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Biomedical subjects

N Harada

Publications and source records attributed to N Harada.

At least 505 records · Page 28Linked to original sources
PubMed1990

Influence of differences in tumor vascularity upon the effects of hyperthermia.

Utilizing two types of human renal carcinoma heterotransplanted in nude mice, we investigated the variations in hyperthermic effects (42.5 degrees C for 30 min) caused by differences in tumor type with special reference to variations in tumor vascularity. In the hypovascular JRC1 strain, sporadic vascular dilation was observed throughout the tumors after heating. Destruction of tumor cells was observed mainly in the region of dilation. In the hypervascular JRC11 strain, homogenous vascular dilation was observed immediately after heating, mainly at the periphery of tumors. There was a decrease in the viability of cells in the center of the tumor. Therefore, the hypervascular tumors showed greater destruction mainly at the center where blood circulation was reduced. The range of necrosis was also greatly affected by the extent of vascular dilation caused by heating in hypovascular tumors.

Animals↗
PubMed1990

Efficient expression of human beta-interferon in Namalwa KJM-1 cells adapted to serum-free medium by a dhfr gene coamplification method.

We previously reported the expression of human beta-interferon (beta-IFN) (Miyaji et al., 1989) and human lymphotoxin (Miyaji et al., 1990) in Namalwa KJM-1 cells adapted to serum-free medium. To establish an efficient gene expression system, a dihydrofolate reductase (dhfr) gene coamplification method was applied to this cell line. A beta-IFN expression plasmid was introduced with a dhfr expression plasmid into KJM-1 and methotrexate (MTX)-resistant derivatives were selected by a stepwise increase of MTX concentration. Among them, derivatives which showed higher expression levels of beta-IFN than that achieved by the parental transformants were obtained, suggesting that a dhfr gene coamplification method can be used for efficient expression of foreign genes in KJM-1 which contains endogenous dhfr genes. Then, an improved beta-IFN expression vector was constructed, which contains a dhfr transcription unit. This plasmid was introduced into KJM-1 and then, MTX-resistant derivatives were selected. Among them, the highest producer, clone 40-10-24, secreted beta-IFN at a level as high as 5 micrograms/ml, which is about 100-fold higher than that obtained by the G418-resistant parental transformants. In addition, beta-IFN produced by recombinant KJM-1 cells had the same molecular weight of that produced by fibroblasts.

Blotting, Western↗
PubMed1990

Determination of diquat in biological materials by electron spin resonance spectroscopy.

An electron spin resonance (ESR) method already in use for the quantitative analysis of paraquat was applied to the analysis of diquat in blood, serum, urine, tissue homogenates and several drinks without purification of the samples. The diquat radical produced with ascorbic acid at alkaline pH was much more stable than that produced with the commonly used sodium dithionite. Radical decay in solutions covered with n-hexane was less than 5% after 60 min over a wide range of ascorbic acid concentrations. In 0.2 N NaOH solution 85% of the radicals was present even after 24 h. The limit of detection was 0.3 micrograms/ml and the required amount of sample was 0.1 ml. When both diquat and paraquat were present in a sample the diquat was first extracted with 1-butanol prior to the ESR measurement, because both species were converted to the radicals.

Diquat↗
PubMed1990

Monosomy for 21pter-q21: case report and assignment of a DNA clone (Fr8-77) to the deleted segment.

A 4-month-old Japanese girl with partial monosomy 21 was described. The patient has craniofacial anomalies, a short neck, wide-set nipples, anal atresia, deformed feet, hypertonia, intrauterine growth retardation, and mental deficiency. RFA- and high-resolution GTG-banding chromosome analyses, and Southern- and slot-blot analyses interpreted her karyotype as 45,XX,-2,-21, + der(2)t(2:21)(q37.3;q22.1). The origin of this de novo translocation ascertained by analyses with both QFQ-heteromorphisms and a Fr8-77/BamHI RFLP was paternal. Comparison of the patient with previously reported patients confirmed that her manifestations are consistent with those of monosomy for 21pter-q21. Based on the results of molecular analyses on the present patient, a DNA clone, Fr8-77 (D21S82), was assigned to pter-q21.

Chromosome Deletion↗
PubMed1990

Transforming growth factor-beta 1 modulates the effect of 1 alpha, 25-dihydroxyvitamin D3 on leukemic cells.

