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41.
Senile plaques in Alzheimer's disease (AD) are composed principally of Aβ, a 4 kDa fragment of the amyloid precursor protein (APP). Longer forms of APP which contain a Kunitz proteinase inhibitor (KPI) domain are elevated in aged and in AD brains. Tissue factor pathway inhibitor-1 (TFPI) contains three tandem KPI domains and has been well characterized for its role as a natural anticoagulant in the extrinsic coagulation pathway. Functionally, the first two KPI domains of TFPI bind and inhibit the activity of factor Xa and VIIa respectively. In addition, TFPI and APP-KPI share a common clearance mechanism through the low density lipoprotein receptor-related protein (LRP). As part of an ongoing study of the role of KPI-containing proteins in AD, the current study examines TFPI localization in the brain. We report here that TFPI is immunohistochemically localized to microglia in both AD and non-AD individuals and is localized to some senile plaques in AD. Western blot analyses indicate that the amount of TFPI is elevated in frontal cortex samples from AD brains. We propose that TFPI may play a cell specific role in proteinase regulation in the brain. 相似文献
42.
在1989年乌鲁木齐市进行的脐带血筛选中,我室又发现了一例异常胎儿血红蛋白(HbF)。理化性质测定证明该变异体为一轻度不稳定Hb。经反相高效液相色谱法(HPLC)等方法测定证明该变异体为HbF-新疆[~Aγ~T25(B7)Gly→Arg]。胡怀钰曾于1986年首次发现该变异体,并命名。与前例比较,本例除分析方法部分不同外,两例先证者的临床症状亦稍有差别。本例的先证者在半岁前患有轻度贫血,而首例先证者未见关于贫血的报道。 相似文献
43.
Summary The sensitivities of six silver-staining methods and immunohistology for beta and tau protein were compared for their ability to demonstrate neurofibrillary tangles (NFT) and senile plaques (SP) in paraffin sections. Serial sections of the hippocampal area of 35 brains showing these neuropathological findings were cut and stained by the methods of Cross, Campbell, Bielschowsky, Gallyas, Yamaguchi, our variant (method of Reusche) and immunohistology. In the detection of NFT, the techniques of Gallyas, Bielschowsky, our method and tau protein immunostaining were the most sensitive methods. The procedure of Campbell and again our method were proven to be superior to the other stainings in demonstrating SP as well as diffuse and subpial amyloid. Moreover, our method reliably stained vascular and perivascular amyloid which can be identified in brains with congophilic angiopathy. Due to a lack of control in certain steps of the procedures most of the silver-staining methods are complicated and to not present reliable results. Our variant is easy to perform and, thus, may be used as a sensitive, simple and reliable alternative for the impregnation of the main lesions (NFT and SP) occurring in senile dementia of Alzheimer type and brains with normal aging for screening, retrospective and quantitative studies and for routine purposes.Parts of this paper were presented at the IV. European Meeting of Neuropathology, Berlin Germany, 1992 相似文献
44.
Abstract – This study describes the early microbial colomization of teeth by the use of light-and transmission electron microscopy. Six dental students carried a total of 60 test pieces of unerupted enamel and root surface in intraoral acrylic appliances for 4, 8, 12, 24 and 48 h, during which periods oral hygiene was abandoned. Pronounced variations were recorded in structure and thickness of the pellicle across the individual surfaces of both dental tissues. Bacterial single-cell colonization increased the electron density of the adjoining pellicle. Micro-colonies of bacteria were observed in relation to enamel surface irregularities such as perikymata, while the distribution on root surfaces appeared incidental. Root surfaces were generally colonized by thicker deposits than homologous enamel surfaces although the structural composition of the microbiota was similar. Gram-positive bacteria with thick cell walls appeared in coccoid or rod-shaped configurations depending on the age of the bacterial deposit. These bacteria were further characterized by selective invasion between collagen fibers. After 48 h the complexity of the microbiota was increased by the establishment of new bacterial species in the superficial layer. It is concluded that the pattern and composition of the early microbiota on teeth is more complex and variable than hitherto assumed. 相似文献
45.
