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The role of C-type natriuretic peptide in rat testes during spermatogenesis 被引量:7
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作者 Dong-Hui Huang Shi-Wei Zhang +1 位作者 Hu Zhao Ling Zhang 《Asian Journal of Andrology》 SCIE CAS CSCD 2011年第2期275-280,共6页
C-type natriuretic peptide (CNP) is a 22-amino acid peptide and act as a local paracrine or autocrine regulator. There is growing evidence that ChIP is involved in male reproductive processes. To investigate the rol... C-type natriuretic peptide (CNP) is a 22-amino acid peptide and act as a local paracrine or autocrine regulator. There is growing evidence that ChIP is involved in male reproductive processes. To investigate the role of CNPduring spermatogenesis, we measured the mRNA expression of CNPand its specific membrane-bound natriuretic peptide receptor-B (NPR-B) using real-time RT-PCR in the testes of normal rats on different postnatal days. After that spermatogenesis dysfunction model induced by ornidazole was established with the aim to study the correlation of CNPwith spermatogenic dysfunction. Then, Sertoli cells from 18- to 22-day-old healthy male rats were cultured in the presence of different CNPconcentrations (1 ×10-6, 1×10-7 and1×10-8 mol l-1), and the mRNA expression levels of androgen.binding protein, inhibin B and transferrin were examined at 0 min, 30 min, 1 h, 2 h, 4 h, 8 h, 12 h, 24 h and 48 h. During the postnatal development of rat testes, the highest mRNA expression levels of CNPand NPR-B were found at postnatal Do, and the levels then declined gradually, with a second ChIPpeak at postnatal D35. In the ornidazole-induced infertile rat testes, CIVPgene expression was lower than in the uninduced rats (P〈0.05), while IVPR-Bgene expression was greater (P〈0.05). In cultured Sertoli cells, supplementation with CNP stimulated the gene expression of androgen-binding pmteirginhibin B/transferrin, particularly at 12 h, and 1× 10-7 mol l-1 CNP had the highest upregulation effect. The gene expression levels of CNPIIVPR-B in rat testes at different postnatal stages and in infertile rat testes indicated that CNP may participate in the physiology and/or pathology related to spermatogenesis. Moreover, ChIP regulated endocrine function in Sertoli cells. Taken together, these results showed that CNP is closely tied to spermatogenesis. 展开更多
关键词 c-type natriuretic peptide natriuretic peptide receptor-B Sertoli cell culture SPERMATOGENESIS
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On Nonlinear Evolution of C-type Instability in Nonparallel Boundary Layers 被引量:5
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作者 Liu Jixue Tang Dengbin YangYingzhao 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2007年第4期313-319,共7页
The process of evolution, especially that of nonlinear evolution, of C-type instability of laminar-turbulent flow transition in nonparallel boundary layers are studied by means of a newly developed method called parab... The process of evolution, especially that of nonlinear evolution, of C-type instability of laminar-turbulent flow transition in nonparallel boundary layers are studied by means of a newly developed method called parabolic stability equations (PSE). Initial conditions, which are very important for the nonlinear problem, are investigated by computing initial solution of the harmonic waves, modifying the mean-flow-distortion, and giving initial value of TS wave and its subharmonic waves at initial station by solving linear PSE. A numerical method with high-order accuracy are developed in the text, the key normalization conditions in the PSE are satisfied, and nonlinear PSE are solved efficiently and implemented stably by the spatial marching. It has been shown that the computed process of nonlinear evolution of C-type instability in Blasius boundary layer is in good agreement with the experimental results. 展开更多
关键词 c-type instability nonlinear evolution nonparallelism boundary layer stability parabolic stability equations
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Functional identification of C-type lectin in the diamondback moth,Plutella xylostella(L.)innate immunity 被引量:1
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作者 LI Jin-yang LIN Jun-han +3 位作者 G.Mandela FERNANDEZ-GRANDON ZHANG Jia-yu YOU Min-sheng XIA Xiao-feng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第12期3240-3255,共16页
