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T Kitamura

Publications and source records attributed to T Kitamura.

At least 397 records · Page 22Linked to original sources
PubMed1995

Integrity of myosin light chain kinase is essential for Ito cell contraction.

Hepatic sinusoidal Ito cells (fat storing cells) are believed to play a regulatory role on hepatic sinusoidal blood flow through their contraction. The detailed mechanism of contraction of Ito cells, however, is still unknown. The present study was undertaken to clarify the effect of new myosin light chain kinase inhibitor, wortmannin, on Ito cell contraction. Ito cells prepared from rat liver were cultured for 4 days before the study. The contraction of Ito cells, which was monitored and analysed by time-lapse video tape recording, was triggered by addition of endothelin-1. Wortmannin pretreatment for 1 h inhibited endothelin-induced Ito cell contraction dose-dependently. Therefore, the integrity of the actomyosin system is essential for Ito cell contraction and normal sinusoidal blood flow.

Androstadienes↗
PubMed1995

Genetic and clinical correlates of season of birth of schizophrenics.

The genetic and clinical characteristics of 55 patients with schizophrenia and 138 control patients (with major psychiatric disorders), were studied in relation to the season of birth. The morbid risk (MR) of schizophrenia was significantly higher among relatives of the schizophrenic probands born in Spring than among those of the psychiatric controls born in the same season. The MR of schizophrenia was also significantly higher among relatives of schizophrenic probands born in Winter or Spring (6.9%) than in those of schizophrenic probands born in Summer or Autumn (0%). Among the schizophrenic cases, Winter births were marginally related to the paranoid subtype, whereas other clinical variables showed no clear relationship with the season of birth.

Adult↗
PubMed1995

Increased incidental detection and reduced mortality in renal cancer--recent retrospective analysis at eight institutions.

A retrospective survey of renal cell carcinoma between 1975 and 1993 at eight collaborating institutions was conducted with special reference to the incidental detection and mortality of renal cancer. The analysis demonstrated a recent dramatic increase in the frequency of incidental renal cancer, which now comprises two-thirds of all renal cancers, and a simultaneous recession in non-incidental or suspected renal cancer. Incidental renal cancer has remained unchanged during the last decade as far as patient demographics, occasion and method of detection, and the degree of tumor extension are concerned. On the other hand, the annual number of deaths from renal cancer has significantly decreased, and kidney-sparing surgery has been more frequently performed. These results indicate that incidental renal cancers are now in the majority, and earlier detection may contribute to improving the mortality and morbidity from the disease as a whole.

Aged↗
PubMed1995

Accuracy of prostatic volume calculation in transrectal ultrasonography.

BACKGROUND: Estimation of the prostatic volume by transrectal ultrasonography is now widely used to evaluate the effect of conservative treatment and to improve the specificity of prostate specific antigen. Accurate measurement of prostatic volume is necessary for the calculation of prostate specific antigen density (PSA/prostatic volume ratio). METHODS: Three dimensional models of the prostatic contour were constructed from transrectal ultrasonotomograms taken at 5 mm intervals in 20 cases. Using these models, the accuracy of ellipsoid volume calculation and prolate ellipse volume calculation were examined. For prolate ellipse volume calculation, prostatic length was measured in two ways; length (Lv) vertical to the transverse section, and length (Lp) parallel to the prostatic urethra. RESULTS: Ellipsoid volume calculation showed errors of about 20%. Moreover, ellipsoid volume calculation fluctuated markedly (up to 50%) in accordance with the change of the scanning angle of the transverse section. The error of prolate ellipse volume calculation using Lp for length increased by an average of 25% as the angle moved away from the perpendicular. The prolate ellipse volume calculation using Lv for length was the most reliable method. The degree of error was least dependent on the angle between the plane and the axis. CONCLUSION: Although prolate ellipse volume calculation was more accurate than ellipsoid volume calculation, it is essential to have the three axes cross at right angles to obtain an accurate value by the prolate ellipse volume calculation.

Humans↗
PubMed1995

Parent-to-child transmission is relatively common in the spread of the human polyomavirus JC virus.

