Chromosome changes in Alzheimer''s presenile dementia.

Lymphocyte chromosomes were examined in 36 patients with Alzheimer's presenile dementia, 36 healthy, age and sex matched controls, and 36 sex matched, non-demented, elderly controls, approximately 20 years older than the Alzheimer patients. Increased chromosome aneuploidy was found in females with Alzheimer's disease but not in male subjects. Chromosome abnormalities observed in female patients were similar to those observed in elderly controls, though in this latter group there was an increase in the frequency of cells that had lost an X chromosome. In the female Alzheimer patients and the elderly controls, there was an increase in the frequency of autosomal aneuploid cells but no single chromosome was preferentially affected. Because the chromosome abnormalities found in Alzheimer's disease are similar in nature but not as extensive as those observed in senescence in the absence of dementia, it is argued that chromosome aneuploidy is more likely to be related to processes concerned with ageing rather than being specifically linked to the dementia of Alzheimer's disease.     

Characteristics of Epstein-Barr virus transformed B cell lines from patients with Alzheimer's disease and age-matched controls.

The characteristics of B cell lines isolated from patients with Alzheimer's disease (AD) and age-matched controls were investigated after having been transformed by Epstein-Barr virus (EBV). After isolation of mononuclear blood cells and in vivo or in vitro EBV infection, 35 and 21 lymphoblastoid cell lines (LCLs) were generated from 19 patients with AD (mean age 79.4 years) and 21 age-matched controls (mean age 80.0 years), respectively. B lymphocytes from AD patients were immortalised more easily than those from controls; the percentage of in vitro EBV infected LCLs (B95-LCLs) obtained in the AD group was significantly higher (76.2% versus 33.3% in the control group) and the mean time required for establishment was significantly lower (20.2 and 21.9 days versus 26.7 and 60.9 days in the control group). The EBV receptor and surface immunoglobulin (Ig) analyses showed no difference between the two groups. The expression of Epstein-Barr early antigens (EA) and viral capsid antigens (VCAs) revealed a tendency to higher viral replication in LCLs from AD patients; however, VCA expression remained limited to a small number of cells and did not affect overall cell growth. Finally, qualitative and quantitative differences were observed in the pattern of Ig production. Whereas spontaneously established LCLs from AD patients were generally monoclonal (80% of LCLs versus 33% in the control group), B95-LCLs were all polyclonal and secreted more IgM and IgA than those from controls; the mean IgM level was significantly higher in B95-LCLs from the AD group. These results suggest that B cells derived from AD patients seemed to be less differentiated than cells from age-matched controls.     

Immunoglobulin and other proteins in the cerebrospinal fluid of patients with Alzheimer''s disease.

Immunoglobulin has been measured and studied electrophoretically in cerebrospinal fluid (CSF) from 14 patients with Alzheimer's disease and 25 undemented controls. Presence or absence of the diagnosis of Alzheimer's disease was confirmed histologically, as these were postmortem specimens. There was no increased incidence of oligoclonal IgG bands in either group, and no significant differences in the levels of IgG and albumin. Non-immunoglobulin bands were found in the gamma region in some samples from Alzheimer's disease patients and controls; such bands are not found in the CSF from younger patients. There was a significantly increased incidence of double transferrin and double tau protein bands in the Alzheimer's group, suggesting that further studies of genetic markers might be worthwhile.     

Immunologic dysfunction: simultaneous study of Alzheimer's and older Down's patients

Peripheral blood lymphocytes from Alzheimer's disease patients, older patients (aged 25-59 years) with Down's syndrome and closely age-matched healthy controls were tested in vitro for DNA synthesis in response to stimulation by phytohemagglutinin, pokeweed mitogen and OKT3 monoclonal antibody to T3 antigen. All were significantly decreased in Down's and Alzheimer's patients relative to healthy controls. The autologous mixed lymphocyte reaction (AMLR), unstimulated or stimulated with anti-T3. in the 2 patient groups did not differ significantly from the healthy controls. We also quantified the proportions of the T cells staining positive for surface membrane orosomucoid, and found their levels to be either higher or lower than normal in Down's patients, but not in Alzheimer's patients. These results demonstrate the existence of defective cellular immune functions in both elderly Down's patients and Alzheimer's patients.     

