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Ishii K, Shibataf A, Oka K. Recess physical activity and perceived school environment among elementary school children. J Sci Med Sport 2014. [DOI: 10.1016/j.jsams.2014.11.360] [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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Oka K, Ishii K, Shibata A. Descriptive epidemiology of objectively measured sedentary time among Japanese adults. J Sci Med Sport 2014. [DOI: 10.1016/j.jsams.2014.11.379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Utsuno H, Miyamoto T, Oka K, Shiozawa T. Morphological alterations in protamine-deficient spermatozoa. Hum Reprod 2014; 29:2374-81. [DOI: 10.1093/humrep/deu225] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
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Lai WF, Oka K, Jung HS. Advanced functional polymers for regenerative and therapeutic dentistry. Oral Dis 2014; 21:550-7. [PMID: 25098817 DOI: 10.1111/odi.12281] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Revised: 06/23/2014] [Accepted: 08/01/2014] [Indexed: 01/16/2023]
Abstract
Use of ceramics and polymers continues to dominate clinical procedures in modern dentistry. Polymers have provided the basis for adhesives, tissue void fillers, and artificial replacements for whole teeth. They have been remarkably effective in the clinic at restoration of major dental functions after damage or loss of teeth. With the rapid development of polymer science, dental materials science has significantly lagged behind in harnessing these advanced polymer products. What they offer is new and unique properties superior to traditional polymers and crucially a range of properties that more closely match natural biomaterials. Therefore, we should pursue more vigorously the benefits of advanced polymers in dentistry. In this review, we highlight how the latest generation of advanced polymers will enhance the application of materials in the dental clinic using numerous promising examples. Polymers have a broad range of applications in modern dentistry. Some major applications are to construct frameworks that mimic the precise structure of tissues, to restore tooth organ function, and to deliver bioactive agents to influence cell behavior from the inside. The future of polymers in dentistry must include all these new enhancements to increase biological and clinical effectiveness beyond what can be achieved with traditional biomaterials.
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Murase T, Takeyasu Y, Oka K, Kataoka T, Tanaka H, Yoshikawa H. Three-Dimensional Corrective Osteotomy for Cubitus Varus Deformity with Use of Custom-Made Surgical Guides. JBJS Essent Surg Tech 2014. [DOI: 10.2106/jbjs.st.m.00044.test] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Shimoi T, Mizutani K, Kojima D, Kitamura Y, Hotta K, Ogawa H, Oka K. Identification of oscillatory firing neurons associated with locomotion in the earthworm through synapse imaging. Neuroscience 2014; 268:149-58. [PMID: 24657777 DOI: 10.1016/j.neuroscience.2014.03.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Revised: 03/06/2014] [Accepted: 03/10/2014] [Indexed: 11/16/2022]
Abstract
We used FM imaging to identify neurons that receive sensory feedback from the body wall in a circuit for octopamine (OA)-evoked rhythmic locomotion in the earthworm, Eisenia fetida. We visualized synapses in which postsynaptic neurons receive the sensory feedback, by using FM1-43 dye to label the synapses of both motor and sensory pathways that are associated with locomotion, then clearing the motor pathway synapse labeling, and finally identifying the target synapses by distinguishing physiologically functional synapses through destaining using a high-K(+) solution. A pair of synaptic regions associated with the sensory feedback was found to be located two or three cell body-widths away from the midline, between the anterior parts of the roots of the second lateral nerves (LNs) at the segmental ganglia (SGs). Using conventional intracellular recording and dye loading of the cell bodies surrounding these synaptic regions, we identified a pair of bilateral neurons with cell bodies larger than those of other cells in these regions, and named them "Oscillatory firing neurons Projecting to Peripheral nerves" (OPPs). These had a bipolar shape and projected neurites to the ipsilateral first and third LNs, fired rhythmically, and had a burst timing synchronized with the motor pattern bursts from the ipsilateral first LNs. Current injection into an OPP caused firing in the ipsilateral first LNs, supporting the hypothesis that OPPs functionally project to the peripheral nerves. OPPs also sent neurites to the adjacent anterior and posterior SGs, suggesting connections with the adjacent segments. We conclude that FM imaging can be used to identify neurons involved in specific functions, and that OPPs are the first neurons to be associated with OA-induced locomotion in the earthworm.
