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121.
Isolation of myeloid progenitor cells from peripheral blood of chronic myelogenous leukemia patients 总被引:12,自引:0,他引:12
Myeloid progenitor cells (colony- and cluster-forming cells in semisolid medium, CFU-GM) were purified from the peripheral blood of chronic myelogenous leukemia (CML) patients. Lymphocytes, monocytes, and most immature myeloid cells were simultaneously depleted with specific monoclonal antibodies using an erythrocyte rosette technique for cell separation. Cells expressing Ia-like antigen were then selected from the residual cell population. Day 7 CFU-GM were enriched 44--116-fold in the IA+ cell fraction, when compared to the unseparated cells, and up to 47% of the cells could form a myeloid colony or cluster in culture. This cell fraction contained up to 92% undifferentiated blasts, with the remainder mostly promyelocytes. The enriched CFU-GM cells were dependent on an exogenous supply of colony- stimulating factor for growth, and colony formation was linear with cell concentration over a large range (10(4)-10(1) cells/ml). This technique of rosette depletion and enrichment with specific monoclonal antibodies provides a unique method for purifying a homogenous population of myeloid precursor cells with defined surface antigen characteristics. 相似文献
122.
Absence of an association between mannose-binding lectin polymorphism and rheumatoid arthritis 总被引:2,自引:0,他引:2
Stanworth SJ; Donn RP; Hassall A; Dawes P; Ollier W; Snowden N 《Rheumatology (Oxford, England)》1998,37(2):186-188
It has been proposed that mannose-binding lectin (MBL) interactions with
agalactosyl forms of IgG immunoglobulins found in rheumatoid synovial fluid
might lead to enhanced complement activation, an important mediator of the
joint damage in rheumatoid arthritis (RA). In order to investigate this
possible link between increased MBL-mediated activation of complement and
perpetuation of rheumatoid synovitis, we have compared the frequency of an
allelic form of MBL, known to be incapable of activating complement, in a
group of hospital patients with severe RA and control subjects. No evidence
was found to support an association between the presence of this MBL allele
and protection from rheumatoid disease; genotype frequencies were similar
in both groups. This suggests that complement activation via
MBL-agalactosyl IgG complexes is unlikely to play a major role in the
pathophysiology of RA.
相似文献
123.
Loss of bone mineral density in Chinese pre-menopausal women with systemic lupus erythematosus treated with corticosteroids 总被引:7,自引:1,他引:7
The adverse effect of disease and chronic corticosteroid therapy on bone
mineral density (BMD) in patients with systemic lupus erythematosus (SLE)
has been reported in several studies of Caucasian populations. As the
factors controlling bone homeostasis may be different in Asian populations,
we measured BMD in 52 pre-menopausal Chinese women (mean age 34.1 +/- 8.0
yr) with SLE (mean disease duration 6.4 +/- 4.5 yr) treated with prednisone
(mean daily dose 11.4 +/- 10.8 mg/day). Lumbar spine, hip (total and
subregions) and total body BMDs were measured in the SLE patients using
dual-energy X-ray absorptiometry (DEXA), and compared with those from
healthy controls matched for age, sex and body mass index. Compared to
controls, SLE patients were found to have lower BMD (g/cm2) at several
sites: the lumbar spine (0.98 vs 0.90, P = 0.001), Ward's triangle (0.72 vs
0.67, P = 0.03), total body (1.04 vs 1.01, P = 0.04) and total hip (0.87 vs
0.82, P = 0.05). There was no correlation between BMD at any region and
duration of disease, activity of disease or prednisone therapy (mean daily
dose, cumulative dose or treatment duration). When BMDs were compared
between controls and SLE patients, subgrouped according to those not on
calcium and those arbitrarily receiving calcium supplements (1 g/day),
significantly lower BMDs were found in those not on calcium compared to
both controls and SLE patients on calcium. BMDs in SLE patients on calcium
were not different from those in controls. The low prevalence of
osteoporosis in our SLE patients (4-6%) suggests significant loss of BMD in
Chinese SLE patients on corticosteroid therapy is less than that reported
in Caucasians (12-18%).
