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Hiyama Y, Wada O, Nakakita S, Mizuno K. Joint awareness after total knee arthroplasty is affected by pain and quadriceps strength. Orthop Traumatol Surg Res 2016; 102:435-9. [PMID: 27052936 DOI: 10.1016/j.otsr.2016.02.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2015] [Revised: 02/11/2016] [Accepted: 02/24/2016] [Indexed: 02/02/2023]
Abstract
INTRODUCTION There is a growing interest in the use of patient-reported outcomes to provide a more patient-centered view on treatment. Forgetting the artificial joint can be regarded as the goal in joint arthroplasty. The goals of the study were to describe changes in joint awareness in the artificial joint after total knee arthroplasty (TKA), and to determine which factors among pain, knee range of motion (ROM), quadriceps strength, and functional ability affect joint awareness after TKA. HYPOTHESIS Patients undergoing TKA demonstrate changes in joint awareness and joint awareness is associated with pain, knee ROM, quadriceps strength, and functional ability. PATIENTS AND METHODS This prospective cohort study comprised 63 individuals undergoing TKA, evaluated at 1, 6, and 12 months postoperatively. Outcomes included joint awareness assessed using the Forgotten Joint Score (FJS), pain score, knee ROM, quadriceps strength, and functional ability. RESULTS Fifty-eight individuals completed all postoperative assessments. All measures except for knee extension ROM improved from 1 to 6 months. However, there were no differences in any measures from 6 to 12 months. FJS was affected most greatly by pain at 1 month and by quadriceps strength at 6 and 12 months. DISCUSSION Patients following TKA demonstrate improvements in joint awareness and function within 6 months after surgery, but reach a plateau from 6 to 12 months. Quadriceps strength could contribute to this plateau of joint awareness. LEVEL OF EVIDENCE Prospective cohort study, IV.
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Sato T, Takata T, Nebashi T, Murakawa S, Mizuno K, Akimoto N. 696 MEK and BRAF inhibitors augment the production and accumulation of sebum in hamster sebocytes. J Invest Dermatol 2016. [DOI: 10.1016/j.jid.2016.02.738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Okuyama K, Kawaguchi T, Shimura M, Noguchi K, Mizuno K, Bächinger HP. Crystal structure of the collagen model peptide (Pro-Pro-Gly)4-Hyp-Asp-Gly-(Pro-Pro-Gly)4 at 1.0 Å resolution. Biopolymers 2016; 99:436-47. [PMID: 23616212 DOI: 10.1002/bip.22198] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2012] [Revised: 12/20/2012] [Accepted: 12/26/2012] [Indexed: 11/11/2022]
Abstract
The single-crystal structure of the collagen-like peptide (Pro-Pro-Gly)4 -Hyp-Asp-Gly-(Pro-Pro-Gly)4, was analyzed at 1.02 Å resolution. The overall average helical twist (θ = 49.6°) suggests that this peptide adopts a 7/2 triple-helical structure and that its conformation is very similar to that of (Gly-Pro-Hyp)9, which has the typical repeating sequence in collagen. High-resolution studies on other collagen-like peptides have shown that imino acid-rich sequences preferentially adopt a 7/2 triple-helical structure (θ = 51.4°), whereas imino acid-lean sequences adopt relaxed conformations (θ < 51.4°). The guest Gly-Hyp-Asp sequence in the present peptide, however, has a large helical twist (θ = 61.1°), whereas that of the host Pro-Pro-Gly sequence is small (θ = 46.7°), indicating that the relationship between the helical conformation and the amino acid sequence of such peptides is complex. In the present structure, a strong intermolecular hydrogen bond between two Asp residues on the A and B strands might induce the large helical twist of the guest sequence; this is compensated by a reduced helical twist in the host, so that an overall 7/2-helical symmetry is maintained. The Asp residue in the C strand might interact electrostatically with the N-terminus of an adjacent molecule, causing axial displacement, reminiscent of the D-staggered structure in fibrous collagens.
