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1.
Langmuir ; 39(14): 5199-5210, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-36975611

RESUMO

Molecular simulation has been used extensively in the study of pervaporation membranes as a new economical and environmentally friendly research method. In this paper, A-SiO2/PDMS-PTFE mixed matrix membranes (MMMs) were prepared by molecular-simulation-guided experiments to achieve the separation of dimethyl carbonate/methanol (DMC/MeOH)) azeotropes. The interaction energy, X-ray diffraction pattern mean square displacement, and density field between PDMS and inorganic particles were analyzed by molecular dynamics simulations. The dissolution and diffusion processes of the DMC/MeOH azeotropes system in the MMM were simulated, and the surface-silylated silica (A-SiO2) with relatively better performance was screened. Based on the simulation results, A-SiO2/PDMS-PTFE MMMs were prepared by the coblending method, and the pervaporation separation performance of MMM membranes for DMC/MeOH azeotropes with different A-SiO2 loadings was investigated. When the A-SiO2 loading was 15 wt %, the separation factor of DMC/MeOH azeotropes at 50 °C was 4.74 and the flux was 1178 g m-2 h-1, which was consistent with the expected results of the simulation. The MMMs showed good stability in pervaporation over a period of up to 120 h. This study demonstrates that molecular simulations can provide a viable means for pretest screening and validation of experimental mechanisms, and to a certain extent, guide the design and optimization of pervaporation membranes.

2.
Int J Mol Sci ; 23(21)2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36361801

RESUMO

In this work, we propose the idea of considering (∂p∂x)T, x→0 as an infinite dilution thermodynamic function. Our research shows that (∂p∂x)T,x→0 as a thermodynamic function is closely related to temperature, with the relation being simply expressed as: ln(∂p∂x)T, x→0=AT+B. Then, we use this equation to correlate the isothermal vapor−liquid equilibrium (VLE) data for 40 systems. The result shows that the total average relative deviation is 0.15%, and the total average absolute deviation is 3.12%. It indicates that the model correlates well with the experimental data. Moreover, we start from the total pressure expression, and use the Gibbs−Duhem equation to re-derive the relationship between (∂p∂x)T,x→0 and the infinite dilution activity coefficient (γ∞) at low pressure. Based on the definition of partial molar volume, an equation for (∂p∂x)T,x→0 and gas solubility at high pressure is proposed in our work. Then, we use this equation to correlate the literature data on the solubility of nitrogen, hydrogen, methane, and carbon dioxide in water. These systems are reported at temperatures ranging from 273.15 K to 398.15 K and pressures up to 101.325 MPa. The total average relative deviation of the predicted values with respect to the experimental data is 0.08%, and the total average absolute deviation is 2.68%. Compared with the Krichevsky−Kasarnovsky equation, the developed model provides more reliable results.


Assuntos
Gases , Água , Temperatura , Termodinâmica , Solubilidade
3.
Small ; 13(23)2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28452180

RESUMO

Polymer nanocomposite (NC) hydrogels, with 3D networks composed of delaminated inorganic nanoparticles and a polymer matrix, usually display super mechanical toughness. However, the few types of inorganic materials and relatively scarce research for NC hydrogel functions seriously limit their applications. For the first time layered rare-earth hydroxide (LRH)/polyacrylamide NC hydrogels with highly tunable photoluminescence (PL) function are reported, prepared via a convenient and green in situ polymerization process. Interestingly, the NC hydrogels reveal exciting multicolored PL phenomenon (green, yellow, orange, reddish-orange to bluish violet), long luminescence lifetime, and relatively high quantum efficiency. Furthermore, the fascinating PL function is highly tunable by adjusting LRH constituent or its concentration, and excitation wavelength. The results highlight the fabrication and applications of functional polymer NC hydrogels with highly tunable PL function.

