多孔双向羟基磷灰石人工骨治疗四肢骨缺损49例

目的 通过临床应用多孔双向羟基磷灰（ＣＰＣ）石人工骨,讨论其成骨机制、影像学表现、适应证和存在的问题。方法 对４９例不同情况骨缺损植入颗粒状或片、块状ＣＰＣ,经摄Ｘ线片和γ骨显像检查,观察其愈合过程中的表现。结果 全部病例平均随访２．５年。腔洞型骨缺损者术后３个月愈合,小关节融合术者术后４～７个月愈合,骨不连者术后５～７全月愈合,全部病例手术局部无炎症反应。结论 ＣＰＣ是一种比较成熟的骨修复材料,     

液相色谱法测定小鼠脑组织中ATP、ADP及AMP含量

目的建立小鼠脑组织中腺苷酸含量测定的高效液相色谱(high performance liquid chromatogram,HPLC)-可变波长检测法。方法应用酸沉淀蛋白、Agilent1200高效液相色谱系统、Supelco Discovery C18(150 mm×4.6 mm,5μm)反相色谱柱及相同填充材料的预柱,对小鼠脑组织样品中腺苷酸进行分离分析,波长为254 nm,流动相为30 mmol/L K2HPO4-KH2PO4(含5%甲醇),pH5.85,流速为1.0 mL/min,进样体积为20μL,柱温为30℃。结果腺苷酸ATP、ADP及AMP在10～100 mg/L范围,线性关系良好,线性方程为ATP:A=28.924C+14.144,γ=0.999 90;ADP:A=31.504C-12.608,γ=0.999 92;AMP:A=46.539C-5.255,γ=0.999 95。平均回收率为95.3%～103.2%;日内和日间相对标准差(RSD)分别为1.14%～1.75%、2.45%～3.97%。结论高效液相色谱-可变波长检测法可以简便、准确、有效地测定急性重复低氧小鼠脑组织中ATP、ADP和AMP的含量。     

酪蛋白磷酸肽-磷酸钙溶液抑制牛牙早期釉质龋的体外研究

目的 研究酪蛋白磷酸肽-磷酸钙溶液(CPP-ACP)在体外对牛牙釉质早期人工龋的抑制作用.方法 将28颗牛牙釉质样本随机分成4组,每组7颗,浸入唾液24 h以形成人工获得性膜,然后用4种不同溶液(A组:去离子水;B组:1% CPP-ACP溶液;C组:0.05%的NaF溶液;D组:1% CPP-ACP和0.05% NaF...     

用双试剂与日立7170A分析仪测定血清无机磷

用日立７１７０Ａ分析仪以双试剂测定血清无机磷，并观察异常蛋白引起的干扰。该法线性范围可达５ｍｍｏｌＬ－１，准确度和精密度系数均在９５％以上，回收率在９８．２％～９９．５％之间，脂浊血清及黄疸血清对本法不产生干扰。双试剂与多发性骨髓瘤病人血清（含异常蛋白）不产生沉淀，是一种理想的血清无机磷测定法。     

In vitro neurotoxic hazard characterization of different tricresyl phosphate (TCP) isomers and mixtures

Exposure to tricresyl phosphates (TCPs), via for example contaminated cabin air, has been associated with health effects including the so-called aerotoxic syndrome. While TCP neurotoxicity is mainly attributed to ortho-isomers like tri-ortho-cresyl phosphate (ToCP), recent exposure and risk assessments indicate that ToCP levels in cabin air are very low. However, the neurotoxic potential of non-ortho TCP isomers and TCP mixtures is largely unknown. We therefore measured effects of exposure (up to 48 h) to different TCP isomers, mixtures and the metabolite of ToCP (CBDP: cresyl saligenin phosphate) on cell viability and mitochondrial activity, spontaneous neuronal electrical activity, and neurite outgrowth in primary rat cortical neurons.The results demonstrate that exposure to TCPs (24–48 h, up to 10 μM) increases mitochondrial activity, without affecting cell viability. Effects of acute TCP exposure (30 min) on neuronal electrical activity are limited. However, electrical activity is markedly decreased for the majority of TCPs (10 μM) following 48 h exposure. Additional preliminary data indicate that exposure to TCPs (48 h, 10 μM) did not affect the number of neurites per cell or average neurite length, except for TmCP and the analytical TCP mixture (Sigma) that induced a reduction of average neurite length.The combined neurotoxicity data demonstrate that the different TCPs, including ToCP, are roughly equipotent and a clear structure-activity relation is not apparent for the studied endpoints. The no-observed-effect-concentrations (1 μM) are well above current exposure levels indicating limited neurotoxic health risk, although exposures may have been higher in the past. Moreover, prolonged and/or repeated exposure to TCPs may exacerbate the observed neurotoxic effects, which argues for additional research.     

