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81.
Originally, allogeneic hematopoietic stem cell transplantation (HSCT) was viewed as a form of rescue from the marrow lethal
effects of high doses of chemo-radiotherapy used to both eradicate malignancy and to provide sufficient immunosuppression
to ensure allogeneic engraftment. Clear evience of a therapeutic graft-versus-tumor (GVT) effect mediated by allogeneic affector
cells (T cells) has prompted the exploration of HSCT regimens that rely solely upon host immunosuppression (non-myeloblative)
to facilitate allogenic donor engraftment. The engrafted donor effector cells are then used to accomplish the task of eradicating
host malignant cells. The non-myeloblative regimen developed in Seattle uses 2 Gy total body irradiation (TBI) before transplant
followed by postgrafting cyclosporine (CSP) and mycophenolate mofetil (MMF). This regimen resulted in initial mixed donor-host
chimerism in all patients with hematologic malignancies and genetic disorders who received HLA-matched sibling allografts.
The 17% incidence of graft rejection was reduced to 3% with the addition of fludarabine, 30 mg/m2/day on d-4,-3, and-2. The non-myeloblative combination of fludarabine/TBI has also been successful at achieving high engraftment
rates in recipients of 10 of 10 HLA antigen matched unrelated donor HSCTs in patients with hematologic malignancies. By reducing
acute toxicities relative to conventional HSCT, most patients have received their pre- and post-HSCT therapy almost exclusively
as outpatients. Acute and chronic GVHD occur after non-myeloablative HSCT, but the incidence and severity appear less compared
to conventional HSCT. As in conventional transplants, immune dysregulation from GVHD and its treatment and delayed reconstitution
of immune function continue to present risks to patients who have otherwise undergone successful non-myeloablative HSCT. Cellular
therapeutic effects have been nobserved after non-myeloblative HSCT such as correction of inherited genetic disorders, and
eradication of hematologic malignant diseases and renal cell carcinoma via GVT responses. 相似文献
82.
Applications of a rat multiple tissue gene expression data set 总被引:4,自引:0,他引:4
Walker JR Su AI Self DW Hogenesch JB Lapp H Maier R Hoyer D Bilbe G 《Genome research》2004,14(4):742-749
With the sequencing and assembly of the rat genome comes the difficult task of assigning functions to genes. Tissue localization of gene expression gives some information about the potential role of a gene in physiology. Various examples of the utility of multiple tissue gene expression data sets are illustrated here. First, we highlight their use in finding genes that might play an important role in a particular tissue on the basis of exclusive expression in that tissue or coexpression with a gene or genes with known function. Second, we show how this data might be used to explain known phenotypic differences between strains. Third, we show how expression patterns of genes in a genomic interval might identify candidate genes in quantitative trait loci (QTL) mapping studies. Lastly, we show how multiple tissue and species data can help researchers prioritize follow up studies to microarray experiments. All of these applications of multiple tissue gene expression data sets will play a role in functionally annotating the rat genome. 相似文献
83.
For resolution of the controversial taxonomic status of Babesia microti in relation to other Babesia and Theileria spp. a phylogenetic analysis of an American and a German B. microti strain was performed on the basis of sequences of the small-subunit rRNA gene (rDNA) using distance-matrix, maximum-parsimony,
and maximum-likelihood algorithms. Both B. microti isolates clearly separated from a group containing other Babesia spp. as well as from a second group consisting of Theileria spp. Interestingly, the B. microti isolates clustered in a monophyletic group together with other piroplasm species of unclear taxonomic status, B. rodhaini, and a recently described small canine piroplasm species. These results support the existence of a third taxonomic entity
of equal rank besides the Babesiidae and Theileriidae.
Received: 11 February 2000 / Accepted: 24 February 2000 相似文献
84.
Rainer Gothe 《Parasitology research》1967,29(2):149-158
Zusammenfassung 1. Aegyptianella pullorum nimmt im allgemeinen in Hühnern, unabhängig vom Infektionsweg, einen typischen Verlauf. Die Entwicklung des Parasiten vollzieht sich in den Erythrozyten des Wirtstieres in drei Phasen, die aber nur auf Grund typischer morphologischer Merkmale unterscheidbar sind und sich in der zeitlichen Reihenfolge nicht trennen lassen.2. Durch die Übertragung des Blutes von Kücken, die durch Zeckenbisse infiziert wurden, auf empfängliche Tiere in bestimmten Zeitabständen nach dem Saugakt infektiöser Argas (Persicargas) persicus-Zecken sowie auf Grund histologischer Untersuchungen infizierter Kücken kann eine präerythrozytäre Phase in der Entwicklung von Aegyptianella pullorum ausgeschlossen werden.3. Die in weißen Blutzellen, den Kupfferschen Sternzellen der Leber und frei im Blutplasma gefundenen Parasiten werden nicht als exoerythrozytäre Entwicklungsstadien von Aegyptianella pullorum interpretiert.
