Severe acute respiratory syndrome coronavirus 2 may cause liver injury via Na^(+)/H^(+) exchanger

The liver has many significant functions,such as detoxification,the urea cycle,gluconeogenesis,and protein synthesis.Systemic diseases,hypoxia,infections,drugs,and toxins can easily affect the liver,which is extremely sensitive to injury.Systemic infection of severe acute respiratory syndrome coronavirus 2 can cause liver damage.The primary regulator of intracellular pH in the liver is the Na+/H+exchanger(NHE).Physiologically,NHE protects hepatocytes from apoptosis by making the intracellular pH alkaline.Severe acute respiratory syndrome coronavirus 2 increases local angiotensin II levels by binding to angiotensinconverting enzyme 2.In severe cases of coronavirus disease 2019,high angiotensin II levels may cause NHE overstimulation and lipid accumulation in the liver.NHE overstimulation can lead to hepatocyte death.NHE overstimulation may trigger a cytokine storm by increasing proinflammatory cytokines in the liver.Since the release of proinflammatory cytokines such as interleukin-6 increases with NHE activation,the virus may indirectly cause an increase in fibrinogen and D-dimer levels.NHE overstimulation may cause thrombotic events and systemic damage by increasing fibrinogen levels and cytokine release.Also,NHE overstimulation causes an increase in the urea cycle while inhibiting vitamin D synthesis and gluconeogenesis in the liver.Increasing NHE3 activity leads to Na+loading,which impairs the containment and fluidity of bile acid.NHE overstimulation can change the gut microbiota composition by disrupting the structure and fluidity of bile acid,thus triggering systemic damage.Unlike other tissues,tumor necrosis factor-alpha and angiotensin II decrease NHE3 activity in the intestine.Thus,increased luminal Na+leads to diarrhea and cytokine release.Severe acute respiratory syndrome coronavirus 2-induced local and systemic damage can be improved by preventing virus-induced NHE overstimulation in the liver.

Na_(2)O对锂铝硅微晶玻璃析晶及性能的影响

采用熔融法制备了不同Na_(2)O含量的透明锂铝硅微晶玻璃,通过DSC、XRD、FESEM等测试方法研究了不同Na_(2)O含量对玻璃析晶及性能的影响。结果表明:Na_(2)O的引入能显著降低玻璃的转变温度和析晶温度,抑制LiAlSi_(4)O_(10)晶相的析出。但Na_(2)O的引入促使微晶玻璃中析出Li_(2)Si_(2)O_(5)新相,并且随着Na_(2)O引入量的增加,Li_(2)Si_(2)O_(5)转变为主晶相。由于晶体尺寸均为纳米级,主晶相的转变对透过率影响较小,微晶玻璃的可见光透过率均高于85%。主晶相的转变有效增强了微晶玻璃的机械性能,其弯曲强度由300 MPa提升至331 MPa。Na_(2)O的引入有效增强了Na-K交换,Na_(2)O含量为4%(质量分数)的Li 2O-Al_(2)O_(3)-SiO_(2)微晶玻璃在410℃的KNO_(3)熔盐中交换6 h后,维氏硬度由7.108 GPa提升至7.403 GPa,弯曲强度由331 MPa提升至470 MPa。

Roles of Na^+/Ca^(2+) exchanger 1 in digestive system physiology and pathophysiology

The Na^+/Ca^(2+) exchanger(NCX) protein family is a part of the cation/Ca^(2+) exchanger superfamily and participates in the regulation of cellular Ca^(2+) homeostasis. NCX1, the most important subtype in the NCX family, is expressed widely in various organs and tissues in mammals and plays an especially important role in the physiological and pathological processes of nerves and the cardiovascular system. In the past few years, the function of NCX1 in the digestive system has received increasing attention; NCX1 not only participates in the healing process of gastric ulcer and gastric mucosal injury but also mediates the development of digestive cancer, acute pancreatitis, and intestinal absorption.This review aims to explore the roles of NCX1 in digestive system physiology and pathophysiology in order to guide clinical treatments.

