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51.
Histamine levels in stored platelet concentrates. Relationship to white cell content 总被引:1,自引:0,他引:1
The histamine levels in samples from platelet concentrates (PC) were measured at various storage times by a radioenzymatic assay. Elevated histamine levels were detected in 5 of 14 PC after 3 days of storage (range, less than 1 to 13.3 ng/ml) and in 9 of 14 PC after 5 days (range, less than 1 to 22.2 ng/ml). A very good linear correlation (r = 0.913) was found between the initial white cell content of the PC and the histamine level at 5 days of storage. The rise in histamine content was not influenced by the type of plastic container. The results indicate a process of histamine release by the white cells during storage. Although histamine is metabolized rapidly in vivo, a critical histamine threshold could be reached in man by the rapid infusion of stored PC containing high levels of histamine. This could explain some unexpected transfusion reactions in patients receiving PC. 相似文献
52.
Walker AS; Peto TE; Babiker AG; Darbyshire JH 《QJM : monthly journal of the Association of Physicians》1998,91(6):423-438
The Concorde trial compared immediate (Imm) with deferred (Def) AZT
monotherapy in asymptomatic HIV-positive participants. Haematological and
immunological markers and weight were measured throughout, and correlated
with clinical endpoints. Markers associated with disease progression (CD4
lymphocyte count and percentage, platelets, p24 antigen and beta 2
microglobulin favoured Imm: those associated with toxicity (haemoglobin,
neutrophils and white cell count) favoured Def. CD8 and total lymphocyte
count did not differ significantly between groups. In multivariate
analysis, the combination of baseline CD4, p24 antigen and beta 2m was the
best baseline predictor of disease. Including change in CD4 and beta 2m at
12 weeks, or changes over follow- up in these markers significantly
improved the fit. Markers were also incorporated into the definition of
'clinical' endpoints. Hazard ratio estimates from end-points that included
CD4 < 50 and CD4 < 25 were closest to those for AIDS or death alone,
but added very few extra events. Use of other landmark CD4 counts (100 or
greater) or relative decreases in counts (25% or more) increased the number
of events, but overestimated the effect of immediate AZT. Although AZT had
a beneficial effect on the surrogate markers of efficacy evaluated, these
changes did not predict clinical outcome, nor could the markers be usefully
incorporated into an endpoint definition.
相似文献
53.
Angela AG van Tilborg Chris H Bangma Ellen C Zwarthoff 《International journal of urology》2009,16(1):23-30
Early detection of bladder cancer and its recurrences is essential for improved prognosis and long-term survival. The detection and follow-up of these patients is currently based on cystoscopy, which is expensive and invasive, and, in most cases, cytology, which is non-invasive but not very sensitive. During recent years, many urine-based tests have been developed and tested in different patient populations. In this review we discuss new developments for biomarkers in bladder cancer that have potential use in surveillance and screening. In almost all publications authors compare sensitivity of the test with a concomitantly executed cystoscopy, for example, determine cross-sectional sensitivity. However, it has also been shown that false positive test results may be followed by a positive cystoscopy in the near future, showing that cystoscopy itself does not provide 100% sensitivity. This suggests that for a proper evaluation of urine-based tests, longitudinal studies should be carried out and the results communicated to the urologist. 相似文献
54.
Brief treatment with the glucocorticoid receptor antagonist mifepristone normalizes the reduction in neurogenesis after chronic stress 总被引:3,自引:0,他引:3
Oomen CA Mayer JL de Kloet ER Joëls M Lucassen PJ 《The European journal of neuroscience》2007,26(12):3395-3401
In rodents, stress suppresses adult neurogenesis. This is thought to involve activation of glucocorticoid receptors in the brain. In the present study, we therefore questioned whether glucocorticoid receptor blockade by mifepristone can normalize the effects of chronic stress on adult neurogenesis. Rats received mifepristone on the last 4 days of a 21-day chronic unpredictable and inescapable stress regimen. Neurogenesis was analysed by stereological quantification of adult-generated cell survival (bromodeoxyuridine), young neuronal survival (doublecortin) and cell proliferation (Ki-67). The results show that only 4 days of mifepristone treatment normalized the stress-induced reductions in neurogenesis. Importantly, mifepristone by itself had no effect on neurogenesis. We conclude that, contrary to other compounds interfering with the effects of chronic stress on neurogenesis, like antidepressants, the normalizing effects of mifepristone on neurogenesis are rapid and particularly potent in a high stress environment. This neurogenic action of mifepristone could potentially contribute to its clinical mechanism of action. 相似文献
55.
