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1.
Zhonghua Xin Xue Guan Bing Za Zhi ; 52(6): 676-683, 2024 Jun 24.
Artigo em Chinês | MEDLINE | ID: mdl-38880747

RESUMO

Objective: To investigate the association between body composition and coronary artery calcification in patients with chronic kidney disease (CKD). Methods: This cross-sectional study enrolled patients with CKD hospitalized from May 2019 to April 2022 at Sun Yat-sen Memorial Hospital, Guangzhou, China. Skeletal muscle mass index and visceral fat area were measured by bioelectrical impedance analysis. Coronary artery calcification was assessed by computed tomography. Patients were divided into coronary artery calcification group and non-coronary artery calcification group according to the incidence of coronary artery calcification. Patients were categorized into tertile groups according to their skeletal muscle mass index and visceral fat area levels ranging from the lowest to the highest levels (T1 to T3). We defined skeletal muscle mass index≤30.4% as low muscle mass and visceral fat area≥80.6 cm2 as high visceral fat based on the results of the restricted cubic spline graph. All individuals were divided into 4 phenotypes: normal body composition, low muscle mass, high visceral fat, and low muscle mass with high visceral fat. Spearman correlation analysis and logistic regression analysis were used to assess the association between skeletal muscle mass index, visceral fat area and coronary artery calcification. Results: A total of 107 patients with CKD were enrolled, with an age of (60.0±14.1) years, including 41 female patients (38.3%). Patients of coronary artery calcification group had lower skeletal muscle mass index ((32.0±4.8) vs. (34.3±4.8), P=0.016) and higher visceral fat area ((70.8±32.6) cm2 vs. (47.9±23.8) cm2, P<0.001) than those of non-coronary artery calcification group. Patients in the T3 group of skeletal muscle mass index had a lower prevalence of coronary artery calcification (17 (48.6%) vs. 28 (77.8%)) and a lower coronary artery calcification score (0.5 (0, 124.0) vs. 12.0 (0.3, 131.0)) than those in the T1 group (P<0.05). Similarly, patients in the T1 group of visceral fat area had a lower prevalence of coronary artery calcification (14 (40.0%) vs. 29 (80.6%)) and a lower coronary artery calcification score (0 (0, 3.0) vs. 37.0 (2.0, 131.0)) than those in the T3 group (P<0.05). Likewise, patients with both low muscle mass and low muscle mass with high visceral fat had a higher prevalence of coronary artery calcification (11(78.6%) vs. 33 (47.8%); 15 (83.3%) vs. 33 (47.8%)) and a higher coronary artery calcification score (31.1 (0.8, 175.8) vs. 0 (0, 16.4); 27.6 (6.4, 211.4) vs. 0 (0, 16.4)) than those with normal body composition (P<0.05). Spearman correlation analysis showed that skeletal muscle mass index was inversely correlated with coronary artery calcification score (r=-0.212, P=0.028), and visceral fat area was positively correlated with coronary artery calcification score (r=0.408, P<0.001). Multivariate logistic regression analysis showed that increased skeletal muscle mass index was inversely associated with coronary artery calcification prevalence (T2: OR=0.208, 95%CI: 0.056-0.770, P=0.019; T3: OR=0.195, 95%CI: 0.043-0.887, P=0.034), and reduced visceral fat area was inversely associated with coronary artery calcification prevalence (T1: OR=0.256, 95%CI: 0.071-0.923, P=0.037; T2: OR=0.263, 95%CI: 0.078-0.888, P=0.031). Consistently, both low muscle mass and low muscle mass with high visceral fat were associated with coronary artery calcification prevalence (OR=6.616, 95%CI: 1.383-31.656, P=0.018; OR=5.548, 95%CI: 1.062-28.973, P=0.042). Conclusion: Reduced skeletal muscle mass index and increased visceral fat area are significantly associated with both the prevalence and severity of coronary artery calcification in patients with CKD.


Assuntos
Composição Corporal , Doença da Artéria Coronariana , Gordura Intra-Abdominal , Insuficiência Renal Crônica , Calcificação Vascular , Humanos , Estudos Transversais , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/fisiopatologia , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/fisiopatologia , Gordura Intra-Abdominal/diagnóstico por imagem , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/complicações , Calcificação Vascular/fisiopatologia , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/fisiopatologia , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/patologia , Masculino , Feminino , Pessoa de Meia-Idade
3.
Phys Rev Lett ; 124(11): 113401, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-32242719

