改构型酸性成纤维细胞生长因子对顺铂肾损害保护作用的实验研究

目的 研究改构型酸性成纤维细胞生长因子(MaFGF)对顺铂(DDP)引起的体外培养的肾小管上皮细胞损害的保护作用。方法 将原代培养的肾小管上皮细胞接种于96孔培养板：(1)培养72h后加入一系列浓度的DDP,实验组在DDP作用12h后加入不同浓度MaFGF,再培养36h后用WST-8法检测细胞存活率。（2）以DDP建立损伤模型,并在加药后12小时加入一定量的MaFGF,观察MaFGF对肾小管上皮细胞的保护作用。结果 (1) MaFGF能使DDP对肾小管上皮细胞的半数抑制浓度（IC50）升高。（2）DDP组与对照组比较,各生化和酶学指标差异均有统计学意义;而MaFGF + DDP组与对照组比较,SOD、GSH-Px酶活性差异无统计学意义,MDA、NO升高差异仍有统计学意义。结论 MaFGF对DDP损伤的肾小管上皮细胞有明显的保护作用。     

黄精多糖对力竭训练小鼠肝组织损伤的保护作用

通过观察小鼠力竭训练后血ALT、AST,肝组织抗氧化指标、一氧化氮系统及ATP酶生化指标,探讨黄精多糖对小鼠运动性肝组织损伤的保护作用。研究以昆明雄性小鼠30只为研究对象,适应游泳训练后,随机分为3组(每组10只):安静组、运动组、对照组,除安静组外,运动组、运动给药组进行20 d,隔天一次的一次性力竭游泳训练,运动给药组小鼠灌服150 g/kg·d黄精多糖,其他两组小鼠灌服同体积的生理盐水。测定小鼠血清ALT、AST,肝组织MDA、GSH-PX、SOD、CAT、NO、总NOS、iNOS、eNOS、Na~+/K~+-ATP、Ca~(2+)/Mg~(2+)-ATP。测定结果显示:运动组与安静组比较,ALT、AST、MDA、NO、总NOS、iNOS升高,GSH-PX、SOD、CAT、Na~+/K~+-ATP、Ca~(2+)/Mg~(2+)-ATP降低;运动给药组与运动组相比,ALT、AST、MDA、NO、总NOS、iNOS降低,GSH-PX、SOD、CAT、Na~+/K~+-ATP、Ca~(2+)/Mg~(2+)-ATP升高。研究提示:黄精多糖能抑制过度训练引起的肝组织自由基增多,提高抗氧化酶的活性,通过调节i NOS、e NOS的活性,平衡NO的生成量,提高Na~+/K~+-ATP、Ca~(2+)/Mg~(2+)-ATP活性,保持较高的能量供给,维持细胞内外Na~+、K~+、Ca~(2+)、Mg~(2+)的正常分布与运转,对运动性肝组织伤有一定的保护作用。     

甘草黄酮对长期大强度运动小鼠心肌损伤的保护作用

为了探讨甘草黄酮对长期大强度运动小鼠心肌损伤的保护作用机制。本研究选用50只昆明雄性小鼠为研究对象,以每组10只分组,分为安静对照组(A组)、运动训练组(B组)、运动低剂量给药组(C组)、运动中剂量给药组(D组)、以及运动高剂量给药组(E组)。运动低剂量给药组(C组)、运动中剂量给药组(D组)、运动高剂量给药组(E组)训练前分别灌服剂量为5 g/kg/d、10 g/kg/d、15 g/kg/d黄酮溶液;除安静对照组外,运动组小鼠进行为期6周的大强度游泳训练。测定小鼠各组小鼠血清CK-MB、c Tn I,心肌组织中GSH-PX、SOD、CAT、MDA、NOS、NO、Na+/K+-ATP、Ca2+/Mg2+-ATP。结果表明:与安静对照组比较,运动训练组CK-MB、c Tn I、MDA、NO、NOS升高,GSH-PX、SOD、CAT、Na+/K+-ATP、Ca2+/Mg2+-ATP降低。与运动训练组比较,运动低剂量给药组、运动中剂量给药组、运动高剂量给药组CK-MB、c Tn I、MDA、NO、NOS降低,GSH-PX、SOD、CAT、Na+/K+-ATP、Ca2+/Mg2+-ATP升高;与运动低剂量给药组比较,运动高剂量给药组CK-MB、c Tn I、GSH-Px、SOD、Na+/K+-ATP、Ca2+/Mg2+-ATP升高,MDA降低。本研究提示,长期大强度运动导致机体心肌损伤,甘草黄酮可提高机体心肌组织中抗氧酶、ATPase酶的活性,抑制自由基生成、NOS活性,减少NO的生成,维持细胞膜内外Na+、K+、Ca2+、Mg2+的分布平衡,对大强度运动造成的心肌损伤具有保护作用,效果以高剂量黄酮最佳。     