4.
Soft Matter ; 11(46): 9038-44, 2015 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-26412191

RESUMO

A convenient green preparation method has been developed to achieve layered double hydroxide (LDH)/polymer nanocomposite (NC) hydrogels. In contrast to previous publications using toxic organic solvent of formamide or methanol in LDH exfoliation or anion exchange, the interlayer anion exchange and exfoliation of LDH are completed in one step with the help of an amino acid (L-serine). The LDH/polyacrylamide (PAM) NC hydrogels are achieved by a convenient exfoliation-adsorption in situ polymerization method. The exfoliation of LDH is characterized by dynamic light scattering and transmission electron microscopy. Interestingly, the developed NC hydrogels reveal ultrahigh deformability and extraordinary stretchability, confirmed by qualitative images and qualitative tensile and compression tests. The molecular mechanism for the ultrahigh deformability and extraordinary stretchability is discussed by crosslinking density, inter-crosslinking molecular weight and swelling tests. We believe that the findings reported herein will deepen our understanding towards the chemistry of network soft materials including gels, and further widen the applications of polymer hydrogels in mechanical devices such as artificial muscles, biomedical devices and drug delivery systems.

5.
Heliyon ; 10(9): e30438, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38765101

RESUMO

Neurodegeneration with brain iron accumulation (NBIA) is a clinically and genetically heterogeneous disease characterized by increased iron deposition in the basal ganglia and progressive degeneration of the nervous system in adulthood. However, in early childhood, there were no characteristic features to perform early diagnosis. In our study, a female child exhibited global developmental delay, intellectual disability, and febrile seizure without other distinct clinical phenotypes. Through whole exome sequencing (WES), a de novo nonsense mutation (c.726C > G, p. Tyr242Ter) of WDR45 gene was identified in this child. She was finally diagnosed as ß-propeller protein-associated neurodegeneration (BPAN), one of the recently identified subtypes of NBIA. This mutation could act as a premature stop codon (PSC) which rendered the mutated transcripts to be degraded by nonsense-mediated mRNA decay (NMD), leading to decreased levels of PSC-containing mRNAs. Additionally, through mini-gene splicing assays, this mutation could result in an unprecedented novel transcript with the exon 9 of WDR45 excluded by nonsense-associated splicing alteration (NASA). Transcriptome sequencing (RNA-seq) on total RNAs from PBMCs of the trio revealed three types of alternative splicing events in the patient. Further research implied that downregulation of iron transport genes (TFRC, TFR2, SCARA5) might be the underlying mechanism for the iron accumulation in patients with deficient WDR45. This is the first report about NASA happening in WDR45. It implies that nonsense mutations approximal to splicing sites could affect the disease pathogenesis through more than one molecular mechanism and should be taken into consideration when conducting genetic counseling.

6.
ACS Omega ; 8(13): 12439-12444, 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37033839

RESUMO

Accurate prediction of infinite dilution activity coefficient (γ∞) is essential for the calculation of phase equilibria, solubility, and related properties in molecular thermodynamics. Here, we propose a new model to accurately predict the value of γ∞. It is applicable to calculate γ∞ for compounds in aqueous solution at different temperatures. The model is based on the relationship of (∂p/∂x) T,x→0 with γ∞ and temperature at low pressure. First, we introduce the new idea of using the group contribution method to estimate (∂p/∂x) T,x→0 and then obtain the activity coefficient of a solute at infinite dilution in water based on the relationship between (∂p/∂x) T,x→0 and γ∞. The accuracy of this model is verified using experimental data from 46 systems and more than 450 data points. The result shows that the total average relative deviation of the predicted values from the experimental values for training data is 4.73%. Besides, we test the applicability of the model using solutes that are not part of the training data set. The result shows that the model is satisfactory for the prediction of testing data. Compared with other models, the results prove that the developed model outperforms the UNIFAC model, the modified UNIFAC model, and previous predictive models for aqueous systems. The final equation with only simple arithmetic is more easily applied in engineering practices.

