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1.
PLoS One ; 17(8): e0273542, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36001597

RESUMEN

PURPOSE: Cardiac fibrosis is characterized by the excessive deposition of extracellular matrix (ECM) proteins and leads to the maladaptive changes in myocardium. Endothelial cells (ECs) undergoing mesenchymal transition contributes to the occurrence and development of cardiac fibrosis. CD146 is an adhesion molecule highly expressed in ECs. The present study was performed to explore the role of CD146 in modulating endothelial to mesenchymal transition (EndMT). METHODS: C57BL/6 mice were subjected to subcutaneous implantation of osmotic minipump infused with angiotensin II (Ang Ⅱ). Adenovirus carrying CD146 short hairpin RNA (shRNA) or CD146 encoding sequence were infected into cultured human umbilical vein endothelial cells (HUVECs) followed by stimulation with Ang II or transforming growth factor-ß1 (TGF-ß1). Differentially expressed genes were revealed by RNA-sequencing (RNA-Seq) analysis. Gene expression was measured by quantitative real-time PCR, and protein expression and distribution were determined by Western blot and immunofluorescence staining, respectively. RESULTS: CD146 was predominantly expressed by ECs in normal mouse hearts. CD146 was upregulated in ECs but not fibroblasts and myocytes in hearts of Ang II-infused mice and in HUVECs stimulated with Ang Ⅱ. RNA-Seq analysis revealed the differentially expressed genes related to EndMT and Wnt/ß-catenin signaling pathway. CD146 knockdown and overexpression facilitated and attenuated, respectively, EndMT induced by Ang II or TGF-ß1. CD146 knockdown upregulated Wnt pathway-related genes including Wnt4, LEF1, HNF4A, FOXA1, SOX6, and CCND3, and increased the protein level and nuclear translocation of ß-catenin. CONCLUSIONS: Knockdown of CD146 exerts promotional effects on EndMT via activating Wnt/ß-catenin pathway and the upregulation of CD146 might play a protective role against EndMT and cardiac fibrosis.


Asunto(s)
Factor de Crecimiento Transformador beta1 , beta Catenina , Animales , Antígeno CD146/genética , Antígeno CD146/inmunología , Antígeno CD146/metabolismo , Células Cultivadas , Transición Epitelial-Mesenquimal , Fibrosis , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Ratones , Ratones Endogámicos C57BL , Factor de Crecimiento Transformador beta1/metabolismo , Vía de Señalización Wnt , beta Catenina/metabolismo
2.
Ying Yong Sheng Tai Xue Bao ; 33(5): 1275-1282, 2022 May.
Artículo en Chino | MEDLINE | ID: mdl-35730086

RESUMEN

The spatial pattern of plant population is one of primary issues in ecological research. Point pattern analy-sis is considered as an important method to study the spatial pattern of plant population. Ripley's K function has been commonly used for point pattern analysis. However, the cumulative effect of Ripley's K function may lead to specific spatial pattern charcteristics. To explore how the cumulative effect of Ripley's K function affects population pattern, the data of clumped distribution, random distribution and regular distribution of Stipa grandis were simulated by R software. All data generated by R software were analyzed by Ripley's K function and the non-cumulative pairwise correlation function g(r). The results showed that for clumped distribution (or regular distribution), the cumulative effect of Ripley's K function was manifested in two aspects. On the one hand, the scale of clumped distribution (or regular distribution) was increased due to Ripley's K function. On the other hand, Ripley's K function could detect the difference of the distribution of cluster (or negative interaction range) in the sampling space, exhibiting different pattern characteristics. For random distribution, Ripley's K function had no cumulative effect. In conclusion, the combination of Ripley's K function and pairwise correlation function by collecting replicate samples could better reveal the essential characteristics of the pattern in the study of population pattern.


