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1.
J Clin Transl Hepatol ; 12(5): 457-468, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38779518

RESUMEN

Background and Aims: Hepatitis B virus (HBV) reactivation is commonly observed in individuals with chronic HBV infection undergoing antineoplastic drug therapy. Paclitaxel (PTX) treatment has been identified as a potential trigger for HBV reactivation. This study aimed to uncover the mechanisms of PTX-induced HBV reactivation in vitro and in vivo, which may inform new strategies for HBV antiviral treatment. Methods: The impact of PTX on HBV replication was assessed through various methods including enzyme-linked immunosorbent assay, dual-luciferase reporter assay, quantitative real-time PCR, chromatin immunoprecipitation, and immunohistochemical staining. Transcriptome sequencing and 16S rRNA sequencing were employed to assess alterations in the transcriptome and microbial diversity in PTX-treated HBV transgenic mice. Results: PTX enhanced the levels of HBV 3.5-kb mRNA, HBV DNA, HBeAg, and HBsAg both in vitro and in vivo. PTX also promoted the activity of the HBV core promoter and transcription factor AP-1. Inhibition of AP-1 gene expression markedly suppressed PTX-induced HBV reactivation. Transcriptome sequencing revealed that PTX activated the immune-related signaling networks such as IL-17, NF-κB, and MAPK signaling pathways, with the pivotal common key molecule being AP-1. The 16S rRNA sequencing revealed that PTX induced dysbiosis of gut microbiota. Conclusions: PTX-induced HBV reactivation was likely a synergistic outcome of immune suppression and direct stimulation of HBV replication through the enhancement of HBV core promoter activity mediated by the transcription factor AP-1. These findings propose a novel molecular mechanism, underscoring the critical role of AP-1 in PTX-induced HBV reactivation.

2.
Front Mol Biosci ; 11: 1378386, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38584703

RESUMEN

The consistent notion holds that hepatocellular carcinoma (HCC) initiation, progression, and clinical treatment failure treatment failure are affected by the accumulation of various genetic and epigenetic alterations. MicroRNAs (miRNAs) play an irreplaceable role in a variety of physiological and pathological states. meanwhile, epithelial-mesenchymal transition (EMT) is a crucial biological process that controls the development of HCC. miRNAs regulate the intermediation state of EMTor mesenchymal-epithelial transition (MTE)thereby regulating HCC progression. Notably, miRNAs regulate key HCC-related molecular pathways, including the Wnt/ß-catenin pathway, PTEN/PI3K/AKT pathway, TGF-ß pathway, and RAS/MAPK pathway. Therefore, we comprehensively reviewed how miRNAs produce EMT effects by multiple signaling pathways and their potential significance in the pathogenesis and treatment response of HCC. emphasizing their molecular pathways and progression in HCC initiation. Additionally, we also pay attention to regulatory mechanisms that are partially independent of signaling pathways. Finally, we summarize and propose miRNA-targeted therapy and diagnosis and defense strategies forHCC. The identification of the mechanism leading to the activation of EMT programs during HCC disease processes also provides a new protocol for the plasticity of distinct cellular phenotypes and possible therapeutic interventions. Consequently, we summarize the latest progress in this direction, with a promising path for further insight into this fast-moving field.

