Evidence for a major gene underlying bone size variation in the Chinese

Osteoporosis is a major public health problem defined as a loss of bone strength, of which bone size is an important determinant. In the present study, familial correlation and segregation analyses for the spine and hip bone sizes were performed for the first time in a Chinese sample composed of 393 nuclear families with a total of 1,193 individuals. The results indicate a major gene of codominant inheritance for spine bone size; however, there is no evidence of a major gene influencing hip bone size. Significant familial residual effects are found for both traits, suggesting their polygenic inheritance. Heritability estimates (±SE) for spine and hip bone size were 0.62 (0.13) and 0.59 (0.12), respectively. Sex and age differences in genotype‐specific average bone size were observed. Compared with our previous study on bone mineral density (BMD) in the same population, this study suggests that genetic determination of bone size may be different from that of BMD, and thus studying bone size as one surrogate phenotype for osteoporotic fractures may be necessary. Am. J. Hum. Biol. 16:68–77, 2004. © 2003 Wiley‐Liss, Inc.     

大鼠肝抑素纯化及其生物活性的检测

用ＳｅｐｈａｄｅｃＧ－５凝胶过滤层析法，进一步纯化具肝抑素生物活性的大鼠肝蛋白质粗提品，以分离的大鼠再生肝的肝细胞为靶细胞，体外检测各洗脱峰浓缩物对肝细胞增殖的制率结果证明，Ｅ峰浓缩物的抑制作用最强，其活性比为粗提品的２０倍，ＳＤＳ聚丙烯酰胺电泳图及蛋白质迁移率测定表明，该浓缩物的主要成分为分子量１３．５ｋＤ的多肽。本研究对大鼠肝抑素做了初步纯化，验证了该物质在肝再生中起重要调控作用的生物效应。     

血液透析对转化生长因子β1及补体调节蛋白CD59基因表达的影响

目的　研究不同透析膜对维持性血液透析 (MHD)患者外周血转化生长因子 β1及补体调节蛋白CD5 9活性表达的影响。方法　通过流式细胞术和酶联免疫吸附法测定长期采用铜仿膜 (CU)与聚砜膜 (PSU)透析患者外周血TGF β1水平及CD5 9活性表达。结果　MHD患者血浆TGF β1水平明显增加 (P <0 .0 5 ) ,其中CU组为 (81.7± 8.7)ng mL ;PSU组为 (6 4 .3±8.3)ng mL ,与正常对照组 (49.3± 6 .1)ng mL相比均有显著差异 (P <0 .0 1,P <0 .0 5 ) ;而PSU组与CU组相比 ,外周血TGF β1水平明显下降 (P <0 .0 5 )。CD5 9在正常人外周血单个核细胞中无表达 ,而在尿毒症未透析组及血透组均有表达 ,其中未透析组表达较低 ,而血透组表达较高 ,CU膜血透组较PSU血透组表达要高 (P <0 .0 5 )。经相关分析结果显示 :CU组与PSU组内TGF β1水平与CD5 9表达均呈现良好的相关性 (r=0 .6 4 0 9与 0 .5 83,P <0 .0 5 )。 结论　血液透析通过血液 透析膜间相互反应可活化补体 ,诱导外周血单个核细胞 (PBMC)合成TGF β1增多 ,而增高的TGF β1水平可上调CD5 9基因表达 ,抑制补体异常活化造成的细胞破坏 ,对机体具有代偿性保护意义。然而不同透析膜如CU和PSU对MHD患者TGF β1与CD5 9的影响有所不同 ,这些变化与透析膜的生物相容性有关     

双歧杆菌脂磷壁酸延缓脾脏衰老的研究

目的　研究双歧杆菌表面分子脂磷壁酸 (LTA)在D 半乳糖诱导的衰老小鼠体内 ,对脾脏指数和脾细胞DNA损伤的影响。方法　在建立D 半乳糖诱导的衰老小鼠模型的同时 ,注射双歧杆菌LTA ;然后测定模型对照组、正常对照组、试验组小鼠的脾脏指数 ,并以单细胞凝胶电泳试验检测脾脏淋巴细胞DNA氧化损伤的情况。结果　与正常对照组相比 ,模型对照小鼠的脾脏指数显著升高 (P <0 .0 5 ) ,脾淋巴细胞DNA受到了较严重的损伤 (P <0 .0 5 ) ;用双歧杆菌LTA处理后 ,试验小鼠的脾脏指数明显下降 (P <0 .0 5 ) ,脾淋巴细胞DNA的损伤程度显著降低 (P <0 .0 5 )。结论　双歧杆菌LTA能显著抑制衰老小鼠脾脏淋巴细胞DNA的氧化损伤 ,这可能与双歧杆菌抗衰老有关。     

