PubMed Health⌕ Search

Biomedical subjects

Koji Hori

Publications and source records attributed to Koji Hori.

9 recordsLinked to original sources

Ubiquitin-positive frontotemporal lobar degeneration presenting with progressive Gogi (word-meaning) aphasia. A neuropsychological, radiological and pathological evaluation of a Japanese semantic dementia patient.

A patient with progressive anomia and alexia with agraphia for kanji (Japanese morphograms) is described. The patient showed a deficit in single-word comprehension and on-reading (a type of reading that conveys phonetic value) dominance in kanji reading, i.e. on-preceding (pronouncing first with on-reading, irrespective of its preferred reading) and kun-deletion (inability to recall and recognize kun-reading [another type of reading that conveys meaning]) when reading a single-character kanji. These features were due to loss of lexico-semantic information and thus the patient was regarded as having progressive Gogi (word-meaning) aphasia by Imura, a Japanese manifestation of semantic dementia. Macroscopically, neuropathological examination disclosed atrophy of the left frontotemporal lobe with accentuation in the anterior portion of the temporal lobe. Histologically, there was neuronal loss in the cerebral cortex, hippocampus, parahippocampal gyrus, amygdala, caudate nucleus, and putamen. Ubiquitin-immunoreactive neuronal inclusions were present in the hippocampal dentate granular cells. This case demonstrates that progressive Gogi aphasia is semiologically identical to semantic dementia, and our patient clinicopathologically resembled those of Rossor et al. [Rossor, M.N., Revesz, T., Lantos, P.L., Warrington, E.K. Semantic dementia with ubiquitin-positive tau-negative inclusion bodies. Brain 2000; 123: 267-76.] and Hodges et al. [Hodges, J.R., Davies, R.R., Xuereb, J.H., Casey, B., Broe, M., Bak, T.H., et al. Clinicopathological correlates in frontotemporal dementia. Ann Neurol 2004; 56: 399-406.].

Aged↗

Pathological heterogeneity of the precentral gyrus in Pick's disease: a study of 16 autopsy cases.

This report concerns the upper motor neuron involvement in 16 autopsy cases of Pick disease with Pick bodies, including 11 cases reported by us previously. Prominent, circumscribed atrophy of the precentral gyrus, conspicuously in the lower portion, was noted in one case. Loss of Betz cells and astrocytosis of the precentral gyrus layer V were encountered in 15 cases (94%) and eight cases (50%), respectively. Appearance of Pick bodies and ballooned neurons in the precentral gyrus layer V was confirmed in seven cases (44%). Degeneration of the pyramidal tract in the medulla oblongata was noted in all 15 cases in which this structure was examined. Pyramidal signs were observed in four (67%) of the six cases that were neurologically sufficiently examined: hyperreflexia in four cases (67%), spasticity in one case (17%). Babinski sign was not encountered in any of the six cases. In all four cases having pyramidal signs, degeneration of the pyramidal tract was observed. In contrast, two cases having degeneration of the pyramidal tract did not develop pyramidal signs. In Pick's disease with Pick bodies, obvious involvement of the precentral gyrus and pyramidal tract was not previously noticed. Furthermore, we suggest that pyramidal signs in Pick's disease with Pick bodies have been underestimated.

Aged↗

Perceptual grouping in pigeons.

Animal studies reveal that many species perceive partially occluded objects in the same way as do humans. Pigeons have been a notable exception. We re-investigated this anomaly of pigeon perception using a different approach from previous studies. With our method, we show that pigeons perceive occluded objects in the same manner as do other species. In addition, we report that pigeons can recognize perceptually transparent surfaces when the effect is induced by the same perceptual mechanisms as occlusion. These results give behavioral evidence that the perception of both occlusion and transparency is a common visual function shared by pigeons and humans, despite the structural differences between their visual systems.

Animals↗

First episodes of behavioral symptoms in Alzheimer's disease patients at age 90 and over, and early-onset Alzheimer's disease: comparison with senile dementia of Alzheimer's type.

We evaluated dementia symptoms to clarify the character of dementia with Alzheimer's disease (AD) observed in the oldest old patients and that of dementia with early-onset AD. Subjects were consecutive AD inpatients admitted for the first time at age of 90 years and over because of behavioral symptoms (demented nonagenarian group: D90G; n=18) and those with 24 consecutive inpatients with AD with early-onset (EOG). The Gottfries, Brane and Steen's scale and the Dementia Behavior Disturbance scale were used to evaluate the symptoms and troublesome behaviors. The scores of these scales in D90G and in EOG were compared with those of 26 sex distribution-, severity of dementia-, and disease duration-matched inpatients with AD with late-onset (LOG). Compared with LOG, wakefulness was more impaired and waking up at night was more frequent in D90G, while memory, orientation and inappropriate behaviors were more severe in EOG. These results suggest that the clinical features of dementia in EOG were quantitatively different from those of LOG. In contrast, the clinical feature of dementia of D90G were sleep-wake pattern disturbance and were qualitatively different from those of LOG.

Age of Onset↗

Extracellular level of basolateral amygdalar dopamine responding to reversal of appetitive-conditioned discrimination in young and old rats.

Young and old rats, aged 3 and 24 months old, respectively, were conditioned to press a lever under lamp-on conditions for reward acquisition and lamp-off for no reward using a variable interval reinforcement schedule that averaged 15 s; i.e., the minimal requirement was 4 responses/min. Over a 30-day period, young and old groups showed increased response to lamp-on from 22 to 35/min and from 10 to 23/min, respectively, and shortened response to lamp-off after initial training. Response to lamp-on as a percentage of total response to lamp-on and -off (the discrimination ratio) was over 80%. For the next 30 days, reversal learning was imposed to reinforce discrimination of the lamp-off state. Young rats showed a steadily increasing discrimination ratio from 40% to 70%, and old rats from 30% to 60%. In comparison with the initial training, young rats showed a total response increase from 50% to 60%, while old rats showed an approximately 5% decrease without loss of reward-obtaining efficiency. In vivo microdialysis during reversal revealed that young rats had higher dopamine transmission in the basolateral amygdala than old rats. The dopamine level was positively correlated with the number of responses to state of reward in young rats and negatively with the numbers of both NRF and RF responses to lamp-on and -off states in old rats. These results suggest that in reversal discrimination, basolateral amygdalar dopamine efflux correlates with the manner of age-related conditioned response rather than the ability to learn.

Age Factors↗