3.
Gut Liver ; 2023 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-37458065

RESUMEN

Background/Aims: Cancer stem cells (CSCs) are believed to drive tumor development and metastasis. Activin and hepatocyte growth factor (HGF) are important cytokines with the ability to induce cancer stemness. However, the effect of activin and HGF combination treatment on CSCs is still unclear. Methods: In this study, we sequentially treated colorectal cancer cells with activin and HGF and examined CSC marker expression, self-renewal, tumorigenesis, and metastasis. The roles of forkhead box M1 (FOXM1) and sex-determining region Y-box 2 (SOX2), two stemness-related transcription factors, in activin/HGF-induced aggressive phenotype were explored. Results: Activin and HGF treatment increased the expression of CSC markers and enhanced sphere formation in colorectal cancer cells. The tumorigenic and metastatic capacities of colorectal cancer cells were enhanced upon activin and HGF treatment. Activin and HGF treatment preferentially promoted stemness and metastasis of CD133+ subpopulations sorted from colorectal cancer cells. FOXM1 was upregulated by activin and HGF treatment, and the knockdown of FOXM1 blocked activin/HGF-induced stemness, tumorigenesis, and metastasis of colorectal cancer cells. Similarly, SOX2 was silencing impaired sphere formation of activin/HGF-treated colorectal cancers. Overexpression of SOX2 rescued the stem cell-like phenotype in FOXM1-depleted colorectal cancer cells with activin and HGF treatment. Additionally, the inhibition of FOXM1 via thiostrepton suppressed activin/HGF-induced stemness, tumorigenesis and metastasis. Conclusions: Sequential treatment with activin and HGF promotes colorectal cancer stemness and metastasis through activation of the FOXM1/SOX2 signaling. FOXM1 could be a potential target for the treatment of colorectal cancer metastasis.

4.
Gut Liver ; 2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36860162

RESUMEN

Background/Aims: Gastric intestinal metaplasia (GIM), a common precancerous lesion of gastric cancer, can be caused by bile acid reflux. GATA binding protein 4 (GATA4) is an intestinal transcription factor involved in the progression of gastric cancer. However, the expression and regulation of GATA4 in GIM has not been clarified. Methods: The expression of GATA4 in bile acid-induced cell models and human specimens was examined. The transcriptional regulation of GATA4 was investigated by chromatin immunoprecipitation and luciferase reporter gene analysis. An animal model of duodenogastric reflux was used to confirm the regulation of GATA4 and its target genes by bile acids. Results: GATA4 expression was elevated in bile acid-induced GIM and human specimens. GATA4 bound to the promoter of mucin 2 (MUC2) and stimulate its transcription. GATA4 and MUC2 expression was positively correlated in GIM tissues. Nuclear transcription factor-κB activation was required for the upregulation of GATA4 and MUC2 in bile acid-induced GIM cell models. GATA4 and caudal-related homeobox 2 (CDX2) reciprocally transactivated each other to drive the transcription of MUC2. In chenodeoxycholic acid-treated mice, MUC2, CDX2, GATA4, p50, and p65 expression levels were increased in the gastric mucosa. Conclusions: GATA4 is upregulated and can form a positive feedback loop with CDX2 to transactivate MUC2 in GIM. NF-κB signaling is involved in the upregulation of GATA4 by chenodeoxycholic acid.

5.
Artículo en Inglés | MEDLINE | ID: mdl-36901370

RESUMEN

Non-point source fugitive dust produced during municipal road construction is one of the main ambient air pollutants gravely threatening the life and health of construction workers and residents around construction areas. In this study, a gas-solid two-phase flow model is used to simulate the diffusion behavior of non-point source dust with different enclosure heights under wind loads. Moreover, the inhibitory effect of the enclosure on the diffusion of non-point source dust from construction to residential areas is analyzed. The results show that the physical blocking and reflux effects of the enclosure can effectively restrain dust diffusion. When the enclosure height is 3-3.5 m, the concentration of particulate matter in most sections of residential areas can be reduced to less than 40 µg/m3. Moreover, when the wind speed is 1-5 m/s and the enclosure height is 2-3.5 m, the diffusion height of non-point source dust particles above the enclosure is concentrated in the range 1.5-2 m. This study provides a scientific basis for setting the heights of enclosures and atomization sprinklers at construction sites. Further, effective measures are proposed to reduce the impact of non-point source dust on the air environment of residential areas and health of residents.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Humanos , Polvo/análisis , Monitoreo del Ambiente/métodos , Material Particulado/análisis , Contaminantes Atmosféricos/análisis , Viento , Contaminación del Aire/análisis
6.
Environ Sci Pollut Res Int ; 30(5): 12508-12520, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36109483

