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Yamamoto T, Matsumoto K, Kurachi H, Okamoto Y, Nishio Y, Sakata M, Tasaka K, Murata Y. Progesterone inhibits transcriptional activation of human chorionic gonadotropin-alpha gene through protein kinase A pathway in trophoblast cells. Mol Cell Endocrinol 2001; 182:215-24. [PMID: 11514056 DOI: 10.1016/s0303-7207(01)00580-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The purpose of this study was to analyze the mechanism of transcriptional inhibition of human chorionic gonadotropin-alpha (hCGalpha) gene by progesterone in trophoblast cells. We stably transfected -290 bp hCGalpha promoter-CAT constructs (-290halphaCAT) into Rcho-1 cells and monitored the promoter activities. Differentiation-dependent activation of -290 bp hCGalpha promoter containing a tandem repeat of cAMP response element (CRE) was inhibited by progesterone in a dose-dependent manner. To further analyze the mechanism of the progesterone action, Rcho-1 cells stably transfected with -290halphaCAT were treated with forskolin in the presence of progesterone. Progesterone inhibited forskolin-induced transcriptional activation of hCGalpha gene. Moreover, progesterone inhibited forskolin-induced transcriptional activation of CRE-CRE-tk-CAT. These results suggest that progesterone may inhibit cAMP-induced transcriptional activation of hCGalpha gene through CRE. Although progesterone did not alter the amount of CRE-binding protein (CREB), which is a main transcriptional factor bound to CRE(s) on hCGalpha promoter, progesterone abolished forskolin-induced CREB phosphorylation. In addition, pretreatment with progesterone abolished forskolin-induced activation of nuclear protein kinase A (PKA). In conclusion, progesterone inhibits hCGalpha gene transcription, at least in part, via the CRE region by inhibiting CREB phosphorylation through PKA pathway in trophoblast cells.
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Sakata M, Tsuruha JI, Masuko-Hongo K, Nakamura H, Matsui T, Sudo A, Nishioka K, Kato T. Autoantibodies to osteopontin in patients with osteoarthritis and rheumatoid arthritis. J Rheumatol 2001; 28:1492-5. [PMID: 11469452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
OBJECTIVE Osteopontin (OPN), secreted mainly from chondrocytes, is suggested to be involved in the ossification and remodeling of bone and also in regulation of cytokine profiles. We investigated whether patients with osteoarthritis (OA) and rheumatoid arthritis (RA) display autoimmunity against OPN. METHODS Recombinant human OPN (rhOPN) was prepared as a fusion protein with beta-galactosidase using E. coli. Serum samples from patients with OA or RA and from age matched healthy donors were tested for autoantibodies to rhOPN using ELISA and Western blotting. Reactivity of the same samples to purified native human OPN (nhOPN) was investigated by ELISA separately, to evaluate conformational epitopes. RESULTS By ELISA, autoantibodies to rhOPN were found in one (0.95%) of 105 patients with OA and 2 (2.3%) of 88 patients with RA. These autoantibodies to rhOPN were confirmed by Western blotting. In contrast, 11 (9.5%) of 105 OA serum and 13 (15%) of 88 RA serum samples reacted to nhOPN. The anti-OPN positive RA patients showed high serum levels of rheumatoid factor and C-reactive protein and accelerated erythrocyte sedimentation rate compared to the anti-OPN negative group, although the differences did not achieve statistical significance. CONCLUSION Our data showed that OPN is one of the autoantigens in OA and RA. Preferential recognition of nhOPN to rhOPN indicates that major epitope(s) of OPN would be conformational. Clinically, existence of the anti-OPN antibodies may be linked to disease severity in RA.