Asunto(s)
Poaceae , Programas Informáticos
3.
World J Clin Cases ; 9(24): 7053-7061, 2021 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-34540960

RESUMEN

BACKGROUND: Fracture risk assessment in children with benign bone lesions of long bones remains poorly investigated. AIM: To investigate the risk factors for pathological fracture in children with benign bone lesions and to propose a modified scoring system for quantitative analysis of the pathologic fracture risk. METHODS: We retrospectively reviewed 96 pediatric patients with benign bone lesions. We compared radiographic and clinical features between 40 patients who had fractures through a benign bone lesion and 56 who had no fracture. Information including histological diagnosis, anatomical site, radiographic appearance, severity of pain, and lesion size was recorded for the patients. A modified scoring system was proposed to predict the risk of fracture. RESULTS: The univariate comparisons showed a significant difference between the fracture and non-fracture groups in terms of lesion type, pain, lesion-to-bone width, and axial cortical involvement of the patients (P < 0.05). Lesion type, pain, lesion-to-bone width, and axial cortical involvement were independently correlated with an increased risk of fracture. The mean score of the fracture group was 7.89, whereas the mean score of the non-fracture group was 6.01. The optimum cut-off value of the score to predict pathological fracture was 7. The scoring system had a sensitivity of 70% and a specificity of 80% for detecting patients with fractures. The Youden index was 0.5, which was the maximum value. The area under the receiver operator characteristic was 0.814. CONCLUSION: Lesion type, pain, lesion-to-bone width, and axial cortical involvement are risk factors for pathological fracture. The modified scoring system can provide evidence for clinical decision-making in children with benign bone lesions. A bone lesion with a total score > 7 indicates a high risk of a pathologic fracture and is an indication for prophylactic internal fixation.

4.
Nanotechnology ; 28(4): 045710, 2017 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-28000621

RESUMEN

Since manipulating electromagnetic waves with electromagnetic active materials for environmental and electric engineering is a significant task, here a novel prototype is reported by introducing reduced graphene oxide (RGO) interfaces in carbon fiber (CF) networks for a hierarchical carbon fiber/reduced graphene oxide/nickel (CF-RGO-Ni) composite textile. Upon charaterizations of the microscopic morphologies, electrical and magnetic properties, the presence of three-dimensional RGO interfaces and bifunctional nickel nanoparticles substantially influences the related physical properties in the resulting hierarchical composite textiles. Eletromagnetic interference (EMI) shielding performance suggests that the hierarchical composite textiles hold a strong shielding effectiveness greater than 61 dB, showing greater advantages than conventional polymeric and foamy shielding composites. As a polymer-free lightweight structure, flexible CF-RGO-Ni composites of all electromagnetic active components offer unique understanding of the multi-scale and multiple mechanisms in electromagnetic energy consumption. Such a novel prototype of shielding structures along with convenient technology highlight a strategy to achieve high-performance EMI shielding, coupled with a universal approach for preparing advanced lightweight composites with graphene interfaces.

5.
Org Lett ; 18(9): 2012-5, 2016 05 06.
Artículo en Inglés | MEDLINE | ID: mdl-27123866

RESUMEN

A practical and straightforward access to pyrazolo[3,4-c]quinolines by molecular sieve mediated dehydrogenative [2 + 2 + 1] heteroannulation of N-(o-alkenylaryl)imines with aryldiazonium salts is described using a sp(3)-hybrid carbon atom as a one-carbon unit. The reaction enables the formation of three new chemical bonds, a C-C bond and two C-N bonds, in a single reaction and features simple operation and excellent functional group tolerance.

6.
Chem Commun (Camb) ; 51(56): 11325-8, 2015 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-26084756

RESUMEN

A new copper-catalyzed oxidative difunctionalization of enol ethers with α-amino carbonyl compounds and hydroperoxides is developed. This method is experimentally simple while allowing for regioselective access to 2-amino-3,4-dioxy carbonyl compounds in good yields, and represents the first example of alkene oxyalkylation through C(sp(3))-H functionalization.

