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Biomedical subjects

N Harada

Publications and source records attributed to N Harada.

At least 289 records · Page 16Linked to original sources

Endosonography-guided celiac plexus neurolysis.

Endosonography-guided celiac plexus neurolysis is a new technique that permits chemical splanchnicectomy in patients with abdominal pain due to malignancy. The procedure can be performed on an outpatient basis in individuals undergoing endosonographic examinations for staging and biopsy purposes.

Abdominal Neoplasms↗

[Induction chemotherapy based on histoculture drug response assay for a patient with advanced thymic cancer--a case report].

Histoculture drug response assay (HDRA) was applied to a biopsy specimen of advanced thymic cancer from a 68 years-old male patient. HDRA revealed that the tumor was not sensitive to CDDP but highly sensitive to 5-FU, ADM and MMC, which were administered as induction chemotherapy. The tumor regressed to 14% of the pretreatment size and was able to be completely resected with right and left brachiocephalic veins, superior vena cava, pericardium, right phrenic nerve and a part of right lung. Histologically, only a few small cancer nests remained in the fibrous tissue. The patient is alive and disease free 32 months after surgery. This result suggests that HDRA is useful to select anticancer agents which are sensitive to a rare kind of carcinoma such as thymic cancer.

Antineoplastic Combined Chemotherapy Protocols↗

[Diagnosis of tumor extension of ductal adenocarcinoma of the pancreas based on histological findings].

This study was undertaken to evaluate the diagnosis for tumor extension of ductal adenocarcinoma of the head of the pancreas based on histological investigation. From 1968 to 1995, 316 patients underwent radical resection and histological tumor extension was quite as follows; the rate of invasion to the anterior pancreatic capsule was 49%, invasion to the retroperitoneal tissue was 77%, invasion to the portal vein system was 38%, invasion to the extrapancreatic nerve plexus was 53% and lymph node metastases were 79%. 249 patients was performed extended radical operation consisted of regional lymphadenectomy, retroperitoneal dissection and resection of portal vein system, however non-curative resection was 52% with tumor invasion to dissected pancreatic surface in 88% of non-curative patients. And there was no 5-year survivor with non-curative resection. The extended radical operation should be indicated for patients who will have curative resection. Then, we set up clinical stage (CS; CSI approximately IV) by three factors related to resectability mostly; invasion to retroperitoneal tissue (RP), invasion to portal vein system (PV), invasion to major arterial system (A). It was also set up preoperative diagnostic criteria for RP, PV and A factor by computed tomography (CT) or abdominal angiography. From 1989 to 1995, 101 patients who had extended radical operation were investigated prospectively. The rate of accuracy of preoperative diagnosis of tumor extension were about 80% in each factor. Curability was 94% in CS I, 67% in CS II, 43% in CS III, respectively, and 3-year survival rate was 53% in CS I, 35% in CS II, 2-year survival rate was 8% in CS III. However, in CS IV the rate of non-curative resection was 77% and there was no 2-year survivor. It was concluded that extended radical operation of ductal adenocarcinoma of the head of the pancreas should be indicated for patients in less than CS III diagnosed by CT or angiography preoperatively.

Carcinoma, Ductal, Breast↗

Effect of histamine on intracellular Ca2+ concentration in guinea pig isolated vestibular hair cells.

The present study examined the effects of histamine in the guinea pig isolated vestibular hair cells (VHCs) by measuring the dynamic changes of intracellular free calcium ion ([Ca2+]i) concentration using calcium sensitive dye Fura-2. The histamine-induced calcium response in VHCs was markedly increased at the concentration of 10 microM histamine in the presence of extracellular Ca2+, while in the absence of extracellular Ca2+, a slow increase of [Ca2+]i was evident. Receptor specificity of the response to histamine was examined: promethazine (H1 receptor antagonist), cimetidine (H2 receptor antagonist) and thioperamide (H3 receptor antagonist) completely blocked the histamine-induced calcium response at the concentrations of 2.5 microM, 1.0 microM and 1.0 nM, respectively. The responses were mediated by H1, H2 and H3 receptors and resulted in a rise of [Ca2+]i due to an influx of Ca2+ from the extracellular space and a release from intracellular stores. Our preliminary data suggest that under immuno-pathological conditions of the inner ear, histamine released from the mast cells distributed in the endolymphatic sac may act through receptors located on the vestibular hair cell membrane and may regulate the cell function and the signal transduction in the vestibular nerve-hair cell afferent system.