7.
ACS Omega ; 8(25): 22536-22544, 2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37396225

RESUMO

The establishment of mathematical models to predict the diffusion coefficients of gas and liquid systems have important theoretical significance and practical value. In this work, based on the previously proposed diffusion coefficient model DLV, the distribution and influencing factors of the model parameters characteristic length (L) and diffusion velocity (V) were further investigated using molecular dynamics simulations. The statistical analysis of L and V for 10 gas systems and 10 liquid systems was presented in the paper. New distribution functions were established to describe the probability distributions of molecular motion L and V. The mean values of the correlation coefficients were 0.98 and 0.99, respectively. Meanwhile, the effects of molecular molar mass and system temperature on the molecular diffusion coefficients were discussed. The results show that the effect of molecular molar mass on the diffusion coefficient mainly affects the molecular motion L, and the effect of system temperature on the diffusion coefficient mainly affects V. For the gas system, the average relative deviation of DLV and DMSD is 10.73% and that of DLV and experimental value is 12.63%; for the solution system, the average relative deviation of DLV and DMSD is 12.93% and that of DLV and experimental value is 18.86%, which indicates the accuracy of the new model results. The new model reveals the potential mechanism of molecular motion and provides a theoretical basis for further study of the diffusion process.

8.
Biochim Biophys Acta ; 1810(8): 784-9, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21571040

RESUMO

BACKGROUND: Constituents and inhibitors of intermediary metabolism resulting in alterations in levels of cytosolic NADH, stimulation of sphingomyelinase and inhibition of sphingosine kinase were evaluated for effects on growth inhibition and induction of apoptosis by the ENOX2 inhibitors EGCG, the principal catechin of green tea, and phenoxodiol, a naturally occurring isoflavone. METHODS: Responses were evaluated from dose-response curves of the metabolites and metabolic inhibitors in which growth of HeLa cells, apoptosis based on DAPI fluorescence and cytosolic NADH levels were correlated with sphingomyelinase and spingosine kinase activities and levels of ceramide and sphingosine1-phosphate. RESULTS: Growth inhibition correlated with the modulation of localized cytosolic NADH levels by metabolites and metabolic inhibitors, the response of sphingomyelinase and sphingosine kinase located near the inner surface of the plasma membrane, and apoptosis. CONCLUSIONS: Based on findings with metabolites, we conclude that apoptosis in cancer cell lines caused by ENOX2 inhibitors such as EGCG and phenoxodiol is a direct response to elevated levels of cytosolic NADH that result from ENOX2 inhibition. GENERAL SIGNIFICANCE: The findings help to explain why increased NADH levels resulting from ENOX2 inhibition result in decreased prosurvival sphingosine-1-phosphate and increased proapoptotic ceramide, both of which may be important to initiation of the ENOX2 inhibitor-induced apoptotic cascade.


Assuntos
Apoptose/efeitos dos fármacos , Catequina/análogos & derivados , Inibidores Enzimáticos/farmacologia , Isoflavonas/farmacologia , NADH NADPH Oxirredutases/antagonistas & inibidores , NADH NADPH Oxirredutases/metabolismo , Anticarcinógenos/farmacologia , Catequina/farmacologia , Membrana Celular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células HeLa , Humanos , Lisofosfolipídeos/metabolismo , NADP/metabolismo , Esfingosina/análogos & derivados , Esfingosina/metabolismo
9.
Front Genet ; 13: 840577, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35432459

RESUMO

Background: Neurodevelopmental disorder with dysmorphic facies and distal skeletal anomalies (NEDDFSA) is a rare syndromic disorder characterized by global neurodevelopmental delay, early-onset hypotonia, poor overall growth, poor speech/language ability, and additional common phenotypes such as eye anomalies, joint hypermobility, and skeletal anomalies of the hands and feet. NEDDFSA is caused by heterozygous pathogenic variants in the ZMIZ1 gene on chromosome 10q22.3 with autosomal dominant (AD) mode of inheritance. All the 32 reported cases with variants in ZMIZ1 gene had a genetic background in Caucasian, Hispanic, North African, and Southeastern Asian. Until now, there are no reports of Chinese patients with ZMIZ1 pathogenic variants. Methods: A 5-year-old girl was found to have the characteristic phenotypes of NEDDFSA. Array-Comparative Genomic Hybridization (array-CGH) and whole exome sequencing (WES) were applied for the trio of this female patient. Sanger sequencing was used to verify the selected variants. A comprehensive molecular analysis was carried out by protein structure prediction, evolutionary conservation, motif scanning, tissue-specific expression, and protein interaction network to elucidate pathogenicity of the identified ZMIZ1 variants. Results: The karyotype was 46, XX with no micro-chromosomal abnormalities identified by array-CGH. There were 20 variants detected in the female patient by WES. A de novo heterozygous missense variant (c.2330G > A, p.Gly777Glu, G777E) was identified in the exon 20 of ZMIZ1. No variants of ZMIZ1 were identified in the non-consanguineous parents and her healthy elder sister. It was predicted that G777E was pathogenic and detrimental to the spatial conformation of the MIZ/SP-RING zinc finger domain of ZMIZ1. Conclusion: Thus far, only four scientific articles reported deleterious variants in ZMIZ1 and most of the cases were from Western countries. This is the first report about a Chinese patient with ZMIZ1 variant. It will broaden the current knowledge of ZMIZ1 variants and variable clinical presentations for clinicians and genetic counselors.

