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991.
随我国人民生活水平的提高及饮食习惯的改变,动脉粥样硬化(atherosclerosis,AS)已成为我国成人主要的死亡原因,严重威胁着人类健康。AS斑块中有多种病变合并存在,包括局部脂质和复合糖类聚集、纤维组织增生和钙质沉着形成斑块:继发性病变有斑块内出血 相似文献
992.
Herring A Lewejohann L Panzer AL Donath A Kröll O Sachser N Paulus W Keyvani K 《Neurobiology of disease》2011,42(3):530-538
Combined preventive and therapeutic physical/cognitive stimulation starting before disease onset and continuing over its progression reduce Alzheimer-related pathology in transgenic mice. We now report that exposure of TgCRND8 mice to an enriched environment as either a preventive or therapeutic approach is also capable to reduce Aβ burden, though with different plaque and cerebral amyloid angiopathy (CAA) morphology. Preventive treatment resulted in fewer and smaller plaques without affecting CAA, whereas in therapeutically treated mice beside reduction of CAA extent, numerous plaques of strongly diminished size were found, so that total plaque loads declined as well. These effects seemed to be mediated by distinct molecular pathways. In preventive but not therapeutic group a shift of Aβ(42/40) ratio towards Aβ(40) and up-regulation of Aβ clearing and degrading molecules were found. Contrariwise anti-oxidative defense mechanisms were induced only in therapy but not preventive group. We hypothesize that preventive enrichment lowers the amounts of plaque seeds and decelerates plaque growth by degradation and clearance of Aβ, while therapeutic enrichment mitigates growth and fusion of plaque seeds to large plaques by inhibiting further Aβ aggregation. This study provides an experimental basis for application of physical/cognitive training in both prophylaxis and therapy of Alzheimer's disease. 相似文献
993.
Immunotherapy for Alzheimer’s disease (AD) is effective in improving cognitive function in transgenic mouse models of AD. Because the AN1792 [beta-amyloid (Aβ) 1-42] vaccine was halted because of T cell mediated meningoencephalitis, many scientists are searching for a novel vaccine to avoid the T cell mediated immune response caused by the Aβ1-42. Importantly, the time when the immunization is begun can influence the immune effect. In this study, an adenovirus vaccine was constructed containing 10 × Aβ3-10 repeats and gene adjuvant CpG DNA. Transgenic AD mice were immunized intranasally for 3 months. After 10 × Aβ3-10 vaccine immunization, high titers of anti-Aβ42 IgG1 predominant antibodies were induced. In spatial learning ability and probe tests, the 10 × Aβ3-10 immunized mice showed significantly improved memories compared to control mice. The 10 × Aβ3-10 vaccine resulted in a robust Th2 dominant humoral immune response and reduced learning deficits in AD mice. In addition, the 10 × Aβ3-10 vaccine might be more efficient if administered before Aβ aggregation at an early stage in the AD mouse brain. Thus, the adenovirus vector encoding 10 × Aβ3-10 is a promising vaccine for AD. 相似文献
994.
Hiroki Okabe Shinjo Sonoda Yutaro Naka Koshi Setoyama Konosuke Inoue Toshiya Miura Reo Anai Yuki Tsuda Masaru Araki Yutaka Otsuji 《Internal medicine (Tokyo, Japan)》2021,60(14):2241
A 46-year-old man complained of chest pain at rest for the past three months. His symptoms gradually exacerbated and were suspected of being due to unstable angina. A coronary angiogram revealed focal tight stenosis at the proximal left anterior descending coronary artery with gross spastic coronary findings. Optical coherence tomography (OCT) revealed layered low-intensity structures with microvessels and the accumulation of macrophages, which indicated progressive stenosis with multiple-layered organized thrombus caused by coronary erosion. We treated the stenosis using a drug-coated balloon instead of drug-eluting stents. There was no restenosis, and OCT revealed good plaque healing at follow-up. This case suggests that the pre-interventional OCT plaque morphology can have a positive impact on the revascularization strategy. 相似文献
995.
