24+/- 0.81 mg/L) and urinary microalbumin (20.04+/- 10.32 mg/L) in the HSP group at the acute phase were significantly higher than those in the control (0.85+/- 0.20 and 2.30+/- 1.38 mg/L respectively; P< 0.01). Serum Cyst-C (1.70+/- 0.30 mg/L) and urinary microalbumin contents (13.20+/- 8.16 mg/L) were significantly reduced at the recovery phase compared with those at the acute phase in the HSP group (P< 0.01). The proportion of urinary routine abnormality (33.3%) was significantly lower than that of urinary microalbumin (68.8%) and serum Cyst-C abnormalities (72.9%) in the HSP group (P< 0.01). CONCLUSIONS: Serum Cyst-C and urinary microalbumin may serve as indexes in the assessment of early renal impairment in children with HSP.


Assuntos
Albuminúria/etiologia , Cistatina C/sangue , Vasculite por IgA/complicações , Adolescente , Criança , Pré-Escolar , Creatina/sangue , Feminino , Taxa de Filtração Glomerular , Humanos , Vasculite por IgA/sangue , Vasculite por IgA/urina , Nefropatias/diagnóstico , Nefropatias/etiologia , Masculino
8.
Huan Jing Ke Xue ; 29(6): 1502-7, 2008 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-18763491

RESUMO

The kinetic rules of degradation were studied in ultrasonic airlift loop reactor (UALR) in which O3 was introduced as oxidant and the organophosphorus pesticide dimethoate was used as typical contaminant. It was found that the dimethoate degradations under the individual ultrasonic radiation treatment without O3 (US), the oxidation of O3 gas (O3) and the synergetic effect of UALR and O3 (UALR/O3) were all consonant with the apparent first-order reaction by the kinetics investigations. The dimethoate removal rates of US, O3 and UALR/O3 methodologies under the conditions of dimethoate initial concentration of 50 mg/L, initial solution pH of 6.0, dimethoate solution volume of 80 mL, ultrasonic intensity of 0.5 W/cm2, O3 flow of 200 L/h, temperature of 20 degrees C and the treatment time of 4 h were 27%, 15% and 90%, respectively. Under these conditions, the rate constant enhancement factor of dimethoate degradation reached 4.816. Furthermore, a simplified mechanistic kinetic model was derived from the degradation mechanism of the synergetic effect of US, O3 and hydroxyl free radical (*OH) in the UALR/O3 system.


Assuntos
Dimetoato/química , Ozônio/química , Ultrassom , Poluentes da Água/química , Reatores Biológicos , Fenômenos Químicos , Monitoramento Ambiental/instrumentação , Monitoramento Ambiental/métodos , Cinética , Oxirredução , Poluição da Água/prevenção & controle
9.
Sheng Wu Gong Cheng Xue Bao ; 19(6): 651-4, 2003 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-15971574

RESUMO

Chromosomal virulence genes acvB, abvA, chvA of Agrobacterium tumefaciens were cloned with the technique of transposon 5 insertion. The chromosome genes are necessary for Agrobacterium tumfaciens absorbing to cell ular surface of plant, the adherence reaction can't be executed and result in losing the toxicity if mutations are occurred in some chromosome genes. The chromosome toxicity gene is inactivated due to transposon Tn5 be inserted and the accept ant cell infected with Agrobacterium tumefaciens can't cause tumor ultimately. This article briefly introduces the research way of thinking and strategy of this technique and the important roles of every gene, which are taken of in the process of T-DNA's form, transfer, integration, and expression etc. This article also gives a presumption to T-DNA's transport: The plant cell wall's porin may be T-DNA's natural channel.


Assuntos
Agrobacterium tumefaciens/genética , Agrobacterium tumefaciens/patogenicidade , Virulência/genética , Agrobacterium tumefaciens/metabolismo , Elementos de DNA Transponíveis/genética , Elementos de DNA Transponíveis/fisiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA