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31.
Correlation between recent thymic emigrants and CD31+ (PECAM-1) CD4+ T cells in normal individuals during aging and in lymphopenic children 总被引:1,自引:0,他引:1
Junge S Kloeckener-Gruissem B Zufferey R Keisker A Salgo B Fauchere JC Scherer F Shalaby T Grotzer M Siler U Seger R Güngör T 《European journal of immunology》2007,37(11):3270-3280
CD31(+)CD45RA(+)RO(-) lymphocytes contain high numbers of T cell receptor circle (TREC)-bearing T cells; however, the correlation between CD31(+)CD4(+) lymphocytes and TREC during aging and under lymphopenic conditions has not yet been sufficiently investigated. We analyzed TREC, telomere length and telomerase activity within sorted CD31(+) and CD31(-) CD4(+) lymphocytes in healthy individuals from birth to old age. Sorted CD31(+)CD45RA(+)RO(-) naive CD4(+) lymphocytes contained high TREC numbers, whereas CD31(+)CD45RA(-)RO(+) cells (comprising < or =5% of CD4(+) cells during aging) did not contain TREC. CD31(+) overall CD4(+) cells remained TREC rich despite an age-related tenfold reduction from neonatal (100 : 1000) to old age (10 : 1000). Besides a high TREC content, CD31(+)CD45RA(+)RO(-)CD4(+) cells exhibited significantly longer telomeres and higher telomerase activity than CD31(-)CD45RA(+)RO(-)CD4(+) cells, suggesting that CD31(+)CD45RA(+)RO(-)CD4(+) cells represent a distinct population of naive T cells with particularly low replicative history. To analyze the value of CD31 in lymphopenic conditions, we investigated six children after allogeneic hematopoietic stem cell transplantation (HSCT). Reemerging overall CD4(+) as well as naive CD45RA(+)RO(-)CD4(+) cells predominantly expressed CD31 and correlated well with the recurrence of TREC 5-12 months after HSCT. Irrespective of limitations in the elderly, CD31 is an appropriate marker to monitor TREC-rich lymphocytes essentially in lymphopenic children after HSCT. 相似文献
32.
Richard K. Englehardt Brent M. Nowak Michael V. Seger Frank D. Duperier 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2014,18(3)
Background and Objectives:
Aerosolized droplets of blood can travel considerable distances on release of intra-abdominal pressure during laparoscopic surgery. This creates an environmental hazard for members of the surgical team. This study describes and provides a method of measurement of aerosolized blood contamination during evacuation of the pneumoperitoneum in laparoscopic surgery.Methods:
Samples were measured by removing a trocar from the abdomen while a pneumoperitoneum of 15 mm Hg was present. A white poster board was placed 24 inches above the incision to catch the released blood spatter. By use of machine vision, luminol fluorescence, and computerized spatial analysis, data from the boards were recorded, analyzed, and scored based on the distance, size, and quantity of particulate contamination.Results:
We analyzed 27 boards. Spatter was present on every board. The addition of luminol to the boards increased the amount of visible spatter. Most tests created <1000 blood spatters. Fluids are typically ejected as a fine mist. Every test included at least 1 blood spatter. The range of the average blood spatter size was 0.53 × 10–3 to 7.11 × 10–3 sq in. The amount of spatter detected did not show any apparent correlation with the patient''s body mass index, the estimated blood loss, or the type of operation performed.Conclusions:
Evacuation of the pneumoperitoneum during laparoscopic surgery results in consistent contamination. Most blood spatter is not visible to the naked eye. Our results suggest that all surgical participants should wear appropriate protective barriers and conscious measures should be undertaken to prevent environmental contamination during pneumoperitoneal evacuation. 相似文献33.
