Recent studies have demonstrated the deposition of amyloid beta (A beta) protein with carboxyl- and aminoterminal heterogeneity in cortical and cerebrovascular deposits of Alzheimer's disease (AD). Using carboxyl end-terminal specific antibodies to A beta peptides, we examined the immunocytochemical distribution of A beta 40 and A beta 42 species in brain tissue from a Swedish subject with familial AD (FAD) bearing the double mutation at codons 670/671 in the amyloid beta precursor protein (A beta PP), and from subjects with Down's syndrome and sporadic AD. In the Swedish subject, we found profound parenchymal A beta deposits and cerebral amyloid angiopathy in all four cortical lobes and cerebellum. A beta 42 was evident in almost all parenchymal deposits as well as many vascular deposits. Although A beta 40 was present in meningeal and intraparenchymal vessels, deposits containing this shorter peptide reactivity were sparse. Surprisingly, our observations in Swedish FAD showing a remarkable abundance of A beta 42 in both parenchymal and vascular deposits were qualitatively similar to the Down's syndrome and most sporadic AD cases, and to previously published A beta PP717 FAD. While previous transfection studies in different cell cultures indicate substantially increased soluble A beta production and A beta 40 species to be predominant, it would appear that the double A beta PP mutations in Swedish FAD largely result in the deposition of the longer A beta 42 in vivo.
Age dynamics and seasonal variations in cerebral blood flow was studied by means of transcranial Doppler in 95 the natives of the Arkhangelsk region school students aged 7 to 18 years. The results of longitudinal (from 2005 to 2014) study of students are presented. The linear blood flow velocity (BFV) showed gradual declining from junior to senior school age, and BFV were in the middle cerebral artery below average, and in the basilar artery--above mid latitude standards. The influence of the seasonal factor is more pronounced in the younger (for boys) and intermediate (for girls) age group and leveled in the older group. The largest seasonal changes were obtained in BFV in carotid arteries, the relative constancy--in BFV in the basilar artery. Estimated by the resistivity index RI circulatory resistance in the younger and intermediate school students groups decreased in the carotid arteries in the spring and summer, and in the posterior cerebral artery territory--in the winter. BFV rate variability identifies groups of children with varying degrees of "sensitivity" to the influence of seasonal factors.
The impact of the delay in therapeutic intervention at the acute stage of the disease on restitution of neurological functions is shown in 493 patients with ischemic brain stroke, admitted to an emergency neurology unit. The regress of neurological symptoms was notable in 62.9% of patients who were treated by the 6th hour since the disease onset. With the therapy instituted after 6 h, the regress was evident in 49.8% of cases. The treatment impact on the restoration of neurological functions was analyzed in 273 cases.
22 healthy subjects aged from 25 to 45, mean age 32.7+/-5.3, have been observed. Every patient was subjected to diagnosing cerebral hemodynamics carried out every 7 days during 6 weeks. The circulation of common carotid artery, middle cerebral arteries and internal jugular arteries has been studied by means of LOGIQ-500MD (GE MS, USA) apparatus. The determination of arterio-venouse balance of cerebral hemodynamics was shown to be worthwhile for common carotid artery and its homolateral internal jugular artery. Arterio-venouse balance is presented as a ratio of circulation blood velocity in common carotid and internal jugular arteries.
Patients with Alzheimer's disease have reduced cerebral blood flow measured by arterial spin labelling magnetic resonance imaging, but it is unclear how this is related to amyloid-ß pathology. Using 182 subjects from the Alzheimer's Disease Neuroimaging Initiative we tested associations of amyloid-ß with regional cerebral blood flow in healthy controls (n = 51), early (n = 66) and late (n = 41) mild cognitive impairment, and Alzheimer's disease with dementia (n = 24). Based on the theory that Alzheimer's disease starts with amyloid-ß accumulation and progresses with symptoms and secondary pathologies in different trajectories, we tested if cerebral blood flow differed between amyloid-ß-negative controls and -positive subjects in different diagnostic groups, and if amyloid-ß had different associations with cerebral blood flow and grey matter volume. Global amyloid-ß load was measured by florbetapir positron emission tomography, and regional blood flow and volume were measured in eight a priori defined regions of interest. Cerebral blood flow was reduced in patients with dementia in most brain regions. Higher amyloid-ß load was related to lower cerebral blood flow in several regions, independent of diagnostic group. When comparing amyloid-ß-positive subjects with -negative controls, we found reductions of cerebral blood flow in several diagnostic groups, including in precuneus, entorhinal cortex and hippocampus (dementia), inferior parietal cortex (late mild cognitive impairment and dementia), and inferior temporal cortex (early and late mild cognitive impairment and dementia). The associations of amyloid-ß with cerebral blood flow and volume differed across the disease spectrum, with high amyloid-ß being associated with greater cerebral blood flow reduction in controls and greater volume reduction in late mild cognitive impairment and dementia. In addition to disease stage, amyloid-ß pathology affects cerebral blood flow across the span from controls to dementia patients. Amyloid-ß pathology has different associations with cerebral blood flow and volume, and may cause more loss of blood flow in early stages, whereas volume loss dominates in late disease stages.
