Senile dementia of Lewy body type. A clinically and neuropathologically distinct form of Lewy body dementia in the elderly

A dementing syndrome has been identified in a group of psychiatric cases aged 71-90 years, presenting initially with a subacute/acute confusional state, often fluctuating and associated with visual hallucinations and behavioural disturbances. Clinically, these cases did not meet criteria for a diagnosis of Alzheimer's disease, and many were assigned to the multiinfarct dementia group, although no significant ischaemic lesions were evident at autopsy. Mild extrapyramidal features were apparent in a number of cases but the characteristic clinical triad of Parkinson's disease, i.e., tremor, rigidity, and akinesia, was absent. Detailed neuropathological examination revealed Lewy body formation and selective neuronal loss in brain stem and other subcortical nuclei, accompanied by Lewy body formation in neo- and limbic cortex, at densities well below those previously reported in diffuse Lewy body disease. A variable degree of senile degenerative change was present; numerous senile plaques and minimal neurofibrillary tangles in most cases. Neither the clinical nor the neuropathological features of this group are typical of Parkinson's or Alzheimer's disease, but suggest a distinct neurodegenerative disorder, part of the Lewy body disease spectrum, in which mental symptoms predominate over motor disabilities and lead to eventual psychogeriatric hospital admission. In a sequential series of autopsies conducted on clinically assessed demented patients, neuropathological analysis has indicated that such cases may comprise up to 20% of a hospitalized population of demented old people over the age of 70 years, an observation clearly relevant to the diagnosis and management of dementia in the elderly.

The numbers of limb motor neurons in the human lumbosacral cord throughout life

Forty-seven spinal cords from subjects between 13 and 95 years of age have been examined; in the majority death occurred suddenly or rapidly from a state of previous good health. The limb motor neurons in the lumbospinal segments have been estimated by counting nucleoli in characeteristic cells in every fifth group of 10 serial sections from the entire lumbosacral cord. No evidence exists of loss of motor neurons up to the age of 60 years, but beyond that age, although individual counts vary considerably, there is increasing evidence of a diminishing motor neuron pupulation; above 60 years, several cases showed motor neuron counts of only 50% of the counts in early adult life or middle age. Cell loss appeared to be uniform throughout all the segments and was unaccompanied by any other striking morphological change.

Cell loss in the locus coeruleus in senile dementia of Alzheimer type

Sample counts of the pigmented cells of the locus coeruleus (LC) were performed in 10 middle-aged and 15 old people considered to be intellectually well preserved and in 15 cases of senile dementia of Alzheimer type (SDAT). Evidence of a gradual loss of neurons from early middle to old age was found in the control group. In the cases of SDAT 7 counts were within the lower range for the controls but 8 had fewer neurons than any control recorded and the mean count for all the SDAT cases was significantly less than that of the older controls. Some evidence exists that the more severe cases of SDAT in terms of neocortical plaque formation have the greatest loss of LC neurons.

Environmental factors and cancer of the colon and breast

The correlation between cancer of the breast, colon and stomach dietary factors, and various indicators of standard of living was examined. Cancer of the breast and colon was highly correlated with fat and animal protein.

Pathological changes in the nucleus of Meynert in Alzheimer's and Parkinson's diseases

Combined neuropathological and neurochemical assessment of the nucleus of Meynert in senile dementia of Alzheimer type (SDAT) have demonstrated that the cholinergic biochemical activity, choline acetyltransferase, is more extensively reduced in the nucleus (over 90%) than the loss of putative cholinergic perikarya (35%). Acetylcholinesterase histochemical activity was however substantially retained in individual neurones in the nucleus although virtually absent from the neocortex in SDAT. These abnormalities are consistent with a primary degeneration of cholinergic axons projecting to the cortex and secondary loss of perikarya from the subcortical nucleus. In contrast, preliminary observations on cases of Parkinson's disease suggest that the neuronal loss from the nucleus of Meynert may be greater in this disease than in SDAT, and previous studies have not consistently demonstrated a reduction in cortical choline acetyltransferase activities in Parkinson's disease. These observations, together with major differences in the neuropathology of the nucleus in SDAT and Parkinson's disease (neurofibrillary tangle and Lewy body formation, respectively) suggest that the involvement of the cholinergic system may differ in the two disease processes.

