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排序方式: 共有904条查询结果,搜索用时 15 毫秒
1.
Expression of human immunodeficiency virus type 1gag gene using genetically engineered herpes simplex virus type 1 recombinants 总被引:1,自引:0,他引:1
Angela Rösen-Wolff Karl Raab Lothar Zöller Gholamreza Darai Josef Eberle Friedrich Deinhardt 《Virus genes》1990,4(4):325-337
Infectious herpes simplex virus type 1 (HSV-1) recombinants were constructed by inserting the cDNA sequence of the human immunodeficiency virus type 1 (HIV-1)gag gene (from nucleotide position 675 [SacI] to 3859 [Asp 718] of the cDNA sequences of HIV-1 strain BH-10) within the DNA sequences of theBamHI DNA fragment B of the genome of an apathogenic HSV-1 strain HFEM. This HSV-1 strain possesses a 4.1-kbp deletion within theBamHI DNA fragment B between 0.762 and 0.789 map units of the viral genome, which allows the insertion of at least 4 kbp of foreign genetic material into this particular region. The DNA sequences of the immediate early promoter (IE4) of HSV-1 that were inserted upstream from thegag gene were used as a promoter. The screening of 205 virus stocks derived from individual plaques revealed that 46 recombinant viruses harbor HIV-1gag-specific DNA sequences. However, it was found that only six of the recombinant viruses are able to express thegag gene product of HIV-1. This indicates that the ratio of the positive recombination events is about 2.9%. 相似文献
2.
Identification of a Thymidylate Synthase Gene within the Genome of Chilo Iridescent Virus 总被引:1,自引:0,他引:1
The thymidylate synthase (TS, EC 2.1.1.45) is essential for the de novo synthesis of dTMP in pro- and eucaryotic organisms. Consequently it plays a major role in the replication of the DNA genome of a cell or a DNA virus. The gene encoding the TS of Chilo iridescent virus (CIV) was identified by nucleotide sequence analysis of the viral genome and was mapped within the EcoRI CIV DNA fragments G and R. Computer assisted analysis of the DNA nucleotide sequence between the genome coordinates 0.482 and 0.489 revealed an open reading frame (ORF) of 885 nucleotides. This ORF was found to encode a polypeptide of 295 amino acid residues (33.9 kDa) that showed significant homologies to known TS of different species including mammals, plants, fungi, protozoa, bacteria, and DNA viruses. The highest amino acid homologies were found between the CIV-TS and the TS of herpesvirus ateles (54.0%), Saccharomyces cerevisiae (51.8%), herpesvirus saimiri (51.0%), rhesus monkey rhadinovirus (50.7%), mouse (50.5%), rat (50.2%), varicella-zoster virus (50.2%), equine herpesvirus 2 (50.0%), and the human TS (48.4%). The CIV-TS contains six amino acid domains that are highly conserved in the TS of other species. Within these domains the major amino acid residues are present for which a functional role has been reported. The CIV-TS was found to be more closely related to the TS of eucaryotes than to the TS of procaryotes indicating the phylogenetic origin of the CIV-TS gene. The identification of a TS gene in the genome of CIV is the first report of a viral TS that is not encoded by a herpesvirus or a bacteriophage. 相似文献
3.
Ehteshami G Singh A Coryell G Massia S He J Raupp G 《Journal of biomaterials science. Polymer edition》2003,14(10):1105-1116
Photosensitive benzocyclobutene (photo-BCB) is a class of polymers with the trade name Cyclotene. The photoimagable property of Cyclotene makes it suitable for the manufacture of microelectronic devices. The motivation behind this study is that we see an exciting application of photo-BCB as substrates in implantable microelectronic biomedical devices due to several desirable properties distinctive from other polymer materials. To our knowledge, however, photo-BCB has never been tested for biomedical implant applications, as evidenced by the lack reported data on its biocompatibility. This study takes the first step towards assessing photo-BCB biocompatibility by evaluating the cytotoxicity and cell adhesion behavior of Cyclotene 4026 coatings exposed to monolayers of glial and fibroblast cells in vitro. It can be concluded from these studies that photo-BCB films deposited on silicon wafers using microfabrication processes did not adversely affect 3T3 fibroblast and T98-G glial cell function in vitro. We also successfully rendered photo-BCB films non-adhesive (no significant fibroblast or glial cell adhesion) with surface immobilized dextran using methods developed for other biomaterials and applications. Future work will further develop prototype photo-BCB microelectrode devices for chronic neural implant applications. 相似文献
4.