顺铂诱导肾损伤过程中肾皮质脂质过氧化的变化

目的:探讨顺铂肾损伤过程中肾皮质脂质过氧化与肾小管结构改变的关系.方法:雌性Wistar大鼠随机分为生理盐水组、顺铂Ⅰ组、顺铂Ⅱ组、顺铂Ⅲ组,均为尾静脉注射给药,每天一次,连续五天.第六天取血测肌酐(Scr)、尿素氮(BUN)含量,取肾皮质测丙二醛(MDA)含量、超氧化物歧化酶(SOD)活性、谷胱甘肽过氧化物酶(GSH-Px)活性,同时进行肾小管上皮细胞碱性磷酸酶组织化学染色和组织病理学观察.结果:顺铂组Scr、BUN明显升高,肾皮质MDA含量升高,SOD与GSH-Px活性降低,与对照组相比均有显著差异(P＜0.05),且肾皮质SOD活性、GSH-Px活性与Scr、BUN含量呈明显负相关(P＜0.05),肾皮质MDA含量与Scr、BUN含量呈明显正相关(P＜0.05).酶组化显示肾小管上皮细胞碱性磷酸酶大量丢失,病理切片结果显示肾皮质部分肾小管上皮细胞变性、坏死.结论:顺铂引起肾皮质组织的破坏与肾皮质脂质过氧化增强有关,且随剂量增加肾皮质损伤加重.     

迷迭香对运动大鼠肝脏组织脂质过氧化损伤保护作用的研究

本实验选用SD(Sprague Dawley)大鼠,建立大强度耐力训练模型,研究迷迭香对运动大鼠肝脏组织脂质过氧化损伤保护作用。结果显示,1)迷迭香可降低血清丙氨酸氨基转移酶活性,升高肝组织丙氨酸氨基转移酶的活性,都有显著性差异(P<0.05);2)迷迭香可以不同程度地增强肝脏组织中抗氧化酶SOD(superoxide dis-mutase)、CAT(catalase)和GSH-Px(glutathione peroxidase)的活性,其中SOD和CAT的活性增加在安静和运动状态下都有显著性差异(P<0.05),GSH-Px的活性增加在运动状态下具有显著性差异(P<0.05);3)迷迭香可以降低肝脏组织中MDA(malondialdehyde)的含量,无显著性差异(P>0.05)。结论:迷迭香可以增加肝脏组织中的抗氧化酶活性,减轻大强度耐力训练对大鼠肝脏组织造成的脂质过氧化损伤。并且在同一状态下对不同的抗氧化酶活性影响不同。     

高压氧预处理对兔脊髓缺血再灌注损伤的保护机制探讨

目的:探讨高压氧预处理对免脊髓缺血再灌注损伤的保护机制.方法:20只雄性新西兰大白兔,随机分为2组(每组n=10):对照组为常压空气组;HBO组为高压氧预处理组.采用肾下腹主动脉阻断法造成脊髓缺血再灌注损伤,观察两组再灌注后4h、12h、24h、48h时的神经功能评分;再灌注48 h时取出腰段脊髓组织(L5-7)测定脊髓抗氧化酶活性(SOD、CAT及GSH-px)及MAD含量.结果:再灌注4h、12h、24h、48h时,HBO组神经功能学评分均明显优于对照组(P<0.05).再灌注48h时,HBO组脊髓匀浆SOD、CAT及GSH-px活性明显高于对照组(P<0.05),脊髓匀浆MDA含量明显低于对照组(P<0.05).相关性分析发现,再灌注48 h时后肢运动神经功能学评分与脊髓SOD、CAT及GSH-px活性呈正相关(r=0.82,0.65,0.54,P<0.05),与脊髓MDA含量呈负相关(r=-0.69,P<0.05).结论:高压氧预处理对脊髓缺血再灌注损伤的保护机制可能与上调内源性抗氧化酶活性和清除自由基有关.     

