999 resultados para vascular lesions
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The relative contributions of Alzheimer disease (AD) and vascular lesion burden to the occurrence of cognitive decline are more difficult to define in the oldest-old than they are in younger cohorts. To address this issue, we examined 93 prospectively documented autopsy cases from 90 to 103 years with various degrees of AD lesions, lacunes, and microvascular pathology. Cognitive assessment was performed prospectively using the Clinical Dementia Rating scale. Neuropathologic evaluation included the Braak neurofibrillary tangle (NFT) and β-amyloid (Aβ) protein deposition staging and bilateral semiquantitative assessment of vascular lesions. Statistics included regression models and receiver operating characteristic analyses. Braak NFTs, Aβ deposition, and cortical microinfarcts (CMIs) predicted 30% of Clinical Dementia Rating variability and 49% of the presence of dementia. Braak NFT and CMI thresholds yielded 0.82 sensitivity, 0.91 specificity, and 0.84 correct classification rates for dementia. Using these threshold values, we could distinguish 3 groups of demented cases and propose criteria for neuropathologic definition of mixed dementia, pure vascular dementia, and AD in very old age. Braak NFT staging and severity of CMI allow for defining most of demented cases in the oldest-old. Most importantly, single cutoff scores for these variables that could be used in the future to formulate neuropathologic criteria for mixed dementia in this age group were identified.
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The occurrence of microvascular and small macrovascular lesions and Alzheimer's disease (AD)-related pathology in the aging human brain is a well-described phenomenon. Although there is a wide consensus about the relationship between macroscopic vascular lesions and incident dementia, the cognitive consequences of the progressive accumulation of these small vascular lesions in the human brain are still a matter of debate. Among the vast group of small vessel-related forms of ischemic brain injuries, the present review discusses the cognitive impact of cortical microinfarcts, subcortical gray matter and deep white matter lacunes, periventricular and diffuse white matter demyelinations, and focal or diffuse gliosis in old age. A special focus will be on the sub-types of microvascular lesions not detected by currently available neuroimaging studies in routine clinical settings. After providing a critical overview of in vivo data on white matter demyelinations and lacunes, we summarize the clinicopathological studies performed by our center in large cohorts of individuals with microvascular lesions and concomitant AD-related pathology across two age ranges (the younger old, 65-85 years old, versus the oldest old, nonagenarians and centenarians). In conjunction with other autopsy datasets, these observations fully support the idea that cortical microinfarcts are the only consistent determinant of cognitive decline across the entire spectrum from pure vascular cases to cases with combined vascular and AD lesion burden.
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BACKGROUND AND PURPOSE: Most of the neuropathological studies in brain aging were based on the assumption of a symmetrical right-left hemisphere distribution of both Alzheimer disease and vascular pathology. To explore the impact of asymmetrical lesion formation on cognition, we performed a clinicopathological analysis of 153 cases with mixed pathology except macroinfarcts. METHODS: Cognitive status was assessed prospectively using the Clinical Dementia Rating scale; neuropathological evaluation included assessment of Braak neurofibrillary tangle and Ass deposition staging, microvascular pathology, and lacunes. The right-left hemisphere differences in neuropathological scores were evaluated using the Wilcoxon signed rank test. The relationship between the interhemispheric distribution of lesions and Clinical Dementia Rating scores was assessed using ordered logistic regression. RESULTS: Unlike Braak neurofibrillary tangle and Ass deposition staging, vascular scores were significantly higher in the left hemisphere for all Clinical Dementia Rating scores. A negative relationship was found between Braak neurofibrillary tangle, but not Ass staging, and vascular scores in cases with moderate to severe dementia. In both hemispheres, Braak neurofibrillary tangle staging was the main determinant of cognitive decline followed by vascular scores and Ass deposition staging. The concomitant predominance of Alzheimer disease and vascular pathology in the right hemisphere was associated with significantly higher Clinical Dementia Rating scores. CONCLUSIONS: Our data show that the cognitive impact of Alzheimer disease and vascular lesions in mixed cases may be assessed unilaterally without major information loss. However, interhemispheric differences and, in particular, increased vascular and Alzheimer disease burden in the right hemisphere may increase the risk for dementia in this group.