Olle Ringdén Marie Schaffer Katarina Le Blanc Ulla Persson Dan Hauzenberger Mohammad R Abedi Olle Olerup Per Ljungman Mats Remberger 《Biology of blood and marrow transplantation》2004,10(2):128-134
The aim of this study was to identify significant prognostic factors by using unrelated genomically HLA-A, -B and -DRB1-identical donors. Such data could help to choose the best donor. We studied 136 consecutive patients with hematologic malignancies and a median age of 32 years (range, 0-55 years) who received hematopoietic stem cell transplantation. Bone marrow grafts were given to 83 and peripheral blood stem cells to 53 patients. The cumulative incidence of grade II to IV acute graft-versus-host disease (GVHD) was 30% and of chronic GVHD was 54%. At 5 years, the overall transplant-related mortality (TRM) was 34%, and patient survival was 50%. In Cox multivariate analysis, 32 potential risk factors were analyzed. Monoclonal antibody OKT-3 during conditioning was correlated with grade II to IV acute GVHD, chronic GVHD, and TRM. HLA-DP mismatch was associated with poor TRM and poor survival. Cytomegalovirus-seropositive patients with a seronegative donor had a decreased leukemia-free survival. Five-year TRM was 14% with no risk factor, 38% with 1 risk factor, and 87% with 2 risk factors. The 5-year survival was 72%, 48%, and 30% with 0, 1, and 2 risk factors, respectively. We concluded that unrelated hematopoietic stem cell transplantation may be improved if an optimal donor and immunosuppression are chosen. 相似文献
5.
Hans-Jürgen Rode Joachim Jakob Bugert Michaela Handermann Paul Schnitzler Roland Kehm Waltraud Janssen Hajo Delius Gholamreza Darai 《Virus genes》1994,9(1):61-75
The complete DNA nucleotide sequence of theEcoRI DNA fragment N (0.235 to 0.258 viral map units) of equine herpes virus type 2 (EHV-2) strain T400/3 was determined. This DNA fragment comprises 4237 bp with a base composition of 55.23% G+C and 44.77% A+T. Nineteen open reading frames (ORFs) of 50-287 amino acid (aa) residues were detected. ORF number 10 is located between the nucleotide position 2220 and 2756 coding for a protein of 179 amino acid residues. This protein shows significant homology to the cytokine synthesis inhibitory factor (CSIF; interleukin 10) of human (76.4%) and mouse (68.5%), and to the Epstein-Barr virus (EBV) protein BCRF1 (70.6%). The existence of an interleukin 10 (IL-10) analogous gene within the genome of the EHV-2 was confirmed by screening the genome of nine EHV-2 strains using specific oligonucleotide primers corresponding to the 5 and 3 region of this particular gene by polymerase chain reaction. In all experiments an 870 bp DNA product was amplified. The specifity of the amplified DNA fragments obtained from individual EHV-2 strains was confirmed by DNA-DNA hybridization experiments. The DNA sequence analysis of the amplified DNA products of the EHV-2 strain LK was carried out. This analysis revealed the identity of the corresponding IL-10 gene (540 bp) of this strain to the IL-10 gene of EHV-2 strain T400/3. The presented data indicate that the EHV-2 genome harbors a viral interleukin 10-like gene. This is further evidence that the IL-10 gene can be present in the genomes of members of the Herpesviridae family. 相似文献
6.
The family Herpesviridae comprises at least 100 herpesviruses. Numerous human and animal pathogenic herpesviruses have been identified so far, including Cercopithecine herpesvirus 1 (CeHV-1). This virus is a member of the subfamily Alphaherpesvirinae and is the most hazardous herpesvirus to man. CeHV-1 is also known as B-virus or monkey B virus and as Herpesvirus simiae. In order to gain more genetic information, the viral DNA polymerase (DPOL) gene was identified using polymerase chain reaction (PCR) and DNA nucleotide sequence analysis. The deduced amino acid sequence contains the motifs and signatures that are typical for the B-family of DPOLs. The DPOL gene of CeHV-1 was found to be a suitable target for the specific and rapid identification of the Cercopithecine herpesvirus 1 infection by PCR technology. Comparative analysis of the DNA sequences of the DPOL gene loci of CeHV-1, Human herpesvirus 1 and 2 (HHV-1 and HHV-2), and other herpesviruses was carried out for determination of unique genomic regions of the individual DPOL genes. A primer set of 12 primers was used for screening the DNA of CeHV-1, HHV-1, and HHV-2 by detailed PCR. It was found that six out of twelve primer combinations are able to detect specifically the CeHV-1 genome without cross reactivity with the genome of HHV-1 and/or HHV-2. The specificity of the individual amplified DNA fragments was confirmed by DNA nucleotide sequence analysis. The results of these studies indicate that the six primer combinations of the specific CeHV-1 DPOL primer set is the method of choice for a rapid, precise and specific identification of a CeHV-1 infection by PCR. Due to the fact that this specific CeHV-1 DPOL primer set does not amplify any DNAs of HHV-1 or HHV-2 genome this technology is stressing and can be successfully used unlimited and more credible in all laboratories with PCR technical facility routinely for detection of a CeHV-1 infection in vivo or in vitro.The GenBank Accession No. of the sequence of DNA polymerase gene of Cercopithecine herpesvirus 1 (CeHV-1) reported in this study is AY568415, DPOL protein ID AAT67222; nuclear phosphoprotein ID AAT67223 相似文献
7.