Investigations into the development and the course of infection of aegyptianella pullorum Carpano, 1928, in chicken
Summary Generally Aegyptianella pullorum takes a typical course in chicken independent from the route of infection. In the erythrocytes of vertebrate hosts, the development of the parasite passes through three phases, which can be differentiated only by the typical morphological features.By transmission of blood from naturally infected chicken to susceptible animals, after engorgement of infected Argas (Persicargas) persicus, as well as by histological investigations of infected chicken, a preerythrocytical phase in the development of Aegyptianella pullorum can be excluded.The parasites, found in white blood cells, in the Kupffer cells of the liver and free in the blood plasma, are not interpreted as exoerythrocytic developmental stages of Aegyptianella pullorum.相似文献
85.
Utility of Major Leukocyte Subpopulations for Monitoring Secondary Cytomegalovirus Infections in Renal-Allograft Recipients by PCR 总被引:2,自引:1,他引:2
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Peter Schfer Werner Tenschert Liana Cremaschi Kai Gutensohn Rainer Laufs 《Journal of clinical microbiology》1998,36(4):1008-1014
The feasibility of the major peripheral blood leukocyte (PBL) subsets for use in qualitative and quantitative PCR to monitor secondary cytomegalovirus (CMV) infection and ganciclovir therapy was assessed with 188 blood samples derived from 40 CMV immunoglobulin G-positive renal-allograft recipients. In pp65 antigen-positive patients all leukocyte fractions, but only 79.5% of plasma preparations, were PCR positive. In pp65 antigen-negative samples from patients after antiviral treatment only 7.3% of polymorphonuclear cell (PMNL) samples, but 81.8% of peripheral blood mononuclear cells (PBMC), and 10.9% of plasma samples remained PCR positive. Similarly, in patients with latent infections only 5.0% of PMNL, but 51.7% of PBMC preparations, and 8.0% of plasma samples were PCR positive. Regarding patients with active CMV infection, CMV DNA copy numbers in PMNL correlated significantly with pp65 antigen-positive cell counts before and after onset of ganciclovir therapy. Significant differences in CMV DNA copy numbers in PMNL and plasma were observed (i) between patients with symptomatic infection and those with asymptomatic infection and (ii) between patients with active infection and those with latent infection. In contrast, PBMC harbored equally low CMV DNA levels both in patients with active infection and those with latent infections, and no decline of CMV DNA load in PBMC was observed during antiviral treatment. We conclude that detection of CMV DNA in PMNL, not in PBMC, is associated with active infections and is more sensitive than detection of CMV DNA in plasma. Negative PCR results for PMNL after antiviral therapy indicate recovery, and fewer unwanted positive results occur compared to PBMC and plasma. Therefore, purified PMNL should be preferred for analysis by qualitative CMV PCR to avoid unwanted positive results. The CMV DNA load in PBMC compared with that in PMNL is negligible during active infection, so mixed PBL are sufficient for use in quantitative PCR. 相似文献
86.
Task-specific neural activity in the primate prefrontal cortex 总被引:12,自引:0,他引:12
Real-world behavior is typically more complicated than a one-to-one mapping between a stimulus and response; the same stimulus can lead to different behaviors depending on the situation, or the same behavior may be cued by different stimuli. In such cases, knowledge of the formal demands of the task at hand is required. We found that in monkeys trained to alternate between three tasks, the activity of many neurons in the prefrontal cortex was task dependent. This included changes in overall firing rate, in firing-rate profiles (shape of responses over time), and in stimulus and response selectivity. These findings support the hypothesis that a major prefrontal function is the acquisition and implementation of task context and the "rules" used to guide behavior. 相似文献
87.
