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71.
72.
P Spruell ; JJ Moulds ; M Martin ; RO Gilcher ; PB Howard ; OO Blumenfeld 《Transfusion》1993,33(10):848-851
The serum of EH reacted with all red cells (RBCs) except her own, ficin- or trypsin-treated red cells, and En(a-) red cells. This reactivity defined an anti-EnaTS specificity. The red cells of the proposita typed as M-N+S-S+, Vw+Mur-Hil-Hut-Anek-Lane-, Wr(a-b+), EnaKT+. Red cells of five relatives were Vw+ and positive with her serum. Titration studies suggest that EH is genetically an MiI homozygote and that her Vw+ relatives are MiI heterozygotes. There is no history of consanguinity. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting studies have agreed with the serologic observations. A variant sialoglycoprotein of faster mobility than normal glycoprotein A, but no normal glycoprotein A, was detected on her red cells. Treatment with N-glycanase did not alter the mobility, which indicated that there was no N-glycosylation of residue 26. These findings are in agreement with the reported properties of the Mi.I-specific glycoprotein A. The relatives' Vw+ red cells showed the variant sialoglycoprotein and normal glycoprotein A. EH appears to be the first reported MiI homozygote. 相似文献
73.
张建军 《中国组织工程研究与临床康复》2007,11(31):6228-6232
目的:观察微囊化转大鼠脑啡肽原基因(pENK)细胞移植对慢性脊神经压榨性损伤大鼠的镇痛效应.
方法:实验于2006-03/2007-04在郑州大学医学重点实验室完成.①实验方法:通过反转录-聚合酶链反应技术可获得大鼠pENK基因,Hind Ⅲ,ClaⅠ双酶切后,同相应双酶切的pLNCX2载体大片段连接,构建成pENK基因反转录病毒载体pLNCX2-Enk,然后用脂质体法将该载体转染PT67细胞,G418筛选,获得携带pENK基因高滴度反转录病毒产毒细胞系.用海藻酸钠-多聚赖氨酸-海藻酸钠微囊包埋后,进行体外培养,定期检测微囊化细胞活性和pENK分泌量变化.同时,将转基因细胞移植于慢性脊神经压榨性损伤大鼠的蛛网膜下腔.②实验分组:SD大鼠60只,其中53只按照Bennett和Xie法制作大鼠慢性左侧坐骨神经压迫性损伤模型,其中42只造模成功.术后1周,将动物按随机数字表法分为3组,每组16只:微囊化转基因细胞移植组、空囊移植组和阴性对照组.微囊化转基因细胞移植组、空囊移植组分别植入微囊化细胞悬液80 μL(约300个微囊)、空微囊悬液80 μL(约300个空囊),阴性对照组不注射任何悬液.③实验评估:术后2周和8周行甲醛实验,在大鼠一侧后爪掌侧皮下注射体积分数为0.05的甲醛50 μL,观察其注射后1 h内的痛反应.采用Abbott等所推荐的以缩腿及舔爪时间之和作为行为学反应的指标.注射甲醛后,立即记录大鼠1 h内每5 min的缩腿及舔爪时间.
结果:①术后2周甲醛实验:空囊移植组第一时相的急性痛阶段(注射后5 min)和第二时相的慢性痛阶段(注射后41~45 min)大鼠的缩腿及舔爪时间都少于微囊化转基因细胞移植组(P<0.01).而在静息期,3组大鼠的缩腿及舔爪时间差异无显著性意义(P>0.05).②术后8周甲醛实验:3组大鼠的痛觉行为都呈明显的双时相反应.除了静息期(注射后5~15 min),微囊化转基因细胞移植组在各时间点上大鼠的缩腿及舔爪时间均低于空囊移植组(P<0.05).微囊化转基因细胞移植组大鼠的缩腿及舔爪时间在第一时相的急性痛阶段和第二时相的慢性痛阶段都低于空囊移植组(P<0.05).
结论:微囊化转pENK基因细胞移植对慢性神经痛大鼠有一定的镇痛作用,有望成为运动员慢性疼痛治疗的新方法. 相似文献
74.
