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Biomedical subjects

H Kawashima

Publications and source records attributed to H Kawashima.

At least 253 records · Page 14Linked to original sources

Carbohydrate binding specificities of several poly-N-acetyllactosamine-binding lectins.

The structural requirements for the interaction of the Asn-linked poly-N-acetyllactosamine-type oligosaccharide moieties of glycoproteins with various N-acetylglucosamine-binding lectins were investigated by means of affinity chromatography on immobilized lectin-Sepharose columns. High molecular weight glycopeptides containing poly-N-acetyllactosamine-type oligosaccharides obtained by Pronase digestion of human erythrocyte ghosts were treated with 0.1 M trifluoroacetic acid at 100 degrees C for 40 min and then several oligosaccharide fragments were purified with an amino-bonded silica column. Among these oligosaccharide fragments, trisaccharide Gal beta 1-4GlcNAc beta 1-6Galol bound to the wheat germ agglutinin (WGA)- and pokeweed mitogen (PWM)-Sepharose columns, and also showed affinity to the Datura stramonium agglutinin (DSA)-, Lycopersicon esculentum (tomato) agglutinin- and Solanum tuberosum (potato) agglutinin-Sepharose columns. Pentasaccharide Gal beta 1-4GlcNAc beta 1-3(Gal beta 1-4GlcNAc beta 1-6)Galol showed weaker affinity to the WGA- and PWM-Sepharose columns, compared to the trisaccharide. Trisaccharide GlcNAc beta 1-3(GlcNAc beta 1-6)Galol showed weak affinity to the WGA-Sepharose column and did not show any affinity to the other lectin-Sepharose columns. Hexasaccharide Gal beta 1-4GlcNAc beta 1-3Gal beta 1-4GlcNAc beta 1-3Gal beta 1-4GlcNAcol bound only to the DSA-Sepharose column, indicating that only DSA does not require a GlcNAc beta(1-6)- linkage for interaction.

Carbohydrate Metabolism↗

Production of circulation interferon in children with varicella.

Interferon (IFN) alpha was detected in the serum of children with varicella. The serum IFN was demonstrated in the acute phase of varicella and became negative 7 days after the onset of rash. Serum IFN was detected during the incubation period in two patients tested before the onset of rash. Some correlation was shown between the positive rate of circulating IFN and the severity of illness.

Acute Disease↗

Effects of a new immunosuppressive agent, FK 506, on the efferent limb of the immune responses.

The effects of a novel immunosuppressant, FK 506, on the efferent limb of the immune response were studied in the experimental autoimmune uveoretinitis (EAU) in the rat, using two different treatment schedules. First, rats actively immunized with S-antigen were treated with FK 506 only after the onset of EAU. FK 506 (1 or 3 mg kg-1 day-1) reduced the intensity of EAU as compared to that of non-treated rats. Especially, a daily dose of 3 mg kg-1 completely suppressed further development of EAU. It is, therefore, suggested that FK 506 treatment is effective in suppressing the ongoing process of the immune response, even after the disease has been initiated. Second, FK 506 (0.3 mg kg-1 day-1) was given only to the recipient rats which received IRBP-sensitized lymphocytes. None of FK 506-treated recipients developed EAU, while all control recipients developed the disease approximately 4 days after the cell transfer. The immune responses of FK 506-treated rats in the two experiments were also significantly suppressed. The antibody levels to S-antigen, the antigen-specific proliferative responses of lymphocytes, and even the proliferative responses to Con A were markedly suppressed in the rats in which FK 506 was given only during the efferent limb of the immune response.

Animals↗

Effects of 2,2'-azobis (2-amidinopropane) hydrochloride in vivo and protection by vitamin E.