7.
Chem Commun (Camb) ; 51(6): 1024-6, 2015 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-25446150

RESUMEN

A novel metal-free oxidative 1,2-alkylarylation of unactivated alkenes with the α-C(sp(3))-H bonds of acetonitriles for the synthesis of 5-oxo-pentanenitriles is presented. In the presence of TBPB (tert-butyl peroxybenzoate), a variety of α-aryl allylic alcohols underwent the 1,2-alkylarylation reaction with acetonitriles, giving 5-oxo-pentanenitriles in good to excellent yields. This method proceeds via the C(sp(3))-H oxidative coupling with the C-C double bond and 1,2-aryl-migration, and represents a new access to acyclic molecules through metal-free oxidative alkene 1,2-alkylarylation.

8.
Chem Commun (Camb) ; 50(85): 12867-9, 2014 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-25212419

RESUMEN

A new oxidative coupling of unactivated terminal alkenes with amides using peroxides is described, in which mono- and difunctionalization of alkenes are selectively achieved. In this reaction with amides, the chemoselectivity toward the functionalization of the C(sp(3))-H bonds adjacent to the nitrogen atom or the functionalization of the carbonyl C(sp(2))-H bonds across alkenes relies on the reaction conditions.

9.
Anesth Analg ; 118(3): 598-603, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24557106

RESUMEN

BACKGROUND: Epidural analgesia is generally accepted as the most effective form of pain relief during labor. Remifentanil patient-controlled IV analgesia (PCIA), which is less invasive than epidural analgesia, may be an attractive alternative. In this meta-analysis, we compared the efficacy and safety of the 2 analgesic techniques for labor pain. METHODS: Databases of PubMed, EMBASE, and Cochrane Library were searched independently by 2 reviewers to retrieve eligible randomized controlled clinical trials. The primary end points were pain scores at 1 and 2 hours, and the secondary end points were nausea, vomiting, pruritus, and umbilical artery pH values. Mean difference (MD) or risk ratio with 95% confidence intervals (CIs) were calculated for each end point. GRADE profiler was applied to assess the quality of evidence. RESULTS: Five eligible trials were retrieved and analyzed. We found that parturients with remifentanil PCIA had higher visual analog scale (10-cm scale) pain scores than those who received epidural analgesia at 1 hour (MD = 1.9 cm; 95% CI, 0.5-3.3; I = 94%) and 2 hours (MD = 3.0 cm; 95% CI, 0.7-5.2; I = 89%) after initiation of analgesia. There was no statistical difference between epidural analgesia and remifentanil PCIA in the incidence of nausea, vomiting, pruritus, or umbilical artery pH values. However, the CIs are quite wide and contain clinically significant differences. According to GRADE profiler, most end points had moderate quality except that pain scores at 1 hour were of low quality. CONCLUSIONS: This meta-analysis suggests that remifentanil PCIA is not superior to epidural analgesia in analgesic efficacy during labor. Given the wide CIs of the pooled results for secondary maternal and neonatal outcomes, definite conclusions cannot be drawn for those outcomes. Further studies are still warranted to validate these conclusions.


Asunto(s)
Analgesia Epidural/métodos , Analgesia Controlada por el Paciente/métodos , Anestésicos Intravenosos/administración & dosificación , Dolor de Parto/tratamiento farmacológico , Piperidinas/administración & dosificación , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Femenino , Humanos , Dolor de Parto/diagnóstico , Embarazo , Remifentanilo
10.
Science ; 340(6140): 1555-9, 2013 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-23812711

RESUMEN

Permeability controls fluid flow in fault zones and is a proxy for rock damage after an earthquake. We used the tidal response of water level in a deep borehole to track permeability for 18 months in the damage zone of the causative fault of the 2008 moment magnitude 7.9 Wenchuan earthquake. The unusually high measured hydraulic diffusivity of 2.4 × 10(-2) square meters per second implies a major role for water circulation in the fault zone. For most of the observation period, the permeability decreased rapidly as the fault healed. The trend was interrupted by abrupt permeability increases attributable to shaking from remote earthquakes. These direct measurements of the fault zone reveal a process of punctuated recovery as healing and damage interact in the aftermath of a major earthquake.


