Biomedical subjects

K Tashiro

Publications and source records attributed to K Tashiro.

At least 199 records · Page 11Linked to original sources

PubMed1998

[Bladder cancer in patients over 80 years old].

We studied 86 patients with bladder cancer who were 80 years old and over. All were studied at the time of their first presentation for treatment in our hospital. About 40% of then were somewhat limited in performing usual daily activities before the first treatment, and they could not come to the hospital by themselves. Tumors in patients were larger, of higher grade and more invasive than those in younger patients. Transurethral resection of the bladder tumor (TUR-Bt) was done in 94% of patients with a superficial tumor and in 56% of those an invasive tumor. The recurrence rates after TUR-Bt for superficial tumor were 48%, 64% and 89% in 1 year, 3 years and 5 years, respectively. Recurrence rates were significantly different in younger patients. Overall cancer related survival rates were 86%, 60%, and 56% in 1 year, 3 years and 5 years, respectively. The outcome were significantly worse in patients over 80 years old than in those under 79 years old. To improve the outcome of treatment for bladder cancer in patients over 80 years old, cooperation among doctors, patients and families was important.

Aged↗

PubMed1998

[Magnetic resonance images of hematospermia].

BACKGROUND: We performed MRI (magnetic resonance imaging) in the pelvic region of 70 cases with hematospermia and conducted a study on the abnormal MRI findings to which hematospermia could be attributed. METHODS: We conducted a study on the morphological anomaly and change in the signal intensity in the prostate gland and of the seminal vesicle as well as on the presence or absence of dilation in the plexus venous surrounding the deferent duct or the prostate gland out of the abnormal MRI findings. As for the seminal vesicle, the patients whose seminal vesicle was seen in higher intensity than the prostate gland in T1 weighted images were diagnosed as having hemorrhagic focus and the patients whose seminal vesicle was seen in low intensity both in T1 and T2 weighted images were diagnosed as having fibrosis caused by chronic inflammation. RESULTS: Abnormal MRI findings were seen in 40 out of the 70 cases (57%). Anomaly in the prostate gland was indicated in 6 (9%) cases. Abnormality in the seminal vesicle was indicated in 30 cases (43%) including hemorrhage of seminal vesicle in 25 cases, chronic inflammation in five cases and cyst of seminal vesicle in one case. CONCLUSION: In conducting an examination of the patients with hematospermia, MRI is the noninvasive and reproducible method and it is possible to identify the hemorrhagic region. Therefore, MRI is thought to be useful to identify the causal organs of hematospermia.

Adult↗

PubMed1998

[An autopsy case of rigid spine syndrome].

We reported an autopsy case of rigid spine syndrome. A 20-year-old woman developed severe respiratory failure despite well-preserved muscle strength in her extremities. Although she had mechanical ventilation during sleep, she had normal arterial blood gas values during daytime. She was found dead in a morning approximately 71/2 years after the onset of the respiratory symptoms. At autopsy, the respiratory diaphragm and intercostal muscles, and the truncal paravertebral and sternocleidomastoid muscles were more significantly affected than the limb muscles. Many corpora amylacea were found in the whole spinal cord, though the significance remains to be elucidated.

Adult↗

PubMed1998

Features of spontaneous improvement in syringomyelia with low-situated cerebellar tonsils.

We analysed six patients who showed spontaneous improvement among the 19 nonsurgically treated cases of syringomyelia with low-situated cerebellar tonsils who visited our outpatient clinic. MR images both before and after improvement were available for two of these patients; CT-myelography before improvement and MR images after improvement were used for two patients; and in the remaining two patients, MR images after improvement only were used. Consequently, we were able to abstract several features from detailed and precise neurological and radiological evaluations of these patients. These features consisted of mild (rather than severe) disability, as well as four radiological features--a rounded shape of the lower edge of the cerebellar tonsils, a low tightness of the foramen magnum, an elevation of the tonsils during the course of the disease. Results of our radiological analyses were consistent with the theories proposed for the pathogenesis of syringomyelia in the light of the CSF flow around the foramen magnum. We propose that the features we have isolated are useful in determining treatment policies and prognoses of patients with syringomyelia accompanied by low-situated cerebellar tonsils.