A New and Original Method to Produce Ca(OH)<SUB>2</SUB>Nanoparticles by Using an Anion Exchange Resin

Ca(OH)2 nanoparticles in hydro-alcoholic dispersion (nanolime) were successfully employed in Cultural Heritage conservation, thanks to the ability to overcome the limiting aspects of traditional lime treatments. Nanolime were currently produced by chemical precipitation process, at high temperature, with long times of synthesis, and after several purification steps to remove undesired secondary phases. In this paper, an innovative, simple and original method for nanolime production was described. The method was based on an ion exchange process between an anionic resin and a calcium chloride aqueous solution, operating at room temperature. A pure Ca(OH)2 nanoparticles suspension can be rapidly obtained after separating the resin from suspension, and any purification step was necessary. The exhausted resins can be regenerated and reused for a cyclic nanolime production. Structural and morphological features of the produced nanolime were preliminarily characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Moreover, XRD measurements allowed estimating nanoparticles reactivity by following their carbonatation process in air, in relation to different water/alcohol ratios and medium or high relative humidity conditions. The produced Ca(OH)2 nanoparticles appeared hexagonally plated, with dimension less than 100 nm and, compared with those obtained by typical wet precipitation method, they proved to be more reactive.

The Effects of Na^+/Ca^(2+) exchange (NCX) on the Repolarization of Canine Ventricular Myocyte-Potential Arrhythmogenic Effect of NCX during a Mis-matched Repolarization and Relaxation Xiamen Zhongshan Hospital, Xiamen Medical College, Xiamen University

Objective Background and Objects: Naturally occurring temporal variability of action potentialduration (APD) in isolated myocytes has been noted. Most of the studies have beenfocusing on analyzes of the differences in ionic channels and currents among theepicardial-, mid-myocardial-(M) and endocardial myocytes, and the rate-dependent (adaptation) characteristics of APD. We have found that the change in APD during achange in frequency of stimulation mostly reflects a change in rate of repolarization at distinct membrane potential levels. We assumed that in the myocytes, there is balancing mechanism, which is constantly adjusting the various ionic currents accommodating to the changing conditions. This intrinsic ability of adaptation is important and may offer some of the consequences of the transmural heterogeneity in adaptation of APD. This adaptive behaviors maybe equally important in maintaining the normal electrophysiological properties and in induction of arrhythmia in a case of error in normal adaptation. Though most studies of Na +/Ca 2+ exchange (NCX) has been emphasized on its reverse activaty during pathyological condition. Our hypothesis is that reverse activaty of NCX also plays an important role in adjusting the repolarization of AP during a physiological condition. A mismatch between action potential (AP) repolarization and relaxation of the contraction can be caused by intracellular Ca 2+ transport abnormalities. Ca 2+ influx via reverse activation of NCX can load the sarcoplasmic recticulum (SR), which has arrhythmogenic effect.Methods We studied the single myocytes from the left ventricle of adult mongrel dogs. During the cell separation, collagenase was perfused through LAD by Langandorff system. We use the patch-clamp system to determinded AP in current clamp mode. Myocyte contraction was imaged by a video camera, shortening of unloaded myocytes was detected by a video edge motion detector, using changes in light intensity at the edges of the myocyte. Results From 60 consecutive recorded APs at a constant 1.0 Hz stimulation under steady state conditions we found there is a variance in the repolarization between 10mV and-40mV. We also found the variance in the APD during the rate adaptation range of repolarization. Fluctuation in the transient may contribute to the APD variability. To test thishypothesis we block the transient by intracellular dialysis with 10 mM EGTA(n=19), this caused a significant reduction in the coefficient variability (CV=SD/mean APD%) from 2.3± 0.8 to 1.3± 0.3 P< 0.01. During a rate change of the stimulation from 0.6 Hz to 1.0 Hz. The AP duration increased from 278±8 msec to 320±9 msec, Mean+SD, n=5, 50 APs, P< 0.05. contraction is accompanied by an after-contraction(A-CON). The relaxation of contraction precedes the repolarization of the AP. We assumed that the enhancement of repolarization and the production of after-contraction can be possibly induced by reverse mode of NCX. Reducing [Na +] o by substitution of 40mM Na + with Li + favors NCX activating the reverse mode, which significantly decreased the dome of the AP from 4.8± 0.3 to -10.6± 1.2mV, P< 0.05, and increased the APD from 330±13 to 368±14 msec. P< 0.05.Conclusions Intracellular calcium transient most likely contributes to the beat-to-beat variance of action potential duration in canine ventricular myocyte. And it attributes to the voltage-dependent switch of NCX mode. Calcium concentration is high inmyocytes during the repolarization, and high intracellular Ca 2+ activates NCX in such a manner, that it generates an inward (positive, depolarizing) current. This current works against the repolarization, it is prolonging it, with other words it increases the duration of the action potential. The magnitude of calcium concentration during repolarization is very much dependent on calcium transport in the SR. The calcium transport in the SR is subject to adrenergic actions, and other physiologic and pathologic regulators. Under pathologic conditions