The human leukemic cells HL-60, U937, KG-1 and THP-1 incubated with transforming growth factor-beta 1 (TGF-beta 1) were studied by examining cell surface antigens and macrophage-specific activities. The addition of 0.5 ng/ml (20 pM) of TGF-beta 1 with 1 alpha, 25-dihydroxyvitamin D3 [1 alpha, 25(OH)2D3] induced more Leu-M3 (CD14)-positive cells (approximately 80%) than 5 X 10(-8) M 1 alpha, 25(OH)2D3 alone did (30 to 50%), although original HL-60 cells did not express any Leu-M3 antigen at all. Tumor necrosis factor-alpha (TNF-alpha) with TGF-beta 1 and 1 alpha, 25(OH)2D3 was found to potentiate the expression of these surface antigens. Furthermore, the phagocytic activity was also induced strongly. The expression of CR3 (CD11b) antigen was also increased, and all Leu-M3-positive cells were found CR3-positive when HL-60, U937, and THP-1 cells were treated with these stimulants. In contrast, CR3 but not Leu-M3 was induced in KG-1 cells after the same treatment. This may indicate that the responsiveness of leukemic cells to TGF-beta 1 and 1 alpha, 25(OH)2D3 might vary depending on a differentiation stage of the target cells. Furthermore, K562 cells originated from a more undifferentiated precursor, were not able to respond to these two inducers. These results suggested that some of TGF-beta superfamily proteins might represent potent modulators in hematopoiesis, especially in the development of monocytes-macrophages or their precursors.

Antigens, Surface↗
PubMed1990

Bilateral intrahepatic lithiasis without extrahepatic bile duct stones.

Bilateral intrahepatic lithiasis is a rare condition, and for this reason a nationwide survey was conducted. Reports on 675 patients with bilateral intrahepatic lithiasis over a 10-year-period were collected. Among these, 258 patients with bilateral intrahepatic lithiasis having no extrahepatic bile duct stones were analyzed. The peak incidence was seen in the fourth to sixth decades. Males and females were equally effected. The stones removed were mainly calcium bilirubinate stones (75.6%). The main clinical symptoms were abdominal pain, fever and jaundice. Charcot's triad was seen in 29.7%, while 12.4% of the patients had no symptoms. Visualization of each segmental duct of the liver by direct cholangiography was excellent in this survey and ranged from 88 to 97.3% of the patients. The most frequent site of stones was the left hepatic duct (60.1%). The site of bile duct dilatation coincided with the location of stones. The most common sites of stenosis were the central part of the lateral segmental duct (32.5%) and the left hepatic duct (37.6%). Hepatic resection was employed in 49.2% of the patients, and drainage procedures were added in 95.6%. Follow-up studies of 236 patients treated by surgery revealed good results in 67.4%, fair in 13.6%, and poor in 7.6%. In these patients, however, endoscopic lithotomy was often employed intra- and/or post-operatively. Conducting hepatic resection, with adequate biliary drainage procedure and cholangiofiberscopic lithotomy may help to improve the therapeutic results of bilateral intrahepatic lithiasis.

Adult↗
PubMed1990

Interleukin-4 receptors on human blood mononuclear cells.

We have studied regulation of the expression of the interleukin-4 receptor (IL-4R) on human blood mononuclear cells (PBMC) using both 125I-IL-4 binding assay and flow cytometric analysis of biotinylated IL-4 (B-IL-4) binding. PBMC express approximately 300 high-affinity IL-4R per cell (Kd = 25-100 pM). Activation of PBMC for 60-80 hr by phytohemagglutinin (PHA) or concanavalin A (Con A) results in a 2- to 4.5-fold increase of IL-4R number without alteration of IL-4R affinity for IL-4. Binding of B-IL-4 showed that IL-4R expression is upregulated on virtually all PHA-stimulated PBMC, whereas it mostly concerns larger cells among Con A-activated PBMC. Reculture of PHA-blasts with 1 nM IL-4 further upregulates IL-4R expression to a level approximately 10-fold higher than observed on freshly isolated PBMC. Interestingly, IL-4 is able to reinduce high IL-4R levels on cells that have been deprived of IL-4 for 20 hr and IL-2 is almost as efficient. Finally, SDS-PAGE analysis of IL-4-binding molecules on unstimulated, PHA- and PHA/IL-4-activated PBMC revealed the same three peptides of MW 140-130, 80-75, and 70-65 kDa, as shown on human cell lines.

Biotin↗
PubMed1990

Expression cloning of a cDNA encoding the murine interleukin 4 receptor based on ligand binding.

