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K Haraguchi

Publications and source records attributed to K Haraguchi.

At least 19 recordsLinked to original sources
PubMed1992

Single subunit structure of the human thyrotropin receptor.

We have produced rabbit antibody against a synthetic peptide corresponding to N-terminal region of the extracellular domain of human thyrotropin receptor (hTSH-R) (N peptide, aminoacid residues 29-57). Western blot analysis revealed that N-peptide antibody recognized recombinant hTSH-R stably expressing in CHO-K1 cells as a mol. wt. about 104 kDa regardless in the presence or absence of disulfide-reducing agent. The band was not detected in untransfected CHO-K1 cells and no band was also stained by the antibody absorbed with N-peptide. In a reducing condition, the antibody also bound the rat receptor from FRTL5 cells as the same molecular size (104 kDa). These results clearly indicate that TSH-R is composed of a single subunit and that two subunit model for the TSH-R may reflect artifactual proteolytic cleavage of the receptor during membrane preparation.

Amino Acid Sequence↗
PubMed1992

Beta 2-adrenergic receptor mRNA is overexpressed in neoplastic human thyroid tissues.

The expression of beta 2-adrenergic receptor (AR) mRNA was investigated in normal and neoplastic human thyroid tissues. A combination of techniques for reverse transcribing mRNA into cDNA and the incorporation of 32P-gamma ATP into the polymerase chain reaction (PCR)-generated fragments allowed us to detect beta 2-AR mRNA in surgically excised thyroid specimens. The levels of beta 2-AR cDNA generated by PCR in thyroid adenomas and cancers were 3.3 and 6.9 times, respectively, as high as that of normal thyroid tissues. These findings suggest that the level of beta 2-AR mRNA is correlated with the extent of differentiation in neoplastic tissues. The present study provides new insights into the relationships between the AR-adenylate cyclase system and the regulation of the growth and differentiation in neoplastic human thyroid tissues.

Base Sequence↗
PubMed1991

Mouse submandibular gland prorenin-converting enzyme is a member of glandular kallikrein family.

Mouse submandibular gland prorenin-converting enzyme (PRECE) consists of the two polypeptide chains of 17 and 10 kDa and cleaves mouse Ren-2 prorenin at a dibasic site to yield mature renin. Western blot analysis using an antiserum against this enzyme gave rise to multiple bands in mouse submandibular glands, suggesting that PRECE is a member of a protease family. Partial amino acid sequence analysis of purified PRECE and cloning and sequence analyses of its cDNA indicated that it is identical to the mGK-13 gene product, epidermal growth factor-binding protein type B, which is a member of the glandular kallikrein family and is involved in maturation of epidermal growth factor. Conditioned medium from Chinese hamster ovary cells transfected with an expression plasmid for PRECE had prorenin converting activity. These results indicate that PRECE is involved in the maturation of two bioactive polypeptides expressed in mouse submandibular glands, Ren-2 renin and epidermal growth factor.

Amino Acid Sequence↗
PubMed1991

Thyrotropin receptor non-mediated thyroid stimulating immunoglobulin in Graves' disease.

There exists a consensus that hyperthyroid Graves' disease is caused by thyrotropin receptor (TSH-R) autoantibodies. To test the possibility that the TSH-R is the sole antigen for thyroid stimulating antibodies (TSAb), we compared bioactivities of Graves' IgGs between non-thyroid mammalian cells transfected with human TSH-R cDNA and the reference thyroid bioassay. A Graves' IgG with TSH-binding inhibitor immunoglobulin (TBII) activity (89%) markedly stimulated cAMP formation in both CHO-K1 cells transfected with TSH-R cDNA (340 microU/ml of TSH equivalent) and rat thyroid cells, FRTL-5, (410 microU/ml of TSH equivalent). In contrast, a TBII negative (-1.5%) IgG from another patient with Graves' disease showed a strong thyroid stimulating activity (87 microU/ml of TSH equivalent) when FRTL-5 cells were used for the assay. But no stimulating activity was observed in this IgG when CHO-K1 cells transfected with TSH-R cDNA were used, suggesting a possible existence of TSH-R non-mediated thyroid stimulating immunoglobulin in some cases of Graves' disease.

Animals↗
PubMed1991

Carbachol-activated muscarinic (M1 and M3) receptors transfected into Chinese hamster ovary cells inhibit trafficking of endosomes.