R Seger N G Ahn T G Boulton G D Yancopoulos N Panayotatos E Radziejewska L Ericsson R L Bratlien M H Cobb E G Krebs 《Proceedings of the National Academy of Sciences of the United States of America》1991,88(14):6142-6146
Microtubule-associated protein 2 kinase (MAP kinase), which exists in several forms, is a protein serine/threonine kinase that participates in a growth factor-activated protein kinase cascade in which it activates a ribosomal protein S6 kinase (pp90rsk) while being regulated itself by a cytoplasmic factor (MAP kinase activator). Experiments with recombinant MAP kinase, ERK2, purified from Escherichia coli in a nonactivated form revealed a self-catalyzed phosphate incorporation into both tyrosine and threonine residues. Another MAP kinase, ERK1, purified from insulin-stimulated cells also autophosphorylated on tyrosine and threonine residues. Autophosphorylation of ERK2 correlated with its autoactivation, although both autophosphorylation and autoactivation were slow compared to that occurring in the presence of MAP kinase activator. Therefore, we propose that autophosphorylation is probably involved in the MAP kinase activation process in vitro, but it may not be sufficient for full activation. The specificity toward tyrosine and threonine residues indicates that the MAP kinases ERK1 and ERK2 are members of a group of kinases with specificity for tyrosine as well as serine and threonine residues. 相似文献
34.
Anelia Dietmann Bernd Wallner Rebekka K?nig Katrin Friedrich Bettina Pfausler Florian Deisenhammer Andrea Griesmacher Christoph Seger William Matuja Louise JilekAall Andrea S Winkler Erich Schmutzhard 《African health sciences》2014,14(2):434-438
Background
Nodding syndrome (NS) is a seemingly progressive epilepsy disorder of unknown underlying cause. We investigated association of pyridoxal-phosphate serum levels and occurrence of anti-neuronal antibodies against N-methyl-D-aspartate (NMDA) receptor and voltage gated potassium channel (VGKC) complex in NS patients.Methods
Sera of a Tanzanian cohort of epilepsy and NS patients and community controls were tested for the presence of anti-NMDA-receptor and anti-VGKC complex antibodies by indirect immunofluorescence assay. Furthermore pyridoxal-phosphate levels were measured.Results
Auto-antibodies against NMDA receptor or VGKC (LG1 or Caspr2) complex were not detected in sera of patients suffering from NS (n=6), NS plus other seizure types (n=16), primary generalized epilepsy (n=1) and community controls without epilepsy (n=7). Median Pyridoxal-phosphate levels in patients with NS compared to patients with primary generalized seizures and community controls were not significantly different. However, these median pyridoxal-phosphate levels are significantly lower compared to the range considered normal in Europeans.Conclusions
In this pilot study NS was not associated with serum anti-NMDA receptor or anti-VGKC complex antibodies and no association to pyridoxal-phosphate serum levels was found. 相似文献35.
目的:综合分析目前原发性高血压基因治疗的前景及其面临的主要问题。资料来源:应用计算机检索Pubmed数据库1996-01/2006-01有关原发性高血压基因治疗的文章,检索词“hypertension,genetherapy”,限定文章种类为“English”。同时检索万方数据2000-01/2006-01有关原发性高血压基因治疗的文章,检索词“原发性高血压,基因治疗/疗法”。资料选择:纳入标准:①关于原发性高血压基因治疗策略的研究。②关于基因治疗正义及反义基因的研究。③关于原发性高血压基因治疗载体的研究。排除标准:陈旧或重复性研究及综述。资料提炼:共收集到195篇与原发性高血压基因治疗相关的文献,其中30篇符合纳入标准。资料综合:①原发性高血压基因治疗目前有两种策略,即反义抑制策略和过度表达策略。反义抑制策略减少原发性高血压和心血管病理生理相关的基因转录和翻译;过度表达策略使血压降低相关基因的表达都增加,从而增加舒血管物质的生成使血管舒张。②原发性高血压基因治疗要选择高效转染分裂和非分裂细胞,易于大量制造,无免疫原性,无毒副作用,可载入大分子DNA,能整合进入宿主基因组,且不影响其他基因的载体。③目前面临着原发性高血压靶基因的界定、载体的选择等问题。结论:靶基因的界定,载体的构建和基因转移法是原发性高血压基因治疗的关键,基因治疗可减少传统药物治疗带来的副作用,降低原发性高血压的发病率,甚至治愈原发性高血压。 相似文献
36.