RESUMEN

Characterizing the anomalous diffusion behavior of sediment transport is a key factor in calculating sediment concentration. This study attempts to seek an equation that captures the nonlocal movement feature of the transport of an ensemble of sediment particles on ice-covered channels with a steady uniform flow field. Given that the fractional advection-dispersion equation with a noninteger order on the space term is nonlocal and able to describe the long-distance transport, a mathematical model with the Caputo fractional derivative is proposed to estimate the vertical diffusion of suspended sediment particles in the ice-covered channel. Results show that the fractional derivative model has a good predictive ability to the suspended sediment concentration as compared to the measurements. Especially in regions close to the undersurface of the ice cover, the proposed model matches better with experiments than the existing analytical model. Sensitivity analyses indicate that the strength of the turbulent diffusion effect dominates the uniformity of the sediment concentration profile. Besides, the sediment concentration is more sensitive to the variation of the boundary roughness than to the change of the sediment settling velocity. It should be noted that the sediment concentration reduces with the decrease of the order of the fractional derivative, which differs from the findings in previous studies.


Asunto(s)
Sedimentos Geológicos , Cubierta de Hielo , Modelos Teóricos , Difusión
8.
Gels ; 8(10)2022 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-36286163

RESUMEN

The mechanical properties of cementitious composites before and after exposure to high temperature are affected by calcium-silicate-hydrate (C-S-H) gels. To evaluate the effects of high temperature, plyvinyl alcohol (PVA) fiber content, and the cooling method on properties of cementitious composites, physical, mechanical, and microscopic tests were performed in this study. The target temperatures were 25, 100, 200, 300, 400, 600, and 800 °C. The PVA fiber contents were 0.0, 0.3, 0.6, 0.9, 1.2, and 1.5 vol%. The high-temperature resistance of PVA fiber-reinforced cementitious composite (PVA-FRCC) specimens was investigated through changes in their appearance, mass loss, compressive strength, splitting tensile strength, flexural strength, and microstructure. The results showed that PVA fibers reduced the probability of explosion spalling in the PVA-FRCC specimens exposed to high temperatures. The mass loss rate of samples exposed to temperatures below 200 °C was small and lower than 5%, whereas a significant mass loss was observed at 200 °C to 800 °C. A small rise in the cubic compressive and splitting tensile strengths of samples was found at 400 °C and 300 °C, respectively. Below 400 °C, the fibers were beneficial to the mechanical strength of the PVA-FRCC specimens. Nevertheless, when the temperature was heated above 400 °C, melted fibers created many pores and channels, which caused a decrease in the strength of the specimens. The method of cooling with water could aggravate the damage to the cementitious composites exposed to temperatures above 200 °C. High temperature could lead to the decomposition of the C-S-H gels of the PVA-FRCC samples, which makes C-S-H gels lose their bonding ability. From the perspective of the microstructure, the structure of PVA-FRCC samples exposed to 600 °C and 800 °C became loose and the number of microcracks increased, which confirmed the reduction in macro-mechanical properties.

9.
Toxics ; 10(8)2022 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-35893845

RESUMEN

A large quantity of particulate matter is generated during construction of civil engineering projects, which has a negative effect on the atmosphere and environment. In order to explore the concentration, distribution and diffusion of particulate matters generated from construction dust with different moisture contents, a wind tunnel experiment was conducted, and the effects of wind speed and moisture content on the inhibition rate, drifting distance and suppression percentage of particulate matters were investigated. The results show that the peak concentration decreases with the increase in moisture content, compared with dry dust; the peak concentrations for 1%, 2% and 3% moisture content are reduced by 37.07%, 39.53% and 65.38%, respectively. The average concentrations in the cross-section decrease with the increase in the moisture content, resulting in an increasing tendency of the particle inhibition rate. The forecast drifting distance decreases with the increase in the moisture content; when the suspension percentage is 1%, the forecast drifting distances of dry dust, 1%, 2% and 3% moisture content are 641.58, 116.08, 19.33 and 3.82 km, respectively, for a 5 m/s wind speed. Considering that an increase in wind velocity will not only decrease the inhibition rate but also increase the drifting distance, the dust suppression method by increasing the moisture content in low and medium wind velocities is applicable. When the limit value of the particle suppression rate within a distance of 50 m is larger than 70%, construction activities are prohibited at any wind velocity for dry and 1% moisture content, and at wind velocities larger than 2 m/s and 4 m/s for 2% and 3% moisture content, respectively.