4E-binding protein phosphorylation and eukaryotic initiation factor-4E release are required for airway smooth muscle hypertrophy

The molecular mechanisms of airway smooth muscle hypertrophy, a feature of severe asthma, are poorly understood. We previously established a conditionally immortalized human bronchial smooth muscle cell line with a temperature-sensitive SV40 large T antigen. Temperature shift and loss of large T cause G1-phase cell cycle arrest that is accompanied by increased airway smooth muscle cell size. In the present study, we hypothesized that phosphorylation of eukaryotic initiation factor-4E (eIF4E)-binding protein (4E-BP), which subsequently releases eIF4E and initiates cap-dependent mRNA translation, was required for airway smooth muscle hypertrophy. Treatment of cells with chemical inhibitors of PI 3-kinase and mammalian target of rapamycin blocked protein synthesis and cell growth while decreasing the phosphorylation of 4E-BP and increasing the binding of 4E-BP to eIF4E, consistent with the notion that 4E-BP1 phosphorylation and eIF4E function are required for hypertrophy. To test this directly, we infected cells with a retrovirus encoding a phosphorylation site mutant of 4E-BP1 (AA-4E-BP-1) that dominantly inhibits eIF4E. Upon temperature shift, cells infected with AA-4E-BP-1, but not empty vector, failed to undergo hypertrophic growth. We conclude that phosphorylation of 4E-BP, eIF4E release, and cap-dependent protein synthesis are required for hypertrophy of human airway smooth muscle cells.     

磺化聚醚砜对光敏剂-亚甲蓝的吸附去除研究Ⅱ.磺化聚醚砜对血浆中亚甲蓝的吸附去除研究

研究了磺化聚醚砜吸附柱对血浆中亚甲蓝的吸附效果,并检测了流经吸附柱的牛血清白蛋白随时间变化的规律以及过柱前后血浆中主要生化指标的变化情况.结果:磺化聚醚砜对亚甲蓝的吸附效果明显优于聚醚砜对亚甲蓝的吸附效果;其对白蛋白的吸附较小;对血浆中主要生化指标的影响可以忽略不计.     

小白鼠腘淋巴结淋巴窦的超微结构

我们观察了幼年小白鼠腘淋巴结淋巴窦的超微结构,窦壁由腔面向外一般出3层构成:(1)一层连续的内皮;(2)由一薄层细胞间质构成的基膜;(3)一层外膜网状细胞及其扁平的突起。内皮细胞核扁圆,异染色质细小,核仁不明显,胞质极薄,含粗面内质网极少,而有大量的吞饮小泡。细胞邻接处相互重叠或嵌合,有20nm宽的间隙相隔。有的地方可见不发达的细胞连接。当巨噬细胞或淋巴细胞穿越内皮时,可出现临时性间隙,内皮边缘与穿越细胞相贴。基膜由电子透明的无定形基质及细的胶原原纤维构成。外膜网状细胞的核异染色质较多,核仁明显,胞质丰富,含许多粗面内质网而很少吞饮小泡。外膜网状细胞之间常见0.5μm宽的间隙。在窦腔内有巨噬细胞、淋巴细胞及星状的网状细胞等。由于小白鼠腘淋巴结的淋巴窦小,故窦内星形的网状细胞很少,其超微结构特点,与外膜网状细胞及淋巴组织内的网状细胞相似,在突起的切面上,常见包有小束的胶原原纤维。巨噬细胞较多,形态不规则,常贴附于内皮细胞表面,核椭圆,常有凹陷,胞质丰富,含许多溶酶体。在取材前1h,于足垫注射中国墨汁的小鼠,巨噬细胞吞噬了大量粗的墨汁颗粒。本文认为,淋巴窦壁可能具有一定的屏障作用。