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91.
JC病毒样颗粒可直接转运进入细胞核 总被引:2,自引:1,他引:1
目的探讨JC病毒(JCV)病毒样颗粒(VLP)是否可以直接转运进入细胞核。方法心用JCV主要外壳蛋白VP1体外表达、重组VIP,在其表面标记异硫氰基荧光素(FTTC),同时在其内部包裹荧光染料Cy3,感染培养的HeLa细胞和SVG细胞,荧光显微镜观察VLP入核转运。结果HeLa和SVG细胞感染包裹Cy3的FTTC-VLP时,FTTC与Cy3同时出现于细胞核内相同部位;而感染FTTC—VP1与Cy3混合物时,FTTC虽可在细胞核内检测到,但Cy3信号几乎消失。包裹Cy3的VIP用SDSPAGE展开,荧光显像后行考马斯亮蓝(CBB)染色,发现Cy3和VLP移行至不同部位,证明Cy3不能与VP1结合,提示VLP以完整的颗粒形式转运进入细胞核。应用包裹外源性DNA的VLP感染培养的HeLa和SVG细胞,发现包裹的DNA在细胞浆和细胞核内均可检测到,提示JCV入核过程与VIP相同。结论VLP可以不经裂解直接转运进入细胞核,JCV入核转运可能与VLP相同。 相似文献
92.
乙型肝炎病毒免疫逃避株表面抗原决定簇编码区的序列分析 总被引:2,自引:0,他引:2
应用聚合酶链反应(PCR)产物直接测序,在国内首次发现1例持续高滴度乙型肝炎表面抗原(HBsAg)和抗一HBs共存者携带的乙型肝炎病毒DNA第532位碱基A被G取代,推导其“a”决定簇中第126位苏氨酸被丙氨酸取代,提示该株“a”决定簇第一个结构环疏水性增加,由此可能导致其抗原性改变,而诱发免疫逃避株形成。 相似文献
93.
Treatment of chronic hepatitis B 总被引:3,自引:0,他引:3
A. S. F. Lok 《Journal of viral hepatitis》1994,1(2):105-124
SUMMARY. Chronic infection with the hepatitis B virus (HBV) is a major cause of worldwide morbidity and mortality. A large number of therapeutic approaches has been tried, including interferon (IFN), nucleoside analogues and immunomodulators. To date controlled clinical trials have shown that only IFN is of long-term value but many patients fail to respond to treatment. New approaches to treating patients with IFN-resistant hepatitis B are currently undergoing clinical and experimental evaluation, and it seems likely that new therapeutic agents will be available in the near future. 相似文献
94.
Detection of Epstein Barr virus in an hepatic leiomyomatous neoplasm in an adult human immunodeficiency virus 1-infected patient 总被引:5,自引:0,他引:5
S. Prévot J. Néris P. P. de Saint Maur 《Virchows Archiv : an international journal of pathology》1994,425(3):321-325
We report the first case of a human immunodeficiency virus (HIV)-related primary hepatic leiomyoma in an adult patient. The diagnosis was made at autopsy and confirmed by immunohistochemistry. Epstein Barr virus (EBV) was identified in tumour cells by in situ hybridization. Review of the literature revealed 13 cases of visceral myogenic tumours occuring in acquired immunodeficiency syndrome children, and only 2 cases in adults. One was a spinal epidural leiomyoma, the other multiple smooth muscle tumours of the colon and adrenal gland. This is the first report of EBV in smooth muscle neoplastic cells in an HIV-infected adult patient. 相似文献
95.