10.
Front Mol Neurosci ; 15: 1039990, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36568277

RESUMO

Background: FOXG1-related encephalopathy, also known as FOXG1 syndrome or FOXG1-related disorder, affects most aspects of development and causes microcephaly and brain malformations. This syndrome was previously considered to be the congenital variant of Rett syndrome. The abnormal function or expression of FOXG1, caused by intragenic mutations, microdeletions or microduplications, was considered to be crucial pathological factor for this disorder. Currently, most of the FOXG1-related encephalopathies have been identified in Europeans and North Americans, and relatively few Chinese cases were reported. Methods: Array-Comparative Genomic Hybridization (Array-CGH) and whole-exome sequencing (WES) were carried out for the proband and her parent to detect pathogenic variants. Results: A de novo nonsense mutation (c.385G>T, p.Glu129Ter) of FOXG1 was identified in a female child in a cohort of 73 Chinese children with neurodevelopmental disorders/intellectual disorders (NDDs/IDs). In order to have a comprehensive view of FOXG1-related encephalopathy in China, relevant published reports were browsed and twelve cases with mutations in FOXG1 or copy number variants (CNVs) involving FOXG1 gene were involved in the analysis eventually. Feeding difficulties, seizures, delayed speech, corpus callosum hypoplasia and underdevelopment of frontal and temporal lobes occurred in almost all cases. Out of the 12 cases, eight patients (66.67%) had single-nucleotide mutations of FOXG1 gene and four patients (33.33%) had CNVs involving FOXG1 (3 microdeletions and 1 microduplication). The expression of FOXG1 could also be potentially disturbed by deletions of several brain-active regulatory elements located in intergenic FOXG1-PRKD1 region. Further analysis indicated that PRKD1 might be a cooperating factor to regulate the expression of FOXG1, MECP2 and CDKL5 to contribute the RTT/RTT-like disorders. Discussion: This re-analysis would broaden the existed knowledge about the molecular etiology and be helpful for diagnosis, treatment, and gene therapy of FOXG1-related disorders in the future.

11.
Front Mol Neurosci ; 15: 1026530, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36385762

RESUMO

Wiedemann-Rautenstrauch syndrome (WDRTS) is an extremely rare autosomal recessive neonatal disorder. Currently, over 50 cases with variable phenotypes of WDRTS have been reported. In our cohort of prenatal and postnatal growth retardation, a female proband was found to have general growth retardation, neurocutaneous syndrome, and anemia. Karyotype test and array-CGH detected no obvious chromosomal aberrations. Trio-based whole-exome sequencing (Trio-WES) identified bi-allelic compound mutations in the coding sequence (CDS) of POLR3A gene (c.3342C > T, p.Ser1114 = and c.3718G > A, p.Gly1240Ser). For the mild anemia phenotype, the underlying causal genetic factors could be attributed to the compound heterozygous mutations in FANCA gene (c.2832dup, p.Ala945CysfsTer6 and c.1902 T > G, p.Asp634Glu). Mini-gene reporter assays revealed that the synonymous variant of POLR3A and the missense variant of FANCA could affect pre-mRNA splicing of each gene. For POLR3A, the synonymous mutation (c.3342C > T, p.Ser1114=) generated three types of aberrant isoforms. Therefore, the female patient was finally diagnosed as WDRTS caused by POLR3A. For FANCA, the missense variant (c.1902 T > G, p.Asp634Glu) disrupted the normal splicing between exon 21 and 22, and produced two types of abnormal isoforms, one carrying the 1902G and the other spliced between exon 21 and 23 to exclude exon 22. Network analysis showed that POLR3A and FANCA could be STRINGed, indicating both proteins might collaborate for some unknown functions. Current investigation would broaden the knowledge for clinicians and genetic counselors and remind them to interpret those synonymous or predicted "benign" variants more carefully.