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Shiba H, Uchida Y, Kamihagi K, Sakata M, Fujita T, Nakamura S, Takemoto T, Kato Y, Kurihara H. Transforming growth factor-beta1 and basic fibroblast growth factor modulate osteocalcin and osteonectin/SPARC syntheses in vitamin-D-activated pulp cells. J Dent Res 2001; 80:1653-9. [PMID: 11597027 DOI: 10.1177/00220345010800071101] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Vitamin D deficiency elicits hypocalcified dentin. However, little is known about the action of vitamin D on the syntheses of dentin matrix proteins. In this study, we examined the effects of 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] on the expressions of osteocalcin and osteonectin/secreted protein, acidic and rich in cysteine (SPARC), by human pulp cells in the presence or absence of transforming growth factor-beta1 (TGF-beta1) or basic fibroblast growth factor (bFGF). 1,25(OH)2D3 markedly increased osteocalcin at protein and mRNA levels. The osteocalcin level induced by 1,25(OH)2D3 was decreased and increased by TGF-beta1 and bFGF, respectively. 1,25(OH)2D3 suppressed SPARC synthesis at protein and mRNA levels. TGF-beta1, but not bFGF, increased SPARC synthesis in the presence of 1,25(OH)2D3. SPARC, but not osteocalcin, increased DNA synthesis in pulp cells. These findings suggest that 1,25(OH)2D3 and growth factors interactively regulate the expression of osteocalcin and SPARC in pulp cells, and that SPARC can stimulate DNA synthesis by pulp cells.
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Yuan GH, Masuko-Hongo K, Sakata M, Tsuruha J, Onuma H, Nakamura H, Aoki H, Kato T, Nishioka K. The role of C-C chemokines and their receptors in osteoarthritis. ACTA ACUST UNITED AC 2001; 44:1056-70. [PMID: 11352237 DOI: 10.1002/1529-0131(200105)44:5<1056::aid-anr186>3.0.co;2-u] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE To evaluate the involvement of the chemokine/chemokine receptor system in cartilage degradation in osteoarthritis (OA). METHODS Expression of the 4 C-C chemokines monocyte chemoattractant protein 1 (MCP-1), macrophage inflammatory protein 1alpha (MIP-1alpha), MIP-1beta, and RANTES, and their receptors CCR-2 and CCR-5, was assessed in 11 OA patients and 5 normal controls, by reverse transcriptase-polymerase chain reaction (RT-PCR), enzyme-linked immunosorbent assay (ELISA), immunochemistry, and flow cytometry on untreated or interleukin-1beta (IL-1beta)- and/or tumor necrosis factor alpha (TNFalpha)-stimulated chondrocytes. The effects of these chemokines on the expression of matrix metalloproteinases (MMP) and tissue inhibitor of metalloproteinases were assayed by RT-PCR and ELISA. The effects on proteoglycan synthesis and release were also assayed, using 35S-sulfate incorporation and 35S-proteoglycan release. RESULTS The C-C chemokines and their receptors CCR-2 and CCR-5 were found to be expressed in normal and OA chondrocytes. However, regulation of chemokine expression by IL-1beta and TNFalpha differed between normal and OA chondrocytes. Intracellular staining revealed that approximately 20% of the chondrocytes contained CCR-2 and CCR-5 in the cytoplasm, whereas cell surface expression was detected less frequently. Interestingly, RANTES induced expression of its own receptor, CCR-5, suggesting an autocrine/paracrine pathway of the chemokine within the cartilage milieu. Finally, addition of MCP-1 or RANTES not only induced MMP-3 expression, but also inhibited proteoglycan synthesis and enhanced proteoglycan release from the chondrocytes. CONCLUSION The differential expression of chemokines and their receptors under the regulation of IL-1beta and TNFalpha suggests that the cytokine-triggered chemokine system may play a key role in the cartilage degradation of OA, possibly acting in an autocrine/paracrine manner.
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105
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Sakata M, Todokoro M, Kai T, Kunitake M, Hirayama C. Effect of cationic polymer adsorbent pK a on the selective removal of endotoxin from an albumin solution. Chromatographia 2001. [DOI: 10.1007/bf02493008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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106
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Uchida Y, Shiba H, Komatsuzawa H, Takemoto T, Sakata M, Fujita T, Kawaguchi H, Sugai M, Kurihara H. Expression of IL-1 beta and IL-8 by human gingival epithelial cells in response to Actinobacillus actinomycetemcomitans. Cytokine 2001; 14:152-61. [PMID: 11396993 DOI: 10.1006/cyto.2001.0863] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The interaction between epithelial cells and microorganisms is the most important step in bacterial infections. Epithelial cells in response to exposure to pathogenic bacteria produce cytokines that initiate inflammation. However, little is known about the cytokine response of gingival epithelial cells to periodontopathogenic bacteria. Actinobacillus actinomycetemcomitans is thought to play a significant role in the initiation of periodontitis because of its bacteriological characteristics. In the present study, we investigated the cytokine induction by human gingival epithelial cells (HGEC) following exposure to A. actinomycetemcomitans in comparison with human gingival fibroblasts (HGF) in culture. Northern blot analysis showed that mRNAs of interleukin 1beta (IL-1beta) and IL-8, but not IL-6, in HGEC were induced in response to A. actinomycetemcomitans. Secretion of IL-8 by HGEC was also increased following A. actinomycetemcomitans challenge, whereas production of IL-1beta could not be detected. The levels of IL-8 and its mRNA were increased depending on the concentration of A. actinomycetemcomitans. The co-culture with HGF and A. actinomycetemcomitans resulted in an increase in the levels of IL-6 and IL-8 mRNA in HGF. However, HGF exposed to A. actinomycetemcomitans, showed no expression of IL-1beta mRNA. These findings demonstrated that HGEC and HGF stimulated with A. actinomycetemcomitans have different profiles in cytokine mRNA expression. Furthermore, A. actinomycetemcomitans may play an important role in amplifying the local immune response and in initiating inflammatory reaction through release of IL-8 from gingival epithelial cells.