Human red blood cell choline uptake with age and Alzheimer's disease

Since previous studies suggested that blood choline homeostasis is altered in aging and in Alzheimer's disease, choline uptake was examined in human red blood cells (RBC) from young adults, intellectually-intact elderly controls and outpatients with Alzheimer's disease. Eadie-Hofstee analysis of uptake by RBC from young controls indicated two components; thus, group comparisons were done with 1 and 50 microM choline in the media. Temperature-dependent choline uptake at low and high choline concentrations increased in RBC from elderly controls (62-66%) or Alzheimer patients (52-54%) compared to young controls. These changes in transport were not directly related to altered RBC choline content, since RBC choline concentrations did not vary significantly between groups. However, plasma choline content was significantly elevated in elderly controls and Alzheimer patients compared to young control values. The RBC to plasma ratio of choline was reduced in elderly compared to young controls, whereas the ratio in Alzheimer patients was between the two other groups. Thus, abnormalities in RBC choline uptake and plasma choline content were not exacerbated in Alzheimer patients, and these results do not support suggestions that Alzheimer's disease is a form of generalized accelerated aging. The striking changes in RBC choline uptake and plasma choline content in elderly subjects do indicate age-related changes in systemic choline homeostasis and these abnormalities may contribute to the predisposition of the elderly to neurological diseases.     

An HLA and family study of Alzheimer's disease

Histocompatibility antigens were examined in 124 patients with Alzheimer's disease (AD), and the frequency of HLA-B15 was found to be significantly increased over controls. Pooling of data from the present and similar studies suggests that AD is not strongly associated with any particular HLA antigen, although there may be a weak association with HLA-A2, B15 and Cw3. In a family study of 34 patients with AD, secondary cases of AD were identified in 9.7% of the first-degree relatives, and cases of presenile dementia and senile dementia of the Alzheimer type were found to occur within individual families.     

Chromosome aneuploidy in Alzheimer''s disease

We present cytogenetic findings in 9 patients with Alzheimer's disease (AD) and 35 normal age matched controls. The study was undertaken due to reports of increased aneuploidy in individuals with AD. Coded peripheral blood chromosome preparations were evaluated for aneuploidy; there were 4.5% hypomodal cells in AD patients compared with 5.5% in controls. There were no hypermodal cells in the AD group and only 0.7% among the controls. Statistical analyses of the results did not show any differences between AD patients and controls in these data. There was a statistically significant increase in the loss of C group chromosomes in the old controls which we attribute to ageing.     

HLA, blood groups and secretor status in patients with established rheumatic fever and rheumatic heart disease

The distribution of HLA-A, -B and -DR antigens as well as blood groups and secretor status was studied in sporadic, North Indian patients of rheumatic fever and rheumatic heart disease. While HLA-Aw33 occurred with an increased frequency in the patient group (X2 = 4.01), no statistically significant differences were observed in the frequency of B-locus antigens. In the DR locus, HLA-DR3 was found to be significantly increased (50% vs 26.1%, X2 = 13.8) and DR2 significantly reduced (21.8% vs 47.0%, X2 = 15.6). Also, there was a preponderance of non-'O' blood group individuals in the patient group as compared to controls. The DR3 association was significant only in those patients of RHD who did not have any previous history of rheumatic fever. These results indicate that susceptibility to rheumatic heart disease is HLA-class II mediated, with HLA-DR3 influencing susceptibility and DR2 conferring protection.     