JJ Korelitz ; AE Williams ; MP Busch ; TF Zuck ; HE Ownby ; LJ Matijas ; DJ Wright 《Transfusion》1994,34(10):870-876
BACKGROUND: Most blood centers utilize a confidential unit exclusion (CUE) process, intended to reduce the risk of transfusion-associated infectious diseases by allowing high-risk donors confidentially to exclude their blood from use for transfusion. The effectiveness of this method remains controversial. STUDY DESIGN AND METHODS: Confirmatory or supplemental test results for antibodies to human immunodeficiency virus, human T-lymphotropic virus type I, and hepatitis C virus, as well as hepatitis B surface antigen and syphilis and screening test results for antibodies to hepatitis B core (antigen) and alanine aminotransferase levels were obtained for approximately 1.8 million units donated during 1991 and 1992 at five blood centers within the United States. The prevalences of these infectious disease markers in units that the donors confidentially excluded (CUE+) and units that the donors did not exclude (CUE-) were calculated and examined within demographic subgroups. RESULTS: Units that were CUE+ were 8 to 41 times more likely to be seropositive for antibodies to human immunodeficiency virus and hepatitis C virus, hepatitis B surface antigen, and syphilis and three to four times more likely to react for antibody to hepatitis B core (antigen) or to have elevated alanine aminotransferase levels than units that were CUE- (p < 0.001). The positive predictive value of CUE (the percentage of CUE+ units that were confirmed seropositive for any marker) was 3.5 percent, and the sensitivity of CUE (the percentage of confirmed-seropositive units that were CUE+) was 2.3 percent. CONCLUSION: The current CUE process has low sensitivity and apparently low positive predictive value, and in many cases, it appeared that donors misunderstood it. Yet, CUE was not a “random process,” as CUE+ units were more likely to be seropositive for any infectious disease marker than CUE- units. This suggests that efforts to improve the CUE system may be warranted. As risk factors for transfusion-transmitted infection become more difficult to identify by history-based screening, however, such efforts may have limited effect. 相似文献
75.
The mouse monoclonal antibody M2A1 of IgG1 class, which is highly specific for blood group M antigen, was obtained and characterized by means of hemagglutination, enzyme-linked immunosorbent assay, immunoblotting, and inhibition assays. The use of modified M glycoprotein preparations for inhibition tests and of variant McN and Henshaw red cell membranes for immunoblotting showed that M2A1 recognized an epitope including the NH2-terminal serine and sialic acid residues of glycophorin A, whereas the fifth glycine residue was not involved. The reactivity of the antibody with M antigen was distinctly dependent on ionic strength and pH; the optimum was at pH 8 to 9. The alpha-amino group of terminal serine residue was not necessary for the reaction with M2A1 antibody, and the results obtained suggested that the positive charge of this group contributed to decreasing antigen-antibody reactions at pH below 8. The reaction of the antibody with blood group N antigen was not detectable in any of the assays used. 相似文献
76.
The effectiveness of the confidential unit exclusion (CUE) procedure recommended by the Food and Drug Administration has been questioned by the blood banking community. The purpose of this study was to determine whether donors were informing the blood center correctly regarding the disposition (transfuse or do not transfuse) of their donated blood. A letter explaining the confidential study and requesting permission to send the participant a questionnaire noting his or her self-exclusion choice was mailed to 230 donors who had chosen transfuse and 276 donors who had chosen do not transfuse. After consent was obtained, participants were sent a second packet and asked to indicate whether they had chosen correctly and, if not, to identify reasons for that incorrect choice. A seven-word terminology quiz made up of words from the CUE form was also enclosed. All participants who had chosen transfuse indicated that this was the correct choice. Approximately 50 percent of those who had chosen do not transfuse indicated that this was an incorrect choice; the most common reason was that "I was not paying attention." The most frequently misunderstood term was "confidential." Donors who chose do not transfuse had a significantly higher rate of error on the terminology quiz (p less than 0.01) than did those who chose transfuse. 相似文献
77.
Sini Nurmenniemi Teemu Sinikumpu Ilkka Alahuhta Sirpa Salo Meeri Sutinen Markku Santala Juha Risteli Pia Nyberg Tuula Salo 《The American journal of pathology》2009,175(3):1281-1291
Carcinoma cell invasion is traditionally studied in three-dimensional organotypic models composed of type I collagen and fibroblasts. However, carcinoma cell behavior is affected by the various cell types and the extracellular matrix (ECM) in the tumor microenvironment. In this study, a novel organotypic model based on human uterine leiomyoma tissue was established and characterized to create a more authentic environment for carcinoma cells. Human tongue squamous cell carcinoma cells (HSC-3) were cultured on top of either collagen or myoma. Organotypic sections were examined by immunohistochemistry and in situ hybridization. The maximal invasion depth of HSC-3 cells was markedly increased in myomas compared with collagen. In myomas, various cell types and ECM components were present, and the HSC-3 cells only expressed ECM molecules in the myoma model. Organotypic media were analyzed by radioimmunoassay, zymography, or Western blotting. During carcinoma cell invasion, matrix metalloprotease-9 production and collagen degradation were enhanced particularly in the myoma model. To evaluate the general applicability of the myoma model, several oral carcinoma, breast carcinoma, and melanoma cell lines were cultured on myomas and found to invade in highly distinct patterns. We conclude that myoma tissue mimics the native tumor microenvironment better