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K Nomiyama

Publications and source records attributed to K Nomiyama.

At least 19 recordsLinked to original sources
PubMed2005

Acquired lesions of the corpus callosum: MR imaging.

In this pictorial review, we illustrate acquired diseases or conditions of the corpus callosum that may be found by magnetic resonance (MR) imaging of the brain, including infarction, bleeding, diffuse axonal injury, multiple sclerosis, acute disseminated encephalomyelitis, Marchiafava-Bignami disease, glioblastoma, gliomatosis cerebri, lymphoma, metastasis, germinoma, infections, metabolic diseases, transient splenial lesion, dilated Virchow-Robin spaces, wallerian degeneration after hemispheric damage and focal splenial gliosis. MR imaging is useful for the detection and differential diagnosis of corpus callosal lesions. Due to the anatomical shape and location of the corpus callosum, both coronal and sagittal fluid-attenuated inversion recovery images are most useful for visualizing lesions of this structure.

Brain Diseases↗
PubMed2005

Brainstem and cerebellar changes after cerebrovascular accidents: magnetic resonance imaging.

We illustrate the various types of secondary degeneration in the brainstem and/or cerebellum detected on magnetic resonance (MR) images obtained after cerebrovascular accidents. The changes include: (a) ipsilateral nigral degeneration after striatal infarction; (b) Wallerian degeneration of the pyramidal tract in the brainstem after supratentorial pyramidal tract or motor cortex injury; (c) Wallerian degeneration of the corticopontine tract in the brainstem after frontal lobe infarction; (d) ipsilateral brainstem atrophy and crossed cerebellar atrophy due to an extensive supratentorial lesion; (e) ipsilateral superior cerebellar peduncle atrophy, contralateral rubral degeneration, contralateral inferior olivary degeneration and ipsilateral cerebellar atrophy after dentate nucleus hemorrhage; (f) ipsilateral inferior olivary degeneration after pontine tegmentum hemorrhage; (g) bilateral wallerian degeneration of the pontocerebellar tracts after ventromedial pontine infarction or basis pontis hemorrhage; and (h) ipsilateral cerebellar atrophy after middle cerebellar peduncle hemorrhage.

Adult↗
PubMed2002

Lead induced increase of blood pressure in female lead workers.

AIMS: Although lead exposure has, in the absence of mathematical modelling, been believed to elevate blood pressure in females, it is necessary to clarify the relation between lead and blood pressure by eliminating confounding factors in the analysis. METHODS: Blood lead was measured in 193 female workers, including 123 lead exposed workers. Possible confounding factors were controlled by multiple regression analyses. RESULTS AND CONCLUSIONS: Blood lead above 40 micro g/dl was found to be the most potent factor for elevating systolic/diastolic blood pressure. Aging, urine protein, and plasma triglyceride also contributed to systolic/diastolic/pulse pressure increase, but hypertensive heredity did not. Data suggested that lead induced changes in lipoprotein metabolism may play an important role in the lead induced blood pressure increase in female workers.

Adolescent↗
PubMed2001

A novel recombinant adeno-associated virus vaccine induces a long-term humoral immune response to human immunodeficiency virus.

Recombinant adeno-associated virus (AAV) has attracted tremendous interest as a promising vector for gene delivery. In this study we have developed an HIV-1 vaccine, using an AAV vector expressing HIV-1 env, tat, and rev genes (AAV-HIV vector). A single injection of the AAV-HIV vector induced strong production of HIV-1-specific serum IgG and fecal secretory IgA antibodies as well as MHC class I-restricted CTL activity in BALB/c mice. The titer of HIV-1-specific serum IgG remained stable for 10 months. When AAV-HIV vector was coadministered with AAV-IL2 vector, the HIV-specific cell-mediated immunity (CMI) was significantly enhanced. Boosting with AAV-HIV vector strongly enhanced the humoral response. Furthermore, the mouse antisera neutralized an HIV-1 homologous strain, and BALB/c mice immunized via the intranasal route with an AAV vector expressing the influenza virus hemagglutinin (HA) gene showed protective immunity against homologous influenza virus challenge. These results demonstrate that AAV-HIV vector immunization may provide a novel and promising HIV vaccination strategy.