AG Stewart 《British journal of pharmacology》2009,158(4):933-935
The active resolution of inflammation is recognized as offering new opportunities to generate novel anti-inflammatory agents. The emerging appreciation of the importance of active resolution in regulation of inflammation also creates an imperative to examine developing and existing agents for their potential to influence these pathways. This themed issue of the British Journal of Pharmacology contains papers that discuss the roles of annexin-1, lipoxins and related lipid products of fish oils as well as other mechanisms involved in active resolution and their receptor targets.This article is part of a themed issue on Mediators and Receptors in the Resolution of Inflammation. To view this issue visit http://www3.interscience.wiley.com/journal/121548564/issueyear?year=2009 相似文献
56.
Background and purpose:
In the mammalian brain, histaminergic neurotransmission is mediated by the postsynaptic histamine H1 and H2 receptors and the presynaptic H3 autoreceptor, which also acts as a heteroreceptor. The H1 receptor has been implicated in spatial learning and memory formation. However, pharmacological and lesion studies have revealed conflicting results. To examine the involvement of histamine H1 receptor in spatial reference and working memory formation, H1 receptor knockout mice (KO) were tested in the eight-arm radial maze. Previously, we found that the H1 receptor-KO mice showed reduced emotionality when confronted with spatial novelty. As it is known that emotions can have an impact on spatial learning and memory performance, we also evaluated H1 receptor-KO mice in terms of emotional behaviour in the light–dark box.Experimental approach:
Mice lacking the H1 receptor and wild-type mice (WT) were tested for spatial reference and working memory in an eight-arm radial maze with three arms baited and one trial per day. Emotional behaviour was measured using the light–dark test.Key results:
The H1 receptor-KO mice showed impaired spatial reference and working memory in the radial maze task. No significant differences between H1 receptor-KO and WT mice were observed in the light–dark test.Conclusions and implications:
The spatial memory deficits of the H1 receptor-KO mice might be due to the reported changes in cholinergic neurochemical parameters in the frontal cortex and the CA1 subregion of the hippocampus, to impaired synaptic plasticity in the hippocampus, and/or to a dysfunctional brain reward/reinforcement system. 相似文献57.
Patty H Spruit Sabine Siesling Marloes AG Elferink Ernest JA Vonk Carel JM Hoekstra 《Radiation oncology (London, England)》2007,2(1):1-6
Background
To correlate the metabolic changes with size changes for tumor response by concomitant PET-CT evaluation of lung cancers after radiotherapy.Methods
36 patients were studied pre- and post-radiotherapy with18FDG PET-CT scans at a median interval of 71 days. All of the patients were followed clinically and radiographically after a mean period of 342 days for assessment of local control or failure rates. Change in size (sum of maximum orthogonal diameters) was correlated with that of maximum standard uptake value (SUV) of the primary lung cancer before and after conventional radiotherapy.Results
There was a significant reduction in both SUV and size of the primary cancer after radiotherapy (p < 0.00005). Among the 20 surviving patients, the sensitivity, specificity, and accuracy using PET (SUV) were 94%, 50%, 90% respectively and the corresponding values using and CT (size criteria) were 67%, 50%, and 65% respectively. The metabolic change (SUV) was highly correlated with the change in size by a quadratic function. In addition, the mean percentage metabolic change was significantly larger than that of size change (62.3 ± 32.7% vs 47.1 ± 26.1% respectively, p = 0.03)Conclusion
Correlating and incorporating metabolic change by PET into size change by concomitant CT is more sensitive in assessing therapeutic response than CT alone. 相似文献58.
Mager SR Oomen MH Morente MM Ratcliffe C Knox K Kerr DJ Pezzella F Riegman PH 《European journal of cancer (Oxford, England : 1990)》2007,43(5):828-834
Studies using fresh-frozen tissue samples originating from different centres, as is often the case in EORTC related translational research, can show conflicting research results due to heterogeneity in the quality of samples and associated data from each centre. The development of infrastructure for the European Human Frozen Tumour Tissue Bank (TuBaFrost) anticipated this problem and Standard Operating Procedures (SOPs) have been developed to ensure samples collected are of consistent high quality and variation in research results is minimised. The SOPs drew on the best practice standard workflows and operating procedures employed by members of the TuBaFrost Consortium and key tissue bank initiatives worldwide. It was essential to provide workable solutions that reflect the variety in infrastructure and resources at the potential collecting centres and also the fact that it is not necessary to standardise every step of the collection and storage process in order to collect high quality tissue. Hence, the TuBaFrost SOPs detail the compulsory measures that must be implemented in order to become a TuBaFrost collecting centre and also make advisory recommendations regarding the less critical factors. Accordingly, the TuBaFrost SOPs are very flexible and to illustrate this the complete SOP for collecting, freezing and storing tissue at the Erasmus MC Tissue Bank is included. These TuBaFrost SOPs could equally be applicable to centres collecting samples for EORTC related translational research studies in order to standardise sample quality and produce reliable and reproducible research results. 相似文献
59.
60.
Paulo CJL Santos Renata AG Soares Diogo BG Santos Raimundo M Nascimento George LLM Coelho José C Nicolau José G Mill José E Krieger Alexandre C Pereira 《BMC medical genetics》2011,12(1):13