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K Harada

Publications and source records attributed to K Harada.

At least 343 records · Page 19Linked to original sources
PubMed1998

Prolactin-secreting macroadenoma in a prepubertal girl.

Prolactin-secreting adenoma, which usually presents with amenorrhea and galactorrhea syndrome, is quite rarely diagnosed in the prepubertal age group. We reported a rare case of a prepubertal prolactin-secreting adenoma and discuss its clinical, radiological and histological features. An 8-year-old girl presented with headache, progressive visual deterioration and precocious puberty. The serum prolactin level was 57.8 ng/ml. Computerized tomography and magnetic resonance imaging revealed an invasive suprasellar tumor. The tumor was partially resected through an interhemispheric approach in a first operation, and residual tumor was resected through the right pterional approach in a second operation. The histological diagnosis was a prolactin-secreting adenoma with high cellular pleomorphism. The Ki-67 labeling index was 5.7%, indicating aggressive biological behavior. Postoperatively, the patient was prescribed bromocriptine as maintenance therapy, and the serum prolactin level became normalized. There is a tendency for diagnosis of a prepubertal prolactin-secreting adenoma to be delayed because there are no endocrinological manifestations. Therefore, the tumor tends to become larger and invasive. Although it is rarely experienced, a prolactin-secreting adenoma should be considered in the differential diagnosis of a large, invasive parasellar lesion in the prepubertal age group.

Bromocriptine↗
PubMed1998

Characterization of a 7S globulin-deficient mutant of soybean (Glycine max (L.) Merrill).

We attempted to characterize a soybean mutant lacking the 7S globulin (beta-conglycinin) subunits, alpha, alpha' and beta. The results of Southern and northern blot analyses indicated that the deficiency is not caused by a lack of, or structural defects in, the 7S globulin subunit genes, but rather arises at the mRNA level. Despite the independent inheritance of the two loci containing the alpha-and alpha'-subunit genes and the organization of the multi-gene families encoding these subunits and the beta-subunit, a single recessive gene controls the null trait of the mutant. This, taken together with the above results, leads to the assumption that the mutant gene encodes a common factor that regulates the 7S globulin subunit genes. Transient expression of glucuronidase from the promoters of the alpha'- and beta-subunit genes was detected in the mutant cotyledons. The results of gel mobility shift assays using the 5'-flanking regions of the alpha'- and beta-subunit genes failed to detect a deficiency of nuclear factors interacting with these regions. We propose that a seed-specific mechanism of expression of 7S globulin genes might be involved in chromatin organization, and that such an organization might not work normally in the mutant. The possibility that transcript stability is lowered in the mutant is not excluded.

Antigens, Plant↗
PubMed1998

Vascular compression of the oculomotor nerve disclosed by thin-slice magnetic resonance imaging.

PURPOSE: To describe the thin-slice magnetic resonance imaging features of vascular compressive oculomotor nerve paresis. METHODS: We performed thin-slice (2 mm thick) magnetic resonance imaging of the brainstem in a 74-year-old woman with right partial oculomotor nerve paresis using spoiled gradient recalled acquisition in the steady state. RESULTS: Thin-slice magnetic resonance images disclosed that the right oculomotor nerve was compressed and dislocated superiorly and laterally by the tortuous basilar artery. No other abnormalities were observed. CONCLUSION: This is the first case report of vascular compressive oculomotor nerve paresis disclosed by thin-slice magnetic resonance imaging.

Aged↗
PubMed1998

One-stage repair of interrupted aortic arch and aortopulmonary window.

Interrupted aortic arch type A with aortopulmonary window was diagnosed in a 12-day-old neonate. A successful one-stage repair was undertaken through a midline sternotomy without circulatory arrest. The aortopulmonary window was closed through the anterior wall of communication between ascending aorta and main pulmonary artery with a patch. Position of the arterial cannula was changed during the repair, which made it possible to mobilize and expose the aortic arch for the completion of direct anastomosis.

Aorta, Thoracic↗
PubMed1998

Molecular cloning and expression of inducible nitric oxide synthase in chick embryonic ventricular myocytes.