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Tsukube T, Ataka K, Sakata M, Wakita N, Okita Y. Surgical treatment of an aneurysm in the right aortic arch with aberrant left subclavian artery. Ann Thorac Surg 2001; 71:1710-1. [PMID: 11383841 DOI: 10.1016/s0003-4975(00)02698-9] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
A saccular aneurysm in the right-sided aortic arch with aberrant left subclavian artery is an uncommon disease, and surgical treatment is complicated. Three patients with Edwards type III-B right aortic arch and enlargement of the Kommerell's diverticulum underwent operations. Right thoracotomy was the preferred approach for this lesion and partial cardiopulmonary bypass is a safe and simple procedure when the aortic arch has mild atherosclerosis.
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Tsuruha J, Masuko-Hongo K, Kato T, Sakata M, Nakamura H, Nishioka K. Implication of cartilage intermediate layer protein in cartilage destruction in subsets of patients with osteoarthritis and rheumatoid arthritis. ARTHRITIS AND RHEUMATISM 2001; 44:838-45. [PMID: 11315923 DOI: 10.1002/1529-0131(200104)44:4<838::aid-anr140>3.0.co;2-c] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
OBJECTIVE To investigate whether cartilage intermediate layer protein (CILP), a protein recently cloned from human articular cartilage, is recognized as an autoantigen in patients with osteoarthritis (OA) and rheumatoid arthritis (RA), and whether the immune response against CILP is involved in disease pathogenesis. METHODS Recombinant fusion proteins, which contain the first half (C1), second half (C2), or 3 fragments within the C2 region (designated C2F1, C2F2, and C2F3) of the non-porcine nucleotide pyrophosphohydrolase-homologous region of CILP, were prepared using Escherichia coli. Autoantibodies to these proteins in serum samples from patients with OA or RA and from age-matched healthy individuals were detected by enzyme-linked immunosorbent assay and Western blotting. In addition, mice were immunized with a mixture of the C1 and C2 fusion proteins to assess the arthrogenicity of CILP. RESULTS Production of antibodies to the C2 region was detected in 10.5% (11 of 105) of the tested OA patients and in 8.0% (7 of 88) of the tested RA patients, although antibodies to the C1 region were rarely detected in either patient group. All C2F1, C2F2, and C2F3 fragments were found to carry autoepitopes. The C2F2 fusion protein was recognized most frequently in the tested OA patients, whereas the C2F3 fusion protein was dominantly recognized in the tested RA patients. All 4 mice strains, DBA/1J, ICR, C57BL/6, and BALB/c, immunized with the CILP fusion proteins developed chronic arthritis; in particular, the ICR mice developed polyarthritis that was characterized by infiltration of mononuclear cells in the synovium and exfoliation of the surface of cartilage. CONCLUSION The immune response to CILP may play a role in the pathogenesis of inflammatory joint destruction. Our results support the role of an immune-mediated process in the joint destruction present in chronic arthropathies such as OA and RA. The results suggest that suppression of immune responses to various components of the cartilage, such as CILP, might be therapeutically beneficial in these chronic arthropathies.