Na^+/Ca^(2+) Exchange-mediated La^(3+) Entry in Human Lymphocytes

We determined whether La3+ enter human peripheral blood lymphocytes via Na+/Ca2+ exchanger (measured with fura-2). We first compared the sensitivity of fura-2 with La3+ and Ca2+, the result indicates that the sensitivity of fura-2 for La3+ is much greater than for Ca2+. La3+ forms a 1:1 La3+-fura-2 complex (apparent dissociation constant = 1.7x10(-12) mol/L, pH 7.05). Ouabain-pretreated cells, suspended in Na+-free medium, showed that La3+ can enter human lymphocytes via the Na-i(+)/Ca2+ (La3+)(o) exchanger and is found to be about 10(-12) mol/L in cells exposed to 0.4 mmol/L La3+. Otherwise, the higher concentration (0.1 mmol/L) blocks the Na-i(+)/Ca2+(La3+)(o) exchange-mediated influx of Ca2+, but the lower concentration (0.01 mmol/L) appears to increase Ca2+ entry.

EFFECTS OF THE HOE 694 ON TRANSIENT INWARD CURRENT AND NA^+- CA^(2+) EXCHANGE IN GUINEA PIG CARDIOMYOCYTES

To determine the effects of HOE 694, a new and potent Na＋- H＋ exchanger blocker, on transient inward current (Iti) and Na＋- Ca2＋ exchange during hypoxia- reoxygenation in guinea pig cardiomyocytes. Methods. Cardiomyocytes were isolated from adult guinea pig ventricle. Experiment was performed in an experimental chamber that allowed the cells to be exposed to a sufficiently low O2 pressure. The cells were subjected to hypoxia and reoxygenation. The ionic currents were studied with patch clamp technique. Results. In the absence of HOE 694, hypoxia- reoxygenation induced Iti in 12 of 15 experiments; but in cardiomyocytes pretreated with HOE 694 (10～ 50μ mol/L), the incidence of Iti observed during reoxygenation was reduced to 5 of 11 experiments and 3 of 10 experiments, P Conclusions. Blockade of the Na＋- H＋ exchange by HOE 694 could reduce Ca2＋ overload upon hypoxia- reoxygenation, and inhibition of Na＋- H＋ exchange may also indirectly decrease Na＋- Ca2＋ exchange activity during hypoxia.