JC polyomavirus (JCV), the causative agent of progressive multifocal leukoencephalopathy, is ubiquitous in the human population, infecting children asymptomatically and then persisting in renal tissue. In most adults, renal JCV replicates and the progeny are excreted in urine. We used this urinary JCV to elucidate the routes of JCV transmission. A 610-bp JCV DNA region (IG region) encompassing the 3'-terminal sequences of both T-antigen and VP1 (major capsid protein) genes was amplified by means of PCR from urine specimens collected from all members of seven families. JCV strains were then unequivocally identified by the nucleotide sequences of the amplified IG regions. We could identify 18 distinctive JCV strains from 27 individuals. Different JCV strains were detected from all unrelated persons. However, the same viral strain was detected from one (four families), two (one family), or three offspring (one family) as well as from the fathers (three families) or from the mothers (three families). In total, the JCV strains detected in half of the JCV-positive children were identified in their parents. Since most humans are infected during childhood, these findings indicated that JCV is transmitted frequently from parents to children. We roughly estimated that 50% of JCV transmission occurs by this route and that the other 50% occurs outside the family.

Adult↗
PubMed1995

Symptoms of psychoses. A factor-analytic study.

BACKGROUND: The literature on the statistical analysis of symptoms of psychoses was limited to positive and negative symptoms in schizophrenia. The present study explored the relationship between positive and negative symptoms as well as affective symptoms in a wider category of psychotic disorders. METHOD: The symptoms of 584 psychiatric patients, consecutively admitted to any of the 95 mental hospitals in Japan, were studied. They manifested at least one of the following: (a) delusions, (b) hallucinations, (c) formal thought disorder, (d) catatonic symptoms, or (e) negative (defect) symptoms. RESULTS: Factor analysis yielded five factors interpretable as (a) manic symptoms, (b) depressive symptoms, (c) negative (defect) symptoms and formal thought disorders, (d) positive (psychotic) symptoms, and (e) catatonic symptoms. CONCLUSION: These results suggest that although major symptoms seen among psychotic patients can be categorised into positive, negative, manic, and depressive groups, corresponding to current knowledge of phenomenology, catatonic symptoms constitute a discrete syndrome, while formal thought disorders merge into the negative syndrome.

Adolescent↗
PubMed1995

Isolation and characterization of a hantavirus from Rattus norvegicus in a residential area of Nagoya City, Japan.

The prevalence of antibodies to hantavirus among Rattus norvegicus in Nagoya city was examined during the period from 1986 to 1993. Eight sera of 675 were antibody positive in an indirect fluorescent antibody test. Antibody positive rats were found in 1988, 1990, 1991 and 1992 and the numbers of rats were 1, 1, 3 and 3, respectively. A hantavirus strain was isolated from a rat captured in 1990 at a residential area adjoining to a pier in Nagoya port. The virus strain, named NR-9, was identified antigenically as the Seoul type of hantavirus in a neutralization test. Suckling rats inoculated with NR-9 strain survived, while those with SR-11 strain succumbed. A difference between the virulence of strains, NR-9 and SR-11 was demonstrated.

Animals↗
PubMed1995

Regeneration of axons in transection of the carp spinal cord.

Axonal regeneration in the central nervous system (CNS) was investigated in the fine structural and histochemical aspects using carp spinal cord, which was completely transected at the level of the dorsal fin. Fusion of the transection region and the regeneration of axons already began to be recognized 26 days after operation by electron microscopy. At 115 days after operation, the rostral and caudal parts of the transected spinal cord were completely connected by the regenerating nervous tissue, which contained numerous axons among the ependymal and glial processes. Horseradish peroxidase (HRP), which was injected in the spinal cord at the portion caudal to the transection site was detected in the cytoplasm of large neurons located in the reticular formation of midbrain. This demonstrates that these long axons were regenerated passing through the ablation gap 151-204 days after operation. These findings indicate that regenerating axons in the carp spinal cord can pass through the glial scar formed in the transected portion, which is considered to be the main obstacle for the prolongation of axons in the mammalian CNS. Many regenerating axons, both unmyelinated and myelinated, were observed being in contact directly with the cell membrane of the ependymal as well as astroglial cells. This indicates that neither ependymal nor glial cells play a role as an obstacle for elongation of axons in the carp spinal cord. Numerous GFAP (glial fibrillary acidic protein) positive intermediate filaments were observed in the cell bodies and cytoplasmic processes of both ependymal cells and astroglia.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

Immunological study of anti-M2 in antimitochondrial antibody-negative primary biliary cirrhosis.