目的:观察益气活血方对不稳定性心绞痛(UAP)易损斑块相关血清学指标MMP-9、sCD40L、sVCAM-1水平表达的影响。方法:选择51例冠心病不稳定性心绞痛(气虚血瘀证)患者,随机分为治疗组26例与对照组25例。2组均予常规西药治疗,治疗组加服益气活血方汤剂。治疗4周后,观察并比较2组患者治疗前后及治疗后反映冠状动脉粥样硬化斑块易损性的血清学检测指标MMP-9、sCD40L、sVCAM-1的变化。结果:治疗组患者血清中MMP-9、sCD40L、sVCAM-1的水平显著降低,与对照组比较差异有统计学意义(P0.05)。结论:益气活血方对反映冠状动脉粥样硬化斑块易损性的相关血清学检测指标有一定程度的影响,可显著降低患者MMP-9、sCD40L、sVCAM-1的表达,其机制可能通过抗血小板聚集、抗氧化、抑制炎症反应、保护内皮细胞功能等途径有效干预冠状动脉粥样硬化易损斑块,提高斑块的稳定性,从而预防心血管疾病的发生。 相似文献
996.
脑梗死(cerebral infarction,CI)是常见的脑血管疾病,严重影响人类的健康;动脉粥样硬化(atherosclerosis,AS)是脑梗死发生的一个重要因素,颈动脉粥样硬化斑块尤其是易损斑块的形成,是缺血性心脑血管病的共同基础;基质金属蛋白酶-2(MMP-2)可以对动脉粥样硬化斑块的纤维帽与基底膜产生裂解作用及参与血管内膜的炎性反应,其在血液中的病理性增高可影响动脉粥样硬化斑块的稳定性,是导致斑块破裂、引起脑梗死的关键因素之一,并对脑梗死的程度、预后有重要影响。 相似文献
997.
Fúcio SB Carvalho FG Sobrinho LC Sinhoreti MA Puppin-Rontani RM 《Journal of dentistry》2008,36(10):833-839
OBJECTIVE: To evaluate the effects of Streptococcus mutans biofilm/restorative materials interaction on surface roughness, hardness and morphology of materials tested. METHODS: Empress 2 (E2), Filtek Supreme (FS), Vitremer (V) and Ketac Molar Easymix (KM) were tested. Twenty-five disks of each material were made and divided into three storage groups: (1) 100% relative humidity (n=5); (2) growth medium (BHI and 1% sucrose) (n=5); (3) S. mutans biofilm-growth medium (n=15). Before storage, hardness measurements were immediately obtained from group 1 specimens. After 30 days of storage, the specimens were cleaned in order to obtain the surface roughness and hardness values, besides morphology analysis by scanning electron microscopy. RESULTS: The surface roughness and hardness values obtained from E2 and FS specimens did not present statistically significant differences among the groups 1, 2 and 3 and between immediate and 30-day-old specimens of each material. However, group 3 specimens of V and KM showed statistically significant higher surface roughness means than other groups. Group 1 specimens of V and KM also showed higher hardness values than the immediate values. Group 3 specimens of V presented decreased hardness values compared with other groups. The scanning electron micrographs showed an increase in surface degradation from group 1 to group 3 for FS, V and KM. CONCLUSIONS: Thirty-day-old biofilm promotes a negative effect on the surface morphology of FS, V and KM, on the surface roughness of V and KM and on the hardness of V. 相似文献
998.
Microbial complexes in supragingival plaque 总被引:1,自引:0,他引:1
Background/aims: To examine microbial communities in supragingival biofilm samples.
Methods: Supragingival plaque samples were taken from 187 subjects at baseline ( n = 4745). Fifty-five subjects provided supragingival plaque samples at 1–7 days after professional tooth cleaning ( n = 1456); 93 subjects provided 8044 samples between 3 and 24 months post-therapy. All samples were individually analyzed for their content of 40 bacterial species using checkerboard DNA–DNA hybridization. Microbial associations among species were sought using cluster analysis and community ordination techniques for the three groups separately.
Results: Six complexes were formed for the baseline samples. Similar complexes were formed for the samples taken 3–24 months post-therapy. However, distinct changes were observed in microbial communities in samples taken during the 7 days of plaque redevelopment. The complexes related to clinical parameters of periodontal disease.