温阳益气活血方对慢性心力衰竭大鼠心肌组织Na^(+)-K^(+)-ATP酶、Ca^(2+)-ATP酶的影响

目的观察温阳益气活血方对慢性心力衰竭大鼠心肌组织Na^(+)-K^(+)-ATP酶、Ca^(2+)-ATP酶的影响,探讨其治疗心力衰竭的作用机制。方法采用皮下多点注射异丙肾上腺素制备慢性心力衰竭大鼠模型,将成模大鼠随机分为模型组、西药组和温阳益气活血方低、中、高剂量组,每组14只,另设空白组15只,给药组分别予相应药物灌胃,空白组和模型组予等量生理盐水,连续6周。超声检测大鼠心功能,ELISA检测血清脑钠肽(BNP)含量,计算心脏质量指数(HMI),HE染色观察心肌组织病理变化,酶活比色法、免疫组化及RT-PCR检测心肌组织Na^(+)-K^(+)-ATP酶、Ca^(2+)-ATP酶活性及表达。结果与空白组比较,模型组大鼠左室射血分数(LVEF)、左室短轴缩短率(LVFS)显著降低(P<0.01);血清BNP含量显著增加,HMI显著升高(P<0.01);心肌组织大量纤维水肿,胞质疏松,组织边缘心肌纤维溶解,伴有少量淋巴细胞浸润;心肌组织Na^(+)-K^(+)-ATP酶、Ca^(2+)-ATP酶活性显著减弱,蛋白及mRNA表达显著降低(P<0.01)。与模型组比较,温阳益气活血方高剂量组大鼠LVEF、LVFS显著升高(P<0.01);血清BNP含量显著减少,HMI显著降低(P<0.05,P<0.01);心肌纤维水肿、胞质疏松、炎症浸润、细胞空泡变性及纤维溶解程度均有改善;心肌组织Na^(+)-K^(+)-ATP酶和Ca^(2+)-ATP酶活性显著增强,蛋白及mRNA表达显著升高(P<0.01)。结论温阳益气活血方能通过调节心肌Na^(+)-K^(+)-ATP酶、Ca^(2+)-ATP酶活性及表达改善心力衰竭大鼠心功能不全,发挥治疗慢性心力衰竭的作用。

A Brief Study on pH, Exchangeable Ca²⁺and Mg²⁺in Farmlands under Tobacco-Rice Rotation in Xuancheng City of South Anhui

pH, exchangeable Ca2+ and Mg2+ of soil can influence the yield and quality of flue-cured tobacco. Xuancheng city is the dominant tobacco-planting region in Anhui province since 2008. A general soil survey was conducted in Xuancheng city to understand the current situations of pH, exchangeable Ca2+ and Mg2+ of farmlands under tobacco-rice rotation and to decide whether continuous applying dolomite powders to abate soil acidification. In total 124 topsoil samples (0-20 cm) were collected from the typical farmlands and soil pH, exchangeable Ca2+ and Mg2+ were measured. The results showed that soil pH and Ca2+ and Mg2+ in Xuancheng city were generally in the suitable grades, pH ranged from 4.56 to 8.42 with an average of 5.87, exchangeable Ca2+ ranged from 1.01 cmol(1/2Ca2+) kg-1 to 100.55 cmol(1/2Ca2+) kg-1 with an average of 11.07 cmol(1/2Ca2+) kg-1, and exchangeable Mg2+ ranged from 0.14 cmol(1/2Mg2+) kg-1 to 2.86 cmol(1/2Mg2+) kg-1 with an average of 0.81 cmol(1/2Mg2+) kg-1, all spanned from the low grades to the high grades. To the whole Xuancheng city, 37.10%, 62.10% and 72.58% of the surveyed farmlands were in the low grades of pH, exchangeable Ca2+ and Mg2+, respectively, while 52.42%, 25.00% and 20.97% of the farmlands were in the suitable grades, respectively. pH had an extremely significantly positive Napierian logarithm correlation with exchangeable Ca2+ and an extremely significantly positive power correlation with exchangeable Mg2+. In total about 338.2 kg·hm-2 of Ca2+ and 202.4 kg·hm-2 of Mg2+ are annually input into the farmlands, while about 110.4 kg·hm-2 of Ca2+ and 7.4 kg·hm-2 of Mg2+ are annually moved out from the farmlands, exchangeable Ca2+ and Mg2+ were annually increased by 225.2 kg·hm-2 and 187.6 kg·hm-2 in the farmlands, respectively. It is necessary to monitor the farmlands dynamically in order to decide whether continuous applying dolomite powders which should be dependent upon the specific conditions of individual farmlands.

Changes in soluble interleukin-2 receptor level in serum and Na^+ -K^+ -exchanging ATPase activity in semen of infertile men caused by antisperm antibody

Aim: To explore the possible mechanisms of male infertility caused by antisperm antibody (AsAb). Methods: Thesoluble interleukin-2 receptor (sIL-2R) level in serum was analyzed by ELISA and Na^+ -K^+ -exchanging ATPase activi-ty in semen by phosphorus (Pi) assay. Results: The slL-2R level in serum was significantly higher and the Na^+ -K^+ -exchanging ATPase activity in semen significantly lower in AsAb positive infertile men when compared with thecontrols. Conclusion: The AsAb titer varies with the slL-2R level in serum. A decrease in Na^+ -K^+ -exchangingATPase activity in semen may play a role in male infertility caused by AsAb.