Serial sections of formalin-fixed, paraffinembedded blocks from two asymptomatic, non-AIDS cases of progressive multifocal leukoencephalopathy (PML) were stained with a double-label immunocytochemical method for detection of glial fibrillary acidic protein and JC virus (JCV) capsid proteins and with luxol fast blue/hematoxylin-eosin. In case 1 small, rounded lesions of about 1-mm diameter were seen within a restricted area in the posterior part of the superior frontal gyrus of both cerebral hemispheres, suggesting an early manifestation of the disease. Fully developed demyelinated lesions of the classical type with JCV-infected oligodendrocytes appeared in the white matter and along its border with the cortex. Lesswell-developed lesions, believed to be precursors to the fully developed ones, were seen in the gray and white matter. Of special interest were areas which contained small collections of enlarged, glial fibrillary acidic protein (GFAP)-positive astrocytes without capsid antigen and which seemed to lack destruction of myelin as judged from the appearance of matching serial sections stained for myelin. Large lesions in the brain of case 2 showed the well-known features of advanced PML. The close relation between some astrocytes and oligodendrocytes with viral antigen raises the possibility of early intercellular passage of virus. Vacuolation, seen within or near lesions in both cases, has previously been noted in the CNS infected by HIV, but not in PML. It is suggested that PML, a disease of both oligodendrocytes and astrocytes, may actually begin in astroglial cells which, under the influence of a restricted JCV infection, become reactive, express GFAP and pass on virus to the more highly susceptible oligodendrocytes with which they are in contact.Supported in part by a grant N.S.07596 from the National Institute of Neurological Disorders and Stroke. The work was carried out in the Laboratory of Experimental Neurophathology, NINDS, and in the Department of Pathology II, Karolinska Institute, Stockholm 相似文献
96.
聚合酶链反应检测尖锐湿疣皮损内人乳头瘤病毒 总被引:7,自引:0,他引:7
13个皮损组织取自13例尖锐湿疣(CA)患者,13例基底细胞上皮瘤(BCC)组织作为对照,用溴化钠液分离表真皮,从组织中提出的 DNA和溴化钠液分别用聚合酶链反应检测 HPV DNA。11例CA表皮中检出 HPV DNA,HPV6有7例,HPV11有4例。3例CA真皮中发现有HPV DNA,HPV6有2例,HPV11有1例。2例标本因溴化钠液被HPV污染未作统计。在BCC组织中未发现有HPV DNA。在某些CA真皮内含有 HPV DNA可以解释散发病例的复发性。 相似文献
97.
Dengue is a mosquito-borne viral disease caused by four antigenically distinct serotypes of dengue viruses (DENVs). This disease, which is prevalent in over a hundred tropical and sub-tropical countries of the world, represents a significant global public health problem. A tetravalent dengue vaccine capable of protecting against all four DENV serotypes has been elusive so far. Current efforts are focused on producing a tetravalent vaccine by mixing four monovalent vaccine components. In this work, we have utilized a discrete carboxy-terminal region of the major DENV envelope (E) protein, known as domain III (EDIII), which mediates virus entry into target cells and contains multiple serotype-specific neutralizing epitopes, to create a chimeric tetravalent antigen. This antigen derived by in-frame fusion of the EDIII-encoding sequences of the four DENV serotypes was expressed using a replication-defective recombinant human adenovirus type 5 (rAdV5) vaccine vector. This rAdV5 vector induced cell-mediated immune responses and virus-neutralizing antibodies specific to each of the four DENVs in mice. Interestingly, anti-AdV5 antibodies did not suppress the induction of DENV-specific neutralizing antibodies. We observed that anti-AdV5 antibodies in the sera of immunized mice could promote uptake of a rAdV5-derived reporter vector into U937 cells, suggesting that pre-existing immunity to AdV5 may in fact facilitate the uptake of rAdV5 vectored vaccines into antigen presenting cells. This work presents an alternative approach to developing a single component tetravalent vaccine that bypasses the complexities inherent in the currently adopted four-in-one physical mixture approach. 相似文献
98.
