Apolipoprotein D is down-regulated during malignant transformation of neurofibromas

Apolipoprotein D (apoD) expression was studied in nonneoplastic peripheral nerve, neurofibromas (NFs), and malignant peripheral nerve sheath tumors (MPNSTs) by quantitative polymerase chain reaction, in situ hybridization, and immunohistochemistry. Multiplex quantitative polymerase chain reaction for messenger RNA was performed on a series of formalin-fixed and paraffin-embedded specimens that included 9 MPNSTs, 12 NFs, and 4 normal peripheral nerves. The average apoD expression was 108-fold decreased (DeltaCt = -7.3) in the MPNSTs compared with the NFs (P < .05). ApoD expression levels were 3.0-fold elevated (DeltaCt = 1.7) in the NFs compared with nonneoplastic peripheral nerve (P < .05). In situ hybridization for apoD RNA was performed on a separate series of 10 cases in which each microscopic section included both MPNST and the NF from which it arose. These studies confirmed elevated apoD expression in NFs compared with MPNSTs and demonstrated that this expression was variable among individual cells within the NFs. Differential expression by immunohistochemistry could only be demonstrated in selected areas, most likely because apoD protein is a small molecule that is secreted out of the cell into the extracellular space and plasma. ApoD expression initially increases a small amount with the formation of NFs from nonneoplastic peripheral nerve and subsequently decreases markedly as NFs transform into MPNSTs. This expression pattern may serve as a marker for cell cycle inhibition during peripheral nerve tumorigenesis.     

Effect of aging on neuroglobin expression in rodent brain

Neuroglobin (Ngb), a recently discovered O2-binding heme protein related to hemoglobin and myoglobin, protects neurons from hypoxic-ischemic injury in vitro and in vivo. In immunostained mouse brain sections, we found widespread expression of Ngb protein in neurons, but not astrocytes, of several brain regions that are prominently involved in age-related neurodegenerative disorders. Western blots from young adult (3 month), middle-aged (12 month), and aged (24 month) rats showed an age-related decline in Ngb expression in cerebral neocortex, hippocampus, caudate-putamen, and cerebellum. Loss of this neuroprotective protein may have a role in increasing susceptibility to age-related neurological disorders.     

Human anti-JC virus serum reacts with native but not denatured JC virus major capsid protein VP1

The immunoreactivity of human anti-JC virus (JCV) serum against the major capsid protein VP1 of JCV was analyzed by Western blot, dot blot, and hemagglutination inhibition (HAI) assays. JCV-positive human serum reacted with native but not denatured JCV major capsid protein VP1, as demonstrated by dot blot and Western blot. Rabbit antiserum raised against native JCV capsid had immunoreactivities similar to those of human anti-JCV serum. These results indicate that the antigenecity of native and denatured JCV VP1 is different. In addition, both JCV-positive human serum and rabbit antiserum raised against native JCV capsid protein inhibited the hemagglutination activity of JCV capsid particles. In contrast, rabbit antiserum raised against denatured JCV VP1 did not inhibit hemagglutination. These findings reveal that denaturation may alter the antigenic epitopes of JCV VP1. Therefore, keeping the JCV capsid protein native appears to be essential for serological or other immunological analyses of the virus.     

Hereditary Cerebral Hemorrhage with Amyloidosis-Dutch Type (HCHWA-D): I - A Review of Clinical, Radiologic and Genetic Aspects