相似文献
124.
Do androgens enhance the response to antithymocyte globulin in patients with aplastic anemia? A prospective randomized trial 总被引:1,自引:0,他引:1
We analyzed the effect of antithymocyte globulin (ATG) with or without androgens in 121 patients with aplastic anemia. Fifty-three patients with moderate to severe aplastic anemia were prospectively randomized to receive ATG with or without oral androgens. Eleven of 26 patients (42%) receiving ATG plus androgen responded, including three complete and eight partial responses. Twelve of 27 patients (44%) receiving ATG plus placebo responded, including five complete and seven partial responses. The difference in response rates was not significant (P greater than .9). Survival was also comparable in the two groups; for patients with severe aplastic anemia, actuarial survival at two years was 55% +/- 24% (95% confidence interval) in patients receiving ATG plus androgen compared with 50% +/- 24% in the ATG plus placebo group (P = .65). Furthermore, results in both groups were indistinguishable from those obtained in 68 historical controls receiving ATG without androgens. These data indicate that androgens are not required in order to respond to antithymocyte globulin and the addition of androgens, as used in this trial, did not significantly improve response rates to ATG treatment. 相似文献
125.
Fabriek BO van Bruggen R Deng DM Ligtenberg AJ Nazmi K Schornagel K Vloet RP Dijkstra CD van den Berg TK 《Blood》2009,113(4):887-892
The plasma membrane glycoprotein receptor CD163 is a member of the scavenger receptor cystein-rich (SRCR) superfamily class B that is highly expressed on resident tissue macrophages in vivo. Previously, the molecule has been shown to act as a receptor for hemoglobin-haptoglobin complexes and to mediate cell-cell interactions between macrophages and developing erythroblasts in erythroblastic islands. Here, we provide evidence for a potential role for CD163 in host defense. In particular, we demonstrate that CD163 can function as a macrophage receptor for bacteria. CD163 was shown to bind both Gram-positive and -negative bacteria, and a previously identified cell-binding motif in the second scavenger domain of CD163 was sufficient to mediate this binding. Expression of CD163 in monocytic cells promoted bacteria-induced proinflammatory cytokine production. Finally, newly generated antagonistic antibodies against CD163 were able to potently inhibit cytokine production elicited by bacteria in freshly isolated human monocytes. These findings identify CD163 as a macrophage receptor for bacteria and suggest that, during bacterial infection, CD163 on resident tissue macrophages acts as an innate immune sensor and inducer of local inflammation. 相似文献
126.
Many studies have shown that psychophysiological parameters of processing emotional stimuli are associated with different personality traits in children, adolescents, and adults. Individuals with low autonomic baseline arousal, low orienting reaction, accelerated habituation, and reduced excitability particularly to punishing stimuli are characterised by a reduced experience of anxiety, decreased behaviour inhibition, and increased sensation seeking. These characteristics seem to raise the likelihood of dis-social behavior and are perceived as prognostically favourable for the development of antisocial personality disorders in childhood and adolescence. In contrast, an increased disposition towards anxiety, which is associated with increased autonomic reactivity, is recognised as a protective factor. Current data have shown that through special training, child and adolescent autonomic reactivity could be enhanced. Due to its versatility, this biological marker might be used for prevention in children at greater risk of developing antisocial behaviour. 相似文献
127.
128.
