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151.
Plasmids encoding foot-and-mouth disease virus VP1 epitopes elicited immune responses in mice and swine and protected swine against viral infection 总被引:20,自引:0,他引:20
VP1 is a capsid protein of foot-and-mouth disease virus (FMDV) and contains epitopes of the virus. Plasmids encoding two VP1 epitopes (amino acid residues 141-160 and 200-213) and a host-self immunoglobulin molecule were constructed to produce a new type of FMD DNA vaccine. Two plasmids, namely, pCEIM and pCEIS, containing mouse immunoglobulin (IgG) or swine IgG were subjected to immunogenicity testing in mice and swine, respectively. In mice administrated pCEIM in the abdomen using a genegun, both FMDV-specific T-cell proliferation and neutralizing antibodies were detected. In swine immunized with pCEIS at the back of the ear, immune responses were achieved after the second administration. Swine showed a T-cell proliferative response with a stimulation index (SI) of up to 8.1 and a neutralizing antibody response that was able to protect suckling mice from 10(2) LD(50) (lethal dose 50) FMDV challenge. To compare the immunogenicity of the DNA-based vaccine candidate, versus the protein-based vaccine candidates, a second group of swine was immunized with the protein F1-scIgG, which was encoded by the plasmid pCEIS. Injection with F1-scIgG elicited a T-cell proliferative response of SI < 1.7 and a neutralizing antibody response that protected suckling mice from up to 10(5) LD(50) FMDV challenge. In the challenge test, three of three swine immunized with pCEIS were fully protected from FMDV challenge. 相似文献
152.
Wang Z Samuelson J Clark CG Eichinger D Paul J Van Dellen K Hall N Anderson I Loftus B 《Molecular and biochemical parasitology》2003,129(1):23-31
Entamoeba invadens, a parasite of reptiles, is a model for the study of encystation by the human enteric pathogen Entamoeba histolytica, because E. invadens form cysts in axenic culture. With approximately 0.5-fold sequence coverage of the genome, we were able to get insights into E. invadens gene and genome features. Overall, the E. invadens genome displays many of the features that are emerging from ongoing genome sequencing efforts in E. histolytica. At the nucleotide level the E. invadens genome has on average 60% sequence identity with that of E. histolytica. The presence of introns in E. invadens was predicted with similar consensus (GTTTGT em leader A/TAG) sequences to those identified in E. histolytica and Entamoeba dispar. Sequences highly repeated in the genome of E. histolytica (rRNAs, tRNAs, CXXC-rich proteins, and Leu-rich repeat proteins) were found to be highly repeated in the E. invadens genome. Numerous proteins homologous to those implicated in amoebic virulence, (Gal/GalNAc lectins, amoebapores, and cysteine proteinases) and drug resistance (p-glycoproteins) were identified. Homologs of proteins involved in cell cycle, vesicular trafficking and signal transduction were identified, which may be involved in en/excystation and cell growth of E. invadens. Finally, multiple copies of a number of E. invadens genes coding for predicted enzymes involved in core metabolism and the targets of anti-amoebic drugs were identified. 相似文献
153.
We report a case of papillary carcinoma arising in a thyroglossal duct cyst, presenting with an anterior neck mass of a 31-year-old woman. The tumor was judged to be a primary lesion on the basis of intraoperative examination of the thyroid and pathologic findings of the mass. One year later, a small nodular mass in the left thyroid gland and lymph node enlargement of the right cervical lymph node were noted by follow-up imaging studies. Total thyroidectomy, right modified radical neck dissection and central neck dissection were performed. The thyroid gland revealed nodular hyperplasia without evidence of malignancy. On the other hand, the dissected neck lymph nodes revealed metastatic papillary carcinoma. Taken together, these findings suggested the tumor was a primary papillary carcinoma arising in the thyroglossal duct cyst. 相似文献
154.
TRIO amplification and abundant mRNA expression is associated with invasive tumor growth and rapid tumor cell proliferation in urinary bladder cancer 下载免费PDF全文
Zheng M Simon R Mirlacher M Maurer R Gasser T Forster T Diener PA Mihatsch MJ Sauter G Schraml P 《The American journal of pathology》2004,165(1):63-69
Studies by comparative genome hybridization have suggested that 5p amplification is related to tumor progression in urinary bladder cancer. In this study seven genes (TAS2R, ADCY2, DNAH5, CTNND2, TRIO, ANKH, and MYO10) located to 5p15.31-5p15.1 were analyzed by fluorescence in situ hybridization using a tissue microarray containing samples from tumors and cell lines with known 5p amplification by comparative genome hybridization. Amplification frequency was highest for TRIO, which maps to 5p15.2 and encodes a protein with a putative role in cell-cycle regulation. To further investigate the role of TRIO amplification in bladder cancer, a tissue microarray containing samples from 2317 bladder tumors was used for fluorescence in situ hybridization analysis. TRIO amplification was strongly associated with invasive tumor phenotype, high tumor grade, and rapid tumor cell proliferation (Ki67 LI) (P < 0.0001 each). Only 7 of 456 pTaG1/G2 tumors (1.5%) but 62 of 485 pT1-4 carcinomas (12.8%) had TRIO amplification. TRIO amplification was not associated with poor prognosis. Using a frozen bladder tumor tissue microarray RNA in situ hybridization confirmed that TRIO is up-regulated in amplified tumors. It is concluded that TRIO up-regulation through amplification has a potential role in bladder cancer progression. 相似文献
155.