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The systemic aspect of vascular damage induced by angiotensin II (ANG II) has been poorly explored in the literature. Considering the presence of ANG II and its specific receptor AT1, in several organs, all tissues might be potentially affected by its effects. The aims of this study were: To evaluate the early histological changes in the heart, liver and kidneys, produced by ANG II infusion, to evaluate the protective effect of losartan. Wistar rats were distributed into three groups: control (no treatment), treated with ANG II, and treated with ANG II + losartan. ANG II was continuously infused over 72 hours by subcutaneous osmotic pumps. Histological sections of the myocardium, kidneys and liver were stained and observed for the presence of necrosis. There were ANG II-induced perivascular inflammation and necrosis of the arteriolar wall in the myocardium, kidney, and liver by, which were partially prevented by losartan. There was no significant correlation between heart and kidney damage. Tissue lesion severity was lower than that of vascular lesions, without statistical difference between groups. ANG II causes vascular injury in the heart, kidneys and liver, indicating a systemic vasculotoxic effect; the mechanisms of damage/protection vary depending on the target organ; perivascular lesions may occur even when anti-hypertensive doses of losartan are used.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The diagnosis of vascular dementia (VaD) describes a group of various vessel disorders with different types of vascular lesions that finally contribute to the development of dementia. Most common forms of VaD in the elderly brain are subcortical vascular encephalopathy, strategic infarct dementia, and the multi infarct encephalopathy. Hereditary forms of VaD are rare. Most common is the cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). Sporadic forms of VaD are caused by degenerative vessel disorders such as atherosclerosis, small vessel disease (SVD) including small vessel arteriosclerosis, arteriolosclerosis, and lipohyalinosis, and cerebral amyloid angiopathy (CAA). Less frequently inflammatory vessel disorders and tumor-associated vessel lesions (e. g. angiocentric T-cell or angiotropic large cell lymphoma) can cause symptoms of dementia. Here, we review and discuss the impact of vessel disorders to distinct vascular brain tissue lesions and to the development of dementia in elderly individuals. The impact of coexisting neurodegenerative pathology in the elderly brain to VaD as well as the correlation between SVD and CAA expansion in the brain parenchyma with that of Alzheimer's disease (AD)-related pathology is highlighted. We conclude that "pure" VaD is rare and most frequently caused by infarctions. However, there is a significant contribution of vascular lesions and vessel pathology to the development of dementia that may go beyond tissue damage due to vascular lesions. Insufficient blood blow and alterations of the perivascular drainage mechanisms of the brain may also lead to a reduced protein clearance from extracellular space and subsequent increase of proteins in the brain parenchyma, such as the amyloid beta-protein, and foster, thereby, the development of AD-related neurodegeneration. As such, it seems to be important for clinical practice to consider treatment of potentially coexisting AD pathology in cognitively impaired patients with vascular lesions. (C) 2012 Elsevier Inc. All rights reserved.
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To evaluate the therapeutic effect of infliximab in patients with inflammatory vascular lesions due to Behçet's disease (BD).
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Thoracic injuries in general are of great importance due to their high incidence and high mortality. Thoracic impalement injuries are rare but severe due to the combination of cause, effect and result. This study's primary objective is to report the case of a young man who was impaled by a two-wheeled horse carriage shaft while crashing his motorcycle in a rural zone. An EMT-B ferry was called at the crash scene and a conscious patient was found, sustaining a severe impalement injury to the left hemithorax, suspended over the floor by the axial skeleton with the carriage shaft coming across his left chest. As a secondary objective, a literature review of thoracic impalement injuries is performed. Cases of thoracic impalement injury require unique and individualized care based on injury severity and affected organs. Reported protocols for managing impalement injuries are entirely anecdotal, with no uniformity on impaled patient's approach and management. In penetrating trauma, it is essential not to remove the impaled object, so that possible vascular lesions remain buffered by the object, avoiding major bleeding and exsanguination haemorrhage. Severed impaled thoracic patients should be transferred to a specialist centre for trauma care, as these lesions typically require complex multidisciplinary treatment. High-energy thoracic impalement injuries are rare and hold a high mortality rate, due to the complexity of trauma and associated injuries such as thoracic wall and lung lesions. Modern medicine still seems limited in cases of such seriousness, not always with satisfactory results.