12.
BMC Med Genomics ; 14(1): 270, 2021 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-34775996

RESUMO

BACKGROUND: Coffin-Siris syndrome (CSS) is a multiple malformation syndrome characterized by intellectual disability associated with coarse facial features, hirsutism, sparse scalp hair, and hypoplastic or absent fifth fingernails or toenails. CSS represents a small group of intellectual disability, and could be caused by at least twelve genes. The genetic background is quite heterogenous, making it difficult for clinicians and genetic consultors to pinpoint the exact disease types. METHODS: Array-Comparative Genomic Hybridization (array-CGH) and whole exome sequencing (WES) were applied for three trios affected with intellectual disability and clinical features similar with those of Coffin-Siris syndrome. Sanger sequencing was used to verify the detected single-nucleotide variants (SNVs). RESULTS: All of the three cases were female with normal karyotypes of 46, XX, born of healthy, non-consanguineous parents. A 6q25 microdeletion (arr[hg19]6q25.3(155,966,487-158,803,979) × 1) (2.84 Mb) (case 1) and two loss-of-function (LoF) mutations of ARID1B [c.2332 + 1G > A in case 2 and c.4741C > T (p.Q1581X) in case 3] were identified. All of the three pathogenic abnormalities were de novo, not inherited from their parents. After comparison of publicly available microdeletions containing ARID1B, four types of microdeletions leading to insufficient production of ARID1B were identified, namely deletions covering the whole region of ARID1B, deletions covering the promoter region, deletions covering the termination region or deletions covering enhancer regions. CONCLUSION: Here we identified de novo ARID1B mutations in three Chinese trios. Four types of microdeletions covering ARID1B were identified. This study broadens current knowledge of ARID1B mutations for clinicians and genetic consultors.


Assuntos
Anormalidades Múltiplas/genética , Hibridização Genômica Comparativa/métodos , Proteínas de Ligação a DNA/genética , Sequenciamento do Exoma/métodos , Face/anormalidades , Deformidades Congênitas da Mão/genética , Haploinsuficiência/genética , Deficiência Intelectual/genética , Micrognatismo/genética , Pescoço/anormalidades , Mutação Puntual , Deleção de Sequência , Fatores de Transcrição/genética , Cromossomos Humanos Par 6 , Feminino , Humanos , Lactente , Recém-Nascido , Polimorfismo de Nucleotídeo Único
13.
Mucosal Immunol ; 14(1): 152-163, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32203063