Hereditary cerebral hemorrhage with amyloidosis - Dutch type (HCHWA-D) is an autosomal dominant disease caused by deposition of β-amyloid in the leptomeningeal arteries and cortical arterioles, in addition to preamyloid deposits and amyloid plaques in the brain parenchyma.
The disease is due to a point mutation at codon 693 of the amyloid precursor protein (βPP) gene at chromosome 21. Since this point mutation is diagnostic for HCHWA-D, presymptomatic testing is feasible and offered, together with genetic counselling and psychological support, to subjects at risk. HCHWA-D is clinically characterized by recurrent strokes, in addition to dementia, which can occur after the first stroke but also preceding it. Radiological studies revealed focal lesions (hemorrhages, hemorrhagic and non-hemorrhagic infarctions) and diffuse white matter damage. Diffuse white matter hyperintensities on MRI are an early symptom of HCHWA-D since they have been found on MRI scans of subjects who had not suffered a stroke.
The presence of the diagnostic point mutation makes HCHWA-D a useful model to study the effects of cerebral amyloid angiopathy in vivo. The characteristic pathological abnormalities and its implications for Alzheimer's disease will be discussed in Part II of this article     

Cocaine or delta 9-tetrahydrocannabinol does not affect cellular cytotoxicity in vitro

Cocaine or delta 9-tetrahydrocannabinol (THC), the major psychoactive component of marijuana, has no effect on in vitro cytotoxicity mediated by natural killer (NK) cells and cytotoxic T-lymphocytes (CTL) at concentrations similar to those observed in vivo.     

国人男性椎管的测量与观察

本文对广西出土的113例男性干燥椎骨的椎孔,进行了矢径、横径的测量和形态观察。椎孔的矢、横径在壮族(30例),汉族(57例)间无显著差异(P>0.05)。在C_(3～6)椎骨水平,推管的矢径和形态与脊髓的外形不一致,矢径于该处形成生理性狭窄,以C_4处为最小(12.92mm)。除C_1外,椎管的形态可分为4型:Ⅰ型圆型;Ⅱ型三角型;Ⅲ型过渡型;Ⅳ型不整型。 C_(1,2)椎管的形状为圆型,向下至C_6,通过半圆形逐步过渡到三角形(C_6占81.31％);再向下至T_6,三角形通过蛤形和多边形又逐渐过渡为圆形(T_6占84.76％);再向下至L_5,又通过蛤形逐渐过渡为三角型(L_5占99％)。从L_3至L_5,三角形椎孔有逐步通过钟形向三叶形过渡的趋势。三叶形腰椎管占5.02％。本文结果支持Eisenstein的观点,认为三叶形结构是一种普通的、非病理性的现象,与年龄增长、骨赘或椎孔狭窄无关,这或许是一种正常的发育性变异。     

试论医德的规范化建设

随着社会主义市场经济体制改革的逐步深入,人们的思想观念发生新的矛盾和冲突。为此,必须进一步进行医德的规范化建设,通过教育、管理、法律一体化建设,使医德达到医心赤诚、医术精湛、医纪严肃、医风正派、医行端正、合作精诚的规范化标准。     

腭裂儿童ABR表现的初步研究

目的探索腭裂儿童听力受损情况及其听性脑干反应(ABR)异常特征。方法对94例腭裂儿童进行ABR测试,并与正常对照组进行比较。结果94例患儿(188耳)中,不同程度的听力下降共150耳。患儿左耳ABR波Ⅰ、Ⅲ、Ⅴ的峰潜伏期(PL)分别为2.14±0.38、4.30±0.41、6.20±0.53ms;右耳分别为2.12±0.39、4.29±0.44、6.21±0.53。对照组左耳波Ⅰ、Ⅲ、Ⅴ的峰潜伏期分别为1.50±0.13、3.74±0.12、5.60±0.15ms;右耳分别为1.60±0.16、3.72±0.13、5.62±0.17ms。上述所有数据,患儿组与对照组比较,差异均有显著性(P<0.05)。＜3岁的28例听力下降的发生率为94.6%(53/56耳),中重度异常占66.7%;3～6岁的发生率为77.0%(57/74耳),6岁以上至12岁的发生率为69.0%(40/58耳),3岁以后听力中重度异常仅占33.3%。结论腭裂组听力下降发生率高达79.8%;其ABR的特点为波Ⅰ、Ⅲ、Ⅴ波的峰潜伏期均延长;腭裂组年龄越小的,听力损害发生率越高,听力损害程度越重。