We investigated the specificity of various autoantibodies in antimitochondrial antibody (AMA)-negative patients with primary biliary cirrhosis (PBC). We examined sera from 144 patients with PBC, 17 of whom were AMA negative by indirect immunofluorescence. The AMA-negative group showed a significantly higher positivity for smooth muscle antibody, but not for antinuclear antibody, as compared with the AMA-positive group. IgG class anti-PDH by enzyme-linked immunosorbent assay (ELISA) were detected in 13% of the AMA-negative group. However, all PBC patients showed positive IgG, IgA, and/or IgM class anti-M2 to the four M2 proteins by immunoblotting. These results suggest that the detection of IgG and IgM class anti-PDH and that of antibodies to the four M2 proteins increases the positivity of this ELISA method, and that detection of IgG, IgA, and IgM class anti-M2 to the four M2 proteins by immunoblotting is useful in diagnosing AMA-negative patients with PBC.

Adult↗
PubMed1995

Expression of transglutaminase I in human anagen hair follicles.

The expression of the transglutaminase I in human anagen hair follicles was studied by an immunohistochemical staining. In the bulbar and suprabulbar portions of anagen hair follicles, transglutaminase I was detected on the hair cuticle and the three layers of the inner root sheath. Subsequently, the positive staining became translocated to the inner site of the outer root sheath in the middle part of the hair follicle. In the upper portion of the hair follicle transglutaminase I was detected in the internal part of the outer root sheath and the surface epidermis. Therefore, it was suggested that the expression of transglutaminase I might be closely associated with the terminal keratinization in the anagen hair follicles.

Adult↗
PubMed1995

[Evaluation of reliability of IPSS by 24-hour uroflowmetry].

BACKGROUND: Although the international prostate symptom score (IPSS) is now often used to assess the symptoms of BPH, whether or not patients answer the questions correctly has not been validated objectively. METHODS: Reliability of IPSS was evaluated by 24-hour uroflowmetry in 20 hospitalized male patients. Six of them had prostatic hypertrophy or cancer, and the evaluation was performed before and after TURP or hormonal therapy in these six patients. The objective scores for frequency and nocturia were obtained from the time recorded on IC card. The objective score for intermittency was calculated from the uroflow curves. RESULTS: The answer about frequency was not correct compared with the objective scores for frequency. The answers about nocturia and intermittency were almost the same as the corresponding objective scores. The answer for weak stream correlated with the average of peak flow rate. However, the threshold of peak flow rate for "weak stream" fluctuated markedly before and after the treatment in the same individuals. The answer for hesitancy had no correlation with the hesitation time. Patients seemed to understand the question translated in Japanese as "have you need force to urinate?" CONCLUSION: Before wider use of IPSS in Japan, the correct translation of the questions and verification of the usefulness of the questions in large number of Japanese patients seem necessary.

Humans↗
PubMed1995

A case of acute lymphoblastic leukemia accompanied with the production of parathyroid hormone-related protein.

Hypercalcemia accompanied with malignant tumors is generally classified into two categories, namely with or without bone metastasis. As for the latter, bone resorption-stimulating factors produced by tumor cells, such as parathyroid hormone-related protein (PTHrP), show hormone-like effects and promote a bone resorption. Many cases have been reported regarding the production of TPTHrP in adult T cell leukemia (ATL), but few have been reported with acute lymphoblastic leukemia (ALL). We report here a similar case with ALL. A 12-year-old male presented with fever, petechiae and thrombocytopenia, and was diagnosed as ALL. We started the induction therapy and confirmed complete remission. Later, he relapsed 3 times without symptoms apart from hypercalcemia at the beginning. Elevation of the serum calcium level followed by a rise of lymphoblastic cells was recognized. Bone metastasis was excluded since bone mineral density and serum mid region PTH were normal and no abnormal findings were noticed on X rays and 99mTc bone scintigraphy. However, his urinary PTHrP level was high, and his lymphoblastic cells staining immunocytochemically with the monoclonal antibodies against the C-terminal region of PTHrP showed a positively brownish color. Finally, he died of pulmonary aspergillosis. Hypercalcemia was not related to serum PTH or bone metastasis. ATL viral infection reported as a cause of PTHrP production was also excluded from several experimental data. Therefore, we concluded that lymphoblastic cells directly produced PTHrP, and that this PTHrP played an important role in the induction of hypercalcemia.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1995

A novel RING-H2 motif protein downregulated by axotomy: its characteristic localization at the postsynaptic density of axosomatic synapse.