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Matsuzawa Y, Kamezaki N, Ishihara T, Omuta K, Takeshita H, Goto K, Arata T, Honda H, Kameda K, Kashima Y, Kayo M, Kawazu I, Kodama J, Kumazawa Y, Kuroyanagi K, Mizobuchi K, Mizuno K, Oki K, Watanabe KK, Yamamoto A, Yamashita Y, Yamato T, Hamabata T, Ishizaki A, Dutton PH. Fine-scale genetic population structure of loggerhead turtles in the Northwest Pacific. ENDANGER SPECIES RES 2016. [DOI: 10.3354/esr00724] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Minami Y, Kajimoto K, Sato N, Aokage T, Mizuno M, Asai K, Munakata R, Yumino D, Murai K, Hagiwara N, Mizuno K, Kasanuki H, Takano T. Third heart sound in hospitalised patients with acute heart failure: insights from the ATTEND study. Int J Clin Pract 2015; 69:820-8. [PMID: 25521285 DOI: 10.1111/ijcp.12603] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Several previous studies have suggested that detection of a third heart sound (S3) in patients with chronic congestive heart failure is associated with adverse long-term outcomes. However, the short-term prognostic value of identifying an S3 on admission in patients with acute heart failure (AHF) is not well established. We therefore analysed the in-hospital prognostic value of detecting an S3 on admission in hospitalised patients with AHF. METHODS The Acute Decompensated Heart Failure Syndromes (ATTEND) study investigators enrolled 4107 patients hospitalised with AHF. Investigators evaluated the presence or absence of an S3 during routine physical examination. RESULTS On admission to hospital, 1673 patients (41%) had an S3. Patients with an S3 had a higher heart rate, higher serum level of B-type natriuretic peptide and higher creatinine levels than patients without an S3. However, there were no significant differences of systolic blood pressure, serum sodium, haemoglobin, C-reactive protein and total bilirubin between the two groups. Multivariate analysis adjusted for various markers of disease severity revealed that only the presence of an S3 was independently associated with an increase of in-hospital all cause death [adjusted odds ratio (OR), 1.69; 95% confidence interval (CI), 1.19-2.41; p = 0.003] and cardiac death (adjusted OR, 1.66; 95% CI, 1.08-2.54; p = 0.020) among the congestive physical findings related to heart failure (S3, rales, jugular venous distension and peripheral oedema). CONCLUSIONS Detecting an S3 on admission was independently associated with adverse in-hospital outcomes in patients with AHF. Our findings suggest that careful bedside assessment is clinically meaningful.
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Sato H, Hasegawa G, Takeuchi M, Takahashi K, Sato Y, Hashimoto S, Mizuno K, Kobayashi M. Education and Imaging. Gastroenterology: A unique endoscopic technique for full-layer histology of jackhammer esophagus. J Gastroenterol Hepatol 2015. [PMID: 26201667 DOI: 10.1111/jgh.12914] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
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Takahashi K, Sato H, Sato Y, Takeuchi M, Takeda SR, Mizuno K, Hashimoto S, Hasegawa G, Kobayashi M. Education and Imaging. Gastroenterology: Histopathological investigation of distal esophageal spasm (DES) using per-oral endoscopic myotomy (POEM). J Gastroenterol Hepatol 2015; 30:1113. [PMID: 26094661 DOI: 10.1111/jgh.12926] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Takahashi Y, Fujiwara T, Yamaguchi T, Kawakami M, Mizuno K, Tsuji T, Liu M. The effect of patterned electrical stimulation combined with voluntary contraction on spinal reciprocal inhibition. Physiotherapy 2015. [DOI: 10.1016/j.physio.2015.03.1443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Terao K, Kanenaga R, Yoshida T, Mizuno K, Bächinger HP. Temperature induced complex formation-deformation behavior of collagen model peptides and polyelectrolytes in aqueous solution. POLYMER 2015. [DOI: 10.1016/j.polymer.2015.03.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Moriuchi S, Yoshizawa S, Mizuno K, Hosoya N, Noda S, Kubota K. Effect of 1,25-dihydroxycholecalciferol on the duodenal villi and alkaline phosphatase in the developing chick embryo. CONTRIBUTIONS TO NEPHROLOGY 2015; 22:9-17. [PMID: 6893176 DOI: 10.1159/000385982] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Administration of 1,25-(OH)2D3 to developing 14-day chick embryo gave precocious induction of alkaline phosphatase in 20-day chick embryonic duodenum. 1,25-(OH)-2D3-induced alkaline phosphase involved in changes in Km and Vmax values. Furthermore, polyacrylamide gel disc electrophoresis of n-butanol-solubilized alkaline phosphatase from control and 1,25-(OH)2D3-treated chick embryonic duodenum revealed that 1,25-(OH)2D3 involved the transformation of neuraminidase-resistant fast migrating form to the neuraminidase-sensitive faster migrating one. Scanning electron microscopic data showed that the injection of 1,25-(OH)2D3 stimulated the elongation of duodenal microvilli, although there was no effect on the duodenal absorptive epithelial cell height.