RESUMO

We report on C^{3+}(1s2ℓ2ℓ^{'} ^{2S+1}L)-resolved cross sections of electron capture in collisions of swift C^{4+}(1s2s ^{3}S) ions with helium and hydrogen. The study focuses on the formation of doubly excited triply open-shell C^{3+}(1s2s2p) ^{4}P and ^{2}P_{±} states with emphasis on the ratio R of their cross sections as a measure of spin statistics. Using zero-degree Auger projectile spectroscopy and a three-electron close-coupling semiclassical approach, we resolve a long-standing puzzle and controversy on the value of R and on the effect of cascades, to clarify the underlying physics. The present results invalidate the frozen core approximation generally used in the past when considering electron capture in multielectron multi-open-shell quantum systems. A distinctive screening effect due to the Pauli exclusion principle (Pauli shielding) is proposed to account for the value of R, consistent with our findings.

4.
Fa Yi Xue Za Zhi ; 35(4): 467-471, 2019 Aug.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-31532159

RESUMO

ABSTRACT: The new Standardization Law, implemented in 2018, has added a standard post-implementation evaluation system, aiming to continuously improve the quality of standards through post-implementation evaluation. Standards in the forensic science field are closely related to accreditation activities. Forensic science standards are not only the criteria on which accreditation activities are carried out, but also one of the key contents of the inspection of forensic science institutions in accreditation activities. Since 2018, the certification and accreditation policies in the forensic science field have also been changed, which has brought impacts on the construction of a standard system based on accreditation.This paper analyzes the standard data from China National Accreditation Center from Conformity Assessment on forensic clinical identification accreditation assessment. It points out that the current coverage of laboratory accreditation activities is limited, the development in different provinces is unbalanced, and there is overlap and crossover in the standards in use. It is emphasized that the construction of the national forensic science standardization technical committee, the improvement of the forensic science standard system, the establishment of the standard implementation evaluation index system, and promotion of the coordination of standards, and the certifications and accreditations should be accelerated, in order to continue to promote the standardization and accreditation activities in the field of forensic science.


Assuntos
Acreditação/legislação & jurisprudência , Ciências Forenses/normas , China
5.
Phys Rev Lett ; 122(9): 093402, 2019 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-30932521

RESUMO

We have investigated the double electron capture process in the H^{+}+H^{-} collision system for energies from 60 eV to 20 keV. Despite the apparent simplicity of this highly correlated system, all previous calculations fail to reproduce the experimental total cross sections. Moreover, the latter exhibit oscillations that have been previously attributed to quantum interferences between the gerade and ungerade ionic states of the transient molecule formed during the collision. For this process, we present the absolute cross sections obtained from a fully correlated two-active-electron semiclassical atomic-orbital close-coupling approach. Our results reproduce well the experimental data in both magnitude and shape. Furthermore, we demonstrate that the oscillations stem from coherence effects between double electron capture and other two-electron inelastic channels, namely the transfer-excitation processes. This alternative interpretation is supported by a Rosenthal-like model based on a molecular treatment of the collision. Our results shed new light on this old but challenging problem.

7.
Genet Mol Res ; 14(4): 17068-78, 2015 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-26681054

RESUMO

Cumulated evidence indicates that matrix metalloproteinase-3 (MMP-3) is significantly involved in cancer progression. Recent studies yielded conflicting results regarding the association between serum MMP-3 and ankylosing spondylitis (AS). To clarify this correlation, we performed a meta-analysis. Potential relevant studies were identified by searching the following databases: PubMed, Embase, CINAHL, Science Citation Index database, the Cochrane Library, Current Contents Index, Chinese Biomedical, the Chinese Journal Full-Text, and the Weipu Journal. Data from eligible studies were extracted and included into the meta-analysis using a random-effect model. Standardized mean differences (SMDs) and 95% confidence intervals (CIs) were used to assess the association between serum MMP-3 levels and AS. Thirteen case-control studies, including 707 AS cases and 442 healthy controls, were selected for the meta-analysis. The results indicate a significantly higher serum MMP-3 level in patients with AS than that in the controls (cases vs controls: SMD = 1.31, 95%CI = 0.84-1.78, P < 0.001). Ethnicity-subgroup analysis indicated a higher MMP-3 level in Asian and Caucasian patients with AS (all P < 0.05). This meta-analysis indicates that increased serum MMP-3 level correlates with the development of AS, suggesting that MMP-3 may present a clinical value in reflecting the progression of AS. Further larger sample size studies are warranted.