C-type lectins(CTLs)are a superfamily of Ca^(2+)-dependent carbohydrate-recognition proteins,and an important pattern recognition receptor(PRR)in insect innate immunity which can mediate humoral and cellular immunity ... C-type lectins(CTLs)are a superfamily of Ca^(2+)-dependent carbohydrate-recognition proteins,and an important pattern recognition receptor(PRR)in insect innate immunity which can mediate humoral and cellular immunity in insects.In this study,we report a novel dual carbohydrate-recognition domain(CRD)CTL from Plutella xylostella which we designate PxIML.PxIML is a protein with a 969 bp open reading frame(ORF)encoding 322 amino acids,containing a signal peptide and a dual-CRD with EPN(Glu_(124)-Pro_(125)-Asn_(126))and QPD(Gln_(274)-Pro_(275)-Asp_(276))motifs.The expression of PxIML mRNA in the fat body was significantly higher than in hemocytes and midgut.The relative expression levels of PxIML in the whole insect and the fat body were significantly inhibited after infection with Bacillus thuringiensis 8010(Bt8010)at 18 h,while they were significantly upregulated after infection with Serratia marcescens IAE6 or Pichia pastoris.The recombinant PxIML(rPxIML)protein could bind to the tested pathogen-associated molecular patterns(PAMPs),and the bacteria of Enterobacter sp.IAE5,S.marcescens IAE6,Staphylococcus aureus,Escherichia coli BL21,and Bt8010 in a Ca^(2+)-dependent manner,however,it showed limited binding to the fungus,P.pastoris.The rPxIML exhibited strong activity in the presence of Ca^(2+) to agglutinate Bt8010,Enterobacter sp.IAE5 and S.aureus,but it only weakly agglutinated with E.coli BL21,and could not agglutinate with S.marcescens IAE6 or P.pastoris.Furthermore,the rPxIML could bind to hemocytes,promote the adsorption of hemocytes to beads,and enhance the phenoloxidase(PO)activity and melanization of P.xylostella.Our results suggest that PxIML plays an important role in pathogen recognition and in mediating subsequent humoral and cellular immunity of P.xylostella. 展开更多
关键词 diamondback moth humoral and cellular immunity c-type lectin pattern recognition receptors carbohydrate-recognition domain
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Molecular characterization and expression analysis of a novel dual-CRD C-type lectin in kuruma shrimp(Marsupenaeus japonicus) 被引量:1
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作者 ZHANG Man MAO Yong +3 位作者 WANG Jun FENG Wenrong SONG Xiaohong SU Yongquan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第2期74-83,共10页
C-type lectins are among the most significant pattern recognition receptors(PRRs) found in invertebrate. They are a class of carbohydrate-binding proteins that can recognize specific sugar moieties on the surface of... C-type lectins are among the most significant pattern recognition receptors(PRRs) found in invertebrate. They are a class of carbohydrate-binding proteins that can recognize specific sugar moieties on the surface of pathogens. In the present study, a novel C-type lecitn(termed Mj Lectin) from kuruma shrimp Marsupenaeus japonicus was identified. The full-length c DNA of Mj Lectin was 1 245 bp with a 1 011 bp open reading frame(ORF) that encoded a polypeptide of 336 amino acid residues. Mj Lectin consisted of two tandemly arrayed carbohydrate-recognition domains(CRDs), unlike other reported M. japonicus C-type lectins with only one CRD. It showed a high similarity to other shrimp dual-CRD lectins. Among the Ca2+-binding Site 2, the tripeptide motif dictating the carbohydrate binding specificity was exhibited as a rare mutant LPN(Leu134-Pro135-Asn136) in CRD1 and a traditional EPN(Glu299-Pro300-Asn301) in CRD2, respectively. Mj Lectin showed a specific expression pattern in both tissue and cellular levels, for its m RNA transcript was mainly expressed in the F-cells of the hepatopancreas. After white spot syndrome virus(WSSV) challenge(3.6×108 virions/μL), the expression of Mj Lectin in the hepatopancreas was up-regulated significantly at 48 h(P〈0.01) compared with the control group. These results suggested that Mj Lectin might be involved in the innate immune defense against WSSV infection. 展开更多
关键词 c-type lectin Marsupenaeus japonicus carbohydrate-recognition domain(CRD) gene expression white spot syndrome virus(WSSV)
