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Y Uematsu

Publications and source records attributed to Y Uematsu.

At least 55 records · Page 3Linked to original sources
PubMed1995

[Intrasellar arachnoid cyst: a case report].

Intrasellar arachnoid cyst is very rare. We report a case of intrasellar arachnoid cyst. A 44-year-old male was admitted for evaluation of his headache and visual disturbance on August 6, 1993. Neurological examination revealed bilateral decreased visual acuity and visual field defect. Endocrinological examination showed panhypopituitarism. Other neurological findings were normal. X-ray film of the skull showed a ballooning dilation of the sella turcica with thinning of the sellar floor. CT scan showed a cystic lesion with CSF-density occupied the sella. After intravenous administration of contrast medium, the cyst showed no enhancement. MRI showed the intrasellar mass had the same characteristics as the surrounding subarachnoid space. Bilateral carotid angiographies demonstrated that the carotid siphons were stretched and displaced laterally, and the A1 portions of the anterior cerebral arteries were raised. We made a diagnosis of intrasellar cystic lesion. On August 18, the sella turcica was opened via the transsphenoidal rhinoseptal approach. The cyst contained CSF-like fluid, and a part of the cyst wall was resected. The cavity was filled with Gelfoam and the sellar floor was repaired with bone flap. Postoperatively, the patient's visual disturbance improved, but diabetis insipidus appeared and required hormonal replacement. The patient was discharged on September 27 with improvement of visual acuity and visual field. Histological examination demonstrated that the cyst wall consisted of thick arachnoidal cells with fibrous connective tissue. The arachnoidal cells with oval nuclei was stained with epithelial membrane antigen. Symptoms, signs and radiological findings of intrasellar arachnoid cyst are similar to those of various sellar lesions including pituitary adenoma, craniopharyngioma, empty sella, Rathke's cleft cyst, epidermoid et al.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

[Effects on cognitive function and activities of daily living after stereotactic thalamotomy for Parkinson's disease].

Stereotactic thalamotomy was performed in ten patients with Parkinson's disease for the suppression of their tremor. After VL-thalamotomy, contralateral tremor and rigidity disappeared or was significantly reduced. Activities of daily living (ADL) measured by functional independence measure and Parkinson's disability score were improved postoperatively in all patients. There was significant improvement in anxiety index. However, other neuropsychological tests showed no significant change postoperatively. ADL improved after thalamotomy. It is concluded that stereotactic VL-thalamotomy is a useful treatment which improves ADL without cognitive dysfunction.

Activities of Daily Living↗
PubMed1994

Pretreatment with interleukin-1 enhances survival of sympathetic ganglionic neuron grafts.

The effects of pretreatment with interleukin-1 (IL-1) on neurite growth and cell survival of rat superior cervical ganglion (SCG) explants were examined. Neonate rat SCG explants were cultured with serum-containing growth media. Pretreatment with IL-1 beta (30 U/ml) for 3 hours stimulated neurite outgrowth of the SCG explant, which was inhibited by the addition of anti-nerve growth factor (NGF) antibody to the growth medium. Adult rat autologous SCG with the same pretreatment and non-treated ganglia were transplanted into the lateral ventricle. Histological evaluation of the grafts 2 weeks after transplantation revealed that the pretreated SCG cells survived better. Pretreatment with IL-1 may achieve the NGF-mediated neurotrophic effect in sympathetic ganglionic neurons resulting in enhanced graft survival.

Animals↗
PubMed1994

[Histological analysis of craniopharyngiomas--with special reference to their histological origin and differentiation].

The histogenesis of craniopharyngiomas was immunohistochemically studied on the basis of cytokeratins (CK) expression, with special reference to histological subtype, i.e., the squamous type (Sq) and adamantinomatous type (Ad). Alcian-Blue staining and immunohistochemical expression of secretory component were also studied to assess secretory activity. Although combined expression of simple-, stratified-, and skin-type CK was detected in both Sq and Ad, the pattern of expression in Sq and Ad was different. Sq displayed epidermal differentiation of CK, and secretory activity was limited to the apical cells of Sq. Based on these findings, the histogenesis of Sq appeared to be from Rathke's pouch, but that of Ad remained obscure.

Adolescent↗
PubMed1994

Clinicopathological study of lymphomas in the central nervous system--with the reference to the recurrence and proliferative activity.