Alzheimer病患者早老素-1基因第5外显子突变特征分析

目的　探讨早老素-1 基因突变在散发性Alzheim er 病(sporadic Alzheim er's disease, SAD)患者发病机理中的作用。方法　应用聚合酶链反应-单链构象多态性(polym erase chain reaction-singlestrand conform ation polym orphsim ,PCR-SSCP)及DNA 直接测序技术检测68 例SAD 患者和65 名正常老年人的早老素-1 基因第5 外显子。结果　发现68 例SAD患者中有4 例患者的SSCP发生泳动异常,DNA 序列分析发现:这4 例SAD 患者的130 号密码子发生了CTG→ATG 错义突变(388 位点发生C→A突变),使氨基酸由亮氨酸变为蛋氨酸(Leu 130 Met);157 号密码子发生了GTG→CTG 错义突变(469 位点发生G→C突变),使氨基酸由缬氨酸变为亮氨酸(Val157 Leu);有11 例患者的SSCP表现为一条单链电泳迁移率明显增快,DNA 序列分析发现:这11 例SAD患者的130 号密码子发生了CTG→ATG 错义突变(388 位点发生C→A 突变),使氨基酸由亮氨酸变为蛋氨酸(Leu 130 Met);154 号密码子发生了TGC→TGT 同义突变(462 位点发生C→T)突变。结论　我们发现在SAD患者中存在早老素-1 基因第5 外显子突变,该突变点可能为中国人SAD 患者早老素基因突变点之一。     

The effect of increased concentrations of homocysteine on the concentration of (E)-4-hydroxy-2-nonenal in the plasma and cerebrospinal fluid of patients with Alzheimer's disease

There is evidence that increased blood concentrations of homocysteine may be a risk factor for Alzheimer's disease. (E)-4-hydroxy-2-nonenal (HNE) is a neurotoxic product of lipid peroxidation that is increased in the ventricular fluid and brains of patients with Alzheimer's disease. We measured the concentrations of homocysteine, HNE, vitamin B(12) and folate in the plasma of 27 patients with Alzheimer's disease and 25 control subjects. There was a statistically significant increase in the plasma concentration of homocysteine (P < 0.001) and HNE (P < 0.001) in the Alzheimer's disease patients compared to the control group. There was a significant decrease in the plasma concentration of vitamin B(12) (P < 0.001) and folate (P = 0.002) in the Alzheimer's group compared to the controls. There was a significant positive correlation between the plasma concentrations of homocysteine and HNE in the patients with Alzheimer's disease (r = 0.661, P < 0.001). A significant negative correlation was found between the plasma concentration of homocysteine and the plasma concentrations of vitamin B(12) (r = -0.605, P = 0.0006) and folate (r = 0.586, P = 0.001). We also measured the concentrations of homocysteine, HNE, vitamin B(12) and folate in the cerebrospinal fluid (CSF) of 8 patients with Alzheimer's disease compared to 6 control subjects. The concentrations of homocysteine (P = 0.032) and HNE (P = 0.001) were significantly higher in the CSF of Alzheimer's patients than in the control subjects. There were significant positive correlations between the CSF concentrations of homocysteine and HNE (r = 0.924, P = 0.001). There was also a significant positive correlation between the plasma concentration of homocysteine and the CSF concentrations of homocysteine (r = 0.850, P = 0.007) and HNE (r = 0.092, P = 0.002). These results demonstrate that there is a relationship between increased homocysteine concentrations and increased HNE concentrations in Alzheimer's disease.     

Search for DNA alterations in Alzheimer's disease

The DNA of brain cortex obtained from autopsy specimens of eight patients with Alzheimer's disease and eight controls was examined for content of normal and abnormal bases. DNA, purified by hydroxyapatite chromatography, was hydrolyzed under mild conditions and the deoxynucleosides were measured by high performance liquid chromatography (HPLC). No differences in the mole percentages of deoxynucleosides in DNA were detected in patients with Alzheimer's disease compared to controls, nor were abnormal deoxynucleosides found. Restriction-nuclease digests examined by agarose gel electrophoresis also showed no changes. Thus, diffuse and persistent damage to the DNA in brain in Alzheimer's disease was not detected by these methods.     

Alzheimer's disease: is the decrease of the cholinergic innervation of the hippocampus related to intrinsic hippocampal pathology?