We examined the effects of isoproterenol and carbachol on fluid-phase endocytosis by Chinese hamster ovary (CHO) cells transfected with beta-adrenergic, M1, or M3 cholinergic receptors. Isoproterenol increased cAMP production and carbachol increased intracellular Ca, indicating successful expression of the receptor genes and coupling to typical signal transduction pathways. Carbachol inhibited the uptake of horseradish peroxidase (HRP) or Lucifer yellow (markers of fluid-phase endocytosis) in both M1- and M3-containing cells but not in wild-type cells, whereas isoproterenol did not affect pinocytosis in cells transfected with beta-adrenergic receptors. Carbachol inhibited the transit of HRP from an exchangeable pool to a nonexchangeable pool by a latent process requiring minimally 5 min of incubation. During the latent period, only one peak of low-density HRP-containing vesicles was found on Percoll gradients; after 5 min, HRP appeared in both high- and low-density vesicles. Carbachol-treated cells contained less HRP in the high-density fraction enriched in lysosomal markers. Early endosomes from CHO cells labeled for 5 min with HRP underwent fusion to make a more dense population of vesicles in the presence of ATP and KCl at 37 degrees C but not at 4 degrees C. The fused material contained increased levels of G proteins as detected either by ADP ribosylation with appropriate toxins or by immunoblotting with specific antibodies. These findings suggest that GTP binding proteins are internalized in endocytic vesicles and enter into a complex trafficking process involving fusion with other vesicular compartments. Trafficking of endosomes to these compartments is inhibited by activated M1 and M3 muscarinic receptors in CHO cells.

Animals↗
PubMed1991

Two immunologically different isozymes of ascorbate peroxidase from spinach leaves.

Two isozymes of ascorbate peroxidase (AP) from spinach leaves were separated by hydrophobic chromatography and designated AP-I and AP-II. They had similar molecular weights of about 31,000, as determined by gel-filtration, and showed high specificity for ascorbate. One of the two isozymes (AP-II) was purified to homogeneity by SDS-PAGE. Immunoblotting confirmed that antiserum against AP-II reacted with AP-II but not with AP-I. This antiserum inhibited the activity of AP-II, but not that of AP-I. The amino acid composition and partial amino acid sequence of AP-II were determined.

Amino Acid Sequence↗
PubMed1991

Isolation and characterization of recombinant human prorenin in Chinese hamster ovary cells.

Recombinant human prorenin (rh-prorenin) was purified from supernatants of Chinese hamster ovary (CHO) cell line transfected with the cDNA for rh-prorenin by employing a simple two-step procedure which consisted of ammonium sulfate precipitation and immunoaffinity chromatography using a monoclonal antibody specific for the profragment of human prorenin. About 100-fold purification with 35% recovery was achieved after the two steps. Purified rh-prorenin migrated as a single protein band with apparent molecular weights of 46,000-47,000 and about 50,000 on SDS-PAGE and gel filtration (HPLC), respectively, although it consisted of multiple components (pI values, 5.6-6.4) that could be resolved by isoelectric focusing (IEF). The treatment of rh-prorenin with endo-beta-N-acetylglucosaminidase converted the rather broad protein band to a sharp band on SDS-PAGE and reduced the number of multiple pI peaks on IEF. Amino-terminal sequence analysis of both the purified rh-prorenin and rh-renin revealed Leu-Pro-Thr-Asp- and Leu-Thr-Leu-Gly-, respectively, which agreed with those predicted from the base sequences of their cDNA. These data suggested that microheterogeneity of rh-prorenin is due to the carbohydrate moiety, but not to the protein moiety. Purified rh-prorenin was almost inactive, but was cleaved at the carboxyl end of a dibasic pair Lys-2-Arg-1 by trypsin and converted to active renin. However, at the early stage during trypsin activation, new intermediate forms between rh-prorenin and rh-renin were formed, suggesting multiple activation steps of rh-prorenin in addition to the one step activation.

Amino Acid Sequence↗
PubMed1991

[Retropharyngeal hematoma following a bruise of head and neck--a case report and review of literature].

Diseases affecting the retropharyngeal space are relatively uncommon, much less a case of retropharyngeal hematoma. However, a space-occupying lesion in this area can be life threatening and require emergency surgical intervention. There have been 46 cases of retropharyngeal hematoma reported in the English literatures from 1934 to 1989, but there has been no reported case in Japan. Recently we treated a 72-year-old male sustained retropharyngeal hematoma following a bruise of head and neck. The patients was received tracheostomy, antibiotic therapy and intravenous hyperalimentation, and this hematoma was resolved in about 2 weeks. The etiologies, diagnosis, therapies in our case and prognoses of the literature reviewed 47 cases of retropharyngeal hematoma were discussed comprehensively.

Aged↗
PubMed1991

Effects of 3-methylsulphonyl-4,5,3',4'-tetrachlorobiphenyl and 7,8-benzoflavone on aryl hydrocarbon hydroxylase activity in Ah responsive and Ah nonresponsive strains of mice.