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Blending Basic Shapes By C-Type Splines and Subdivision Scheme
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作者 Xiang Li Mei-E Fang Qian Qi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2019年第7期45-62,共18页
In this article,we adopt the C-type spline of degree 2 to model and blend basic shapes including conics and circle arcs.The C-type spline belongs to theωB-spline category of splines that are capable of blending polyn... In this article,we adopt the C-type spline of degree 2 to model and blend basic shapes including conics and circle arcs.The C-type spline belongs to theωB-spline category of splines that are capable of blending polynomial,trigonometric and hyperbolic functions.Commonly used basic shapes can be exactly represented by these types of splines.We derive explicit formulas for the convenience of modeling the basic curves.The entire blending curve is C^1-continuous.In comparison with the existing best blending method by rational G^2 splines,which are rational splines of degree 3,the proposed method allows simpler representation and blending of the basic curves,and it can represent numerous basic shapes including the hyperbolic types.We also design a subdivision method to generate blending curves;this method is precise for the basic curves and approximate for the blending sections.The subdivision process is efficient for modeling and rendering.It has also proven to be C^1-continuous by the asymptotically equivalent theory and the continuity of stationary subdivision method.In addition,we extend the proposed methods to cases involving the modeling and blending of basic surfaces.We provide many examples that illustrate the merits of our methods. 展开更多
关键词 Basic SHAPES BLENDING c-type splines SUBDIVISION C^1-continuous
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Characterization and comparison of two C-type lectins with novel key motifs from mud crab Scylla paramamosain
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作者 Boxin ZENG Taiwei DONG +3 位作者 Yanting XIA Shun YANG Mengmeng HUANG Hui FEI 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2022年第4期1628-1639,共12页
As an important pattern recognition receptor(PRR)in the innate immune system,C-type lectin plays an important role in the innate immune process of invertebrates.Two C-type lectins Sp CTL-C and Sp CTL-D were characteri... As an important pattern recognition receptor(PRR)in the innate immune system,C-type lectin plays an important role in the innate immune process of invertebrates.Two C-type lectins Sp CTL-C and Sp CTL-D were characterized from mud crab(Scylla paramamosain).The predicted Sp CTL-C and Sp CTL-D proteins both contain a single carbohydrate-recognition domain(CRD)with key motif Gln-Pro-Ala(QPA)and Met-Pro-Ala(MPA),respectively.Sp CTL-C and Sp CTL-D transcripts distributed in all examined tissues,and the expression level was the highest in hepatopancreas.As PRR,the purifi ed recombinant proteins r Sp CTL-C and r Sp CTL-D have high affi nity for three kinds of pathogen-associated molecular patterns(PAMPs):β-glucan,lipopolysaccharide,and peptidoglycan.Besides,r Sp CTL-D can bind to all nine microorganisms tested,while r Sp CTL-C can bind to seven microorganisms except for Staphylococcus aureus and Micrococcus luteus.Both r Sp CTL-C and r Sp CTL-D showed agglutination activity towards fungi Pichia pastoris and Saccharomyces cerevisiae.However,r Sp CTL-C and r Sp CTL-D exhibited diff erent antimicrobial activities:r Sp CTL-D has a certain inhibitory eff ect on the growth of Vibrio fl uvialis and M.luteus,while r Sp CTL-C has no obvious inhibitory activity.The results show that r Sp CTL-C and r Sp CTL-D had better phagocytosis-promoting eff ect on M.luteus than the negative control.Meanwhile,both r Sp CTL-C and r Sp CTL-D had certain encapsulation-promoting activity.Collectively,two C-type lectins with novel key motifs make an important impact as PRR in immune response towards pathogens.At the same time,they play diff erent functions in the innate immunity of mud crab S.paramamosain. 展开更多
关键词 Scylla paramamosain immune response innate immunity c-type lectin
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Forskolin Modulates the Inhibitory Effect of C-Type Natriuretic Peptide on Hypoxia-Induced Atrial Dynamics and Hypoxia Inducible Factor 1 Alpha Activity