Assuntos
Metaloproteinase 3 da Matriz/sangue , Espondilite Anquilosante/sangue , Biomarcadores , Estudos de Casos e Controles , Suscetibilidade a Doenças , Humanos , Viés de Publicação , Risco
8.
Eur Rev Med Pharmacol Sci ; 19(14): 2523-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26221877

RESUMO

OBJECTIVE: The purpose of this essay is to explore the treatments of caesarean scar pregnancy and the corresponding results during the past ten years. PATIENTS AND METHODS: There were 56 cases of caesarean scar pregnancy in the past ten years which were divided into two groups. Group A included 22 cases in the first five years from January 2004 to December 2008, and group B had 34 cases in the last five years from January 2009 to December 2013. Analysis and statistical treatments are performed according to the comparison of the general state, severity, therapeutic condition and results in both groups. RESULTS: We found that the operation rate of group A is lower than that of group B while the average hospitalization and follow-up time of group A are longer than that of group B. The re-hospitalization rate of group A is 22.73% (5/22) and is higher than 11.76% of group B (4/34). The vagina bleeding rate of group A is 27.27% (6/22) and is higher than 2.94% of group B (1/34). CONCLUSIONS: With the increasingly deep-rooted concept of minimally invasive technique in gynecology, minimally invasive therapy becomes increasingly popular for the treatment of caesarean scar pregnancy. The advantages include short treatment period and follow-up time and safe therapy which to some extent reduces the burden and mental pressure of patients.


Assuntos
Cesárea/efeitos adversos , Cicatriz/terapia , Metotrexato/administração & dosagem , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Complicações na Gravidez/terapia , Adulto , Cesárea/tendências , Cicatriz/diagnóstico , Cicatriz/etiologia , Terapia Combinada/métodos , Feminino , Seguimentos , Hospitalização/tendências , Humanos , Procedimentos Cirúrgicos Minimamente Invasivos/tendências , Gravidez , Complicações na Gravidez/diagnóstico , Complicações na Gravidez/etiologia , Fatores de Tempo , Resultado do Tratamento , Embolização da Artéria Uterina/métodos , Hemorragia Uterina/diagnóstico , Hemorragia Uterina/etiologia , Hemorragia Uterina/terapia
9.
Epidemiol Infect ; 143(2): 366-75, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25497741

RESUMO

Genetic association studies of the cytokine interleukin-10 (IL-10) and sepsis have provided inconsistent results. This work attempts to further quantitatively assess the association of three widely evaluated polymorphisms of IL-10 (-592C/A, -819C/T, -1082A/G) with sepsis susceptibility through a meta-analysis. A search of Pubmed, Web of Science and EMBASE databases was performed. Overall, the three polymorphisms have no strong association with sepsis risk. Subgroup analysis by ethnicity showed there was association between sepsis susceptibility with -592C/A in Caucasians (A vs. C: OR 0·78, 95% CI 0·62-1·00, P = 0·05; AA + CA vs. CC: OR 0·75, 95% CI 0·56-1·00, P = 0·05), and with -1082A/G in Asians (G vs. A: OR 1·41, 95% CI 1·04-1·91, P = 0·03; GG + AG vs. AA: OR 2·11, 95% CI 1·07-4·16, P = 0·03). This meta-analysis suggests that -592C/A and -1082A/G polymorphisms are associated with sepsis susceptibility in Caucasian, and Asian populations, respectively.


Assuntos
Predisposição Genética para Doença/genética , Interleucina-10/genética , Polimorfismo Genético/genética , Sepse/genética , Povo Asiático/genética , Humanos , População Branca/genética
10.
Epidemiol Infect ; 142(10): 2195-206, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24398289

RESUMO

Several studies have evaluated the association between mannose-binding lectin (MBL) polymorphisms and sepsis. However, the results are inconclusive and conflicting. To better understand the roles of MBL polymorphisms in sepsis, we conducted a comprehensive meta-analysis. All relevant studies were searched from PubMed, EMBASE and Web of Knowledge databases, with the last report up to 7 May 2013. Twenty-nine studies addressing four MBL polymorphisms (-550G/C, -221G/C, structure variant A/O, Gly54Asp) were analysed for susceptibility to sepsis and one study for sepsis-related mortality. Overall, significant associations between structure variant A/O and susceptibility to sepsis were observed for AO + OO vs. AA [odds ratio (OR) 1·27, 95% confidence interval (CI) 1·05-1·52, P = 0·01] and O vs. A (OR 1·19, 95% CI 1·02-1·40, P = 0·03). In subgroup analysis based on age group, increased risk was found in the paediatric group in the dominant model (OR 1·72, 95% CI 1·16-2·56, P = 0·007). Moreover, there was a slight association between the +54A/B polymorphism and susceptibility to sepsis in Caucasians (recessive model: OR 10·64, 95% CI 1·24-91·65, P = 0·03). However, no association was observed for -550G/C and -221G/C polymorphisms both overall and in subgroup analysis. For sepsis-related mortality, only one study suggested AO/OO was associated with in-hospital mortality in pneumococcal sepsis patients after controlling for confounding variables. Our meta-analysis indicated that MBL structure variants might be associated with susceptibility to sepsis but further studies with a large sample size should be conducted to confirm these findings.