Consistent findings in the hippocampi of patients with Alzheimer's disease are the presence of neurofibrillary tangles in pyramidal neurons and the loss of choline acetyltransferase activity due to degeneration of hippocampal cholinergic terminals. The present study sought to clarify, in the brains of five patients with Alzheimer's disease and four controls, whether the loss of cholinergic terminals in the hippocampal stratum pyramidale in Alzheimer's disease is related to degenerative changes in hippocampal pyramidal cells. A polyclonal antibody to human choline acetyltransferase was employed to visualize immunohistochemically cholinergic terminals. Hippocampal neurons were stained with Cresyl Violet, neurofibrillary tangles with thioflavin S and a monoclonal antibody against phosphorylated neurofilament (RT97). Quantification of the stained structures was performed in CA4, CA1 and the subiculum, on five sections selected from the entire anteroposterior extent of each hippocampus. In the group of Alzheimer patients, the densities of cholinergic terminals were homogeneously diminished in the three hippocampal subregions in comparison with the controls (32-33%). In contrast, a significant loss of pyramidal neurons was found only in CA1, and the density of neurofibrillary tangles was markedly increased only in CA1 and the subiculum in Alzheimer's disease. These findings suggest that there is no relationship between the loss of cholinergic terminals and the degeneration of pyramidal cells in the hippocampus of patients with Alzheimer's disease.     

T lymphocyte responses to anti-neutrophil cytoplasmic autoantibody (ANCA) antigens are present in patients with ANCA-associated systemic vasculitis and persist during disease remission

ANCA with specificity for myeloperoxidase (MPO) and proteinase 3 (PR3) are present in patients with systemic vasculitis. The aim of this work was to determine whether such patients have T cell responses to these antigens and whether these responses are related to disease activity. Peripheral blood lymphocytes from 45 patients and 19 controls were cultured with ANCA antigens and proliferation measured. The antigens used were heat-inactivated (HI) MPO, HI PR3, native (non-HI) PR3, HI whole α-granules, and 25 overlapping peptides covering the entire PR3 sequence. Significant responses to both whole PR3 preparations were seen from patient and control groups, and to the α-granules from the patient group. Patients responded at all stages of disease: active, remitting, treated or untreated. Only two patients responded significantly to MPO. Responses were significantly higher with the patient group than the control group to all four whole ANCA antigens. Responses to those PR3 peptides containing epitopes known to be recognized by ANCA were detected from one patient. Thus, these studies demonstrate that T cells from vasculitis patients can proliferate to PR3 and occasionally to associated ANCA antigens. Further, responses may persist even after disease remission has been achieved.     

Sarcoidosis: correlation of delayed hypersensitivity, MLC reactivity and lymphocytotoxicity with disease activity

Delayed skin reactivity to a battery of antigens was assessed for a series of sarcoidosis patients and closely matched controls. It was compared with the proliferative and cytotoxic capacity of corresponding blood lymphocyte preparations after challenge in mixed lymphocyte culture with an allogeneic lymphoma cell line.

Skin anergy to all antigens tested was found only within the patient group having definitely active disease. These patients also showed depression of lymphocyte proliferative response in the in vitro test system as compared to matched controls and to patients with apparently inactive disease. Both of these differences were statistically significant. Skin reactivity to tuberculin was significantly depressed for the whole sarcoidosis group (both active and inactive) as compared to the control group and significant impairment of capacity to develop cytotoxicity in vitro was also found in comparison of these same groups.

The results obtained confirm the association of impaired delayed skin hypersensitivity in sarcoidosis with diminished lymphocyte reactivity in vitro, especially when the disease is active. The reduced cytotoxic capacity of sarcoid lymphocytes in vitro may reflect a comparable in vivo impairment and partly explain the depressed skin tests and also contribute to the protracted nature of the disease because of failure to eradicate the postulated `sarcoid agent'.