Adult↗

PubMed1998

[Initial symptoms and mode of neurological progression in spinocerebellar ataxia type 6 (SCA6)].

Spinocerebellar ataxia type 6 (SCA6) is genetically defined as a group of SCA characterized by late-onset pure cerebellar ataxia clinically and by a small CAG repeat expansion in the gene encoding the alpha 1A-voltage-dependent-Ca channel subunit (CACNL1A4) on chromosome 19p13.1 genetically. We analyzed the initial symptoms and the mode of progression in this disorder on 25 genetically verified patients. The initial symptoms were recurrent episodes of transient vertigo (72%) or unsteady gait (28%). Neurologically, they showed apparent gaze-evoked nystagmus (92%), transient positional nystagmus (83%), and periodic alternating nystagmus (4%), in addition to cerebellar ataxia. In addition to these episodic symptoms, all patients developed progressive cerebellar ataxia over years. These fluctuating symptoms at the initial stage of the illness were clearly different from those of other SCA, rather overlapping with those of episodic ataxia type 2 (EA2), an allelic disorder of SCA6. The clinical similarity indicates that there might be a common mechanism at least in part causing these two disorders. The mode of progression and their neurological features were also presented.

Adult↗

PubMed1998

[Periodic alternating nystagmus in spinocerebellar ataxia type 6 (SCA 6)].

We report a 61-year-old man with SCA 6 manifesting periodic alternating nystagmus (PAN). He first noted transient, recurrent episodes of "dizziness" at age 56. The symptom appeared several times a day, lasting for 3 years. At age 59, unsteady gait developed insidiously. On neurological examination, he showed limb and truncal ataxia, marked gaze nystagmus, and positional nystagmus. Thereafter, his ataxia became worse and PAN developed. Brain MRI showed pathologic atrophy which was confined to the cerebellum. PAN was rarely reported in spinocerebellar ataxia, being not described in SCA 6. The episodic "dizziness" at the initial stage has not gained much attention. Our observation indicates that the initial manifestation of SCA 6 overlaps with that of episodic ataxia type 2, an allelic disorder of SCA 6. PAN and fluctuating symptoms, as seen in our patient, must be carefully examined to see whether or not they can be parts of clinical presentations in SCA 6.

Atrophy↗

PubMed1998

[Serial MRI, SPECT and 1H-MRS findings in a case of herpes simplex encephalitis].

We report herein a case of herpes simplex encephalitis (HSE) in which magnetic resonance imaging (MRI), single photon emission computed tomography (SPECT) and proton magnetic resonance spectroscopy (1H-MRS) were performed sequentially. Both MRI and SPECT demonstrated a lesion on the left temporal lobe in its early stage. However, SPECT seemed more sensitive because it could detect subtle alterations of the blood flow. Hyperperfusion identified by SPECT had returned to normal levels while the abnormal MRI findings still remained. This may indicate that normalization of the blood perfusion precedes the tissue recovery. Contrast enhancement using Gd-DTPA was observed along the surface of the cerebral cortex on MRI, but that involved only part of the hyperperfusion areas depicted with SPECT. In the affected left temporal lobe, 1H-MRS exhibited reduction of N-acetyl-asparate (NAA), and an elevated lactate level. The former represented the neuronal loss, and the latter indicated impairment of oxidative metabolism. Furthermore, alterations of NAA/creatine (Cr) and choline (Cho)/Cr ratios were also observed in the seemingly normal right temporal lobe. Those ratios returned to nearly normal levels in accordance with the patient's clinical recovery. Subsequently, our results indicate that 1H-MRS might be a very useful tool in qualifying the tissue damage and possibly estimating the prognosis.