Diving is associated with a risk of cerebral decompression illness, and the prevalence of neurological symptoms is higher in divers compared with control groups. Microvascular dysfunction due to gas microembolism and exposure to hyperoxia are possible mechanisms, which may result in cerebral diffusion and perfusion deficits.
To investigate if possible functional derangements of the microvasculature and microstructure would be more prevalent among symptomatic divers.
Magnetic resonance imaging (MRI) was performed in 91 former divers and 45 controls. Individual parametric images of apparent diffusion coefficient (ADC), cerebral blood flow (CBF), cerebral blood volume (CBV), and mean transit time (MTT) were generated on the basis of diffusion- and perfusion-weighted imaging. To identify regions with statistically significant differences between groups (P
The purpose of this study was to determine the correlation between cerebral perfusion levels, Neck Disability Index (NDI) scores, and spinal joint fixations in patients with neck pain.
Forty-five adult patients (29 were female) with chronic neck/upper thoracic pain during exacerbation were studied. The subjects were grouped according to NDI scores: mild, moderate, and severe. The number of painful/blocked segments in the cervical and upper thoracic spine and costovertebral joints, pain intensity using the visual analog scale, and regional cerebral blood flow of the brain using single-photon emission computed tomography (SPECT) were obtained. The SPECT was analyzed semiquantitatively. Analysis of variance tests were conducted on total SPECT scores in each of the NDI groups (P
An analysis of frequency, structure and risk factors of cerebrovascular disease (CVD) in women with systemic lupus erythematosus (SLE) is presented. A study included 143 women (mean age 36.7±12.7 years) with confirmed systemic lupus erythematosus. Acute or chronic CVD was found almost in a half of cases. Among acute blood circulation disorders, there was a high frequency of brain ischemia with equal number of cases with transitory ischemic attacks and ischemic strokes. Chronic cerebrovascular disease was mostly represented by chronic brain ischemia. The basic (standard) and some specific (non-standard) risk factors of the development of cerebrovascular disease in women with SLE are revealed. Based on the features of a clinical course of SLE, we identified the correlations of acute blood circulation disorders with duration, course and activity of disease. The paper presents original methods of the mathematical prediction of the development of chronic brain ischemia in women with SLE without clinical manifestations of cerebrovascular pathology. The tactics of prophylactic medical examinations depending on the results of the prediction model was proposed. The authors present an approximate list of preventive measures based on the use of systems of individual prediction.
The article presents the results of Doppler examination of 44 healthy children and 180 children with chronic pathology of alimentary tract. All the patients underwent the reactivity test of the middle cerebral artery after graduated cool-water bearing. Dynamics of the studied data are presented in the article. The obtained results indicate more distinct changes of function of the vegetative nervous system in children with organic pathology of the alimentary canal.
BACKGROUND: Deep hypothermic circulatory arrest is an effective method of cerebral protection, but it is associated with long cardiopulmonary bypass times and coagulation disturbances. Previous studies have shown that retrograde cerebral perfusion can improve neurologic outcomes after prolonged hypothermic circulatory arrest. We tested the hypothesis that deep hypothermic retrograde cerebral perfusion could improve cerebral outcome during moderate hypothermic circulatory arrest. METHODS: Twelve pigs (23-29 kg) were randomly assigned to undergo either retrograde cerebral perfusion (15 degrees C) at 25 degrees C or hypothermic circulatory arrest with the head packed in ice at 25 degrees C for 45 minutes. Flow was adjusted to maintain superior vena cava pressure at 20 mm Hg throughout retrograde cerebral perfusion. Hemodynamic, electrophysiologic, metabolic, and temperature monitoring were carried out until 4 hours after the start of rewarming. Daily behavioral assessment was performed until elective death on day 7. A postmortem histologic analysis of the brain was carried out on all animals. RESULTS: In the retrograde cerebral perfusion group, 5 (83%) of 6 animals survived 7 days compared with 2 (33%) of 6 in the hypothermic circulatory arrest group. Complete behavioral recovery was seen in 4 (67%) animals after retrograde cerebral perfusion but only in 1 (17%) animal after hypothermic circulatory arrest. Postoperative levels of serum lactate were higher, and blood pH was lower in the hypothermic circulatory arrest group. There were no significant hemodynamic differences between the study groups. CONCLUSIONS: Cold hypothermic retrograde cerebral perfusion during moderate hypothermic circulatory arrest seems to improve neurologic outcome compared with moderate hypothermic circulatory arrest with the head packed in ice.