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Biomedical subjects

T Yoshihara

Publications and source records attributed to T Yoshihara.

At least 37 records · Page 2Linked to original sources
PubMed2001

A novel missense mutation in the early growth response 2 gene associated with late-onset Charcot--Marie--Tooth disease type 1.

A novel mutation (Arg381Cys) in the second zinc-finger domain of early growth response 2 (EGR2) was identified in a late-onset Charcot--Marie--Tooth disease type 1 (CMT1) patient. This patient had initial symptoms of numbness and weakness in the leg at age 59, and a median nerve motor conduction velocity of 27 m/s. A sural nerve biopsy showed a severe loss of myelinated fibers with numerous onion bulbs. This is the first report of the EGR2 mutation presenting a late onset of CMT1 phenotype. Its mutation was a different amino acid substitution at codon 381 (Arg381His) which demonstrated congenital hypomyelinating neuropathy or early-onset CMT1. This report suggests that the EGR2 mutation represents divergent phenotypes at codon 381, which may be a mutation hotspot.

Aged↗
PubMed2001

Surfactant proteins in bronchoalveolar lavage fluid of horses: assay technique and changes following road transport.

An enzyme-linked immunosorbent assay (ELISA) was developed for equine surfactant proteins SP-A and SP-D in bronchoalveolar lavage fluid (BALF). Anti-equine SP-A or SP-D monoclonal antibodies (mAb) were produced by hybridoma technology, purified by the antibody purification reagent, and analysed by Western blotting analysis. The immunoreaction (two-site sandwich ELISA) with a mAb, peroxidase-labelled mAb and BALF sample was carried out simultaneously and analytical recovery and precision were assayed. Six mAb for SP-A and four mAb for SP-D were successfully cloned in limiting dilution to monoclonality. These mAb were reacted with equine SP-A or SP-D on Western blotting analysis. For SP-A, a combination of solid-phase TA08 and horseradish peroxidase (HRP)-conjugated WA28 was found to be more sensitive than other combinations, gave a good dose response and was capable of measuring 0.78 to 100 ng of protein/ml. For SP-D, a combination of solid-phase TD13 and HRP-conjugated WD19 was found to be more sensitive than other combinations, had a good dose response and was capable of measuring 0.78 to 200 ng of protein/ml. The assay was used to determine the effect of 41 hours of road transport on the concentrations of SP-A and SP-D in the BALF of 30 horses. The concentrations of SP-A and SP-D decreased by 55 per cent and 36 per cent, respectively, decreases similar to the decrease in phosphatidylglycerol concentration previously reported by the authors.

Animals↗
PubMed2001

Expression of vascular endothelial growth factors (VEGF-A/VEGF-1 and VEGF-C/VEGF-2) in postmenopausal uterine endometrial carcinoma.

OBJECTIVE: We investigated the expression of two angiogenic vascular endothelial growth factors, VEGF-A/VEGF-1 and VEGF-C/VEGF-2, in 228 cases of uterine endometrial carcinomas from postmenopausal patients to evaluate the correlation with histopathologic features and clinical outcome. METHODS: Immunohistochemistry was used to assess VEGF-A/VEGF-1 and VEGF-C/VEGF-2 expression in 228 primary surgically treated cases of postmenopausal endometrial carcinomas and the results were statistically analyzed in relation to vascular invasion, depth of invasion (myometrial vs serosal-parametrial invasion), lymphatic vessel invasion, lymph node metastasis, disease-free 5-year survival rate (DF5YR), and disease-free 10 year-survival rate (DF10YR). RESULTS: The results of univariate analysis showed that VEGF-A/VEGF-1 and VEGF-C/VEGF-2 expression correlated with vascular invasion (P < 0.0001, P = 0.0006), depth of invasion (P = 0.0004, P = 0.043), lymphatic vessel invasion (P = 0.021, P < 0.0001), lymph node metastasis (P = 0.0017, P = 0.0008), DF5YR (P = 0.0081, P = 0.0002), and DF10YR (P = 0.0077, P = 0.0001). Multivariate analysis showed that lymph node metastasis (P = 0.0017, P = 0.0008), parametrial-serosal invasion (P < 0.0001, P < 0.0001), and VEGF-C/VEGF-2-positive status (P = 0.03, P = 0.01) were significant factors in DF5YR and DF10YR. CONCLUSIONS: We conclude that VEGF-A/VEGF-1 and VEGF-C/VEGF-2 expression was predictive of these histopathologic features of endometrial carcinoma and clinical outcome.