Afferent Pathways↗

[Plasma cell interstitial pneumonia as a manifestation of multicentric Castleman's disease].

A 12-year-old boy was admitted to our hospital because of abnormal shadows on a chest radiograph, slight fever, and superficial lymphadenopathy. Laboratory examination showed anemia (Hb 9.9 g/dl) and hyperimmunoglobulinemia (IgG 5469 mg/dl) without M protein. A chest CT scan showed bilateral diffuse shadows and bilateral hilar lymphadenopathy. Biopsy specimens of an inguinal lymph node and a lung showed many lymphoid follicles with germinal centers, and marked infiltration of mature plasma cells in the interfollicular area without destruction of follicular structures. The polyclonality of the plasma cells was confirmed by immunohistochemistry. The patient was not treated because these results excluded malignant disease and he was asymptomatic. At the age of 17 years, he was admitted to our hospital again because of dyspnea and a tendency to bleed. Interstitial pneumonia, hyperimmunoglobulinemia (IgG 13900 mg/dl), and anemia (Hb 6.6 g/dl) were found, along with thrombocytopenia (2.5 x 10(4)/mm3) and proteinuria. The serum interleukin-6 level was high: 177 pg/ml. Bronchoalveolar lavage fluid contained many plasma cells. Therapy with corticosteroids and immunosuppressant medication was effective. Our diagnosis was plasma cell interstitial pneumonia as a manifestation of multicentric Castleman's disease.

Adolescent↗

Aberrant expression of aromatase in breast cancer tissues.

The expression of aromatase is tissue-specifically regulated through the alternative use of multiple exons 1 and promoters. We analysed expression levels of aromatase mRNA, preferential utilization of multiple exon 1 of the human aromatase gene, and transcriptional regulation of their multiple promoters in breast cancer tissues by newly developed fluorometric methods. The expression levels of aromatase mRNA in breast cancer tissues were significantly higher than those in regions distal to tumours or in non-malignant breast tissues. Aromatase mRNA in these non-malignant tissues was transcribed from skin fibroblast/fetal liver-specific exon 1 (exon 1b) of the aromatase gene. However, in half the cases of breast cancer patients, the utilization of multiple exons 1 in the aromatase mRNA changed from exon 1b to ovary-specific exon 1 (exon 1c) in their breast tissues. Aromatase mRNA in HepG2 cells as well as in non-malignant breast tissues was also transcribed from exon 1b. Then, the promoter region responsible for the exon 1b-specific utilization in HepG2 cells was examined by fluorometric promoter assay using a new reporter containing four major alternative exons 1 and promoters. The results suggested that transcriptional elements determining preferential utilization of exon 1b in the cells was located on the promoter region of exon 1b from -255 to -1145. To investigate further the cause of the elevation of aromatase mRNA and the switching from exon 1b to exon 1c in the transcription of the aromatase gene, the effects of various factors on the expression levels and preference of alternative exons 1 were examined in cultured adipose stromal cells from breast tissues. Aromatase mRNA was transcribed from exon 1b in the stromal cells, cultured in the presence of calf serum. However, removal of the serum or the addition of forskolin or phorbol ester (TPA) induced a rapid elevation of aromatase mRNA and the switching of aromatase transcripts to exon 1c in the cells, whereas TGFbeta almost abolished the expression of aromatase mRNA. Because co-culture of cancer cells such as MCF-7 increased aromatase mRNA of the cells cultured in the serum-containing medium, it is possible that cancer cells secret stimulatory factors acting like forskolin or TPA, or consume serum inhibitory factors acting like TGFbeta, consequently causing levels of aromatase mRNA to increase.