Encephalitis, Viral↗

PubMed1998

[A study of sialylated carbohydrate antigen in patients with benign bronchopulmonary disease].

We studied the levels of carbohydrate antigen (CA 19-9, SLX, CA 50, Span-1, and Dupan-2) in serum, bronchoalveolar lavage fluid, and tissue from patients with benign bronchopulmonary disease. Patients had bronchiectasis, healed pulmonary tuberculosis, pulmonary fibrosis, or other diseases. Bronchoalveolar lavage fluid levels and immunohistochemical findings for lung tissue samples, in the absence of digestive and other diseases, suggested that elevated serum sialylated Lewis(A) (CA 19-9, CA 50, and Span-1) and Lewis(X) (SLX) antigen in patients with benign broncho-pulmonary disease are due to marked production of sialylated carbohydrate antigen in respiratory bronchioles. Common features of patients with benign bronchopulmonary disease include elevated serum carbohydrate antigen levels and bronchiectasis.

Aged↗

PubMed1998

Features of spontaneous improvement in syringomyelia with low-situated cerebellar tonsils.

We analysed four patients who showed spontaneous improvement among the 19 nonsurgically treated cases of syringomyelia with low-situated cerebellar tonsils who visited our outpatient clinic. MR images both before and after improvement were available for two of these patients; CT-myelography before improvement and MR images after improvement were used for two patients. Consequently, we were able to abstract several features from detailed and precise neurological and radiological evaluations of these patients. These features consisted of mild (rather than severe) disability, as well as three radiological features--a rounded shape of the lower edge of the cerebellar tonsils, a low tightness of the foramen magnum, an elevation of the tonsils during the course of the disease. Results of our radiological analyses were consistent with the theories proposed for the pathogenesis of syringomyelia in the light of the CSF flow around the foramen magnum. We propose that the features we have isolated are useful in determining treatment policies and prognoses of patients with syringomyelia, accompanied by low-situated cerebellar tonsils.

Adult↗

PubMed1997

Tumor necrosis factor enhancement of transient outward potassium currents in cultured rat cortical neurons.

The effect of recombinant human tumor necrosis factor-alpha (TNF) on voltage-gated membrane currents of cultured neurons derived from embryonic rat cerebral cortex was studied using the whole-cell patch-clamp technique. Treatment of neurons with TNF resulted in an increase in outward potassium current density, dependent upon the concentration of TNF and the incubation time, without affecting other membrane currents such as barium and N-methyl-D-aspartate (NMDA). Long exposures (12-48 hr) to TNF (10-100 ng/ml) increased transient outward potassium current (A-current) density without affecting the parameters of activation and inactivation of the current. Prolonged exposures to TNF diminished its increasing effect on the A-current. Since the increase of A-current density induced by TNF is inhibited by both the anti-TNF receptor antibody and cycloheximide treatment, the effect of TNF might be mediated through receptors and by de novo synthesis of the channel protein itself and/or modulating proteins associated with the channel activities. Results indicate that phosphatidylcholine-specific phospholipase C and protein kinase C, but not ceramide, are involved in the signal transduction. In toxicological experiments, TNF had no neurotoxicity. Moreover, a 12 hr pretreatment of TNF protected neurons against NMDA-induced neurotoxicity. This protective effect of TNF was cancelled by 4-aminopyridine, an A-current blocker, suggesting that the increase of A-current densities induced by TNF contributes to the neuroprotection.

Animals↗

PubMed1997

Kidney-specific expression of a novel mouse organic cation transporter-like protein.

Using the signal sequence trap method, we have cloned a novel 12-membrane-spanning transporter-like protein, termed renal-specific transporter (RST), from the mouse kidney. RST is a 553-amino-acid protein highly homologous to recently cloned organic cation transporters, e.g. it is 30% identical to rat organic cation transporter I at the amino acid level. Northern blot analysis has revealed that the RST gene is expressed abundantly and specifically in the kidney. In situ hybridization analysis has shown that RST gene expression is restricted to the renal proximal tubule, where various organic cations such as endogenous catecholamines and choline or clinically used cationic drugs are known to be actively excreted.

