硒酸精氨酸对小鼠酒精性肝损伤的保护作用

目的探讨硒酸精氨酸对小鼠酒精性肝损伤的保护作用。方法用连续灌服酒精的方法建立小鼠酒精性肝损伤模型。将60只雄性小鼠随机分为四组：对照组,模型组,硒酸精氨酸处理组和二氧化硒处理组。连续灌胃8周后,测定小鼠血清中天冬氨酸氨基转移酶（AST）,丙氨酸转移酶（ALT）,肝匀浆中超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GPx）、谷胱甘肽（GSH）的含量。对肝脏切片做HE染色和Masson染色,在光镜下观察肝脏病理学变化。结果硒酸精氨酸能显著降低酒精性肝损伤引起的AST的升高（P〈0．01）,有效保持了肝脏中GPx和SOD的活性（P〈0．01）。病理学观察结果与酶学变化相一致,硒酸精氨酸对肝脏的保护作用明显优于二氧化硒。结论硒酸精氨酸对小鼠酒精性肝损伤具有显著的保护作用,效果也优于二氧化硒。     

小茴香对肝纤维化大鼠脂质过氧化水平的影响

目的：研究小茴香对肝纤维化大鼠的脂质过氧化水平的影响。方法：取Wister大鼠100只,随机取12只设为正常组,其余采用四氯化碳（CCL4）复合因素法复制肝纤维化大鼠模型,复制成功后随机分为模型对照组、小茴香组和复方丹参组（n=12）;相应药物干预8周后,镜检肝组织形态学改变;全自动生化分析仪检测外周血清丙氨酸转氨酶（ALT）、天冬氨酸转氨酶（AST）水平与血清总蛋白（TP）、白蛋白（ALB）含量;生化法检测肝组织羟脯氨酸（HYP）与血清丙二醛（MDA）含量及超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GSH—PX）、过氧化氢酶（CAT）活性。结果：HE结果显示：模型组肝脏炎症与脂肪变性明显,经小茴香干预后明显改善。生化检测结果显示：与正常组比较,模型组ALT、AST水平显著升高（P〈0．05）,TP、ALB含量显著降低（P〈O．05）,HYP、MDA含量显著增加（P〈0．05）,而SOD、GSH—PX和CAT活性显著降低（P〈0．05）;与模型组比较,小茴香组ALT、AST水平显著下降（P〈0．05）,TP、ALB水平显著升高（P〈0．05）;HYP、MDA含量显著降低（P〈0．05）,SOD、GSH—PX和CAT活性显著提高（P〈0．05）。结论：小茴香的抗肝纤维化作用可能与调节大鼠脂质过氧化水平有关。     

黔产毛蒟水提物对急性肝损伤小鼠的保护作用

探讨黔产毛蒟水提物(PTE)对四氯化碳(CCl_4)诱导小鼠急性肝损伤的保护作用及其作用机制。本研究中将50只昆明种小鼠随机分为5组,各组10只,分别为空白组、模型组(0.01 g/kg的0.15%CCl_4菜油溶液造模)、PTE组(低剂量组0.5 g/kg和高剂量组1.0 g/kg)和阳性对照组(联苯双酯0.15 g/kg)。检测各组小鼠谷丙转氨酶(ALT)、谷草转氨酶(AST)、肿瘤坏死因子(TNF-α)含量;测定肝组织匀浆中脂质过氧化产物丙二醛(MDA)含量及超氧化物歧化酶(SOD)活性;计算肝脏的湿重指数;HE染色法观察肝脏组织的病理学变化。与空白对照组相比,模型组血清ALT、血清AST、肝脏指数、肝组织MDA含量以及血清TNF-α明显增高(均P0.01),肝组织SOD活性明显降低(P0.01),肝组织病理损伤明显。与模型组相比,PTE高剂量组和阳性对照组血清ALT显著降低(P0.01),PTE低、高剂量组和阳性对照组血清AST、肝脏指数、肝组织MDA含量以及血清TNF-α含量均明显降低(P0.05或P0.01),肝组织SOD活性明显升高(P0.01),并减轻了肝组织病理损害。PTE可减轻CCl_4诱导的急性肝损伤,其机制可能与抗氧化、抑制TNF-α的产生有关。     