OBJECTIVE: Inducible nitric oxide synthase (iNOS) has been implicated to contribute to myocardial dysfunction in various settings, but considerable species differences have been noted in the levels of iNOS expression and its function in several tissues. The aim of this study was to elucidate evolutional changes in myocardial iNOS expression and function. METHODS: An iNOS cDNA clone was isolated by RT-PCR from the 10-day old cultured chick embryonic ventricular myocytes stimulated with 10 micrograms/ml of lipopolysaccharide. Expression of the iNOS mRNA was analyzed with Northern blot analysis and RNase protection assay. The iNOS activity was estimated from conversion rates of L-arginine to L-citrulline and intracellular cGMP contents were measured with radioimmunoassay. Furthermore, both [Ca2+]i (fluorescent dye indo-1) and cell contraction (video motion detector) were simultaneously recorded. RESULTS: Aside from the primer sequences, the insert (1026 bp) of the cDNA clone showed 66.4% identity at the deduced amino acid level to the human iNOS cDNAs. Northern blot analysis revealed that chicken iNOS mRNA of approximately 4.5 kb was induced by lipopolysaccharide within 6 h in the cultured myocytes. RNase protection assay also showed that lipopolysaccharide provoked 14.6 +/- 5.1-fold increases (n = 6, p < 0.05) in the iNOS mRNA signals within 6 h. The iNOS activity (+300%, P < 0.05) as well as the intracellular cGMP contents (+75%, P < 0.01) were significantly augmented in the lipopolysaccharide-stimulated cells. Both the cell contraction and [Ca2+]i were significantly reduced after the administration of a large amount (10 mM) of L-arginine in the myocytes pretreated with both lipopolysaccharide and NG-monomethyl-L-arginine (100 microM). CONCLUSION: As like as the nucleotide and amino acid sequences, the myocardial effects of the iNOS may also be evolutionary conserved.

Amino Acid Sequence↗
PubMed1998

Immunohistochemical studies on phosphorylation of tyrosine hydroxylase in central catecholamine neurons using site- and phosphorylation state-specific antibodies.

Antibodies raised to phosphorylated forms of tyrosine hydroxylase, the first and rate-limiting enzyme in the catecholamine biosynthesis, were applied in immunohistochemical studies on rat brain slices incubated in vitro with a phosphodiesterase inhibitor (3-isobutyl-1-methylxanthine, IBMX) and on forskolin on formalin-perfused rat brains. Four antisera/antibodies were used: polyclonal rabbit antisera to (i) tyrosine hydroxylase phosphorylated at serine 40 (THS40p antiserum), (ii) tyrosine hydroxylase phosphorylated at serine 19 (THS19p antiserum), (iii) the native enzyme (pan-tyrosine hydroxylase antiserum), and mouse monoclonal antibody to (iv) native tyrosine hydroxylase. In the in vitro studies THS40p-like immunoreactivity was not observed unless slices were treated with IBMX-forskolin after which a dense fibre network was found in the striatum, and immunoreactive cell bodies were found in the ventral mesencephalon, especially in the ventral tegmental area. Although these cells were pan-tyrosine hydroxylase-positive, several of them were not stained with the tyrosine hydroxylase-monoclonal antibody. Moreover, there was a marked reduction of tyrosine hydroxylase-monoclonal antibody-immunoreactive fibres in drug-treated slices, suggesting that this tyrosine hydroxylase-monoclonal antibody does not recognize the serine 40-phosphorylated form of tyrosine hydroxylase. Treated slices did not show any THS40p-immunoreactive cell bodies in the dopaminergic A11 cell group and only a few, weakly fluorescent neurons were observed in locus coeruleus. However, a sparse fibre plexus was observed in locus coeruleus, possibly reflecting epinephrine fibres. In the perfused brains THS40p-like immunoreactivity could be visualized in some dopamine neurons in the ventral mesencephalon, especially the A10 area, and in noradrenergic locus coeruleus neurons, whereas THS19p-like immunoreactivity was found in all catecholamine groups studied, similar to the results obtained with the pan-tyrosine hydroxylase antiserum and the tyrosine hydroxylase-monoclonal antibody. In forebrain areas known to be innervated by mesencephalic dopamine neurons, no THS40p-positive fibres were observed, whereas THS19p-immunoreactive fibres were found in subregions of the striatum, olfactory tubercle and nucleus accumbens, essentially overlapping with dopamine fibres previously shown to contain cholecystokinin-like immunoreactivity. The present results suggests that antibodies directed against phosphorylated forms of tyrosine hydroxylase can be used to evaluate the state of tyrosine hydroxylase phosphorylation in individual neuronal cell bodies and processes both in vitro and in vivo.

