低温保存内生致热原对其致热活性的影响

本实验用家兔全血加精制大肠杆菌内毒素，体外培养提取粗制家兔内生致热原。给大鼠静脉注射复制发热模型，观察了不同温度保存和不同时间保存的ＥＰ对其致热活性的影响。结果表明：４℃保存３天，－４０℃保存３天，７天，３０天和１８０天的ＥＰ与４℃保存１天的ＥＰ比较，其发热第一时相发热峰值和１小时体温反应指数均无显著性差异（Ｐ＜０．０５）。发热第二时相△Ｔ和第二时相１小时ＴＲＩ，在４℃保存３天和－４０℃保存３天，     

Multiblock poly(ether-ester-amide)s based on polyamide-6 and poly(ethylene glycol), 2 Effect of composition and soft-segment length on the structure of poly(ether-ester-amide)s as revealed by X-ray scattering

Isotropic unannealed and annealed melt-pressed and quenched samples of segmented multiblock poly(ether-ester-amide)s based on polyamide-6 and poly(ethylene glycol)s (PEGs) of molecular weights 400 and 1000 with various hard/soft segment weight ratios were investigated. The effect of composition, segment length and annealing temperature on the crystal structure was studied by differential scanning calorimetry, wide-angle and small-angle X-ray scattering. In addition to the γ-phase, one of the unannealed samples having relatively long hard and soft segments exhibits a high amount of α-phase. This is assumed to be due to the high flexibility of the PEG segments, linking the polyamide blocks thus enhancing their mobility. The lack of hydrogen bonds between the PEG segments facilitates crystallization of the polyamide segments in the more perfect α-modification, which is the most pronounced in the above mentioned sample. Part of the α-phase transforms into the α-phase upon annealing in all copolymer samples studied, similarly to polyamide-6.     

Pathologic features of the femoral head in Mseleni disease

Severe but atypical osteoarthritic deformities were found in each of 12 femoral heads removed during total hip arthroplasty for Mseleni disease. Although degenerative and regenerative changes were present throughout the cartilage, there was a paucity of eburnation. Histomorphometric analysis of bone at the line of excision indicated that mild osteomalacia was present in four of the 12 specimens. The percentage of the endosteum occupied by osteoid was 9.7 +/- 7.96 (SD) in the patients with Mseleni disease, compared with 5.6 +/- 4.33 in seven African black and 4.1 +/- 2.13 in 13 American white control subjects. The mean thickness of the osteoid seams was not increased. The findings suggest that osteomalacia is not a major pathogenetic factor in Mseleni disease.     

STAT3 couples with 14-3-3σ to regulate BCR signaling,B-cell differentiation,and IgE production

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云南省傣族G6PD一个家系的突变型研究

在调查云南少数民族Ｇ６ＰＤ缺乏症时，采用Ｇ６ＰＤ硝基四氮唑蓝纸片法筛查，按ＷＨＯ标准化方法进行生化变异型鉴定，再用错配碱基ＰＣＲ引入酶切位点法进行ＤＮＡ突变型研究，首次在傣族中发现Ｇ６ＰＤｃＤＮＡ突变型：１３８８Ｇ→Ａ。     

Sequence diversity of the nucleoprotein gene of iris yellow spot virus (genus Tospovirus, family Bunyaviridae) isolates from the western region of the United States

Summary. Iris yellow spot virus (IYSV), a tentative virus species in the genus Tospovirus and family Bunyaviridae, is considered a rapidly emerging threat to onion production in the western United States (US). The present study was undertaken to determine the sequence diversity of IYSV isolates from infected onion plants grown in California, Colorado, Idaho, Oregon, Utah and Washington. Using primers derived from the small RNA of IYSV, the complete sequence of the nucleoprotein (NP) gene of each isolate was determined and the sequences compared. In addition, a shallot isolate of IYSV from Washington was included in the study. The US isolates of IYSV shared a high degree of sequence identity (95 to 99%) with one another and to previously reported isolates. Phylogenetic analyses showed that with the exception of one isolate from central Oregon and one isolate from California, all the onion and shallot isolates from the western US clustered together. This cluster also included onion and lisianthus isolates from Japan. A second distinct cluster consisted of isolates from Australia (onion), Brazil (onion), Israel (lisianthus), Japan (alstroemeria), the Netherlands (iris) and Slovenia (leek). The IYSV isolates evaluated in this study appear to represent two distinct groups, one of which largely represents isolates from the western US. Understanding of the population structure of IYSV would potentially provide insights into the molecular epidemiology of this virus.     