Adult↗
PubMed2001

Risk factors for cytomegalovirus retinitis following bone marrow transplantation from unrelated donors in patients with severe aplastic anemia or myelodysplasia.

Two cases of cytomegalovirus (CMV) retinitis following bone marrow transplantation (BMT) from unrelated donors are reported. 1 patient had been treated for severe aplastic anemia (SAA) and the other for hypoplastic myelodysplastic syndrome (MDS). Because first line therapy with antithymocyte globulin (ATG) and cyclosporin A (CsA) had failed, BMT was performed following a conditioning regimen of ATG, cyclophosphamide, and total lymphoid irradiation. Treatment for CMV retinitis was successfully carried out with gancyclovir (systemic and intraocular injection), foscarnet, and photocoagulation (Case 1) and gancyclovir and foscarnet (Case 2). Both patients also developed Epstein-Barr virus-associated lymphoproliferative disease (EBV-LPD). We compared these 2 cases with 14 SAA patients who did not develop CMV retinitis after BMT using marrow from either HLA-identical siblings (n = 9) or from unrelated donors (n = 5). Unlike the retinitis patients, the latter 5 patients received ATG only once. The retinitis patients had significantly lower CD4+ T-cell levels in their peripheral blood than the 14 patients who did not develop CMV retinitis. We believe that repeated treatment with ATG and transplantation from unrelated donors may lead to immune dysfunction that could increase the likelihood of CMV retinitis, as well as LPD. For such BMT patients, regular ophthalmic examinations and careful testing for CMV antigenemia are recommended.

Adolescent↗
PubMed2001

Expression of rolB in apomictic Hieracium piloselloides Vill. causes ectopic meristems in planta and changes in ovule formation, where apomixis initiates at higher frequency.

The effects of the Agrobacterium rhizogenes rolB oncogene on apomixis were examined in the facultative apomictic plant Hieracium piloselloides because the oncogene has been shown to alter plant growth, morphogenesis and cellular sensitivity to auxin. Introduction of rolB under the control of either its own promoter or the CaMV35S promoter induced ectopic meristem formation from the inflorescence, confirming in planta a meristem-inducing role for this oncogene previously observed only in tissue culture. These ectopic meristems formed vegetative rosettes and floral plant organs. Upon immersion in water these meristems generated roots, suggesting that meristem commitment towards the generation of a specific organ type is a separate and later event that is dependent upon the developmental context. Ovule identity and form was altered in ectopically induced florets in plants expressing the CaMV35S::rolB construct. In contrast to the ovules of untransformed apomictic plants, the sexual process ceased earlier, prior to meiosis, yet surprisingly, apomixis initiated from a greater number of cells, and embryos and endosperm continued to develop in the structurally altered ovules. The alternative possibilities that the effects on reproduction might result from rolB influencing cellular response to auxin, or from alterations in cell signaling caused by changes in ovule morphology that are induced because of the expression of the oncogene are discussed.

Asteraceae↗
PubMed2001

Morphology of the nerve endings in laryngeal mucosa of the horse.

To discuss the significance of laryngeal sensation on various disorders of the horse, we studied the morphological and topographical characteristics of sensory structures in the laryngeal mucosa using immunohistochemistry and immunoelectron microscopy. Various sensory structures, i.e. glomerular endings, taste buds and intraepithelial free nerve endings, were found in the laryngeal mucosa by immunohistochemistry for protein gene product 9.5 (PGP 9.5) and neurofilament 200kD (NF200). Glomerular nerve endings were distributed mainly in the epiglottic mucosa; some endings were also found in the arytenoid region arising from thick nerve fibres running through the subepithelial connective tissue. Some terminals directly contacted the epithelial cells. Taste buds were distributed in the epithelium of the epiglottis and aryepiglottic fold. In the whole mount preparation, the taste buds were supplied by the terminal branching of the thick nerve fibres. In some cases, the taste buds were arranged around the opening of the duct of the epiglottic glands. The intraepithelial free nerve endings were found to be immunoreactive for substance P (SP) and calcitonin gene-related peptide (CGRP). These nerve endings were surrounded by the polygonal stratified epithelial cells in the supraglottic region, and by the ciliated cells in the subglottic region. The density of the intraepithelial free nerve endings was highest in the corniculate process of the arytenoid region and lowest in the vocal cord mucosa. The densities of CGRP- and SP-immunoreactive nerve endings in the arytenoid region were (mean +/- s.d.) 30.6+/-12.0 and 10.0+/-4.9 per unit epithelial length (1 mm), respectively and in the vocal fold mucosa, 1.1+/-0.9 and 0.8+/-0.7, respectively. Approximately one half of the CGRP immunoreactive nerve endings were immunoreactive for SP, and most SP-immunoreactive nerve endings were also immunoreactive for CGRP. Well-developed subepithelial plexus with numerous intraepithelial fibres were observed in flat or round mucosal projections that existed on the corniculate process of the arytenoid region. In conclusion, the laryngeal mucosa of the horse seems to have morphology- and/or location-dependent sensory mechanisms against various endo-and exogenious stimuli.