Kinetic Process and Conductivity of Ag^+ Ion Exchange for Polycrystalline Na-β"-Al_2O_3

This paper reports the kinetic process of Ag ion exchange for the polycrystalline Na-β'-Al2O3.The interdiffusion coefficients in the process of Ag+ and Na+ ion exchange have been calculated with an 'one dimensional double side diffusion model'. Microstructures of the samples were observed and analysed by XRD, EMPA, SEM. The results of the conductivity measurements for samples with Na+, Ag+ and Na+-Ag+ mobile ions are presented and explained

玉米种子萌发过程中Na^＋、K^＋和Ca^2＋含量变化与耐盐性的关系

玉米耐盐品种登海9号和盐敏感品种浚单18在含0、50、100、150和200mmolL-1 NaCl的营养液中萌发生长,采用等离子质谱分别测定其萌动种子种皮、胚、胚乳和幼苗根、根颈、叶中Na+、K+、Ca2+的含量。结果表明,随着培养液中NaCl浓度的增加,玉米体内Na+含量逐渐升高,在幼苗中表现地下部(根和根颈)显著高于地上部(叶);在萌动种子中,胚中Na+积累量显著高于种皮和胚乳。根系积累Na+能力较强,胚拒Na+能力较弱,种皮具有一定的Na+累积能力。随NaCl浓度的增加,K+和Ca2+含量逐渐降低,尤其是Ca2+含量急剧减少,达38.4%～55.9%(登海9号)和65.6%～78.2%(浚单18)。玉米根、根颈、种皮的Na+积累能力、叶的拒Na+能力和幼苗选择吸收Ca2+的能力可能与品种耐盐性有关。

前胡香豆素对肾型高血压大鼠左室肥厚及心肌胞内钙、Na^+,K^+-ATP酶和Ca^(2+),Mg^(2+)-ATP酶活性的影响

目的 研究前胡香豆素组分对肾型高血压左室肥厚的预防和逆转作用及机制。方法 用两肾一夹肾型高血压左室肥厚大鼠 (RHR)模型 ,测定前胡香豆素组分对其血压、左室湿重、心肌细胞面积、胞内静息钙及胞膜和线粒体ATP酶活性的影响。结果 前胡香豆素组分 ( 3 0mg·kg- 1 ·d- 1 ,ig)预防组及逆转组大鼠血压、左室湿重 体重均较肥厚组明显降低 ;左室心肌细胞面积、胞内静息钙均较肥厚组降低 ;对KCl致钙浓度升高亦明显低于肥厚组 ;两组均可增加心肌细胞膜及线粒体Na+ ,K+ ATP酶和Ca2 + ,Mg2 + ATP酶活性。结论 前胡香豆素组分可预防及逆转RHR左室肥厚 ,减少心肌细胞内钙含量 。

离子色谱法同时测定烟叶中的K^+、Na^+、Ca^(2+)、Mg^(2+)和NH_4^+

以5%盐酸为提取剂,超声提取30min,Dionex CS12A阳离子交换柱作分离柱、IonPacCG12A为保护柱,20.0mmol/L甲磺酸溶液为流动相,流速0.25mL/min,采用离子色谱法同时测定了烟叶样品中的K+、Na+、Ca2+、Mg2+和NH4+。结果表明,该法的RSD<6.22%,回收率为90.9%~109.9%,适合批量烟样中这5种离子的快速分析。