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Miyake J, Shimada K, Oka K, Tanaka H, Sugamoto K, Yoshikawa H, Murase T. Arthroscopic debridement in the treatment of patients with osteoarthritis of the elbow, based on computer simulation. Bone Joint J 2014; 96-B:237-41. [DOI: 10.1302/0301-620x.96b2.30714] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
We retrospectively assessed the value of identifying impinging osteophytes using dynamic computer simulation of CT scans of the elbow in assisting their arthroscopic removal in patients with osteoarthritis of the elbow. A total of 20 patients were treated (19 men and one woman, mean age 38 years (19 to 55)) and followed for a mean of 25 months (24 to 29). We located the impinging osteophytes dynamically using computerised three-dimensional models of the elbow based on CT data in three positions of flexion of the elbow. These were then removed arthroscopically and a capsular release was performed. The mean loss of extension improved from 23° (10° to 45°) pre-operatively to 9° (0° to 25°) post-operatively, and the mean flexion improved from 121° (80° to 140°) pre-operatively to 130° (110° to 145°) post-operatively. The mean Mayo Elbow Performance Score improved from 62 (30 to 85) to 95 (70 to 100) post-operatively. All patients had pain in the elbow pre-operatively which disappeared or decreased post-operatively. According to their Mayo scores, 14 patients had an excellent clinical outcome and six a good outcome; 15 were very satisfied and five were satisfied with their post-operative outcome. We recommend this technique in the surgical management of patients with osteoarthritis of the elbow. Cite this article: Bone Joint J 2014;96-B:237–41.
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Ishii K, Shibata A, Oka K. Recommended physical activity and depression in Japanese adults. J Sci Med Sport 2012. [DOI: 10.1016/j.jsams.2012.11.053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Liao Y, Harada K, Shibata A, Ishii K, Oka K, Nakamura Y, Inoue S, Shimomitsu T. Association of self-reported physical activity patterns and socio-demographic factors among normal-weight and overweight Japanese men. J Sci Med Sport 2012. [DOI: 10.1016/j.jsams.2012.11.689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Shibata A, Ishii K, Oka K. Built environment and dog walking behavior among Japanese dog owners. J Sci Med Sport 2012. [DOI: 10.1016/j.jsams.2012.11.650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Harada K, Shibata A, Oka K, Nakamura Y. Prevalence and sociodemographic correlates of muscle-strengthening activity among Japanese older adults. J Sci Med Sport 2012. [DOI: 10.1016/j.jsams.2012.11.109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Onda K, Suzuki R, Tanaka S, Oga H, Oka K, Hirano T. Decitabine, a DNA methyltransferase inhibitor, reduces P-glycoprotein mRNA and protein expressions and increases drug sensitivity in drug-resistant MOLT4 and Jurkat cell lines. Anticancer Res 2012; 32:4439-4444. [PMID: 23060570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Multidrug resistance (MDR) is a major clinical obstacle in the treatment of several cancers including hematological malignancies and solid tumors. The ATP-binding cassette transporter B1 (ABCB1) gene and its product, P-glycoprotein (P-gp), is one molecule that is involved in drug resistance. Here we report on the effect of decitabine (5-aza-2'-deoxycytidine), an inhibitor of DNA methyltransferase, on ABCB1 mRNA and P-gp expressions in drug-resistant MOLT4 and Jurkat cells. We found that decitabine treatment reduced ABCB1 mRNA and P-gp expressions in MOLT4/daunorubicin-resistant and Jurkat/doxorubicin-resistant cells. The decrease in the expression of ABCB1 mRNA and P-gp was accompanied by increased sensitivity to anticancer drugs in both drug-resistant cell lines. Our data suggest that DNA methylation is one of the mechanisms underlying ABCB1/P-gp overexpression in drug-resistant hematopoietic cell lines. The modulation of ABCB1/P-gp by DNA methylation inhibitors may be an effective strategy to overcome P-gp-related drug resistance.
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Tatebe S, Oka K, Kuraoka S. Intramural bronchogenic cyst of the oesophagus. J Surg Case Rep 2012; 2012:3. [PMID: 24960743 PMCID: PMC3649661 DOI: 10.1093/jscr/2012.10.3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Bronchogenic cysts are relatively common mediastinal cysts. Here, we report removal of a rare paraoesophageal-type bronchogenic cyst by video-assisted thoracoscopic surgery in a 52-year-old male patient. The defect of the oesophageal wall was successfully reinforced with an intercostal muscle flap.
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Kuzian RO, Nishimoto S, Drechsler SL, Málek J, Johnston S, van den Brink J, Schmitt M, Rosner H, Matsuda M, Oka K, Yamaguchi H, Ito T. Ca(2)Y(2)Cu(5)O(10): the first frustrated quasi-1D ferromagnet close to criticality. PHYSICAL REVIEW LETTERS 2012; 109:117207. [PMID: 23005673 DOI: 10.1103/physrevlett.109.117207] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Revised: 07/05/2012] [Indexed: 06/01/2023]
Abstract
Ca(2)Y(2)Cu(5)O(10) is built up from edge-shared CuO(4) plaquettes forming spin chains. From inelastic neutron scattering data we extract an in-chain nearest-neighbor exchange J(1)≈-170 K and the frustrating next-neighbor J(2)≈32 K interactions, both significantly larger than previous estimates. The ratio α=|J(2)/J(1)|=0.19±0.01 places the system close to the critical point α(c)=0.25 of the J(1)-J(2) chain but in the 1D ferromagnetic regime. We establish that the vicinity to criticality only marginally affects the dispersion and coherence of the spin-wave-like magnetic excitations but instead results in a dramatic T dependence of high-energy Zhang-Rice singlet excitation intensities.