AIDS Vaccines↗
PubMed2001

Calcium ions stabilize a protein structure of hemolytic lectin CEL-III from marine invertebrate Cucumaria echinata.

CEL-III, a galactose/N-acetylgalactosamine (Gal/GalNAc)-specific lectin purified from a marine invertebrate, Cucumaria echinata, has a strong hemolytic activity, especially toward human and rabbit erythrocytes in the presence of Ca2+. We evaluated the role of Ca2+ in hemagglutinating and hemolytic activities of CEL-III. We found that Ca2+ is closely associated with both activities of CEL-III. The fluorescence spectra of CEL-III upon binding to Ca2+ were measured. The result showed a structural change of CEL-III in the presence of Ca2+. The structural change of CEL-III upon Ca2+ binding was further demonstrated by stabilization against urea denaturation and by insusceptibility to protease digestions. CEL-III was completely unfolded at a low concentration of 2 M urea, while CEL-III complexed with Ca2+ was stable in 6 M urea. As for protease digestions, CEL-III monomer and oligomer were readily digested by trypsin, chymotrypsin, and papain in the absence of Ca2+, while they were insusceptible to the three proteases in the presence of Ca2+. The papain digestion of the decalcified oligomer produced a large C-terminal peptide, suggestting that the C-terminal region of CEL-III may participate in oligomerization of CEL-III as a core domain.

Animals↗
PubMed2001

[A case of lupoid hepatitis satisfying criteria for systemic lupus erythematosus associated with psychosis].

A 26-year-old female was admitted to our hospital because of arthralgia and general fatigue. On examination, she had malar rash and arthritis. Laboratory data revealed AST, ALT and gamma-globulin elevation, antinuclear antibody and double-stranded DNA antibody positivity, and LE cell phenomenon. Liver biopsy showed marked lymphocytic infiltration and slight fibrosis in the portal areas. She was diagnosed with lupoid hepatitis, and also satisfied the criteria for SLE including malar rash, arthritis, immunologic disorder and antinuclear antibody. She was administered prednisolone, after which AST and ALT decreased. She developed psychosis and her electroencephalogram showed diffuse slow waves corresponding to psychosis by SLE. Lupoid hepatitis is frequently associated with various systemic manifestations. However, only a few cases of lupoid hepatitis satisfying the criteria for SLE associated with psychosis have been reported.

Adult↗
PubMed2000

Upregulation of the expression of Fas antigen and Fas ligand in a human submandibular gland ductal cell line by okadaic acid.

Fas receptor is a member of a superfamily of receptors characterized by cysteine-rich motifs in the extracellular domain of the molecule. Binding of Fas ligand to the receptor leads to receptor activation and the induction of intracellular signals that result in apoptotic cell death. In the present study, the expression of mRNA and proteins of Fas receptor and Fas ligand were examined in human submandibular gland ductal (HSG) cells treated with okadaic acid by reverse transcriptase-polymerase chain reaction (RT-PCR) and immunoblot analysis. Six hundred and eighty-two bp of the PCR product of Fas receptor mRNA was detected in HSG cells and a protein with an estimated molecular weight of 58,000 was expressed in HSG cells. Treatment of HSG cells with an agonistic anti-Fas monoclonal antibody resulted in death of HSG cells, indicating that the functional Fas receptor protein is expressed in HSG cells. Fas receptor protein expression stimulated by okadaic acid was elevated in a dose- and time-dependent manner, with maximal expression at 20 nM and 48 h treatment. Fas ligand mRNA was also detected constitutively in HSG cells by RT-PCR. Okadaic acid stimulated the expression of Fas ligand protein in HSG cells in a time-dependent manner, while the expression of the ligand was low in untreated HSG cells. The molecular weight of Fas ligand was estimated as 68,000. An antagonistic anti-Fas ligand monoclonal antibody prevented okadaic acid-induced death in HSG cells in a dose-dependent fashion as determined by WST-1 assay. The results indicate that the expression of Fas receptor and ligand is regulated by protein phosphatase(s) sensitive to okadaic acid and is involved in okadaic acid-induced apoptosis in HSG cells. The results also suggest that the Fas receptor-ligand system might regulate apoptosis in HSG cells.

