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1.
Chemosphere ; 297: 134105, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35245590

RESUMO

Bacillus Thuringiensis (Bt) protein has a strong ability to complex with metal ions, which may increase the transport of metal ions in the soil multi-media system. In this study, the interactions between Cry1Ac protein and metal ions (Zn2+ and Cd2+) were investigated through spectroscopies and molecular docking methods. The spectra results showed that both Zn2+ and Cd2+ quenched the fluorescence intensity of Cry1Ac protein through the static quenching. The binding constants with 4-5 orders of magnitude also indicated the interactions between the ions and the Cry1Ac protein. The thermodynamic analysis showed that hydrogen bonds and van der Waals forces were predominant during the processes. In terms of the Förster non-radiation energy transfer theory, the binding distances between metal ions and Cry1Ac protein were approximately 0.21-0.24 nm, indicating the existence of a non-radiative energy transfer between them. Furthermore, molecular docking revealed that the metal ions participated in ligand binding with the Cry1Ac at the locations Asp569, Thr560, Asn564 and Gln566. The present work provided reasonable models helping us further understand the transport effect of heavy metals in the presence of Cry1Ac. The results could provide mechanistic insights into the nature of metal ions-Cry1Ac interactions and offer important information on the toxicity risk of metal ions-Cry1Ac binding interactions.


Assuntos
Cádmio , Metais , Sítios de Ligação , Íons , Metais/química , Simulação de Acoplamento Molecular , Ligação Proteica , Espectrometria de Fluorescência/métodos , Termodinâmica , Zinco
2.
Ecotoxicol Environ Saf ; 226: 112805, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34592526

RESUMO

During the production and application of Bacillus thuringiensis (Bt) transgenic crops, large doses of insecticidal Bt toxic proteins are expressed continuously. The multi-interfacial behaviors of Bt proteins entering the environment in multi-media affects their states of existence transformation, transport and fate as well as biological and ecological impacts. Because both soil matrix and organisms will be exposed to Bt proteins to a certain extent, knowledge of the multi-interfacial behaviors and affecting factors of Bt proteins are vital not only for understanding the source-sink distribution mechanisms, predicting their bio-availability, but also for exploring the soil safety and environmental problems caused by the interaction between Bt proteins and soil matrix. This review summarized and analyzed various internal and external factors that affect the adsorption/ desorption and degradation of Bt proteins in the environment, so as to understand the multi-interfacial behaviors of Bt proteins. In addition, the reasons of concentration changes of Bt proteins in soil are discussed. This review will also discuss the existing knowledge of the combined effects of Bt proteins and other pollutants in environment. Finally, discussing the factors that should be considered when assessing the environmental risk of Bt proteins, thus to further improve the understanding of the environmental fate of Bt proteins.


Assuntos
Bacillus thuringiensis , Adsorção , Bacillus thuringiensis/genética , Proteínas de Bactérias/genética , Endotoxinas , Proteínas Hemolisinas/genética , Plantas Geneticamente Modificadas , Solo
3.
Medicine (Baltimore) ; 99(25): e20679, 2020 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-32569198