Conclusion: There were specific microbial complexes in supragingival plaque that were similar to those found in subgingival plaque samples with a few minor differences. The relation of previously unclustered taxa to the complexes was also described. 相似文献
Methods: Supragingival plaque samples were taken from 187 subjects at baseline ( n = 4745). Fifty-five subjects provided supragingival plaque samples at 1–7 days after professional tooth cleaning ( n = 1456); 93 subjects provided 8044 samples between 3 and 24 months post-therapy. All samples were individually analyzed for their content of 40 bacterial species using checkerboard DNA–DNA hybridization. Microbial associations among species were sought using cluster analysis and community ordination techniques for the three groups separately.
Results: Six complexes were formed for the baseline samples. Similar complexes were formed for the samples taken 3–24 months post-therapy. However, distinct changes were observed in microbial communities in samples taken during the 7 days of plaque redevelopment. The complexes related to clinical parameters of periodontal disease.
Conclusion: There were specific microbial complexes in supragingival plaque that were similar to those found in subgingival plaque samples with a few minor differences. The relation of previously unclustered taxa to the complexes was also described. 相似文献
999.
Grande SR Imbronito AV Okuda OS Lotufo RF Magalhães MH Nunes FD 《Journal of clinical periodontology》2008,35(10):838-845
Aim: The objective of this study was to compare the frequency of herpes simplex virus type 1 (HSV‐1), Epstein–Barr virus (EBV) and human cytomegalovirus (HCMV) in subgingival plaque, saliva and peripheral blood of HIV‐positive and‐negative patients with periodontal disease. Material and Methods: Fifty HIV‐positive subjects (23 with gingivitis, 27 with periodontitis) and 50 healthy HIV‐negative patients with chronic periodontitis were included in the study. Parameters of probing depth (PD), clinical attachment level (CAL), gingival index and plaque index were recorded. The samples were processed for viral identification by the nested polymerase chain reaction technique. Results: HCMV was the most prevalent virus in HIV‐positive (82%) and‐negative patients (84%), and the detection in the three samples was similar (p>0.05). HSV‐1 was the least prevalent virus in both groups, being detected in similar frequencies in oral sites and in peripheral blood. EBV‐1 was found more frequently in saliva and subgingival plaque of HIV‐positive patients than in HIV‐negative patients (p0.05). Conclusions: EBV‐1 was more frequently recovered in oral sites of HIV‐positive patients than in HIV‐negative patients. 相似文献
1000.
Shibli JA Melo L Ferrari DS Figueiredo LC Faveri M Feres M 《Clinical oral implants research》2008,19(10):975-982
Objectives: The purpose of this study was to compare the microbial composition of supra‐ and subgingival biofilm in subjects with and without peri‐implantitis. Material and methods: Forty‐four subjects (mean age 48.9 ± 13.51 years) with at least one implant restored and functional for at least 2 years were assigned to two groups: a peri‐implantitis group (n=22), consisting of subjects presenting peri‐implant sites with radiographic defects >3 mm, bleeding on probing and/or suppuration; and a control group (n=22), consisting of subjects with healthy implants. The clinical parameters evaluated were plaque index, gingival bleeding, bleeding on probing, suppuration, probing depth and clinical attachment level. Supra‐ and subgingival biofilm samples were taken from the deepest sites of each implant and analyzed for the presence of 36 microorganisms by checkerboard DNA–DNA hybridization. Results: Higher mean counts of Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia were observed in the peri‐implantitis group, both supra‐ and subgingivally (P<0.05). The proportions of the pathogens from the red complex were elevated, while host‐compatible beneficial microbial complexes were reduced in diseased compared with healthy implants. The microbiological profiles of supra‐ and subgingival environments did not differ substantially within each group. Conclusion: Marked differences were observed in the composition of supra‐ and subgingival biofilm between healthy and diseased implants. The microbiota associated with peri‐implantitis was comprised of more periodontal pathogenic bacterial species, including the supragingival biofilm. 相似文献