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Biomedical subjects

Y Sano

Publications and source records attributed to Y Sano.

At least 523 records · Page 29Linked to original sources
PubMedDate not supplied

Postnatal ontogeny of catecholamine and somatostatin neuron systems in the median eminence of the rat as revealed by a colocalization technique.

The ontogenetic development of catecholamine (CA) and somatostatin containing nerve terminals in the rostral, central and caudal median eminence (ME) of the rat was investigated by combining fluorescence histochemistry and immunohistochemistry in the same tissue section. Somatostatin terminals were detected earlier in development than CA terminals and had already appeared in the lateral part of the external layer of the central ME by the 1st postnatal day. CA nerve terminals were first observed in the same region of the ME on the 7th postnatal day. At about this stage both types of terminals seemed to show early signs of a correlation in their distribution which became progressively closer as maturation proceeded. Their distribution reached a stable condition in density and pattern on the 21st postnatal day when the majority were found in the lateral part of the external layer of the central ME, in the basal part of the brain just dorsal to the tuberoinfundibular sulcus and in the upper and lower labia of the tuberoinfundibular stalk. They subsequently matured to the adult pattern of stabilized distribution and anatomical relationship. It was also established that on the 28th postnatal day the somatostatin immunoreactive terminals reached a greater concentration than at any other stage of development including that of the adult.

Aging↗
PubMedDate not supplied

The problem of de novo colorectal carcinoma.

From April 1985 to March 1995, colonoscopy was carried out at our institution in 24,059 patients, 31,800 times in symptomatic and/or asymptomatic average risk persons. 184 submucosal invasive carcinomas were detected. Unlike protruding-type lesion, the depressed-type invades the submucosal layer, even though the size is within 10 mm. The depressed type of invasive carcinoma accounted for 20 lesions, and represented 10.9% (20 of 184) of all the invasive carcinomas. The pit pattern of depressed-type lesions shows a small round pit (type IIIs pit pattern) and that of carcinoma lesions shows the irregular pit and non-structure (type V pit pattern).

Adenoma↗
PubMedDate not supplied

Hyperintense signal of the posterior pituitary on T1-weighted MR images: an experimental study.

The origin of the hyperintense signal (HIS) of the pituitary gland posterior lobe (PL) on T1-weighted magnetic resonance (MR) images was investigated. Six rabbits were imaged on a 1.5 T device before and after 2 weeks' feeding of hypertonic saline solution (phase I). Two were killed soon after the second imaging; the pituitary gland was examined histochemically for neurosecretory granules containing antidiuretic hormone (ADH). The other four rabbits were given regular water for another 2 weeks (phase II) and then were again imaged. The plasma ADH level was monitored at each imaging session. In all subjects, the signal intensity of the PL decreased at the end of phase I, and the HIS reappeared at the end of phase II. The neurosecretory granules in the PL significantly diminished in number in phase I. Plasma ADH levels significantly increased in phase I and returned to their normal range in phase II. These clear correlations between MR findings and hormonal and histochemical results strongly suggest that the source of the HIS of the PL is the neurosecretory granules containing ADH.

Animals↗
PubMedDate not supplied

Can Mycobacterium tuberculosis infection prevent asthma and other allergic disorders?

It is generally considered that tuberculosis (TB) is a disease which upregulates Th1 cell function. There is a hypothesis that infection of Mycobacterium tuberculosis may prevent allergic disorders such as bronchial asthma. However, our clinical experience of patients with TB somewhat conflicts this hypothesis. Hence, we investigated Th1/Th2 balance in the peripheral blood of patients with active TB by measuring serum levels of IgE antibody and by intracellular cytokine assay. We found that serum levels of IgE in the patients with active TB were significantly higher than in those with lung cancer or with COPD. In the TB patients, titers of IgE tended to correlate with disease severity. Intracellular cytokine assay demonstrated that IFN-gamma-positive cells were significantly decreased in the patients with active TB compared to normal controls. The ratio of IFN-gamma-positive (Th1-like)/IL-4-positive (Th2-like) cells was remarkably reduced in the TB patients (p < 0.0001). This ratio showed a significant negative correlation with erythrocyte sedimentation rate and with C-reactive protein. Therapy against TB for 2-3 months did not result in significant changes of the Th1/Th2 ratio. These findings suggest that infection of M. tuberculosis does not systematically upregulate Th1 cells in some patients, and is unlikely to prevent allergic disorders like asthma.

Asthma↗