Amino Acid Sequence↗

PubMed1997

Autosomal dominant spastic paraplegia linked to chromosome 2p: clinical and genetic studies of a large Japanese pedigree.

Autosomal dominant spastic paraplegia (ADSP) is a genetically heterogenous disorder. To date, 3 loci of ADSP have been identified on chromosome 2p, 14q, and 15q, but specific gene mutations remain unknown. To determine the genetic background of ADSP in the Japanese, we studied a large 3-generation pedigree, clinically and genetically. Of the 36 individuals clinically examined, 15 were affected. The main feature in the affected individuals was a slowly progressive spastic paraplegia, associated with upper limb hyperreflexia (58%), reduction of vibration sense (27%) and bladder disturbance (13%). Age at onset ranged from 13 to 50 years with a mean of 30.3 +/- 14.2 (SD). There were 6 parent-child pairs with anticipation and at least 3 others with 'anti-anticipation'. Linkage with 14q and 15q ADSP loci was excluded, and a highly significant lod score was obtained only in the case of the 2p locus (Zmax = 3.53 for D2S400/D2S352, at theta = 0.00). Our study is the first to confirm the existence of 2p-linked ADSP in the Japanese. There is a significant variety in age at onset and disease severity in these 2p-linked families, but the implication for underlying ADSP mutation is not clear.

Adolescent↗

PubMed1997

Somatodendritic localization of phosphorylated tau in neonatal and adult rat cerebral cortex.

We studied the distribution of phosphorylated tau (p-tau) in neonatal and adult rat cerebrum using monoclonal antibodies that recognize distinct tau epitopes in a phosphorylation-dependent manner. In neonatal cortex, p-tau was detected in the apical dendrites and somata of pyramidal neurons as well as in axons. In adults, p-tau was present predominantly in neuronal somata and dendrites and, to a lesser extent, in axons, whereas tau-1, that recognizes a dephosphorylated tau epitope, immunolabeled neuropil and axons, and not the neuronal somata and dendrites. These results suggest that tau phosphorylated at multiple sites is present in somatodendritic compartments of rat cortical neurons throughout life, and that phosphorylation may be one of the determinants for the compartmentalization of tau in the brain.

Animals↗

PubMed1997

Clonal HTLV-I-infected CD4+ T-lymphocytes and non-clonal non-HTLV-I-infected giant cells in incipient ATLL with Hodgkin-like histologic features.

Lymph nodes from the incipient or early neoplastic phase of adult T-cell leukemia/lymphoma (ATLL) histologically resemble Hodgkin's disease. Integrated proviral human T-lymphotrophic virus type I (HTLV-I) has been demonstrated in such lesions. We studied 18 patients with this disease, and about half of the cases developed typical ATLL within 2 or 3 years. In all cases, either mono- or oligoclonal cell populations with proviral HTLV-I DNA were detected by Southern blot analysis and/or inverse polymerase chain reaction (IPCR). In addition, either a mono- or oligoclonal rearrangement of T-cell receptor genes was demonstrated. Giant cells with Reed-Sternberg-like histological features revealed CD15 and CD30 positivity. The background infiltrating lymphocytes represented either no or only minimal nuclear abnormalities with a CD4+ T-cell phenotype. In less than half of all cases, Epstein-Barr virus (EBV) infected the giant cells. A mixed EBV-A and -B type was found in 3, and a multiple genotype of EBV lymphocyte-determined membrane antigen (LYDMA) was found in 6 cases. These results could have been due to the immunodeficient status of the patients. A single-cell PCR of the giant cell, B cell, CD4+ or CD8+ T cells could be performed after cell sorting in 4 cases. HTLV-I infection was frequently found in the CD4+ T cells, but in neither the giant cells nor the B cells. The CD4+ T cells exhibited clonality. The giant cells showed various PCR products of IgH, and also expressed recombination activating genes (RAG). In summary, the giant cells were reactive cells, which resembled the immature B-lineage cells, while HTLV-I infected the CD4+ T cells, which demonstrated clonality. Based on these above findings, we consider CD4+ cells to play an important role in ATLL tumorigenesis.

