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71.
Julie Seguier Véronique Gelsi-Boyer Mikael Ebbo Zeinab Hamidou Aude Charbonnier Emmanuelle Bernit Jean-Marc Durand Jean-Robert Harlé Norbert Vey Nicolas Schleinitz 《Autoimmunity reviews》2019,18(1):36-42
Background
We conducted a monocentric retrospective study of patients with myelodysplastic syndromes (MDS) and autoimmune or inflammatory disorders (AIMs) and a literature review. We analyzed the association with subgroups of the WHO 2016 MDS classification and patient's survival in a case control study. Risk factors associated with survival were analyzed by uni- and multivariate analysis.Results
From all MDS patients 11% presented with AIMs. These were heterogeneous and the most frequent where polyarthritis (25%) and autoimmune cytopenias (17%). No difference for frequency and type of AIMs was observed for the WHO 2016 MDS subgroups (p?=?.3). In the case control study WHO classification, karyotype abnormalities, IPSS-R and IPSS were similar in both groups. The overall survival from MDS diagnosis was better in the group with AIMs [10.3?±?0.6 (IC95% 6.2–12.9) versus 4.8?±?1.1?years (IC95% 4.2–8.7), p?=?.04]. The better survival was restricted to MDS with low or intermediate-1 IPSS [11.1?±?1.5 (IC95% 9.9-NR) versus 8.7?±?1.3?years (IC95% 4.8–10.3), p?=?.006]. The better survival was only observed when AIMs diagnosis was timely associated or appeared after MDS diagnosis (p?=?.04). Factors associated with a better overall survival and survival without AML were steroid dependence [respectively HR?=?0.042, p?=?.003, (IC95% 0.005–0.33) and HR?=?0.07, p?=?.002, (IC95% 0.013–0.39)], a diagnosis of AIMs and MDS timely associated [respectively HR?=?0.05, p?=?.009, (IC95% 0.006–0.478) and HR?=?0.1, p?=?.008, (IC95% 0.018–0.54)] or a diagnosis of AIMs after MDS [respectively HR?=?0.024, p?=?.009, (IC95% 0.001–0.39) and HR?=?0.04, p?=?.008, (IC95% 0.003–0.43)].Conclusion
Autoimmune and inflammatory diseases associated to MDS are heterogeneous. AIMs diagnosed after or concomitantly to MDS seems associated with a better survival. Prospective studies are necessary to demonstrate that autoimmunity is associated to a better control of the MDS clone. 相似文献72.
Mazarakis ND Azzouz M Rohll JB Ellard FM Wilkes FJ Olsen AL Carter EE Barber RD Baban DF Kingsman SM Kingsman AJ O'Malley K Mitrophanous KA 《Human molecular genetics》2001,10(19):2109-2121
In this report it is demonstrated for the first time that rabies-G envelope of the rabies virus is sufficient to confer retrograde axonal transport to a heterologous virus/vector. After delivery of rabies-G pseudotyped equine infectious anaemia virus (EIAV) based vectors encoding a marker gene to the rat striatum, neurons in regions distal from but projecting to the injection site, such as the dopaminergic neurons of the substantia nigra pars compacta, become transduced. This retrograde transport to appropriate distal neurons was also demonstrated after delivery to substantia nigra, hippocampus and spinal cord and did not occur when vesicular stomatitis virus glycoprotein (VSV-G) pseudotyped vectors were delivered to these sites. In addition, peripheral administration of rabies-G pseudotyped vectors to the rat gastrocnemius muscle leads to gene transfer in motoneurons of lumbar spinal cord. In contrast the same vector pseudotyped with VSV-G transduced muscle cells surrounding the injection site, but did not result in expression in any cells in the spinal cord. Long-term expression was observed after gene transfer in the nervous system and a minimal immune response which, together with the possibility of non-invasive administration, greatly extends the utility of lentiviral vectors for gene therapy of human neurological disease. 相似文献
73.