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作者 Chengming Guan Yanan Jia +3 位作者 Chaochao Bian Bo Zhang Dazhi Ding Xun Cui 《Journal of Biosciences and Medicines》 2017年第1期1-10,共10页
Our study investigated effects of C-type natriuretic peptide (CNP) on atrial dynamics and hypoxia inducible factor 1 alpha (HIF-1α) activity in perfused beating rat atria, under hypoxic conditions. Hypoxia significan... Our study investigated effects of C-type natriuretic peptide (CNP) on atrial dynamics and hypoxia inducible factor 1 alpha (HIF-1α) activity in perfused beating rat atria, under hypoxic conditions. Hypoxia significantly increased the levels of HIF-1α, concomitant with decreased trial dynamics. CNP (0.1 μmol/L) further decreased atrial dynamics under hypoxia and suppressed hypoxia-induced stimulation of HIF-1α expression. An adenylylcyclase (AC) activator, forskolin (0.1 μmol/L), significantly up-regulated atrial phosphodiesterase subtype 3A (PDE 3A) protein without affecting hypoxia-induced dynamics. In the presence of forskolin, the inhibitory effects of CNP on hypoxia-induced atrial dynamics and HIF-1α levels were significantly attenuated. Forskolin also prevented hypoxia-induced downregulation of PDE3A protein. These findings suggested that CNP inhibited atrial dynamics and HIF-1α activity in the isolated perfused beating rat atria under hypoxic conditions. Furthermore, both effects were modulated by the AC activator forskolin, through activation of CNP-PDE 3A signaling. 展开更多
关键词 c-type NATRIURETIC Peptide HYPOXIA INDUCIBLE Factor-1α PHOSPHODIESTERASE Adenylyl CYCLASE FORSKOLIN
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Seasonal modulation of the C-type lectin MGL on human DCs
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作者 Ilaria Grazia Zizzari Chiara Napoletano +2 位作者 Aurelia Rughetti Hassan Rahimi Marianna Nuti 《Open Journal of Immunology》 2013年第4期218-220,共3页
The C-type lectin MGL is a pathogen recognition receptor, expressed by dendritic cells (DCs) and macrophages (Mfs), able to bind GalNAc (Tn) carrying structures. This receptor also recognized Tn-TAAs that were interna... The C-type lectin MGL is a pathogen recognition receptor, expressed by dendritic cells (DCs) and macrophages (Mfs), able to bind GalNAc (Tn) carrying structures. This receptor also recognized Tn-TAAs that were internalized, processed and presented by DCs to T cells and it acted as an adjuvant on DCs, highlighting its possible application in anti-cancer vaccination. In this work, we found that this receptor present a seasonal modulation: its expression is higher in winter rather than in summer. The percentage of MGL+ donors displayed a negative trend that dropped to 33% during the summer and increased up to 100% in winter. This modulation could be also ascribed to the circa-annual variation of glucocorticoids, in fact MGL is up-regulated in presence of dexamethasone in vitro. The seasonal variation of this receptor could be an important point in the field of tumor vaccination strategies. 展开更多
关键词 MGL DENDRITIC CELLS c-type LECTIN
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Direct Decomposition of NO into N<sub>2</sub>and O<sub>2</sub>Over C-type Cubic Y<sub>2</sub>O<sub>3</sub>-Tb<sub>4</sub>O<sub>7</sub>-ZrO<sub>2</sub>
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作者 Toshiyuki Masui Shunji Uejima +1 位作者 Soichiro Tsujimoto Nobuhito Imanaka 《Materials Sciences and Applications》 2012年第10期733-738,共6页
Catalytic activities for direct NO decomposition were investigated over C-type cubic Y2O3–Tb4O7–ZrO2 prepared by a coprecipitation method. The NO decomposition activity was enhanced by partial substitution of the yt... Catalytic activities for direct NO decomposition were investigated over C-type cubic Y2O3–Tb4O7–ZrO2 prepared by a coprecipitation method. The NO decomposition activity was enhanced by partial substitution of the yttrium sites with terbium in a (Y0.97Zr0.03)2O3.03 catalyst, which shows high NO decomposition activity. Among the catalysts synthesized in this study, the (Y0.67Tb0.30Zr0.03)2O3.33 catalyst exhibited the highest NO decomposition activity;NO conversion to N2 was as high as 67% at 900℃ in the absence of O2 (NO/He atmosphere), and a relatively high conversion ratio was observed even in the presence of O2 or CO2, compared with those obtained over conventional direct NO decomposition catalysts. These results indicate that the C-type cubic Y2O3–Tb4O7–ZrO2 catalyst is a new potential candidate for direct NO decomposition. 展开更多