Alteration in nicotine binding sites in Parkinson's disease, Lewy body dementia and Alzheimer's disease: possible index of early neuropathology

High-affinity nicotine binding, considered to primarily reflect the presence of CNS alpha 4 beta 2 nicotinic receptor subunits, was examined autoradiographically in brain regions most severely affected by Alzheimer and Parkinson types of pathology. In the midbrain, the high density of binding associated with the pars compacta of the substantia nigra was extensively reduced (65-75%, particularly in the lateral portion) in both Lewy body dementia and Parkinson's disease. Since loss of dopaminergic neurons in Lewy body dementia was only moderate (40%), loss or down-regulation of the nicotinic receptor may precede degeneration of dopaminergic neurons in this region. In the dorsolateral tegmentum, where diffuse cholinergic perikarya are located, nicotine binding was highly significantly decreased in both Lewy body dementia and Parkinson's disease with almost no overlap between the normal and disease groups, indicative of a major pathological involvement in or around the pedunculopontine cholinergic neurons. In the hippocampus, binding was decreased around the granular layer in Lewy body dementia and Alzheimer's disease, although unchanged in the stratum lacunosum moleculare, where binding was relatively higher. Dense bands of receptor binding in the presubiculum and parahippocampal gyrus--areas of highest binding in human cortex--were diminished in Alzheimer's disease but not Lewy body dementia. In temporal neocortex there were reductions in Alzheimer's disease throughout the cortical layers but in Lewy body dementia only in lower layers, in which Lewy bodies are concentrated. Abnormalities of the nicotinic receptor in the diseases examined appear to be closely associated with primary histopathological changes: dopaminergic cell loss in Parkinson's disease and Lewy body dementia, amyloid plaques and tangles in subicular and entorhinal areas in Alzheimer's disease. Loss or down-regulation of the receptor may precede neurodegeneration.

Extensive loss of choline acetyltransferase activity is not reflected by neuronal loss in the nucleus of Meynert in Alzheimer's disease

Choline acetyltransferase activity in discrete tissue punches from the nucleus of Meynert and in tissue from the temporal cortex was reduced by at least 90% and 75%, respectively, in 5 out of 6 elderly cases of Alzheimer's disease compared with 5 normal cases. In contrast, estimates of neurone density in these same cases revealed that there was only, on average, a 33% neurone loss in the nucleus of Meynert in Alzheimer's disease. These observations suggest that a key pathological change in Alzheimer's disease may be the 'down regulation' of transmitter-specific enzyme production in cholinergic neurones, and that neurone loss itself may be a secondary feature of the disease.

Cholinergic transmitter and neurotrophic activities in Lewy body dementia: similarity to Parkinson's and distinction from Alzheimer disease

Senile dementia of Lewy body type or Lewy body dementia (LBD), characterized neuropathologically by the presence of Lewy bodies in the brainstem and cortex, and in most cases neocortical senile plaques (but few or no tangles), bears a closer resemblance to Parkinson's (PD) than to Alzheimer disease (AD) in its cholinergic neurochemical pathology. Thus, reductions in the biochemical activity of choline acetyltransferase were generally more extensive in neo- as opposed to archicortical regions in LBD (especially hallucinating cases) and in PD, whereas muscarinic receptor binding was significantly increased in LBD and PD but not in AD. Nerve growth factor receptor (P75) assessed immunocytochemically in the archicortex were decreased in PD and, to a lesser extent, in LBD in conjunction with reductions of neuronal numbers in the nucleus of Meynert (Ch4), but were relatively spared in AD. These observations indicate that although AD is primarily associated with dysfunction of cholinergic axonal input to the cortex, LBD and PD are more likely to involve degeneration of the basal forebrain cholinergic system. Relevance of the findings in terms of aetiopathology and cholinergic treatment strategies is discussed.