有氧运动对大鼠骨骼肌线粒体Na^+,K^+-ATP酶和Ca^(2+)-ATP酶及线粒体肿胀的影响

背景:研究表明有氧运动可提高线粒体功能,但在不同时期的作用特点还不明确。目的:观察不同周期有氧运动对大鼠骨骼肌线粒体Na+,K+-ATP酶和Ca2+-ATP酶以及线粒体肿胀的影响。方法:将SD大鼠随机分为正常对照组,有氧运动2,4和6周组。正常对照组不进行有氧运动,其余3组则参照BedfordTG标准,采用跑台运动方式,建立有氧运动模型进行相应的运动周期锻炼。测定各组大鼠骨骼肌线粒体Na+,K+-ATP酶和Ca2+-ATP酶的活性以及线粒体肿胀程度。结果与结论:有氧运动2周组各指标与对照组比较无差异。有氧运动4和6周组线粒体Na+,K+-ATP酶、Ca2+-ATP酶活性均增高(P<0.05),线粒体肿胀程度降低(P<0.05)。实验结果表明,有氧运动可保护线粒体Na+,K+-ATP酶、Ca2+-ATP酶的活性,提高线粒体功能,但需要一定的时间积累。

补心方对慢性心衰大鼠心肌Na^+-K^+ATP酶、Ca^(2+)-Mg^(2+)ATP酶及琥珀酸脱氢酶的作用研究

目的研究补心方对心梗后早期大鼠Na+-K+ATP酶、Ca2+-Mg2+ATP酶和琥珀酸脱氢酶(Succinate Dehydrogen-ase,SDH)的影响。方法清洁级大鼠60只,采取结扎冠状动脉左前降支中上1/3部,造成AMI模型,手术成功存活动物随机分为心阳高、中、低剂量组及曲美他嗪组、模型组、假手术组共6组,均予灌胃给药或蒸馏水8周。8周后采用分光光度计检测心梗后早期大鼠心肌Na+-K+ATP酶、Ca2+-Mg2+ATP酶以及SDH水平。结果对心肌细胞ATP酶的影响:模型组大鼠ATP酶含量及SDH活性较假手术组降低(P<0.01)。补心方干预后,心阳高剂量、中剂量、低剂量组Na+-K+ATP酶、Ca2+-Mg2+ATP酶和SDH活性较模型组均升高(P<0.01),但低于假手术组及曲美他嗪组,且随剂量增加,Na+-K+ATP酶、Ca2+-Mg2+ATP酶含量和SDH活性逐渐增强。结论补心方可增强与Na+-K+ATP酶、Ca2+-Mg2+ATP酶含量,提高SDH活力,改善线粒体功能,从而保护心肌,改善慢性心衰大鼠症状,延缓慢性心衰的发生发展。

四神丸对慢性复发型结肠炎大鼠结肠组织LDH、SDH、Na+-K+-ATPase和Ca2+-Mg2+-ATPase活力的影响

目的:探究四神丸对慢性复发型结肠炎大鼠结肠组织乳酸脱氢酶(LDH)、琥珀酸脱氢酶(SDH)、Na+-K+-ATPase和Ca2+-Mg2+-ATPase活力的影响。方法:参考文献复制慢性复发型SD大鼠结肠炎模型,将60只大鼠按随机数字表法分为正常组、模型组、四神丸高、中、低剂量组和美沙拉嗪对照组,观察大鼠一般情况并进行结肠肉眼下及镜下损伤评分,分别采用考马斯亮蓝法检测结肠黏膜总蛋白量、定磷法及分光光度法检测LDH、SDH、Na+-K+-ATPase和Ca2+-Mg2+-ATPase活力变化。结果:与模型组比较,四神丸各组大鼠结肠质量明显减轻,结肠长度增长,以及结肠肉眼下及镜下损伤评分均明显降低,同时SDH、Na+-K+-ATPase和Ca2+-Mg2+-ATPase活力均显著提升,但LDH活力出现明显降低。结论:四神丸可能通过恢复结肠黏膜局部能量代谢水平而达到减轻慢性复发型UC大鼠的目的。