关键词 Nitrogen Monoxide Direct Decomposition Catalyst Rare Earth Oxide c-type CUBIC Structure
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Effects of Glutamic Acid on C-type Inactivation of Kv1.4ΔN Channel
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作者 叶琤 李晓艳 +1 位作者 舒周伍 蒋学俊 《South China Journal of Cardiology》 CAS 2008年第1期39-43,共5页
Objectives Acidosis has an inhibitory effect on the inactivation of Kv1.4 ΔN channel through the position H508. So in order to show the effects of glutamic acid on the mutant Kv 1.4 channel that lacks N-type inactiva... Objectives Acidosis has an inhibitory effect on the inactivation of Kv1.4 ΔN channel through the position H508. So in order to show the effects of glutamic acid on the mutant Kv 1.4 channel that lacks N-type inactivation (Kv1.4 Δ2-146), we studied in the expression system of the Xenopus oocytes. Methods The two-electrode voltage-clamp technique (TEV) was used to record the currents. Results Acidosis increased fKv1.4 Δ2-146 C-type inactivation. After application of glutamic acid (1 mmol/L) to Kv1.4 Δ2-146 increased C-type inactivation further, changed inactivation time constants from (2.02 ± 0.39 s ) to (1.71 ± 0.23 s) (P〈 0.05) at +50mv, and shifted the steady-state inactivation curves of Kv1.4 ΔN to positive potential, which was from (-44.30 ± 0.59 mV) to (-39.88 ± 0.29 mV)(P〈0.05). and slowed the rate of recovery from inactivation, which was from (1.64 ± 0.19 s) to (1.91 ± 0.23 s)(P〈 0.05). Conclusions Together, these results suggest that 1 mmol/L glutamic acid accelerates the C-type inactivation of Kv1.4 ΔN in pH 6.8. 展开更多
关键词 glutamic acid Kv1.4ΔN c-type inactivation xenopus oocytes
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MORPHOLOGICAL SURVEY ON ENDOGENOUS C-TYPE VIRUSES INFECTING A HUMAN LUNG SQUAMOUS CARCINOMA PASSAGED IN NUDE MICE
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作者 戴志强 张素胤 +4 位作者 许建一 俞月桂 袁幸菊 胥彬 林震琼 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1989年第4期18-21,共4页
A human lung squamous carcinoma was transplanted and passaged in Swiss-DF nude mice, called LSX-83, for more than five years in our laboratory. The morphological characteristics of the original tumor were maintained i... A human lung squamous carcinoma was transplanted and passaged in Swiss-DF nude mice, called LSX-83, for more than five years in our laboratory. The morphological characteristics of the original tumor were maintained in passages from 4 to 33. But from the 35th generation, an increasing amount of tonofilaments and nuclear segregation with typical features was found with electron microscopy. The C-type virus particles were first detected in extra cellular space after 40 passages. The viruses were observed in different stages of growth, but their distribution and number did not show apparent change up to 54 passages. Such findings suggest that LSX-83 cells probably possess certain barrier of resistance against C-type viruses. The relation between C-type viruses and the morphological changes of LSX-83 cells was discussed. 展开更多
关键词 MORPHOLOGICAL SURVEY ON ENDOGENOUS c-type VIRUSES INFECTING A HUMAN LUNG SQUAMOUS CARCINOMA PASSAGED IN NUDE MICE
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Identification of a novel C-type lectin from the shrimp Litopenaeus vannamei and its role in defense against pathogens infection 被引量:1
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作者 罗展 张继泉 +3 位作者 李富花 张晓军 柳承璋 相建海 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第5期942-951,共10页
Acting as one of the pattern recognition receptors (PRRs), C-type lectin is believed to mediate pathogen recognition and plays an important role in the clearance of pathogens as part of the innate immune system. In th... Acting as one of the pattern recognition receptors (PRRs), C-type lectin is believed to mediate pathogen recognition and plays an important role in the clearance of pathogens as part of the innate immune system. In this work, a novel C-type lectin gene (named LvLec1) was cloned from the shrimp Litopenaeus vannamei. The ORF of LvLec1 is 510 bp, encoding 169 amino acids. The deduced amino acid sequence contains a putative signal peptide of 19 amino acids at the N-terminal and a carbohydrate recognition