Adolescent↗

PubMed1997

Direct involvement of the ubiquitin-conjugating enzyme Ubc9/Hus5 in the degradation of IkappaBalpha.

The NF-kappaB/Rel proteins are sequestered in the cytoplasm in association with IkappaBalpha. In response to external signals, IkappaBalpha is phosphorylated, multi-ubiquitinated, and degraded by proteasomes, thereby releasing NF-kappaB/Rel proteins to migrate to the nucleus. We have cloned a mouse ubiquitin-conjugating enzyme (mE2), which associates with IkappaBalpha. mE2 is homologous to the yeast Ubc9/Hus5 ubiquitin-conjugating enzyme. A transdominant-negative mutant of mE2 had no effect on phosphorylation of IkappaBalpha, but delayed its degradation. Correspondingly, tumor necrosis factor-alpha-inducible NF-kappaB activity was diminished. We propose that mE2 is directly involved in the ubiquitin conjugation of IkappaBalpha, a pivotal step in its degradation pathway.

Amino Acid Sequence↗

PubMed1997

Calumenin, a Ca2+-binding protein retained in the endoplasmic reticulum with a novel carboxyl-terminal sequence, HDEF.

We have identified and characterized a cDNA encoding a novel Ca2+-binding protein named calumenin from mouse heart by the signal sequence trap method. The deduced amino acid sequence (315 residues) of calumenin contains an amino-terminal signal sequence and six Ca2+-binding (EF-hand) motifs and shows homology with reticulocalbin, Erc-55, and Cab45. These proteins seem to form a new subset of the EF-hand protein family expressed in the lumen of the endoplasmic reticulum (ER) and Golgi apparatus. Purified calumenin had Ca2+-binding ability. The carboxyl-terminal tetrapeptide His-Asp-Glu-Phe was shown to be responsible for retention of calumenin in ER by the retention assay, immunostaining with a confocal laser microscope, and the deglycosylation assay. This is the first report indicating that the Phe residue is included in the ER retention signal. Calumenin is expressed most strongly in heart of adult and 18.5-day embryos. The calumenin gene (Calu) was mapped at the proximal portion of mouse chromosome 7.

Amino Acid Sequence↗

PubMed1997

D-aspartic acid localization during postnatal development of rat adrenal gland.

Developmental changes in cellular localization of D-aspartic acid (D-Asp) were investigated in rat adrenal gland with polyclonal anti-D-Asp antibody. At 1 and 3 weeks of age, immunoreactivity (IR) toward this amino acid was intense in the cytoplasm of cells in the zona fasciculata (ZF) and zona reticularis (ZR) of the adrenal cortex but was less so in the zona glomerulosa (ZG). Conversely at 8 weeks of age, intense IR was observed in the ZG and less in the ZF and ZR. In the adrenal medulla, IR was evident in large clusters of cells which were identified as adrenaline-storing cells. The emergence of D-Asp in specific types of cells at distinct periods of development of rat adrenal gland suggests that this amino acid may have a physiological role in the maturation of the organ.

Adrenal Cortex↗

PubMed1997

Cloning of human chromosome 17-specific cDNAs using representational difference analysis and human-mouse hybrid cells.

We employed cDNA representational difference analysis (RDA) with human-mouse somatic hybrid cells containing human chromosome 17 and obtained several cDNA clones specific for this chromosome. A cDNA library from PHA-stimulated T cells was screened with unknown cDNA clones obtained by RDA as probes. Subsequently, 1 complete gene and 1 partial cDNA clone were obtained. Our successful result implies that this subtractive amplification technique with hybrid cells will be a useful aid in positional cloning in large-spanning regions.

Amino Acid Sequence↗