2,2'-Azobis (2-amidinopropane) hydrochloride (AAPH), a compound that decomposes spontaneously to generate free radicals, was administered intraperitoneally to rats. High doses (greater than or equal to 70 mg/kg) were always fatal within a few hours. At nonlethal levels, AAPH was found to be absorbed into the circulation where it remained with a half-life of about 30 min. Lipid peroxidation was observed to occur in the liver and, to a much smaller extent, the kidney and heart of treated rats; levels of thiobarbituric acid-reactive substances were unchanged in the lung and brain, and significantly reduced in the plasma. Serum lipid levels were also lower in the AAPH-treated rats. Orally administered vitamin E, but not its water soluble analog, prevented the accumulation of TBA-reactive substances in the livers of AAPH-treated rats in a dose-dependent manner, but had no effect on mortality or the changes in serum lipid levels. The data suggest that intraperitoneally administered AAPH is absorbed into the circulation and can induce lipid peroxidation in vivo, but that toxicity may also arise through nonradical mechanisms. Furthermore, the free radical toxicity of AAPH in vivo may not be so general as previously suggested.

Amidines↗

Mutational analysis of structure--activity relationships in human tumor necrosis factor-alpha.

To determine the region of human tumor necrosis factor-alpha (TNF-alpha), essential for cytotoxic activity against mouse L-M cells, single amino-acid-substituted TNF-alpha mutant proteins (muteins) were produced in Escherichia coli by protein engineering techniques. An expression plasmid for TNF-alpha was mutagenized by passage through an E. coli mutD5 mutator strain and by oligonucleotide-directed mutagenesis. Approximately 100 single amino-acid-substituted TNF-alpha muteins were produced and assayed for cytotoxic activity. The cytotoxic activities of purified TNF-alpha muteins, e.g. TNF-31T, -32Y, -82D, -85H, -115L, -141Y, -144K and -146E, were less than 1% of that of parent TNF-alpha. These results indicate that the integrity of at least four distinct regions of the TNF-alpha molecule is required for full biological activity. These regions are designated as follows: region I, from position 30 to 32; region II, from position 82 to 89; region III, from position 115 to 117; region IV, from position 141 to 146. In addition, TNF-141Y could not completely compete with parent TNF-alpha for binding to the receptor. This demonstrates that region IV, and at least aspartic acid at position 141, must be involved in the TNF receptor binding site.

Amino Acid Sequence↗

A new method for induction of experimental autoimmune uveoretinitis (EAU) in mice.

Experimental autoimmune uveoretinitis (EAU) was induced in two strains of mice by repeated-immunization protocol. SMA mice (H-2 nondefined) and C57BL/6 mice (H-2b) were immunized with S-antigen mixed with Klebsiella 03 lipopolysaccharide (K03 LPS) repeatedly at intervals of 1 to 4 weeks. Following the tertiary immunization, the mice exhibited histopathological changes of EAU as well as significant immune responses to the antigen. The antigen doses required for successful EAU induction were 4 micrograms or more at each immunization time. The histopathology of EAU was characterized by mild infiltration of mononuclear cells in the retina and the choroid, particularly, at the retinal blood vessels and the photoreceptor cell layer. The anterior segment of the eye was not affected by inflammation, and therefore clinical signs of EAU were not detected even under an operating microscope. Since the mouse is a genetically and immunologically well-defined species, this model is useful for study of immunopathogenic mechanisms of EAU.

Adjuvants, Immunologic↗

Effects of FK506, 15-deoxyspergualin, and cyclosporine on experimental autoimmune uveoretinitis in the rat.

