麝香、麝香酮对体外培养大鼠视网膜神经细胞存活影响的比较研究

为比较麝香、麝香酮对大鼠视网膜神经细胞存活的影响,分别单独将麝香、麝香酮加入大鼠视网膜神经细胞混悬液中,用MTT法评价麝香、麝香酮对大鼠视网膜神经细胞存活的影响;另分别在麝香和麝香酮中加入定量的m-NGF,采用同法评价麝香(或麝香酮) m-NGF对大鼠视网膜神经细胞存活的影响。结果表明,单独应用麝香、麝香酮对体外培养大鼠视网膜神经细胞的存活无明显影响(P>0.05);在加入定量m-NGF的条件下,麝香、麝香酮分别在50～800μg/mL和100～800μg/mL的浓度范围明显促进大鼠视网膜神经细胞的存活,且呈一定的量效关系。说明麝香、麝香酮无直接促进视网膜神经细胞存活的作用;麝香、麝香酮均与NGF协同增进视网膜神经细胞的存活;麝香酮是麝香中增强NGF生物效应的有效成分之一。     

鳖的形态学统计分析

利用生物统计学的方法对鳖的形态进行了分析 ,结果如下 :鳖的年龄 (Y)与体重 (X)的一元回归方程为 :Y =0 0 0 736 1X 0 4 534,年龄 (Y)与腹甲长 (X)的一元回归方程为 :Y =0 2 4 59X- 0 5480 ;雌雄鳖尾长差异显著 (P <0 0 5) ,雄鳖体重 (Y)对尾长 (X)的一元回归方程为 :Y =2 56 6 4X - 82 8 6 0 ;野生鳖体重 (Y)对背甲长 (X1)、体高 (X5)、头长 (X8)、眼径 (X9)、口裂 (X12 )等 13个形态学指标的最优多元回归方程为 :Y =880 51 6 79 16X1- 10 6 0 91X5 146 4 72X8- 82 96 6 4X9- 3142 0 9X12 ;控温条件下快速生长鳖体重 (Y)对腹甲宽 (X4 )、体高 (X5)、头发 (X8)、眼间距(X10 )、尾长 (X13)等 13个形态学指标的最优多元回归方程为 :Y =- 97 4 6 38 99X4 30 2 6X5-2 9 34X8 140 83X10 - 30 4 2X13.     

番茄田二代棉铃虫发生规律及药剂防治

第 2代棉铃虫Helicoverpaarmigera是危害番茄最严重的世代 ,95 %左右的卵产在番茄植株顶尖至第 4复叶层的嫩梢、嫩叶、果萼和茎基上 ,6月 2 0日至 7月 5日累计平均每株落卵 32 8粒。在番茄上第 2代棉铃虫的卵量和幼虫量与第 1代蛾量密切相关 ,卵量 (Y1)与第 1代蛾量 (x)关系式为 :Y1=-31 5 9+ 1 7783X ,n =6 ,r=0 85 6 2 ,幼虫量 (Y2 )与第 1代蛾量 (X)关系式为Y2 =31 3+ 0 1 34X ,n =6 ,r=0 86 5 2 。在第 2代棉铃虫产卵初盛期应用Bt菌剂含孢子 1 0 0亿个 mL ,2 0 0倍液喷雾 3次 ,或 1 8%阿维菌素 1 2 1 5g (a .i.) hm2 兑水喷雾 2次 ,防效显著。     

气相色谱法检测交联透明质酸中交联剂残留量

目的建立一种二乙烯基砜交联透明质酸中交联剂二乙烯基砜残留量的检测方法。方法采用气相色谱法检测二乙烯基砜残留量,色谱柱为HP-5毛细管色谱柱（Agilent 19091J-413：325℃：30m×320μm×0．25μm）,程序升温,采用FID检测器,载气为氮气。结果二乙烯基砜在1μg／g-50μg／g线性关系良好,线性相关系数r=0．9999,平均回收率为97．8％（RSD为2．6％,n=5）。结论气相检测交联透明质酸中交联剂含量,结果准确,方法简单可靠,可用于交联透明质酸水凝胶产品质量控制。     