domain (CRD) at the C-terminal. LvLec1 was mainly expressed in the hepatopancreas. Real-time PCR analysis indicated that the level of LvLec1 transcripts significantly changed in the hepatopancreas after the shrimp were artificially challenged with LPS, Micrococcus lysodeikticus and white spot syndrome virus (WSSV). RNAi-based silencing of LvLec1 resulted in increases in mortality when the shrimp were challenged with WSSV, and the median lethal time was reduced compared with controls. Although there was no characteristic "EPN" (Glu-Pro-Ser) or "QPD" (Gln-Pro-Asp) motif, the recombinant LvLec1, expressed in Escherichia coli BL21 (DE3), could also agglutinate M. lysodeikticus and Vibrio anguillarum. The agglutinating activities were calcium-dependent and could be inhibited by D-mannose, D-glucose, D-galactose and N-Acetyl-D-mannose. These results suggest that LvLec1 might be involved in the immune response against WSSV and bacterial infections and contribute to non-self recognition as a pattern recognition receptor in the innate immune system of the shrimp L. vannamei. 展开更多
关键词 南美白对虾 C型凝集素 病原体 白斑综合症病毒 感染源 氨基酸序列 模式识别 碳水化合物
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C-TYPE NATRIURETIC PEPTIDE INHIBITS UPREGULATION OF α1-ADRENOCEPTOR AND INOSITOL 1,4,5-TRISPHOSPHATE RECEPTOR IN RAT VASCULAR SMOOTH MUSCLE AFTER VASCULAR ENDOTHELIAL INJURY
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作者 王晓红 杨军 +3 位作者 佟利家 苏静怡 唐朝枢 刘乃奎 《Chinese Medical Sciences Journal》 CAS CSCD 2000年第2期73-78,共6页
Objective.In a model of balloon injury of rat aortic endothelium, the effects of C-type natriuretic peptide(CNP) on α 1-adrenoreceptor and inositol 1,4,5-triphosphate (IP 3) receptor were studied Methods. Aortic inju... Objective.In a model of balloon injury of rat aortic endothelium, the effects of C-type natriuretic peptide(CNP) on α 1-adrenoreceptor and inositol 1,4,5-triphosphate (IP 3) receptor were studied Methods. Aortic injuries were produced by vascular endothelium-denudation.α 1- adrenoreceptor in smooth muscle sarcolemma and IP 3 receptor in smooth muscle sarcoplasmic reticulum in the rat aorta were assayed by radioactive analysis method Results. It was found that neointima was formed and the contents of DNA, collagen and elastin of each intimamedia were significantly increased in 7 days and 21 days after balloon injury of rat aorta. α 1adrenoreceptor in smooth muscle sarcolemma and IP 3 receptor in sarcoplasmic reticulum were also upregulated. Results also showed that the administration of CNP ip significantly decreased the contents of DNA, collagen and elastin of each intimamedia, and inhibited the upregulation of α 1adrenoreceptor and IP 3 receptor Conclusion. The inhibition of the upregulation of α 1adrenoreceptor and IP 3 receptor by CNP might be one of the mechanisms of its suppressive action on intimal 展开更多
关键词 CNP IP3 al-肾上腺素受体 IP3受体 血管平滑肌 血管内皮损伤
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The in situ spectral methods for examining redox status of c-type cytochromes in metal-reducing/oxidizing bacteria
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作者 Xiaobo Luo Yundang Wu +4 位作者 Xiaomin Li Dandan Chen Ying Wang Fangbai Li Tongxu Liu 《Acta Geochimica》 EI CAS CSCD 2017年第3期544-547,共4页
The membrane-associated c-type cytochromes(c-Cyts) have been well known as the key enzymes mediating extracellular electron transfer to terminal electron acceptors, resulting in biogeochemical elemental transformation... The membrane-associated c-type cytochromes(c-Cyts) have been well known as the key enzymes mediating extracellular electron transfer to terminal electron acceptors, resulting in biogeochemical elemental transformation, contaminant degradation, and nutrient cycling. Although c-Cyts-mediated metal reduction or oxidation have been mainly investigated with the purified proteins of metal reducing/oxidizing bacteria, the in vivo behavior of c-Cyts is still unclear, given the difficulty in measuring the proteins of intact cells. Fortunately, the in situ spectroscopy would be ideal for measuring the reaction kinetics of c-Cyts in intact cells under noninvasive physiological conditions. It can also help the establishment of kinetic/thermodynamic models of extracellular electron transfer processes, which are essential to understand the electron transfer mechanisms at the molecular scale. This review briefly summarizes the current advances in spectral methods for examining the c-Cyts in intact cells of dissimilatory metal reducing bacteria and Fe(Ⅱ)-oxidizing bacteria. 展开更多