Asunto(s)
Desastres , Terremotos , Agua Subterránea , China
11.
Org Lett ; 13(13): 3392-5, 2011 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-21630700

RESUMEN

A calix[4]arene lipoic acid (C4LA) was synthesized by click chemistry in 62% yield. It was immobilized on Au surfaces via self-assembly to offer C4LA Self-Assembled Monolayers (SAMs). The SAMs show wettability and electrochemical impedance dual-signal response for methomyl with highly sensitivity and selectivity.


Asunto(s)
Calixarenos/química , Carbamatos/química , Plaguicidas/química , Ácido Tióctico/análogos & derivados , Ácido Tióctico/química , Humectabilidad , Impedancia Eléctrica , Oro/química , Estructura Molecular , Propiedades de Superficie
12.
Huan Jing Ke Xue ; 29(4): 1124-32, 2008 Apr.
Artículo en Chino | MEDLINE | ID: mdl-18637373

RESUMEN

Through the experiments of leaching and melting on the fly ash of medical wastes, the influence of leaching time, L/S, pH and grain size on the leaching characteristics of heavy metal and the effect of melting on the stabilization of fly ash are studied. Results show that, following the leaching time extending, the leaching concentrations of heavy metals and lixiviate toxicity of heavy metals increase in the fly ash. When the ratio of liquid and solid add, the leaching concentrations of heavy metals obviously become big, and the Cd's leaching concentration is the biggest, when the ratio of liquid and solid is 90, the Cd' s leaching ratio exceed the percent of 70. At the time pH is about 7, the leaching concentrations of heavy metals are the lowest. When the grain size is the bigger or little, the leaching concentrations of heavy metals are lower, however when the grain size is 250-900 microm, the concentrations are higher. After fly ash melt in the high temperature, the lixiviate toxicity of heavy metals greatly reduce, which explains that the effect of melting on heavy metals' stabilization is very good.


Asunto(s)
Carbono/química , Incineración , Eliminación de Residuos Sanitarios/métodos , Metales Pesados/química , Material Particulado/química , Carbono/análisis , Ceniza del Carbón , Contaminación Ambiental/análisis , Contaminación Ambiental/prevención & control , Metales Pesados/análisis , Material Particulado/análisis , Reproducibilidad de los Resultados
13.
Zhonghua Yu Fang Yi Xue Za Zhi ; 41 Suppl: 62-5, 2007 Jun.
Artículo en Chino | MEDLINE | ID: mdl-17767860

RESUMEN

OBJECTIVE: To investigate the time trends of cancer mortality among residents in Kaifeng county, Henan province. METHODS: Data on cancer mortality from the vital registration system in Kaifeng county from 1988 to 2005 was analyzed. A total of 9543 death records (5974 males and 3567 females) due to malignant tumors were studied. A two-year-period age-specified standardized mortality rates were directly adjusted by the world standard population, and the annual percentage change (APC) of mortality were estimated by a linear logarithm regression. RESULTS: The crude cancer death rate for male was 95.09/100,000 and its age-standardized death rate was 117.41/100,000. While, the crude cancer death rate for female was 59.13/100,000 and the age-standardized death rate was 57.15/100,000. There was a significant growth tread for lung cancer (APC: 6.54%), liver cancer (5.07%) in males and breast cancer (7.04%) in females in the groups aged over 18. On the contrary, the decreasing treads for esophageal cancer in both of sexes (-7.09%, -13.53%) were also observed in this study. Meanwhile, there was no other significant changes in the trend, either in the tumor sites or mortality, was observed. CONCLUSION: In the past two decades, there has been a significant increasing trend for cancer mortality in Kaifeng county, of Henan Province. Hence, it is necessary to enhance epidemiological survey to identify risk factors at the earlier stages.


Asunto(s)
Neoplasias/mortalidad , China/epidemiología , Certificado de Defunción , Femenino , Humanos , Masculino , Mortalidad/tendencias , Población Rural
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