Axonal injury and its repair are common and basic neuropathological processes in the CNS, and are composed of a complex of events in a molecular term. In order to get a comprehensive understanding of these processes, we isolated several known and unknown genes which were up-or downregulated in the facial nucleus after transection of the facial nerve by a subtractive/differential screening. Among them, we focus on one downregulated gene, named Neurodap1, because this gene encodes a novel protein carrying the RING-H2 sequence motif categorized in the zinc finger family. Immunoelectron microscopic analysis revealed that the protein encoded by Neurodap1, Neurodap1, was distributed mainly on the cytoplasmic side of the membranes constituting endoplasmic reticulum and Golgi apparatus, supporting the notion of a previously postulated function of RING-H2 motif proteins, that is, involvement in the protein sorting machinery. More interestingly, Neurodap1 was also bound to the postsynaptic density (PSD) region of axosomatic synapses. This fact suggests that Neurodap1 is associated with a specific system sorting proteins to PSD. Therefore, Neurodap1, a newly identified protein as an axotomy-suppressed gene product, might play a significant role in synaptic communication and plasticity through the control of the formation of PSD for maintaining vital functions of nerve cells.

Amino Acid Sequence↗
PubMed1995

Different features of Ca2+ oscillations in differentiated and undifferentiated hepatocyte doublets.

Cytosolic free Ca2+ ([Ca2+]i) oscillations are postulated to play a critical role in cellular proliferation. By using doublets of normal rats (NR) and those 18 hours after two-thirds hepatectomy (PHR), we investigated cytosolic free Ca2+ ([Ca2+]i) responses in liver regeneration. Normal rat hepatocyte doublets that retain their bile canaliculi are polarized and well differentiated. PHR doublets, which also retain their bile canaliculi, were characterized as undifferentiated by (1) decreased canalicular secretion of fluorescein-isothiocyanate-labeled glycocholate; (2) increased labeling index of hepatocytes in BrdU staining (approximately 30%); and (3) impaired transfer of fluorescent dye injected into one cell of the pair to the other. Addition of phenylephrine to NR and PHR doublets in the presence of extracellular Ca2+ resulted in [Ca2+]i oscillations or a nonoscillatory-sustained increase in [Ca2+]i followed by a gradual return to the baseline. Extracellular Ca2+ was not required for [Ca2+]i oscillations but was necessary for a sustained increase in [Ca2+]i. Simultaneous addition of prazosin, alpha 1-receptor blocker, to doublets immediately abolished these [Ca2+]i responses. The [Ca2+]i level in each of the adjacent cells was synchronous in sustained increase in [Ca2+]i but asynchronous in [Ca2+]i oscillations. As the phenylephrine concentration was increased (1 to 100 mumol/L), oscillations were replaced by a sustained increase in [Ca2+]i in NR doublets. In contrast, in PHR doublets, oscillations remained, whereas the frequency of oscillations increased in a dose-dependent manner. These results indicate that the mechanisms of phenylephrine-evoked [Ca2+]i responses are different in differentiated and undifferentiated doublets and that the frequency modulation of [Ca2+]i oscillations may be involved in the intracellular signal transduction in the cellular proliferation process during liver regeneration.

Adrenergic alpha-Antagonists↗
PubMed1995

The Comprehensive Assessment List for Affective Disorders (COALA): a polydiagnostic, comprehensive, and serial semistructured interview system for affective and related disorders.

