硫酸镁联合亚低温治疗对大鼠局灶性脑缺血的保护作用

目的　探讨硫酸镁对SD大鼠局灶性脑缺血损伤的保护作用。方法　将 4 0只大鼠随机分成模型对照组、硫酸镁治疗组、亚低温治疗组、硫酸镁联合亚低温治疗组。采用线栓法建立大鼠局灶性脑缺血模型。通过计算大鼠神经功能缺陷评分 ,测量脑梗死体积 ,观察神经元超微结构改变 ,评定硫酸镁联合亚低温治疗作用。结果各治疗组大鼠神经功能评分及脑梗死体积均显著低于对照组 (P <0 0 5 ) ,联合治疗组大鼠明显低于对照组 (P<0 0 1) ;联合治疗组神经元超微结构改变轻微。结论　硫酸镁联合亚低温治疗对大鼠局灶脑缺血有明显保护作用     

Quinine overdose: review of toxicity and treatment

Quinine sulfate is a commonly prescribed remedy for idiopathic nocturnal leg cramps and is now available "over the counter." A 24-year-old man ingested 8 g (a commonly dispensed quantity) of quinine sulfate in a suicide attempt. Despite hemoperfusion begun 10 h after ingestion, the patient died. This report reviews the toxic manifestations of quinine and the currently available modes of treatment.     

硫酸镁雾化吸入辅助治疗对重症毛细支气管炎患儿气道阻力、肺功能及炎症因子的影响

目的 观察硫酸镁雾化吸入辅助治疗对重症毛细支气管炎患儿气道阻力、肺功能及炎症因子的影响。方法 选择于医院治疗的重症毛细支气管炎患儿88例,以随机数字表法分组,44例患儿为探究组,采用硫酸镁雾化吸入辅助常规治疗,44例患儿为参照组,采用常规治疗,两组患儿均连续治疗7 d,治疗前、后检测两组患儿炎症指标：肿瘤坏死因子α(tumor necrosis factor-α,TNF-α)、可溶性血管细胞黏附分子1(soluble vasccular cell adhesion molecule-1,sVCAM-1)、Nod样受体蛋白3(Nod-like receptor pyrin domain3,NLRP3)、嗜酸粒细胞阳离子蛋白(eosinophil cationic protein, ECP)水平：气道阻力指标：近端气道黏性阻力(R20)、气道总阻抗(Z5)、气道总黏性阻力(R5)、肺神经源性P物质水平;肺功能指标：有效呼吸道阻力(Reff)、第1秒用力呼气容积(forced expiratory volume in one second, FEV1)、最大呼气中段流量(maximal mi...     

Interactions of γ-immunoglobulins with lipid mono- or bilayers and liposomes. Existence of two conformations of γ-immunoglobulins of different hydrophobicities

Interactions between rabbit-γ-immunoglobulins and model membranes (lipid monalayers, planar lipid bilayers, liposomes) have been investigated. No significant interaction was observed with immunoglobulins. However, immunoglobulins dialysed first vs aqueous buffer having pH 2 or 3 and then dialysed against pH 7 buffer presumably adopt a new conformation which allows their bindings to model membranes. This binding is hydrophobic and the immunoglobulin region interacting with the lipid acyl chains is probably located in the heavy chain, as suggested by labelling in this region by a photosensitive probe previously incorporated into the lipid hydrophobic core. Cleavage at the hinge region by papain or pepsin, or heating above 38°C, induces the loss of the hydrophobic conformation responsible for hydrophobic bindings. The binding capacity of immunoglobulins heated above 38°C is restored after momentary dialysis at pH 2. The possible existence of two Ig isomers is discussed in relation to the mechanism of γ-immunoglobulin passage through the endoplasmic membrane and fixation into the plasma membrane.     

Histidine-rich protein genes and their transcripts in Plasmodium falciparum and P. lophurae

The presence of histidine-rich protein (HRP) related genes and gene products in Plasmodium falciparum was demonstrated using a synthetic pentahistidine-encoding oligonucleotide and a cloned HRP cDNA probe prepared from the avian parasite P. lophurae. In Northern blotting experiments, two knobby clones of P. falciparum were found to contain a 3500 nucleotide RNA species that hybridized with the oligonucleotide and HRP cDNA probes. As this component had the expected size for an mRNA encoding an 80-90 kDa protein and was absent from two knobless clones of P. falciparum, we concluded that it represented a 'knob protein' mRNA. Using the restriction enzyme EcoRI, three identical cross-hydribizing HRP gene fragments were found in the DNA of both knobby and knobless clones of P. falciparum. These fragments differed in size from those present in P. lophurae. These results suggest that the absence of knob protein mRNA in knobless clones is not due to loss of the corresponding gene(s).     

Immunocytochemistry of keratan sulfate proteoglycan and dermatan sulfate proteoglycan in porcine tooth-germ dentin

Keratan sulfate proteoglycan and dermatan sulfate proteoglycan have been reported to inhibit collagen fibrillogenesis. We investigated their distribution in order to evaluate the role of proteoglycan in dentinogenesis. Specimens of porcine tooth-germ dentin and erupted teeth were the materials on which antibodies to keratin sulfate and dermatan sulfate proteoglycan were used. Predentin was found to be positive for both antibodies and the reaction ceased in the calcification front. Uniformly thick collagen fibrils (30-70 nm in diameter) were distributed in the predentin matrix, which would become intertubular dentin in the future. Both antibodies reacted positively along these fibrils. In contrast, along the surface layer of dentin in the tooth germ and that in erupted teeth, collagen fibrils of 10-300 nm in diameter were noted occasionally in dentinal tubules whose odontoblastic processes had disappeared and these heterogeneous fibrils were negative for both antibodies. Our findings suggest that keratan sulfate proteoglycan and dermatan sulfate proteoglycan distributed in the predentin inhibit calcification of collagen fibrils in the uncalcified matrix and disappear in the calcification front. It is further suggested that keratan sulfate proteoglycan and dermatan sulfate proteoglycan distributed along collagen fibrils in the predentin matrix maintain uniform thickness, whereas collagen fibrils in dentinal tubules varied in thickness because of the absence of involvement of both proteoglycans. Therefore, keratan sulfate proteoglycan and dermatan sulfate proteoglycan were thought to be involved in both calcification and matrix formation.     