Adult↗

Autonomous expression of aromatase during development of mouse brain is modulated by neurotransmitters.

A transient increase in aromatase activity is known to occur in the hypothalamus of rodents in pre- and postnatal periods. The mechanisms regulating such a developmental increase of brain aromatase was studied in fetal mouse diencephalic cells, by measuring aromatase mRNA levels by a quantitative reverse transcription-polymerase chain reaction (RT-PCR) method. When slices of diencephalon were cultured on embryonic day (E) 12, E13 and E15, the level of aromatase mRNA continued to increase for the first 2 to 3 days. A time-dependent increase of mRNA was also shown for 3 days in E13 neuronal cells dissociated with papain and cultured in chemically defined medium. However, no significant increase was observed in E10 or E11 brain cells cultured by either method. Aromatase mRNA was detected in neither cerebral cortex neurons nor astrocytes. An alpha1-selective adrenergic agonist, phenylephrine, increased aromatase in the E13 diencephalic neurons in culture, whereas prazosin, an alpha1-antagonist, suppressed the mRNA level. Ligands for alpha2- or beta-adrenergic receptors did not alter the mRNA level. Substance P, cholecystokinin, neurotensin, and brain natriuretic peptide as well as phorbol 12-myristate 13-acetate and dibutyryl-cyclic GMP all increased the mRNA level. We concluded that: (a) the developmental increase of aromatase mRNA in diencephalic neurons is an autonomous event and is perhaps genetically regulated after E12; (b) aromatase mRNA is expressed in a cell type- and region-specific manner; and (c) protein kinases C and G activated via receptors of the specific neurotransmitters may be involved in modulation of the developmental expression of aromatase mRNA.

Animals↗

[A surgical case for the huge chronic expanding hematoma developed in the thoracic cavity].

We report a case of operation against chronic expanding hematoma developed in the pleural cavity of the patient who were treated as anaplastic anemia. 69-year-old man had been underwent thymectomy because of the thymoma and hemogenic pleural effusion 8 years ago. Then, last year, he was pointed out severe thrombocytopenia and underwent transfusion of thrombocyte. In the same period, chest X-ray examination revealed development of the tumor-like shadow in the left lung field. The abnormal shadow has enlarged, so the patient admitted us. X-ray findings revealed the huge tumor occupied completely the left pleural space. He was also pointed out severe pancytopenia (WBC: 2,600/mm3, RBC: 172 x 10(4)/mm3, thrombocyto: 1.9 x 10(4)/mm#), and the examination of bone marrow revealed anaplastic anemia. Thoracotomy was underwent, and the tumor was resected. Pathological diagnosis of the tumor was huge hematoma. Negative pressure in the pleural space would keep the hemorrhage and make hematoma huge. The hematoma in the pleural space should be resected as soon as the diagnosis is decided.

Aged↗

Prevalence of hepatitis B surface antigen (HBsAg) in Viqarunnessa noon girls' school children in Dhaka, Bangladesh.

Screening of serum samples from 836 apparently healthy school girls with sound socioeconomical background from Viqarunnessa Noon Girls' School in Dhaka, was done for hepatitis B surface antigen (HBsAg) by Latex quick test and all Latex quick test positive samples were rechecked by enzyme-linked immunosorbent assay. Thus the prevalence of HBsAg among healthy female school age children was 2.3% by the former method and 0.8% by the latter. Hepatitis B virus (HBV) infection is more common in Bangladesh but HBsAg prevalence rate in normal school age children of the present study was much lower than reported from many other parts of the world. The reason of this fact presumably was that in this study serum specimens were collected from apparently healthy female children belonging to high socioeconomic status in Bangladesh. Further studies are appreciated to determine the prevalence of HBsAg among healthy low socioeconomic school age children and to investigate HBsAg subtypes and possible main mode of transmission of HBV in Bangladeshi population.

Adolescent↗

Theoretical calculation of circular dichroic exciton-split spectra in presence of three interacting 2-naphthoate chromophores.