红葡萄酒对大鼠肝脏抗氧化酶和脂质过氧化的影响

选用雄性SD大鼠,分别灌胃红葡萄酒、酒精及水。实验90 d中每隔30 d处死一批动物,测定大鼠肝脏匀浆组织中的超氧化物歧化酶(Superoxide dismutase SOD)、过氧化氢酶(Catalase CAT)、谷胱甘肽过氧化物酶(Glutathione peroxidase GSH-Px)活性和脂质过氧化产物丙二醛(Malondialdehyde MDA)含量变化。观察摄入红葡萄酒后大鼠肝脏抗氧化酶活性变化及对肝脏脂质过氧化的影响。结果表明,红葡萄酒能提高SOD活性,且SOD活性与灌胃时间、剂量有一定关系;长期红葡萄酒和酒精摄入可诱导CAT活性增强,加剧肝脏的脂质过氧化(LPO)作用;红葡萄酒组、酒精组0.63、1.25 g/kg剂量GSH-Px活性均明显升高(P<0.05),酒精组1.88 g/kg剂量有极显著性差异(P<0.01);试验初期,红葡萄酒大剂量显著降低肝脏中MDA的含量。试验中期,红葡萄酒中大剂量显著降低MDA含量。试验末期,红葡萄酒大剂量和酒精中大剂量显著升高肝脏中MDA含量。     

针刺联合依达拉奉对缺血再灌注大鼠视网膜自由基代谢的影响

目的:研究针刺联合依达拉奉对大鼠视网膜缺血再灌注时自由基代谢的影响.方法:大鼠随机分为五组:假手术组、模型组、针刺组、依达拉奉组和联合(针刺+依达拉奉)组.建立缺血再灌注模型,于造模后1d,行视网膜电流图(ERG)检查,取视网膜组织,测定各组MDA含量及T-SOD、GSH-Px、CAT活性的变化.结果:①ERG a、b波振幅相对恢复率:联合组、针刺组及依达拉奉组与模型组相比,a、b波振幅相对恢复率升高,差异有显著性(P＜0.05),与针刺组和依达拉奉组相比,联合组作用更为显著(P＜0.05).②MDA含量及T-SOD、GSH-Px、CAT活性:联合组、针刺组及依达拉奉组与模型组相比,MDA显著降低,SOD、GSH-Px、CAT显著升高,差异有显著性(P＜0.05),联合组作用显著优于针剌组或依达拉奉组(P＜0.05).结论:针刺联合依达拉奉具有干预自由基代谢作用,明显减轻缺血再灌注引起的视网膜氧化应激损伤,对视网膜功能起保护作用.     

大鼠肢体缺血/再灌注后的心肌损伤和NO的保护效应

目的:探讨大鼠肢体缺血/再灌注(LI/R)后心肌的损伤性变化及NO的保护效应。方法:制备LI/R动物模型,将Wistar大鼠随机分为4组(n=10):C(control)组、I/R组、L-Arg组和L-NAME组。用生物化学方法测定大鼠血浆CK、CK-MB及NO水平,测定心肌组织XOD、SOD、MDA含量。用BL-420生物机能实验系统监测大鼠MAP、LVSP、±dp/dtmax等。结果:LI/R后,血浆CK、CK-MB水平均明显升高(P<0.01);心肌组织SOD活性降低而MDA、XOD含量增加(P<0.01或P<0.05);MAP、LVSP、dp/dtmax、-dp/dtmax均降低(P<0.01或P<0.05);血浆NO水平在L-Arg组明显升高(P<0.01),在L-NAME组显著降低(P<0.05)。结论:大鼠LI/R可引起心肌损伤,机体的氧化应激状态可能是其发生机制之一;提高体内NO水平可在一定程度上减轻LI/R后心肌损伤的程度。     

