Methodologic study of direct preparation for chromosome analysis of human solid brain tumors.

Human malignant glioma grown in athymic nude mice (NHG-1) and three freshly resected human solid gliomas were used in the study of factors influencing the direct preparation (DP) for chromosome analysis of human solid tumors. The results showed that: 1) the length of time after the blood supply was obstructed was a major factor in reducing the success rate of DP, i.e., a 2-hour delay resulted in a significantly lowered metaphase number and after 4 hours almost no metaphases could be seen; 2) preserving tumor cells at 4 degrees C may prolong the time limit to about 4 hours; 3) culture medium (RPMI 1640 and Eagle MEM) and bovine calf serum concentration (0%, 10%, 20%, and 30%) did not influence the success rate significantly; 4) colchicine concentration (0.025 micrograms/mL, 0.05 micrograms/mL, 0.1 micrograms/mL) and time of treatment (30 min, 90 min, or 180 min) mainly affected the quality of chromosomes observed but had little effect on the quantity of metaphases that might be obtained. Based on these results, we had a success rate of more than 80% in 72 xenografts and 22 human brain tumors.     

电针退热时家兔的血浆及脑脊液中前列腺素E_2含量的变化

本实验用家兔复制内毒素性发热模型,观察电针退热时血浆,CSF中PGE_2含量的变化。实验结果表明:在发热高峰期,两组动物的血浆、CSF中PGE_2含量都比发热前明显升高(P<0.091)。电针对内毒素性发热有明显地抑制作用。电针组动物的血浆及CSF中PGE_2含量明显低于对照组(P<0.001)。作者推论:PGE_2是内毒素性发热的一种中枢性发热介质,电针的退热作用可能是通过一种未知方式抑制中枢PGE_2的产生或释放而实现的。     

临床分离产IMP-1型金属酶非发酵菌的耐药机制研究

从临床收集耐亚胺培南的铜绿假单胞菌和鲍曼不动杆菌共50株,进行头孢他啶和2-巯基乙醇的表型协同试验(CAZ ME),然后进行金属酶IMP-1基因的PCR检测。选取IMP-1阳性株测序,用PCR方法检测有无一类整合子基因(IntI1)。表型的检测发现有28株为协同阳性,其中铜绿假单胞菌27株,鲍曼不动杆菌1株。PCR和测序检测出其中一株铜绿假单胞菌含有IMP-1基因,同时也含有IntI1基因。首次在中国西部地区发现产IMP-1型金属酶、同时也含有一类整合子的铜绿假单胞菌,对于临床上研究细菌的耐药性传播具有重要意义。     

Autoantibodies to the high-affinity IgE receptor in children with chronic urticaria.

BACKGROUND: Chronic urticaria (CU) in childhood remains a challenge for investigation, and its etiology is largely unknown. Autoantibodies to the high-affinity IgE receptor (FcepsilonRI) are believed to play a role in the pathogenesis of this disease in adults. OBJECTIVE: To determine the prevalence of autoantibodies to FcepsilonRIalpha on basophils in children with CU vs atopic eczema dermatitis syndrome (AEDS). METHODS: Eighty children with CU were compared with 38 children with AEDS. In addition to complete blood cell counts and total IgE measurements, CAP-RASTs to egg, codfish, soy, milk, and peanut were performed. Stool samples were examined for parasites, and autologous serum skin testing and a functional anti-FcepsilonRIalpha assay were conducted to detect autoantibodies. RESULTS: No significant differences were observed between children with CU and controls in mean basophil or eosinophil counts. Twenty (26%) of 77 children with CU and 31 (82%) of 38 with AEDS had positive CAP-RAST results (P < .001). Only 2.5% of the children with CU and 0% with AEDS had stool samples positive for parasites (P = .005). Anti-FcepsilonRIalpha autoantibodies were positive in 37 (47%) of 78 children with CU and in none of 33 with AEDS. Non-IgG histamine-releasing factors were found in 10 (13%) of 78 children with CU. CONCLUSIONS: Children have a similar prevalence of autoantibodies to the FcepsilonRIalpha as has been previously published for adults. Few have type I allergies, and parasite infestation is also uncommon. Further studies are required to investigate the predictive value of the autoantibodies in these children with respect to clinical profile, requirements for medications other than antihistamines, and remission rates.     

X-linked severe combined immunodeficiency syndrome: the first Korean case with gamma c chain gene mutation and subsequent genetic counseling

X-linked severe combined immunodeficiency (X-SCID) is a rare, life-threatening immune disorder, caused by mutations in the gamma c chain gene, which encodes an essential component of the cytokine receptors for interleukin-2 (IL-2), IL-4, IL-7, IL-9, IL-15, and IL-21. A 13-month-old boy with recurrent infections who had reduced serum immunoglobulin levels and decreased numbers of CD3, CD16/56 cells was evaluated for gamma c chain gene mutation and protein expression. The patient had a C-to-T point mutation at nucleotide position 690, one of the hot spots, resulting in a single amino acid substitution of cysteine for arginine (R226C), as determined by direct sequencing and PCR-RFLP. The patient's mother was a heterozygous carrier. Percutaneous umbilical cord blood sampling was performed at the 6-month of gestation in a subsequent pregnancy. As the immunophenotype of the fetus showed an identical pattern, the pregnancy was terminated and genetic analysis of the abortus confirmed recurrence. This is the first report of the molecular diagnosis of X-SCID in Korea. Genetic analysis of the gamma c chain gene is useful for definite diagnosis and genetic counseling for X-SCID.     

大白鼠脊髓向延髓外侧网状核投射的体部定位——HRP顺行法研究

向大白鼠脊髓的颈、腰膨大和胸髓右侧半分别注入HRP或WGA—HRP,研究了脊髓向延髓外侧网状核的投射。 1.双侧的三叉神经下亚核同时接受颈、胸和腰髓来的投射。 2.大白鼠脊髓主要投射于外侧网状核的尾侧半,有一定的体部定位关系。颈髓投射于双侧大细胞亚核的外侧2/3及与共相邻接的一部分小细胞亚核内,以同侧投射为主。胸髓投射于双侧的大细胞亚核的内侧2/3和与之相邻接的一部分小细胞亚核内,两侧无明显差別。腰髓投射于双侧小细胞亚核和与之相邻接的部分大细胞亚核内,以对侧投射为主。它们相互间有部分重叠。 3.颈、胸和腰髓内外侧网状核投射的神经元位于从背角至腹角的灰质内,越边投射的神经元比不越边投射的神经元位置更靠腹侧。     

Towards practical soft X-ray spectromicroscopy of biomaterials

Scanning transmission X-ray microscopy (STXM) is being developed as a new tool to study the surface chemical morphology and biointeractions of candidate biomaterials with emphasis on blood compatible polymers. STXM is a synchrotron based technique which provides quantitative chemical mapping at a spatial resolution of 50 nm. Chemical speciation is provided by the near edge X-ray absorption spectral (NEXAFS) signal. We show that STXM can detect proteins on soft X-ray transparent polymer thin films with monolayer sensitivity. Of great significance is the fact that measurements can be made in situ, i.e. in the presence of an overlayer of the protein solution. The strengths, limitations and future potential of STXM for studies of biomaterials are discussed.