Ample experimental evidence shows that the principle of pairwise additivity holds in exciton coupled CD systems consisting of three or more interacting chromophores. This principle is one of the most important from a practical viewpoint. However, the rule has so far not been proven theoretically. In order to prove the additivity principle by calculation, three ouabagenin bisnaphthoates and 1,3,19-tris-naphthoates were chosen as models. Since this represents a challenging case where the 2-naphthoate chromophore can adopt s-cis or s-trans conformations and, moreover the C-19 side chain of ouabagenin is flexible, Monte Carlo conformational search was performed prior to the CD calculation. The pi-electron SCF-CI-DV MO calculation of CD was applied to all conformers within 3 kcal/mol range from the lowest energy. Good agreement between experimental and theoretical CD spectra was obtained for the ouabagenin bisnaphthoates and trisnaphthoate.

Carboxylic Acids↗

Interleukin-4 activates two distinct pathways of phosphatidylinositol-3 kinase in the same cells.

We have recently demonstrated that c-fes protooncogene product (FES), or a FES-related protein, associates with the interleukin-4 receptor alpha chain (IL-4R alpha) and phosphatidylinositol-3 (PI3) kinase in mouse T cell lines; however, others have demonstrated that PI3 kinase associates with IL-4R alpha through tyrosine phosphorylated insulin receptor substrate (IRS)-2 in other cell types. In order to examine whether IL-4 activates these two distinct PI3 kinase pathways in the same cells, we analyzed association of PI3 kinase with IRS-2, and tyrosine phosphorylation of IRS-2, in a mouse pro-B cell line, Ba/F3, and a mouse mast cell line, MC9. In both cell lines, IL-4 induced tyrosine phosphorylation of IRS-2, association of PI3 kinase with IRS-2, and FES or a FES-related protein. These results indicate that IL-4 activates two distinct PI3 kinase pathways in the same cells. We further identified the critical region in the cytoplasmic domain of IL-4R alpha required for tyrosine phosphorylation of IRS-2.

Animals↗

Interleukin-4 induces association of the c-fes proto-oncogene product with phosphatidylinositol-3 kinase.

We have previously demonstrated that interleukin-4 (IL-4) induces tyrosine phosphorylation of a protein closely related or identical to the c-fes proto-oncogene product (FES) and association of this protein with the IL-4 receptor alpha chain (IL-4R alpha). IL-4 is known to induce association of phosphatidylinositol-3 (PI3) kinase with the IL-4R alpha. Since FES contains the consensus motifs for PI3 kinase binding, we tested the possibility that FES may associate with PI3 kinase upon IL-4 stimulation. We demonstrate herein that IL-4 stimulation induced rapid association of FES or a related protein with PI3 kinase in mouse T-cell lines. We also show an association of human FES (hFES) with the src homology 2 (SH2) domain of PI3 kinase in a COS7 cell expression system. The in vitro PI3 kinase assay using COS7 cells suggested that hFES partly contributes to the association between the hIL-4R alpha and PI3 kinase. We have further identified the important region in the cytoplasmic domain of the hIL-4R alpha for association of tyrosine-phosphorylated hFES with the hIL-4R alpha and SH2 domain of PI3 kinase using a COS7 cell expression system. These results suggest that FES or a related protein/PI3 kinase pathway may play a role in the pleiotropic effects of IL-4.

Animals↗

Diagnosis of four chromosome abnormalities of unknown origin by chromosome microdissection and subsequent reverse and forward painting.

A molecular cytogenetic method consisting of chromosome microdissection and subsequent reverse/forward chromosome painting is a powerful tool to identify chromosome abnormalities of unknown origin. We present 4 cases of chromosome structural abnormalities whose origins were ascertained by this method. In one MCA/MR patient with an add(5q)chromosome, fluorescence in situ hybridization (FISH), using probes generated from a microdissected additional segment of the add(5q) chromosome and then from a distal region of normal chromosome 5, confirmed that the patient had a tandem duplication for a 5q35-qter segment. Similarly, we ascertained that an additional segment of an add(3p) chromosome in another MCA/MR patient had been derived from a 7q32-qter segment. In a woman with a history of successive spontaneous abortions and with a minute marker chromosome, painting using microdissected probes from the whole marker chromosome revealed that it was i(15)(p10) or psu dic(15;15)(q11;q11). Likewise, a marker observed in a fetus was a ring chromosome derived from the paracentromeric region of chromosome 19. We emphasize the value of the microdissection-based chromosome painting method in the identification of unknown chromosomes, especially for marker chromosomes. The method may contribute to a collection of data among patients with similar or identical chromosome abnormalities, which may lead to a better clinical syndrome delineation.