O. Bertel G. Noll 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》1988,2(1):107-111
Summary In a prospective single-blind study we examined the effects of additional molsidomine in 20 patients (63±10 years; 15 males, 5 females) with unstable resting angina (3 attacks/24 hours) refractory to triple therapy (nitrates, calcium antagonists, and beta blockers) combined with heparin or aspirin. All but one patient had coronary artery disease documented by coronarography (n=17) or by recent myocardial infarction (n=3). Two patients had angiographically documented severe coronary spasms. Patients entered the study if coronary bypass surgery or PTCA could not be performed within 3 days after angiography (n=9) or was not feasible due to anatomical or technical reasons (n=6), concomitant malignant disease (n=2), or age greater than 75 years (n=3). All patients received molsidomine orally 12 to 24 mg/day. In 15 of the 20 patients molsidomine was given i.v. initially, starting with 20 mg i.v., followed by infusion of 1 to 4 mg/hour. Heart rate and blood pressure did not change significantly, and eight patients had a slight decrease of systolic and diastolic blood pressure. Severe adverse effects did not occur, and moderate headaches were reported by five patients. In 13 patients, unstable angina could be stabilized, and they remained free of resting angina; five had a marked reduction of the frequency of anginal attacks. In two patients, molsidomine was without demonstrable beneficial effects. After a follow-up of 4 weeks, nine patients were free of symptoms after bypass surgery or PTCA, 10 continued to have angina NYHA class II or III, and one patient died due to acute myocardial infarction and cardiogenic shock 4 days after starting additional molsidomine. We conclude that molsidomine is well tolerated and has a marked beneficial effect in patients with refractory unstable angina. Molsidomine should therefore be considered for routine therapy of unstable angina, especially in those patients who are suspected of tolerance to nitrate therapy. 相似文献
46.
目的: 评价各种类型急性冠脉综合症 (ACS) 病人补体激活的情况和补体激活与心肌损伤的关系。方法: 研究对象分为ACS组110例和正常对照组18人。 ACS组包括ST段抬高型心肌梗死(STEMI)51例,非ST段抬高型心肌梗死(NSTEMI)28例和不稳定性心绞痛(UA)31人。检测病人和正常对照健康人血浆C3和C4,CK-MB和肌钙蛋白T (TnT)浓度。结果: STEMI和 NSTEMI病人峰值C3 水平[分别为(1 525±302) mg/L和(1 516±289)mg/L] 和C4[分别为(423±123) mg/L和(396±68) mg/L]水平高于UA病人和对照组的C3[分别为(1 275±172) mg/L和(1 072±196) mg/L,P<0.01] 和C4[分别为(356±91)mg/L和(182±73) mg/L,P<0.01]。UA病人的 C3 [(1 275±172) mg/L]和C4 [(356±91) mg/L]均高于对照组(P<0.01)。 ACS病人C3和C4水平在住院的前7 d均有明显的变化(P<0.01)。ACS病人峰值C3和C4水平与峰值CK-MB(分别为r=0.51和r=0.46,P<0.01)和肌钙蛋白T(分别为r=0.48和r=0.39,P<0.01)呈正相关。结论: ACS病人血浆C3和C4均明显升高。C3和C4水平与ACS的联系提示补体激活与心肌坏死有关。 相似文献
47.
Senri Kato Toshikazu Gondo Yoshinobu Hoshii Mutsuo Takahashi Michio Yamada Tokuhiro Ishihara 《Pathology international》1998,48(5):332-340
Senile plaques In the brains of Alzheimer's disease (AD) were examined by confocal laser scanning microscopy (CLSM) with the following three findings. First, in sections stained with Congo red, the serial CLSM images of optical sections clearly revealed that a classic plaque is composed of a plaque core and a corona. Radially arranged process-like structures, corresponding to bundles of amyloid fibrils, formed amyloid cores and stronger signals were detected in the center of some cores. Second, in sections stained with Congo red and anti-gllal fibrillary acidic protein (GFAP), reactive astrocytes were found around the senile plaques and many astrocytlc processes surrounded the plaque cores and some processes had penetrated into them. Third, three-dimensional reconstruction on classic plaque revealed that the surface of classic plaque showed a 'coral-like' appearance. 相似文献
48.
