Expression of blood group antigens including HLA markers in human adult liver

The localisation of the principal blood group antigens has been studied in human liver. These blood group antigens included the erythrocyte antigens and the antigen of the major histocompatibility complex. This study was performed by the indirect immunofluorescence technique using polyclonal antibodies of human or animal origin and monoclonal antibodies from hybridomas. This study has shown that the normal hepatocyte is lacking in blood group antigens. On the contrary, the biliary cell was rich in antigenic markers: the main antigens expressed were Lewis, Pr, HLA-A and B antigens. In Kupffer cells, only i and HLA-DR antigens were clearly expressed. The endothelial cells of blood vessels mainly show A, B, H, HLA-A and B antigens; HLA-DR and Pr are slightly expressed. HLA-DR antigens were more strongly expressed on veins than on arteries. Dendritic cells have been identified in the portal space of human liver. They bore i and HLA-DR antigens.     

Effects of chloride and potassium channel blockers on apoptotic cell shrinkage and apoptosis in cortical neurons

K⁺ and Cl^– homeostasis have been implicated in cell volume regulation and apoptosis. We addressed the hypothesis that K⁺ and Cl^– efflux may contribute to apoptotic cell shrinkage and apoptotic death in cultured cortical neurons. CLC-2 and CLC-3 chloride channels were detected in cultured cortical neurons. The Cl^– channel blockers 4,4-diisothiocyanatostilbene-2,2-disulfonic acid (DIDS), 4-acetamido-4-isothiocyanatostilbene-2,2-disulfonic acid (SITS) and 5-nitro-2-(3-phenylpropylamino)-benzoic acid (NPPB) inhibited the outwardly rectifying Cl^– current, prevented apoptotic cell shrinkage, and mildly attenuated cell death induced by staurosporine, C₂-ceramide, or serum deprivation. Cl^– channel blockers, however, at concentrations that prevented cell shrinkage had no significant effects on caspase activation and/or DNA fragmentation. Cell death in the presence of a Cl^– channel blocker was still sensitive to blockade by the caspase inhibitor z-Val-Ala-Asp(OMe)-fluoromethyl ketone (z-VAD-fmk). Electron microscopy revealed that, although DIDS prevented apoptotic cell shrinkage, certain apoptotic ultrastructural alterations still took place in injured neurons. On the other hand, the K⁺ channel blocker tetraethylammonium (TEA), clofilium, or the caspase inhibitor z-VAD-fmk prevented cell shrinkage as well as caspase activation and/or DNA damage, and showed stronger neuroprotection against apoptotic alterations and cell death. The results indicate that neurons may undergo apoptotic process without cell shrinkage and imply distinct roles for Cl^– and K⁺ homeostasis in regulating different apoptotic events.     

Temporal profile of potassium channel dysfunction in cerebrovascular smooth muscle after experimental subarachnoid haemorrhage

The pathogenesis of cerebral vasospasm after subarachnoid haemorrhage (SAH) involves sustained contraction of arterial smooth muscle cells that is maximal 6–8 days after SAH. We reported that function of voltage-gated K⁺ (K_V) channels was significantly decreased during vasospasm 7 days after SAH in dogs. Since arterial constriction is regulated by membrane potential that in turn is determined predominately by K⁺ conductance, the compromised K⁺ channel dysfunction may cause vasospasm. Additional support for this hypothesis would be demonstration that K⁺ channel dysfunction is temporally coincident with vasospasm. To test this hypothesis, SAH was created using the double haemorrhage model in dogs and smooth muscle cells from the basilar artery, which develops vasospasm, were isolated 4 days (early vasospasm), 7 days (during vasospasm) and 21 days (after vasospasm) after SAH and studied using patch-clamp electrophysiology. We investigated the two main K⁺ channels (K_V and large-conductance voltage/Ca²⁺-activated (K_Ca) channels). Electrophysiologic function of K_Ca channels was preserved at all times after SAH. In contrast, function of K_V channels was significantly decreased at all times after SAH. The decrease in cell size and degree of K_V channel dysfunction was maximal 7 days after SAH. The results suggest that K_V channel dysfunction either only partially contributes to vasospasm after SAH or that compensatory mechanisms develop that lead to resolution of vasospasm before K_V channels recover their function.     