Nine cases of CNS lymphomas obtained by surgical resection or biopsy between 1984 and 1991 were examined. One case of intraorbital lymphoma was also studied. All patients underwent radiotherapy. In addition, 7 underwent steroid therapy and 4 underwent chemotherapy. The case comprised the following (LSG classification): small cell type (3), medium cell type (1), large cell type (3), and medium and large cell type (3). Immunohistochemically, LCA and B-26 immunopositivity were seen in all cases. Cytoplasmic Ig immunopositivity was observed in five cases. The mean AgNORs number was 4.63 (range: 1.8-7.2). The mean PCNA SI was 26.75 (range: 10.2-39.7). No correlation was found between LSG classification and proliferative activity. Although no correlation was found between AgNORs number and recurrence, the recurrent group showed tendency to have more AgNORs that the non-recurrent group. Although no correlation was found between PCNA SI and recurrence, the recurrent group showed tendency to have a higher PCNA SI than the non-recurrent group. The proliferative activity in AgNORs and PCNA studies may be considered as a prognostic indicator in CNS lymphomas.

Adult↗
PubMed1994

Cellular differentiation, secretory and proliferative activities of craniopharyngiomas.

The cellular differentiation of craniopharyngiomas was studied immunohistochemically by determining the expression of cytokeratins. Alcian-Blue staining was used to assess secretory activity and expression of AgNORs and PCNA as indicators of proliferative activity. Both, tumors of the adamantinomatous type and of the squamous type expressed complex type cytokeratins, with skin type differentiation being noted in some cases. In addition, epidermal differentiation of cytokeratins was found in the squamous types. Intracellular Alcian-Blue staining was limited to apical cells of tumors of the squamous type. Neither AgNORs staining nor PCNA staining proved statistically significant results with respect to the histological type of tumor or patient's age. However, PCNA staining was predominantly noted in basal cells of the squamous type tumors. Although their ultimate significance remains to be established, the results presented provide additional evidence with regard to the possible origin of both craniopharyngioma types, and suggest the potential value of some of the parameters studied as prognostic indicators.

Adolescent↗
PubMed1993

Cerebral blood flow in mitochondrial myopathy, encephalopathy, lactic acidosis, and strokelike episodes.

BACKGROUND AND PURPOSE: The precise mechanism of neurological symptoms with mitochondrial myopathy, encephalopathy, lactic acidosis, and strokelike episodes (MELAS) is still controversial. We investigated the correlation between strokelike episodes and cerebral blood flow in two patients with MELAS and discuss the pathogenesis of strokelike episodes with MELAS. SUMMARY OF REPORT: Cerebral dynamic computed tomography and cerebral angiography were used to measure cerebral circulation in the first case, that of a 20-year-old woman with MELAS. The second subject was a 13-year-old female who was studied with xenon-enhanced computed tomography. The cerebral blood flow studies were performed 3-72 hours after the onset of strokelike episodes. Serial cerebral angiography, dynamic computed tomography, and xenon-enhanced computed tomography showed vasodilation localized in the affected cerebral cortexes during strokelike episodes, without any reduction in regional cerebral blood flow. CONCLUSIONS: Our study suggests that the strokelike episodes associated with MELAS are different in origin from ischemic stroke.

Adolescent↗
PubMed1993

Cytokeratin immunohistochemical study of epithelial cysts in the central nervous system: with special reference to origins of colloid cyst of the third ventricle and Rathke's cleft cyst in the sella.

A variety of epithelial cysts in the central nervous system were examined immunohistochemically for expression of cytokeratins. Colloid cysts, Rathke's cleft cysts and epithelial cysts in the spinal canal expressed complex type cytokeratins, while enterogenous cysts and neuroectodermal cysts showed only simple type cytokeratins. Colloid cysts showed a pattern of cytokeratins similar to that of upper respiratory tract which is endodermal in origin. In contrast, Rathke's cleft cysts showed a pattern of cytokeratins similar to that of the adenohypophysis and salivary gland which are ectodermal in origin. The CK immunohistochemical studies are discussed with regards to diagnostic significance and origins of their cysts.

Adult↗
PubMed1993

[A case of chronic progressive external ophthalmoplegia with pituitary hypothyroidism].

