Significance of radio-pathological correlations: differentiating severe central nervous system infection from acute embolic infarction

We describe two educational autopsy cases of severe central nervous system (CNS) infection and septic emboli, such cases having been difficult to differentiate from acute infarctions via emergency MR imaging studies. We briefly discuss the pathology and MR findings along with radiopathological correlation.

Analysis of the adrenal gland is useful for evaluating pathology of the peripheral autonomic nervous system in lewy body disease

Lewy body disease is defined as Lewy body-related neuronal degeneration involving the nigrostriatal system, limbic-neocortical system, and peripheral autonomic nervous system (PANS). We investigated whether the adrenal gland, which is evolutionarily related to sympathetic ganglia and is routinely examined in general autopsy, could be used to assess pathology of the PANS in Lewy body disease. Brains, spinal cords, and adrenal glands from 783 consecutive autopsy cases from a general geriatric hospital were examined immunohistochemically with antiphosphorylated alpha-synuclein antibodies and routine staining. Parkinson disease (PD) with dementia and dementia with Lewy bodies (DLB) were defined using 1996 Consensus Guidelines for DLB and the secondary Lewy body-related alpha-synucleinopathy or amygdala variants using previously established criteria. Lewy body-related alpha-synucleinopathy was found in 207 (26.4%) of 783 cases, with 1 case solely in the adrenal gland. In all 18 PD cases with or without dementia and in 33 of 38 DLB cases, the adrenal gland was involved, but it was spared in all cases of amygdala variants. Our results indicate that the adrenal gland can provide useful information for evaluation of the PANS in Lewy body disease.

[Establishment of brain bank for aging research]

We have established a brain bank for the prevention and treatment of aging-related movement and cognitive disturbances, as a joint project between a rural care hospital and a research institute. The resources of the bank are to be used for collaborative studies approved by the bank's committee. The collaborative investigators should also be qualified by the institute to conduct the research jointly. The collaborative studies require authorization by the institutional review board (IRB) of the institute, the hospital and each facility involved in collaborative studies. The bank continues to have the responsibility for the resources, after the transfer of the resources to the facilities of collaborative investigators, pursuant to Article 18 of the Cadaver Autopsy and Preservation Act Thus, the status of resource utilization and outcomes from their use in studies will be monitored periodically (every 6 months). We shared the philosophy with the brain banks in the United States that the resources of the bank, donated on the basis of a charitable spirit, belong to the public domain and are regarded as public resources to be used to contribute to promoting public welfare.

Association of estrogen receptor alpha gene polymorphisms with neurofibrillary tangles

Estrogen receptor alpha (ERalpha) may be implicated in the pathogenesis of Alzheimer's disease (AD). The aim of this study was to clarify the association between ERalpha gene polymorphisms and AD-related pathologic changes. The staging of neurofibrillary tangles (NFT) and senile plaques (SP) was performed according to the method by Braak and Braak and two polymorphisms, PvuII (P or p) and XbaI (X or x), of the ERalpha gene were typed in 551 Japanese cadavers (294 men and 257 women; mean age, 80.8 years). Distributions of the NFT and SP stages significantly correlated with age (NFT: r = 0.306, p < 0.0001; SP: r = 0.237, p < 0.0001) and were significantly higher in patients with the apolipoprotein E epsilon4 allele (p < 0.0001). Possession of the P allele showed a trend to be associated with a more serious NFT stage, but had no relationship with the SP stage. In men, a significant association between PvuII polymorphism and the NFT stage (p = 0.002) was found, revealing a gene- dose effect of the P allele. Similar results were obtained in the men without the epsilon4 allele (p = 0.011). Multiple regression analyses demonstrated that age was the strongest determinant of the NFT stage, possession of the epsilon4 allele was the next strongest, and PvuII polymorphism was the third strongest (p < 0.0001, R(2) = 0.144). The XbaI polymorphism did affect neither the NFT stage nor the SP stage. In conclusion, the PvuII polymorphism of the ERalpha gene is associated with Braak NFT stages and possession of the P allele may act as a risk factor for AD in Japanese men, especially in those without the epsilon4 allele.

[Parkinson disease with dementia--responsible locus for dementia]

Responsible locus for dementia in Parkinson disease (PD) was investigated. Serial 1,395 autopsy cases were studied for the combined pathology of PD and Alzheimer disease (AD). Following the one-year rule by the first Consensus Guidelines, definite AD pathology was quite rare in PD with dementia (PDD) but common in dementia with Lewy bodies (DLB) . Plaque-dominant senile changes apparently enhanced neocortical Lewy-body pathology in both the conditions. About the hypometabolism in the visual cortex of PDD, a 66-year old man presented with fluctuation in hallucination commensurate with fluctuating hypometabolism. Considering the paucity in pathological changes of the visual cortex, this hypometabolism may represent functional impairment in the fiber connection. Comparative pathological studies with PD and PDD were carried out. Only one case of a 48-year-old woman, who unexpectedly died of heart failure, was free from cognitive decline, and did not show limbic and neocortical involvement. Another case of a 75-year old man with MCI presented with the similar pathology. All other cases showed clinical documentation of cognitive impairment and limbic and neocortical pathological involvement. Thus, the combination of prospective clinical and radiological studies and retrospective pathological studies (dynamic neuropathology) may be essential to investigate a role of the basal-forebrain cholinergic system.

