人骨髓间充质干细胞分离培养及血管内皮生长因子对其产生的诱导分化作用

目的：目前有关骨髓间充质干细胞向内皮细胞诱导分化的研究较少。本实验分离和培养人骨髓间充质干细胞，用带有VEGF165的质粒转染人骨髓间充质干细胞，探讨血管内皮生长因子对其体外诱导分化的作用。 方法：实验于2005—04／2006—04在吉林大学人兽共患病教育部重点实验室完成。取成人的已排除血液系统肿瘤疾病的新鲜骨髓（自愿提供），采用Percoll梯度分离培养骨髓间充质干细胞，于倒置显微镜下观察细胞形态变化和生长情况。原代细胞培养至增殖接近融合状态时，单克隆培养法分离传代培养，扩增骨髓间充质干细胞。采用流式细胞术检测细胞免疫学表型。在原核细胞大肠杆菌DH5α中复制扩增和提取，纯化、克隆pcDNA3．0-VEGF165质粒。用脂质体转染法转染骨髓间充质干细胞：应用流式细胞术检测诱导后骨髓间充质干细胞免疫学表型变化j并采用免疫荧光染色鉴定转染情况，并设质粒空载和未转染的骨髓间充质干细胞为对照。 结果：人骨髓间充质干细胞原代培养1周后，造血细胞消失，贴壁细胞体积增大，呈现梭形外观，有粗大的细胞突起伸出。2周后细胞融合成单层，梭形突起变长，排列有明显的方向性，细胞排列成旋涡状、网状、辐射状。流式细胞术显示，人骨髓间充质干细胞免疫学表型CD44、CD29阳性，CD34、CD31、CD45阴性。VEGF165诱导骨髓间充质千细胞后CD44表达明显降低，CD31明显升高。免疫荧光染色显示，用FITC标记后的VEGF抗体使细胞显现绿色荧光，用cy3标记的CD31抗体使细胞显现了红色荧光。 结论：转染后的骨髓间充质干细胞细胞表型发生明显转变，CD31表达率明显增高，呈现典型的内皮细胞的表型特征，这说明骨髓间充质干细胞具有向内皮细胞分化的潜能。     

Use of parenteral iron products and serious anaphylactic‐type reactions

Controversy exists about the safety of the parenteral iron dextran products, Dexferrum and INFeD, which have been associated with rare, serious anaphylactic‐type reactions. In the United States, their product labels carry boxed warnings of this adverse event; some have called for the withdrawal from marketing of the higher molecular weight Dexferrum. Between 2002 and 2007, sales of Dexferrum, INFeD, and iron gluconate Ferrlecit declined 32.5%, 21%, and 4.8%, respectively, while sales of iron sucrose Venofer increased 160%. Voluntary reports submitted to the Food and Drug Administration show anaphylactic reactions and symptoms for the four parenteral iron products. Because of underreporting, possible differential reporting, absence of iron dextran brand names, and incomplete use (denominator) data, incidence rates and relative risk estimates cannot be calculated. U.S. death certificate data show that for most years from 1979 through 2006, no more than 3 deaths per year were coded to “adverse events in therapeutic use of iron preparations;” brand names were not consistently recorded. Emergency department data show small numbers of visits for treatment of allergic reactions with intravenous iron preparations. The data presented herein show that allergic reactions are possible with all four parenteral iron products, and it is difficult to determine which product has the largest risk based on sales data, voluntarily submitted adverse event reports, death certificates, ED visits, and observational studies performed to date. To help differentiate risk among the parenteral iron products, the brand name of the product always should be provided on medical records, death certificates, and adverse drug reaction reports. Am. J. Hematol., 2010. Published 2010 Wiley‐Liss, Inc.     

Assessment of an abbreviated odorant identification task for children: a rapid screening device for schools and clinics

To validate the level of olfactory performance of children, we tested 825 volunteers, aged 4–17 years, with an abbreviated form of our pediatric odorant identification task. The test consisted of sniffing and identifying five odorants (baby powder, bubble gum, candy cane, licorice and peach). Mean olfactory scores increased as a function of age, reaching a plateau of about 94–95% correct at 8 years of age. In general, girls out–performed boys. Physicians require a test instrument such as the one we have devised to allow them to diagnose olfactory dysfunction in children. The present task is particularly applicable in screening large numbers of children in clinics or schools because it can be administered easily and rapidly. Adult subjects with olfactory dysfunction also performed poorly on this odorant identification task designed for children. Therefore, we expect that our odorant identification task will also detect children with severe olfactory dysfunction.     

Colorectal hemangioma: radiologic findings

The authors correlated radiographs with the clinical and histologic data of 12 patients with colorectal hemangioma. All patients presented with rectal bleeding, which was chronic in seven. Phleboliths were also visible in seven cases, which correlated with chronic bleeding in five. On barium studies, three masses were soft and three produced rigid narrowing. The atypical features of rigid luminal narrowing, which might mimic a carcinoma, and hypovascularity correlated with chronic bleeding or visible phleboliths, which suggest the correct diagnosis of colorectal hemangioma.