心肌炎患者高频心电图QRS波群的功率谱分析

本文选取６９名心肌炎患者，９４名正常人做为对照。依其年龄不同，共分６组：幼儿心肌炎组，正常幼儿组，学龄心肌炎组，正常学龄组，成人心肌炎组，正常成人组。分别对这６组的Ⅱ导、ａＶＦ导、Ｖ２导、Ｖ５导ＱＲＳ波群０－１０００Ｈｚ、８０－３００Ｈｚ、１００－１０００Ｈｚ３个频段的功率谱（用绝对能量表示）进行了分析。结果提示，不同年龄的心肌炎患者，其心电信号高频频段的能量变化规律不一致。     

系列高频成分节段在正常人中的分布

将１３４例正常人按年龄分为幼儿组、学龄组、青年组和中老年组，分别观察分析了系列高频成分节段的分布特点。其分布无年龄、性别差异（Ｐ＞０．０５），系列高频成分节段对急性病毒性心肌炎的诊断特异性为８２．４１％。各年龄组的特异性分别是幼儿组９０％、学龄组８３．３％、青年组７２．４１％。中老年组８２．０５％。     

A mouse model of galactose-induced cataracts

Galactokinase (GK; EC 2.7.1.6) is the first enzyme in the metabolism of galactose. In humans, GK deficiency results in congenital cataracts due to an accumulation of galactitol within the lens. In an attempt to make a galactosemic animal model, we cloned the mouse GK gene (Glk1) and disrupted it by gene targeting. As expected, galactose was very poorly metabolized in GK-deficient mice. In addition, both galactose and galactitol accumulated in tissues of GK-deficient mice. Surprisingly, the GK-deficient animals did not form cataracts even when fed a high galactose diet. However, the introduction of a human aldose reductase transgene into a GK-deficient background resulted in cataract formation within the first postnatal day. This mouse represents the first mouse model for congenital galactosemic cataract.     

Alternative therapy of Alzheimer's disease via supplementation with choline acetyltransferase

Much evidence indicates that the memory and cognitive deficits of patients with Alzheimer's disease are closely associated with dysfunction of central cholinergic system. The degree of reduction of choline acetyltransferase activity in cerebral cholinergic neurons is significantly correlated with the severity of dementia or cognitive impairments observed in Alzheimer's disease. Therefore, Alzheimer's disease may be slowed by supplementation of exogenous choline acetyltransferase. Here we show that choline acetyltransferase mediated by TAT protein transduction domain passes through the blood-brain barrier and enters the neurons in mice, increasing choline acetyltransferase and neurotransmitter acetylcholine contents. The recombination TAT-choline acetyltransferase fusion protein injected intravenously improves the memory and cognitive dysfunction in Alzheimer's disease model mice induced by amyloid-beta peptide. Our results imply a novel and potentially effective way for Alzheimer's disease therapy.     

Skeletal muscle sodium channel gating in mice deficient in myotonic dystrophy protein kinase

Myotonic dystrophy, a progressive autosomal dominant disorder, is associated with an expansion of a CTG repeat tract located in the 3'-untranslated region of a serine/threonine protein kinase, DMPK. DMPK modulates skeletal muscle Na channels in vitro, and thus we hypothesized that mice deficient in DMPK would have altered muscle Na channel gating. We measured macroscopic and single channel Na currents from cell-attached patches of skeletal myocytes from mice heterozygous (DMPK(+/-)) and homozygous (DMPK(-/-)) for DMPK loss. In DMPK(-/-) myocytes, Na current amplitude was reduced because of reduced channel number. Single channel recordings revealed Na channel reopenings, similar to the gating abnormality of human myotonic muscular dystrophy (DM), which resulted in a plateau of Na current. The gating abnormality deteriorated with increasing age. In DMPK(+/-) muscle there was reduced Na current amplitude and increased Na channel reopenings identical to those in DMPK(-/-) muscle. Thus, these mouse models of complete and partial DMPK deficiency reproduce the Na channel abnormality of the human disease, providing direct evidence that DMPK deficiency underlies the Na channel abnormality in DM.     