10.
Gels ; 8(6)2022 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-35735685

RESUMEN

Geopolymers are environmentally friendly materials made from industrial solid waste with high silicon and aluminum contents, and municipal solid waste incineration fly ash (MFA) contains active ingredients such as Si, Al and Ca. According to this fact, a green and low-carbon geopolymer concrete was prepared using MFA as a partial replacement for metakaolin in this study. The mechanical properties of the MFA geopolymer concrete (MFA-GPC) were investigated through a series of experiments, including a compressive strength test, splitting tensile strength test, elastic modulus test and three-point bending fracture test. The effect of the MFA replacement ratio on the microstructure of MFA-GPC was investigated by SEM test, XRD analysis and FTIR analysis. MFA replacement ratios incorporated in GPC were 5%, 10%, 15%, 20%, 25%, 30%, 35% and 40% by replacing metakaolin with equal quality in this study. In addition, toxic leaching tests of MFA and MFA-GPC were performed by ICP-AES to evaluate the safety of MFA-GPC. The results indicated that the mechanical properties of MFA-GPC decreased with the increase of the MFA replacement ratio. Compared with the reference group of GPC without MFA, the maximum reduction rates of the cubic compressive strength, splitting tensile strength, axial compressive strength, elastic modulus, initiation fracture toughness, unstable fracture toughness and fracture energy of MFA-GPC were 83%, 81%, 78%, 93%, 77%, 73% and 61%, respectively. The microstructure of MFA-GPC was porous and carbonized; however, the type of hydrated gel products was still a calcium silicoaluminate-based silicoaluminate gel. Moreover, the leaching content of heavy metals from MFA-GPC was lower than that of the standard limit. In general, the appropriate amount of MFA can be used to prepare GPC, and its mechanical properties can meet the engineering requirements, but the amount of MFA should not be too high.

11.
Front Endocrinol (Lausanne) ; 13: 1087260, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36726464

RESUMEN

Non-alcoholic fatty liver disease (NAFLD) is a series of diseases, involving excessive lipid deposition in the liver and is often accompanied by obesity, diabetes, dyslipidemia, abnormal blood pressure, and other metabolic disorders. In order to more accurately reflect its pathogenesis, an international consensus renamed NAFLD in 2020 as metabolic (dysfunction) associated with fatty liver disease (MAFLD). The changes in diet and lifestyle are recognized the non-drug treatment strategies; however, due to the complex pathogenesis of NAFLD, the current drug therapies are mainly focused on its pathogenic factors, key links of pathogenesis, and related metabolic disorders as targets. There is still a lack of specific drugs. In clinical studies, the common NAFLD treatments include the regulation of glucose and lipid metabolism to protect the liver and anti-inflammation. The NAFLD treatments based on the enterohepatic axis, targeting gut microbiota, are gradually emerging, and various new metabolism-regulating drugs are also under clinical development. Therefore, this review article has comprehensively discussed the research advancements in NAFLD treatment in recent years.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Humanos , Enfermedad del Hígado Graso no Alcohólico/terapia , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Obesidad/metabolismo , Dieta
12.
Can J Gastroenterol Hepatol ; 2022: 8996203, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36591565