Cell division and deoxyribonucleic acid (DNA) synthesis in cultures of stimulated lymphocytes. 总被引:2,自引:2,他引:2 下载免费PDF全文
The responses of lymphocytes cultured with various stimulants were analysed with respect to DNA synthesis and cell division. Autoradiographic labelling with [3H]thymidine indicated that similar proportions of cells had incorporated this labelled precursor for DNA synthesis during both short and long periods of exposure to this specific precursor for DNA synthesis. Changes in labelling index (LI) after pulsing these cells with [3H]thymidine showed that exchange of labelled material, which could not be chased out with unlabelled thymidine, was responsible for the increases of LI seen. Failure to prevent this increase with excess unlabelled thymidine indicated that direct incorporation of [3H]thymidine did not account for this exchange. Using hydroxyurea and colcemid arrest to analyse cell cycle events in these cultures, it was shown that approximately 70 per cent of the responding cells in cultures of stimulated lymphocytes, while actively synthesizing DNA, were not in cell cycle for division. It was concluded that DNA turnover, involving synthesis and exchange of newly synthesized material, possibly DNA, was occurring in these cells. 相似文献
74.
75.
76.
Throckmorton AL Allaire PE Gutgesell HP Matherne GP Olsen DB Wood HG Allaire JH Patel SM 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2002,48(3):216-221
Ventricular assist devices (VADs) are a valid option for long term circulatory support in pediatric patients with postoperative myocardial failure or debilitating heart defects. Most clinical experience to date has involved the short-term support of patients weighing 6 kg and larger. For cases of VAD implementation in pediatric patients, the assist device showed tremendous promise in reversing cardiac failure and providing adequate support as a bridge to cardiac transplantation. The Medos-HIA system, Berlin Heart, Medtronic Bio-Medicus Pump, Abiomed BVS 5000, Toyobo-Zeon pumps, and Hemopumps have proven successful for short-term circulatory support for the pediatric population. The Jarvik 2000 and Pierce-Donachy pediatric system further demonstrate the potential to be used for pediatric circulatory support. The clinical and experimental success of these support systems provide encouragement to believe that long-term support is possible. 相似文献
77.
S. Aabo J. P. Christensen M. S. Chadfield B. Carstensen J. E. Olsen M. Bisgaard 《Avian pathology》2002,31(1):41-47
The aim of the present study was to compare the invasion of selected zoonotic Salmonella serotypes of poultry in an in vivo chicken intestinal loop model and also in vitro in epithelial cell cultures. Invasion was measured relative to a reference strain, Salmonella Typhimurium 4/74 inv H201::Tn phoA . Two serotypes demonstrated intracellular log 10 counts that differed significantly from all other serotypes tested: Salmonella Enteritidis PT4 being 1.5 log 10 colony forming units (CFU) (31-fold) higher, and Salmonella Tennessee being 0.7 log 10 CFU (fivefold) lower than the reference strain ( P h 0.0001). A group of serotypes, which can be vertically transmitted, showed significantly higher intracellular counts (fourfold to eightfold) than the reference strain. The group included S. Typhimurium 4/74, S. Typhimurium DT104 (poultry and porcine isolates), S. Enteritidis PT1, S. Enteritidis PT6, S. Enteritidis PT8, and Salmonella Berta. The serotypes Salmonella Hadar, Salmonella Virchow, S. 4,12:b:-, S. Typhimurium DT41, and Salmonella Infantis, most of which are considered horizontally transmitted, did not show significantly different intracellular counts from the reference strain. Results from the cell culture invasion studies agreed with the in vivo data, with the exception of S. Berta and the poultry isolate of S. Typhimurium DT104. 相似文献
78.