This supplement describes the development and structure of the Comprehensive Assessment List of Affective Disorders (COALA) system, which was recently developed for a collaborative follow-up study of a broad spectrum of affective disorders in Japan and which consists of a series of semistructured interviews for affective and related disorders. The COALA distinguishes itself from the extant semistructured interviews by being able to provide polydiagnostic, comprehensive and serial assessments. It is polydiagnostic because it derives diagnoses according to 29 historical and modern diagnostic systems through computer algorithms. It is comprehensive because it not only depicts the symptoms profile and rates their severity according to various endogenicity indices and severity rating scales but also measures, in the psychosocial domain, the life events and their characteristics. In addition, it has sections for past illnesses and family history. It is serial because the system includes follow-up semistructured interviews that can be administered monthly and that monitor changes in the psychopathological and psychosocial features. The theoretical underpinnings of the COALA system, especially its polydiagnostic approach to a broad spectrum of affective disorders and its treatment of psychosocial factors, are discussed in view of recent proposals for the future nosological research. The findings of the interrater reliability study (n = 107) are also presented, with satisfactory to excellent results for almost all of the psychopathological and psychosocial variables, all of the composite severity ratings and most of the polydiagnostic evaluations.

Female↗
PubMed1994

1-Phosphatidylinositol 3-kinase activity is required for insulin-stimulated glucose transport but not for RAS activation in CHO cells.

Insulin stimulation drives the formation of a complex between tyrosine-phosphorylated insulin receptor substrate 1 (IRS-1) and 1-phosphatidylinositol 3-kinase (PI 3-kinase; ATP:1-phosphatidyl-1D-myo-inositol 3-phosphotransferase, EC 2.7.1.137), a heterodimer consisting of regulatory 85-kDa (p85) and catalytic 110-kDa (p110) subunits. This interaction takes place via the phosphorylated YMXM motifs of IRS-1 and the Src homology region 2 (SH2) domains of p85. In this study, the stable overexpression in a Chinese hamster ovary (CHO) cell line of a mutant p85 alpha (delta p85) protein, which lacks a binding site for p110, disrupted the complex formation between IRS-1 and the catalytic subunit of PI 3-kinase in intact cells during insulin stimulation. Activation of insulin receptor kinase and the tyrosine phosphorylation of IRS-1 remained unaffected. In this cell line, both insulin-stimulated accumulation of phosphatidylinositol 3,4,5-trisphosphate and the insulin-stimulated glucose uptake due to the translocation of GLUT1 glucose transporters were markedly impaired, whereas neither phorbol 12-myristate 13-acetate-stimulated glucose uptake nor the insulin-stimulated activation of RAS was impaired. These results suggest that PI 3-kinase is required for glucose transport in insulin signaling in CHO cells.

Animals↗
PubMed1994

Signal transduction pathways from insulin receptors to Ras. Analysis by mutant insulin receptors.

We have examined the involvement of insulin receptor (IR) substrate-1 (IRS-1) and/or Shc in the upstream of Ras activation in insulin signaling using Chinese hamster ovary (CHO) cell lines overexpressing wild-type (CHO-IR) cells) or mutant insulin receptors. In CHO-IR cells, insulin rapidly phosphorylated IRS-1 and Shc at tyrosine residues and stimulated the formation of the active GTP-bound Ras (Ras.GTP). In contrast, a CHO cell line overexpressing the kinase-negative mutant insulin receptor substituting Arg1018 for Lys1018 was unable to tyrosine-phosphorylate IRS-1 and Shc and failed to activate Ras in response to insulin. A CHO cell line overexpressing the mutant insulin receptor, substituting Ala960 for Tyr960 and which was known to exhibit impaired tyrosine phosphorylation of IRS-1 and biological effects evoked by insulin, showed severely impaired insulin-dependent tyrosine phosphorylation of Shc and moderately impaired activation of Ras. Another cell line overexpressing the mutant insulin receptor, lacking 82 amino acids of the C terminus of beta-subunit and which was recently reported to retain normal insulin-dependent tyrosine phosphorylation of IRS-1, showed slightly impaired Ras activation at 10(-7) M insulin with severely reduced tyrosine phosphorylation of Shc protein. Furthermore, insulin did not induce the association of tyrosine-phosphorylated IRS-1 and Shc in CHO-IR cells. These results suggest that Shc and IRS-1 lie in the separate signaling pathways and that the tyrosine phosphorylation of IRS-1 with or without some low level of Shc phosphorylation may be enough to stimulate the submaximal accumulation of Ras.GTP complex and may need synergistically the higher level of tyrosine phosphorylation of Shc to induce the full activation of Ras in insulin signaling.

Animals↗