RESUMEN

Background: Cancer stem cells (CSCs) are involved in liver metastasis in colorectal cancer (CRC). Activin and hepatocyte growth factor (HGF) are important regulators of stem cell properties. This study was performed to explore the effect of activin and HGF on CRC invasion and metastasis. The key genes involved in the action of activin and HGF in CRC were identified. Methods: HCT116 CRC cells were sequentially treated with activin and HGF and examined for migration and invasion in vitro and liver metastasis in vivo. RNA sequencing was performed to identify differentially expressed genes in response to activin and HGF. Results: Sequential treatment with activin and HGF-enhanced CRC cell migration, invasion, and metastasis. CXCR4 and AFP expressions were increased by activin and HGF treatment. Knockdown of FOXM1 blocked liver metastasis from HCT116 cells pretreated with activin and HGF and suppressed CXCR4 and AFP expression. Activin alone increased the mRNA and protein expression of FOXM1. In contrast, HGF alone enhanced the phosphorylation of FOXM1, without altering the total protein level of FOXM1. SMAD2 was required for activin-mediated FOXM1 induction. FOXM1 transactivated CXCR4 by directly binding to the promoter of CXCR4. Additionally, CXCR4 regulated AFP expression through the NF-κB pathway. Conclusions: Sequential treatment with activin and HGF accelerates CRC invasion and liver metastasis, which involves the upregulation and activation of FOXM1 and induction of CXCR4 and AFP.


Asunto(s)
Neoplasias Colorrectales , Neoplasias Hepáticas , Humanos , alfa-Fetoproteínas/metabolismo , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Proteína Forkhead Box M1/genética , Proteína Forkhead Box M1/metabolismo , Factor de Crecimiento de Hepatocito/farmacología , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/secundario , Regulación hacia Arriba , Activinas/farmacología
13.
Materials (Basel) ; 14(17)2021 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-34501175

RESUMEN

The application of concrete containing mineral admixtures was attempted in Northwest China in this study, where the environment has the characteristics of low humidity and large temperature variation. The harsh environment was simulated by using an environmental chamber in the laboratory and four types of concrete were prepared, including ordinary concrete and three kinds of mineral admixture concretes with different contents of fly ash and blast-furnace slag. These concretes were cured in the environmental chamber according to the real curing conditions during construction. The compression strength, fracture properties, SEM images, air-void characteristics, and X-ray diffraction features were researched at the early ages of curing before 28 d. The results showed that the addition of fly ash and slag can improve the compression strength and fracture properties of concrete in the environment of low humidity and large temperature variation. The optimal mixing of mineral admixture was 10% fly ash and 20% slag by replacing the cement in concrete, which can improve the compression strength, initial fracture toughness, unstable fracture toughness, and fracture energy by 23.9%, 25.2%, 45.3%, and 22.6%, respectively, compared to ordinary concrete. Through the analysis of the microstructure of concrete, the addition of fly ash and slag can weaken the negative effects of the harsh environment of low humidity and large temperature variation on concrete microstructure and cement hydration.

14.
BMC Infect Dis ; 21(1): 406, 2021 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-33941096

RESUMEN

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic continues to expand. Herein, we report the epidemiological and clinical features of 478 patients with confirmed COVID-19 from a multicenter study conducted in four cities in China excluding Wuhan. METHODS: A total of 478 patients transferred by emergency medical services to designated hospitals in four major cities in China (Beijing, Chongqing, Jinan, and Nanning) were enrolled. We compared the characteristics of imported and indigenous cases and calculated the frequencies of fatal, severe, mild, and asymptomatic disease. The results were used to generate a pyramid of COVID-19 severity. RESULTS: The mean age of patients with COVID-19 was 46.9 years and 49.8% were male. The most common symptoms at onset were fever (69.7%), cough (47.5%), fatigue (24.5%), dyspnea (8.4%), and headache (7.9%). Most cases (313, 65.5%) were indigenous, while 165 (34.5%) were imported. Imported cases dominated during the early stages of the pandemic, but decreased from 1 February 2020 as indigenous cases rose sharply. Compared with indigenous cases, imported cases differed significantly in terms of sex (P = 0.002), severity of disease (P = 0.006), occurrence of fever (P < 0.001), family clustering (P < 0.001), history of contact (P < 0.001), and primary outcome (P < 0.001). CONCLUSIONS: Within the population studied, imported cases had distinct characteristics from those of indigenous cases, with lower fatality rates and higher discharge rates. New infections shifted from imported cases to local infection gradually, and overall infections have declined to a low level. We suggest that preventing import of cases and controlling spread within local areas can help prevent SARS-CoV-2 infection spread.