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Terao K, Mizuno K, Bächinger HP. Conformational change from rigid rod to star: a triple-helical peptide with a linker domain at the C-terminal end. J Phys Chem B 2015; 119:3714-9. [PMID: 25685884 DOI: 10.1021/jp5129172] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Small-angle X-ray scattering and circular dichroism measurements were made for a triple-helical peptide of which one end was linked by the thermally stable trimerization domain of type XIX collagen. The radius of gyration decreased steeply around the transition temperature while the scattering intensity at zero angle did not significantly change, indicating no molar mass change through the conformational transition. Thus, the data were analyzed in terms of the rigid cylinder model for the data at low temperatures and the wormlike star model at high temperatures. It was confirmed that the peptide molecules behave as a rod-like cylinder at low temperature and a semi flexible three-arm star-like chain at high temperature of which the single-coil peptide chain is appreciably extended by the high segment density nearby the linking domain.
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Saito T, Asai K, Sato S, Takano H, Mizuno K, Shimizu W. Ultrastructural features of cardiomyocytes in dilated cardiomyopathy with initially decompensated heart failure as a predictor of prognosis. Eur Heart J 2014; 36:724-32. [DOI: 10.1093/eurheartj/ehu404] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Easton AC, Lourdusamy A, Havranek M, Mizuno K, Solati J, Golub Y, Clarke TK, Vallada H, Laranjeira R, Desrivières S, Moll GH, Mössner R, Kornhuber J, Schumann G, Giese KP, Fernandes C, Quednow BB, Müller CP. αCaMKII controls the establishment of cocaine's reinforcing effects in mice and humans. Transl Psychiatry 2014; 4:e457. [PMID: 25290264 PMCID: PMC4350526 DOI: 10.1038/tp.2014.97] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Revised: 07/18/2014] [Accepted: 08/21/2014] [Indexed: 12/23/2022] Open
Abstract
Although addiction develops in a considerable number of regular cocaine users, molecular risk factors for cocaine dependence are still unknown. It was proposed that establishing drug use and memory formation might share molecular and anatomical pathways. Alpha-Ca(2+)/calmodulin-dependent protein kinase-II (αCaMKII) is a key mediator of learning and memory also involved in drug-related plasticity. The autophosphorylation of αCaMKII was shown to accelerate learning. Thus, we investigated the role of αCaMKII autophosphorylation in the time course of establishing cocaine use-related behavior in mice. We found that αCaMKII autophosphorylation-deficient αCaMKII(T286A) mice show delayed establishment of conditioned place preference, but no changes in acute behavioral activation, sensitization or conditioned hyperlocomotion to cocaine (20 mg kg(-1), intraperitoneal). In vivo microdialysis revealed that αCaMKII(T286A) mice have blunted dopamine (DA) and blocked serotonin (5-HT) responses in the nucleus accumbens (NAcc) and prefrontal cortex after acute cocaine administration (20 mg kg(-1), intraperitoneal), whereas noradrenaline responses were preserved. Under cocaine, the attenuated DA and 5-HT activation in αCaMKII(T286A) mice was followed by impaired c-Fos activation in the NAcc. To translate the rodent findings to human conditions, several CAMK2A gene polymorphisms were tested regarding their risk for a fast establishment of cocaine dependence in two independent samples of regular cocaine users from Brazil (n=688) and Switzerland (n=141). A meta-analysis across both samples confirmed that CAMK2A rs3776823 TT-allele carriers display a faster transition to severe cocaine use than C-allele carriers. Together, these data suggest that αCaMKII controls the speed for the establishment of cocaine's reinforcing effects.