1-Methyl-3-isobutylxanthine↗
PubMed1998

Morphological maturation of left ventricle in fetal rats: changes in left ventricular volume, mass, wall thickness, and mitral valvular size.

Morphological changes in the left ventricles of fetal rats from 17 to 21 days of gestation were studied using the rapid whole-body freezing technique. Wistar rats (pregnant period, 21.5 days) were used. Left ventricular volume, mass, wall thickness, and area of mitral valvular orifice increased rapidly and linearly during the observation period. The ratio of the mass to volume of the left ventricle gradually decreased as the fetuses grew older, and by 21st day of gestation it was 52% that of 17 days of gestation. The ratio of the area of mitral valvular orifice to left ventricular volume also decreased by 29% during the same period. Thus we see that the left ventricle of fetal rat was in the condition of physiological hypertrophy and had the large mitral valvular orifice in early gestational age. We suggest that the decrease of the ratio of mass to volume of the left ventricle with the progression of gestational age indicates the morphological maturation of the left ventricle to adapt to the rapid increase of volume overload during the perinatal period.

Animals↗
PubMed1998

Synthesis and evaluation of hydroxamamide-based tetradentate ligands as a new class of thiol-free chelating molecules for 99mTc radiopharmaceuticals.

Both N,N'-ethylene bis(benzohydroxamamide) [(C2(BHam)2)] and N,N'-propylene bis(benzohydroxamamide) [(C3(BHam)2)] were designed as new thiol-free chelating molecules for 99mTc radiopharmaceuticals. Synthetic procedures using oxadiazoline intermediates were developed for C2(BHam)2 and C3(BHam)2. Both C2(BHam)2 and C3(BHam)2 formed 99mTc complexes with high yields over a wide pH range (pH 3-12) at room temperature. Complexation yields of over 95% were achieved at ligand concentrations as low as 2.5 x 10(-6) M. Reversed-phase HPLC analyses indicated that both C2(BHam)2 and C3(BHam)2 formed 99mTc complexes as single species with stabilities much higher than those of 99mTc-BHam. Selective complex formation of 99mTc with the two ligands was observed in the presence of human IgG. No decomposition with low protein binding were demonstrated when the two 99mTc complexes were incubated in murine plasma. Although further structural studies are required, these findings implied that the Ham-based tetradentate ligands would serve as new chelating molecules for 99mTc radiopharmaceuticals.

Animals↗
PubMed1998

Changes in patterns of left ventricular diastolic filling revealed by Doppler echocardiography in infants with ventricular septal defect.

To evaluate left ventricular diastolic filling in infants with ventricular septal defect, which has yet to be documented, we measured various Doppler echocardiographic indexes from transmitral flow in the following groups: 10 infants with ventricular septal defect without pulmonary hypertension; 10 infants with ventricular septal defect with pulmonary hypertension; and 9 normal infants to serve as controls. The peak A, total velocity time integral, E area, and A area in patients without pulmonary hypertension were all significantly larger than those in controls. The peak ratio E/A, and 1/3 filling fraction, in patients without pulmonary hypertension were significantly lower than in controls. The peak A, A area, and deceleration time in patients with pulmonary hypertension were significantly larger than in patients without pulmonary hypertension and controls. The peak E/A, area E/A, and 1/3 filling fraction in patients with pulmonary hypertension were significantly lower than in those without pulmonary hypertension and controls. The index of left ventricular mass, as well as the index of end-diastolic left ventricular wall thickness, correlated strongly with peak A, A area, and deceleration time. The ratio between the systolic pulmonary and systemic pressures correlated strongly with peak A, A area, peak E/A, area E/A, and 1/3 filling fraction. These results demonstrated that the patterns of left ventricular filling in infants with ventricular septal defect were different from those in normal infants, and suggested that the abnormal patterns may indicate the insufficiency of adaptation of left ventricle (increase of left ventricular compliance) for volume overload in the presence of a ventricular septal defect.