RESUMO

The aim of this study was to quantify changes in the lateral ventricular volume, the depth of the calcarine sulcus (CS), and apparent diffusion coefficient (ADC) values of occipital lobe in fetuses with isolated mild ventriculomegaly (IMVM) using MRI.Seventy-one fetuses with IMVM at 25 to 38 weeks gestational age (GA) and 58 fetuses with normal lateral ventricles at 25 to 38 weeks GA were enrolled. Volumes of the lateral ventricles were measured by 3D magnetic resonance hydrography. Depths of the CS and ADC values were also evaluated. All differences were tested by t test. Bivariate correlations were performed using Pearson method.Fetuses with IMVM had significantly larger lateral ventricular volumes and smaller CS depths than controls (volumes: 9.37 ±â€Š2.20 mL vs 5.04 ±â€Š1.33 mL, respectively, P < .001; depths: 8.27 ±â€Š2.55 mm vs 10.30 ±â€Š3.14 mm, respectively, P < .001). In IMVM cases, the CS depths were smaller on the side with the larger ventricle (8.10 ±â€Š2.54 mm vs 9.59 ±â€Š2.81 mm, P < .001). No differences were observed in occipital lobe ADC values between the2 groups (IMVM = 1.80 ±â€Š0.24 µm/ms; controls = 1.78 ±â€Š0.28 µm/ms, P > .05).Fetuses with IMVM had larger lateral ventricular volumes, shallower CS depths, but normal occipital lobe ADC values.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Feto/diagnóstico por imagem , Hidrocefalia/diagnóstico por imagem , Ventrículos Laterais/diagnóstico por imagem , Lobo Occipital/diagnóstico por imagem , Diagnóstico Pré-Natal/métodos , Feminino , Idade Gestacional , Humanos , Imageamento Tridimensional , Gravidez , Reprodutibilidade dos Testes
4.
Medicine (Baltimore) ; 98(26): e16118, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31261528

RESUMO

To explore the growth trend of fetal lateral ventricular volume, for understanding the relationship between atrial diameter (AD) and volume in normal fetus and fetus with ventriculomegaly.Overall, 97 sequential fetal head magnetic resonance imaging scans were performed; these pertained to 50 fetuses with normal lateral ventricles [normal group; gestational age (GA): 24-38 weeks] and 47 fetuses with ventriculomegaly (VM) (VM group; GA: 24-37 weeks). The left, right, and total lateral ventricular volume were measured using 3-dimensional magnetic resonance hydrography (MRH). Correlation coefficient (r) was calculated to assess the relationships of measurements. Lineal regression analysis was used to assess correlation of AD and GA with volume. Between-group differences in terms of AD and volume were assessed using t test.Significant linear growth was observed in the total lateral ventricular volume compared with GA in the normal group with a relative growth rate of 2.87% per week (P <.001). Significant linear relationship between AD and volume was observed, and a significant equation was acquired in the normal group and VM groups, respectively, using the simple linear regression model: left volume = 0.438 * normal left diameter (NLD) + 1.359; right volume = 0.493 * normal right diameter (NRD) + 1.012; left volume = 0.959 * left diameter in VM (VLD) - 2.074; right volume = 0.799 * right diameter in VM (VRD) - 0.443. A significant equation was obtained in the normal group and the VM group, using the multiple linear regression model: Total volume (mL) = 0.396 * NLD + 0.410 * NRD + 3.101; and total volume = 0.989 * VLD + 0.834 * VRD - 3.141, respectively. In terms of AD and volume, the left lateral ventricle was significantly larger than the right side in both groups. The volume of lateral ventricle in AD ≥10 mm group was larger than that in the AD <10 mm group. The total volume in the VM group was significantly larger than that in the normal group.The total lateral ventricular volume increased with GA. AD can be used to evaluate the fetal ventricular volume.


Assuntos
Hidrocefalia/diagnóstico por imagem , Hidrocefalia/embriologia , Ventrículos Laterais/diagnóstico por imagem , Ventrículos Laterais/embriologia , Feminino , Humanos , Hidrocefalia/patologia , Ventrículos Laterais/patologia , Imageamento por Ressonância Magnética , Tamanho do Órgão , Gravidez , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez , Diagnóstico Pré-Natal , Estudos Prospectivos
5.
J Magn Reson Imaging ; 48(1): 266-273, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29251798