Abnormalities, Multiple↗

Interleukin 4 (IL-4) blocks the IL-2-induced increased in natural killer activity and DNA synthesis of decidual CD16-CD56bright NK cells by inhibiting expression of the IL-2 receptor alpha, beta, and gamma.

The natural killer (NK) activity and DNA synthesis of decidual CD16-CD56bright NK cells were markedly elevated by treatment with interleukin 2 (IL-2). IL-4 did not affect NK activity or DNA synthesis of decidual CD16-CD56bright NK cells, but inhibited the IL-2-induced NK activity and DNA synthesis in a dose-dependent manner. Flow cytometry of decidual mononuclear cells cultured in IL-2 or IL-4 or both IL-2 and IL-4 demonstrated IL-4 inhibition of the expression of the IL-2 receptor alpha (IL-2R alpha), IL-2R beta, and IL-2R gamma on decidual CD16-CD56bright NK cells. This suggests that IL-4 blocks the IL-2-induced NK activity and DNA synthesis of decidual CD16-CD56bright NK cells by inhibiting the expression of IL-2R alpha, IL-2R beta, and IL-2R gamma.

CD56 Antigen↗

The alternative exons 1 of the mouse aromatase cytochrome P-450 gene.

Aromatase cDNA clones were isolated from cDNA libraries of mouse hypothalamus, amygdala and ovary. Analysis of the nucleotide sequences of the 5' regions of the obtained cDNAs suggested that the mouse aromatase gene is tissue-specifically regulated by alternative exons 1. There were obvious differences between the 5' regions of the brain and ovary aromatase cDNAs, but no difference was found between the sequences of the hypothalamus and amygdala ones. We further isolated a mouse genomic DNA clone containing brain- and ovary-specific exons 1. The brain specific exons 1 and their promoters were highly homologous in the human and mouse aromatase genes. In contrast there were several differences in the sequences among the promoter regions of the ovary-specific exons 1 of the mouse, human and rat aromatase genes, significant homology between their sequences was also observed. The present results demonstrate that expression of the mouse aromatase gene is also tissue-specifically regulated through the use of alternative exons 1 and promoters, as reported for man.

Alternative Splicing↗

Identification of AF-6 and canoe as putative targets for Ras.

Ras (Ha-Ras, Ki-Ras, N-Ras) is implicated in the regulation of various cell functions such as gene expression and cell proliferation downstream from specific extracellular signals. Here, we partially purified a Ras-interacting protein with molecular mass of about 180 kDa (p180) from bovine brain membrane extract by glutathione S-transferase (GST)-Ha-Ras affinity column chromatography. This protein bound to the GTP gamma S (guanosine 5'-(3-O-thio)triphosphate, a nonhydrolyzable GTP analog).GST-Ha-Ras affinity column but not to those containing GDP.GST-Ha-Ras or GTP gamma S.GST-Ha-Ras with a mutation in the effector domain (Ha-RasA38). The amino acid sequences of the peptides derived from p180 were almost identical to those of human AF-6 that is identified as the fusion partner of the ALL-1 protein. The ALL-1/AF-6 chimeric protein is the critical product of the t (6:11) abnormality associated with some human leukemia. AF-6 has a GLGF/Dlg homology repeat (DHR) motif and shows a high degree of sequence similarity with Drosophila Canoe, which is assumed to function downstream from Notch in a common developmental pathway. The recombinant N-terminal domain of AF-6 and Canoe specifically interacted with GTP gamma S.GST-Ha-Ras. The known Ras target c-Raf-1 inhibited the interaction of AF-6 with GTP gamma S.GST-Ha-Ras. These results indicate that AF-6 and Canoe are putative targets for Ras.