Animals↗
PubMed2001

Occlusal disharmony affects plasma corticosterone and hypothalamic noradrenaline release in rats.

Few neuro-endocrinological studies have examined the relationship between occlusal disharmony and stress. To determine the effect of occlusal disharmony on the central nervous system, we measured plasma corticosterone and extracellular noradrenaline in the vicinity of the hypothalamic paraventricular nucleus in rats both with and without incisal caps. After the caps were set, plasma corticosterone and extracellular noradrenaline levels gradually increased, reaching a peak at 8.5 and 6.5 hours, respectively, after which they decreased. Furthermore, plasma corticosterone and extracellular noradrenaline levels increased in a circadian fashion around the onset of the dark phase in rats without caps, but not in rats with caps. These results suggest that occlusal disharmony causes chronic stress in the rat.

Analysis of Variance↗
PubMed2001

Localization of cytosolic NADP-dependent isocitrate dehydrogenase in the peroxisomes of rat liver cells: biochemical and immunocytochemical studies.

Two types of NADP-dependent isocitrate dehydrogenases (ICDs) have been reported: mitochondrial (ICD1) and cytosolic (ICD2). The C-terminal amino acid sequence of ICD2 has a tripeptide peroxisome targeting signal 1 sequence (PTS1). After differential centrifugation of the postnuclear fraction of rat liver homogenate, approximately 75% of ICD activity was found in the cytosolic fraction. To elucidate the true localization of ICD2 in rat hepatocytes, we analyzed the distribution of ICD activity and immunoreactivity in fractions isolated by Nycodenz gradient centrifugation and immunocytochemical localization of ICD2 antigenic sites in the cells. On Nycodenz gradient centrifugation of the light mitochondrial fraction, ICD2 activity was distributed in the fractions in which activity of catalase, a peroxisomal marker, was also detected, but a low level of activity was also detected in the fractions containing activity for succinate cytochrome C reductase (a mitochondrial marker) and acid phosphatase (a lysosomal marker). We have purified ICD2 from rat liver homogenate and raised a specific antibody to the enzyme. On SDS-PAGE, a single band with a molecular mass of 47 kD was observed, and on immunoblotting analysis of rat liver homogenate a single signal was detected. Double staining of catalase and ICD2 in rat liver revealed co-localization of both enzymes in the same cytoplasmic granules. Immunoelectron microscopy revealed gold particles with antigenic sites of ICD2 present mainly in peroxisomes. The results clearly indicated that ICD2 is a peroxisomal enzyme in rat hepatocytes. ICD2 has been regarded as a cytosolic enzyme, probably because the enzyme easily leaks out of peroxisomes during homogenization. (J Histochem Cytochem 49:1123-1131, 2001)

Animals↗
PubMed2001

Structural confirmation of 15-norlubiminol and 15-norepilubiminol, isolated from Solanum aethiopicum, by chemical conversion from lubimin and epilubimin, and their antifungal activity.

15-Norlubiminol and 15-norepilubiminol were obtained from Solanum aethiopicum as an inseparable 1:1 mixture in a relatively poor yield to that of the major phytoalexins, lubimin and epilubimin. Their structures were confirmed by chemical conversion starting from lubimin and epilubimin. Baeyer-Villiger oxidation of the protected lubimins with m-chloroperoxybenzoic acid provided the desired formates. Deoxygenation with triphenylphosphine selenide and subsequent methanolysis provided 15-norlubiminols, whose 1H-NMR spectra were respectively identical with that of the corresponding isomer in the natural 15-norlubiminol mixture. The antifungal activity of 15-norlubiminols would be weaker than that of lubimins.