Cardiac Catheterization↗
PubMed1998

Transformation of rat glioma cells with the M-CSF gene inhibits tumorigenesis in vivo.

Macrophage colony-stimulating factor (M-CSF) is a potent stimulator of the effector cells such as monocytes and macrophages. To evaluate the effect of M-CSF on malignant gliomas, we transfected the rat gliosarcoma cell line (9L) with human M-CSF expression vector (pCEF-MCSF) by a liposome method. Transfectants were selected using G418-containing medium. As a control, 9L cells transfected with pRc/CMV and selected by G418 were used. The effects of M-CSF gene transfection on tumor cell proliferation in vitro and in vivo were examined. All growth rate did not change in vitro. While the control 9L cells formed progressively enlarging masses, 9L cells transfected with the M-CSF gene did not develop into tumors after the injection into rats. On the other hand, in rats receiving anti-asialo GM1 antibody, 9L cells transfected with M-CSF gene developed into tumors, though at a slower rate than control 9L cells. Histologic examination after transplantation of 9L cells transfected with M-CSF gene disclosed intense infiltration of macrophages in the tumor. Thus M-CSF gene transfection into glioma cells stimulates an antitumor effect.

Animals↗
PubMed1998

Analysis of human T-cell antigen receptor variable beta gene usage following vaccination with recombinant HBsAg.

We analyzed the TcR Vbeta gene usage before and after vaccination with the hepatitis B vaccine since changes in the TcR Vbeta gene families would be considered to provide preliminary evidence of a mechanism to prevent HBV infection. Six healthy adult volunteers received immunizations. TcR Vbeta usage, T-cell proliferation, and HLA class II alleles were examined in peripheral blood mononuclear cells (PBMC) both before and after vaccination. Furthermore, TcR Vbeta usage in postimmunization PBMC was also compared with PBMC cultured with recombinant HBsAg (rHBsAg). The level of in vitro T-cell proliferation in the presence of rHBsAg increased significantly (P < 0.01) in PBMC isolated after vaccinations. Increases in the different TcR Vbeta genes were also observed in each individual following vaccinations, regardless of the similarity in their HLA alleles. Specific HBV-related antigen-responsive T cells were induced after HB vaccination, without any common restriction for the TcR Vbeta gene families. The mechanism that helps prevent HBV infection was thus found to involve multiclonal alterations in the TcR Vbeta repertoire.

Adult↗
PubMed1998

Relationship between interleukin-6 and proliferation and differentiation in cholangiocarcinoma.

AIMS: Interleukin-6 (IL-6) has been implicated as a mediator of growth control in several human neoplasms. The significance of IL-6 expression in human cholangiocarcinoma was examined in this study. METHODS AND RESULTS: IL-6 expression was examined in 43 surgically resected cholangiocarcinomas and a cholangiocarcinoma cell line CCKS1, derived from abdominal metastasis of moderately differentiated adenocarcinoma, by immunohistochemical and in-situ hybridization techniques. In non-neoplastic bile ducts, IL-6 was constitutively but weakly expressed. In surgical cases of cholangiocarcinoma, IL-6 was frequently and strongly expressed in the cytoplasm of well-differentiated cholangiocarcinoma, while its expression was decreased, and less intense or absent in moderately and poorly differentiated areas, respectively. IL-6 mRNA was detected in the cytoplasm of carcinoma cells of two cases of cholangiocarcinomas positive for IL-6. IL-6 was detected in hepatic bile from two cholangiocarcinoma cases studied. The proliferation antigen Ki67 was found to be more frequently expressed in IL-6 negative carcinoma cells than in IL-6 positive carcinoma cells (P < 0.01). In cultured carcinoma cells line CCKS1, IL-6, IL-6 mRNA and IL-6 receptor alpha chain were detected in the cytoplasm of carcinoma cells, suggesting an autocrine effect of IL-6 on carcinoma cells. CONCLUSION: IL-6 expression is inversely related to cell proliferation and positively related to differentiation in cholangiocarcinoma.