Cell culture-based influenza vaccine manufacturing is of growing importance. Depending on virus strains, differences in infection dynamics, virus-induced apoptosis, cell lysis and virus yields are observed. Comparatively little is known concerning details of virus–host cell interaction on a cellular level and virus spreading in a population of cells in bioreactors. In this study, the infection of MDCK cells with different influenza A virus strains in lab-scale microcarrier culture was investigated by flow cytometry. Together with the infection status of cells, virus-induced apoptosis was monitored. A mathematical model has been formulated to describe changes in the concentration of uninfected and infected adherent cells, dynamics of virus particle release (infectious virions, hemagglutinin content), and the time course of the percentage composition of the cell population. 相似文献
99.
Nuthapong Ukarapol Nirush Lertprasertsuk George J. Fuchs Lumduan Wongsawasdi Virat Sirisanthana 《Digestive endoscopy》2004,16(1):26-29
Objective: To evaluate the role of gastrointestinal (GI) endoscopy in human immunodeficiency virus (HIV)‐infected children with GI problems. Methods: From 1998 to 2002, we retrospectively reviewed all cases of HIV‐infected children presenting with GI problems in which an upper or lower GI endoscopy was indicated. The initial diagnostic endoscopic examination and any repeat endoscopic session leading to a new diagnosis were used in the data analysis. Tissue biopsies were obtained from all abnormal lesions and representative sites of normal‐appearancing GI mucosa. Results: Fourteen patients (median age: 22.5 months) underwent 23 sessions of GI endoscopy, including 10 esophagogastroduodenoscopy, nine colonoscopy and four flexible sigmoidoscopy. Chronic diarrhea was the most common indication, followed by lower GI bleeding, abdominal/retrosternal pain, dysphagia/odynophagia, and upper GI bleeding. Gross endoscopic abnormalities were observed in 78.3%; whereas histological inflammation and opportunistic pathogens were identified in 87% and 43.5%, respectively. Cytomegalovirus was the most common identified pathogen. Abnormal gross findings were significantly associated with histological inflammation and identification of pathogens (P = 0.006 and 0.046, respectively). Specific changes in medical management were made in 50% of cases as a result of endoscopic investigation. Conclusion: If non‐invasive investigations for HIV‐infected children with GI symptoms fail to establish a diagnosis, gastrointestinal endoscopy should be performed and often yields a positive result leading to changes in medical management. 相似文献
100.
质疑Frank—Starling心脏定律 总被引:4,自引:4,他引:0
心脏收缩释放的能量(作功)是心肌纤维长度(心室舒张末期容积,EDV)的函数,即Frank—Star一1ing(FS)心脏作功定律,被誉为心脏生理学中的“经典”理论。对此,笔者从各种不同角度进行了探讨:首先分析了Frank伸展离体心肌和Starling及其同事使用心肺制备做的实验与动物生理实际的差异,以及人们在实验中观测到的增加心肌前负荷引起收缩力增强的现象(FS现象),认为:①在正常生理条件下的动物体内,来自心脏以外的、如同心肺制备中那样人工控制心室充盈压力升高、引起EDV增加的那种血液的重力动力是不存在的。②另一方面,人为地增加前负荷,那是改变了心肌收缩时的外环境条件。③由此而激发出的FS现象,是心脏适应其外环境条件变化所作出的反应。④此种心肌收缩力增强的反应,需通过心肌细胞内部与收缩过程发生有关的心肌兴奋一收缩和化学一力学偶联等一系列生化机制(不恒定因素)方能得以实现。⑤根据他们实验中观测到的FS现象,在逻辑上不能得出前负荷这一心肌收缩时的外环境条件变化调控其作功的推论。换言之,所有的在实验中被激发出来的FS现象,都不足以成为支持FS心脏定律的证据。然后,引用国内外公认的计算心脏每搏射血作功(w)的生物物理学公式“w=P×(EDV—ESV)”,证明了w和EDV之间没有函数关系。根据心脏作功的医用物理学和生物数学的基本原理,笔者认为Frank—Starling心脏定律表达的不是心脏作功的规律。 相似文献