基于HMGB1/TLR4/NF-κB信号通路探讨忍冬苷对脓毒症肝损伤大鼠的影响

摘要 目的：基于高迁移率族蛋白B1（HMGB1）/Toll样受体4（TLR4）/核因子κB（NF-κB）信号通路探讨忍冬苷对脓毒症肝损伤大鼠的影响。方法：60只雄性SD大鼠随机分为模型组、对照组、阳性对照组（地塞米松10 mg/kg）、忍冬苷低剂量（7.5 mg/kg）、忍冬苷中剂量（15 mg/kg）、忍冬苷高剂量（30 mg/kg）组,每组10只。采用盲肠结扎穿刺法建立大鼠脓毒症模型。实验结束后麻醉大鼠取血制备血清,检测血清中超氧化物歧化酶（SOD）活性和丙二醛（MDA）、白介素-6（IL-6）、肿瘤坏死因子-α（TNF-α）、白介素-10（IL-10）含量;分离肝组织称重,计算肝脏指数,一部分用于HE染色观察肝组织病理变化,一部分用于制备组织匀浆检测组织中肝功能指标谷丙转氨酶（ALT）、天冬氨酸转氨酶（AST）活性及HMGB1、TLR4、NF-κB蛋白表达。结果：与对照组比较,模型组大鼠血清中MDA、TNF-α、IL-6含量、肝脏指数以及肝组织中AST、ALT活性、HMGB1、TLR4、NF-κB蛋白表达显著增加（P＜0.05）,SOD活性与IL-10含量显著下降（P＜0.05）;且肝组织出现明显病灶,肝细胞水肿变性,大量炎性细胞浸润。与模型组比较,阳性对照组与忍冬苷各剂量组大鼠血清中MDA、TNF-α、IL-6含量、肝脏指数以及肝组织中AST、ALT活性、HMGB1、TLR4、NF-κB蛋白表达显著降低（P＜0.05）,SOD活性与IL-10含量显著升高（P＜0.05）;忍冬苷低、中剂量组仍可见病灶和水肿,但病变减轻;地塞米松组与忍冬苷高剂量组肝细胞结构趋于正常,未发现病灶。与阳性对照组比较,忍冬苷低、中剂量组大鼠血清中MDA、TNF-α、IL-6含量、肝脏指数以及肝组织中AST、ALT活性、HMGB1、TLR4、NF-κB蛋白表达显著升高（P＜0.05）,SOD活性与IL-10含量显著降低（P＜0.05）;忍冬苷高剂量组上述指标无显著差异（P＞0.05）。结论：忍冬苷通过下调HMGB1/TLR4/NF-κB信号通路的表达,抑制氧化应激,减轻炎症反应,改善肝功能,发挥对脓毒症肝损伤的保护作用。     

粒细胞集落刺激因子对小鼠内毒素性急性肝损伤的保护作用

目的观察粒细胞集落刺激因子对小鼠内毒素性急性肝损伤的作用,并对其机制进行初步探讨。方法昆明（KM）小鼠随机分为模型组、预防组和正常组,模型组小鼠腹腔注射内毒素（LPS）10mg／kg或30mg／kg,预防组于造模前1小时皮下注射重组人粒细胞集落刺激因子（rhG-CSF）500btg／kg,正常组注射等剂量的生理盐水,观察各组小鼠的存活率及造模后6h、24h小鼠肝脏组织病理变化,全自动生化分析仪检测血清丙氨酸氨基转移酶（ALT）和天门冬氨酸氨基转移酶（AsT）的水平,酶联免疫吸附试验（ELISA）检测血清肿瘤坏死因子（TNF—a）和白介素10（IL-10）的水平。结果预防组小鼠存活率与模型组相比无明显差异（80％VS66．7％,P〉0．05）;预防组肝组织损伤及肝功能酶学指标ALT和AST均好于模型组（P〈0．05）;预防组小鼠血清IL-10的表达水平在6小时点明显高于模型组（P〈0．05）,24小时点与模型组相比无明显差异（P〉0．05）,血清TNF-a表达水平与模型组相比差异无统计学意义（P〉0．05）。结论粒细胞集落刺激因子对小鼠内毒素性急性肝损伤具有保护作用,对小鼠的存活率无明显影响。     

银杏叶提取物对对乙酰氨基酚诱导的小鼠急性肝损伤的保护作用

目的：探究银杏叶提取物（GBE）对对乙酰氨基酚（APAP）诱导的小鼠急性肝损伤的保护作用及其机制。方法：30只小鼠随机分为对照组、模型组、GBE低、中、高剂量组（50,100,and 200 mg·kg^-1）,每组6只。除对照组外,剩余小鼠腹腔注射APAP （300 mg/kg）一次,随后GBE低、中、高剂量组按照相应剂量灌胃给药,治疗2 d后取材。观察各组肝脏大体情况和肝组织的病理组织学变化;取血测定各组小鼠血清中ALT、AST的活性和TNF-α、IL-6的水平;取肝检测各组肝组织中SOD、MPO的活性和GSH、MDA的含量;通过Western blot检测各组肝组织中Nrf2、HO-1蛋白的表达量。结果：与对照组相比,模型组肝脏明显肿大,病理表现差,血清中ALT、AST、TNF-α、IL-6的水平显著升高（P<0.01）,肝组织中GSH的含量和SOD的活性显著降低（P<0.01）,MDA的含量和MPO的活性显著升高（P<0.01）,Nrf2、HO-1蛋白表达明显下调（P<0.01）。与模型组相比,GBE组肝脏肿大减轻,病理表现有所改善,血清中ALT、AST、TNF-α、IL-6的水平显著降低（P<0.01）,肝组织中GSH的含量和SOD的活性显著提高（P<0.01）,MDA的含量和MPO的活性显著降低（P<0.01）,Nrf2、HO-1蛋白表达上调（P<0.05）,其中高剂量GBE组治疗效果最明显。结论：GBE可对APAP诱导的小鼠急性肝损伤具有保护作用,其作用机制可能是通过Nrf2/HO-1抗氧化途径发挥作用。     

