"东湖早"枇杷的组织培养(简报)

以“东湖早”枇杷的幼胚为外植体,在B5 2,4-D 0.5 mg/L 6-BA 1.0 mg/L培养基上诱导愈伤组织,经继代培养基B5 2,4-D 0.1 mg/L 6-BA 0.5 mg/L培养后,置于B5 6-BA 1.5 mg/L培养基上诱导分化,产生不定芽。将幼苗切段转接到MS 6-BA 2.0 mg/L NAA 0.5 mg/L培养基上进行增殖培养,繁殖系数为3~5。待芽长2~3cm时再分切成单株于1/2MS NAA 0.5 mg/L培养基上,可正常生根。     

绿巨人白掌不同外植体组织培养研究

本文研究白鹤芋属观赏品种绿巨人白掌的茎顶、叶片、叶柄和幼花序的组织培养和快速繁殖技术。茎顶培养以0.2mg／LNAA 3．0mg／L6-BA培养效果较好;叶片诱导适宜的培养基为0．5mg／LNAA 5．0mg／L6-BA,分化培养基为0．2mg／LNAA 3．0mg／L6-BA;叶柄以0．5mg／L2,4-D 3．0mg／L6-BA诱导效果最好,分化适宜培养基为0．5mg／LNAA 3．0mg／L6-BA;幼花序胚状体的诱导则以0．5mg／L2,4-D 5．0mg／L6-BA效果最好,成苗培养基为0.5mg／LNAA 3．0mg／L6-BA;255mg／L的KH2P04比较／比较适合于绿巨人白掌丛芽的增殖;生根培养基以1／2MS 0.50mg／LNAA较适宜。     

野生高乌头组织培养及快速繁殖

以野生高乌头的嫩叶和叶柄为材料进行高乌头的组织培养研究。结果表明:高乌头的愈伤诱导培养基为1)MS+2,4-D4.0mg/L,2)MS+2,4-D3.0mg/L+6-BA0.5mg/L;愈伤分化培养基为MS+2,4-D0.2mg/L+6-BA1.0mg/L+NAA0.5mg/L;不定芽增殖培养基为MS+2,4-D0.2mg/L+6-BA0.5mg/L+NAA0.1mg/L,平均增殖倍数为5.5;生根培养基为1/2MS+IBA1.5mg/L,生根数10条以上,生根率95%以上。     

苦马豆的组织培养(简报)

以苦马豆种子在MS无植物生长调节剂的培养基上培养出无菌苗,以子叶和胚轴为外植体,在MS＋6．BA2．0mg／L＋2,4-D0．Smg／L上诱导产生愈伤组织,在MS＋6-BA2．0mg／L＋NAA0．Smg／L培养基上继代培养,继代三次后在MS＋6-BA2．0mg/L培养基上诱导产生丛芽,在MS＋6-BA0．5mg／L培养基上进行幼苗培养,在幼苗长到3～4cm时移至1／2MS＋IBA2．0mg／L培养基上生根。     

留兰香玻璃苗愈伤组织化再生正常植株

植物名称:留兰香(Mentha spicata)。材料类别:玻璃苗梢。培养条件:以MS为基本培养基,诱导愈伤组织添加(1)2,4一D1.0mg/L(单位下同);(2)2,4-D2.0;(3)2,4-D3.0;(4)2,4-D4.0;(5)2,4-D5.0;(6)2,4-D1.0 KT0.1。嫩梢分化培养基为(2),(6)和(7)BA2.0 IBA0.2。生根培养基为(8)1/2MS IBA0.5。培养基含蔗糖3％(生根培     

盾叶薯蓣组织培养技术的优化

以盾叶薯蓣的根状茎、茎段、叶柄、幼叶为材料,进行愈伤组织诱导、分化及再生植株形成的研究。结果表明：盾叶薯蓣不同外植体均能诱导出愈伤组织,其中茎段愈伤组织的诱导率最高;不同激素配比的培养基对愈伤组织的形成有很大的影响：以LS为基本培养基,2,4-D浓度为4．0mg／L、6-BA浓度为1．0mg／L的激素配比诱导率最高,达62．5％;以改良MS为基本培养基,2,4-D浓度为2．0mg／L、6-BA浓度为0．5mg／L的激素配比诱导率最高,达71．4％。筛选到优化的分化培养基为改良MS附加2．0mg／L的6-BA和0．5mg／L的Vc,且能直接诱导出根,并形成完整植株。     