复方红景天对肝纤维化大鼠肝组织Na^+/Ca^(2+)泵、TGF-β1 mRNA表达的影响

目的:探索复方红景天抗实验性大鼠肝纤维化的疗效与可能的分子机制.方法:用CC l4皮下注射法诱导SD大鼠肝纤维化模型,同时给予复方红景天颗粒口服进行干预性治疗,观察大鼠血清Ⅲ型前胶原、Ⅳ型胶原、透明质酸含量及肝组织Na+/Ca2+泵、TGF-β1,Ⅰ型前胶原α1 mRNA表达水平、肝组织病理学变化.结果:与模型组相比,复方红景天可明显降低大鼠血清PCⅢ(μg/L)(164.25±45.68vs265.54±98.21),CⅣ(96.73±14.68vs159.67±29.64),HA(289.35±75.68vs455.79±113.55)水平,(q=4.26,4.94,3.68,均为P<0.05);复方红景天可抑制NCX,TGF-β1,α1(Ⅰ)mRNA表达(半定量积分分别为1.50±0.19vs2.45±0.31,1.06±0.12vs2.47±0.37,1.26±0.17vs2.50±0.40,q值分别为3.52,3.93,4.04,均为P<0.05).肝组织纤维沉积明显减少(肝纤维化积分为2.43±0.70vs3.53±0.68,q=3.69,P<0.05).NCX,TGF-β1 mRNA表达与PCⅢ,CⅣ,HA,α1(Ⅰ)mRNA及肝组织的纤维化积分呈正相关,相关系数r分别为0.52,0.49,0.56,0.48,0.60及0.47,0.61,0.56,0.49,0.51(均为P<0.05).结论:复方红景天良好的抗肝纤维化作用,其分子机制可能与抑制NCX及TGF-β1mRNA表达从而减少胶原纤维合成有关.

新型红色荧光粉Na_2Ca_4(PO_4)_2SiO_4∶Eu^(3+),Bi^(3+)的制备及发光特性

用高温固相法合成了用于白光LED的Na2Ca4(1-x-y)(PO4)2SiO4∶xEu3+,yBi3+红色荧光粉。研究了助熔剂H3BO3、二次煅烧时间和稀土掺杂量等制备条件对样品发光性质的影响。结果表明,在1 200℃、助熔剂H3BO3加入量为样品质量的3.8%时可得到更有利于发光的α-NCPS基质,而且掺入Eu3+、Bi3+之后,基质的晶格结构没有发生明显变化;适宜的二次煅烧时间为1.5 h。Bi3+的共掺杂可以通过能量传递大幅提高Eu3+的发光强度,当Eu3+、Bi3+的摩尔分数分别为x=0.04和y=0.01时,粉体具有最强的红光发射。表明这种荧光粉是一种可很好用于近紫外芯片的白光LED的红色荧光粉。

中药补肾方对心力衰竭大鼠Na^+-K^+ATP酶、Ca^(2+)-Mg^(2+)ATP酶和琥珀酸脱氢酶的作用研究

目的研究补肾方对心力衰竭大鼠Na+-K+ATP酶、Ca2+-Mg2+ATP酶和琥珀酸脱氢酶(SDH)的作用。方法 60只大鼠随机分为模型组、假手术组、曲美他嗪组、补肾低、中、高剂量组,每组10只。采用结扎冠状动脉前降支法制备心力衰竭大鼠模型,术后2周开始灌胃,分别给予药物干预8周。8周后通过颈动脉插管记录大鼠血流动力学改变,包括左室收缩压(LVSP)、左室舒张压(LVEDP)、左室内压上升下降最大速率(±LVdp/dtmax);采用分光光度计检测心力衰竭大鼠心肌Na+-K+ATP酶、Ca2+-Mg2+ATP酶以及SDH水平。结果模型组大鼠心肌LVSP和+LVdp/dtmax较假手术组明显降低(P<0.01),而LVEDP和-LVdp/dtmax明显升高(P<0.05);补肾方干预后,中、高剂量大鼠心肌收缩、舒张功能明显优于模型组(P<0.01),以高剂量补肾方改善心力衰竭大鼠心功能明显。补肾方干预后,Na+-K+ATP酶、Ca2+-Mg2+ATP酶和SDH活力高于模型组,但低于假手术组,且随补肾方剂量增加,Na+-K+ATP酶、Ca2+-Mg2+ATP酶和SDH活力逐渐增强。结论补肾方可改善心力衰竭大鼠的心功能,可能与Na+-K+ATP酶、Ca2+-Mg2+ATP酶以及SDH活力增强相关。