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Mizuno K, Kurokawa K, Ohkuma S. SY23-1 * BASIC RESEARCH OF ALCOHOL DEPENDENCE. Alcohol Alcohol 2014. [DOI: 10.1093/alcalc/agu052.99] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Ide K, Yamada H, Umegaki K, Mizuno K, Kawakami N, Hagiwara Y, Matsumoto M, Yoshida H, Kim K, Shiosaki E, Yokochi T, Harada K. PP273-MON: Outstanding abstract: Lymphocyte and Plasma Vitamin Levels as Potential Biomarkers for Parkinson’s Disease Progression. Clin Nutr 2014. [DOI: 10.1016/s0261-5614(14)50607-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Fukami Y, Kurumiya Y, Mizuno K, Sekoguchi E, Kobayashi S. Clinical effect of hyperbaric oxygen therapy in adhesive postoperative small bowel obstruction. Br J Surg 2014; 101:433-7. [PMID: 24496799 DOI: 10.1002/bjs.9389] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/29/2013] [Indexed: 11/09/2022]
Abstract
BACKGROUND Hyperbaric oxygen (HBO) therapy is a controversial treatment for adhesive postoperative small bowel obstruction, with only a few small studies reported. The aim of this study was to assess the clinical value of HBO therapy in the treatment of adhesive postoperative small bowel obstruction. METHODS Between April 2006 and March 2012, all patients with adhesive postoperative small bowel obstruction were treated using either decompression therapy or HBO. Patients undergoing HBO therapy were treated once a day at a pressure of 2·0 atmospheres absolute and received 100 per cent oxygen. Patients showing no clinical and radiological improvement with HBO therapy were converted to decompression therapy by means of a long tube. Medical records were reviewed and outcomes analysed. RESULTS A total of 305 patients were treated, of whom 142 underwent tube decompression therapy during the first 3 years and the remaining 163 had HBO therapy during the last 3 years. The median number of HBO treatments was 3 (range 1-7). A total of 143 patients (87·7 per cent) were treated successfully with HBO without long-tube decompression. HBO therapy was associated with earlier resumption of oral intake (mean 4·7 versus 6·5 days; P = 0·001) and a shorter hospital stay (mean 10·3 versus 14·1 days; P = 0·001). The rate of operation was 7·4 per cent in the HBO group and 14·8 per cent in group treated by decompression alone (P = 0·037). CONCLUSION In this study, HBO therapy was safe for the treatment of adhesive postoperative small bowel obstruction. It reduced the need for surgery and time to recovery as well as the hospital stay.
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Fukami Y, Kurumiya Y, Mizuno K, Sekoguchi E, Kobayashi S. Clinical effect of hyperbaric oxygen therapy in adhesive postoperative small bowel obstruction. THE BRITISH JOURNAL OF SURGERY 2014. [PMID: 24496799 DOI: 10.1002/bjs.9389p] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
BACKGROUND Hyperbaric oxygen (HBO) therapy is a controversial treatment for adhesive postoperative small bowel obstruction, with only a few small studies reported. The aim of this study was to assess the clinical value of HBO therapy in the treatment of adhesive postoperative small bowel obstruction. METHODS Between April 2006 and March 2012, all patients with adhesive postoperative small bowel obstruction were treated using either decompression therapy or HBO. Patients undergoing HBO therapy were treated once a day at a pressure of 2·0 atmospheres absolute and received 100 per cent oxygen. Patients showing no clinical and radiological improvement with HBO therapy were converted to decompression therapy by means of a long tube. Medical records were reviewed and outcomes analysed. RESULTS A total of 305 patients were treated, of whom 142 underwent tube decompression therapy during the first 3 years and the remaining 163 had HBO therapy during the last 3 years. The median number of HBO treatments was 3 (range 1-7). A total of 143 patients (87·7 per cent) were treated successfully with HBO without long-tube decompression. HBO therapy was associated with earlier resumption of oral intake (mean 4·7 versus 6·5 days; P = 0·001) and a shorter hospital stay (mean 10·3 versus 14·1 days; P = 0·001). The rate of operation was 7·4 per cent in the HBO group and 14·8 per cent in group treated by decompression alone (P = 0·037). CONCLUSION In this study, HBO therapy was safe for the treatment of adhesive postoperative small bowel obstruction. It reduced the need for surgery and time to recovery as well as the hospital stay.