胃内容物中甲卡西酮LC-MS/MS检验方法研究

目的:建立胃内容物中甲卡西酮及其代谢物卡西酮的LC-MS/MS检验方法。方法:以双苯戊二氨酯(SKF525A)为内标,Column Eclipse Plus C18色谱柱(1.8μm, 100 mm×3 mm)为固定相,流动相为0.1%甲酸水溶液和乙腈,梯度洗脱,流速为0.3m L/min,进样量为1μL。通过电喷雾离子源(ESI),利用正离子多反应监测模式(MRM)进行检测。结果:胃内容物中甲卡西酮检验方法线性范围为1-5000 ng/g,标准曲线方程Y=0.026X+0.4501(R2=0.9998),检出限为0.5 ng/g,定量限为1.0 ng/g;卡西酮的检验方法线性范围为2-5000 ng/g,标准曲线方程Y=0.0099X+0.1576(R2=0.9997),检出限为1.0 ng/g,定量限为2.0 ng/g。结论:该方法操作简便,检测灵敏度较高,可用于甲卡西酮中毒案件胃内容物中甲卡西酮及其代谢物卡西酮的检验。     

rhIGF-1等电点的测定

目的：通过测定rhIGF-1等电点为例,建立一种快速测定蛋白质等电点的方法。方法：采用等电聚焦电泳（isoelectric focusing,IEF）和高效液相色谱（HPLC）连用的方法,主要以7．5％的凝胶浓度、3％的交联度及6％的两性电解质浓度配置凝胶,电泳后的凝胶经凝胶成像系统和HPLE分析确定目的条带及其pI值。结果：rhIGF-1的等电点为pI=8．20,pH梯度曲线线形回归方程为Y=0．0664X＋3．8217,相关系数r达0．9956,说明等电聚焦电泳测定结果准确。     

藏药椭圆叶花锚中抗肝炎有效成分的含量测定

运用RP-HPLC建立了花锚中青兰苷、去甲氧基花锚苷和花锚苷的含量分析方法,为栽培花锚替代野生花锚入药提供一定的科学依据。花锚苷、去甲氧基花锚苷和青兰苷分别在0．68～3．40μg(r=0．9998)、0．36～1．80μg(r=0．9990)和0．80～4．00μg(r=0．9979)有良好线性关系,平均回收率分别为100．39％(RSD=2．60％)、99．79％(RSD=3．55％)和100．71％(RSD=2．19％)。栽培花锚中花锚苷和去甲氧基花锚苷的含量(抗肝炎活性成分)和在野生花锚中的含量相比无明显差别,可以初步证明栽培花锚可以替代野生花锚入药。     

HPLC法测定甘草酸和甘草苷的含量

目的:建立以HPLC法同时测定甘草中甘草酸和甘草苷含量的方法.方法:采用C18柱(4.6mmx15cm,5μm)为分析柱;以乙腈-1%醋酸溶液为流动相;流速为0.6ml·min-1;柱温25℃;采用外表法定量测定.结果表明甘草酸在4.16-28.0μg/ml范围内,回归方程为Y=10562.8X+30963(r=0.9999);甘草苷在13.0-23.4μg/ml范围内,回归方程为Y=12857.4X+16437(r=0.9997),平均加样回收率均大于96.08%,日内、日间的RSD值分别小于1.41%和1.85%.结论本方法操作简单、准确、快速、重现性好,其它组分干扰少,可用于甘草酸和甘草苷的含量测定.     

麝香、麝香酮对大鼠视网膜神经细胞毒性的对比考察

为考察麝香、麝香酮对体外培养大鼠视网膜神经细胞的最大无毒浓度(TC0),比较两者的细胞毒性,分别将倍比稀释的麝香、麝香酮试液加入大鼠视网膜神经细胞中培养观察,用MTT法测得存活细胞OD值,经公式计算麝香与麝香酮对细胞的最大无毒浓度(TC0)及对50%细胞产生毒性的浓度(TC50)。结果表明,麝香、麝香酮对大鼠视网膜神经细胞的TC0分别为1.29、7 mg/mL;麝香对其的TC50为8.7 mg/mL。说明麝香对体外培养大鼠视网膜神经细胞的毒性高于麝香酮。     

灰色系统及其在动物资源管理中的应用——甘孜州麝香资源动态及其评价

本文将灰色系统理论及其模型运用到野生动物资源管理及保护利用的研究中。四川省甘孜藏族自治州是我国重要的产香区,我们通过收集该区历年麝香产量分析了该区麝香资源动态规律及其与人为活动的关系。我们利用该区1967—1975年麝香收购量建立的麝香资源状态及预测模型是:X~(1)(t)=-108214.5273e~(-0.0973(t-t_0))+1839.9007e~(-1.1494(t-t_0))+113969.1266关联度S=0.9278,1968—1975 年预测产量与实际产量十分接近,其平均误差为-5.6829％(-16.6075～9.3553％)。     

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.