The effects of two novel immunosuppressants, FK506 and 15-deoxyspergualin (15-DSG), on experimental autoimmune uveoretinitis (EAU) were evaluated in the rat. Rats were immunized with retinal soluble antigen (S-antigen) and treated with FK506 or 15-DSG, and the disease induction as well as the immune responses to the antigen were examined. The results were compared with animals treated with cyclosporine (CsA) which has been widely used to treat refractory uveitis in humans. A dose-response study showed that FK506 suppressed EAU induction at doses 10-30 times lower CsA when given on days 0-14 postimmunization, while 15-DSG suppressed the disease development at doses very similar to CsA. As with CsA, FK506 suppressed EAU induction when given only in the induction phase (days 0-5 postimmunization) or in the effector phase (days 7-12), but at doses much lower than CsA. On the other hand, 15-DSG suppressed EAU only at toxic doses with these schedules. The antigen specific mitotic response of lymphocytes was markedly suppressed by the three agents, while the antigen specific antibodies in sera were suppressed by 15-DSG and FK506 but not by CsA at doses effective in suppressing the disease induction. More significant findings were uniquely prolonged immunosuppressive effects of FK506: EAU induction as well as the immune responses to S-antigen were suppressed long after the cessation of drug treatment.

Animals↗

[A case of asynchronous triple primary malignant tumors of bladder, stomach and lung].

An asynchronous case of triple primary malignant tumors of bladder, stomach and lung was reported. The patient was treated by total cystectomy and ileal conduit plasty for a bladder tumor in 1978 and subtotal gastrectomy and Billroth-I plasty for a gastric cancer in 1984. In 1987, a lung cancer was found and the biopsy revealed a small cell carcinoma. Though combined chemotherapy was done, he died from the lung cancer 2 years later. Fulfilling the Warren and Gate's criteria, this case may be said to be an asynchronous case of triple primary cancers.

Adenocarcinoma↗

Antigen-specific suppressor cells induced by FK506 in experimental autoimmune uveoretinitis in the rat.

The authors previously reported that FK506 effectively suppressed the induction of experimental autoimmune uveoretinitis (EAU) in rats with much lower doses than cyclosporine A. This study was aimed at analyzing the immune status of the FK506-treated and EAU-suppressed rats and examining the hypothesis whether the agent could induce antigen-specific suppressor T (Ts) cells. It was found that spleens from S-antigen-immunized and FK506-treated rats contained a population of Ts cells inhibiting the proliferative responses of S-antigen-sensitized lymphocytes to S-antigen, yet these cells did not affect the proliferative responses of interphotoreceptor retinoid-binding protein (IRBP)-sensitized lymphocytes to IRBP. The helper T (Th) cells did not exhibit such suppressor activities. Furthermore, transfer of Ts cells from S-antigen-immunized and FK506-treated rats to naive syngenic rats induced partial inhibition of EAU induction or delay of EAU onset after immunizing the recipient rats with S-antigen. Lymphocytes from the EAU-suppressed recipients showed low proliferative response to S-antigen and low levels of antibody to S-antigen. These data thus indicate that FK506 treatment after S-antigen immunization induces an activation of Ts cells specific to S-antigen and that the Ts cells might contribute, at least in part, to the uniquely prolonged and intensive immunosuppression by FK506.

Animals↗

Molecular definition of a region of chromosome 21 that causes features of the Down syndrome phenotype.

Down syndrome (DS) is a major cause of mental retardation and heart disease. Although it is usually caused by the presence of an extra chromosome 21, a subset of the diagnostic features may be caused by the presence of only band 21q22. We now present evidence that significantly narrows the chromosomal region responsible for several of the phenotypic features of DS. We report a molecular and cytogenetic analysis of a three-generation family containing four individuals with clinical DS as manifested by the characteristic facial appearance, endocardial cushion defect, mental retardation, and probably dermatoglyphic changes. Autoradiograms of quantitative Southern blots of DNAs from two affected sisters, their carrier father, and a normal control were analyzed after hybridization with two to six unique DNA sequences regionally mapped on chromosome 21. These include cDNA probes for the genes for CuZn-superoxide dismutase (SOD1) mapping in 21q22.1 and for the amyloid precursor protein (APP) mapping in 21q11.2-21.05, in addition to six probes for single-copy sequences: D21S46 in 21q11.2-21.05, D21S47 and SF57 in 21q22.1-22.3, and D21S39, D21S42, and D21S43 in 21q22.3. All sequences located in 21q22.3 were present in three copies in the affected individuals, whereas those located proximal to this region were present in only two copies. In the carrier father, all DNA sequences were present in only two copies. Cytogenetic analysis of affected individuals employing R and G banding of prometaphase preparations combined with in situ hybridization revealed a translocation of the region from very distal 21q22.1 to 21qter to chromosome 4q. Except for a possible phenotypic contribution from the deletion of chromosome band 4q35, these data provide a molecular definition of the minimal region of chromosome 21 which, when duplicated, generates the facial features, heart defect, a component of the mental retardation, and probably several of the dermatoglyphic changes of DS. This region may include parts of bands 21q22.2 and 21q22.3, but it must exclude the genes S0D1 and APP and most of band 21q22.1, specifically the region defined by S0D1, SF57 and D21S47.