Antibodies, Monoclonal↗
PubMed2000

Acute effect of cadmium-metallothionein on glucose and amino acid transport across the apical membrane of the rabbit proximal tubule perfused in vitro.

Acute as well as chronic exposure of cadmium (Cd) leads to proximal tubule injury. The exact cellular mechanism of this disorder and whether there is a contribution of cadmium-metallothionein (Cd-MT), a binding protein of Cd, remain unclear. We perfused isolated S2 segments of rabbit nephron, and the deflections of transmural voltage (DeltaV(t)) and apical membrane voltage (DeltaV(a)) on elimination of glucose or alanine from the perfusate were measured for the parameters of activity of Na(+)-glucose and Na(+)-amino acid cotransporters. The effects of Cd-MT or CdCl(2) to either bath or lumen for 10 min on these parameters were examined. We also measured the lumen-to-bath [(14)C]glucose flux. Addition of Cd-MT to lumen suppressed glucose- or alanine-dependent DeltaV(t) and DeltaV(a), as well as baseline V(t) and basolateral membrane voltage (V(b)), at approximately 10 min. [(14)C]glucose flux was inhibited by Cd-MT to lumen. The effects of Cd-MT to bath and CdCl(2) to either lumen or bath were 100-fold less potent than that of Cd-MT to lumen. Luminal Cd-MT immediately suppressed the glucose-dependent DeltaV(a), whereas the baseline V(a) and V(t) were unchanged. The early effect of luminal Cd-MT was simulated by addition of 10(-4) M phloretin. Addition of 10(-4) M ouabain to the bath simulated the later effect of Cd-MT. The protection of SH group by dithiothreitol prevented the early effect of Cd-MT, but not the later effect. We concluded that Cd-MT initially acts directly on Na(+)-glucose and Na(+)-amino acid cotransporters from the lumen by attacking SH group, followed by the later inhibition of Na(+)-K(+)-ATPase after entering the cell from the apical membrane.

Alanine↗
PubMed1999

Mechanism of hepatorenal syndrome in rats of Long-Evans Cinnamon strain, an animal model of fulminant Wilson's disease.

Rats of Long-Evans Cinnamon (LEC) strain were used as a hepatorenal syndrome model of fulminant Wilson's disease. Copper levels in the kidneys increased markedly from 16 to 126 microg Cu/g from 12 to 16 weeks, and remained at the same level at 16 and 19 weeks when the rats suffered from severe renal dysfunction and also at 20 weeks in some other normal rats. The above findings imply that the renal dysfunction may have been induced independently of the copper level in the kidneys. The present study suggested the following mechanism: immediately after copper-induced hepatic dysfunction, plasma copper-metallothionein (CuMT), which was released from the liver, became elevated. The elevation was closely related to the increases in alkaline phosphatase, glucose and amino acids, all in the urine. The above findings suggest that plasma CuMT, which was released from the liver into the blood upon copper-induced hepatic dysfunction, was subsequently filtered at the glomeruli due to its smaller molecular weight, and then caused dysfunction of the brush border membrane of the renal proximal tubules probably after splitting into radical copper and amino acids in acidic vesicles close to the membrane. The critical concentration of plasma CuMT required to induce renal dysfunction was estimated as 1 microg Cu/l.

Animals↗
PubMed1999

Erythrocyte delta-aminolevulinic acid dehydratase genotype and other mechanisms affecting workers' susceptibility to lead.