关键词 氧化还原状态 细胞色素 金属氧化 原位光谱 谱方法 细菌 c型 异化金属还原菌
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Alternation of plasma c-type natriuretic peptide in cerebral infarction
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作者 赵文凤 宋利春 《中国临床康复》 CSCD 2003年第1期138-138,共1页
AIM:To investigate the effects of c type natriuretic peptide (CNP) on cerebral infarction.METHODS:Plasma levels of CNP were concomitantly measured by radioimmunoassay in 30 patients with cerebral infarction and in 30 ... AIM:To investigate the effects of c type natriuretic peptide (CNP) on cerebral infarction.METHODS:Plasma levels of CNP were concomitantly measured by radioimmunoassay in 30 patients with cerebral infarction and in 30 normal controls.RESULTS:Plasma levels of CNP were increased significantly in the acute stage of cerebral infarction than those in the normal controls(P< 0.01) and levels in the moderate and serious cases were lower than those in the slight cases(P< 0.01).CONCLUSION:In cerebral infarction the increase of plasma CNP was in accordance with the severity of the disease .CNP in the pathophysiology of acute cerebral ischemia had a deleterious effect on the evolution of cerebral infarction. 展开更多
关键词 脑梗死 血浆 C型利钠肽
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Tinker,tailor,soldier,cell:the role of C-type lectins in the defense and promotion of disease 被引量:1
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作者 James N.Arnold Daniel A.Mitchell 《Protein & Cell》 SCIE CSCD 2023年第1期4-16,共13页
C-type lectins(CTLs)represent a large family of soluble and membrane-bound proteins which bind calcium dependently via carbohydrate recognition domains(CRDs)to glycan residues presented on the surface of a variety of ... C-type lectins(CTLs)represent a large family of soluble and membrane-bound proteins which bind calcium dependently via carbohydrate recognition domains(CRDs)to glycan residues presented on the surface of a variety of pathogens.The deconvolution of a cell’s glycan code by CTLs underpins several important physiological processes in mammals such as pathogen neutralization and opsonization,leukocyte trafficking,and the inflammatory response.However,as our knowledge of CTLs has developed it has become apparent that the role of this innate immune family of proteins can be double-edged,where some pathogens have developed approaches to subvert and exploit CTL interactions to promote infection and sustain the pathological state.Equally,CTL interactions with host glycoproteins can contribute to inflammatory diseases such as arthritis and cancer whereby,in certain contexts,they exacerbate inflammation and drive malignant progression.This review discusses the‘dual agent’roles of some of the major mammalian CTLs in both resolving and promoting infection,inflammation and inflammatory disease and highlights opportunities and emerging approaches for their therapeutic modulation. 展开更多
关键词 c-type lectins DC-SIGN MBL SELECTINS infection ARTHRITIS cancer
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A pattern recognition receptor C-type lectin TcCTL14 contributes to immune response and development in the red flour beetle, Tribolium castaneum
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作者 Yonglei Zhang Huayi Ai +6 位作者 Yihan Wang Ping Zhang Liheng Du Jiatao Wang Suisui Wang Han Gao Bin Li 《Insect Science》 SCIE CAS CSCD 2023年第5期1363-1377,共15页
Evidence is accumulating that pattern recognition receptor(PRR)C-type lectins(CTL)play essential roles in recognition of pathogens.TcCTL14(accession no.TC00871)contains the most domains among all CTL of Tribolium cast... Evidence is accumulating that pattern recognition receptor(PRR)C-type lectins(CTL)play essential roles in recognition of pathogens.TcCTL14(accession no.TC00871)contains the most domains among all CTL of Tribolium castaneum.Yet the biological function of TcCTL14 remains unclear.In this study,TcCTL14 exhibiting typical motif and domain of CTL was cloned from T.castaneum.The expression pattern analysis showed that TcCTL14 was highly expressed in late pupae and central nervous system,and was upregulated after treatment with Escherichia coli and Staphylococcus aureus,respectively.Analysis