We report a case of chronic progressive external ophthalmoplegia with pituitary hypothyroidism. This patient had complained of hearing-loss at the age of fourteen and loss of body weight at fifteen. She was examined by otorhinolaryngologists at large hospitals yearly over a period of 5-6 years, but hearing-loss remained unknown. As her ophthalmoplegia progressed (as is evident from family photographs from the age of sixteen onward), with hindsight it should have been recognized. When examined on October 11, 1991, she complained of ptosis, speech disturbance and dysphagia at the age of thirty-four. Neurological examination revealed limitation of ocular movement, bilateral ophthalmoplegia, facial muscle atrophy, and weak gag reflex. She showed muscle atrophy in her neck including both sternocleidomastoid, major and minor rhomboid, girdle and distal parts of upper and lower extremities. Muscle biopsy of her biceps demonstrated ragged-red fibers, cytochrome c oxidase (CCO) deficient fibers and deletion of mitochondrial DNA. A plain CT scan revealed bilateral periventricular lucency, and a brain MR image showed a normal sized pituitary gland but diffuse high-signal intensities in the both periventricular white matter with proton density weighted and T2-weighted axial MR image. And also her electroencephalogram showed diffuse 7 Hz slow waves in all areas and increased slow waves by hyperventilation, and all waves from I to V of the auditory brain stem response disappeared. The effect of TRH on serum TSH secretion was not evident in this patient. This case was ascertained to be chronic progressive external ophthalmoplegia with pituitary hypothyroid function.

Adult↗
PubMed1992

Exclusion and inclusion of alpha and beta T cell receptor alleles.

Exclusion and inclusion of T cell receptor (TCR) genes were analyzed in alpha beta TCR transgenic mice. Both transgenes are expressed unusually early on the surface of CD4-8-, HSA+, IL-2R- thymocytes. These progenitor cells give rise to progeny, which at the single-cell level contains endogenous alpha but not beta TCR-RNA as well as protein, in addition to products encoded by the transgenes. Thus, the surface expression of an alpha beta TCR does not prevent further alpha TCR rearrangement in immature thymocytes that still transcribe RAG-1 and RAG-2 genes. Reduced levels of RAG-1 and RAG-2 RNA are detectable only in CD4+8+ TCR high cells, which result from positive selection in the thymus. The results suggest that a developing T cell may try different alpha beta TCRs for binding to thymic MHC ligands, and that recombination at the alpha locus ceases only after positive selection.

Alleles↗
PubMed1992

Preferential association of alpha and beta chains of the T cell antigen receptor.

The cytotoxic T lymphocyte (CTL) clone B6.2.16 expresses a V beta 8.2/J beta 2.3/C beta 2-encoded T cell receptor (TcR) beta chain and an alpha chain that is encoded by a novel V alpha gene segment, J alpha 27 and C alpha. While expression of V alpha B6.2.16 and J alpha 27 is not detectable in lymph node cells of normal C57BL/6 mice, expression of these gene segments was readily seen in transgenic mice expressing the rearranged beta chain gene of the B6.2.16 T cell clone. This finding indicates that only a limited number of alpha chains can associate with the B6.2.16 beta chain and strongly suggests that the size of the TcR repertoire of mature T cells is not only limited by TcR ligand-mediated thymic selection but also by restrictions in alpha-beta combinatorial chain association.

Amino Acid Sequence↗
PubMed1992

The recurrence of primary intracranial germinomas. Special reference to germinoma with STGC (syncytiotrophoblastic giant cell).

Twenty three cases of primary intracranial germinomas including five cases of germinomas with syncytiotrophoblastic giant cells are studied and analyzed, with special reference to the recurrence under radiotherapy. The follow-up period for all cases was 7 months to 12 years (average: 5.8 years) with that for pure germinomas ranging from 8 months to 12 years (average: 5.7 years) and that for germinomas with syncytiotrophoblastic giant cells ranging from 7 months to 11 years (average: 6.3 years). Late recurrence was observed in three cases (3/23, 13%), developing outside of the initial irradiation field. With regard to recurrence, significant correlation to radiation fields was evident, while it was not to radiation doses. Furthermore, germinoma with syncytiotrophoblastic giant cells showed a more significant tendency to recur than pure germinoma. The radiotherapy of germinomas is discussed and the clinical features of germinoma with syncytiotrophoblastic giant cells are presented.

Adolescent↗
PubMed1992

A possible involvement of central atrial natriuretic peptide in cerebral cortical microcirculation.

The possible involvement of atrial natriuretic peptide (ANP) in cerebral cortical microcirculation was investigated in rats by means of laser-Doppler flowmetry and immunohistochemistry. In the laser-Doppler study, local cerebral blood flow (LCBF) changes after the administration of 10(-6) to 10(-8) mol/LANP solution or vehicle (saline solution) as an intracortical injection for 5 minutes were continuously monitored throughout the 30 minutes of the study and were expressed as percentages of preinjection values represented as 0%. The administration of 10(-6) to 10(-8) mol/LANP caused a significant decrease in LCBF; the onset of LCBF responses occurred within a few minutes after the start of the injection and the decrease in LCBF reached the maximum level within 7 to 10 minutes after the completion of the administration, after which LCBF gradually recovered. In the immunohistochemical study, no specific ANP immunoreactivity was found associated with the intraparenchymal blood vessels; however, ANP-immunoreactive neurons were observed primarily in the hypothalamus and septum, in which high concentrations of ANP-containing neurons have been identified. The data from the laser-Doppler study suggest that central ANP may produce a vasoconstriction of the intraparenchymal blood vessels, regardless of whether through direct action on these vessels or through the mediation by some system in the central nervous system. Because there is no evidence for ANP-containing nerves around these vessels, the role of central ANP in the cerebral circulation must await identification of the source of perivascular ANP.