Beate M Herbert Olga Pollatos Rainer Schandry 《International journal of psychophysiology》2007,65(3):214-227
Theories of emotion consider the self-perception of visceral activity to play an important role in emotion. This study examined the relationship between interoceptive sensitivity and both the subjective emotional experience and the processing of emotional pictures. According to their results in a heartbeat detection task subjects were classified as good (N = 17) or poor (N = 20) heartbeat perceivers. Event-related potentials were recorded while subjects viewed pleasant, neutral and unpleasant pictures and SAM ratings were examined. Good heartbeat perceivers showed significantly greater P300 and slow wave amplitudes for emotional pictures at antero-inferior, medial and posterior electrode sites and experienced a greater arousal for emotional pictures compared to poor heartbeat perceivers. The heartbeat perception score correlated significantly positive both with emotional P300 and slow wave amplitudes as well as with the arousal ratings for emotional pictures. The results indicate that there is a significant and strong association between interoceptive sensitivity and the intensity of emotional experience as well as the central processing of emotional stimuli. 相似文献
88.
The first and second internal transcribed spacers (ITS1, ITS2) as well as the intervening 5.8S coding region of the rRNA
gene were characterized in eight Babesia canis isolates of differing geographic origin, vector specificity, and pathogenicity to dogs. The genotypes determined by sequencing
segregated into three clearly separated groups close to or near the species level and correspond to the previously proposed
subspecies B. canis canis, B. canis vogeli, and B. canis rossi. The three genotypes can be distinguished by Sau96I digestion of the polymerase chain reaction (PCR)-amplified rDNA target.
Received: 12 December 1997 / Accepted: 5 January 1998 相似文献
89.
Functionally active complement proteins C6 and C7 detected in C6- and C7-deficient individuals 总被引:4,自引:2,他引:4
R. WÜRZNER A. ORREN P. POTTER B. P. MORGAN D. PONARD P. SPTH M. BRAI M. SCHULZE L. HAPPE O. G
TZE 《Clinical and experimental immunology》1991,83(3):430-437
Two sensitive sandwich ELISAs based on monoclonal antibodies directed to native C6 and C7 allowed the detection and quantitation of these complement proteins in 20 out of 37 serum samples from individuals who had previously been classified as deficient in these proteins as assessed by immunochemical and/or functional assays. Furthermore, serum from four C6-deficient and one combined C6-/C7-deficient individual showed an increase in the terminal complement complex (TCC) and a decrease in native C6 and C7 after complement activation as assayed by specific ELISAs. Despite their (incomplete) deficiencies, these individuals therefore possess functionally active terminal complement proteins with respect to their ability to generate the TCC. As these individuals have no history of a susceptibility to neisserial infections, even low concentrations of functionally active C6 and C7 may provide sufficient protection against those micro-organisms whose destruction requires TCC formation. 相似文献
90.
Autoimmunity and inflammation due to a gain-of-function mutation in phospholipase C gamma 2 that specifically increases external Ca2+ entry 总被引:3,自引:0,他引:3
Yu P Constien R Dear N Katan M Hanke P Bunney TD Kunder S Quintanilla-Martinez L Huffstadt U Schröder A Jones NP Peters T Fuchs H de Angelis MH Nehls M Grosse J Wabnitz P Meyer TP Yasuda K Schiemann M Schneider-Fresenius C Jagla W Russ A Popp A Josephs M Marquardt A Laufs J Schmittwolf C Wagner H Pfeffer K Mudde GC 《Immunity》2005,22(4):451-465
The identification of specific genetic loci that contribute to inflammatory and autoimmune diseases has proved difficult due to the contribution of multiple interacting genes, the inherent genetic heterogeneity present in human populations, and a lack of new mouse mutants. By using N-ethyl-N-nitrosourea (ENU) mutagenesis to discover new immune regulators, we identified a point mutation in the murine phospholipase Cg2 (Plcg2) gene that leads to severe spontaneous inflammation and autoimmunity. The disease is composed of an autoimmune component mediated by autoantibody immune complexes and B and T cell independent inflammation. The underlying mechanism is a gain-of-function mutation in Plcg2, which leads to hyperreactive external calcium entry in B cells and expansion of innate inflammatory cells. This mutant identifies Plcg2 as a key regulator in an autoimmune and inflammatory disease mediated by B cells and non-B, non-T haematopoietic cells and emphasizes that by distinct genetic modulation, a single point mutation can lead to a complex immunological phenotype. 相似文献