Neuropathologic Correlates of White Matter Hyperintensities in a Community-Based Cohort of Older Adults.

BACKGROUND: The association of white matter hyperintensities (WMH) with age-related vascular and neurodegenerative pathologies remains incompletely understood. OBJECTIVE: The objective of this work was to elucidate the neuropathologic correlates of WMH in a large community-based cohort of older adults. METHODS: Cerebral hemispheres from 603 community-based older adults were imaged with MRI ex vivo. All participants underwent annual clinical evaluation, cognitive assessment, and neuropathologic examination. WMH burden was assessed using a modified Fazekas rating scale. Multiple ordinal logistic regression was used to test the association of WMH burden with an array of age-related neuropathologies, adjusting for demographics. Mixed effects models of cognition controlling for neuropathologies and demographics were used to determine whether WMH burden contributes to cognitive decline beyond measured pathologies. RESULTS: WMH burden in the whole group was associated with both vascular and Alzheimer's disease (AD) pathologies: arteriolosclerosis (p < 10-4), gross (p < 10-4), and microscopic infarcts (p = 0.04), and amyloid-ß plaques (p = 0.028). In non-demented participants (mild or no cognitive impairment) (N = 332), WMH burden was related to gross infarcts (p = 10-4) and arteriolosclerosis (p < 10-4), but not to AD pathology. Similarly, in those with no cognitive impairment (N = 178), WMH burden was related to gross infarcts (p = 8×10-4) and arteriolosclerosis (p = 0.014). WMH burden was associated with faster decline in perceptual speed in both the whole (p = 0.038) and non-demented (p = 0.006) groups. CONCLUSION: WMH burden has independent associations with vascular pathologies in older adults regardless of clinical status, and with AD pathology later in the progression of AD. Moreover, WMH burden may reflect additional tissue injury not captured with traditional neuropathologic indices.

Rhynchophylline Protects Against the Amyloid ß-Induced Increase of Spontaneous Discharges in the Hippocampal CA1 Region of Rats.

Accumulated soluble amyloid ß (Aß)-induced aberrant neuronal network activity has been recognized as a key causative factor leading to cognitive deficits which are the most outstanding characteristic of Alzheimer's disease (AD). As an important structure associated with learning and memory, the hippocampus is one of the brain regions that are impaired very early in AD, and the hippocampal CA1 region is selectively vulnerable to soluble Aß oligomers. Our recent study showed that soluble Aß1-42 oligomers induced hyperactivity and perturbed the firing patterns in hippocampal neurons. Rhynchophylline (RIN) is an important active tetracyclic oxindole alkaloid isolated from Uncaria rhynchophylla which is a traditional Chinese medicine and often used to treat central nervous system illnesses such as hypertension, convulsions, tremor, stroke etc. Previous evidence showed that RIN possessed neuroprotective effects of improving the cognitive function of mice with Alzheimer-like symptoms. In the present study, we aimed to investigate the protective effect of RIN against soluble Aß1-42 oligomers-induced hippocampal hyperactivity. The results showed that (1) the mean frequency of spontaneous discharge was increased by the local application of 3 µM soluble Aß1-42 oligomers; (2) 30 µM RIN did not exert any obvious effects on basal physiological discharges; and (3) treatment with RIN effectively inhibited the soluble Aß1-42 oligomers-induced enhancement of spontaneous discharge, in a concentration-dependent manner with an IC50 = 9.0 µM. These in vivo electrophysiological results indicate that RIN can remold the spontaneous discharges disturbed by Aß and counteract the deleterious effect of Aß1-42 on neural circuit. The experimental findings provide further evidence to affirm the potential of RIN as a worthy candidate for further development into a therapeutic agent for AD.

Effects of fimbria-fornix lesion and amyloid pathology on spatial learning and memory in transgenic APP+PS1 mice.

Transgenic mice carrying mutated human amyloid precursor protein (APPswe) and presenilin (PS1, A246E) genes develop first amyloid plaques around 9 months of age, but up to 18 months of age, amyloid depositions in these mice were largely restricted to the hippocampus, subiculum, and neocortex. To assess the behavioral consequences of amyloid accumulation in the hippocampal formation, we compared the effects of APP+PS1 (AP) genotype and fimbria-fornix (FFX) transection, either alone or combined, on various spatial learning and memory tasks. Both FFX-lesioned and AP mice were impaired in spatial navigation in the water maze, a typical hippocampal dependent task. Conversely, neither group of mice was impaired in a win-stay version of the radial arm maze (RAM) or position discrimination in the T-maze, tasks that do not depend on the hippocampus. FFX-lesioned mice were impaired in the win-shift version of the RAM, and in spontaneous and rewarded alternation in the T-maze, while AP mice performed equal to non-transgenic controls in all these working memory tasks, except long-term retention of the RAM task. AP mice thus appear to have a selective deficit in hippocampal dependent long-term memory, as do Alzheimer patients at early stage of the disease.