than previous organotypic models and possibly enhances epithelial-to-mesenchymal transition. Thus, the myoma model provides a promising tool for analyzing the behavior of carcinoma cells.Tumor growth and invasion are not just determined by the malignant tumor cells, but instead various cell types and the extracellular matrix (ECM) of the tumor microenvironment affect the outcome.1 Particularly, fibroblasts have many prominent roles in the cancer progression. In fact, in many carcinomas, the majority of the stromal cells are fibroblasts that possess myofibroblastic characteristics and are called cancer-associated fibroblasts. They produce ECM molecules, proteases, growth factors, and chemokines that crucially affect the carcinoma cell behavior.2,3 In this context, the organotypic three-dimensional skin model developed by Fusenig et al4 replicates the in vivo situation more closely in vitro than the two-dimensional cell culture experiments. The model allows studying of carcinoma cell invasion in three-dimensional collagen gel embedded with fibroblasts. The degree of invasion can also be quantitatively analyzed.5,6 However, this kind of organotypic model remains somewhat artificial due to the lack of other cell types besides fibroblasts and ECM components that are present in vivo. In addition to the carcinoma cells and fibroblasts, endothelial and inflammatory cells, as well as several ECM molecules, are known to contribute to the tumor growth. The induction of angiogenesis, recruitment of inflammatory cells, and increased turnover of ECM components result in tumor progression.7,8 Therefore, we wished to determine whether real human tissue can be used in the organotypic method to provide a more natural stroma-like environment for studying carcinoma cell invasion. We used uterine leiomyoma tissue, which mainly consists of smooth muscle actin (SMA)-positive cells and collagens.9 The existence of various additional cell types and proteins in the myoma tissue was characterized, and the invasiveness of malignant human tongue squamous cell carcinoma cells (HSC-3) into this novel myoma organotypic culture was measured by different methods and compared with the traditional collagen organotypic model. To test the general applicability of the myoma model, the invasion patterns of various cell lines were examined in myoma and collagen organotypic cultures. 相似文献
78.
JJ Rainey P Bhatnagar CF Estivariz S Durrani M Galway H Sandhu S Bahl H Jafari J Wenger 《Bulletin of the World Health Organization》2009,87(12):955-959
Problem
Poliovirus transmission remained a public health challenge in western Uttar Pradesh, India in late 2005 and early 2006. In 2006, the India Expert Advisory Group for Polio Eradication concluded that, given the peak incidence of polio among children 6 to 12 months of age, a targeted birth dose of oral polio vaccine may be necessary to interrupt intense poliovirus transmission in high risk areas.Approach
The Government of Uttar Pradesh, the National Polio Surveillance Project and the United Nations Children’s Fund (UNICEF) implemented a pilot birth-dose project aimed at identifying and vaccinating all newborns with a dose of oral polio vaccine within 72 hours of birth in an effort to evaluate operational feasibility and potential impact on population immunity.Local setting
The project was piloted in Moradabad district: zone 7 in Moradabad City (urban setting), Kunderki block (rural setting) and in select birthing hospitals.Relevant changes
Between July 2006 and February 2007, 9740 newborns were identified, of which 6369 (65%) were vaccinated by project personnel within 72 hours of birth. Project coverage (for total newborns vaccinated) ranged from 39% (in zone 7) to 76% (in Kunderki block) of the estimated number of newborns vaccinated during previous supplemental immunization activities.Lessons learned
Birth-dose coverage among newborns was lower than expected. Expansion costs were estimated to be high, with marginal impact. The project, however, provided opportunities to strengthen newborn tracking systems which have increased the number of newborns and young infants vaccinated during supplemental immunization activities and enrolled in routine programmes. 相似文献79.
A Levy Bencheton JM Berenger P Del Giudice P Delaunay F Pages JJ Morand 《Journal of the European Academy of Dermatology and Venereology》2011,25(5):599-602
Background Bedbugs (Cimex lectularius) have been feeding on sleeping human beings since prehistory. In Europe, bed bugs were common and endemic until World War II when improved body and home hygiene, and widespread use of insecticides led to almost complete eradication. Current evidence indicates that bedbugs are making a comeback in Europe, USA, Canada and Australia. In our practice in Southern France, we observed several cases within a period of only 1 year. Objectives Based on this experience, we conducted an epidemiological study to evaluate the status of bedbugs in France. Methods During summer 2009, we mailed a short questionnaire to all hospital professors in the CEDEF (Collège des Enseignants de Dermatologie de France) asking four questions: number of suspected diagnosis of bedbugs in the year 2009, and number of certain positive diagnosis, difficulties in treatment, use of a pest control professional for treatment, and finally personal opinion on actual incidence of bedbugs, compared with past years. Results Of the 84 questionnaires sent, there were only 26 responses despite two reminders. The responses were predominantly southern France, probably as a result of intensive immigration and increased travel and trade. Difficulties encountered during diagnosis and treatment are also mentioned. Utilizing the services of entomological experts and pest control professionals is essential. Conclusions France has the same experience regarding the resurgence of bedbugs as several European countries, USA, Canada and Australia, especially the southern regions. This emerging health problem has to be known by dermatologists. A national programme has been launched in France to assess actual incidence and study C. lectularius‐ related diseases. 相似文献
80.