Assuntos
Lectina de Ligação a Manose/genética , Polimorfismo Genético/genética , Sepse/genética , Adulto , Fatores Etários , Criança , Predisposição Genética para Doença , Humanos , Razão de Chances , Sepse/mortalidade
11.
Adv Mater ; 25(35): 4938-43, 2013 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-23857730

RESUMO

A large contrast in the electrical and thermal conductivities via a first order phase transition in surface-functionalized carbon nanotube(CNT)/hexadecane composites is reported. Surface modification of the CNTs improves the electrical conductivity contrast and the stability of the composites. We demonstrate that, with these composites, the electrical conductivity changes above 10(5) times and the thermal conductivity varies up to 3 times at 18 °C.

12.
Tissue Antigens ; 78(4): 294-5, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21623731

RESUMO

HLA-DRB1*08:41 shows seven nucleotide differences from DRB1*08:18 and result in three amino acid changes.


Assuntos
Alelos , Substituição de Aminoácidos , Cadeias HLA-DRB1/genética , Povo Asiático , China , Humanos , Doadores de Tecidos
13.
Nano Lett ; 9(12): 4128-32, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19995084

RESUMO

Heat conduction mechanisms in nanofluids, fluids seeded with nanoparticles, have been extensively scrutinized in the past decades to explain some experimental observations of their enhanced thermal conductivity beyond the effective medium theory. Although many mechanisms such as Brownian motion, clustering, ballistic transport, and internanoparticle potential are speculated, experimental proof of any of the mechanisms has been difficult. Here, we investigate the mechanisms experimentally by thermal conductivity measurements and structural analysis for the same materials in both liquid and solid states. These studies strongly suggest that clustering holds the key to the thermal conductivity enhancement of nanofluids.


Assuntos
Transferência de Energia , Temperatura Alta , Microfluídica/métodos , Modelos Teóricos , Nanoestruturas/química , Soluções/química , Simulação por Computador , Nanoestruturas/ultraestrutura , Condutividade Térmica
15.
Protein Expr Purif ; 7(2): 220-8, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8812866

RESUMO

Increasing the level of recovery of mammalian proteins secreted by a genetically modified Nicotiana tabacum was explored in suspension culture. As a model protein system, a mouse monoclonal antibody heavy chain gamma (MAb HC) with an antigen specificity for p-azophenylarsonate was used. Consistent with findings for other plant cell suspension culture systems expressing proteins with mammalian leader sequences, the synthesized mouse MAb HC was secreted through the plasma membrane. In addition, the majority of the MAb HC was also secreted through the cell wall into the growth medium. However, efficient recovery of the protein was only possible when the protein stabilizing agent, polyvinylpyrrolidone (PVP) was present in the plant cell growth medium. The presence of PVP increased the recovered concentration of secreted protein 35-fold from 0.010 to 0.36 micrograms protein/ml culture medium. Biological activity of the approximately 50-kDa MAb HC polypeptide was demonstrated by arsonate affinity matrix binding as determined by Western blot analysis. In addition to antigen binding activity, the secreted protein also exhibited reactivity to protein G, a protein which specifically binds mouse IgG. These findings are important because they demonstrate that culture conditions can significantly influence the concentration of a biologically active foreign protein secreted from plant cells into the media of suspension cultures. The ability to increase the efficiency of mammalian protein production in plant suspension culture systems should provide significant advantage over protein production in intact transgenic plants which require cultivation, harvesting, and expensive extraction procedures to obtain nonsecreted foreign proteins.


Assuntos
Anticorpos Monoclonais/genética , Cadeias Pesadas de Imunoglobulinas/genética , Nicotiana/genética , Nicotiana/metabolismo , Plantas Tóxicas , Animais , Anticorpos Monoclonais/imunologia , Baculoviridae/genética , Baculoviridae/metabolismo , Northern Blotting , Western Blotting , Fracionamento Celular , Células Cultivadas , Células Clonais/metabolismo , Regulação da Expressão Gênica/genética , Vetores Genéticos/genética , Cadeias Pesadas de Imunoglobulinas/imunologia , Camundongos , Plantas Geneticamente Modificadas/genética , Povidona/farmacologia , Ligação Proteica , Proteínas Recombinantes/isolamento & purificação , Transformação Genética/genética , p-Azobenzenoarsonato/metabolismo
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