of binding affinity revealed that recombinant TcCTL14 not only could bind to lipopolysaccharide and peptidoglycan in a dose-dependent fashion,but possibly could bind to and agglutinate different bacteria in a Ca^(2+)-dependent fashion.Knockdown of TcCTL14 before injection with bacteria led to the downregulation of nuclear factor-κB transcription factors of Toll/IMD and 4 antimicrobial peptides.Knockdown of TcCTL14 also caused suppressed metamorphosis,reduced fecundity,and delayed embryogenesis of T.castaneum.Further observation discovered that knockdown of TcCTL14 inhibited the development of ovaries and embryos.The detection of signaling pathways revealed that TcCTL14 may be involved in metamorphosis and fecundity by impacting 20-hydroxyecdysone and vitellogenin,respectively.Overall,these results indicate that TcCTL14 may contribute to immune response by agglutination or regulating the expression of antimicrobial peptides by the Toll/IMD pathway,and is required for T.castaneum development including metamorphosis,fecundity,and embryogenesis.These findings will improve the functional cognition of PRR CTL in insects and provide the new strategy for pest control. 展开更多
关键词 c-type lectins EMBRYOGENESIS FECUNDITY immune response metamorpho-sis Tribolium castaneum
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2020年全国医院感染监控网丙型肝炎病毒感染监测报告
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作者 文细毛 任南 +12 位作者 李福琴 战榕 方旭 孟庆兰 杨怀 李卫光 刘丁 郭凤玲 鲜于舒铭 赖晓全 逄崇杰 黄勋 吴安华 《中国感染控制杂志》 CAS CSCD 北大核心 2024年第1期1-8,共8页
目的了解医疗机构住院患者丙型肝炎病毒(HCV)感染情况及变化趋势,为制定HCV感染防控策略提供参考依据。方法对2020年上报至全国医院感染监控网医院感染横断面调查资料中HCV感染监测结果进行汇总分析,HCV阳性为血清抗-HCV阳性或HCV RNA阳... 目的了解医疗机构住院患者丙型肝炎病毒(HCV)感染情况及变化趋势,为制定HCV感染防控策略提供参考依据。方法对2020年上报至全国医院感染监控网医院感染横断面调查资料中HCV感染监测结果进行汇总分析,HCV阳性为血清抗-HCV阳性或HCV RNA阳性,并与2003年调查结果进行比较。结果2020年1573所医院调查住院患者1071368例,其中738535例患者进行了HCV相关检测,4014例存在HCV感染,检测率为68.93%,HCV阳性率为0.54%。男性患者HCV阳性率为0.60%,女性患者为0.48%,两者比较差异有统计学意义(χ^(2)=47.18,P<0.001)。年龄段以50~<60岁组HCV阳性率最高(0.76%),其次为40~<50岁组,HCV阳性率为0.71%,各年龄段比较差异有统计学意义(χ^(2)=696.74,P<0.001)。2003年调查住院患者91113例,35145例进行HCV相关检测,检测率为38.57%,775例存在HCV感染,HCV阳性率为2.21%。2020年不同规模医院HCV阳性率为0.46%~0.63%,以医院床位数600~899张者最高,不同规模医院患者HCV阳性率比较,差异有统计学意义(χ^(2)=35.34,P<0.001)。2020年有12个省/直辖市/自治区HCV相关检测患者人数>10000例,HCV阳性率为0.19%~0.81%,以海南省最高;不同科室HCV阳性率为0.06%~0.82%,以儿科HCV阳性率最低,内科HCV阳性率最高。2003、2020年HCV阳性率均以感染病科最高,分别为7.95%、3.48%,2003年其次为整形科(7.72%)、消化科(3.77%)、肾病科(3.57%)、综合重症监护病房(ICU,3.10%),2020年其次为消化科(1.35%)、肾病科(1.18%)、内分泌科(0.91%)、综合ICU(0.79%)。结论与2003年相比,2020年HCV阳性率明显下降。HCV感染患者主要分布在感染病科,其次为消化科、肾病科及综合ICU,HCV感染阳性率存在性别、年龄、地域的差异。 展开更多
关键词 肝炎病毒 丙型 丙型肝炎病毒 流行病学调查 住院患者 发病率
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HbA1c、LDL-C、HDL-C联合检测在2型糖尿病肾病中的诊断价值 被引量:1
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作者 李婷婷 张媚琰 《中外医学研究》 2024年第4期67-71,共5页
目的:探究糖化血红蛋白(HbA1c)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)联合检测在2型糖尿病肾病中的诊断价值。方法:选取2019年1月—2021年12月南京中医药大学附属苏州市中医医院收治的120例2型糖尿病患者作为研究对... 目的:探究糖化血红蛋白(HbA1c)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)联合检测在2型糖尿病肾病中的诊断价值。方法:选取2019年1月—2021年12月南京中医药大学附属苏州市中医医院收治的120例2型糖尿病患者作为研究对象。根据患者是否发生糖尿病肾病将其分为合并肾病组(n=35)和未合并肾病组(n=85)。收集两组患者一般资料。检测两组Hb A1c、LDL-C、HDL-C。比较两组一般资料及Hb A1c、LDL-C、HDL-C水平。分析2型糖尿病肾病的危险因素。分析HbA1c、LDL-C、HDL-C对2型糖尿病肾病的诊断价值。结果:合并肾病组糖尿病病程长于未合并肾病组,吸烟史占比高于未合并肾病组,差异有统计学意义(P<0.05)。合并肾病组HbA1c、LDL-C水平均高于未合并肾病组,HDL-C水平低于未合并肾病组,差异有统计学意义(P<0.05)。logistic分析结果显示,HbA1c、LDL-C、吸烟史、糖尿病病程均是2型糖尿病患者合并糖尿病肾病的危险因素,HDL-C是保护因素(P<0.05)。HbA1c、LDL-C、HDL-C联合检测的AUC最高。结论:HbA1c、LDL-C、HDL-C联合检测应用于2型糖尿病肾病诊断中,具有较高的诊断价值,为临床对2型糖尿病肾病的早期诊断提供新思路。 展开更多
关键词 糖化血红蛋白 低密度脂蛋白胆固醇 高密度脂蛋白胆固醇 联合检测 2型糖尿病肾病 危险因素
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解剖锁定钛板及桡侧阻挡钛板治疗桡骨远端C型骨折的疗效
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作者 王鑫 吴宏伟 +5 位作者 陶晶 唐永冬 秦秋 孙路 刘博 何斌 《临床骨科杂志》 2024年第2期230-233,共4页
目的探讨解剖锁定钛板及桡侧阻挡钛板治疗桡骨远端C型骨折的疗效。方法将40例桡骨远端C型骨折患者按照治疗方法不同分为观察组(采用解剖锁定钛板及桡侧阻挡钛板治疗,20例)和对照组(采用单纯桡骨远端解剖锁定钛板治疗,20例)。记录两组术... 目的探讨解剖锁定钛板及桡侧阻挡钛板治疗桡骨远端C型骨折的疗效。方法将40例桡骨远端C型骨折患者按照治疗方法不同分为观察组(采用解剖锁定钛板及桡侧阻挡钛板治疗,20例)和对照组(采用单纯桡骨远端解剖锁定钛板治疗,20例)。记录两组术中骨折复位情况、术中出血量、手术时间、骨折愈合情况、掌倾角、尺偏角及腕关节活动度。结果患者均获得随访,时间2.5~6个月。术中观察组骨折断端均固定良好,对位对线满意,无桡侧骨块移位;对照组9例骨折复位及固定满意,11例存在不同程度的桡侧骨块移位。术中出血量、手术时间两组比较差异均无统计学意义(P>0.05)。两组骨折均愈合,时间10~12周。末次随访时,两组掌倾角比较差异无统计学意义(P>0.05);尺偏角及腕关节掌屈、背伸活动度观察组均大于对照组(P<0.05)。结论解剖锁定钛板及桡侧阻挡钛板治疗桡骨远端C型骨折,术中骨折复位简单,同时能有效减少桡侧骨块移位,更利于患者腕关节功能恢复。 展开更多
关键词 桡骨远端C型骨折 解剖锁定钛板 桡侧阻挡板
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