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PURPOSE: Postmortem computed tomography angiography (PMCTA) was introduced into forensic investigations a few years ago. It provides reliable images that can be consulted at any time. Conventional autopsy remains the reference standard for defining the cause of death, but provides only limited possibility of a second examination. This study compares these two procedures and discusses findings that can be detected exclusively using each method. MATERIALS AND METHODS: This retrospective study compared radiological reports from PMCTA to reports from conventional autopsy for 50 forensic autopsy cases. Reported findings from autopsy and PMCTA were extracted and compared to each other. PMCTA was performed using a modified heart-lung machine and the oily contrast agent Angiofil® (Fumedica AG, Muri, Switzerland). RESULTS: PMCTA and conventional autopsy would have drawn similar conclusions regarding causes of death. Nearly 60 % of all findings were visualized with both techniques. PMCTA demonstrates a higher sensitivity for identifying skeletal and vascular lesions. However, vascular occlusions due to postmortem blood clots could be falsely assumed to be vascular lesions. In contrast, conventional autopsy does not detect all bone fractures or the exact source of bleeding. Conventional autopsy provides important information about organ morphology and remains the only way to diagnose a vital vascular occlusion with certitude. CONCLUSION: Overall, PMCTA and conventional autopsy provide comparable findings. However, each technique presents advantages and disadvantages for detecting specific findings. To correctly interpret findings and clearly define the indications for PMCTA, these differences must be understood.
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We report the clinical findings of a 40-year-old woman with recurrent migraine presenting with Wernicke's aphasia in accordance with the results of a standardized battery for language assessment (Boston Aphasia Diagnostic Examination). The patient had no evidence of parenchymal or vascular lesions on MRI and showed delta and theta slowing over the left posterior temporal leads on the EEG. Although the acute onset of a fluent aphasia suggested stroke as a likely etiology, the recurrence of aphasia as the initial symptom of migraine was related to cortical spreading depression and not to stroke.
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Kaposiform hemangioendothelioma (KHE) and tufted angioma (TA) are rare tumors mainly occurring in early childhood. Our recent results showed that ectopic overexpression of human Prox1 gene, a lymphatic endothelial nuclear transcription factor, promoted an aggressive behavior in 2 murine models of KHE. This dramatic Prox1-induced phenotype prompted us to investigate immunohistochemical staining pattern of Prox1, podoplanin (D2-40), LYVE-1, and Prox1/CD34 as well as double immunofluorescent staining pattern of LYVE-1/CD31 in KHE and TA, compared with other pediatric vascular tumors. For this purpose, we examined 75 vascular lesions: KHE (n=18), TA (n=13), infantile hemangioma (n=13), pyogenic granuloma (n=18), and granulation tissue (n=13). Overall, KHE and TA shared an identical endothelial immunophenotype: the neoplastic spindle cells were Prox1, podoplanin, LYVE-1, CD31, and CD34, whereas endothelial cells within glomeruloid foci were Prox1, podoplanin, LYVE-1, CD31, and CD34. The lesional cells of all infantile hemangiomas and pyogenic granulomas were negative for Prox1 in the presence of positive internal control. These findings provide immunophenotypic evidence to support a preexisting notion that KHE and TA are closely related, if not identical. Overall, our results show, for the first time, that Prox1 is an immunohistochemical biomarker helpful in confirming the diagnosis of KHE/TA and in distinguishing it from infantile hemangioma and pyogenic granuloma.
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Skin, arteries and nerves of the upper extremities can be affected by vibration exposure. Recent advances in skin and vascular biology as well as new investigative methods, have shown that neurovascular symptoms may be due to different vascular and neurological disorders which should be differentiated if proper management is to be evaluated. Three types of vascular disorder can be observed in the vibration white finger: digital organic microangiopathy, a digital vasospastic phenomenon and arterial thrombosis in the upper extremities. An imbalance between endothelin-1 and calcitonin-gene-related peptide is probably responsible for the vasospastic phenomenon. Moreover, paresthesiae can be due to either a diffuse vibration neuropathy or a carpal tunnel syndrome. A precise diagnosis is then necessary to adapt the treatment to individual cases. A classification describing the type and severity of the vascular lesions is presented. Asymptomatic lesions are included for adequate epidemiological studies and risk assessment of vibrating tools. Monitoring of vibration exposed workers should include not only a questionnaire about symptoms, but also a clinical evaluation including diagnostic tests for the screening of early asymptomatic neurovascular injuries.