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109
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Minami H, Wakita N, Kawanishi Y, Kitano I, Sakata M. Impending rupture in an aortic arch aneurysm by Candida infection. THE JAPANESE JOURNAL OF THORACIC AND CARDIOVASCULAR SURGERY : OFFICIAL PUBLICATION OF THE JAPANESE ASSOCIATION FOR THORACIC SURGERY = NIHON KYOBU GEKA GAKKAI ZASSHI 2001; 49:178-80. [PMID: 11305059 DOI: 10.1007/bf02913598] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
A 68-year-old man was hospitalized with the complaints of left back pain and fever. He had a history of using steroids to treat uveitis for about thirty years. Computed tomography on the chest demonstrated an impending rupture in an aortic arch aneurysm, which was consequently surgically excised. Candida albicans was identified in the wall of the aneurysm, so fluconazole and itraconazole were administered. The patient was discharged at 120 days after surgery without recrudescence of the candida. To our knowledge, this is the fifteenth case of a successfully treated aneurysm caused by candida infection.
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110
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Gotoh M, Sakata M, Endo T, Hayashi H, Seno H, Suzuki O. Profenofos metabolites in human poisoning. Forensic Sci Int 2001; 116:221-6. [PMID: 11182275 DOI: 10.1016/s0379-0738(00)00377-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Profenofos and its metabolites were determined in a case of fatal poisoning. Little profenofos and large amounts of metabolites were detected by gas chromatography/flame photometric detection in the acid extracts of blood and urine after methylation with diazomethane. Four major metabolites containing phosphorus were identified with the synthesized metabolites, namely, despropylated profenofos, desethylated profenofos and des-S-propylated profenofos, respectively. 4-Bromo-2-chlorophenol (BCP), an aryl moiety of profenofos, was also determined in blood and urine with high performance liquid chromatograph (HPLC) as free or conjugated metabolites.
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111
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Sakata M, Matsubara F, Abe Y, Katsura S. Computer experiments for the glass-like phase of two-dimensional spin systems. ACTA ACUST UNITED AC 2001. [DOI: 10.1088/0022-3719/10/15/022] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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112
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Sakata M, Suzuki K, Koshiji T. Variations of wood delta(13)C for the past 50 years in declining Siebold's beech (Fagus crenata) forests. ENVIRONMENTAL AND EXPERIMENTAL BOTANY 2001; 45:33-41. [PMID: 11165629 DOI: 10.1016/s0098-8472(00)00074-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Markedly damaged stands have been observed in Siebold's beech (Fagus crenata) forests on the Tanzawa Mountains, Japan, which are located close to densely populated and heavily industrial areas. We measured the delta(13)C records for the past 50 years (1944-1997) in wood cellulose sampled from relatively healthy trees in declining forests on Mt. Hinokiboramaru (1600 m). This may provide information on the history of stresses related to environmental changes, which have caused the decline symptoms. The results showed that, for all of the trees studied, wood delta(13)C has decreased with time. Also, the difference in delta(13)C among trees grew abruptly after the mid-1960s, which almost coincides with the time when the decline symptoms were markedly observed. Some trees with large reduction of wood delta(13)C exhibited the strong decreases in radial growth. This suggests that the reduction of tree growth may have been more greatly influenced by decreasing carboxylation rate than by stomatal limitation. It is unlikely that water stress and SO(2) and O(3) stresses have induced the growth reduction, because those stresses cause increasing wood delta(13)C. This is supported by the facts that wet conditions and relatively low SO(2) and O(3) levels have been observed near Mt. Hinokiboramaru. In addition, analyses of wood Ca showed no evidence that acid fog and soil acidification have affected the wood delta(13)C and growth through effects on the nutrient uptake of trees. However, what type of stresses have induced the large reduction of wood delta(13)C and growth for some of the trees studied remains unknown because of the lack of sufficient data for evaluation. In contrast, lesser reduction of wood delta(13)C from the other trees may be related to an increase in the plant water-use efficiency with increasing atmospheric CO(2) concentration.