血糖感应型胰岛素给药智能载体的研究进展 总被引:1,自引:0,他引:1
胰岛素控制释放高分子载体系统一直是国内外科技工作者的研究热点 ,迄今已经研究报道了多种具有不同工作原理的血糖感应型胰岛素给药智能载体。本文基于国内外大量研究文献 ,综述了血糖感应型胰岛素控制释放智能化高分子载体的研究进展。 相似文献
156.
Nam KW Chung J Choi SW Kim WE Sun K Min BG 《The International journal of artificial organs》2004,27(10):882-890
A pulsatile left ventricular assist device (LVAD) was used to support the aortic blood pumping function of an injured left ventricle, and as a result helped its recovery. It is important to observe a left ventricle's pumping status and to adjust the operating status of a LVAD to reduce the left ventricle's pumping load and thus to enhance its recovery. To observe the left ventricle's pumping status, an electrocardiogram (ECG) signal is generally used because it is a result of the natural heart's blood pumping function. In this paper, we describe the development of an ECG based counterpulsation control algorithm that prevents simultaneous aortic blood co-pumping by a left ventricle and a moving-actuator type pulsatile LVAD and as a result, reduces the natural heart's pumping load. In addition, to verify the algorithm's applicability for LVAD control we designed three ECG based automatic pump control algorithms that use a developed counterpulsation control algorithm. These algorithms control the operating status of a LVAD automatically and, at the same time, maintain a counterpulsing status. The results of in vitro experiments show that the counterpulsing effect between a left ventricle and a LVAD was successfully produced and that the newly designed automatic pump control algorithms met their own control purposes with a counterpulsing effect. 相似文献
157.
158.
Study on the metastatic mechanisms of human giant-cell lung carcinoma comparison between the strains C and D 总被引:4,自引:0,他引:4
Mei L Lezhen C Po Z Zheng G Yali L Nan L 《Asian Pacific journal of allergy and immunology / launched by the Allergy and Immunology Society of Thailand》1998,16(4):167-176
The biologic characteristics of the two human giant-cell lung carcinoma strains with high (strain D) and low metastatic potential (strain C) were studied, including karyotype of chromosome, intracellular free calcium ([Ca2+]i), morphologic changes of cell surface and the expression of nm23-H1, p53, ras, c-myc, c-erbB2, bcl-2 genes and PCNA. The correlation between different biologic features and the metastatic potential of the two strains was analyzed. We found: 1) Both strains had the karyotypic abnormality of -13, -14, -15, +20, +21 with seven same marker chromosomes. Only strain D had the karyotypic abnormality of +7, -17, -18, +X, 7p+; 2) [Ca2+]i of the strain C (984.7 +/- 573.8) and D (517.6 +/- 216.6) was significantly different (p < 0.05). The amplitude of intracellular calcium oscillations of strain C was lower than the one of strain D; 3) strain C had more villous-like protrusions on the cell surface, whereas strain D had more bubble-like protrusions; 4) The expression of nm23-H1 and p53 protein of strain C was all higher than that of strain D. The expression of PCNA of strain C was lower than strain D; 5) nm23-H1 mRNA levels of strain C was lower than that of strain D. We consider that the karyotype of chromosomes, intracellular free calcium, the structure of cell membrane and the expression of nm23-H1 gene, p53 gene, PCNA could be closely related to the metastatic potential of human giant-cell lung carcinoma. They could be used as the sign for judging whether the tumor will metastasize in clinical practice as well as in judging the prognoses of patients. 相似文献
159.
Missing data such as appropriateness ratings in clinical research are a common problem and this often yields a biased result. This paper aims to introduce the multiple imputation method to handle missing data in clinical research and to suggest that the multiple imputation technique can give more accurate estimates than those of a complete-case analysis. The idea of multiple imputation is that each missing value is replaced with more than one plausible value. The appropriateness method was developed as a pragmatic solution to problem of trying to assess "appropriate" surgical and medical procedures for patients. Cataract surgery was selected as one of four procedures that were evaluated as a part of the Clinical Appropriateness Initiative. We created mild to high missing rates of 10%, 30% and 50% and compared the performance of logistic regression in cataract surgery. We treated the coefficients in the original data as true parameters and compared them with the other results. In the mild missing rate (10%), the deviation from the true coefficients was quite small and ignorable. After removing the missing data, the complete-case analysis did not reveal any serious bias. However, as the missing rate increased, the bias was not ignorable and it distorted the result. This simulation study suggests that a multiple imputation technique can give more accurate estimates than those of a complete-case analysis, especially for moderate to high missing rates (30 - 50%). In addition, the multiple imputation technique yields better accuracy than a single imputation technique. Therefore, multiple imputation is useful and efficient for a situation in clinical research where there is large amounts of missing data. 相似文献
160.
Brain images produced on the EMI 7070 scanner exhibit a "cupping" artefact due to a combination of beam hardening and scatter effects. The magnitude of the artefact is assessed by statistically analysing a series of concentric regions of interest in the final image. Once the magnitude has been determined it can be subtracted from the image. While the result of the technique does not modify the clinical analysis of images it does increase the observer's appreciation of the image. Both the technique and clinical results are presented, and the implications of this type of reconstruction artefact removal discussed. 相似文献