瞬时性受体电位通道香草酸受体5、6与骨代谢的关系

目的:探讨瞬时性受体电位通道香草酸受体5、6与骨代谢的关系。资料来源:应用计算机检索PubMed数据库1999-01/2006-07相关瞬时性受体电位通道方面的文献,检索词“TRPV”,限定文献语言种类为English。资料选择:对资料进行初审,选取包括瞬时性受体电位通道香草酸受体5、6的文献,开始查找全文。纳入标准:对两者及瞬时性受体电位通道家族进行研究的文章。排除标准:研究内容局限于瞬时性受体电位通道香草酸受体1～4的文章。资料提炼:共检索到106篇关于瞬时性受体电位通道香草酸受体的文献,最终纳入30篇符合标准的文献。资料综合:瞬时性受体电位通道香草酸受体5、6是瞬时性受体电位通道超家族中的成员,是专门的上皮样钙离子通道。目前研究已经证明它们在肠道和肾脏等组织中有表达,并对跨细胞钙离子转运起着关键性调控作用。但在骨组织中表达情况相关报道较少,在骨代谢机制上的研究更少,本文针对目前两者与骨代谢的关系进行综述。结论:深入研究瞬时性受体电位通道香草酸受体5、6钙离子通道在骨代谢中的作用,对于那些与骨代谢相关疾病的治疗将能从分子水平上找到解决的方法。     

Blood transfusion costs: a multicenter study

The cost of delivering a unit of blood (whole blood or red cells) to a hospitalized patient was examined in 19 United States teaching hospitals. The average hospital acquisition cost was calculated by using the prices charged by regional blood centers for blood products. To this cost was added an estimate of costs incurred by hospitals for handling, testing, and administering blood. Across study sites, the average hospital cost per unit transfused was $155 and the average charge to the patient was $219. Acquisition cost, the price that hospitals pay for blood, was 37 percent of the total cost to the hospital; the other 63 percent of the hospital cost included costs for blood bank handling (13%), laboratory tests (43%), and blood administration (7%). Significant variations in blood transfusion cost were found within our sample. Most of the variability can be attributed to geographic location of the blood supply source, type of red cell product transfused, prices charged by blood transfusion services, and the frequency of laboratory tests. The results of this transfusion cost study may be helpful in determining the costs of health care delivery, especially when blood transfusions are indicated.     

Circulating malignant cells in non-Hodgkin's lymphoma: correlation with binding by peanut agglutinin

A significant number of patients with non-Hodgkin's lymphoma have peripheral blood involvement during the course of their disease. Because the expression of receptor for the lectin peanut agglutinin PNA by normal lymphocytes is associated with noncirculating (stationary phase) cells, we studied the relationship between PNA binding by lymphoma cells and the presence of clonal B cells in the blood of 38 patients with B-cell lymphoma. The binding of PNA by cells in tissues was determined by the immunoperoxidase method and by two-color flow cytometry. Circulating lymphoma cells (clonal B cells) were identified by a sensitive flow-cytometric technique (kappa-lambda analysis) and were also studied for PNA binding in some cases. In all, 16 of 38 (42%) of lymphomas were PNA+, including a spectrum of histologic types. Circulating lymphoma cells were demonstrated in 17 of 22 PNA-lymphomas, whereas only 3 of 16 of PNA+ lymphomas had such circulating cells. Thus, there is a significant association between PNA binding and peripheral blood involvement by lymphoma (P less than .005 by chi- square analysis). In 12 cases, the circulating and tissue lymphoma cells had similar expression of PNA receptor (2 PNA+ and 10 PNA- cases), indicating that modulation of the PNA binding sites did not occur. In three patients who presented with lymphosarcoma cell leukemia, the circulating malignant cells were PNA-. These findings suggest that for both normal and malignant lymphocytes the absence of binding sites for PNA is associated with the capacity of these cells to circulate freely.     