Differential expression of FIZZ1 and Ym1 in alternatively versus classically activated macrophages 总被引:10,自引:0,他引:10
Raes G De Baetselier P Noël W Beschin A Brombacher F Hassanzadeh Gh G 《Journal of leukocyte biology》2002,71(4):597-602
Alternatively activated macrophages (aaMphi) display molecular and biological characteristics that differ from those of classically activated macrophages (caMphi). Recently, we described an experimental model of murine trypanosomosis in which the early stage of infection of mice with a Trypanosoma brucei brucei variant is characterized by the development of caMphi, whereas in the late and chronic stages of infection, aaMphi develop. In the present study, we used suppression subtractive hybridization (SSH) to identify genes that are expressed differentially in aaMphi versus caMphi elicited during infection with this T. b. brucei variant. We show that FIZZ1 and Ym1 are induced strongly in in vivo- and in vitro-elicited aaMphi as compared with caMphi. Furthermore, we demonstrate that the in vivo induction of FIZZ1 and Ym1 in macrophages depends on IL-4 and that in vitro, IFN-gamma antagonizes the effect of IL-4 on the expression of FIZZ1 and Ym1. Collectively, these results open perspectives for new insights into the functional properties of aaMphi and establish FIZZ1 and Ym1 as markers for aaMphi. 相似文献
8.
Khoobi M Emami S Dehghan G Foroumadi A Ramazani A Shafiee A 《Archiv der Pharmazie》2011,344(9):588-594
Coumarin and benzothiazole scaffolds can be found in a number of natural or synthetic antioxidants. In an effort to develop a novel radical scavenger and potential antioxidant, a series of coumarin derivatives containing 2‐methylbenzothiazoline motif and related compounds was synthesized and evaluated for their DPPH (1,1‐diphenyl‐2‐picrylhydrazyl) and ABTS?+ (2,2′‐azinobis(3‐ethylbenzothiazoline‐6‐sulfonic acid) radicals scavenging activities. Among them, 7‐hydroxy‐3‐(2‐methyl‐2,3‐dihydrobenzo[d]thiazol‐2‐yl)‐2H‐chromen‐2‐one ( 3e ) has shown a significant free radical scavenging activity. From the structure–activity point of view, it was found that phenolic coumarin ring and benzothiazoline moiety in target compounds may contribute to the scavenging activity against free radicals. 相似文献
9.
The inhibitory effects of Zataria multiflora essential oil on nitric oxide (NO) and hydrogen peroxide (H2O2) production were examined in human monocytes cultured in the presence of 20 mM glucose. Z. multiflora essential oil was extracted by water-distillation and then analyzed by GC–MS. Carvacrol (29.2%), thymol (25.4%), p-cymene (11.2%), linalool (9.6%) and γ-terpinene (8%) were the main components detected in the essential oil. Cells cultured in the presence of 20 mM glucose showed an increase in NO and H2O2 production as well as NO synthase (NOS) and NADH oxidase (NOX) activities compared to cells cultured in the presence of 5 mM glucose. Pretreatment with Z. multiflora essential oil, carvacrol and thymol reduced NO and H2O2 production as well as NOS and NOX activities in those cells cultured in the presence of 20 mM glucose. However, p-cymene, linalool and γ-terpinene did not show any such activities. Accordingly, it was concluded that Z. multiflora can reduce oxidative stress and can be used in the therapy of oxidative damage accompanying hyperglycemia and some inflammatory conditions. 相似文献
10.
目的:评估传统与欠矫手术治疗部分调节性内斜视患者的效果。
方法:将25例具有部分调节性内斜视和正常AC/A的患者随机分为两组,其中13例患者接受传统手术治疗,其余12例患者接受欠矫手术治疗。传统手术是基于远距远视完全矫正所测量的偏差上,而欠矫手术比传统手术标准低20%。所有患者均进行对称性双眼内直肌后退术,术后随访6mo。
结果:术后6mo,传统组与欠矫组手术成功率分别为46%和91%(成功标准定义为通过近距和远距远视的完全矫正斜视≤8^△)。传统组和欠矫组的手术过矫率分别为54%和9%,两组间差异有统计学意义(P〈0.05)。没有残余内斜视。手术成功率或欠矫率与患者的年龄、术前等效球镜均值、术前眼偏斜量无相关性。
结论:对于具有正常AC/A的部分调节性内斜视患者,欠矫的双眼内直肌后退术成功率较高,过矫率较低。 相似文献