In this study, the role of delta-aminolevulinic acid dehydratase (ALAD) variants in lead susceptibility was examined. The study subjects comprised 223 male workers, and the relationship between their blood lead level and erythrocyte ALAD activity or plasma/urine delta-aminolevulinic acid level was studied. Leukocyte specimens from 11 workers, whose erythrocyte ALAD activities were as low as one-fifth that of the other normal workers, were subjected to analyses of their ALAD and ALAD alleles. Further, the entire exon fragment of the ALAD gene was analyzed by polymerase chain reaction, and the reaction product was used as a target for direct DNA sequencing. Genomic DNA analysis revealed that all 11 workers had the ALAD allele, whereas the entire ALAD gene analysis failed to indicate other variants, except for the Rsa I site. The depletion in erythrocyte ALAD activity was not found to be caused by the ALAD allele.

Adult↗
PubMed1999

[Cadmium].

Explore the source record for details and available documents.

Cadmium↗
PubMed1998

Plasma cadmium-metallothionein, a biological exposure index for cadmium-induced renal dysfunction, based on the mechanism of its action.

Thirteen rabbits were given subcutaneous cadmium (0.3 mg Cd/kg) daily. The plasma cadmium-metallothionein (CdMT) and the Cd-induced hepatic and renal functions were determined at 0, 5, 8, 11, 12, 13 and 14 weeks. Hepatic dysfunction, an elevated plasma CdMT and renal dysfunction were detected mostly between 12 and 14 weeks. The hepatic dysfunction parameters were closely related with the plasma CdMT, which was then found to correlate with the renal dysfunction parameters. All the above findings suggest the following mechanism for the Cd-induced renal dysfunction: hepatic CdMT is released into the plasma upon the Cd-induced hepatic dysfunction, and then excess plasma CdMT, whose concentration is proportional to the CdMT in the renal proximal tubular lumen, induces renal dysfunction. The critical concentration of plasma CdMT to induce renal dysfunction was estimated as 80 microg Cd/l. The plasma CdMT is proposed therefore as a biological exposure index for the Cd-induced renal dysfunction, based on the mechanism of its action.

Animals↗
PubMed1998

Prevalence of hepatitis C virus antibody in patients on chronic hemodialysis.

Hepatitis C virus antibody (anti-HCV) was studied in 267 patients undergoing maintenance hemodialysis using an anti-HCV enzyme-linked immunosorbent assay. Furthermore, both hepatitis B virus core antibody (anti-HBc) and human T cell leukemia virus type 1 antibody (anti-HTLV-1) were determined in these patients to compare their prevalence rates. Seventy one patients (27%) had positive anti-HCV, 134 patients (50%) positive anti-HBc and 40 patients (15%) positive anti-HTVL-1. Among the 183 patients who had received blood transfusion, the prevalence of these antibodies was 34% for anti-HCV, 56% for anti-HBc and 17% for anti-HTLV-1, respectively. A significance between those with and without blood transfusion was recognized for anti-HCV (p < 0.001) and anti-HBc (p < 0.01). Of 56 patients who had received hemodialysis for over 15 years, the positive antibody was found in 63% for anti-HCV (p < 0.001), 73% for anti-HBc (p < 0.001) and 25% for anti-HTLV-1 (p < 0.05), which was significantly higher than that of patients receiving a less than 15 years hemodialysis. The prevalence rates of anti-HCV and anti-HTLV-1 did not increase with age, while that of anti-HBc increased. These findings suggest that blood transfusions during hemodialysis play a very important role in the infection of hepatitis C virus.

Adolescent↗
PubMed1997

Fatty liver in a case with heterozygous familial hypobetalipoproteinemia.