RESUMO

Extra-intestinal manifestations (EIMs) of the eyes are found in IBD patients, but the underlying pathogenesis remains unknown. To investigate the pathogenesis of IBD-associated retinal dysfunction, chronic colitis was induced in mice by oral administration of dextran sodium sulfate (DSS). Electroretinography (ERG) was performed to evaluate retinal function. Retinal neuron degeneration was analyzed by immunohistochemistry. Colitic mice displayed aberrant amplitudes of ERG a-, b-wave and oscillatory potentials (OP). Importantly, we observed severe degeneration of bipolar and ganglion cells. In contrast, outer retinal neurons (mainly photoreceptor cells) are mildly affected by colitis. Moreover, retinal inflammatory responses were significantly upregulated during colitis, including microglia activation, lymphocyte infiltration and cytokine/chemokine production. Notably, mucosal addressin cell adhesion molecule 1 (MAdCAM-1) was upregulated in retinal microvessels, especially the superficial and deep plexuses, and recruited gut-homing CD4+ T cells to be co-localized with bipolar and ganglion cells during colitis. Expectedly, in vivo depletion of CD4+ T cells or blockade of MAdCAM-1 greatly alleviated colitis-induced retinal inflammatory responses and neuron degeneration. Therefore, our data provide novel insight into the pathogenesis of IBD-associated retinal dysfunction, and targeted immune therapy directly against MAdCAM-1 might provide a novel approach in the management of eye EIM of IBD.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Moléculas de Adesão Celular/genética , Colite/complicações , Colite/imunologia , Mucoproteínas/genética , Degeneração Neural/etiologia , Neurônios Retinianos/metabolismo , Animais , Biomarcadores , Moléculas de Adesão Celular/metabolismo , Colite/etiologia , Colite/patologia , Citocinas/metabolismo , Modelos Animais de Doenças , Suscetibilidade a Doenças , Mediadores da Inflamação/metabolismo , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Camundongos , Mucoproteínas/metabolismo , Degeneração Neural/diagnóstico , Degeneração Neural/metabolismo , Neurônios Retinianos/patologia
14.
Polymers (Basel) ; 12(7)2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32629862

RESUMO

Membrane separation technologies have attracted great attentions in chemical engineering, food science, analytical science, and environmental science. Compared to traditional membrane separation techniques like reverse osmosis (RO), ultrafiltration (UF), electrodialysis (ED) and others, pervaporation (PV)-based membrane separation shows not only mutual advantages such as small floor area, simplicity, and flexibility, but also unique characteristics including low cost as well as high energy and separation efficiency. Recently, different polymer, ceramic and composite membranes have shown promising separation applications through the PV-based techniques. To show the importance of PV for membrane separation applications, we present recent advances in the fabrication, properties and performances of polymeric membranes for PV separation of various chemicals in petrochemical, desalination, medicine, food, environmental protection, and other industrial fields. To promote the easy understanding of readers, the preparation methods and the PV separation mechanisms of various polymer membranes are introduced and discussed in detail. This work will be helpful for developing novel functional polymer-based membranes and facile techniques to promote the applications of PV techniques in different fields.

15.
ACS Omega ; 5(35): 22465-22474, 2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32923805

RESUMO

Studying the concentration and temperature dependence of the conductivity of electrolyte solution is of great significance for the evaluation and improvement of the performance of the electrochemical system. In this paper, based on the influence of the number of free ions and ion mobility on the conductivity, a semiempirical conductivity model with five parameters was proposed to correlate the conductivity, concentration and temperature data of electrolyte solutions at medium and high concentrations. The conductivities of NaCl and CaCl2 in propylene carbonate-H2O binary solvents were measured at temperatures varying from 283.15 to 333.15 K. The validity of the model was verified by the experimental data of this paper and the conductivity, concentration, and temperature data of 28 electrolyte solution systems in the literature. The electrolyte solutions investigated in this paper included binary organic solvent systems, pure organic solvent systems, and aqueous solution systems. The results showed that the proposed model can fit the experimental data well for both pure solvent and mixed solvents systems, which is of great value to practical engineering applications.