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Kamiya M, Asai K, Noma S, Komiyama H, Shirakabe A, Sato N, Mizuno K. Beta-3 adrenergic receptor agonist prevents diastolic dysfunction in angiotensin2-induced cardiomyopathy mouse model. Eur Heart J 2013. [DOI: 10.1093/eurheartj/eht309.p3332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Murata H, Miyauchi Y, Katoh T, Ueno A, Yodogawa K, Iwasaki Y, Hayashi M, Tanaka K, Simizu W, Mizuno K. Clinical and electrophysiological characteristics of electrical storm of monomorphic ventricular tachycardia refractory to intravenous amiodarone. Eur Heart J 2013. [DOI: 10.1093/eurheartj/eht308.p1345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Miyazaki H, Miyanaga S, Shibayama K, Nakajima M, Ashikaga K, Nakano E, Sasaki T, Mizuno K, Harada T, Miyake F. Beneficial effect of alternative site pacing from right atrial mid-septum in patients with bradycardia-tachycardia syndrome. Eur Heart J 2013. [DOI: 10.1093/eurheartj/eht309.2621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Miyazaki H, Nakajima M, Ashikaga K, Nakano E, Sasaki T, Mizuno K, Harada T, Miyake F. Adenosine-sensitive reentrant atrial tachycardia arising from atrioventricular annulus and atrial septum. Eur Heart J 2013. [DOI: 10.1093/eurheartj/eht307.p556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Setsuta K, Nishizawa A, Kitahara Y, Seino Y, Mizuno K. Heart-type fatty acid-binding protein is a novel prognostic marker in patients with essential hypertension. Eur Heart J 2013. [DOI: 10.1093/eurheartj/eht308.p2373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Mizuno K, Kurokawa K, Ohkuma S. Regulation of type 1 IP3 receptor expression by dopamine D2-like receptors via AP-1 and NFATc4 activation. Neuropharmacology 2013; 71:264-72. [DOI: 10.1016/j.neuropharm.2013.03.036] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Revised: 03/27/2013] [Accepted: 03/29/2013] [Indexed: 10/27/2022]
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Pokidysheva E, Zientek KD, Ishikawa Y, Mizuno K, Vranka JA, Montgomery NT, Keene DR, Kawaguchi T, Okuyama K, Bächinger HP. Posttranslational modifications in type I collagen from different tissues extracted from wild type and prolyl 3-hydroxylase 1 null mice. J Biol Chem 2013; 288:24742-52. [PMID: 23861401 DOI: 10.1074/jbc.m113.464156] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Type I collagen extracted from tendon, skin, and bone of wild type and prolyl 3-hydroxylase 1 (P3H1) null mice shows distinct patterns of 3-hydroxylation and glycosylation of hydroxylysine residues. The A1 site (Pro-986) in the α1-chain of type I collagen is almost completely 3-hydroxylated in every tissue of the wild type mice. In contrast, no 3-hydroxylation of this proline residue was found in P3H1 null mice. Partial 3-hydroxylation of the A3 site (Pro-707) was present in tendon and bone, but absent in skin in both α-chains of the wild type animals. Type I collagen extracted from bone of P3H1 null mice shows a large reduction in 3-hydroxylation of the A3 site in both α-chains, whereas type I collagen extracted from tendon of P3H1 null mice shows little difference as compared with wild type. These results demonstrate that the A1 site in type I collagen is exclusively 3-hydroxylated by P3H1, and presumably, this enzyme is required for the 3-hydroxylation of the A3 site of both α-chains in bone but not in tendon. The increase in glycosylation of hydroxylysine in P3H1 null mice in bone was found to be due to an increased occupancy of normally glycosylated sites. Despite the severe disorganization of collagen fibrils in adult tissues, the D-period of the fibrils is unchanged. Tendon fibrils of newborn P3H1 null mice are well organized with only a slight increase in diameter. The absence of 3-hydroxyproline and/or the increased glycosylation of hydroxylysine in type I collagen disturbs the lateral growth of the fibrils.
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