We herein present a case of fatty liver in a patient with heterozygous familial hypobetalipoproteinemia. A 34-yr-old male presented with abnormally elevated levels of transaminases and a fatty liver. He was asymptomatic, and the physical examination showed nothing remarkable. The serum total cholesterol, triglyceride, LDL-cholesterol, and apolipoprotein B levels all ranged from low normal to one-half normal. His other laboratory data were all in the normal range. The patient's body mass index measured was 25.7 kg/m2, and he did not demonstrate obesity. He had no history of alcohol consumption. It was thus thought that the fatty liver in this case might be associated with heterozygous hypobetalipoproteinemia. Heterozygous hypobetalipoproteinemia with a bright liver by ultrasound was also found in several of the patient's family members. Based on these rare findings, heterozygous hypobetalipoproteinemia should thus be considered as a possible cause in patients presenting with an unexplained fatty liver.

Adult↗
PubMed1997

[Partial splenic embolization for the treatment of liver cirrhosis with hypersplenism: assessment of clinical response and liver function].

We have evaluated the efficacy of partial splenic embolization (SE) in the treatment in 10 cirrhotic patients with marked hypersplenism. The mean infarction rate of the spleen was 84%. The change of spleen size, peripheral blood cell counts and liver function tests after SE were investigated during 3 years, and also 10 cirrhotic patients without SE were followed as control. The residual spleens after SE did not enlarged except 1 case with 65% infarction rate of the spleen. In these cases, the SE led not only to a sustained increase in both platelet and white blood cell counts but also to a significant improvement of hepatic function tests (hepaplastin test, total cholesterol and albumin) during observation period. On the other hand, these parameters tended to decrease in control patients without SE. This study suggests that SE performed with a high infarction rate of spleen is an useful therapy for hypersplenism in cirrhosis.

Adult↗
PubMed1996

Comparison between males and females with respect to the porphyrin metabolic disorders found in workers occupationally exposed to lead.

To elucidate the sex difference in porphyrin metabolic disorders induced by lead exposure, we determined plasma delta-aminolevulinic acid (ALA), urinary ALA, and urinary coproporphyrin (CP) in 298 lead-exposed workers (160 males and 138 females), and compared the data thus obtained. The use of fluorometric high-performance liquid chromatography (HPLC) method which is highly sensitive and specific made possible the measurement of ALA in a small volume (50 microliters) of plasma. The concentrations (mean +/- SD) of lead in blood (males: 55.1 +/- 12.9 micrograms/dl; females: 54.7 +/- 13.5 micrograms/dl) indicated that the intensity of occupational exposure to lead was almost equal in the two groups. However, the elevation of plasma ALA concentration and the increased urine ALA and CP excretion among these lead workers were much higher in females than in males, confirming the finding of a sex difference in the biological effect of human exposure. The difference in urine CP excretion was especially pronounced, the mean concentration of urinary CP in the female workers being 3.5-5 times higher than that in the male workers.

Adult↗
PubMed1996

Malignant neoplasms in the Japanese community of Hisayama: mortality and changing pattern during a 30-year observation period based on a consecutive autopsy series.

To obtain a relatively true mortality from malignant neoplasms, we studied the frequency of cancers in the different sites and the changing patterns of the frequency and sites over time among residents of the community of Hisayama, where an autopsy-based population survey (autopsy rate, 80%) has been conducted since 191. During the 30-year period from 1962 to 1991, we found 438 malignant neoplasms in 407 cases among 1,250 consecutive autopsies. Stomach cancer was not frequent in type of cancer, with 123 cases (9.8%), followed by lung cancer in 62 (5.0%), colorectal cancer in 42 (3.4%), liver cancer in 37 (3.0%), and pancreatic cancer in 30 (2.4%). We compared the mortality from cancers for both autopsy and nonautopsy cases (the proportional mortality) among three 10-year periods. The proportional mortality from all cancers, as well as for lung, colorectal, and liver cancers, showed an increase in recent years, while stomach and pancreatic cancer showed a decrease. These figures were nearly similar to the mortality statistics for the Japanese population as a whole except for the observed decreasing trend in mortality from pancreatic cancer.

Adolescent↗