16.
J Biomed Biotechnol ; 2009: 289068, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19746176

RESUMO

Hepatitis B virus X protein (HBx) plays a crucial role in the development of hepatocellular carcinoma (HCC). However, the significance of circulating antibody to hepatitis B virus X antigen (anti-HBx) in sera remains unclear. In the present study, we examined the titers of anti-HBx (IgG) in the sera from 173 patients with chronic hepatitis B (CHB), 106 liver cirrhosis (LC), and 61 HCC by enzyme-linked immunosorbent assay (ELISA), respectively. Our data showed that the positive rates of anti-HBx were higher in sera of LC (40.6%) and HCC (34.4%) than those of CHB (10.4%), P < .05. In all 40 patients with anti-HBx+ out of 340 patients, 39 (97.5%) were HBsAg/HBeAg/anti-HBc+ and 1 (2.5%) was anti-HBs+ (P < .01), suggesting that anti-HBx in sera is a marker of HBV replication rather than a protective antibody. Thus, our findings reveal that circulating anti-HBx in sera is one of the markers of development of LC and HCC mediated by HBV.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma Hepatocelular/virologia , Anticorpos Anti-Hepatite/sangue , Hepatite B/sangue , Cirrose Hepática/virologia , Neoplasias Hepáticas/virologia , Transativadores/sangue , Adolescente , Adulto , Idoso , Animais , Biomarcadores Tumorais/imunologia , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/imunologia , Linhagem Celular Tumoral , Distribuição de Qui-Quadrado , Ensaio de Imunoadsorção Enzimática , Feminino , Hepatite B/imunologia , Hepatite B/virologia , Vírus da Hepatite B/imunologia , Vírus da Hepatite B/metabolismo , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Cirrose Hepática/sangue , Cirrose Hepática/imunologia , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/imunologia , Masculino , Pessoa de Meia-Idade , Coelhos , Transativadores/genética , Transativadores/imunologia , Proteínas Virais Reguladoras e Acessórias
17.
ACS Omega ; 4(6): 9828-9834, 2019 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-31460073

RESUMO

Butyl levulinate (BL) is a versatile chemical utilized widely in food and chemical industries, the production of which by using cellulose in biomass resources is of great significance to its sustainable development. Traditional synthesis processes for n-butyl levulinate are confronted with various problems such as high cost of raw materials, difficulty in separating products, etc. In this paper, a novel process for the preparation of BL from cellulose is proposed. The process is composed of five main unit operations including fed-batch hydrolysis, decolorization, extraction, esterification and purification. A 171.63 g/L concentration of the intermediate levulinic acid was obtained at the fifth feeding through the fed-batch hydrolysis process. The resin-activated carbon secondary decolorization method was adopted to remove the soluble humin byproducts with an accumulative decolorization rate of 89%. In the extraction process, the product BL was chosen as the extractant to avoid the introduction of new impurities. After purification, the purity of the final product BL reaches up to 98 wt %. The proposed technique allows for cost-effective and eco-friendly production of BL from biomass resources.

18.
Zhonghua Yi Xue Za Zhi ; 86(1): 61-5, 2006 Jan 03.
Artigo em Chinês | MEDLINE | ID: mdl-16606541

RESUMO

OBJECTIVE: To screen a sub-clone of human breast cancer cell of the MCF-7 line with high metastasis potential. METHODS: Human breast cancer cells of the MCF-7 line were injected subcutaneously into 10 severe combined immunodeficiency (SCID) mice. Sixty-eight days after the mice were killed and their lungs were taken out. Primary cell culture was conducted. When the cells were passed on to the third generation a sub-clone was screened from the lung tissue and termed LM-MCF-7. Microscopy was performed on the lung tissues. The growth curve was drawn. Flow cytometry was used to examine the cell cycle. Chromosome analysis was done. Immunohistochemistry was used to detect the expression of breast cancer specific antigen CAI5-3. Western blotting was used to detect the protein expression of the protein associated with tumor metastasis: nm23 (a metastasis-suppressing gene), myosin light chain kinase (MLCK, a kinase related to cell movement), survivin, bcl-2 and p27 (a gene related to cell cycle). LM-MCF-7 cells were injected into other SCID mice and these mice were killed 30 days later to observe the metastasis of cancer so as to detect the tumorigenic ability of the LM-MCF-7 cells. RESULTS: When the cells from the mouse lung tissues were passed on to the third generation a sub-clone with high metastasis potential was screened and termed LM-MCF-7. The morphology of the new cell line was typically epithelioid. Flow cytometry showed that the DNA relatively contents were 53.40% of the LM-MCF-7 cells were in the G(0)/G(1) phase, a lower percentage than that of the MCF-7 cells, and 17.10% in the S phase and 23.20% in the G(2+)M phase, both percentages higher than those of the MCF-7 cells. The proliferating time of the LM-MCF-7 cell population was about 20 +/- 14 hours, much shorter than that of the parent strain cells. The chromosomes of the LM-MCF-7 cells, numbering 16-123, showed the morphology characteristic c of human chromosomes. The marker of human breast cancer CA15-3 was detected in both MCF-7 and LM-MCF-7 cells. The protein expression of nm23 and p27 was down-regulated, but the protein expression of MLCK, bcl-2 and survivin was up-regulated in LM-MCF-7 cells in comparison with those in MCF-7 cells. The tumorigenesis rate of LM-MCF-7 cells was 100% (5/5), with a latent period of 5.0 +/- 0.0 d, and the tumor metastasized to lung, kidney, spleen, bone marrow, lymph node and heart. CONCLUSION: A human breast cancer line, LM-MCF-7 cell line, with high metastasis potential has been derived from the human breast cancer cells of MCF-7 line.