In general, C57BL/6NQdj (C57) and DBA/2JCrj (DBA) strains of mice are considered to be the aryl hydrocarbon (Ah) responsive and Ah nonresponsive strains of mice, respectively, which are determined by whether the hepatic aryl hydrocarbon hydroxylase (AHH) activity is enhanced (Ah responsive) or not (Ah nonresponsive) after the treatment of 3-methylcholanthrene (MC). In this study, first, we examined that the Ah responsiveness was systemically regulated in the lungs and kidneys as well as in the liver and observed its systemic control in these three organs in the two strains of mice. Then, we prepared the hepatic microsomes of the two strains of mice after the treatment of MC (42 mg/kg, once), 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD, 20 micrograms/kg, 6 times) and 2,3,4,7,8-pentachlorodibenzofuran (PenCDF 60 micrograms/kg, 6 times) in order to investigate the effects of 3-methylsulphonyl-4,5,3',4'-tetrachlorobiphenyl (3-MSF-TCB, 1.5-45 micrograms/ml) and 7,8-benzoflavone (ANF, 1.4-42 micrograms/ml) on the respective hepatic microsomal AHH activities and the following results were obtained. 1. As compared with the control enzyme activity, TCDD-induced AHH activity was the highest, PenCDF-induced one the second and MC-induced the lowest in both strains of mice. The inductions of the enzyme activity by these chemicals were much more remarkable in the Ah responsive C57 strain than those in the Ah nonresponsive DBA strain. 2. 3-MSF-TCB and ANF enhanced or reduced the enzyme activity depending on both their concentrations and kinds of microsomes, namely, those prepared from untreated control mice and mice treated with MC, TCDD or PenCDF.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

[Elimination of PCDF and PCB congeners in the blood of patients with PCB poisoning in Taiwan].

The blood of 3 Yu-cheng patients sampled from 1980 to 1989 were analyzed for congeners of polychlorinated dibenzofurans (PCDF) and polychlorinated biphenyls (PCB) by high resolution gas chromatography-mass spectrometry and gas chromatography-electron capture detection. The high concentrations of 2,3,4,7,8-penta-, 1,2,3,4,7,8-hexa- and 1,2,3,4,6,7,8-hepta-CDFs (15.4, 37.7 and 4.8 ppb in lipid basis, respectively) were eliminated from the blood at half-lives of 2.14, 2.56 and 2.32 years, respectively. The high concentrations of 8 PCB congeners in the blood were also decreased with time at half-lives of 1.16-4.56 years. The half-lives of retainable PCB congeners were about 2 times longer than those of the PCDF congeners.

Adult↗
PubMed1991

[PCB methyl sulphone: comparison of tissue levels in Baltic grey seals and a Yusho patient].

Methyl sulphone metabolites of PCB and DDE were isolated from different tissues of a Baltic grey seal (Halichoerus grypus). Main components in the seal blubber were identified as 3-MeSO2-2,2',4',5,5'-pentaCB, 4-MeSO2-2,2',4',5,5'-pentaCB, 3-MeSO2-p,p'-DDE, 4-MeSO2-2,2',3',4',5-pentaCB and 4-MeSO2-2,2',3,4',5',6-hexaCB. Liver and lung in the seal contained different MeSO2-PCB pattern compared to all other tissues. These levels in the both tissues were estimated to be 28 and 15 ppm (lipid basis) which corresponded to the same level as the PCB. Concentrations of MeSO2-PCB in any tissues of a Yusho patient were low compared to those in the seal.

Animals↗
PubMed1990

Aryl hydrocarbon hydroxylase activity levels in the hepatic microsomal fraction from MC- or TCDD-treated mice: a comparison between aromatic hydrocarbon responsive and non-responsive strains.

The effects of in vivo administration of polycyclic aromatic hydrocarbons on the levels of aryl hydrocarbon hydroxylase (AHH) activity in aromatic hydrocarbon (Ah) responsive and non-responsive strains of mice were studied using the hepatic microsomal fraction. Injection of 3-methylcholanthrene (MC; 42 mg/kg body wt.) or 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD; 120 micrograms/kg body wt.) into both strains produced marked enhancement of AHH activity except for MC treatment of Ah non-responsive strains. Addition of 7,8-benzoflavone (BNF) to the microsomal AHH assay mixture prepared from mice previously injected with vehicle (olive oil) alone caused an increase in activity when the mice were responsive, while BNF lowered the activity in non-responsive strains. With regard to MC-injected mice, BNF and 3-methyl-sulphonyl-4,5,3',4'-tetrachlorobiphenyl (3-MSF-TCB) decreased microsomal AHH activity in Ah-responsive mice, whereas these drugs enhanced the activity in Ah-non-responsive strains. 3-MSF-TCB also had inhibitory potency on AHH activity, but the mechanism of inhibition seems to be somewhat different from that of BNF. It may also suggest that cytochrome P-450 isozymes inhibited by BNF are different from those inhibited by 3-MSF-TCB.