Asunto(s)
COVID-19/epidemiología , COVID-19/etiología , Adolescente , Adulto , Anciano , Beijing/epidemiología , COVID-19/terapia , China/epidemiología , Tos/epidemiología , Tos/virología , Fatiga/epidemiología , Fatiga/virología , Femenino , Fiebre/epidemiología , Fiebre/virología , Humanos , Masculino , Persona de Mediana Edad , Alta del Paciente , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
15.
Med Sci Monit ; 26: e923985, 2020 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-32546678

RESUMEN

BACKGROUND In December 2019, an outbreak of coronavirus disease 2019 (COVID-19), due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), occurred in Wuhan, China. Patients with COVID-19 were also identified in Chongqing. This study aimed to investigate the clinical and demographic characteristics of cluster cases and sporadic cases of COVID-19 in 141 patients in the main district of Chongqing during one month, between January and February 2020. MATERIAL AND METHODS A retrospective study included 141 patients with a diagnosis of COVID-19. The diagnosis was confirmed using real-time reverse transcription-polymerase chain reaction (RT-PCR) for SARS-CoV-2. The patients were divided into cluster cases (n=90) and sporadic cases (n=51). Demographic and clinical characteristics were compared between the two study groups and included the presence of comorbidities, the presenting symptoms, chest computed tomography (CT) imaging findings, and laboratory findings. RESULTS The mean age of the 141 patients diagnosed with COVID-19 was 47.3 years, and the most common presenting symptom was a persistent cough (48.9%). The 90 cluster cases (63.8%) were older than the sporadic cases, and cross-infection from family gathering occurred in 82.2%, and cough was more common than fever, and there was an increased prevalence of asymptomatic, mild, and moderate cases. Cluster cases showed fewer typical manifestations of COVID-19 on chest CT. However, the laboratory findings between the cluster and sporadic cases showed no significant differences. CONCLUSIONS There were demographic and clinical differences between cluster cases and sporadic cases of COVID-19 in the main district of Chongqing during the month between January to February 2020.


Asunto(s)
Betacoronavirus/fisiología , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/virología , Demografía , Neumonía Viral/epidemiología , Neumonía Viral/virología , COVID-19 , China/epidemiología , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pandemias , Neumonía Viral/diagnóstico , Neumonía Viral/diagnóstico por imagen , SARS-CoV-2 , Tomografía Computarizada por Rayos X
16.
J Formos Med Assoc ; 119(7): 1180-1184, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32386675

RESUMEN

BACKGROUND: We did a comprehensive exploration of the epidemiological and clinical characteristics of 136 patients with confirmed COVID-19 in main district of Chongqing which was adjacent to the west of Hubei province. METHODS: This study was conducted on 136 patients with COVID-19 in main district of Chongqing from Jan 25 to Feb 20, 2020. Data of patients included demographic, epidemiological, clinical features, chest radiographs of imported cases, local cases, second-generation cases and third-generation cases. Student's t-test was adopted for quantitative variables while Pearson Chi-squared test or Fisher's exact test for categorical variables. RESULTS: The median age was 47 years and common symptoms of illness were cough (50.7%), fever (47.1%) and fatigue (14.0%). The time from contact symptomatic case to illness was 7.7 days, and 88 patients (64.7%) were cluster cases, radiological evidence found bilateral lung involvement was common (57.4%).Compared with the imported cases, the local cases were significantly older, the proportion of men is lower. There was higher proportion of cluster cases in local cases. Unlike imported cases, which fever was the dominant symptom, the local cases have more cough patients, with a significant higher proportion of asymptomatic patients. The third-generation cases have a significant higher proportion of asymptomatic patients. CONCLUSION: We concluded the epidemiological and clinical characteristics of the cases andsuggested to take more comprehensive measures for screening patients, especially for elderly person, avoid family gatherings, and implement more closely surveillance of suspect patients and their close contacts.


