X连锁无汗性外胚叶发育不全家系ED1基因的突变检测

目的探讨国内X连锁无汗性外胚叶发育不全家系中ED1基因的突变情况，为该病的遗传咨询、产前诊断、确诊携带者提供依据。方法收集2个X连锁无汗性外胚叶发育不全家系及1个散发患者的外周血样本，盐析法提取基因组DNA，采用聚合酶链反应（polymerase chain reaction，PCR）和直接测序对ED1基因进行突变检测。结果家系一患者ED1基因第9外显子发生错义突变（1045G〉A），家系二和散发患者ED1基因第3外显子发生错义突变，分别为467G〉A和466C〉T。结论ED1基因的错义突变可导致X连锁无汗性外胚叶发育不全。这3个突变与国外学者的报道一致。     

A comparative study of sialic acid-rich proteins in rat bone and dentin

Four sialic acid-rich (SA-rich) proteins found in bone and dentin, osteopontin (OPN), bone sialoprotein (BSP), bone acidic glycoprotein-75 (BAG-75), and dentin matrix protein 1 (DMP1), share some common features. We used SDS-PAGE and Western immunoblots to analyze and compare SA-rich proteins in bone and dentin extracts from rats with a single chromatographic procedure. OPN was detected in dentin extracts, with a relative level less than one-seventieth of that in bone. Both bone and dentin BSP demonstrated an extremely broad distribution pattern, probably due to a high degree of heterogeneity in post-translational modifications. BAG-75 in both bone and dentin was detected as an 83 kDa band, dramatically distinct from that of DMPI. Using a polyclonal antibody raised against a purified bone 57 kDa protein (a portion of DMPI), we detected 150 kDa protein bands in bone fraction; the same bands were recognized by antirecombinant rat DMPI antibody. Bands from dentin migrating at about 150 kDa in earlier fractions and progressing to 200 kDa in later fractions showed a clear immunoreactivity to the anti-57 kDa antibody. We conclude that the majority of DMPI in rat bone is processed into fragments, whereas that in dentin remains intact.     

Differential in situ distribution of interleukin-8, monocyte chemoattractant protein-1 and Rantes in human chronic periapical granuloma

In situ distribution of three prototype chemokines interleukin (IL)-8, monocyte chemoattractant protein (MCP)-1 and Rantes was determined in chronic human periapical granulomas by immunohistochemistry using monoclonal antibodies. IL-8 was found primarily in the cytoplasm of the Malassez epithelial cells. MCP-1 immunoreactivity was confined to the endothelial cells that lined small venules. Each of the three investigated chemokines, including Rantes, exhibited a characteristic binding pattern to the extracellular matrix of the lesion. The observed chemokines may play a role in establishing the cellular composition of chronic apical periodontitis, thus augmenting the intensity of local inflammation and tissue damage.     

维生素D3衍生物对人成骨细胞生长和碱性磷酸酶活性的影响

目的：使用人胎成骨细胞（ＯＢ）为体外模型，观察了１，２５－双羟维生素Ｄ３〔１，２５（ＯＨ）２Ｄ３〕、２４，２５－双羟维生素Ｄ３［２４，２５（ＯＨ）２Ｄ３）］对ＯＢ生长和代谢的影响。方法：用ＡＬＰ测定法和Ｂｒａｄｆｏｒｄ蛋白含量法。结果：１，２５（ＯＨ）２Ｄ３在浓度为１０８ｍｏｌ／Ｌ时，刺激碱性磷酸酶（ＡＬＰ）的活性。但抑制ＯＢ的生长。２４，２５（ＯＨ）２Ｄ３在１０－８ｍｏｌ／Ｌ时无上述作用。结论：１，２５（ＯＨ）２Ｄ３对ＯＢ的ＡＬＰ有直接的促活作用，其作用与时间相关。２４，２５（ＯＨ）２Ｄ３对ＯＢ的ＡＬＰ活性无关。１，２５（ＯＨ）２Ｄ３对人胎ＯＢ生长有抑制作用。     

Gingival fibroblast response to cyclosporin A and transforming growth factor β1

This study investigates a potential role for TGFβ₁ in the pathogenesis of cyclosporin A-induced gingival overgrowth (CsA-OG). TGFβ₁ was localized immunohistochemically in the connective tissue of both normal gingiva and CsA-OG. Intense staining for TGFβ₁ was detected at the tips of the dermal papillae of the overgrown gingiva. In addition, fibroblasts derived from healthy gingiva and fibroblasts derived from CsA-OG were cultured both as monolayers or embedded in a 3D-collagen gel. Fibroblast activity was monitored in terms of protein and collagen production in the presence of (i) 1 ng/ml TGFβ₁ (ii) 500 ng/ml CsA, or (iii) 500 ng/ml CsA and 1 ng/ml TGFβ₁. In monolayer culture TGFβ₁ significantly increased protein and collagen production in all cell strains (p<0.05); however, there was no difference in response between fibroblasts from overgrown and healthy tissue. The production of both protein and collagen was significantly lower in the presence of the combination of CsA and TGFβ₁ when compared with the maximal stimulation produced by TGFβ₁ alone. In gel, TGFβ₁ significantly elevated matrix production by all overgrown cell strains (p<0.05) but had little or no effect on the normal cell strains. The combination of CsA and TGFβ₁ in gel cultures reduced protein and collagen production by overgrown cell strains compared with TGFβ¹ alone. It is concluded that the cellular activity of gingival fibroblasts is dependant on culture conditions and that fibroblasts derived from overgrown gingival tissue are more responsive to TGFβ₁ than normal gingival fibroblasts when cultured in type I collagen gel.     

Comparison of physical properties of polycarboxylate-based and conventional root canal sealers.

Several physical properties of nine commercial root canal sealers were evaluated in vitro and were compared with those of two experimental endodontic materials based on polycarboxylate formulations. Flow, setting time, compressive strength, radiopacity, adhesion to root dentin, and solubility were evaluated. The zinc oxideeugenol root canal sealers were typically of low strength and high solubility. These sealers and the Diaket polyvinyl resin sealer showed no adhesion to dentin. The epoxy resin AH26 showed superior properties with respect to strength, flow, radiopacity, and adhesion; solubility of this material was high. The polycarboxylate formulation showed significantly higher values over the commercial sealers in properties of strength, adhesion, and reduced solubility. The tensile adhesive bond strength of the polycarboxylate to root dentin was twice that of AH26. A wide variation in properties of the commercial materials tested showed the empirical nature of these "sealers." Further testing of polycarboxylate endodontic sealers is indicated.     

Effect of tube feeding on hippocampal-dependent memory in SAMP1 mice

This study examined the effect of tube feeding on hippocampal Fos induction and spatial performance in a water maze task in senescenceaccelerated mice (SAMP1). Tube feeding accelerated the age-related decline in spatial memory and decreased Fos induction in the hippocampal CA1 region in aged SAMP1 mice. The results suggest that tube feeding in aged SAMP1 mice reduces input activity in the hippocampus, thereby leading to senile memory deficits.