辐射所致小鼠肾脏氧化损伤及川芎嗪的保护作用

目的:研究川芎嗪对辐射所致小鼠肾脏氧化损伤的预防和治疗作用。方法:采用60Co-γ射线5 Gy全身单次照射小鼠造模,在照射前和照射后分别于每天腹腔注射川芎嗪130 mg/kg,连续给药10 d,进行预防和治疗,并设对照组,观察肾组织中丙二醛(MDA)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、还原型谷胱甘肽(GSH)、谷胱甘肽过氧化物酶(GSH-Px)及总抗氧化力(T-AOC)的变化。结果:与阴性对照组比较,照射可显著增加肾组织中MDA的含量(P<0.05),降低SOD、CAT的活性(P<0.05),升高GSH-Px活性(P<0.05),降低GSH含量(P<0.05),使肾组织T-AOC下降(P<0.05),。与照射组比较,给予川芎嗪预防和治疗后,均可降低肾组织MDA含量(P<0.05),升高肾组织T-AOC(P<0.05),且治疗组优于预防组,与阴性对照组无显著性差异。同时,预防组可使SOD活性和GSH含量升高(P<0.05),治疗组可使SOD和CAT活性增高(P<0.05),但均对GSH-Px活性无显著影响(P>0.05)。结论:川芎嗪具有很好的抗氧化作用,无论预防和治疗均可降低辐射所致小鼠肾脏的氧化应激损伤,并且治疗效果优于预防效果。     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

Comparative morphology of the carpel in the Liliaceae: Hewardieae, Petrosavieae, and Tricyrteae

The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.     

Enterovirus 71 3C proteolytically processes the histone H3 N-terminal tail during infection

Highlights
1. The N-terminal tail of histone H3 is specifically cleaved during EV71 infection.
2. Viral protease 3C is identified as a protease responsible for proteolytically processing the N-terminal H3 tail.
3. Our finding reveals a new epigenetic regulatory mechanism for Enterovirus 71 in virus-host interactions.     

Detection of EBV and HHV6 in the Brain Tissue of Patients with Rasmussen’s Encephalitis

Rasmussen’s encephalitis (RE) is a rare pediatric neurological disorder, and the exact etiology is not clear. Viral infection may be involved in the pathogenesis of RE, but conflicting results have reported. In this study, we evaluated the expression of both Epstein-Barr virus (EBV) and human herpes virus (HHV) 6 antigens in brain sections from 30 patients with RE and 16 control individuals by immunohistochemistry. In the RE group, EBV and HHV6 antigens were detected in 56.7% (17/30) and 50% (15/30) of individuals, respectively. In contrast, no detectable EBV and HHV6 antigen expression was found in brain tissues of the control group. The co-expression of EBV and HHV6 was detected in 20.0% (6/30) of individuals. In particular, a 4-year-old boy had a typical clinical course, including a medical history of viral encephalitis, intractable epilepsy, and hemispheric atrophy. The co-expression of EBV and HHV6 was detected in neurons and astrocytes in the brain tissue, accompanied by a high frequency of CD8⁺ T cells. Our results suggest that EBV and HHV6 infection and the activation of CD8⁺ T cells are involved in the pathogenesis of RE.     

Perinatal Vertical Transmission of Chikungunya Virus in Ruili,a Town on the Border between China and Myanmar

正Dear Editor,Chikungunya virus (CHIKV), an arbovirus in the family of Togaviridae, genus Alphavirus, is transmitted by the A.aegyptii or A. albopictus mosquito, and causes disease in humans characterized by fever, rash, and arthralgia (Silva and Dermody 2017; Suhrbier 2019). It was first reported in 1953 in Tanzania, and caused only a few outbreaks and sporadic cases in Africa and Asia in last century. However, in the epidemic in 2004, CHIKV acquired mutations that conferred enhanced transmission by the A. albopictus mosquito(Schuffenecker et al. 2006). Since then, it has successively caused outbreaks in Africa, the Indian Ocean, South East Asia, the South America, and Europe (Zeller et al. 2016).     

Development of a Novel Reverse Transcription Loop-Mediated Isothermal Amplification Method for Rapid Detection of SARS-CoV-2

In conclusion, the novel visual RT-LAMP assay is a simple, rapid, and sensitive approach for detection of SARS-CoV-2, and it is ready for application in primary care and community hospitals or health care centers, and even patients' own houses in response to the current SARS-CoV-2 epidemic because the assay does not require sophisticated equipment and skilled personnel. Furthermore, it is also ready to be used in fields for screening samples from wild animals and environments to facilitate the identification of potential intermediate hosts that mediate the cross-species transmission of SARS-CoV-2 from bats to humans.