Asunto(s)
Infecciones Asintomáticas/epidemiología , Infecciones por Coronavirus , Transmisión de Enfermedad Infecciosa/prevención & control , Pandemias , Neumonía Viral , Evaluación de Síntomas , Factores de Edad , Betacoronavirus/aislamiento & purificación , COVID-19 , China/epidemiología , Análisis por Conglomerados , Trazado de Contacto/métodos , Trazado de Contacto/estadística & datos numéricos , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/fisiopatología , Infecciones por Coronavirus/prevención & control , Infecciones por Coronavirus/terapia , Tos/diagnóstico , Tos/etiología , Fatiga/diagnóstico , Fatiga/etiología , Femenino , Fiebre/diagnóstico , Fiebre/etiología , Humanos , Masculino , Persona de Mediana Edad , Pandemias/prevención & control , Neumonía Viral/diagnóstico , Neumonía Viral/diagnóstico por imagen , Neumonía Viral/epidemiología , Neumonía Viral/etiología , Neumonía Viral/fisiopatología , Neumonía Viral/prevención & control , Neumonía Viral/terapia , Radiografía Torácica/métodos , Radiografía Torácica/estadística & datos numéricos , SARS-CoV-2 , Factores Sexuales , Evaluación de Síntomas/métodos , Evaluación de Síntomas/estadística & datos numéricos
17.
Materials (Basel) ; 13(8)2020 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-32326462

RESUMEN

The freezing and thawing of construction concrete is becoming an increasingly important structural challenge. In this study, a shrinkage-compensating concrete based on a double expansive admixture was developed and its frost resistance was assessed through rapid freezing and thawing cycling. The frost resistance of the concrete was derived through the measurement and calculation of the relative dynamic modulus of elasticity (RDME) and the mass loss rate (MLR), and the freezing- and thawing-cycle microstructures and products of concretes with different expansive agents were analyzed using scanning electron microscopy (SEM). It was shown that changes in the properties of the concrete under freezing and thawing could be divided into three stages: slow-damage stage, fast-damage stage, and stable stage. Compared to concrete without an expansive agent, a single-expansive-agent concrete demonstrated excellent frost resistance during the slow-damage stage, but the frost resistance rapidly decreased during the fast-damage age. After 150 cycles (the stable-damage stage), the concrete with a U-type expansive agent (UEA): MgO expansive agent (MEA) mix proportion of 2:1 had the best frost resistance, with RDME and MLR values 17.35% higher and 25.1% lower respectively, than that of an expansive-agent-free concrete. These test results provide a basis for the study of frost resistance in large-scale hydraulic concrete structures.

18.
Materials (Basel) ; 13(5)2020 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-32121629

RESUMEN

Carbon nanotubes (CNTs) are very effective in improving the performance of cement-based materials. Mechanical properties and pore structure were investigated for cement mortar with CNTs. Meanwhile, the composite morphology of CNT-cement material and the evolution of hydration products were observed by scanning electron microscope (SEM), and the quantitative relationship between mechanical properties and pore structure was analyzed. The results indicated that the strength of mortar increased with the addition of 0.05% CNTs and decreased when the fraction of CNTs increased to 0.5%. The porosity of mortar with dispersed CNTs increased significantly, as these pores may be introduced by the dispersant. The quantitative relationship between porosity and strength proved that the increased porosity is the reason for the decreased strength of mortar with 0.5% CNT content, while mortar matrix strength with 0.05% and 0.5% CNTs increased by 44.03% and 71.18%, respectively. SEM images show that CNTs are dispersed uniformly in the mortar without obvious agglomeration and that the CNTs and hydration products form a meshwork structure, which is the mechanism by which CNTs can enhance the strength of the cement matrix.