Direct molecular diagnosis of myotonic dystrophy 总被引:2,自引:0,他引:2
B. K. Hecht A. Donnelly A. K. Gedeon R. W. Byard E. A. Haan J. G. Mulley 《Clinical genetics》1993,43(6):276-285
Hecht BK, Donnelly A, Gedeon AK, Byard RW, Haan EA, Mulley JC. Direct molecular diagnosis of myotonic dystrophy. Clin Genet 1993: 43: 276–285. © Munksgaard, 1993 Myotonic dystrophy (DM) arises from an unstable trinucleotide (CTGn) repeat sequence within the DM locus at 19q13.3. Twenty-three myotonic dystrophy families containing 205 persons with no symptoms, minimal manifestations, classic DM or congenital DM were investigated to validate the application of the pM10M6 probe to direct molecular diagnosis. Affected family members had been diagnosed clinically and the unaffected family members had been assigned carrier probabilities close to either zero or 100%, using closely linked flanking markers. Southern analysis identified all 89 DM gene carriers as having expansions of the unstable element. PstI detected all small expansions of the repeat sequence as easily seen discrete bands; but large expansions were usually seen as diffuse smears, sometimes difficult to distinguish from lane background. EcoRI concentrated these diffuse smears, associated with somatic instability, into discrete bands which were easy to detect; but it did not resolve the smaller expansions present in 9 (10%) of the DM carriers. It is essential that PstI and EcoRI gels are run in parallel to detect all DM gene carriers. The extent of expansion of CTG correlated with age of onset and disease severity. Biopsies of various fetal tissues from two terminated pregnancies confirmed the diagnosis obtained by CVS and revealed no heterogeneity between tissues at this developmental stage. Further expansion occurred during the culture of CVS cells, indicating that direct prenatal diagnosis needs to be carried out on CVS tissue rather than on cultured cells. The intergenerational change of the repeat sequence from DM parent to DM offspring showed a significant parental sex difference for those parents with large expansions. Contraction of the unstable element was observed in the three males carrying the largest expansions and could explain why congenital DM is exclusively of maternal origin. 相似文献
49.
Marla Gearing Johannes Tigges Hiroshi Mori Suzanne S. Mirra 《Neurobiology of aging》1996,17(6):54-908
Because aged nonhuman primates show β-amyloid (Aβ) deposition in senile plaques and blood vessels similar to that seen in human aging and AD, we used C-terminal specific antibodies to Aβ40 and Aβ42 to investigate Aβ peptide length in the brains of 11 aged rhesus monkeys and a 59-year-old chimpanzee. In contrast to AD, where the earliest and most prominent form of Aβ in senile plaques is Aβ42, in the monkey, Aβ40-positive plaques predominated. The ratio of Aβ4): Aβ42-positive plaques averaged 2.08 in the monkey, as compared to a mean ratio of 0.37 in 68 human AD subjects (p < 0.001). Aβ40 was also more prominent in the chimpanzee than in humans. Possible explanations for these findings include species differences in the cleavage of Aβ from the amyloid precursor protein or in the activity of a putative carboxy peptidase forming Aβ40 from Aβ42 in situ. 相似文献
50.
Morphometric and immunohistochemical characterization of the intimal layer throughout the arterial system of elderly humans 总被引:3,自引:0,他引:3
Aryan Vink Arjan H. Schoneveld Marieke Poppen Dominique P. V. de Kleijn Cornelius Borst Gerard Pasterkamp 《Journal of anatomy》2002,200(1):97-103
The purpose of the present study was to obtain insight into the natural development of adaptive intimal thickening and atherosclerosis in the arterial tree of human species. The morphometry and composition of the intimal layer were studied in the arterial system of elderly individuals. Post mortem, a total of 703 arterial segments were dissected from 24 subjects (age 81.9 ± 9.9 years). From each subject, segments were dissected from 31 different arteries. Area stenosis [(plaque area/vessel area) × 100%] was determined in each segment. By (immuno)histochemistry, lipid content and the presence of inflammatory cells (macrophages) were assessed in the coronary, common carotid, brachial, radial and internal iliac arteries. Adaptive intimal thickening or advanced atherosclerosis was observed in all studied artery types. Area stenosis was highest in the coronary arteries (median, 30%) and lowest in the arteries supplying the brain (median, ≤ 7%). Plaques hiding a lipid‐rich core and plaques with macrophage infiltration were observed in all five selected artery types. In summary, the present observation demonstrates that intimal thickening is a systemic process involving most artery types. Within elderly humans, features of advanced atherosclerotic disease, a lipid‐rich core and macrophages, can be observed in the intimal layer of artery types that are recognised for their relation with clinical syndroms as well as artery types that remain clinically silent. 相似文献