Aged↗
PubMed1998

Epithelioid cell granulomas in chronic hepatitis C: immunohistochemical character and histological marker of favourable response to interferon-alpha therapy.

AIMS: The clinicopathological significance of intrahepatic epithelioid cell granulomas in chronic hepatitis C was determined. METHOD AND RESULTS: Granulomatous lesions were surveyed in 542 liver biopsy specimens and were immunohistochemically examined. We also tested whether this lesion is a marker of response to interferon-alpha therapy in chronic hepatitis C. Granulomatous lesions in hepatic lobules and/or portal tracts were identified in 11/542 (2%) cases with chronic hepatitis C. Granulomas were positive for HLA-DR and beta 2-microglobulin, and were surrounded by T-cells. Among them, three chronic hepatitis C cases showed portal granulomas with mild biliary epithelial damage. Bile ducts showing mild epithelial damage in chronic hepatitis C were positive for beta 2-microglobulin, but negative for HLA-DR, while both antigens were frequently expressed in damaged bile ducts in primary biliary cirrhosis (PBC). All five cases of chronic hepatitis C with granulomas who had interferon-alpha therapy and were followed up and were found to have responded well. CONCLUSION: Granulomas showed the same immunohistochemical phenotypes, though the expression of HLA-DR on bile ducts in PBC but not in chronic hepatitis C suggests a different pathogenesis. Granulomas may predict a favourable response to interferon-alpha therapy in chronic hepatitis C.

Adult↗
PubMed1998

Postischemic reperfusion induces alpha-fodrin proteolysis by m-calpain in the synaptosome and nucleus in rat brain.

A membrane cytoskeletal protein, fodrin, is a substrate for a Ca2+-dependent protease, calpain. It remains unknown whether mu-calpain or m-calpain is involved in the proteolysis of either alpha- or beta-fodrin and in what subcellular localization during ischemia and reperfusion of the brain. To address these issues, we examined the distribution of fodrin and calpain and the activities of calpain and calpastatin (endogenous calpain inhibitor) in the same subcellular fractions. Rat forebrain was subjected to ischemia by a combination of occlusion of both carotid arteries and systemic hypotension, whereas reperfusion was induced by releasing the occlusion. Immunoblotting, activity measurement, and casein zymography did not detect the presence of mu-calpain or a significant change of m-calpain level after ischemia or reperfusion. However, casein zymography revealed a unique Ca2+-dependent protease that was eluted with both 0.18 and 0.40 M NaCl from a DEAE-cellulose column. Alpha- and beta-fodrins and m-calpain were found to be rich in the synaptosomal, nuclear, and cytosolic subfractions by immunoblotting analysis. Reperfusion (60 min) following ischemia (30 min) induced selective proteolysis of alpha-fodrin, which was inhibited by a calpain inhibitor, acetylleucylleucylnorleucinal (400 microM, 1 ml, i.v.). The mu-calpain-specific fragment of beta-fodrin was not generated during ischemia-reperfusion, supporting the possibility of the involvement of m-calpain rather than mu-calpain in the alpha-fodrin proteolysis.

Animals↗
PubMed1998

Role of serine-19 phosphorylation in regulating tyrosine hydroxylase studied with site- and phosphospecific antibodies and site-directed mutagenesis.