柴达木盆地唐古特白刺籽油保护肝损伤作用研究

对柴达木盆地唐古特白刺种籽油保护化学性肝损伤作用进行了研究.将小鼠按体重随机分为白刺籽油高、中、低剂量组,另设空白对照组和联苯双酯、藏茵陈阳性对照组.小鼠连续灌胃给药15 d后,用CCl4进行肝损伤,测定小鼠血清谷丙转氨酶（ALT）、谷草转氨酶（AST）;肝脏过氧化脂质（LPO）降解产物丙二醛（MDA）和谷胱甘肽过氧化物酶（GSH-Px）的含量.结果显示,白刺籽油对血清ALT、AST具有显著的抑制作用,显著拮抗肝脏MDA的升高,显著提高肝脏GSH-Px含量.表明白刺籽油具有明显的保护化学性肝损伤的保健作用.     

抑制性寡脱氧核苷酸对实验性肝损伤细胞因子的影响

探讨抑制性寡脱氧核苷酸（suppressive oligonucleotides,Sup ODN）对刀豆蛋白A（Con A））诱导的小鼠实验性肝损伤的保护作用．实验采用Balb／C小鼠40只,随机分4组．分别为生理盐水（NS）组、对照寡脱氧核苷酸（control oligonucleotides,Con ODN）组、环孢菌素A（cyclosporin A,CsA）组、Sup ODN组．Con A（20mg,kg）尾静脉注射Ba1b/C小鼠,2h时腹腔给药,给药8h时观察小鼠的血清丙氨酸氨基转移酶（ALT）活性、死亡率;检测血清TNF-α、IFN-γ、TIL-4水平;RT-PCR检测肝组织TNF-α、IFN-γ mRNA的表达;并观察肝组织的病理改变．发现Sup ODN组与NS组、Con ODN组相比,ALT活性明显降低（P〈0．01）;与NS组、Con ODN组和CsA组比较,IFN-γ明显降低（P〈0．01）,IL-4明显升高（P〈0．01）,TIFN-γ mRNA表达亦显著减少：而且Sup ODN可明显减轻肝脏炎性细胞浸润和肝细胞坏死（P〈0．05）．实验表明Sup ODN对Con A小鼠实验性肝损伤有明显保护作用．     

茶多酚对酒精性肝病大鼠核因子κB及环氧合酶2表达的影响

目的观察茶多酚对大鼠酒精性肝病的干预作用及其对核因子kB（NF-kB）和环氧合酶2（COX-2）表达的影响。方法32只Wistar大鼠,随机分为3组,对照组（6只）用玉米油;模型组（13只）用白酒＋玉米油;茶多酚组（13只）在模型组基础上给予茶多酚。7周后处死大鼠,检测血清中天门冬氨酸转氨酶（AST）、丙氨酸转氨酶（ALT）和丙二醛（MDA）含量。光镜和电镜观察肝组织细胞及亚细胞结构的改变;逆转录聚合酶链反应（RT-PCR）测肝组织中NF-kB及COX-2的mRNA表达;免疫组织化学法检测肝组织中NF-kB和COX-2蛋白的表达。结果模型组肝细胞损伤明显,茶多酚组较轻。模型组大鼠血清ALT较对照组明显升高（P〈0．01）;与模型组相比,茶多酚组大鼠血清ALT、AST、MDA明显降低（P〈0．01）。RT-PCR及免疫组化均显示,肝组织中NF-kB及COX-2表达模型组较对照组明显升高（P〈0．01）,茶多酚组较模型组明显降低（P〈0．01）。结论茶多酚对大鼠酒精性肝损伤有保护作用,可能是通过抑制NF-kB的活化和COX-2的表达来实现的。     

蟛蜞菊内酯对四氯化碳致小鼠肝损伤的保护作用

目的:研究中药活性物质蟛蜞菊内酯的保肝作用及其机制。方法:采用小鼠腹腔注射CCl4制作肝损伤模型,测定小鼠血清中谷丙转氨酶(ALT)、谷草转氨酶(AST)、丙二醛(MDA),谷胱甘肽(GSH)和超氧化物歧化酶(SOD)指标,进行肝脏的组织病理学检查,观察蟛蜞菊内酯对CCl4所致肝损伤的保护作用。结果:蟛蜞菊内酯能明显降低肝损伤小鼠的血清ALT、AST和肝组织匀浆中MDA含量,SOD活力增强,明显减轻肝组织变性。结论蟛蜞菊内酯对CCl4引起的肝损伤有明显的保护作用,其机制可能与其抗氧化作用有关。     

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.