Assuntos
Neoplasias da Mama/patologia , Metástase Neoplásica/patologia , Animais , Western Blotting , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Células Clonais/metabolismo , Células Clonais/patologia , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Feminino , Citometria de Fluxo , Humanos , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Nus , Camundongos SCID , Quinase de Cadeia Leve de Miosina/metabolismo , Nucleosídeo NM23 Difosfato Quinases/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transplante Heterólogo , Proteínas Supressoras de Tumor/metabolismo
19.
Life Sci ; 73(9): 1189-98, 2003 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-12818726

RESUMO

Adriamycin tolerant human mesothelioma cell lines derived from a single tumor prior to either chemotherapy or radiation therapy and a susceptible cell line were investigated. Not only was growth resistant to low doses of adriamycin but an unusual pattern of resistance was encountered in which cells seemed to better tolerate high adriamycin doses than intermediate doses. The differential growth susceptibility of the tolerant lines compared to A549 lung carcinoma and the bimodal dose response correlated with differences in the specific activity of a plasma membrane-associated NADH oxidase (NOX). Plasma membrane fractions of high purity were isolated by aqueous two-phase partition and assayed directly. The NADH oxidase activity of the plasma membranes for the susceptible cell line was maximally inhibited by 1 microM adriamycin whereas the NADH oxidase activity of the tolerant lines was less and was maximally inhibited by 0.1 microM adriamycin with 1 and 10 microM adriamycin being less inhibitory than 0.1 microM adriamycin. The findings suggest a relationship between the growth response to adriamycin of the adriamycin tolerant mesothelioma lines and the activity of the plasma membrane-associated NADH oxidase activity of the cell surface in these cell lines.


Assuntos
Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Tolerância a Medicamentos , Mesotelioma/tratamento farmacológico , Complexos Multienzimáticos/metabolismo , NADH NADPH Oxirredutases/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/enzimologia , Relação Dose-Resposta a Droga , Doxorrubicina/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Mesotelioma/enzimologia , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/metabolismo
20.
Biofactors ; 20(4): 235-49, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15706060

RESUMO

Capsaicin and the principal green tea catechin, (-)-epigallocatechin-3-gallate (EGCg), target tNOX, a tumor (cancer)-specific surface hydroquinone (NADH) oxidase with protein disulfide-thiol interchange activity (ECTO-NOX protein). Accordingly vector-forced over expression of tNOX in MCF-10A mammary epithelia or COS cells that lack tNOX or in COS cells that underexpress tNOX enhanced the susceptibility of growth and apoptosis to both EGCg and capsaicin. Additionally, the tNOX-transfected MCF-10A cells proliferated in Matrigel, a measure of invasiveness. In contrast, oligomeric antisense tNOX DNA abrogated growth inhibition by EGCg and capsaicin and reduced anchorage-dependent growth of HeLa (human cervical carcinoma) cells that naturally overexpress tNOX. The findings show cell surface expression of tNOX as both necessary and sufficient for the cellular anticancer activities attributed to both EGCg and capsaicin.


Assuntos
Anticarcinógenos/farmacologia , Antineoplásicos/farmacologia , Capsaicina/farmacologia , Catequina/análogos & derivados , Catequina/farmacologia , NADH NADPH Oxirredutases/metabolismo , Animais , Mama , Células COS , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Chlorocebus aethiops , Células HeLa , Humanos , Rim , Cinética , NADH NADPH Oxirredutases/genética , Reação em Cadeia da Polimerase , Chá , Transfecção
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