Antifungal Agents↗
PubMed2001

Histoplasmosis in the lung of a race horse with yersiniosis.

A 4-year-old female thoroughbred race horse died of acute peritonitis caused by necrotizing granulomatous duodenitis. Yersinia enterocolitica was immunohistochemically demonstrated in macrophages in granulomas developed in the duodenum, lung, liver and abdominal lymph nodes. The yeast-like fungi were found in the cytoplasmic vacuoles of macrophages in the lung that infiltrated into the granulomas and surrounding alveoli with congestive edema. The yeast-like fungi were positively stained by Gomori-Grocott chromic acid methenamine silver stain and immuno-histochemically stained with anti-histoplasma antibody. In this case, it was considered that granulomas formed in the duodenum, lung, liver and abdominal lymph nodes were primarily caused by Yersinia enterocolitica due to idiopathic weakening of the immune system. Yeast-like fungi immunohistochemically identified as histoplasmas secondarily infected the lung. This is the first case regarded as equine histoplasmosis capsulati in Japan.

Animals↗
PubMed2001

[AML(M7) associated with t(16;21)(p11;q22) showing relapse after unrelated bone marrow transplantation and disappearance of TLS/FUS-ERG mRNA].

A 3-year-old boy with poorly prognostic acute megakaryoblastic leukemia (AML M7) showing t(16;21)(p11;q22) karyotype underwent unrelated bone marrow transplantation (U-BMT) during his first hematological remission. The conditioning regimen consisted of BU, VP-16 and L-PAM. Engraftment was smooth, but the patient developed grade I acute GVHD. During hematological remission before U-BMT, the TLS/FUS-ERG chimeric transcript of t(16;21)(p11;q22) was consistently detectable as minimal residual disease (MRD) by RT-PCR. However, after U-BMT it soon became undetectable. There was no detectable MRD until 7 months after U-BMT, but bone marrow relapse occurred 10 months after U-BMT. We consider that U-BMT is a promising treatment for t(16;21)(p11;q22) AML. However, an intensified conditioning regimen or modification of GVHD prophylaxis is needed.

Bone Marrow Transplantation↗
PubMed2000

Two novel genes, human neugrin and mouse m-neugrin, are upregulated with neuronal differentiation in neuroblastoma cells.

We herein report two new genes, human neugrin and mouse homologue m-neugrin, found by screening the cDNA library for the human spinal cord. The neugrin mRNA encodes 219 amino acids and its deduced amino acid sequence contains an NLS-like domain. No previously known motif is found in it. m-neugrin mRNA encodes 233 amino acids. Neugrin and m-Neugrin are 70% homologous in amino acid sequence. Northern analysis revealed that neugrin was strongly expressed in the heart, brain, and skeletal muscle, and m-neugrin in the liver, kidney, and brain. A transfection study indicated that these proteins are localized in the nucleus. Although the expression of neugrin was found to be ubiquitous in the nervous system, in situ hybridization showed that both neugrin and m-neugrin were expressed mainly in the neurons rather than the glial cells. Their expression was highly upregulated with the neurite outgrowth associated with neuronal differentiation in neuroblastoma cell lines. These results indicate that neugrin and m-neugrin are mainly expressed in neurons in the nervous system, and play an important role in the process of neuronal differentiation.

Amino Acid Sequence↗
PubMed2000

Mutations in the peripheral myelin protein zero and connexin32 genes detected by non-isotopic RNase cleavage assay and their phenotypes in Japanese patients with Charcot-Marie-Tooth disease.

Mutations of myelin protein zero (MPZ) and connexin32 (Cx32) genes were examined in 70 unrelated Japanese patients with Charcot-Marie-Tooth disease (CMT) without PMP22 gene duplication. A new method, which could detect base pair mismatches with Rnase cleavage on agarose gel electrophoresis, identified 5 and 4 mutations of the MPZ and Cx32 genes, respectively, including one novel mutation (Ser128Ter) of Cx32. This non-isotopic RNase cleavage assay (NIRCA) employed in the present study is very suitable for exploring mutations of MPZ and Cx32 genes in a large number of CMT patients, as the phenotype of patients with CMT is greatly divergent from demyelinating to axonal pathology.

Adolescent↗