白胸苦恶鸟消化管的组织学观察

采用石蜡切片技术对白胸苦恶鸟(Amaurornis phoenicurus)的消化道进行了组织学观察.结果表明,食管皱襞发达,黏膜上皮为复层扁平上皮,食管腺发达,颈段多于胸段,黏膜肌层为一层纵肌,厚约0.06 ～0.26 mm.肌层为一层厚约0.19～0.27mm的环肌.腺胃被覆单层柱状上皮,固有层内有单管腺和复管腺两种腺体,单管腺仅深约0.11 ～0.20 mm;复管腺厚约1.19～1.26 mm,占管壁的77.8％ ～80.4％.肌胃的类角质层发达,厚约0.16～0.24 mm.肌胃腺呈管状,与类角质层突起形成皱襞.肌层发达,由内环外纵两层平滑肌构成.肠绒毛无分支和中央乳糜管,十二指肠绒毛长而密集,空肠绒毛呈细长指状,直肠绒毛长且呈叶状.十二指肠与直肠肠绒毛内有大量致密淋巴小结,盲肠绒毛短,肠腺少.     

环颈雉消化系统组织形态学观察

１９８９年４月至１９９０年４月作者对６只健康成年环颈雉消化系统组织采用常规方法制成显微和超薄切片。研究表明：环颈雉消化管的粘膜层，肌层和管状消化腺发达。食管为角化的覆层扁平上皮，角化层厚０．７２－０．８０μｍ，粘液腺丰富，腺细胞内充满粘原颗粒。腺胃内有发达的复管状腺和单管腺二种腺体；单管腺由颈粘液细胞、长柱状细胞和内充泌细胞组成。肌胃内有肌胃腺，无粘膜肌层。十二指肠绒毛长而密集且分支明显；无中央乳     

一雄性丹顶鹤消化系统组织形态学观察

常用常规方法制片，Ｈ．Ｅ染色，观察了一维性丹顶鹤的消化系统组织结构。食道壁厚，内具许多发达的纵行皱襞，粘液腺丰富。嗉囊壁薄，皱襞少而浅，淋巴细胞丰富聚集成团。腺胃由发达的复管状腺和单管状腺组成。肌胃内的单管状腺多９￣１３个聚成一束，肌层仅为环肌组成。肌胃内的单管状腺多９￣１３个聚成一束，肌层仅为环肌组成。十二指肠处的小肠腺发达，无十二指肠腺，肠绒毛稀疏、叶状。空肠绒毛长而密集，细长指状。回肠的小肠     

大鸨消化系统组织学观察

应用常规石蜡切片,H.E.染色,对3只大鸨消化系统组织结构进行了观察。结果表明,大鸨食管复层扁平上皮有化不明显,粘液腺十分丰富。腺胃内有发达的复管状腺和单管状腺,密集排列在胃壁内。腺胃乳头内有发达的粘液腺,开口于乳头顶部,复管状腺的集合窦则开口于粘液腺底部。肌胃粘膜内密布单管状腺,无粘膜肌。小肠内环肌发达,粘膜下层不明显,十二指肠处绒毛最高,分支最复杂,无十二指肠腺。盲肠前部具发达的绒毛,而中后部不明显,直肠绒毛发达,杯状细胞增多,盲肠与直肠粘膜下层较发达。肝、胰小叶界限不清。     

巴西彩龟消化道组织学的初步观察

巴西彩龟的消化道管壁由内向外依次由粘膜、粘膜下层、肌层和浆膜4层结构组成.食管、胃和大肠有纵行粘膜皱襞,小肠无皱襞但有绒毛.食管上皮和肠上皮为复层柱状上皮,胃上皮为单层柱状上皮.消化道粘膜固有层内分布有淋巴细胞,虽然淋巴细胞有聚集现象,但没有形成典型的淋巴小结.无食管腺和肠腺,虽然有胃腺但胃腺细胞分化不明显,说明巴西彩龟消化道的组织分化程度较低,在系统发育中处于较低等地位.     