A novel active L1 retrotransposon subfamily in the mouse

Unlike human L1 retrotransposons, the 5' UTR of mouse L1 elements contains tandem repeats of approximately 200 bp in length called monomers. Multiple L1 subfamilies exist in the mouse which are distinguished by their monomer sequences. We previously described a young subfamily, called the T(F) subfamily, which contains approximately 1800 active elements among its 3000 full-length members. Here we characterize a novel subfamily of mouse L1 elements, G(F), which has unique monomer sequence and unusual patterns of monomer organization. A majority of these G(F) elements also have a unique length polymorphism in ORF1. Polymorphism analysis of G(F) elements in various mouse subspecies and laboratory strains revealed that, like T(F), the G(F) subfamily is young and expanding. About 1500 full-length G(F) elements exist in the diploid mouse genome and, based on the results of a cell culture assay, approximately 400 G(F) elements are potentially capable of retrotransposition. We also tested 14 A-type subfamily elements in the assay and estimate that about 900 active A elements may be present in the mouse genome. Thus, it is now known that there are three large active subfamilies of mouse L1s; T(F), A, and G(F), and that in total approximately 3000 full-length elements are potentially capable of active retrotransposition. This number is in great excess to the number of L1 elements thought to be active in the human genome.     

全髋关节置换术均衡双下肢长度的探讨

目的探讨全髋关节置换术均衡双下肢长度的临床意义和手术设计。方法回顾分析2000-2004年获得随访的单侧全髋关节置换手术病例48例,采用骨水泥型假体12髋,混合型假体36髋,术前双下肢等长30例(含股骨颈骨折患者),10例患肢长度短缩1.0-2.0cm,6例短缩2.0-4.0cm,2例短缩4.0-6.0cm。通过术前肢体长度测量及X片测量制定手术方案,选择假体、预估颈长和截骨平面;术中正确磨削髋臼,寻找最佳旋转中心,结合透视及特殊试验修正截骨平面,调节假体颈长,达到均衡双下肢长度的目的。结果全部病例采用Harris评分,优30例,良12例,中4例,差2例。术前等长30例巾术后出现5例手术侧延长1.0-2.0cm,1例延长2.5cm。术前不等长的18例中,术后恢复等长10例,6例手术侧延长1.0-2.0cm,2例术前重度短缩的先天性髋关节发育不良病人术后仍然短缩2.0-3.0cm。术后肢体等长35例Harris评分平均92.3分,术后肢体不等长13例Harris评分平均88.6分。结论全髋关节置换术的手术设计。手术技巧以及假体设计等诸多因素影响下肢长度,术后肢体不等长降低了患者的满意度。应重视术前测量及术中综合评价方法的运用,重视软组织平衡技术和肢长调节,掌握全髋置换术中均衡下肢长度的手术技术,进一步改善手术效果。     

Age-dependent and iron-independent expression of two mRNA isoforms of divalent metal transporter 1 in rat brain

The DMT1(Nramp2/DCT1) is a newly discovered proton-coupled metal-ion transport protein. The cellular localization and functional characterization of DMT1 suggest that it might play a role in physiological iron transport in the brain. In the study, we evaluated effects of dietary iron and age on iron content and DMT1 expression in four brain regions: cortex, hippocampus, striatum, substantia nigra. Total iron content in all regions was significantly lower in the low-iron diet rats and higher in the high-iron diet rats than that in the control animals, showing that dietary iron treatment for 6-weeks can alter brain iron levels. Contrary to our expectation, there was no significant alternation in DMT1(+IRE) and (-IRE) mRNA expression and protein content in all brain regions examined in spite of the existence of the altered iron levels in these regions after 6-weeks' diet treatment although TfR mRNA expression and protein level were affected significantly, as was expected. The data demonstrates that expression of DMT1(+IRE) and (-IRE) was not regulated by iron in these regions of adult rats. The lack of response of DMT1 to iron status in the brain suggests that the IRE of brain DMT1 mRNA might be not really iron-responsive and that DMT1-mediated iron transport might be not the rate-limiting step in brain iron uptake in adult rats. Our findings also showed that development can significantly affect brain iron and DMT1(+IRE) and (-IRE) expression but the effect varies in different brain regions, indicating a regionally specific regulation in the brain.     

Ⅲ型胶原肾小球病的形态学观察

目的了解Ⅲ型胶原肾小球病的形态学改变,并对Ⅲ型胶原可能的细胞来源进行初步探讨。方法对3例肾活检组织进行光镜、免疫荧光、电镜和Ⅰ、Ⅲ、Ⅳ型胶原及d平滑肌肌动蛋白(α-SMA)的免疫组织化学染色(SP法)观察。结果2例患者临床表现为肾病综合征,其中1例伴高血压,第3例表现为肾功能不全和肾性高血压。3例均无肾病家族史。光镜检查可见肾小球基膜内和系膜区弥漫性过碘酸-希夫反应阳性物质沉积,系膜细胞无明显增生。电镜检查在基膜内疏松层和系膜区可见大量胶原纤维沉积,系膜细胞胞膜下平行排列的束状微丝明显增加。免疫组织化学显示这些胶原纤维为Ⅲ型胶原,Ⅰ型和Ⅳ型胶原阴性,同时系膜区多数系膜细胞α-SMA阳性。结论Ⅲ型胶原肾小球病光镜、电镜及免疫组织化学上都有其特殊的病理改变。肾小球内激活的系膜细胞可能是Ⅲ型胶原的来源。