19.
Materials (Basel) ; 12(17)2019 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-31461992

RESUMEN

In order to explore the drying-wetting cycle test method of concrete under sulfate accelerating erosion, the influence of dry-wet time ratio on concrete sulfate erosion was studied. Under the condition of 7 days for one cycle, five different dry-wet time ratios were designed: 1:3, 1:1, 3:1, 5:1, and 10:1. The basic properties such as compressive strength, splitting tensile strength and dynamic elastic modulus of concrete were tested. Scanning electron microscopy (SEM) was used to analyze the microstructure of concrete before and after erosion. The test results show that under the environment of sulfate drying-wetting cycle erosion, the change of mechanical properties of concrete are divided into three stages: ascending period, fluctuating period and rapid descending period. Concrete is subjected to periodic damage process of initial damage followed by filling compaction, cracking, further filling, and cracking again, in that order. Dry-wet ratio has a significant effect on concrete sulfate attack. Under the same drying-wetting cycle period, as the dry-wet ratio increases, the degree of deterioration of concrete by sulfate attack increases first and then decreases. When the dry-wet ratio is 5:1, the deterioration is the most serious.

20.
Ann Hepatol ; 17(6): 940-947, 2018 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-30600290

RESUMEN

INTRODUCTION AND AIM: Hepatitis B virus (HBV) infection remains a public health problem worldwide. In addition, HBV infection results are influenced by various virological, immunological, and genetic factors. Inducible T-cell costimulator (ICOS) polymorphisms involving chronic HBV infection have been confirmed in previous studies. This study was to explore the effects of ICOS single nucleotide polymorphisms in HBV subtypes and their interactions with viral mutations on HBV infection outcomes. MATERIAL AND METHODS: A total of 1,636 Han Chinese individuals were recruited, including 47 asymptomatic HBV carriers (ASC), 353 chronic hepatitis B (CHB) patients, 327 HBV-related liver cirrhosis (LC) patients, 193 HBV-related hepatocellular carcinoma (HCC) patients, 464 patients with spontaneous recovery from HBV infection (SR), and 252 healthy controls (HC). DNA samples from these subjects were genotyped for four ICOS SNPs (rs11883722, rs10932029, rs1559931, and rs4675379). Direct sequencing was used to determine the HBV mutations in the enhancer II, basal core promoter, and pre-core regions. RESULTS: We found that the genotype "TC" of ICOS rs10932029 SNP was associated with decreased HBV-related LC risk in the genotype C group. Additionally, the A1762T, G1764A and A1762T/G1764A mutations were associated with an increased risk of LC in the genotype C group. Further study indicated that interactions between ICOS rs10932029 genotype "TC" and A1762T or A1762T/G1764A mutations significantly decreased the LC risk in the genotype C group. CONCLUSION: The rs10932029 genotype "TC" might be an LC-protective factor for HBV genotype C infection. The interactions between the rs10932029 genotype "TC" and A1762T or A1762T/G1764A mutations could decrease the risk of LC.


Asunto(s)
ADN Viral/genética , Virus de la Hepatitis B/genética , Hepatitis B Crónica/genética , Hepatitis B Crónica/virología , Proteína Coestimuladora de Linfocitos T Inducibles/genética , Mutación , Polimorfismo de Nucleótido Simple , Adulto , Anciano , Pueblo Asiatico/genética , Carcinoma Hepatocelular/etnología , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/virología , Estudios de Casos y Controles , China/epidemiología , Estudios Transversales , Femenino , Predisposición Genética a la Enfermedad , Hepatitis B Crónica/diagnóstico , Hepatitis B Crónica/etnología , Interacciones Huésped-Patógeno , Humanos , Cirrosis Hepática/etnología , Cirrosis Hepática/genética , Cirrosis Hepática/virología , Neoplasias Hepáticas/etnología , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/virología , Masculino , Persona de Mediana Edad , Fenotipo , Pronóstico , Factores Protectores , Factores de Riesgo
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