Interleukin 4 (IL-4) is a potent mediator of growth and differentiation for various lymphoid and myeloid cells. To isolate a cDNA encoding the murine IL-4 receptor, we have developed an expression cloning method that uses biotinylated ligand as a probe and that may be generally applicable to cloning of receptor genes. COS-7 cells transiently transfected with the cloned full-length cDNA bind murine IL-4 specifically with a Kd = 165 pM. Crosslinking of 125I-labeled IL-4 to COS-7 cells transfected with the cDNA reveals binding to proteins of 120-140 kDa. IL-4-responsive cells also express IL-4-binding proteins of 120-140 kDa but show additional bands at 60-70 kDa; the relationship of the smaller proteins to the larger ones is unclear. The nucleotide sequence indicates that the full-length cDNA encodes 810 amino acids including the signal sequence. While no consensus sequence for protein kinases is present in the cytoplasmic domain, a sequence comparison with the erythropoietin receptor, the IL-6 receptor, and the beta chain of the IL-2 receptor reveals a significant homology in the extracellular domain, indicating that the IL-4 receptor is a member of a cytokine receptor family.

Amino Acid Sequence↗
PubMed1990

Molecular cloning of a cDNA encoding the human interleukin 4 receptor.

Using the mouse interleukin 4 (IL-4) receptor cDNA as a probe, we isolated a cDNA encoding the human IL-4 receptor (hIL-4 receptor) from a multifactor-responsive human myeloid cell line, TF1. The cDNA encodes for an open reading frame of 825 amino acids including a signal sequence (25 amino acids), the external domain (207 amino acids), a transmembrane domain (24 amino acids), and a large cytoplasmic domain (569 amino acids). The human IL-4 receptor has a 65% identity with the mouse IL-4 receptor at the nucleic acid level and retains the typical structural motif of the previously described cytokine receptor family. COS7 cells transfected with the full-length cDNA expressed high levels (140,000 sites/cell) of IL-4 binding sites, with a Kd = 80 pM, an affinity identical to that of the original TF1 cells. Similar to IL-4 responsive cells, cross-linking of [125I]IL-4 to COS7 cells transfected with the cDNA showed a major protein of 130-150 kd and minor species of 55-85 kd.

Amino Acid Sequence↗
PubMed1990

Assessment of autonomic nervous function in patients with vibration syndrome using heart rate variation and plasma cyclic nucleotides.

A case-control study was performed to investigate the autonomic nervous function in vibration syndrome. The subjects were 20 patients with a history of Raynaud's phenomenon (vibration white finger (VWF) (+) group), 20 patients without such a history (VWF(-) group), and 20 healthy workers (control group). Their ages and years under medical treatment for vibration syndrome were matched individually among the groups. They were examined using the test of R-R interval variations in the electrocardiogram at rest and during deep breathing and the test of plasma cyclic nucleotide (cyclic AMP and cyclic GMP) responses to whole body exposure to cold. The heart rate variation resulting from respiratory arrhythmia reflects parasympathetic activity; the changes of plasma cyclic AMP and GMP levels reflect sympathetic and parasympathetic receptor functions. The reduced R-R interval variations were observed in the VWF(+) group. Although exposure to cold induced a significant increase of plasma cyclic AMP level, the percentage increase was almost the same among the three groups. The response of plasma cyclic GMP level to cold exposure was highly activated in the VWF(+) and the VWF(-) groups. On the basis of these results, it is considered that the parasympathetic function of patients with vibration syndrome is lower at rest, and that exposure to cold induces a hypperresponse of the parasympathetic nervous system and the alpha-2 adrenergic mechanism as a result of activation of the sympathetic nervous system. Moreover, in patients with VWF, the contribution of the alpha-2 adrenergic mechanism is presumably larger than that in the patients without VWF.

Autonomic Nervous System↗
PubMed1990

Immunoelectron microscopic localization of aromatase in human placenta and ovary using microwave fixation.

In this study we investigated the immunohistochemical localization of a unique aromatase, a single protein of 51,000 daltons, in the human placenta and ovary at light and electron microscopic levels. Microwave fixation was adopted for the immunoelectron microscopic study because it is an excellent method for preserving antigenicity and subcellular structures in frozen sections. Tissue samples from four immature human placentas, four full-term human placentas, and two human ovaries fixed in 10% formalin were examined by light microscopy. In addition, tissues from three full-term human placentas and one immature human placenta fixed in 4% paraformaldehyde were examined by electron microscopy. By light microscopy, immunoreactivity for this aromatase was located in the syncytiotrophoblast and a part of the cytotrophoblast of the placenta and in the lutein and granulosa cells of the ovary. Immunoelectron microscopy revealed that the aromatase antigen was localized on the surface of the microvilli, the lateral plasma membrane, and in the endoplasmic reticulum (ER) in the syncytiotrophoblast of the placenta. The positive immunoreactivity in the syncytiotrophoblast ER is consistent with previous results using antibodies for other types of aromatase, whereas the reactivity on the microvilli has not been previously described. The present report describes the fine localization of this unique aromatase in placental and ovarian tissues; its localization on the plasma membranes requires further physiological investigation.