Topography, extent, and clinical relevance of neurochemical deficits in dementia of Lewy body type, Parkinson's disease, and Alzheimer's disease

Cholinergic and monoaminergic (dopaminergic and serotonergic) activities have been examined in postmortem brain tissue in senile dementia of Lewy body type, Parkinson's disease, and Alzheimer's disease. Quantitative data suggest that although extrapyramidal symptoms relate to striatal levels of dopamine, cognitive impairment is most closely associated with cholinergic (but not monoaminergic) deficits in temporal and archicortical areas. Hallucinations, which are most frequent in Lewy body dementia, appear to be related to an extensive cholinergic deficit in temporal neocortex and the resulting imbalance between decreased cholinergic and relatively preserved serotonergic activities. Topographic analyses such as these including consideration of quantitative "threshold" effects, may be relevant to the future anatomic focus of neurochemical investigations in dementia and to the development of appropriate experimental models.

Quantitative neuropathological study of Alzheimer-type pathology in the hippocampus: comparison of senile dementia of Alzheimer type, senile dementia of Lewy body type, Parkinson's disease and non-demented elderly control patients

A Lewy body dementing syndrome in the elderly has been recently described and designated senile dementia of Lewy body type (SDLT) on the basis of a distinct clinicopathological profile. The pathological changes seen in SDLT include the presence of cortical Lewy bodies (LB) frequently, but not invariably, associated with senile plaque (SP) formation. Whilst neocortical neurofibrillary tangles (NFT) are sparse or absent, a proportion of these cases show involvement of the temporal archicortex by lesions comprising Alzheimer-type pathology (ATP, i.e. NFT, SP and granulovacuolar degeneration [GVD]). Thus the relationship between SDLT and senile dementia of Alzheimer type (SDAT) is complex and controversial. In this study quantitative neuropathology was used to compare the intensity and distribution of ATP in the hippocampus and entorhinal cortex of 53 patients from 3 disease groups (SDLT, SDAT, Parkinson's disease (PD)) and a group of neurologically and mentally normal elderly control patients. For most brain areas examined the extent of ATP between the patient groups followed the trend SDAT greater than SDLT greater than PD greater than control. Statistical comparison of these groups revealed significant differences between the mean densities of NFT, SP and GVD although individual cases showed considerable variability. These results confirm additional pathological differences between SDAT and SDLT regarding the intensity of involvement of the temporal archicortex by ATP. Many patients with Lewy body disorders (LBdis) show a predisposition to develop ATP albeit in a more restricted distribution (e.g. low or absent neocortical NFT) and at lower densities than is found in SDAT. Some cases of SDLT show minimal SP and NFT formation in both neocortex and archicortex supporting previously published data distinguishing this group from Alzheimer's disease.

Use of Gianturco self-expandable stents in the tracheobronchial tree

Gianturco self-expandable stents were used successfully in the management of 5 patients with tracheobronchial pathology. Placement was performed under endoscopic and fluoroscopic guidance. None of the patients has experienced complications secondary to the stent placement, and in all of them the clinical problems resolved satisfactorily. Longer follow-up is required to determine the place of tracheobronchial stenting in patients with respiratory compromise.