Animals↗
PubMed1992

Meningeal melanocytoma: magnetic resonance imaging characteristics and pathological features. Case report.

A case of meningeal melanocytoma at the foramen magnum is reported in a 62-year-old man. Magnetic resonance (MR) imaging revealed characteristic signal patterns: homogeneous high intensity on the T1-weighted image and low intensity on the T2-weighted image. Light microscopy showed a histological appearance similar to that of melanotic meningioma. The ultrastructural features of the neoplastic cells were compatible with those of melanocytes, but they contained no features of arachnoidal cells. Immunohistochemical bromodeoxyuridine study revealed low proliferative activity among the neoplastic cells. The MR appearance and pathological features in this rare case of meningeal melanocytoma are demonstrated and discussed.

Humans↗
PubMed1992

Bilateral morning glory syndrome associated with sphenoid encephalocele. Case report.

Morning glory syndrome is a congenital anomaly of the optic disc in which the disc is enlarged and excavated, with white glial tissue in the center. A case is presented of morning glory syndrome associated with sphenoid encephalocele, median cleft lip, and agenesis of the corpus callosum. A 22-day-old boy was referred to the Wakayama Medical College Hospital for management of dyspnea due to a soft-tissue mass in the oral cavity. Magnetic resonance imaging revealed a mass extending through a bone defect in the sphenoid region and into the oral cavity. Surgical repair was attempted through a bifrontal craniotomy. A bone defect was identified in the sphenoid plate, through which the arachnoid membrane was connected to the oral cavity. Both optic nerves were elongated and adhered to the encephalocele. The wall of the meningocele was compressed digitally through the oral cavity and sutured to the dura mater of the bone defect. The operative findings suggest that a basal encephalocele protruding from a bone defect in the sphenoid plate may disturb the normal development of the optic nerve.

Abnormalities, Multiple↗
PubMed1991

The T-cell-receptor repertoire in the synovial fluid of a patient with rheumatoid arthritis is polyclonal.

We have analyzed the T-cell-receptor repertoire expressed in the synovial fluid of a patient with rheumatoid arthritis by using an inverse polymerase chain reaction. Total RNA was isolated from Ficoll-purified mononuclear cells and converted into circularized double-stranded cDNA. Specific amplification of alpha- and beta-chain variable regions (V alpha and V beta) was achieved with inverted alpha- and beta-chain constant region (C alpha and C beta) primer pairs, and the amplification products were cloned into phage vectors. A total of 78 alpha and 76 beta clones were sequenced, and 67 and 72 productively rearranged alpha and beta genes were identified, respectively. Thirty-one V alpha, 33 alpha-chain joining region (J alpha), 29 V beta, and 12 beta-chain joining region (J beta) gene segments were found in the productively rearranged clones, indicating that the T-cell repertoire expressed in the synovial fluid of this RA patient is highly heterogenous and polyclonal. Comparison of peripheral blood and synovial fluid repertoires showed that the most abundant V beta sequences, V beta 2.1 and V beta 3.1, were enriched in the inflamed joint by a factor of 2 to 3. It is possible that T cells expressing these V beta gene segments, which recognize bacterial superantigens, play a role in the disease.

Amino Acid Sequence↗
PubMed1991

A novel and rapid cloning method for the T-cell receptor variable region sequences.

Conventional polymerase chain reactions (PCR) require sequence information on both ends of the DNA to be amplified. The novel technique described here allows the amplification of cDNA fragments with sequence information from one end only. Blunt-ended double-strand cDNA is prepared, circularized with T4 DNA ligase and used as a PCR template. The two PCR primers are designed to hybridize to the known region in an outward orientation allowing the amplification of the unknown sequence. The method was established using the alpha-chain of T-cell antigen receptors (Tcr) as an example. The cDNA synthesized from 1 microgram of total RNA from human peripheral lymphocytes was amplified and cloned resulting in a library of 1-2 x 10(6) Tcr-specific clones. The method should also be useful for cloning full-length cDNA or for the identification of new members of a gene family that share a conserved domain.

Base Sequence↗