碱性成纤维细胞生长因子与卵巢癌的关系

目的　探讨碱性成纤维细胞生长因子 (basic fibroblast growth factor,b FGF)对卵巢癌细胞增殖、浸润和肿瘤血管生成的影响 ,及 b FGF单克隆抗体 (b FGF monoclonal antibody,b FGF- MAb)的治疗作用。　方法　将人卵巢癌细胞株 SKOV3接种于 2 4孔板 ,加入不同浓度的 b FGF,每日行结晶紫染色后测定光密度 (D4 90 )值 ,绘制细胞生长曲线 ;将 SKOV3细胞团接种于铺设有细胞外基质凝胶的 4孔板 ,每日测定癌细胞在凝胶中的浸润距离 ;建立 SKOV3细胞裸鼠皮下移植瘤模型 ,每周两次分别将 b FGF、b FGF-MAb和生理盐水注射于移植瘤周围 ,8周后测量肿瘤体积 ;对移植瘤组织切片行 因子的免疫组化染色、测定肿瘤内微血管密度 (microvessel density,MVD)。　结果　 b FGF能促进 SKOV3细胞增殖并呈浓度依赖 ,实验第 5天 ,5 ng/ml、10 ng/ml组细胞 D4 90 值是对照组的 1.0 9倍和 1.2 1倍 ;b FGF能促进 SKOV3细胞浸润并呈浓度依赖 (P<0 .0 5 ) ,第 7天 ,5 ng/ml、10 ng/ml组细胞浸润距离分别是对照组的 1.5 3倍和2 .4 5倍 ;b FGF组移植瘤体积和 MVD分别是对照组的 1.80倍和 1.4 6倍 (P<0 .0 5 ) ,b FGF- MAb组移植瘤体积和 MVD分别是对照组的 6 3.7%和 6 2 .8% (P<0 .0 5 )。　结论　b FGF能明显促进卵巢癌细胞的增殖、     

Morphometric evaluation of PGP9.5 and NCAM expressing nerve fibers in colonic muscle of patients with Hirschsprung's disease

A quantitative assessment of the density of the protein gene product 9.5 (PGP9.5), the neural cell adhesion molecule (NCAM), and the low-affinity nerve growth factor receptor (NGFR) expressing nerve fibers in the circular muscle layer in the colon was carried out by morphometric analyses from 13 patients with Hirschsprung's disease (HD). The difference in the nerve fiber density between the ganglionic and aganglionic segments was compared by calculating the ratio of the sum of the areas occupied by positively stained nerve fibers per unit area of the muscle after immunohistochemical staining on paraffin embedded tissue sections using computer software. There was an obvious difference in the density of the PGP9.5 stained nerve fibers between the ganglionic (0.0380 +/- 0.0171) and aganglionic segments (0.0143 +/- 0.01661). The NCAM-positive nerve fibers were fewer in number than those of both the PGP9.5-positive fibers and NCAM-positive fibers, which were also markedly lower in number in the aganglionic segment (0.0066 +/- 0.0076) than in the ganglionic segment (0.0230 +/- 0.0195). Immunostaining for low-affinity NGFR revealed much fainter staining in the ganglionic and aganglionic segment without a statistically significant difference in their density. Considering the fact that PGP9.5 is a very sensitive marker for nerve fibers, the results of this study reaffirm the innervation failure of the proper muscle in HD. The decreased NCAM expression level in the aganglionic segment appears to be caused not by the selective down-regulation of NCAM expression among the nerve fibers but by a markedly reduced number of nerve fibers.