Platelet transfusion for patients with cancer: clinical practice guidelines of the American Society of Clinical Oncology.

OBJECTIVE: To determine the most effective, evidence-based approach to the use of platelet transfusions in patients with cancer. OUTCOMES: Outcomes of interest included prevention of morbidity and mortality from hemorrhage, effects on survival, quality of life, toxicity reduction, and cost-effectiveness. EVIDENCE: A complete MedLine search was performed of the past 20 years of the medical literature. Keywords included platelet transfusion, alloimmunization, hemorrhage, threshold and thrombocytopenia. The search was broadened by articles from the bibliographies of selected articles. VALUES: Levels of evidence and guideline grades were rated by a standard process. More weight was given to studies that tested a hypothesis directly related to one of the primary outcomes in a randomized design. BENEFITS/HARMS/COST: The possible consequences of different approaches to the use of platelet transfusion were considered in evaluating a preference for one or another technique producing similar outcomes. Cost alone was not a determining factor. RECOMMENDATIONS: Appendix A summarizes the recommendations concerning the choice of particular platelet preparations, the use of prophylactic platelet transfusions, indications for transfusion in selected clinical situations, and the diagnosis, prevention, and management of refractoriness to platelet transfusion. VALIDATION: Five outside reviewers, the ASCO Health Services Research Committee, and the ASCO Board reviewed this document. SPONSOR: American Society of Clinical Oncology     

Quantification of PET studies with the very high-affinity dopamine D2/D3 receptor ligand [11C]FLB 457: re-evaluation of the validity of using a cerebellar reference region.

The very high-affinity position emission tomography (PET) radioligand [(11)C]FLB 457 was developed in order to study extrastriatal tissues, where the density of dopamine D(2)/D(3) receptors is one to two orders of magnitude lower than in the striatum. The present study investigated the validity of using the cerebellum as a reference region. Ten healthy volunteers underwent a 90-min dynamic PET study after the bolus injection of [(11)C]FLB 457. The total volume of distribution (VD(t)) was estimated for the thalamus, hippocampus, frontal cortex, and cerebellum using a two-tissue compartmental model with a metabolite-corrected arterial plasma input function. VD(t) was sensitive to co-injected stable FLB 457 in all regions, including the cerebellum. Ex vivo saturation studies were also conducted in 17 rats where the dose of stable ligand was varied over five orders of magnitude. Specific binding was estimated to account for more than half of the rat cerebellar uptake of [(11)C]FLB 457, questioning the latter as an estimate of nonspecific binding in human PET studies. To check whether the cerebellum is a reference region, the binding potential (BP) was calculated either from the VD(t) ratio or using the simplified reference tissue model (SRTM). A non-negligible density of D(2)/D(3) receptors in the cerebellum was shown to lead to underestimation of BP as well as erroneous estimation of differential occupancies. Binging potential estimates from the SRTM were found to be sensitive to changes in cerebral blood flow, providing further evidence for caution in the use of the cerebellum as a reference region in measures of [(11)C]FLB 457 binding.     

4个新2,2-二甲基色烯类化合物的分离和鉴定

从三叉苦(Evodia lepta Spr.Mer.)地上部分分离得到5个色烯类化合物,通过光谱解析和化学沟通的方法确定了它们的结构,其中4个为新化合物,依次命名为leptol B(I),ethyleptol B(I),methyleptol B(II)和leptene B(IV),另外1个为已知化合物 methylevodionol(V)。     

睫状神经营养因子在面神经再生中的表达变化及TGF-β、rhBMP-2的调控

目的　探讨睫状神经营养因子(CNTF)在面神经切断后的免疫定位及转化生长因子β(TGF-β)及人重组骨形成蛋白2(rhBMP-2)对其的调控作用。方法　选取面神经切断后不同时期的面神经核组织切片,通过免疫组化染色和图像分析对比不同时期面神经核中CNTF的浓度变化。结果　面神经切断后,术后1 d CNTF就开始表达并逐渐增加,分别于术后1周和1月面神经核运动元中CNTF的含量达到最大。此后逐渐下降。rhBMP-2对CNTF的表达无明显作用,而TGF-β能促进神经再生过程中CNTF的表达。结论　内源性CNTF在神经再生过程中对神经轴突的延伸也具有一定的促进作用。TGF-β可通过促进CNTF的表达而对面神经运动神经元起着重要的保护作用。     

Novel surveillance of Salmonella enterica serotype Heidelberg epidemics in a closed community

Pathogen and disease surveillance and control represent important public health priorities in high-density and high-risk populations such as nursing homes, cruise ships, military bases, hospitals, and prisons. Reportable disease investigations, along with syndromic surveillance, have been used to identify and characterize outbreaks in their early stages. In this study, we provide evidence that ongoing wastewater monitoring could be used to supplement these traditional methods in at-risk closed communities. During 2003-2005, a systematic and regularly timed human and farm-animal wastewater sampling scheme existed in several geographically distinct locations of a multisite population in Texas. In early July 2003, an outbreak of gastroenteritis caused by Salmonella enterica serotype Heidelberg occurred in the human population at one site. Wastewater samples from the weeks before, during, and after the outbreak were tested for the pathogen. Selective culture, serogrouping, and serotyping techniques as well as real-time polymerase chain reaction and pulsed field gel electrophoresis were used to detect and characterize the Salmonella Heidelberg in each sample. The ability to detect the causative pathogen of an outbreak while it circulates in the host populations prior to and after an outbreak, as well as during the outbreak peak, suggests that wastewater could be used as a supplemental disease surveillance tool. To further explore this possibility, two subsequent outbreaks of uncharacterized gastroenteritis in additional locations were also investigated using wastewater samples.     

Proteomic analysis to identify the role of LuxS/AI-2 mediated protein expression in Escherichia coli O157:H7

Microorganisms employ autoinducer molecules to modulate various bacterial processes including virulence expression, biofilm development, and bioluminescence. The universal autoinducer molecule AI-2 is hypothesized to mediate cell signaling in Escherichia coli O157:H7. We investigated the role of AI-2 on the E. coli O157:H7 cellular proteins using a two-dimensional (2D) gel electrophoresis-based proteomic approach. The protein expression patterns between two experimental comparisons were studied namely, 1) a wild type E. coli O157:H7 and its isogenic luxS mutant, and 2) the luxS mutant and the luxS mutant supplemented with AI-2 molecules. Eleven proteins were differentially expressed between the wild type and the luxS mutant strain, whereas 18 proteins were differentially expressed in the luxS mutant strain when supplemented with AI-2. The tryptophan repressor binding protein (WrbA), phosphoglycerate mutase (GpmA), and a putative protein YbbN were found to be differentially expressed under both experimental comparisons. The FliC protein which is involved in flagellar synthesis and motility was up-regulated in the wild type strain but was not influenced by the addition of synthetic AI-2 molecules to the luxS mutant suggesting the involvement of signaling molecules other than AI-2 on flagellar synthesis and motility.