Animals↗
PubMed1990

Isoproterenol stimulates shift of G proteins from plasma membrane to pinocytotic vesicles in rat adipocytes: a possible means of signal dissemination.

Guanine nucleotide-binding regulatory proteins (G proteins) are linked to a large number of surface membrane receptors and appear to regulate a variety of effector systems located both in the plasma membrane and in other parts of the cell. The mechanism of the disseminative actions of G proteins remains obscure. During an investigation of the fate of two types of G proteins, Gs and Gi, in rat adipocytes, we unexpectedly found that isoproterenol, which stimulates cAMP levels and lipolysis in these cells, induces parallel increases in both Gs and Gi in a low-density microsomal fraction rich in endosomes and Golgi bodies. Two plasma membrane constitutive enzymes, adenylyl cyclase and 5'-nucleotidase, are also elevated in this fraction. NaF and NaN3, metabolic inhibitors, block the redistribution process. The isoproterenol-stimulated shifts are completely reversible after removal of the hormone, indicating a recycling, endocytic process. The endocytic process seems to be fluid phase endocytosis, or pinocytosis, since isoproterenol stimulates the uptake of both fluorescent-labeled dextran and horseradish peroxidase into the same vesicles containing Gs. However, the vesicles that accumulate in response to isoproterenol seem heterogenous in properties that may reflect the lipolytic process induced by isoproterenol. It is speculated that the "pinosomes" formed in response to lipolytic hormones may continually produce signals within the cellular interior during their processing and cycling. Hence, signal production in response to hormones need not be confined to the cell membrane; circulating pinosomes may be responsible for some of the disseminative effects of hormones.

Adenosine Diphosphate Ribose↗
PubMed1990

In vitro effects of methylsulfonyl polychlorinated biphenyls and 7,8-benzoflavone on aryl hydrocarbon hydroxylase activity in human lymphoblastoid cells.

The effects of 11 isomers of methylsulfonyl polychlorinated biphenyls (MSF-PCBs) on the aryl hydrocarbon hydroxylase (AHH) activity were examined at a fixed dose of 1.5 micrograms/ml by using cultured lymphoblastoid cells. One of the isomers 3-MSF-3',4,4',5-tetraCB, as well as 4-MSF-3,3',4',5-tetraCB and 4-MSF-3,3',4',5,5'-pentaCB, effectively reduced the AHH activity when added to the culture medium, especially that previously treated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) to induce the AHH activity. However, the inhibitory potencies exerted by the above three MSF-PCB compounds were smaller than that by 7,8-benzoflavone (BNF). When added to the culture medium simultaneously with TCDD or 3-methylcholanthrene (MC), 3-MSF-3',4,4',5-tetraCB blocked the enhancement of the AHH activity by TCDD but did not that by MC. This is in contrast to BNF which blocked the increases due to both TCDD and MC. On the other hand, 3-MSF-3',4,4',5-tetraCB added directly to the reaction mixture for the TCDD-induced AHH activity showed little influence, while BNF decreased the same activity. These results imply that the effect of 3-MSF-3',4,4',5-tetraCB on the AHH activity is different from that of BNF.

Aryl Hydrocarbon Hydroxylases↗
PubMed1990

[Sensorineural hearing loss following the decompression of the facial nerve].

This study aims to ascertain whether sensorineural hearing loss occurs after the decompression of the facial nerve. Nine patients have undergone decompression of the facial nerve (limited to the vertical segment) by the transmastoid approach were selected as the subjects of this study because the influence of disinfectants and surgical trauma on the inner ear seems to be less severe in this operation than in tympanoplasty. Additionally, this approach seems to be more suitable for judgement of the effect of the drilling noise induced acoustic trauma on the inner ear than tympanoplasty. Though high tone abrupt sensorineural hearing loss was occurred in the operated ear in seven patients, no changes in hearing level were found in the contralateral side ear. Bekesy audiometry performed in only one case revealed Jerger II which suggested some disorder in the cochlea. Not only acoustic trauma induced by the drilling noise but also labyrinthitis occurred via the opened facial canal and the internal ear canal seemed to be the cause of sensorineural hearing loss following the decompression of the facial nerve.

Adult↗