静息状态脑功能网络的研究及应用 总被引:1,自引:0,他引:1
目的:对静息状态网络的研究方法、初步的研究成果等作以介绍,并结合静息状态网络在阿尔茨海默病早期预警中的应用,介绍静息状态脑网络的应用。资料来源:应用计算机检索PubMed1980-01/2006-12与静息状态网络相关的文献,检索词“restingstate,functional connectivity”,并限定文献语言种类为“English”;同时计算机检索万方数据库1995-01/2006-12有关方面的文献,检索词为“静息,功能连接,阿尔茨海默病”,并限定语言种类为中文。资料选择:对资料进行初审,选取包括静息状态的相关文献,开始查找原文。纳入标准:①有关静息状态脑网络和功能连接的研究。②有关阿尔茨海默病的研究。排除标准:重复研究。资料提炼:共收集到53篇有关静息状态网络方面的研究,排除23篇重复性研究,30篇符合要求。资料综合:近年来,研究者发现大脑处于无任务的静息状态时,仍然存在着某种功能活动。这些现象表明大脑在静息状态时可能存在有组织的网络。这有助于对人脑高级意识和某些认知疾病的研究,因此,有关这方面的工作越来越受到人们的重视。结论:对静息状态网络的本质和规律的研究还很有限,对这个网络所支持的精确的功能还有待于进一步研究。 相似文献
37.
JY Nagata TF Rocha‐Lima BP Gomes CC Ferraz AA Zaia FJ Souza‐Filho A De Jesus‐Soares 《Australian dental journal》2015,60(3):416-420
Immature avulsed teeth are not usually treated with pulp revascularization because of the possibility of complications. However, this therapy has shown success in the treatment of immature teeth with periapical lesions. This report describes the case of an immature replanted tooth that was successfully treated by pulp revascularization. An 8‐year‐old boy suffered avulsion on his maxillary left lateral incisor. The tooth showed incomplete root development and was replanted after 30 minutes. After diagnosis, revascularization therapy was performed by irrigating the root canal and applying a calcium hydroxide paste and 2% chlorhexidine gel for 21 days. In the second session, the intracanal dressing was removed and a blood clot was stimulated up to the cervical third of the root canal. Mineral trioxide aggregate was placed as a cervical barrier at the entrance of the root canal and the crown was restored. During the follow‐up period, periapical repair, apical closure and calcification in the apical 4 mm of the root canal was observed. An avulsed immature tooth replanted after a brief extra‐alveolar period and maintained in a viable storage medium may be treated with revascularization. 相似文献
38.
39.
Balthasar L. Hug Daniel J. Witkowski Colin M. Sox Carol A. Keohane Diane L. Seger Catherine Yoon Michael E. Matheny David W. Bates 《Journal of general internal medicine》2010,25(1):31-38
CONTEXT
Medications represent a major cause of harm and are costly for hospitalized patients, but more is known about these issues in large academic hospitals than in smaller hospitals. 相似文献40.
JM Amici JY Bailly A Taieb 《Journal of the European Academy of Dermatology and Venereology》2010,24(3):308-316
Background Skin cancer surgery is usually performed on the face, and more specifically on and around the midfacial apertures. Each defect generated by the exeresis of a face tumor can be repaired by various advancement, rotation or transposition flaps techniques. Therefore the choice of the closure axis of a defect and its cicatricial and orificial consequences is decisive. Results The closure of a defect is usually made by symmetrically suturing its edges, across the incision axis according to the rule of halves. However, the closure axis of a defect is intentional and characterized by the subcutaneous suture axis which determines the induced tension orientation, and thus the possible displacement of the aperture free margins. The horizontal stretching principle guarantees the lack of impact on the 3 major apertures of the midfacial frame: eye, nostril and mouth. Conclusions This biomechanical concept is decisive to repair midfacial defect with functional and aesthetic results. It also provides objective arguments for the reparative techniques prioritization and the ability to codify those to be recommended as first‐line treatment in the surgical management of the face cutaneous tumours. 相似文献