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113
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Sakata M, Cowlam N, Davies HA. Neutron diffraction measurement of the structure factor of a CuTi metallic glass. ACTA ACUST UNITED AC 2001. [DOI: 10.1088/0305-4608/9/12/001] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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115
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Morimoto Y, Sakata M, Ohno A, Maegawa T, Tajima S. [Effects of bofu-tsusho-san, a traditional Chinese medicine, on body fat accumulation in fructose-loaded rats]. Nihon Yakurigaku Zasshi 2001; 117:77-86. [PMID: 11233300 DOI: 10.1254/fpj.117.77] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The effects of Bofu-tsusho-san (BOF), a traditional Chinese medicine, on fructose-induced hypertriglyceridemia and body fat accumulation were investigated in female SD rats. Rats were allowed to drink ad libitum 25% (w/w) fructose solution for 6 weeks. BOF was administered to the rats as an experimental diet containing 1.5% or 4.5% (w/w) of BOF during the fructose-loading period. BOF suppressed body weight gain and prevented the elevation of serum triglyceride levels and body fat accumulation in fructose-loaded rats without affecting food and fructose intake. Furthermore, BOF prevented the increase of triglyceride content in the liver and the reduction of mitochondrial cytochome c oxidase activity in the brown adipose tissue induced by fructose. From these results, it has been suggested that BOF has a preventive effect against the body fat accumulation caused by excess intake of sugar or other fructose-containing foods. The inhibition of triglyceride synthesis in the liver, and the enhancement of lipolysis in adipocytes and of thermogenesis in brown adipose tissue have been presumed as the mechanisms of action of BOF.
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116
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Taneda S, Hayashi H, Sakata M, Yoshino S, Suzuki A, Sagai M, Mori Y. Anti-estrogenic activity of diesel exhaust particles. Biol Pharm Bull 2000; 23:1477-80. [PMID: 11145181 DOI: 10.1248/bpb.23.1477] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Estrogenic and anti-estrogenic activities of diesel exhaust particles (DEP) were evaluated using yeast cells expressing the human estrogen receptor and the responsive element regulating the expression of the receptor gene for beta-galactosidase (Routledge and Sumpter, 1996). It was found that a suspension of whole DEP suspension is not estrogenic but that this preparation possesses the ability to reduce the estrogen-dependent reporter activity. DEP were serially extracted with hexane, benzene, dichloromethane, methanol, and 1 M ammonia, and the estrogenic and anti-estrogenic activities of these preparations were determined. None of the extracts of DEP were estrogenic, but the extracts of benzene, dichloromethane and methanol possessed anti-estrogenic activity, and the activity of estrogen in the presence of hexane extract was slightly decreased. These results indicated that DEP contain heterologous compounds having anti-estrogenic activity. It is thought that those compounds in DEP can modulate the activity of estrogen, leading to the distruption of balance between estrogen and androgen. In this paper, the environmental effects of DEP in relation to the endocrine disrupting effect of organic compounds in DEP are discussed.
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Sakata M, Kobayashi H, Sun GW, Mochizuki O, Takagi A, Kojima T. Ryudocan expression by luteinized granulosa cells is associated with the process of follicle atresia. Fertil Steril 2000; 74:1208-14. [PMID: 11119752 DOI: 10.1016/s0015-0282(00)01587-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
OBJECTIVE To evaluate the presence of ryudocan in follicular fluid (FF) and its possible correlation with FF E(2) and P, and to study the levels of ryudocan in granulosa-lutein cells stimulated with hCG. DESIGN Controlled clinical study and in vitro experiment. SETTING University teaching hospital. PATIENT(S) One hundred seven patients undergoing IVF. INTERVENTION(S) The FF and granulosa-lutein cells were aspirated from follicles 34 hours after an ovulatory gonadotropin bolus. MAIN OUTCOME MEASURE(S) FF ryudocan, E(2), and P levels as well as hCG-mediated induction of ryudocan. RESULT(S) Ryudocan was abundant in the FF; the concentration of ryudocan in human FF was estimated to be 305.5 +/- 200.8 ng/mL (mean +/- SD). Atretic follicles had higher concentrations of ryudocan (559.1 +/- 156.5 ng/mL). FF ryudocan levels were inversely correlated with FF E(2) (r = -0.5023) and P concentrations (r = -0.4459). A detectable amount of ryudocan was found in pooled granulosa-lutein cells. Ryudocan production was augmented by surge levels of hCG. CONCLUSION(S) Ryudocan is expressed in luteinized granulosa cells in vitro. The higher concentrations of ryudocan in FF of atretic follicles suggest an involvement of ryudocan in the process of atresia.