RESUMO

BACKGROUND: In fetuses with prenatal ventriculomegaly (VM), ventricular volume on MRI has been shown to correlate with poor postnatal outcomes and in utero death. 3D magnetic resonance hydrography (MRH) has been widely used for MR cholangiopancreatography. PURPOSE: To investigate the reliability of 3D MRH for lateral ventricular volume measurement in fetuses with VM and normal lateral ventricles, using manual multisection planimetry (MSP) as a reference standard. STUDY TYPE: Prospective study. POPULATION: Thirty-five fetuses with VM at 24-37 gestational weeks (GA) and 35 fetuses with normal lateral ventricles at 24-38 GA. FIELD STRENGTH/SEQUENCE: 1.5T MRI with 3D MRH and T2 -weighted single-shot fast-spin echo sequence. ASSESSMENT: Left, right, and total lateral ventricle volumes in fetuses were acquired from 3D MRH and manual MSP. All image analysis was performed by a radiologist twice and another radiologist once, blindly. STATISTICAL TESTS: Analysis of linear regression analysis, Pearson's correlation coefficient, Bland-Altman plots, intraclass correlation coefficient (ICC), and independent samples t-test were used for statistical analyses. RESULTS: There were highly significant relationships between all 3D MRH and manual MSP measurements of lateral ventricular volumes (rVM = 0.92-0.98; rN = 0.95-0.98; all P < 0.0001; VM: VM group, N: normal group), although left, right, and total lateral ventricular volumes measured by 3D MRH tended to be slightly larger than MSP (biasVM 0.1 ± 0.95, 0.26 ± 0.63, and 0.3 ± 0.68 mL, respectively; biasN 0.1 ± 0.95, 0.26 ± 0.63, and 0.3 ± 0.68 mL, respectively). Interrater agreement and intrarater repeatability were also excellent for 3D MRH (ICCVM = 0.994-0.99, ICCN = 0.989-0.992; ICCVM = 0.975-0.987, ICCN = 0.958-0.971, respectively). 3D MRH showed significantly reduced measurement time (VM: 3.55 ± 0.42 vs. 11.81 ± 0.13 min; N: 3.08 ± 0.39 vs. 12.12 ± 0.11 min; all P < 0.0001). DATA CONCLUSION: Lateral ventricular volume measurement by 3D MRH was comparable to manual MSP. LEVEL OF EVIDENCE: 1 Technical Efficacy Stage 1 J. Magn. Reson. Imaging 2017.


Assuntos
Colangiopancreatografia por Ressonância Magnética , Imageamento por Ressonância Magnética , Neoplasias da Bexiga Urinária/diagnóstico por imagem , Feminino , Idade Gestacional , Humanos , Hidrocefalia/diagnóstico por imagem , Imageamento Tridimensional , Inflamação , Ventrículos Laterais/diagnóstico por imagem , Modelos Lineares , Variações Dependentes do Observador , Gravidez , Diagnóstico Pré-Natal/métodos , Estudos Prospectivos , Padrões de Referência , Reprodutibilidade dos Testes
6.
Optom Vis Sci ; 94(6): 707-713, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28514246

RESUMO

PURPOSE: The Intermittent Exotropia Questionnaire (IXTQ) is a child, proxy, and parent report of health-related quality of life specific to children with intermittent exotropia (IXT). The present study aimed to develop a Chinese-language version of the IXTQ (CIXTQ) and evaluate its validity and reliability when used in Chinese IXT children and their parents. METHODS: The IXTQ was translated into Chinese. One hundred seventy-five IXT children (2 to 17 years old) and 151 orthotropic control children (2 to 17 years old) along with one of their parents were recruited. Children 5 to 17 years old completed the 5- to 7-year-old or the 8- to 17-year-old child questionnaire of the CIXTQ according to their age. Parents of all children (2 to 17 years old) completed the proxy and parent questionnaires of the CIXTQ. Psychometric properties of the CIXTQ were examined for floor and ceiling effects, construct validity, item-internal consistency, discriminative validity, Cronbach α coefficient and test-retest reliability. RESULTS: No items were found to have strong floor or ceiling effects. Principal component analysis identified that the CIXTQ had a similar structure to the original English version. The median scores of each questionnaire in the CIXTQ among children with IXT and their parents were significantly lower than those among control subjects (P < .001). Cronbach α coefficients ranged from 0.869 to 0.931, and test-retest reliabilities ranged from 0.898 to 0.981, for each questionnaire in the CIXTQ. CONCLUSIONS: The CIXTQ is a useful tool to evaluate the influence of IXT on health-related quality of life among Chinese IXT children and their parents.