版纳鱼螈消化道解剖学和组织学观察

对我国特有珍稀濒危两栖动物版纳鱼螈(Ichthyophis bannanicus)的消化道进行解剖和组织学观察.结果表明,版纳鱼螈消化道呈直管状,无盘曲;胃、肠分化明显,肠可分为十二指肠、空肠、大肠和直肠;黏膜上皮食管为复层柱状纤毛上皮,胃后段为单层柱状上皮,直肠为复层扁平上皮,其余均为复层柱状上皮;口咽腔黏膜含大量巨型杯状细胞,有单泡状颌间腺;食道中下段有团泡状食道腺;胃体部含大量单管状胃腺;十二指肠和空肠有单泡状肠腺,绒毛发达;口咽腔的黏膜下层不明显,食道和直肠的黏膜下层为疏松结缔组织,其余均为细密的结缔组织;肌层除口咽腔为骨骼肌外,其余均为内环外纵两层平滑肌,其中,在十二指肠和空肠的两肌层间有细密的结缔组织连接.     

西晨冠鹤消化管的组织学观察

选择西百鹤的食管、素囊、腺胃、肌胃、十二指肠、空肠、回肠等几部分进行组织学观察,目的为改进饲养方法和饲料配比提供理论依据。结果表明：西非冠鹤的消化管粘膜层粘膜上皮由复层扁平上皮渐变为单层柱状上皮,固有膜均发达,占膜肌在段而异。粘膜下层很薄甚至缺如。肌层为内环外纵,除食管外其它均为将膜。以上消化管的结构特点可能与西非冠鹤的生活习性有关。     

西非冠鹤消化管的组织学观察

选择西非冠鹤的食管、素囊、腺胃、肌胃、十二指肠、空肠、回肠等几部分进行组织学观察 ,目的为改进饲养方法和饲料配比提供理论依据。结果表明 :西非冠鹤的消化管粘膜层粘膜上皮由复层扁平上皮渐变为单层柱状上皮 ,固有膜均发达 ,粘膜肌层因段而异。粘膜下层很薄甚至缺如。肌层为内环外纵 ,除食管外其它均为浆膜。以上消化管的结构特点可能与西非冠鹤的生活习性有关。     

西藏蟾蜍消化系统组织学观察

对西藏蟾蜍的消化系统进行了组织学观察.消化道可以分为口腔、咽、食道、胃、十二指肠、回肠和直肠;肝脏和胰腺为消化腺.胃壁由黏膜层、黏膜下层、肌肉层和外膜组成.黏膜层中含有许多胃腺,但胃腺的颈部和腺体部不明显.肌肉层发达,有内环外纵两层平滑肌.小肠壁由黏膜层、黏膜下层、肌肉层和外膜组成,十二指肠的黏膜下层缺失.在黏膜层的固有膜中有管状肠腺.肝脏分为左、中、右3叶,肝小叶界限不明显.胰腺中的腺泡由腺细胞围成.     

秦岭滑蜥消化系统组织结构及消化管嗜银细胞观察

为揭示秦岭滑蜥(Scincella tsinlingensis)消化系统的基本特征,运用大体解剖与组织切片技术、Grimelius浸银法对其消化系统组织结构以及消化管嗜银细胞的分布、形态和密度进行了观察。除舌外,消化管的管壁分为黏膜层、黏膜下层、肌层和外膜。消化管各部分的差异主要在管壁厚度和黏膜皱襞数量。各段管壁厚度以胃幽门部最厚,达(221.03±5.94)μm,而十二指肠最薄,仅(63.59±1.17)μm。各段黏膜皱襞的形态和数量明显不同,空肠多达17~20个,其次为回肠和十二指肠,分别为15~17个和11~13个。此外,消化管各部分肌层的相对厚度及腺体的分布也存在差异。肝组织无典型的肝小叶分化,胰腺中胰岛不发达。在秦岭滑蜥的消化管中,锥形、椭圆形、圆形或不规则形的嗜银细胞广泛分布于固有膜和黏膜上皮细胞之间,胃体部的密度最高。上述结果表明,秦岭滑蜥消化系统结构与大多数爬行类相比,无明显差异。消化管中嗜银细胞分布、形态和密度可能与其在该物种中的功能有关。     

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.