硫酸软骨素酶ABC对大鼠脊髓损伤修复的影响

为了探讨硫酸软骨素酶ABC对脊髓损伤后损伤局部瘢痕形成和脊髓传导功能修复的影响,本研究首先制作大鼠脊髓全横断损伤动物模型,并将其分为脊髓损伤组(A组)和脊髓损伤治疗组(B组)。在观察期内对动物的行为学表现进行BBB评分;用免疫荧光组织化学方法观察损伤4周后硫酸软骨素酶ABC对损伤局部的硫酸软骨素蛋白聚糖(CSPGs)的裂解作用;用辣根过氧化物酶(HRP)示踪法观察损伤8周后神经纤维的再生情况。结果显示:A组与B组之间动物的行为学评分B组优于A组,有显著性差异(P<0.01);B组动物脊髓内硫酸软骨素蛋白聚糖阳性物质的表达明显低于A组,具有显著性差异(P<0.05),而硫酸软骨素核心蛋白的表达无显著性差异(P>0.05);HRP示踪法显示B组脊髓损伤头端可见少量HRP标记的神经元胞体和纤维。本研究结果提示硫酸软骨素酶ABC能够裂解CSPGs中的葡胺聚糖链,减少瘢痕,促进损伤的神经纤维再生。     

Inhibition of experimental metastasis and cell adhesion of murine melanoma cells by chondroitin sulfate-derivatized lipid, a neoproteoglycan with anti-cell adhesion activity

Chondroitin sulfate dipalmitoylphosphatidylethanolamine (CS-PE), when immobilized onto substratum, inhibited the adhesion of B16F10 mouse melanoma cells to fibronectin-coated dishes (anti-adhesion activity). CS-PE showed the most potent anti-adhesion activity for the melanoma cells among various GAG-PEs. CS-PE also inhibited the adhesion of B16F10 cells to Matrigel and the invasion of the cells into Matrigel. In the in vivo system of experimental metastasis, administration of B16F10 cells with CS-PE into C57BL/6 mice significantly inhibited lung metastasis. The inhibition degree of CS or hyaluronic acid-PE was lower than CS-PE. CS-PE administered intravenously into mice before the injection of B16F10 cells also inhibited metastasis. Pretreatment of B16F10 cells with CS-PE caused some but a lower degree of inhibition. When CS-PE was injected intravenously into mice, more binding in the lung was found than when CS was injected. CS-PE but not CS inhibited the retention in the lung of fluorochrome-labeled B16F10 cells when injected intravenously into mice. Since there was no significant effect of CS-PE on the viability and growth of B16F10 cells, the results suggest that CS-PE immobilized onto the subendothelial matrix may prevent melanoma cells from adhering to the subendothelial substrata of lung capillaries and inhibit subsequent invasion processes of metastasis.     

Characterization of a monoclonal anti-Bw4 antibody (Tü109): Evidence for similar epitopes on the Bw4 and Bw6 antigens

The production and serologic, as well as immunochemical properties of a cytotoxic murine IgG monoclonal antibody (Tü109) that precipitates HLA-class I molecules, are described. In the microcytotoxicity assay Tü109 supernatant was demonstrated on a panel of 424 HLA-ABC, -DR, -DQ, -MT typed normal Caucasian blood donors to define an epitope on HLA-B locus molecules in great association with the supertypic specificity Bw4. Reactivity of supernatant showed MHC linked inheritance of the Tü109 determinant and discriminated the HLA-Bw4/Bw6 associated HLA-B locus split antigens. Weak or lack of binding on lymphocytes from some HLA-Bw4 heterozygous individuals, particularly typing for HLA-Bw44, appeared to be due to qualitative and/or quantitative variations of HLA-B locus molecules on the cell surface. With Tü109 ascites fluid, however, extra-reactivity on all HLA-Bw6⁺ cells was demonstrated. Preferential binding of supernatant to HLA-Bw4, but reactivity of ascites fluid with HLA-Bw6⁺ molecules in addition, was furthermore confirmed by IEF analysis of antigens immunoprecipitated with Tü109 from cell lysates. Thus the antibody may help to analyze the evolutionary relationship of the diallelic specificities Bw4 and Bw6.     

Redundant function of the heparan sulfate 6-O-endosulfatases Sulf1 and Sulf2 during skeletal development

Modification of the sulfation pattern of heparan sulfate (HS) during organ development is thought to regulate binding and signal transduction of several growth factors. The secreted sulfatases, Sulf1 and Sulf2, desulfate HS on 6-O-positions extracellularly. We show that both sulfatases are expressed in overlapping patterns during embryonic skeletal development. Analysis of compound mutants of Sulf1 and Sulf2 derived from gene trap insertions and targeted null alleles revealed subtle but distinct skeletal malformations including reduced bone length, premature vertebrae ossification and fusions of sternebrae and tail vertebrae. Molecular analysis of endochondral ossification points to a function of Sulf1 and Sulf2 in delaying the differentiation of endochondral bones. Penetrance and severity of the phenotype increased with reduced numbers of functional alleles indicating redundant functions of both sulfatases. The mild skeletal phenotype of double mutants suggests a role for extracellular modification of 6-O-sulfation in fine-tuning rather than regulating the development of skeletal structures.