Biomedical subjects

Satoshi Horiguchi

Publications and source records attributed to Satoshi Horiguchi.

5 recordsLinked to original sources

PubMed2006

Pituicytoma. Two case reports.

Pituicytoma is a rare tumor in the sellar or suprasellar region with distinct histological characteristics of glial neoplasm. A 42-year-old woman presented with a history of amenorrhea and vertigo, and a 62-year-old woman presented with mild headache. Both patients had mild hyperprolactinemia and one had mild anterior pituitary dysfunction. They underwent transcranial partial resection of a suprasellar tumor. The tumors were characterized by storiform pattern of elongated cells immunoreactive for S-100 protein and glial fibrillary acidic protein. Ultrastructural study showed abundant cytoplasmic intermediate filaments and tumor/blood vessel basal lamina, but no desmosomes between tumor cells. The residual tumors showed no changes in size without adjuvant therapy at 56 and 18 months after surgery. Pituicytoma is a glial neoplasm of adults with low proliferative activity. Patients often present with visual symptoms or anterior pituitary dysfunction. Symptoms and signs of neurohypophysis are rare. Neuroimaging reveals an intra- or suprasellar mass with non-specific features. The prognosis and role of adjuvant therapy remain unclear for this discrete noninfiltrative glioma.

Adult↗

PubMed2005

Estrogen promotes differentiation and survival of dopaminergic neurons derived from human neural stem cells.

To investigate the effect of estrogen on neuronal differentiation, especially on dopaminergic (DA) neurons, human neural stem cells (NSCs) were differentiated in the presence of 17beta-estradiol. NSCs gave rise to tyrosine hydroxylase (TH)-positive neurons in vitro, the proportion of which was increased by 17beta-estradiol. Increase in TH-positive neurons was abrogated by an estrogen receptor (ER) antagonist, ICI182780, suggesting ERs play a role in differentiation of DA neurons. The observation that ERs were expressed in both proliferating NSCs and postmitotic DA neurons suggested that increase in TH-positive neurons was due to induction and support of DA neurons. 17beta-Estradiol also increased the number of DA neurons derived from human NSCs in vivo when the cells were grafted into mouse brains. These results support a possible role for estrogen in the transplantation of NSCs for Parkinson's disease.

Animals↗

PubMed2005

Endoscopic vocal cord medialization: a new surgical technique without neck incision for laryngeal palsy.

Different types of surgery have been reported for glottal insufficiency due to unilateral vocal cord paralysis. We recently developed a new surgical technique of fascia implantation known as vocal cord medialization. This new method achieves a wide glottal gap during phonation, without the use of an external approach. This new technique is described in detail herein, together with the satisfactory results we obtained in six cases of unilateral vocal cord paralysis with a wide glottal gap during phonation. We recommend this technique in cases of unilateral vocal cord paralysis in which both a satisfactory clinical result and an aesthetically pleasing cosmetic result are required.

Fascia↗

PubMed2004

Neural precursor cells derived from human embryonic brain retain regional specificity.

Recent studies have revealed that neural precursor cells can be expanded not only from the subventricular zone and hippocampus but also from other regions of the human embryonic brain. To determine the regional differences of these precursor cells, we divided the brain of a 9-week-old human embryo into four parts, i.e., telencephalon, diencephalon, mesencephalon, and rhombencephalon. All cultures of the tissues yielded neurospheres, and these spheres gave rise to neurons, astrocytes, and oligodendrocytes. An analysis of clonal populations revealed that these precursor cells were multipotent, and two region-specific differences in neural precursor cells were revealed: 1) The precursor cells from the rostral part of the brain tended to proliferate faster than those from the caudal part, and 2) the precursor cells from the diencephalon and mesencephalon gave rise to more tyrosine hydoxylase (TH)-positive neurons than those from the telencephalon and rhombencephalon. When 50-day-cultured spheres were caused to differentiate, the percentage of TH-positive cells per total cell population was 1.2% for diencephalic and mesencephalic precursors, whereas it was 0.4% for telencephalic and rhombencephalic ones. Furthermore, the TH-positive cells from diencephalic and mesencephalic precursors were large, multipolar, and gamma-aminobutyric acid (GABA)-negative, which suggested that these cells were midbrain dopaminergic neurons. In contrast, TH-positive cells from telencephalic and rhombencephalic precursors were small, bipolar, and GABA-positive. These results suggest that human neural precursor cells might have the potential to differentiate into a variety of cells but retain regional specificity.

Animals↗

PubMed2003

[A case presenting vertical one-and-a-half syndrome and seesaw nystagmus due to thalamomesencephalic infarction].

A 58-year-old woman presented, conjugate upgaze palsy and monocular paresis of downward gaze in the ipsilateral eye (vertical one-and-a-half syndrome; VOHS) as well as seesaw nystagmus (SSN). Vertical oculocephalic response and conjugate horizontal gaze were preserved. Magnetic resonance imaging revealed a right thalamo-mesencephalic infarction including the rostral interstitial nucleus of the medial longitudinal fasciculus (riMLF) and the interstitial nucleus of Cajal. On the 22nd hospital day SSN was disappeared, and then on the 32nd day VOHS was improved. The lesions of VOHS may have affected the efferent tracts of riMLF and the descending fibres to the ipsilateral subnucleus of the inferior rectus and contralateral subnucleus of the superior oblique. Furthermore, it was assumed that SSN was caused simultaneously by a lesion in the interstitial nucleus of Cajal existing in the adjacent area of riMLF.

Cerebral Infarction↗