Curtas AR Wood HG Allaire PE McDaniel JC Day SW Olsen DB 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2002,48(5):552-561
To finalize the design of the next generation of the HeartQuest left ventricular assist device, a suitable impeller had to be designed and tested. The new prototype was based on calculations and test results of previous designs, but required several changes to decrease the size. For most pump designs, this is a simple matter of altering impeller geometry and rotational speed to achieve the desired pressure rise and flow rate. However, this particular pump was limited by housing geometry and the magnetic bearings that support the impeller. Without much freedom in the overall impeller size, the only parameters open to the designers were the blade profiles and the rotating speed. Rather than build several candidates and test them in a rig at enormous cost, computational models of several designs were tested and analyzed. This not only saved money, but also sped up the development time for the project. The computer models were developed in TASCflow, a computational fluid dynamics software package from AEA Technologies. This paper analyzes the data from several of the selected models, paying close attention to pumping performance and general trends from specific design changes. 相似文献
79.
An IFN-beta-albumin fusion protein that displays improved pharmacokinetic and pharmacodynamic properties in nonhuman primates. 总被引:6,自引:0,他引:6
Cynthia Sung Bernardetta Nardelli David W LaFleur Erich Blatter Marta Corcoran Henrik S Olsen Charles E Birse Oxana K Pickeral Junli Zhang Devanshi Shah Gordon Moody Solange Gentz Lisa Beebe Paul A Moore 《Journal of interferon & cytokine research》2003,23(1):25-36
The long half-life and stability of human serum albumin (HSA) make it an attractive candidate for fusion to short-lived therapeutic proteins. Albuferon (Human Genome Sciences [HGS], Inc., Rockville, MD) beta is a novel recombinant protein derived from a gene fusion of interferon-beta (IFN-beta ) and HSA. In vitro, Albuferon beta displays antiviral and antiproliferative activities and triggers the IFN-stimulated response element (ISRE) signal transduction pathway. Array analysis of 5694 independent genes in Daudi-treated cells revealed that Albuferon beta and IFN-beta induce the expression of an identical set of 30 genes, including 9 previously not identified. In rhesus monkeys administered a dose of 50 microg/kg intravenously (i.v.) or subcutaneously (s.c.) or 300 microg/kg s.c., Albuferon beta demonstrated favorable pharmacokinetic properties. Subcutaneous bioavailability was 87%, plasma clearance at 4.7-5.7 ml/h/kg was approximately 140-fold lower than that of IFN-beta, and the terminal half-life was 36-40 h compared with 8 h for IFN-beta. Importantly, Albuferon beta induced sustained increases in serum neopterin levels and 2',5' mRNA expression. At a molar dose equivalent to one-half the dose of IFN-beta, Albuferon beta elicited comparable neopterin responses and significantly higher 2',5'-OAS mRNA levels in rhesus monkeys. The enhanced in vivo pharmacologic properties of IFN-beta when fused to serum albumin suggest a clinical opportunity for improved IFN-beta therapy. 相似文献
80.
Reproducibility of histomorphologic diagnoses with special reference to the kappa statistic 总被引:14,自引:0,他引:14
H Svanholm H Starklint H J Gundersen J Fabricius H Barlebo S Olsen 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》1989,97(8):689-698
Systems for classification and grading used in pathology should ideally be biologically meaningful and at least be reproducible from one pathologist to another. A statistical method to evaluate reproducibility (non-chance agreement) for several observers using nominal or ordinal categories has been developed and refined over the past few decades--the kappa statistic. A high level of observed agreement among different pathologists can either signify a high level of reproducibility, if agreement by chance is low, or express a low level of reproducibility, if agreement by chance is almost as high as the observed agreement. Therefore, the observed agreement says nothing in itself, unless it is low. The kappa value, however, indicates how much better the observers are compared to a throw of the dice, and therefore gives the real credit to the agreement which was found. We have developed a user-friendly computer program for calculating inter- and intra-observer agreement of 2 or more observers. By calculating associations between different categories and different observers, the statistic furthermore obtains a function close to the parameter of accuracy. We recommend the use of the above method before a set of nominal or rank scale parameters are used for deciding prognosis and treatment of patients. By submitting a diskette the computer program will be available at no cost. 相似文献