Cerebrospinal fluid tau in dementia disorders: a large scale multicenter study by a Japanese study group

A large scale multicenter study of cerebrospinal fluid (CSF) tau levels was conducted to determine the cut-off value, sensitivity and specificity for clinical usage as a biomarker of Alzheimer's disease (AD). Its use for early and differential diagnosis and the factors that increase CSF tau levels were also examined. CSF samples from a total of 1,031 subjects including 366 patients with AD, 168 patients with non-Alzheimer type dementia (NA), 316 patients with non-dementia neurological diseases (ND) and 181 normal controls (NC) were measured using ELISA for tau. The cut-off value of tau, 375 pg/ml, showed 59.1% sensitivity and 89.5% specificity for diagnosis of AD compared with the other groups. The tau levels were increased from the early to late stages of AD. Elevation of CSF tau in the non-tauopathy and tauopathy dementia groups, chronic and acute damage to the cerebrum, and meningeal disturbance were other factors that required attention for clinical practice. Measurement of CSF tau was useful as a biomarker for early and differential diagnosis of AD.

[Antihypertensive therapy in patients with stroke]

Most patients with acute ischemic stroke do not need antihypertensive therapy, because the rapid lowering of blood pressure (BP) may reduce cerebral blood flow due to impaired cerebral autoregulation. In patients with severe hypertension, or associated with other complications (hemorrhagic transformation, myocardial infarction, renal failure or dissection of the aorta), antihypertensive therapy should be done cautiously. In chronic phase, the optimal BP level for the prevention of stroke recurrence remains unclear. The presence of the J-curve phenomenon is still controversial. The several large scale trials are now in progress to determine the optimal BP level for the secondary prevention in stroke patients.

[Quantitative evaluation of the burden of those giving home care for senile dementia of Alzheimer type subjects using the burnout scale of pines]

We quantitatively measured the physical and psychological burden of caregivers of 25 patients with senile dementia of Alzheimer type (SDAT). The Barthel Index (BADL, full score: 20 points) and the caregiver burden in terms of physical symptoms correlated well (r = -0.964, p < 0.001), as did the degree of abnormal behavior and caregiver burden in terms of psychological symptoms (r = 0.946, p < 0.001). The correlation with the burnout scale (BOS) of Pines was best when both factors of psychological and physical symptoms were included. The correlation between BOS and the caregiver burden in terms of both physical and psychological symptoms was r = 0.874, p < 0.001, and the correlation between BOS and "the degree of abnormal behavior" +(20- "BADL") was r = 0.853, p < 0.001. The burden in terms of physical symptoms increased as the BADL score decreased, but the burden in terms of psychological symptoms increased initially and decreased in the last phase of the disease. We conclude that the BOS score of SDAT caregivers was stable in the initial phase, then increased rapidly, thereafter preserved high, and dropped rapidly as the BADL score decreased.

NdWFamide: a novel excitatory peptide involved in cardiovascular regulation of Aplysia

Although diverse peptides are known to affect invertebrate cardiac activity, the peptidergic regulation of the cardiovascular system of Aplysia is still poorly understood. Asn-D-Trp-Phe-NH(2) (NdWFamide) is a recently purified cardioactive peptide in Aplysia. Pharmacological experiments showed that NdWFamide was one of the most potent cardioexcitatory peptides among the known endogenous cardioactive peptides in Aplysia. NdWFamide-immunopositive neuronal processes were abundant in the cardiovascular region of Aplysia, and many of them originated from neurosecretory cells in the abdominal ganglion (R3-R13 cells). The data suggest that NdWFamide is a cardioexcitatory peptide utilized by R3-R13 cells of Aplysia.

The effects of short-term blood pressure variability and nighttime blood pressure levels on cognitive function

We investigated the relationship between 24-h blood pressure (BP) and cognitive function. We performed the Hasegawa Dementia Scale Revised (HDSR), the Mini-Mental State Examination (MMSE), and the Raven's Coloured Progressive Matrices Test (RCPM) in 88 subjects (71+/-9 years) with no history of stroke. Ambulatory BP was non-invasively measured using a TM2421 for 24 h in all patients. Whereas 90% of the scores converged into a narrow range between 25 and 30 points in the HDSR and the MMSE tests, the RCPM score was widely distributed, ranging from 9 to 36 points. The subjects were therefore divided into three groups of > or =25, 26-30, and 31-36 according to their RCPM scores. Subjects with lower scores were significantly associated with increased short-term BP variability during the daytime (p<0.05) and had a tendency toward higher nighttime SBP (p=0.05) compared with those with higher scores. Increased short-term variability of daytime BP and high nighttime systolic BP were associated with cognitive impairment as assessed by the RCPM. The RCPM, which can assess the capacity for judgment through visual information processing, may detect earlier stages of cognitive impairment related to high BP. To prevent a deterioration of cognitive function, strict control of nighttime BP and suppression of short-term BP variability are thus necessary.