Adult↗

A human IL-1 alpha derivative which lacks prostaglandin E2 inducing activity and inhibits the activity of IL-1 through receptor competition.

In order to segregate multiple activities ascribed to IL-1, various human IL-1 alpha derivatives were produced by recombinant DNA technology. A derivative substituted at the 151st Asp with Tyr(termed to be TN-55) showed unique characteristics. TN-55 lost the PGE2 inducing activity in a human osteosarcoma cell line (MG-63) and growth promoting activity for a human dermal fibroblast cell line (CCD-27Sk), but partially remained LAF activity in mouse thymocyte, cytostatic activity against a human melanoma cell line (A-375) and IL-2 inducing activity in a human T cell line (HSB.2). Although TN-55 bound to the receptor on MG-63 cells with a similar affinity as native IL-1 alpha, TN-55 not only failed in inducing PGE2 production but also antagonized the PGE2 inducing action of IL-1 alpha or IL-1 beta. Thus, TN-55 seems to work as a receptor antagonist. Moreover, TN-55 did not stimulate ACTH secretion in rats in vivo. On the other hand, TN-55 induced PGE2 production in a rabbit dermal fibroblast cell line (RAB-9) and exhibited pyrogenicity in rabbits in vivo. These data suggest that TN-55 has different species-cross reactivity from native IL-1 alpha. In conclusion, multiple biological activities of IL-1 alpha can be segregated by substituting one amino acid. TN-55 may be an ideal IL-1 agonist which lacks inflammatory characteristics of IL-1 (e.g. PGE2-dependent activities) in human but partially retained T lymphocyte stimulating activity and tumor cytostatic activity. In addition, TN-55 may also work as an IL-1 antagonist to block PGE2 production induced by IL-1 through receptor competition.

Adrenocorticotropic Hormone↗

[A case report of emphysematous pyelonephritis].

A 51-year-old male patient with diabetes mellitus consulted his home doctor because of high fever and right flank pain. Urinalysis showed marked pyuria. Treatment with antibiotics was not completely effective, and he was referred to our hospital for further examination and treatment. CT scan showed an abnormal gas shadow in right renal parenchyma. He was diagnosed with emphysematous pyelonephritis and right subcapsular nephrectomy was done after the control of diabetes mellitus. We reviewed 57 cases of emphysematous pyelonephritis including our case in the Japanese literature, and we discussed about its etiology, symptomatology, choice of treatment and prognosis.

Diabetic Nephropathies↗

Cholescintigraphic observation of the sphincter of Oddi motor activity in patients with gallstone.

In 36 cases with gallstones, biliary scintigraphy was performed before and after operation to prepare the time-activity curve in the juxta-papillary duodenum. This curve showed different patterns depending on the conditions of disease, and seemed to represent on aspect of the sphincter of Oddi phasic activity, in view of the exerted effect of caerulein administration. This method is useful as a non-invasive one for the diagnosis of dynamic function of the sphincter of Oddi.

Ampulla of Vater↗

Comparison of phosphofructokinases in submandibular glands of immature and adult rats.