Lewy body prevalence in the aging brain: relationship to neuropsychiatric disorders, Alzheimer-type pathology and catecholaminergic nuclei

In a survey to determine the occurrence of Levy bodies in the elderly, the prevalence rate of Lewy body formation was found to be critically dependent on the psychiatric status of control cases. In 131 controls between 51 and 100 years screened to exclude psychiatric and neurological disorders, the Lewy body prevalence rate was 2.3%, but inclusion of cases with psychiatric disorders other than Alzheimer's disease increased the prevalence rate to 9%. An age-related decline in substantia nigra and locus coeruleus neuron numbers was observed in the control group. Brain stem Lewy body formation (found in 3 cases) was not necessarily linked with neuron loss in substantia nigra, though in two of the cases significant locus coeruleus neuron loss was observed. Within the control group, there was no obvious relationship of Lewy body formation to the extent of Alzheimer-type pathology. These findings are compatible with the disease specificity of Lewy bodies and suggest that Lewy body disorders have a relatively short preclinical phase in which Lewy body formation may precede both locus coeruleus and substantia nigra neuron loss. The increase of Lewy body positive cases found when individuals with psychiatric disorders are included in the population surveyed supports the emerging concept of a spectrum of Lewy body diseases ranging from purely psychiatric disorders through combined psychoneurological or neuropsychiatric symptoms, to the classically described neurological disorders of Parkinson's disease.

Effect of dietary catechin and vitamin E on aortic fatty streak accumulation in hypercholesterolemic hamsters

Male golden Syrian hamsters were fed for 16 weeks on a hypercholesterolemic diet containing, per kg, 150 g of lipids (90 g butterfat, 35 g vitamin E-stripped corn oil and 25 g fish oil), 2 g cholesterol and either 3 IU vitamin E (3 IU E), 3 IU vitamin E and 200 mg catechin hydrate (3 IU E-200 Cat) or 30 IU vitamin E (30 IU E). More fatty streaks, measured by Oil Red O staining, were deposited in aortas of hamsters fed 3 IU E than in those fed either 3 IU E-200 Cat or 30 IU E. Lipid staining increased with plasma low-density lipoprotein cholesterol (LDL-C) in all animals. At the same concentration of LDL-C, animals fed either 3 IU E-200 Cat or 30 IU E developed less fatty streaks than those fed 3 IU E. Plasma LDL-C and total cholesterol were highest in hamsters fed 3 IU E and LDL-C and total cholesterol in animals fed 3 IU-200 Cat were not different from those fed either 3 IU E or 30 IU E. This study showed the importance of circulating plasma LDL-C on atherogenesis and the inhibitory effect on this process of both dietary vitamin E and catechin.

Seroprevalence of 2009 pandemic influenza A(H1N1) virus in Australian blood donors, October - December 2009

Assessment of the severity of disease due to the 2009 pandemic influenza A(H1N1) in Australian states and territories has been hampered by the absence of denominator data on population exposure. We compared antibody reactivity to the pandemic virus using haemagglutination inhibition assays performed on plasma specimens taken from healthy adult blood donors (older than 16 years) before and after the influenza pandemic that occurred during the southern hemisphere winter. Pre-influenza season samples (April – May 2009, n=496) were taken from donation collection centres in North Queensland (in Cairns and Townsville); post-outbreak specimens (October – November 2009, n=779) were from donors at seven centres in five states. Using a threshold antibody titre of 40 as a marker of recent infection, we observed an increase in the influenza-seropositive proportion of donors from 12% to 22%, not dissimilar to recent reports of influenza A(H1N1)-specific immunity in adults from the United Kingdom. No significant differences in seroprevalence were observed between Australian states, although the ability to detect minor variations was limited by the sample size. On the basis of these figures and national reporting data, we estimate that approximately 0.23% of all individuals in Australia exposed to the pandemic virus required hospitalisation and 0.01% died. The low seroprevalence reported here suggests that some degree of prior immunity to the virus, perhaps mediated by broadly reactive T-cell responses to conserved influenza viral antigens, limited transmission among adults and thus constrained the pandemic in Australia.