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Angiogenesis has been recognised as a precursor of fibrosis in several pathologic conditions. Its participation has been demonstrated in schistosomiasis, both during periovular granuloma formation and in the genesis of schistosomal periportal fibrosis. Paradoxically, proliferation of new blood vessels, accompanied by production of vascular-endothelial growth factor, appeared prominent during fibrosis regression months after curative treatment of schistosomiasis. Thus, angiogenesis in schistosomiasis seems to have a two-way mode of action, participating both in fibrogenesis and in fibrosis degradation. Morphological observations presented here are in keeping with the possibility that, in the first case, angiogenesis allows pericytes to come in great numbers to the site of lesions and be detached from capillary walls and transformed into myofibroblasts, which are important extra-cellular matrix forming cells. During post-curative fibrosis regression, actin-containing pericytes appeared at various foci of tissue remodelling, especially at sites of repair of vascular lesions. The molecular and cell factors involved in both situations seem to be important subjects in need of further investigations and the schistosomiasis model certainly will be of great avail in this regard.
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Knowledge on the patterns of repetition amongst individuals who develop language deficits in association with right hemisphere lesions (crossed aphasia) is very limited. Available data indicate that repetition in some crossed aphasics experiencing phonological processing deficits is not heavily influenced by lexical-semantic variables (lexicality, imageability, and frequency) as is regularly reported in phonologically-impaired cases with left hemisphere damage. Moreover, in view of the fact that crossed aphasia is rare, information on the role of right cortical areas and white matter tracts underpinning language repetition deficits is scarce. In this study, repetition performance was assessed in two patients with crossed conduction aphasia and striatal/capsular vascular lesions encompassing the right arcuate fasciculus (AF) and inferior frontal-occipital fasciculus (IFOF), the temporal stem and the white matter underneath the supramarginal gyrus. Both patients showed lexicality effects repeating better words than non-words, but manipulation of other lexical-semantic variables exerted less influence on repetition performance. Imageability and frequency effects, production of meaning-based paraphrases during sentence repetition, or better performance on repeating novel sentences than overlearned clichés were hardly ever observed in these two patients. In one patient, diffusion tensor imaging disclosed damage to the right long direct segment of the AF and IFOF with relative sparing of the anterior indirect and posterior segments of the AF, together with fully developed left perisylvian white matter pathways. These findings suggest that striatal/capsular lesions extending into the right AF and IFOF in some individuals with right hemisphere language dominance are associated with atypical repetition patterns which might reflect reduced interactions between phonological and lexical-semantic processes.
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Investigation of violent death, especially cases of sharp trauma and gunshot, is an important part of medico-legal investigations. Beside the execution of a conventional autopsy, the performance of a post-mortem Multi-Detector Computed Tomography (MDCT)-scan has become a highly appreciated tool. In order to investigate also the vascular system, post-mortem CT-angiography has been introduced. The most studied and widespread technique is the Multi-phase post-mortem CT-angiography (MPMCTA). Its sensitivity to detect vascular lesions is even superior to conventional autopsy. The application of MPMCTA for cases of gunshot and sharp-trauma is therefore an obvious choice, as vascular lesions are common in such victims. In most cases of sharp trauma and in several cases of gunshots, death can be attributed to exsanguinations. MPMCTA is able to detect the exact source of bleeding and also to visualize trajectories, which are of most importance in these cases. The reconstructed images allow to clearly visualizing the trajectory in a way that is easily comprehensible for not medically trained legal professionals. The sensitivity of MPMCTA for soft tissue and organ lesions approximately matches the sensitivity of conventional autopsy. However, special care, experience and effective use of the imaging software is necessary for performing the reconstructions of the trajectory. Large volume consuming haemorrhages and shift of inner organs are sources of errors and misinterpretations. This presentation shall give an overview about the advantages and limitations of the use of MPMCTA for investigating cases of gunshot and sharp-trauma.