Early liver transplantation is essential for familial amyloidotic polyneuropathy patients' quality of life.

Nineteen patients, who had undergone liver transplantation for familial amyloidotic polyneuropathy, had answered a quality of life questionnaire including 61 questions on somatic and mental symptoms, social aspects of life, confidence and satisfaction before, one year, and two years after transplantation. We found that patient satisfaction was generally good two years or more after the transplantation. Most of the patients were very or quite satisfied with the result. All of them had the drive to go on and felt hopeful about the future. However, on the second follow-up, 37% of the patients noted that they felt more insecure in their everyday life and there was a significant difference between the two assessments. The diarrhea score became worse between one and two years after the transplantation and was closely related to the duration of the gastrointestinal symptoms and to the duration of the disease before transplantation. The mental symptoms also increased significantly between the evaluations and this related to the severity of the somatic symptoms. Our conclusion is that liver transplantation should be performed before advanced somatic symptoms start to develop in order to improve the patients' chances of a good quality of life following liver transplantation.

Family members' experience of familial amyloidotic polyneuropathy disease--an infernal struggle and a fact of life.

Familial amyloidotic polyneuropathy is a fatal, hereditary, systemic, progressive amyloidosis. No previous qualitative study of the family members' experience of the disease has been published. The purpose of this phenomenological study was to understand the lived experience of family members whose nearest and dearest suffered from familial amyloidotic polyneuropathy. In-depth interviews were conducted with six family members. The analysis of the data was inspired by Colaizzi's method. Two major theme categories, difficult to accept and forced to accept, emerged from the interviews. Implications for nursing practice, such as genetic counselling and support, are discussed.

[Hereditary neural amyotrophy (HNA): clinical and molecular genetic basis]. / Hereditäre Neuralgische Amyotrophie (HNA): Klinische und molekulargenetische Befunde.

Hereditary neuralgic amyotrophy (HNA) and hereditary neuropathy with liability to pressure palsies (HNPP) are hereditary focal neuropathies. In this study we describe three families suffering from HNA. These families were examined clinically and electrophysiologically. Linkage analysis with markers from distal chromosome 17 was performed in a three-generation family. HNA could be separated from HNPP in all three families based on clinical and electrophysiological findings. HNA was characterised by recurrent episodes of painful brachial plexus lesions. In contrast to HNPP, no evidence for generalised neuropathy was found in the HNA families. Linkage analysis confirmed the HNA locus on distal chromosome 17. Additionally, we were able to refine the HNA locus to a 16 cM region on chromosome 17q24-q25.

Familial amyloidotic patients' experience of the disease and of liver transplantation.

Liver transplantation is a new treatment for familial amyloidotic polyneuropathy (FAP). No qualitative study examining these patients' experiences of the disease and the treatment has been published. The purpose of this study was to explore and describe the experience of the disease and the liver transplantation from the FAP patient's perspective. In-depth interviews with 11 liver transplant FAP patients were performed. The process of the FAP disease and a liver transplantation was found to involve the following categories: going downhill, defence and denial, a chance of surviving, the decision -- no choice, waiting powerless and uncertain, the first few steps after surgery, freed from the death sentence, still disabled, mastering up strength to recover, and the need for support and help.

Aged non-human primates: an animal model of age-associated neurodegenerative disease.

Aged non-human primates develop age-associated behavioral and brain abnormalities similar to those that occur in aged humans and, to a greater extent, in individuals with Alzheimer's disease. Declines in performance on cognitive and memory tasks begin at the monkey equivalent of late-middle life. As occurs in elderly humans, significant differences have been demonstrated in levels of performance between animals within older age groups. The brains of old monkeys show degenerative changes in neurons, abnormal axons and neurites (particularly in telencephalic areas), and deposits of amyloid in senile plaques and around blood vessels. Moreover, in some older animals, decrements occur in markers of specific neurotransmitter circuits, including the basal forebrain cholinergic system. It has been suggested that alterations in these cholinergic neurons contribute to the memory deficits that occur in older individuals. Because axotomy-induced retrograde degeneration of these neurons can be prevented by the administration of nerve growth factor, we have begun studies to determine whether administration of nerve growth factor improves performance of aged animals on memory tasks. This review describes the complementary nature of studies of non-human primates and human subjects, illustrating how these investigations can clarify factors that influence behavior and brain biology in age-associated diseases.