Reduced oviposition of Boophilus microplus feeding on sheep vaccinated with vitellin

The most abundant protein present in Boophilus microplus eggs, vitellin, was isolated and purified as a non-covalent complex of six glyco-polypeptides of Mr 44-107kDa. The protein complex bound haem. Immuno-blots demonstrated that antibodies raised to vitellin recognised a 200kDa polypeptide in the haemolymph of adult female ticks. This is consistent with the general proposal that in arthropods vitellin is derived by proteolytic processing from a large precursor protein, vitellogenin. In parallel with this study, an 80kDa glycoprotein (GP80) was independently purified from larvae of B. microplus using efficacy in vaccination trials as an assay. Antibodies to GP80 also recognised a 200kDa protein in the haemolymph of ticks and a major 87kDa polypeptide present in the vitellin complex. Conversely, antibodies to purified vitellin recognised GP80. The amino-terminal amino acid sequences of the 87kDa vitellin polypeptide and GP80 were identical for at least the first 11 residues and internal peptide sequences from both polypeptides were co-located in a single but incomplete deduced amino sequence of B. microplus vitellogenin. Thus, GP80 is a processed product from vitellogenin and highly related to but not completely identical with the 87kDa vitellin polypeptide. Vaccination trials in the model host sheep were performed with purified vitellin and GP80. Sheep vaccinated with either purified vitellin or GP80 returned significantly reduced numbers of engorged female ticks with decreased weights and reduced oviposition. In contrast, sheep vaccinated with recombinant hexahis-GP80, which was incorrectly folded and not glycosylated showed no significant effects on ticks. It was concluded that vitellin and GP80 could induce immune responses that partially protect sheep from the tick, B. microplus. However, critical protective epitopes are associated with the folding of the protein and/or the oligosaccharides attached to it.

The 42-kilodalton rhoptry-associated protein of Plasmodium falciparum

The gene coding for a 42-kDa rhoptry protein of Plasmodium falciparum has been cloned. On the basis of prior monkey vaccination studies, this protein is regarded as an important vaccine candidate, but its identity has been the subject of considerable uncertainty. Analysis of the cloned sequence shows that it is a basic, hydrophobic protein, without repetitive elements, unrelated to any of the previously postulated gene products and shows minimal sequence diversity. The availability of the corresponding recombinant protein will enable studies of its efficacy in human vaccine trials to be undertaken.

Relief of bileduct obstruction by the percutaneous transhepatic insertion of an endoprosthesis

Benign and malignant biliary strictures can be treated by the percutaneous transhepatic insertion of an endoprosthesis. We report the use of this technique in 44 patients, with a detailed description of the procedure. Insertion was successful in 41, three of whom later had elective surgery, and one, emergency laparotomy for biliary peritonitis. This patient died post-operatively. Cholestasis was relieved in 31 of the remaining 37 patients. Complications occurred in four. Twelve patients, all with malignant disease, died within 30 days of the procedure. The percutaneous insertion of a biliary endoprosthesis is a valuable alternative to surgery in selected patients. Complications can occur, and the prognosis depends on the nature of the underlying disease.

Detection of Lewy bodies in Trisomy 21 (Down's syndrome)

The presence of cortical senile plaques and neurofibrillary tangles sufficient to warrant a neuropathological diagnosis of Alzheimer's disease is well established in middle-aged individuals with Trisomy 21 (Down's syndrome). In contrast a relationship between Down's syndrome and Lewy bodies, one of the major neuropathological features of Parkinson's disease, has not been previously reported. In a clinico-neuropathological survey of 23 cases of Down's Syndrome, two patients, aged 50 and 56 years respectively, were found to have Lewy body formation in the substantia nigra in addition to cortical Alzheimer-type pathology. Neither case showed significant substantia nigra neuron loss although locus coeruleus loss was present in both. Since substantia nigra Lewy bodies are a characteristic neurohistological feature of idiopathic Parkinson's disease, their occurrence in cases of Down's syndrome with evidence of Alzheimer-type pathology supports an aetiopathological connection between Parkinson's disease, Alzheimer's disease, and Down's syndrome; and suggests that common pathogenic mechanisms may underlie aspects of neuronal degeneration in these three disorders, some of which may relate to aberrant chromosome 21 expression.