Pauly K Seiferth NY Kellermann T Backes V Vloet TD Shah NJ Schneider F Habel U Kircher TT 《Journal of the American Academy of Child and Adolescent Psychiatry》2008,47(11):1299-1310
ObjectiveSchizophrenia is among the most severe of psychiatric disorders, leading to impairments of affective and cognitive abilities. These dysfunctions affect each other mutually. Adolescent-onset schizophrenia (AOS) constitutes a particularly severe form of the disorder. In this study, possible dysfunctions of the neural correlates underlying the interaction of negative emotion and working memory in AOS were investigated.MethodDuring functional magnetic resonance imaging, 12 patients with AOS and 12 non-AOS adolescents performed a verbal n-back task. Intermittently, negative and neutral emotions were induced by olfactory stimulation. Group differences in working memory, emotion, and their interaction were evaluated.ResultsIn patients with AOS, lower performance sensitivity was observed, along with dorsolateral prefrontal, anterior cingulate, and inferior parietal hypoactivation during working memory demands. For negative versus neutral emotion induction, patients with AOS mainly showed increased brain activation compared with control subjects in widespread brain regions including the left orbitofrontal cortex and the medial frontal gyrus. Finally, during the interaction of emotion and cognition, altered patterns of activation in patients with AOS were found in the thalamocortical network, including the angular and the middle cingulate gyri extending to the precuneus. These activation differences were further decomposed by parameter estimates.ConclusionsOur results provide new insights into the neural correlates underlying the mutual influence of affective and cognitive symptoms in AOS. During the n-back task, areas typically associated with working memory performance were found hypoactivated in patients relative to the control subjects, including the dorsolateral prefrontal and parietal cortex and the anterior cingulate. However, patients with AOS mainly demonstrated increased activation in key areas of emotion processing, such as the left orbitofrontal cortex and medial frontal areas, during negative emotion induction. A dysfunctional thalamocortical network during the interaction mainly included regions involved in the integration of converging information—either on the subcortical (thalamus) or on a higher-order cortical level (comprising the angular gyrus). These findings point to dysfunctional emotion-cognition interactions in AOS, which may explain its poor prognosis. J. Am. Acad. Child Adolesc. Psychiatry, 2008;47(11): 1299–1310. 相似文献
129.
7抗凝剂——再灌注疗法的辅助疗法
更新的指南根据许多新的临床试验的结果,对4种新的抗凝剂提出了新的临床应用建议,见表2,有3项重要的临床试验:EXTRACT—TIMI25,OASIS-6以及CREATE证实,进行纤溶疗法的患者应用新的抗凝剂可以降低死亡率或MI的发生率。 相似文献
130.
Breij EC Heijnen P Vloet R Saito T van de Winkel JG Dijkstra CD Amor S Verbeek S 《Journal of neuropathology and experimental neurology》2005,64(4):304-311
Macrophages are considered essential mediators in multiple sclerosis (MS) pathogenesis, presumably through myelin phagocytosis and release of inflammatory mediators. Macrophages and microglia express activating Fcgamma receptors (FcgammaRI and FcgammaRIII), which depend on the FcRgamma chain for surface expression and signaling. In MS lesions, crosslinking of FcgammaR by immunoglobulins (IgG) directed against myelin may enhance myelin phagocytosis and inflammation. We studied the role of FcgammaR and anti-myelin antibodies in MOG35-55-induced experimental allergic encephalomyelitis (EAE) in C57BL/6 mice, a model of MS-like disease. Incidence and severity of EAE were similar in FcRy chain-/- (FcRgamma-/-) and wild-type (wt) mice, albeit with delayed onset in FcRgamma-/- mice. This demonstrates that the FcRy chain is not essential for induction of EAE, but that FcRgamma signaling may contribute to the preclinical phase. The role of FcgammaR in antibody-mediated demyelination was addressed by injection of anti-myelin antibodies (Z12 mAb) at onset of MOG35-55-induced EAE. Injection of Z12 mAb rapidly reduced survival time in both wt and FcRgamma-/- mice, demonstrating that antibody-mediated exacerbation of EAE is independent of the FcRgamma chain. Interestingly, Z12-induced exacerbation of inflammation and demyelination persisted longer in wt than FcRgamma-/- mice, suggesting that IgG-FcgammaR interactions may contribute to a sustained pathologic effect of anti-myelin antibodies in the CNS. 相似文献