Adult↗
PubMed1990

Hormonal responses to cold exposure in subjects with vibration syndrome.

Responses of the autonomic nervous system and the endocrine system to cold exposure were investigated. The subjects were all males, between 41 and 69 years of age. Seventy subjects with the vibration syndrome and vibration-induced white finger (VWF(+) group), 70 subjects with the vibration syndrome without VWF (VWF(-) group) and 70 healthy subjects (control group) were individually matched according to age. The subjects remained in a cold room at 7 C for 30 minutes. Catecholamines, cyclic nucleotides, thyroid hormones, ACTH and cortisol were measured before and during cold exposure. The VWF(+) group and the VWF(-) group had larger % increases of plasma norepinephrine, cyclic AMP, cyclic GMP, T3 and T4 levels than the control group. These findings indicate that the responses of the autonomic nervous system and the thyroid system to cold exposure are greater in the subjects with the vibration syndrome.

Adrenocorticotropic Hormone↗
PubMed1990

Effects of combined use of roxatidine and pirenzepine on gastric secretion in humans.

We examined the effects of the combined use of H2-receptor antagonist (roxatidine) and muscarinic receptor antagonist (pirenzepine) by oral administration on gastric juice and acid secretion in humans. The volume, pH level, and acidity of gastric juice were determined in the sample collected at 9:00 AM 10 hr after either the oral administration of 150 mg of roxatidine or the combined administration of 150 mg of roxatidine and 50 mg of pirenzepine. Significant decrease in volume and acidity and increase in pH were observed in both roxatidine group and combined group compared with control placebo group, but significant difference were not observed in gastric pH and acidity between roxatidine group and combined group. The volume of gastric juice was decreased significantly by the combined administration in comparison with the sole administration of roxatidine. Consequently, the combined oral administration of the two agents was considered to be more effective than the sole administration of roxatidine for clinical cases which require stronger suppression of gastric secretion at the night.

Adult↗
PubMed1990

Production of interleukin-6 from macrophages by MDP-Lys (L 18), romurtide.

N2-[(N-Acetylmuramoyl)-L-alanyl-D-isoglutaminyl-N6-stearoyl-L-lysine [MDP-Lys(L18), romurtide] is an immunopotentiating substance. In addition to neutrophilic leukocytosis, the effects previously found after the administration of this compound in both mice and humans were thrombocytosis and elevated levels of colony-stimulating factor (CSF) in peripheral blood. Although the exact mechanism of thrombopoiesis is not yet known, evidence has been accumulating that interleukin-6 (IL-6) plays an important role in the maturation of megakaryocytes, and the administration of IL-6 has been reported to induce a significant increase in blood platelets associated with promotion of megakaryocyte maturation. We measured the IL-6 levels in the culture supernatants of peripheral blood mononuclear cells (PBMCs), adherent cells and nonadherent cells in the presence of romurtide. Significant augmentation of IL-6 from PBMCs and adherent cells, but not nonadherent cells, was observed in the presence of romurtide in vitro.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1990

[A case with reconstruction of the floor of the oral cavity and mandibular region with the D-P flap after resection of giant keloid and radiation scar of the mandibular].

The floor of the oral cavity and mandibular of a 27-year-old female was reconstructed with the D-P flap after resection of a giant keloid in the submandibular region and a radiation scar of the mandibular. The mandibular was reconstructed with a transplantation graft of the iliac bone and the functional properties and appearance were good.

Adult↗
PubMed1990

Leprosy and malignancy: autopsy findings of 252 leprosy patients.

The occurrence of malignant tumors in leprosy patients was studied in 252 autopsied cases. Malignant tumors were found in 33 out of 110 autopsy cases from 1962 to 1971, and in 51 out of 141 autopsy cases from 1977 to 1989 (until July). In 1974, a lepromatous case with Kaposi's sarcoma was autopsied. The incidence of malignant tumors in our 252 cases were 33.7% (85 out of 252). Carcinoma of the alimentary system was most common: stomach, liver and large intestine, in that order. There was an increased number of hepatocellular carcinoma closely related to liver cirrhosis. Carcinoma of the lung has increased remarkably in leprosy patients quite recently. Malignant lymphoma was the most common of the nonepithelial malignant tumors, and four of these cases were seen in lepromatous leprosy patients. Eight cases showed double or triple cancers; seven of these were autopsied during 1977 to 1989. Further studies should be done to ascertain which types of leprosy showed the highest incidence, and which sex showed more frequent malignant tumors.

Aged↗