费尔干猪毛菜愈伤组织的诱导、分化及植株再生体系的建立

探讨了植物生长调节剂、外植体等因子对费尔干猪毛菜（Salsola fergartica Drob．）愈伤组织诱导、分化与植株再生的影响。结果表明：2,4-D与6-BA组合使用时,在一定浓度范围内均有愈伤组织产生,最佳的诱导培养基为MS＋2,4-D2．0mg／L＋6-BA0．2mg／L,下胚轴为诱导愈伤组织的最佳材料;愈伤组织继代培养较好的培养基为MS＋NAA0．1mg／L＋6-BA1．0mg／L;愈伤组织不定芽分化培养基为MS＋6-BA0．5mg／L＋NAA0．05mg／L;根分化的培养基为1／2MS＋IBA0．2mg／L,且生根率可达72％。以带柄子叶为外植体,诱导丛生芽的最佳分化培养基为MS＋6-BA1．0mg／L,再生频率可达90．74％。     

小麦遗传转化受体系统建立的研究

选用‘小偃22’和‘宁春16’小麦品种的成熟胚和幼胚进行培养,研究不同种类的胚和培养因子对愈伤组织诱导和分化的影响。结果表明,幼胚和成熟胚的愈伤组织诱导率无明显差异,但较高浓度的2,4-D有利于成熟胚的诱导,而幼胚培养时2,4-D浓度的影响效果因品种而异;两种外植体分化率的高低与KT/IAA的配比均有密切关系,但高浓度的激素水平不利于成熟胚的分化;诱导培养基中低浓度的2,4-D有利于所诱导的愈伤组织的分化。同时,在诱导培养基中添加低浓度的KT能显著提高两品种成熟胚愈伤组织的分化率;各种培养基处理与品种间都存在显著的互作效应,‘小偃22’成熟胚培养的最佳培养基组合为MSD 3.0 mg/L 2,4-D和MSD 0.5 mg/LIAA 1.0 mg/L KT,幼胚培养为MSD 4.0 mg/L 2,4-D和MSD 0.5 mg/L IAA 1.0 mg/L KT;‘宁春16’成熟胚培养为MSD 4.0 mg/L 2,4-D和MSD 1.0 mg/L IAA 1.0 mg/L KT,幼胚培养时为MSD 1.0 mg/L 2,4-D和MSD 2.0 mg/L IAA 2.0 mg/L KT。     

狗牙根颖果胚性愈伤组织的诱导和胚性细胞的超微结构及植株再生

以普通狗牙根[Cynodon dacylon(L.)Pers.cv.'Suncitv']颖果为外植体,以MS为基本培养基,外加浓度在2.0～6.0mg/L的2,4-D,能高频率地诱导出高质量的胚性愈伤组织,其中以4.0 mg/L为最佳.胚性愈伤组织最佳继代及分化的培养方法为:用MS 2,4-D 4.0mg/L继代1～2次,然后转入1/2 MS 2,4-D 2.0 mg/L中继代1～2次,再在无激素的1/2MS中光照培养10 d,最后在MS 6-BA 3.0 mg/L中诱导分化,分化成苗率达31.7%.经电镜观察发现,胚性愈伤组织结构紧密,细胞较小,内容物丰富,而非胚性愈伤组织结构疏松,细胞巨大,内含一大液泡,几无细胞器.     

荞麦组织培养及高频植株再生体系的建立

通过对荞麦(Fagopyrum esculentum Moench)不同外植体、不同激素配比的比较研究,建立了荞麦离体培养高效植株再生体系。荞麦子叶切段在含2．0 mg/L 2,4-D和1．0 mg/L 6-BA的MS培养基上愈伤组织诱导率为89．6％,而下胚轴切段在含2．0 mg/L 2,4-D和1．0-2．0 mg/L 6-BA MS培养基上愈伤组织诱导率高达100％。在2．0 mg／L 6-BA、0．1 mg,L IAA和1 mg／L KT的MS培养基上通过愈伤组织间接分化或外植体直接分化形成不定芽。来自子叶和下胚轴的愈伤组织的分化率分别为42．5％和73．6％,下胚轴的分化率明显高于子叶。将生长状态良好的不定芽转至含1．0 mg/L IBA和0．5mg/L NAA的1/2 MS培养基上生根,生根率达到100％。再生植株移栽到盆土中,成活率达91．6％,并且生长状态和特征均表现正常。     

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.