The effects of depolarization by elevated potassium concentrations were studied in PC12 cells and in stably transfected AtT-20 cells expressing wild-type or [Leu19]-recombinant tyrosine hydroxylase (rTH). Changes in the phosphorylation states of Ser19 and Ser40 in tyrosine hydroxylase (TH) were determined immunochemically using antibodies specific for the phosphorylated state of each site and compared with changes in TH activity in PC12 cell lysates and with changes in L-DOPA biosynthesis rates in intact AtT-20 cells. Treatment of either PC12 cells or AtT-20 cells expressing wild-type rTH with elevated potassium produced a transient increase in the phosphorylation state of Ser19 (up to 0.7 mol of phosphate/mol of subunit) in concert with a more gradual and sustained increase in Ser40 phosphorylation. Elevated potassium treatment also increased TH activity in PC12 cell lysates, but these increases paralleled the temporal course of Ser40, as opposed to Ser19, phosphorylation. Similarly, increases in DOPA accumulation produced by elevated potassium in AtT-20 cells expressing wild-type rTH paralleled the increases in the phosphorylation state of Ser40 but not Ser19. Moreover, elevated potassium produced comparable increases in DOPA accumulation in AtT-20 cells expressing rTH in which Ser19 phosphorylation had been eliminated (by substitution of Leu for Ser19). Thus, depolarization-induced increases in the stoichiometry of Ser19 phosphorylation do not appear to influence directly the activity of TH in situ.

Amino Acid Substitution↗
PubMed1998

Relationship of apolipoprotein E phenotypes to serum lipid and lipoprotein levels in Japanese schoolchildren.

The distribution of apolipoprotein (apo) E phenotypes was investigated in Japanese schoolchildren and an attempt was made to determine whether the apoE phenotypes influence the serum levels of lipid and lipoprotein. The subjects were 289 children from a junior high school (145 M, 144 F, aged 12-13 y). The E3/3 phenotype was demonstrated in 69.9%, E4/3 in 18.7%, E2/3 in 9.0%, E4/2 in 1.4%, E4/4 in 0.7% and E5/4 in 0.3%. E2/2 was not detected. Serum levels of total cholesterol and low-density lipoprotein-cholesterol were progressively lower in the phenotypes E4/3, E3/3 and E2/3. The serum level of high-density lipoprotein-cholesterol showed a progressive increase in the same order. In conclusion, Japanese schoolchildren with E4/3 already had an atherogenic serum lipid profile.

Adolescent↗
PubMed1998

Evidence for linkage of human primary systemic carnitine deficiency with D5S436: a novel gene locus on chromosome 5q.

Primary systemic carnitine deficiency (SCD) is a rare hereditary disorder transmitted by an autosomal recessive mode of inheritance. The disorder includes cardiomyopathy, muscle weakness, hypoketotic coma with hypoglycemia, and hyperammonemia. In this study, we conducted a linkage analysis of a Japanese SCD family with a proband-a 9-year-old girl-and 26 members. The serum and urinary carnitine levels were determined for all members. The entire genome was searched for linkage to the gene locus for SCD, by use of a total of approximately 300 polymorphic markers located approximately 15-20 cM apart. In the family, there were two significantly different phenotypes, in terms of serum free-carnitine levels: low serum free-carnitine level (29.5+/-5.0 microM; n=14) and normal serum free-carnitine level (46.8+/-6.2 microM; n=12). There was no correlation of urinary free-carnitine levels with the low serum-level phenotype (putative heterozygote), but in normal phenotypes (wild type) urinary levels decreased as the serum levels decreased; renal resorption of free carnitine appeared to be complete in wild-type individuals, when the serum free-carnitine level was <36 microM. Linkage analysis using an autosomal dominant mode of inheritance of heterozygosity revealed a tight linkage between the disease allele and D5S436 on chromosome 5q, with a two-point LOD score of 4.98 and a multipoint LOD score of 5.52. The haplotype analysis revealed that the responsible genetic locus lies between D5S658 and D5S434, which we named the "SCD" locus. This region was syntenic with the jvs locus, which is responsible for murine SCD. Phylogenic conversion of the SCD locus strongly suggests involvement of a single gene, in human SCD.

Carnitine↗