Amino Acid Sequence↗

Signal transduction pathway of interleukin-4 and interleukin-13 in human B cells derived from X-linked severe combined immunodeficiency patients.

Interleukin-4 (IL-4) and IL-13 are functionally similar cytokines. The functional IL-4 receptor (IL-4R) consists of the IL-4R alpha chain (IL-4R alpha) and the IL-2R gamma chain (gamma c), which is shared by the IL-2, IL-7, IL-9, and IL-15 receptors. The functional IL-13R is thought to involve the IL-4R alpha but not gamma c. In this study, we have analyzed activation of members of the Janus tyrosine kinase (Jak) family and signal transducers and activators of transcription (STAT) 6 induced by IL-4 and IL-13 in Epstein-Barr virus-transformed B cells derived from two patients of X-linked severe combined immunodeficiency, who have mutations of the gamma c gene in the extracellular and intracellular domains. In these B cells, IL-4 failed to induce tyrosine phosphorylation of Jak3 and activation of STAT6, or activation of these molecules was significantly decreased compared with Epstein-Barr virus-transformed normal B cells. In contrast, IL-13 activated STAT6 in these cells as well as normal B cells. However, Jak3 was not activated by IL-13, even in normal B cells. These results clearly indicated that gamma c is essential for activation of Jak3 and STAT6 in the signal transduction pathway of IL-4 in human B cells and that IL-13 does not utilize gamma c but activates STAT6 through an alternative pathway, which is not impaired in B cells of X-linked severe combined immunodeficiency patients.

B-Lymphocytes↗

Distribution of aromatase-immunoreactive cells in the forebrain of zebra finches (Taeniopygia guttata): implications for the neural action of steroids and nuclear definition in the avian hypothalamus.

Cells immunoreactive for the enzyme aromatase were localized in the forebrain of male zebra finches with the use of an immunocytochemistry procedure. Two polyclonal antibodies, one directed against human placental aromatase and the other directed against quail recombinant aromatase, revealed a heterogeneous distribution of the enzyme in the telencephalon, diencephalon, and mesencephalon. Staining was enhanced in some birds by the administration of the nonsteroidal aromatase inhibitor, R76713 racemic Vorozole) prior to the perfusion of the birds as previously described in Japanese quail. Large numbers of cells immunoreactive for aromatase were found in nuclei in the preoptic region and in the tuberal hypothalamus. A nucleus was identified in the preoptic region based on the high density of aromatase immunoreactive cells within its boundaries that appears to be homologous to the preoptic medial nucleus (POM) described previously in Japanese quail. In several birds alternate sections were stained for immunoreactive vasotocin, a marker of the paraventricular nucleus (PVN). This information facilitated the clear separation of the POM in zebra finches from nuclei that are adjacent to the POM in the preoptic area-hypothalamus, such as the PVN and the ventromedial nucleus of the hypothalamus. Positively staining cells were also detected widely throughout the telencephalon. Cells were discerned in the medial parts of the ventral hyperstriatum and neostriatum near the lateral ventricle and in dorsal and medial parts of the hippocampus. They were most abundant in the caudal neostriatum where they clustered in the dorsomedial neostriatum, and as a band of cells coursing along the dorsal edge of the lamina archistriatalis dorsalis. They were also present in high numbers in the ventrolateral aspect of the neostriatum and in the nucleus taeniae. None of the telencephalic vocal control nuclei had appreciable numbers of cells immunoreactive for aromatase within their boundaries, with the possible exception of a group of cells that may correspond to the medial part of the magnocellular nucleus of the neostriatum. The distribution of immunoreactive aromatase cells in the zebra finch brain is in excellent agreement with the distribution of cells expressing the mRNA for aromatase recently described in the finch telencephalon. This widespread telencephalic distribution of cells immunoreactive for aromatase has not been described in non-songbird species such as the Japanese quail, the ring dove, and the domestic fowl.

Animals↗