Assuntos
Exotropia/diagnóstico , Nível de Saúde , Psicometria/métodos , Qualidade de Vida , Inquéritos e Questionários , Adolescente , Criança , Pré-Escolar , China , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Perfil de Impacto da Doença
7.
Dev Cogn Neurosci ; 19: 137-43, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26999477

RESUMO

Caudate nucleus volume is enlarged in autism spectrum disorder (ASD) and is associated with restricted and repetitive behaviors (RRBs). However, the trajectory of caudate nucleus volume in RRBs of young children remains unclear. Caudate nucleus volume was measured in 36 children with ASD and 18 matched 2-3-year-old subjects with developmentally delayed (DD) at baseline (Time 1) and at 2-year follow-up (Time 2). The differential growth rate in caudate nucleus volume was calculated. Further, the relationships between the development of caudate nucleus volume and RRBs were analyzed. Our results showed that caudate nucleus volume was significantly larger in the ASD group at both time points and the magnitude of enlargement was greater at Time 2. The rate of caudate nucleus growth during this 2-year interval was faster in children with ASD than DD. Right caudate nucleus volume growth was negatively correlated with RRBs. Findings from this study suggest developmental abnormalities of caudate nucleus volume in ASD. Longitudinal MRI studies are needed to explore the correlation between atypical growth patterns of caudate nucleus and phenotype of RRBs.


Assuntos
Transtorno do Espectro Autista/diagnóstico por imagem , Transtorno do Espectro Autista/fisiopatologia , Núcleo Caudado/diagnóstico por imagem , Núcleo Caudado/fisiopatologia , Deficiências do Desenvolvimento/diagnóstico por imagem , Deficiências do Desenvolvimento/fisiopatologia , Fatores Etários , Núcleo Caudado/crescimento & desenvolvimento , Pré-Escolar , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética/tendências , Masculino
8.
Zhongguo Zhong Yao Za Zhi ; 38(17): 2755-60, 2013 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-24380293

RESUMO

OBJECTIVE: In order to provide theoretical basis of improving nitrogen utilization efficiency in Isatis indigotica, the biomass and active components in Isatidis Folium under different nitrogen forms and concentrations were analyzed. METHOD: I. indigotica was cultivated by sand culture in greenhouse, and the experiment was designed with orthogonal test L25 (5(6)). As an index to the biomass and indigo, indirubin, the effects on the I. indigotica by three factors [NO3(-) -N, NH4(+) -N, CO(NH2)2] at five different levels were studied. RESULT: There were significant difference of the biomass and active components by different nitrogen forms and concentrations. The effect of amide nitrogen [CO(NH2)2] on biomass of Isatidis Folium was the most apparent, and the effect of ammonium nitrogen on indirubin was more obvious. Considering the biomass and active ingredient, one combination was optimized, which was (NH4)2SO(4)-7.5 mmol x L(-1), KNO(3)-2.5 mmol x L(-1), CO(NH2)(2)- 5 mmol x L(-1). CONCLUSION: It is important to promote the growth in pre-stage of I. indigotica, and cost-effective combination of balanced nitrogen fertilizer could reasonably promote the growth, and improve the contents of active components and individual biomass.


Assuntos
Alcaloides/análise , Medicamentos de Ervas Chinesas/análise , Isatis/química , Isatis/crescimento & desenvolvimento , Nitrogênio/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Alcaloides/metabolismo , Biomassa , Medicamentos de Ervas Chinesas/metabolismo , Isatis/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo
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