Partial purification and characterization of a growth factor for macrophage progenitor cells with high proliferative potential in mouse bone marrow

A population of macrophage progenitor cells, with high proliferative potential, has recently been demonstrated in postfluorouracil-treated and normal mouse bone marrow (BM) in vitro, when the newly discovered growth factor (synergistic activity, SA) is combined with a macrophage colony-stimulating factor (CSF) as a proliferative stimulus. SA, shown to be present in human spleen and placental conditioned media (HSCM and HPCM, respectively) have been studied and found to be unstable to trypsin digestion and to heating at 50 degrees C or above; stable between pH 4 and 9; nonadherent to Con-A-Sepharose; and to have an isoelectric point between pH 5 and 5.8 and a molecular weight of between 14,000 and 21,000 as indicated by gel filtration chromatography. SAs from both HSCM and HPCM have been purified 89- and 122-fold, respectively, by precipitation of extraneous proteins at pH 5 followed by chromatographing twice on Sephacryl S200. Neither of these partially purified SAs contain any CSF for mouse BM. These results indicate that the SAs from HSCM and HPCM may be closely related and that they are structurally different from CSFs derived from various murine sources that have been shown to be stable to proteolytic enzymes and heat.     

One-year mortality in patients with bone and soft tissue sarcomas as an indicator of delay in presentation

IntroductionFor many cancers, one-year mortality following diagnosis is a reflection of either advanced stage at diagnosis, multiple co-morbidities and/or complications of treatment. One-year mortality has not been reported for soft tissue or bone sarcomas. This study reports 1-year sarcoma mortality data over a 25-year period, investigates prognostic factors and considers whether a delay in presentation affects 1-year mortality.MethodsA total of 4,945 newly diagnosed bone sarcoma and soft tissue sarcoma patients were identified from a prospectively maintained, single institution oncology database. Of these, 595 (12%) died within 1 year of diagnosis. Both patient factors and tumour characteristics available at diagnosis were analysed for effect.ResultsThere was significant variation in one-year mortality between different histological subtypes. There has been no significant change in mortality rate during the last 25 years (mean: 11.7%, standard deviation: 2.8 percentage points). Soft tissue sarcoma patients who survived over one year reported a longer duration of symptoms preceding diagnosis than those who died (median: 26 vs 20 weeks, p<0.001). Prognostic factors identified in both bone and soft tissue sarcomas mirrored those for mid to long-term survival, with high tumour stage, large tumour size, metastases at diagnosis and increasing age having the greatest predictive effect.ConclusionsOne-year mortality in bone and soft tissue sarcoma patients is easy to measure, and could be a proxy for late presentation and therefore a potential performance indicator, similar to other cancers. It is possible to predict the risk of one-year mortality using factors available at diagnosis. Death within one year does not correlate with a long history but is associated with advanced disease at diagnosis.     

Characterization of megakaryocyte spleen colony-forming units by response to 5-fluorouracil and by unit gravity sedimentation

Properties of megakaryocyte progenitor cells in mouse bone marrow have been examined using an in vivo assay system. Perturbation with 5- fluorouracil (5-FU) and separation by unit gravity sedimentation was used to characterize the cells. Bone marrow was assayed for the presence of megakaryocyte colony-forming cells (MK CFU-S) by transplantation into lethally irradiated mice and examining spleen sections 10 days later. Donor mice were untreated or injected intravenously with 5-FU (150 mg/kg), 1 (FU-1) or 7 (FU-7) days beforehand. There was a lack of correlation between the numbers of MK CFU-S and cells giving rise to macroscopic spleen surface colonies (CFU- S10). The sedimentation profile of MK CFU-S in normal marrow was similar (modal velocity 4.16 +/- 0.05 mm/hr) to that of CFU-S10. In FU- 1 marrow, MK CFU-S exhibited a bimodal sedimentation profile, with peaks at 3.26 +/- 0.06 mm/hr and 4.53 +/- 0.07 mm/hr. The marrow content of CFU-S10 was reduced to 5% of normal, while MK CFU-S numbers were only reduced to 60%. In FU-7 marrow, the sedimentation profile of MK CFU-S (modal velocity 4.86 +/- 0.16 mm/hr) differed from that of CFU- S10 (5.5 +/- 0.16 mm/hr). It was concluded MK CFU-S and CFU-S10 are different entities. The MK colonies formed from FU-1 marrow contained on average 3.8-fold more cells than those formed from normal marrow. The enhanced megakaryocyte production may be accounted for on the basis of the generation-age model for cell proliferation. It is proposed that MK CFU-S are a heterogeneous population with regard to proliferation potential and that the FU-1 marrow contains cells that survive 5-FU and have a high proliferative potential. These cells may be equivalent among megakaryocytic progenitors to the high proliferative potential colony-forming cells of the granulocyte/macrophage series. They may be responsible for the enhanced megakaryocytopoiesis seen in the marrow of mice 7 days after the injection of 5-FU.