     

Optic-nerve degeneration in Alzheimer's disease

Alzheimer's disease is a dementing disorder of unknown cause in which there is degeneration of neuronal subpopulations in the central nervous system. In postmortem studies, we found widespread axonal degeneration in the optic nerves of 8 of 10 patients with Alzheimer's disease. The retinas of four of the patients were also examined histologically, and three had a reduction in the number of ganglion cells and in the thickness of the nerve-fiber layer. There was no retinal neurofibrillary degeneration or amyloid angiopathy, which are typically seen in the brains of patients with Alzheimer's disease. The changes we observed in the patients with Alzheimer's disease were clearly distinguishable from the findings in 10 age-matched controls and represent a sensory-system degeneration that occurs in Alzheimer's disease. Study of the retina in patients with this disease may be helpful diagnostically, and isolation of the affected ganglion cells may facilitate molecular analysis of the disorder.     

Genetic association of an alpha2-macroglobulin (Val1000lle) polymorphism and Alzheimer's disease

alpha2-Macroglobulin (A2M) is a proteinase inhibitor found in association with senile plaques (SP) in Alzheimer's disease (AD). A2M has been implicated biochemically in binding and degradation of the amyloid beta (Abeta) protein which accumulates in SP. We studied the relationship between Alzheimer's disease and a common A2M polymorphism, Val1000 (GTC)/Ile1000 (ATC), which occurs near the thiolester active site of the molecule. In an initial exploratory data set (90 controls and 171 Alzheimer's disease) we noted an increased frequency of the G/G genotype from 0.07 to 0.12. We therefore tested the hypothesis that the G/G genotype is over-represented in Alzheimer's disease in an additional independent data set: a group of 359 controls and 566 Alzheimer's disease patients. In the hypothesis testing cohort, the G/G genotype increased from 0.07 in controls to 0.12 in Alzheimer's disease (P < 0.05, Fisher's exact test). The odds ratio for Alzheimer's disease associated with the G/G genotype was 1.77 (1.16-2.70, P < 0.01) and in combination with APOE4 was 9.68 (95% CI 3.91-24.0, P < 0.001). The presence of the G allele was associated with an increase in Abeta burden in a small series. The A2M receptor, A2M-r/LRP, is a multifunctional receptor whose ligands include apolipoprotein E and the amyloid precursor protein. These four proteins have each been genetically linked to Alzheimer's disease, suggesting that they may participate in a common disease pathway.      

Unbiased whole-brain analysis of gray matter loss in Alzheimer's disease

In patients with Alzheimer's disease, substantial tissue loss occurs in the medial temporal lobe. In this study, we applied a voxel-based, unbiased whole-brain analysis method to compare magnetic resonance imaging scans of seven patients with Alzheimer's disease and seven healthy elderly controls. Images were transformed to standard coordinate space and tested for gray matter loss in patients. We found symmetrical decreases of gray matter in patients in the hippocampus, and, unexpectedly, also in the head of the caudate nucleus and the insula. The exact role of these two structures in the symptomatology of Alzheimer's disease deserves further attention.     

血型基因检测对照品的制备及其在三种稀有血型筛选中的应用

目的 应用基于聚合酶链反应(polymerase chain reaction,PCR)的基因定点诱变技术(sitedirected mutagenesis,SDM)制备s、Oka血型等位基因检测对照品.用多重聚合酶链反应(multiplex PCR)技术建立3种血型Fy2、s和Ok2的基因分型方法,以了解这3种血型在中国随机献血者中的多态性分布状况.方法 采用基于PCR的基因定点诱变技术对s和Oka血型等位基因的单核苷酸多态性(single nucleotide polymorphism,SNP)位点构建了含有突变SNP位点(GYPB基因cDNA 153位C/T突变和BSG基因cDNA 274位G/A突变)的标准质粒,作为s和Oka血型等位基因检测的对照品.同时针对血型抗原Fya、s和Oka等位基因的SNP位点设计序列特异性(sequence specific primer,SSP)引物,构建多重PCR体系,对438份随机献血者样本进行Fya、s和Oka血型抗原的基因筛选.结果 成功应用定点诱变技术完成了s和Oka基因检测中等位基因对照品的制备,并建立了可同时检测Fya、s和Oka血型的多重PCR体系,438份随机献血者样本中共检出2例Fy(a-)样本,未检出s-和Ok(a-)样本.结论 基于PCR的基因定点诱变技术能够得到难以获得的血型基因检测等位基因对照品,用于验证基因分型方法.本实验建立的多重PCR体系是一种有效的进行Fya、s和Oka血型基因检测的方法.     