1. Phosphofructokinases (PFKs) in immature and adult rat submandibular glands were purified to near homogeneity, and their properties were compared. 2. PFK in immature gland was less sensitive to inhibition by ATP than adult PFK. 3. Saturation curve for fructose 6-phosphate of PFK in immature gland was less sigmoidal than that of adult PFK indicating the lower cooperativity of subunits in immature PFK. 4. Fructose 2,6-bisphosphate relieved PFK from inhibition by ATP in adult gland, but a similar effect was not clearly observed in immature gland PFK. 5. Adult PFK was a heterotetramer consisting of C-, M-, L-subunits, but in immature PFK another type of subunit, which was slightly smaller than L-subunit, existed in addition to C-, M- and L-subunits.

Adenosine Triphosphate↗

Isolation of a new form of cytochrome P-450 with prostaglandin A and fatty acid omega-hydroxylase activities from rabbit kidney cortex microsomes.

Two different forms of cytochrome P-450, highly active in the omega-hydroxylation of prostaglandin A, and the omega- and (omega-1)-hydroxylation of fatty acids (P-450ka-1 and P-450ka-2), have been purified from kidney cortex microsomes of rabbits treated with di(2-ethylhexyl)-phthalate. On the basis of the peptide map patterns and NH2-terminal amino acid sequence, P-450ka-1 was determined to be a new form of omega-hydroxylase cytochrome P-450, whereas P-450ka-2 is identical to P-450ka reported earlier. The first 20 NH2-terminal amino acid sequence (ALNPTRLPGSLSGLLQVAGL) and (ALSPTRLPGSFSGFLQAAGL) of P-450ka-1 and P-450ka-2 showed 90 and 80% homology with that of the lung prostaglandin omega-hydroxylase, respectively, suggesting that these three cytochromes P-450 are members of the same omega-hydroxylase cytochrome P-450 gene family.

Amino Acid Sequence↗

Suppression of serum 1,25-dihydroxyvitamin D in humoral hypercalcemia of malignancy is caused by elaboration of a factor that inhibits renal 1,25-dihydroxyvitamin D3 production.

Although many patients with humoral hypercalcemia of malignancy exhibit reduced serum 1,25-dihydroxyvitamin D [1,25-(OH)2D] levels, N-terminal fragments of recently identified PTH-related protein as well as PTH itself elevate serum 1,25-(OH)2D concentrations. In the present study, the effect of tumor extracts from human tumor-implanted hypercalcemic nude rat models with high and low serum 1,25-(OH)2D on renal 1,25-(OH)2D3 production was examined using rat kidney cells in culture. Whereas tumors from rats with high serum 1,25-(OH)2D levels (OCC rats) contained only a single peak of cAMP production-stimulating activity (CPSA) in osteogenic sarcoma cells on reverse phase HPLC, tumor extracts from rats with low serum 1,25-(OH)2D levels (UCC rats) contained at least two peaks of CPSA. The main peak (peak A) was estimated to be approximately 17K by gel permeation chromatography, which was the same as the molecular size of the hitherto identified PTH-related protein, and a minor peak of CPSA (peak B) was estimated to be about 25K. When peak A or crude extracts of OCC tumors as well as human PTH-(1-34) were added to primary cultures of rat kidney cells, the production of 1,25-(OH)2D3 was significantly stimulated. In contrast, although peak B or crude UCC tumor extracts had no effect on 1,25-(OH)2D3 production in themselves, when they were added together with peak A or human PTH-(1-34) the stimulation of 1,25-(OH)2D3 production was almost completely inhibited. Both peak A and peak B enhanced cAMP production in cultured kidney cells, and the cAMP production by peak A was not affected by peak B. These results are consistent with the possibility that elaboration of an additional factor from tumor cells may be the mechanism by which serum 1,25-(OH)2D levels are suppressed in patients with humoral hypercalcemia of malignancy. The nature as well as the mechanism of action of this factor remain to be elucidated.

Animals↗