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
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
C-type natriuretic peptide （CNP） is a newly discovered type of local regulatory factor that mediates its biological effects through the specific, membrane-bound natriuretic peptide receptor-B （NPR-B）. Recent studi...C-type natriuretic peptide （CNP） is a newly discovered type of local regulatory factor that mediates its biological effects through the specific, membrane-bound natriuretic peptide receptor-B （NPR-B）. Recent studies have established that CNP is closely related to male reproductive function. The aims of this study were to determine the distribution of CNP/NPR-B in human ejaculated spermatozoa through different methods （such as immunolocalization, real time polymerase chain reaction and Western Blot）, and then to evaluate the influence of CNP on sperm function in vitro, such as motility and acrosome reaction. Human semen samples were collected from consenting donors who met the criteria of the World Health Organization for normozoospermia. Our results show that the specific receptor NPR-B of CNP is localized in the acrosomal region of the head and the membrane of the front-end tail of the sperm, and there is no signal of CNP in human sperm. Compared with the control, CNP can induce a significant dose-dependent increase in spermatozoa motility and acrosome reaction. In summary, CNP/NPR-B can affect sperm motility and acrosome reaction, thus regulating the reproductive function of males. CNP may be a new key factor in regulating sperm function.展开更多
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 ...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 LvLecl） was cloned from the shrimp Litopenaeus vannamei, The ORF of LvLecl 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. LvLecl was mainly expressed in the hepatopancreas. Real-time PCR analysis indicated that the level of LvLecl 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 LvLecl 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＂ （Gin-Pro-Asp） motif, the recombinant LvLecl, 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 LvLecl 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
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
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
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
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
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 st...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 proliferation展开更多
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
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
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
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
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
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
目的:回顾性分析香菊胶囊联合鼓室注射地塞米松治疗慢性分泌性中耳炎(Otitis media with effusion,OME)的临床效果。方法:收集我院2023年3月至2024年3月间收治的98例慢性OME患者临床资料,按治疗方法不同分为西药组和联合组(n=49),西药...目的:回顾性分析香菊胶囊联合鼓室注射地塞米松治疗慢性分泌性中耳炎(Otitis media with effusion,OME)的临床效果。方法:收集我院2023年3月至2024年3月间收治的98例慢性OME患者临床资料,按治疗方法不同分为西药组和联合组(n=49),西药组进行鼓室注射地塞米松磷酸钠注射液0.2mL治疗,联合组加用香菊胶囊。治疗12 w后,比较两组的疗效;采用美国GSI-61听力计测试各频率的骨导阈值;酶联免疫吸附试验检测耳积液白细胞介素-8(Interleukin-8,IL-8)、白细胞介素-6(Interleukin-6,IL-6)、肿瘤坏死因子-α(Tumornecrosisfactor-α,TNF-α)水平;采用ZODIAC901型中耳分析仪分析鼓室图。结果:治疗12w后,联合组总有效率高于西药组(100.00%vs87.76%)(P<0.05);治疗12w后,联合组各频率(1,2,4,8kHz)下的骨导阈值、耳积液IL-8、IL-6、TNF-α水平均低于西药组(P<0.05);治疗12w后,联合组鼓室图各类型分布情况优于西药组(P<0.05)。结论:香菊胶囊联合鼓室注射地塞米松治疗慢性OME疗效确切,能降低骨导阈值,改善耳积液相关因子水平、鼓室图。展开更多
文摘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.
文摘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.
文摘C-type natriuretic peptide （CNP） is a newly discovered type of local regulatory factor that mediates its biological effects through the specific, membrane-bound natriuretic peptide receptor-B （NPR-B）. Recent studies have established that CNP is closely related to male reproductive function. The aims of this study were to determine the distribution of CNP/NPR-B in human ejaculated spermatozoa through different methods （such as immunolocalization, real time polymerase chain reaction and Western Blot）, and then to evaluate the influence of CNP on sperm function in vitro, such as motility and acrosome reaction. Human semen samples were collected from consenting donors who met the criteria of the World Health Organization for normozoospermia. Our results show that the specific receptor NPR-B of CNP is localized in the acrosomal region of the head and the membrane of the front-end tail of the sperm, and there is no signal of CNP in human sperm. Compared with the control, CNP can induce a significant dose-dependent increase in spermatozoa motility and acrosome reaction. In summary, CNP/NPR-B can affect sperm motility and acrosome reaction, thus regulating the reproductive function of males. CNP may be a new key factor in regulating sperm function.
基金Supported by the National Basic Research Program of China (973 Program) (No. 2006CB101804)the National Natural Science Foundation of China (No. 30972245)Public Industry (Agriculture) Specific Research Program (No. 200803012)
文摘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 LvLecl） was cloned from the shrimp Litopenaeus vannamei, The ORF of LvLecl 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. LvLecl was mainly expressed in the hepatopancreas. Real-time PCR analysis indicated that the level of LvLecl 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 LvLecl 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＂ （Gin-Pro-Asp） motif, the recombinant LvLecl, 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 LvLecl 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.
基金the project of the National Key R&D Program of China(2017YFE0122000)the National Natural Science Foundation of China(31871968)the Natural Science Foundation of Fujian Province,China(2018J01614).
文摘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.
基金The National High-Technology R&D Program(863 Program) of China under contract No.2012AA10A409China Agriculture Research System under contract No.CARS-47
文摘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.
基金This work described in this article was supported by the National Science Foundation of China(61772164,61272032)Provincial Key Platforms and Major Scientific Research Projects in Universities and Colleges of Guangdong(2017KTSCX143)the Natural Science Foundation of Zhejiang Province(LY17F020025).
文摘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.
基金Supported by the National Natural Science Foundation of China(No.31702375)the Fundamental Research Funds of Zhejiang Sci-Tech University(No.2019Q047)。
文摘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.
文摘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 proliferation
文摘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.
基金funded by the National Natural Science Foundations of China(41522105 and 41571130052)Guangdong Natural Science Funds for Distinguished Young Scholar(2014A030306041)Special Support Program(2016)
文摘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.
文摘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.
文摘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.
文摘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.
文摘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.
文摘目的:回顾性分析香菊胶囊联合鼓室注射地塞米松治疗慢性分泌性中耳炎(Otitis media with effusion,OME)的临床效果。方法:收集我院2023年3月至2024年3月间收治的98例慢性OME患者临床资料,按治疗方法不同分为西药组和联合组(n=49),西药组进行鼓室注射地塞米松磷酸钠注射液0.2mL治疗,联合组加用香菊胶囊。治疗12 w后,比较两组的疗效;采用美国GSI-61听力计测试各频率的骨导阈值;酶联免疫吸附试验检测耳积液白细胞介素-8(Interleukin-8,IL-8)、白细胞介素-6(Interleukin-6,IL-6)、肿瘤坏死因子-α(Tumornecrosisfactor-α,TNF-α)水平;采用ZODIAC901型中耳分析仪分析鼓室图。结果:治疗12w后,联合组总有效率高于西药组(100.00%vs87.76%)(P<0.05);治疗12w后,联合组各频率(1,2,4,8kHz)下的骨导阈值、耳积液IL-8、IL-6、TNF-α水平均低于西药组(P<0.05);治疗12w后,联合组鼓室图各类型分布情况优于西药组(P<0.05)。结论:香菊胶囊联合鼓室注射地塞米松治疗慢性OME疗效确切,能降低骨导阈值,改善耳积液相关因子水平、鼓室图。