Monoaminergic activities in Lewy body dementia: relation to hallucinosis and extrapyramidal features

Serotonergic (5-HT) and dopaminergic activities have been examined in Lewy Body Dementia (LBD) and compared with Parkinson's disease (PD) and Alzheimer's disease (AD). In the neocortex the LBD subgroup experiencing hallucinations was distinguished from the other categories by an increase in the 5HIAA:5HT ratio measured in frontal cortex and by the serotonergic (5-HIAA or 5-HIAA:5-HT): cholinergic (choline acetyltransferase) ratio in frontal and temporal cortex. In the neostriatum (caudate nucleus), loss of dopamine and increased HVA:dopamine ratio correlated with the reduction in substantia nigra neurons in LBD but not PD, despite the greater loss of neurones and dopamine and the higher dopamine turnover ratio in PD. LBD patients experiencing severe Parkinsonism as a result of neuroleptic treatment tended to have lower neuron counts, in combination with higher turnover ratios, than the remainder. Qualitative differences between LBD and PD included decreased cortical 5-HT turnover in PD compared with the increase in LBD. There were no significant changes in any parameter in AD, with the exception of a reduction in temporal cortex 5HIAA. The results suggest that although the neurochemical pathology of LBD and PD involves similar systems, the nature of the derangements differs sufficiently between the diseases to account for differences in symptomatology.

Synchronization of dynamical hypernetworks: dimensionality reduction through simultaneous block-diagonalization of matrices

We present a general framework to study stability of the synchronous solution for a hypernetwork of coupled dynamical systems. We are able to reduce the dimensionality of the problem by using simultaneous block diagonalization of matrices. We obtain necessary and sufficient conditions for stability of the synchronous solution in terms of a set of lower-dimensional problems and test the predictions of our low-dimensional analysis through numerical simulations. Under certain conditions, this technique may yield a substantial reduction of the dimensionality of the problem. For example, for a class of dynamical hypernetworks analyzed in the paper, we discover that arbitrarily large networks can be reduced to a collection of subsystems of dimensionality no more than 2. We apply our reduction technique to a number of different examples, including the class of undirected unweighted hypermotifs with 3 nodes.

Interrater reliability of the Antipsychotic Non-Neurological Side-Effects Rating Scale measured in patients treated with clozapine

The Antipsychotic Non-Neurological Side-Effects Rating Scale (ANNSERS) was developed to provide a comprehensive measure for rating non-neurological adverse drug reactions (ADRs) to antipsychotics. Although there were already available measures that adequately rated specific non-neurological ADRs, such as sexual side effects, a need was identified for a scale that comprehensively rated the full range of non-neurological ADRs commonly seen across the spectrum of first and second generation antipsychotic drugs, including metabolic and autonomic ADRs. This article reports on work to establish the interrater reliability of an early version and a later, more comprehensive version of the ANNSERS (versions 1 and 2, v1 and v2, respectively). The measures were administered in London centres to patients treated with clozapine. Trained clinicians rated the patients simultaneously and independently. Interrater reliability on the scores was calculated using the kappa coefficient method. The results (mean kappa coefficients of 0.77 and 0.72, respectively) indicate that substantial interrater reliability was achieved for both versions. Items for which the main basis for rating was laboratory investigations rather than patient interview were largely excluded from this study, and kappas were also not calculated for items with a low frequency (less than 10%) of endorsement. Samples of patients on other antipsychotics would be required to reliably calculate kappa coefficients for these items. In conclusion, the ANNSERS represents a clinically applicable research innovation, with good interrater reliability on clinician judged items, which is now available for the comprehensive assessment of non-neurological ADRs to antipsychotics, to aid the processes of clinical audit, research and drug discovery.