非程控降温,—80℃冻存自体外周血干细胞的研究

目的：观察非程控降温、－80℃冻存的方法对自体外周血十细胞（APBSC）的保存效果。方法：以6％羟乙基淀粉（HES）、5％二甲基亚砜（DMSO）及4％人血白蛋白（ALB）的混合物为冷冻防护剂，将APBSC直接置于－80℃下保存，冻存前反复苏后测定APBSC的CFU－GM、BFU－E；观察移植后造血功能重建情况。结果：13例患者白细胞在十3～＋7天下降至（0．0～0．1）×10／L，白细胞（0．0～0．2）×109／L持续时间3～6天，于＋9～＋11天恢复至1．0X109／L以上．中性粒细胞绝对值（ANC）于＋9～＋11天达到0．5X109／L。血小板在＋3～＋7天下降至（2．0～21）×109／L，于＋8～＋15天恢复至20×109／L以上。CFU－GM、BFU－E回大率分别为76．5％、78．4％。结论：非程控降温、－80℃冻存是一简便、经济、有效的自体外周血于细胞保存方法。     

Isolation of pathogenic bacteria from hospital staff apparel in Nigeria

A survey of bacteria contamination of hospital staff apparel in use in Anambra State, Nigeria, was carried out to determine the extent of contamination by clinically important bacteria. Of a total of 125 swab samples of hospital staff apparel, 72 (58%) showed bacterial contamination including 32 (70%) of 46 samples from hand gloves, 28 of 45 (62%) samples from protective gowns, and 12 of 34 (35%) samples from face-shields. The potentially pathogenic bacteria isolated were Salmonella spp, Proteus vulgaris, Shigella dysenteriae, Pseudomonas aeruginosa and Staphylococcus aureus. The isolation of clinically important bacteria from the apparel suggests the need for improved infection control measures.     

Mitogenicity and release of vascular endothelial growth factor with and without heparin from fibrin glue

PURPOSE: Fibrin glue (FG) has been used for local cytokine delivery on both vascular grafts and angioplasty sites. We measured the diffusive release of vascular endothelial growth factor (VEGF) and heparin from FG and the mitogenic activity of VEGF with and without heparin in FG on canine endothelial cells (ECs) and smooth muscle cells (SMCs). METHODS: Release of VEGF labeled with iodine 125 and tritiated heparin from FG into the overlying media was serially measured over 96 hours, and the data are reported as the mean percent released +/- SD. Proliferation assays measuring tritiated thymidine incorporation were performed for ECs and SMCs plated in media with 10% serum on FG containing various concentrations of VEGF and heparin. Media was placed on the FG for 24 hours and removed before plating cells to minimize the effect of the released, soluble VEGF and heparin. RESULTS: At 24 hours, 54% +/- 1% and 58% +/- 1% of the radioactive VEGF and heparin were released, respectively, with minimal release thereafter (58% +/- 1% and 66% +/- 1% at 96 hours). The ECs, SMCs, or media only (no cells) was plated on FG containing radioactive VEGF in an immediate or 24-hour delayed fashion for 72 hours to determine the percent release of VEGF into the media with the two different methods of plating. Cell type and the presence or absence of cells did not affect VEGF release, but there was three times more VEGF in the media for the immediate versus delayed plating (P <.001). Without heparin, VEGF at 100 ng/mL or more in the FG was needed to induce EC proliferation. Heparin at 5 U/mL enhanced EC proliferation at the VEGF dose of 100 ng/mL as compared wtih no heparin (P <.001), but not at the VEGF dose of 1000 ng/mL, which likely represents a maximal response. With heparin at 500 U/mL, the ECs died. In contrast, VEGF, in the presence or absence of heparin, did not affect SMC proliferation. CONCLUSIONS: We conclude that FG with VEGF at 1000 ng/mL and heparin at 5 U/mL is the optimal concentration for in vivo use because this may encourage EC, but not SMC, proliferation. The VEGF at 1000 ng/mL should leave mitogenic concentrations of VEGF intact after the initial, diffusive loss, and the addition of heparin at 5 U/mL may enhance VEGF mitogenic activity.     

白细胞介素4剪接变异体在哮喘患者中的表达

目的检测哮喘患者外周血中IL-4及其变异体IL-4δ2的表达,探讨其在哮喘发病机制中的作用。方法采用半定量RT-PCR技术,检测10例哮喘患者IL-4及其变异体的表达,并与正常健康人群进行比较。结果哮喘患者IL-4表达较健康人群高,而且IL-4和IL-4δ2的比值远远高于健康人。结论IL-4和IL-4δ2表达的相对性可能在哮喘发病机制中具有重要作用,其可能是Th2细胞在不同临床疾病中功能多样性的原因之一。     

Differences in [14C]glycerol utilization in normal and familial hypercholesterolemic fibroblasts

It is known that cultured fibroblasts from familial hypercholesterolemia (FH) patients lack the normal cell receptor for low density lipoprotein (LDL) and that the absence of receptor-mediated transport of LDL cholesterol into these cells results in increased cellular synthesis of cholesterol. After 20 h perincubation in lipid-free medium, cultured FH fibroblasts incorporated significantly greater amounts of [14C]glycerol into cellular lipids than did normal fibroblasts. Relative to the control medium which contained only bovine serum albumin (BSA), preincubation with 5% fetal bovine serum or 50 micrograms LDL/ml decreased [14C]glycerol incorporation by both cell types. FH cells utilized more [14C]glycerol for phospholipid synthesis and less for triglyceride synthesis than normal cells. This study indicates that LDL may be important in the transport of glycerides, as well as cholesterol, to cells.     

Fragile X‐associated tremor/ataxia syndrome (FXTAS) in grey zone carriers

The grey zone (GZ; 45–54 CGG repeats in the FMR1 gene) is considered a normal allele; however, several studies have found a high frequency of GZ in movement disordered populations. Here, we describe neurological features of fragile X‐associated tremor/ataxia syndrome (FXTAS) in two carriers of GZ alleles, although FXTAS has been defined as occurring only in premutation carriers (55–200 CGG repeats). Both patients had family members who had premutation and were diagnosed with FXTAS. The presence of relatively high GZ alleles with elevated fragile X mental retardation 1 mRNA (FMR1‐mRNA) combined with a family history of FXTAS that may represent a facilitating genetic background for FXTAS are the factors that led to the presence of FXTAS in these individuals with a GZ allele. Further research into clinical involvement of GZ alleles is recommended and the definition of FXTAS may require revision.