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Sakata M, Cowlam N, Davies HA. Chemical short-range order in liquid and amorphous Cu66Ti34alloys. ACTA ACUST UNITED AC 2000. [DOI: 10.1088/0305-4608/11/7/005] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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119
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Takeda K, Sakui K, Sakata M. Temperature dependence of mobility and Hall coefficient factor for holes of highly pure silicon. ACTA ACUST UNITED AC 2000. [DOI: 10.1088/0022-3719/15/4/022] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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120
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Takeda K, Taguchi A, Sakata M. Valence-band parameters and hole mobility of Ge-Si alloys-theory. ACTA ACUST UNITED AC 2000. [DOI: 10.1088/0022-3719/16/12/013] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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121
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Takeda K, Sakui K, Taguchi A, Sakata M. Effect of intervalence-band interaction on relaxation time and transport coefficients for holes in non-polar semiconductors. ACTA ACUST UNITED AC 2000. [DOI: 10.1088/0022-3719/16/4/018] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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122
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Wang CR, Kai T, Tomiyama T, Yoshida T, Kobayashi Y, Nishibori E, Takata M, Sakata M, Shinohara H. C66 fullerene encaging a scandium dimer. Nature 2000; 408:426-7. [PMID: 11100714 DOI: 10.1038/35044195] [Citation(s) in RCA: 279] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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123
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Himi T, Sakata M, Shintani T, Mitsuzawa H, Kamagata M, Satoh J, Sugimoto H. Middle ear imaging using virtual endoscopy and its application in patients with ossicular chain anomaly. ORL J Otorhinolaryngol Relat Spec 2000; 62:316-20. [PMID: 11054015 DOI: 10.1159/000027776] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Virtual endoscopy (VE) is a recently developed technique to provide a realistic surface rendering of various organs, which can be applied to the use of three-dimensional (3D) studies of several lesions. However, its advantages in otological disease have not been well investigated. In this study, we evaluated the application of VE in patients with ossicular chain anomalies. Virtual middle ear endoscopy was a time-saving method, however, we needed the appropriate technical procedures of algorithm and reconstruction spacing to generate accurate 3D images of ossicles. We obtained virtual surgical views of middle ear structures and related anomalies, and confirmed by intraoperative findings that these images were mostly compatible with the actual lesions of ossicles. VE allowed an identification of the anatomy of the ossicles and adjacent structures simultaneously. The elements of the stapedial crura were clearly visualized with VE images in 93.3% of normal ears. Pathological ossicular chain findings such as malleus or incus fixation, dislocation and disruption, except footplate fixation were investigated successfully. One possible procedure, using alterable CT value in the obtained VE images on the monitor, is proposed for further detection of fine lesions of the ossicles. These observations suggest that virtual middle ear simulations accurately represent major intraoperative findings. This technique may have an important role in preoperative planning, surgical training, and/or postoperative evaluation in otology.
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Kirihara K, Nakata T, Takata M, Kubota Y, Nishibori E, Kimura K, Sakata M. Covalent bonds in AlMnSi icosahedral quasicrystalline approximant. PHYSICAL REVIEW LETTERS 2000; 85:3468-3471. [PMID: 11030923 DOI: 10.1103/physrevlett.85.3468] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2000] [Indexed: 05/23/2023]
Abstract
Electron density distributions were obtained using the maximum entropy method with synchrotron radiation powder data. In the metallic Al12Re, metallic bonding was observed for the icosahedral Al12 cluster with central Re atom. In the nonmetallic alpha-AlMnSi 1/1 approximant, covalent bonds were found in the electron density distribution of the Mackay icosahedral cluster without central atom. Rather than the Hume-Rothery mechanism, the covalency of Al (Si) icosahedron and that between Al (Si) and Mn atoms is considered to be the origin of the pseudogap and nonmetallic behavior of alpha-AlMnSi.
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Hino N, Ohtsuka K, Hashimoto M, Sakata M. Radiographic features of an aneurysmal bone cyst of the orbit. Ophthalmologica 2000; 212:198-201. [PMID: 9562098 DOI: 10.1159/000027278] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Aneurysmal bone cyst is an unusual benign solitary lesion of bone occurring rarely in the orbit. In this report, we present computed tomography and magnetic resonance images of an orbital aneurysmal bone cyst involving the frontal bone in a 16-month-old boy. The aneurysmal bone cyst exhibited bone destruction, new bone formation of the orbital roof and fluid-fluid levels in the lesion following hemorrhage. These radiographic features may be useful for diagnosing orbital aneurysmal bone cysts.
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