Tri-n-butyltin-induced change in cellular level of glutathione in rat thymocytes: a flow cytometric study

Since some of organotins, accumulated in edible mollusks of aquatic environments, exert a variety of toxic actions on experimental animals, it causes concern for the health of humans. We examined the effects of tri-n-butyltin chloride (TBT) and other organotins (triethyltin chloride, trimethyltin chloride, triphenyltin chloride and tetrabutyltin) on cellular content of glutathione (GSH) in rat thymocytes using a flow cytometer to further characterize the toxicity of TBT. When the cells were incubated with TBT at concentrations of 3 nM or more for 15 min, the cellular content of GSH dose-dependently decreased. However, it completely or partly recovered until 180 min even in the continued presence of TBT. This recovery was temperature-sensitive, suggesting an involvement of metabolic process. The efficacy of TBT to decrease the cellular content of GSH was greater than those of other organotins. Results suggest that TBT and some organotins at environmentally relevant (nanomolar) concentrations significantly reduce the cellular content of GSH, suggesting that they increase the vulnerability to some biological and chemical insults.

Impairment and restoration of the endothelial blood-brain barrier in the rat cerebral infarction model assessed by expression of endothelial barrier antigen immunoreactivity

Endothelial barrier antigen (EBA) can be used to detect the blood-brain barrier in the central nervous system of rats. This study investigated the temporal profile of antigen expression in cerebral vessels after infarction and assessed the relationship between re-establishment of this antigen in newly formed vessels and astrocytes around these vessels. Rats were subjected to cerebral ischemia for 2 h by the intraluminal thread method, then killed after 1, 3, 7, 14 and 28 days. Perfusion-fixed paraffin-embedded brains were immunostained for detection of EBA and glial fibrillary acidic protein (GFAP) by the streptavidin-biotin-peroxidase complex method. EBA immunostaining in vessels in the infarcted lesion was reduced at day 1 and had almost disappeared by day 3. Newly formed vessels were found from day 3, but were not stained at day 7. However, these new vessels were weakly stained at day 14 and definitely stained at day 28. GFAP immunostaining was completely negative around these proliferating vessels. The temporal profile of disappearance and re-expression of EBA in cerebral infarcted lesion may be associated with aggravation and improvement of brain edema, although barrier permeability was not explored in this study. The expression of this antigen has no relationship to the formation of astrocyte/endothelial contacts.

Exposure of rat thymocytes to hydrogen peroxide increases annexin V binding to membranes: inhibitory actions of deferoxamine and quercetin

Effects of hydrogen peroxide (H(2)O(2)) on rat thymocytes were examined, using a flow cytometer and three fluorescent probes, annexin V-fluorescein isothiocyanate (annexin V-FITC) for detecting phosphatidylserine expressed on the membrane surface, ethidium bromide for estimating dead cells, and fluo-3-acetoxymethyl ester (fluo-3-AM) for monitoring changes in intracellular Ca(2+) concentration ([Ca(2+)](i)), to characterize H(2)O(2)-induced cytotoxicity. Exposure to H(2)O(2) (30 microM or more) increased the number of annexin V-positive live cells dose- and time-dependently while the number of dead cells increased at concentrations of 1 mM or more. H(2)O(2) (30 microM or more) increased [Ca(2+)](i) in a dose-dependent manner. Threshold concentration of H(2)O(2) to increase [Ca(2+)](i) was similar to that to increase annexin V binding to membranes. The H(2)O(2)-induced change in cell membranes was attenuated under Ca(2+)-free conditions. Therefore, it is likely that Ca(2+) is involved in the H(2)O(2)-induced cytotoxicity. Deferoxamine was effective to protect the cells suffering from H(2)O(2)-induced oxidative stress, suggesting a contribution of hydroxyl radicals generated by the Fenton reaction. Quercetin also exerted a potent protective action on cells suffering from H(2)O(2)-induced oxidative stress. The results indicate that the exposure of rat thymocytes to H(2)O(2) at micromolar concentrations increases annexin V binding to cell membranes in a Ca(2+)-dependent manner, suggesting the possibility that the oxidative stress caused by H(2)O(2) (and/or hydroxyl radicals) induces apoptosis via increasing [Ca(2+)](i).