高能量胫骨平台骨折的手术治疗

目的探讨高能量损伤胫骨平台骨折手术治疗效果。方法从1995年8月至2004年7月收治高能量胫骨平台骨折患者32例。骨折按Schatzker分型：Ⅳ型骨折10例,Ⅴ型骨折14例,Ⅵ型骨折8例。采用切开复位内固定治疗,骨缺损者同时予以植骨。结果经6～24个月随访,平均13个月。32例均全部愈合。按Hiss膝关节临床功能评分[1]为78.6分。结论胫骨平台高能量胫骨平台骨折宜手术治疗,但必须着重于选择手术时机、坚强的内固定,尽量维持正常的力轴线,确保关节稳定,早期积极处理合并伤,早期的膝关节功能锻练。     

吐温-80增敏光度法测定食品中复合磷酸盐

目的：建立测定复合磷酸盐的新方法。方法：在硫酸介质中,吐温-80存在下,基于磷酸盐与钼酸铵反应,生成黄色络合物,据此建立测定磷酸盐的光度法。结果：线性范围为0～8μg/ml,检出限为0.10μg/ml。结论：方法应用于食品中微量磷酸盐含量测定,结果满意。     

Maintenance of PtdIns45P2 pools under limiting inositol conditions,as assessed by liquid chromatography-tandem mass spectrometry and PtdIns45P2 mass evaluation in Ras-transformed cells

Inositol-containing molecules are involved in important cellular functions, including signalling, membrane transport and secretion. Our interest is in lysophosphatidylinositol and the glycerophosphoinositols, which modulate cell proliferation and G-protein-dependent activities such as adenylyl cyclase and phospholipase A₂. To investigate the role of glycerophosphoinositol (GroPIns) in the modulation of Ras-dependent pathways and its correlation to Ras transformation, we employed a novel liquid chromatography-tandem mass spectrometry technique to directly measure GroPIns in cell extracts. The cellular levels of GroPIns in selected parental and Ras-transformed cells, and in some carcinoma cells, ranged from 44 to 925 μM, with no consistent correlation to Ras transformation across all cell lines. Moreover, the derived cellular inositol concentrations revealed a wide range (150 μM to 100 mM) under standard [³H]-inositol-loading, suggesting a complex relationship between the inositol pool and the phosphoinositides and their derivatives. We have investigated these pools under specific loading conditions, designing a further HPLC analysis for GroPIns, combined with mass determinations of cellular phosphatidylinositol 4,5-bisphosphate. The data demonstrate that limiting inositol conditions identify a preferred pathway of inositol incorporation and retention into the polyphosphoinositides pool. Thus, under conditions of increased metabolic activity, such as receptor stimulation or cellular transformation, the polyphosphoinositide levels will be maintained at the expense of phosphatidylinositol and the turnover of its aqueous derivatives.     

Evidence of hydroxyl-ion deficiency in bone apatites: an inelastic neutron-scattering study

The novelty of very large neutron-scattering intensity from the nuclear-spin incoherence in hydrogen has permitted the determination of atomic motion of hydrogen in synthetic hydroxyapatite and in deproteinated isolated apatite crystals of bovine and rat bone without the interference of vibrational modes from other structural units. From an inelastic neutron-scattering experiment, we found no sharp excitations characteristic of the vibrational mode and stretch vibrations of OH ions around 80 and 450 meV (645 and 3630 cm⁻¹), respectively, in the isolated, deproteinated crystals of bone apatites; such salient features were clearly seen in micron- and nanometer-size crystals of pure hydroxyapatite powders. Thus, the data provide additional definitive evidence for the lack of OH⁻ ions in the crystals of bone apatite. Weak features at 160–180 and 376 meV, which are clearly observed in the apatite crystals of rat bone and possibly in adult mature bovine bone, but to a much lesser degree, but not in the synthetic hydroxyapatite, are assigned to the deformation and stretch modes of OH ions belonging to HPO₄-like species.     

In vitro effects of high-energy pulsed ultrasound on human squamous cell carcinoma cells

Human squamous cell carcinoma cells cloned from the hypopharynx (FaDu) and oral cavity (SCC-4) were exposed to high-energy pulsed ultrasound (HEPUS) in vitro to evaluate the effects of various physical parameters on cell viability. Such included the number of pulses, voltage applied, pulse repetition rate and cell density. The experimental piezoelectric ultrasound transducer used in the experiments generated pulses with a high negative pressure amplitude. By varying the repetition frequency from 0.6 to 8 Hz, cell viability was found to be least when pulse repetition was approximately 1 Hz. An increase in transducer voltage resulted in a linear decrease in cell viability. The cell survival rate dropped exponentially as a function of the number of pulses applied, reaching 4.2% after 2000 pulses. The cell survival rate exhibited no significant dependence on cell density when cells ranged from 1 to 3.5 · 10⁶ cells ml^–1. Data obtained with trypan blue dye exclusion were confirmed by measurements of intracellular lactate dehydrogenase released into an extracellular fluid supernatant. By applying HEPUS to tumor cells, almost complete destruction of the cells could be achieved in vitro. The degree of cell destruction achieved depended significantly on the number of pulses administered, the pulse repetition rate and the transducer voltage applied.