HLA antigens and Graves' disease in Black South Africans

This study concerns the frequencies with which 36 HLA-A, -B and -C antigens occurred in 84 Black Africans with Graves' disease and in 311 Black controls. In the hyperthyroid patients significant reductions were found in the frequencies of HLA-B7 ( P <0.001, relative risk (RR) 0.33), HLA-Bw42 ( P <0.001, RR 0.32) and the HLA-B7-Bw42 crossreactive group (CREG) ( P <0.0001, RR 0.27), and in the frequencies of the phenotypic combinations HLA-A1, B7 ( P <0.001) and Aw30, B7-Bw42 ( P <0.001). HLA-B8 was increased in frequency ( P <0.01, RR 2.84). In patients without circulating antithyroglobulin or antimitichondrial antibodies the frequencies of HLA-A2 and B17 were increased when compared to those with antibodies or to the controls. In patients with and without clinically evident infiltrative ophthalmopathy the frequencies of HLA antigens were similar. In 62 Caucasian patients with Graves' disease, no antigens or phenotypic combinations occurred with increased or decreased frequency when compared to 278 controls.
Analysis of the frequencies of 9 HLA antigens and phenotypic combinations common in Caucasians but rare in Blacks revealed that only two antigens (A2 and B8) occurred with increased frequency in Black patients, suggesting that a contribution of Caucasian genes to the Black thyrotoxic subjects was unlikely.
Similarly, only one common Black antigen (A28) of 8 common antigens and phenotypic combinations, occurred in Caucasian patients with a frequency similar to that of Black controls. Thus it is unlikely that Black genes contributed to the lack of a significant increase of HLA antigens in the Caucasian thyrotoxic patients. The possession of HLA-B7-Bw42 CREG or related genes may be a protection against Graves' disease in Black Africans.     

过磷酸化tau蛋白在阿尔茨海默病患者脊髓中的表达

目的 观察过磷酸化tau蛋白在阿尔茨海默病(AD)患者脊髓中的表达及其在AD发病中的可能机制.方法 常规取神经病理证实的3例AD患者脊髓和7例老龄非痴呆性且无重要神经系统疾病对照患者脊髓,胸2、胸8、胸10、腰4和骶2平面取材.常规制片,行Gallyas-Braak染色及过磷酸化tau蛋白(AT8)免疫组织化学染色(SP法),光镜观察过磷酸化tau蛋白在AD及各对照组脊髓的分布情况.结果 3例AD患者中2例在脊髓前角出现过磷酸化tau蛋白阳性神经元,3例出现过磷酸化tau蛋白阳性轴索或轴索样结构,3例出现胶质细胞内过磷酸化tau蛋白表达,过磷酸化tau蛋白阳性程度与脑内神经原纤维缠结程度相关;对照组中仅1例脊髓胸2平面可见过磷酸化tau蛋白阳性的点状结构.结论 过磷酸化tau蛋白可以在AD患者脊髓内表达,提示轴浆运输障碍可能在AD的发病机制中具有一定作用.

Abstract：

Objective To study the expression of tau-related protein in spinal cord of Chinese patients with Alzheimer's disease. Methods Gallays-Braak stain and immunohistochemical study for tau protein (AT8) were carried out in the spinal cord tissue (T2, T8, T10, L2 and S2 segments) of 3 Chinese patients with Alzheimer's disease. Seven age-matched cases without evidence of dementia or neurologic disease were used as controls. Results Neurofibrillary tangles were identified in the neurons of anterior horn in 2 Alzheimer's disease cases but none was observed in the controls. Tau-positive axons and astroglia were detected in all Alzheimer's disease cases. Tau immunoreactivity in spinal cord of the patients correlated with that in brain tissue. Conclusion The expression of tau-related protein is demonstrated in the spinal cord of Alzheimer's disease patients suggesting that axonal transport defect may play a role in the pathogenesis of Alzheimer's disease.