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Poungvarin N, Lee JK, Yechoor VK, Li MV, Assavapokee T, Suksaranjit P, Thepsongwajja JJ, Saha PK, Oka K, Chan L. Carbohydrate response element-binding protein (ChREBP) plays a pivotal role in beta cell glucotoxicity. Diabetologia 2012; 55:1783-96. [PMID: 22382520 PMCID: PMC4010252 DOI: 10.1007/s00125-012-2506-4] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2011] [Accepted: 01/10/2012] [Indexed: 01/09/2023]
Abstract
AIMS/HYPOTHESIS This study was aimed at the elucidation of the pathogenesis of glucotoxicity, i.e. the mechanism whereby hyperglycaemia damages pancreatic beta cells. The identification of pathways in the process may help identify targets for beta cell-protective therapy. Carbohydrate response element-binding protein (ChREBP), a transcription factor that regulates the expression of multiple hyperglycaemia-induced genes, is produced in abundance in pancreatic beta cells. We hypothesise that ChREBP plays a pivotal role in mediating beta cell glucotoxicity. METHODS We assessed the role of ChREBP in glucotoxicity in 832/13 beta cells, isolated mouse islets and human pancreas tissue sections using multiple complementary approaches under control and high-glucose-challenge conditions as well as in adeno-associated virus-induced beta cell-specific overexpression of Chrebp (also known as Mlxipl) in mice. RESULTS Under both in vitro and in vivo conditions, ChREBP activates downstream target genes, including fatty acid synthase and thioredoxin-interacting protein, leading to lipid accumulation, increased oxidative stress, reduced insulin gene transcription/secretion and enhanced caspase activity and apoptosis, processes that collectively define glucotoxicity. Immunoreactive ChREBP is enriched in the nucleuses of beta cells in pancreatic tissue sections from diabetic individuals compared with non-diabetic individuals. Finally, we demonstrate that induced beta cell-specific Chrebp overexpression is sufficient to phenocopy the glucotoxicity manifestations of hyperglycaemia in mice in vivo. CONCLUSIONS/INTERPRETATION These data indicate that ChREBP is a key transcription factor that mediates many of the hyperglycaemia-induced activations in a gene expression programme that underlies beta cell glucotoxicity at the molecular, cellular and whole animal levels.
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Ohno A, Oka K, Sakuma C, Okuda H, Fukuhara K. Characterization of tea cultivated at four different altitudes using 1H NMR analysis coupled with multivariate statistics. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2011; 59:5181-5187. [PMID: 21456619 DOI: 10.1021/jf200204y] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The taste of black tea differs according to the different areas in which the tea is grown, even for the same species of tea. A combination of (1)H NMR spectroscopy and partial least-squares discriminate analysis (PLS-DA) was used to assess the quality differences of tea leaves from four cultivation areas with different elevations, RAN > 1800 m, UDA = 1200 m, MEDA = 600 m, and YATA < 300 m, in Sri Lanka. As a result of a statistical analysis, PLS-DA showed a separation between high- and low-quality black teas derived from the four different tea cultivation areas. RAN from the highest elevation showed characteristic trends in the levels of theaflavin and theaflavin 3,3'-digallate that were found only in RAN, and the levels of theanine and caffeine were higher, and the levels of thearubigins, especially thearubigin 3,3'-digallate, were lower in RAN than in UDA, MEDA, and YATA. The structures of these components were determined by 1D and 2D NMR analyses. These results demonstrate that this method can be used to evaluate black tea quality according to the chemical composition or metabolites, which are characteristic of the tea leaves cultivated in four regions with different elevations in Sri Lanka.
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Toki K, Kyo M, Takahara S, Hatori M, Morozumi K, Ichimaru N, Tanaka T, Wang JD, Permpongkosol S, Miyamoto M, Oka K, Imai E, Kyakuno M, Nakamura T, Kojima Y, Inoue T, Kameoka H, Ding XQ, Kokado Y, Okuyama A. Clinocopathological evaluation in non-episode biopsies of renal transplant allograft. Transpl Int 2011. [DOI: 10.1111/j.1432-2277.2000.tb02121.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Ishii K, Shibata A, Oka K. Environmental, psychological, and social influences on physical activity among Japanese adults: A structural equation modelling. J Sci Med Sport 2010. [DOI: 10.1016/j.jsams.2010.10.660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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44
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Oka K, Ishii K, Shibata A. Determinants of physical activity among Japanese adults: A structural equation modelling. J Sci Med Sport 2010. [DOI: 10.1016/j.jsams.2010.10.663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Shibata A, Ishii K, Oka K. Awareness and belief about the role of physical activity in colorectal cancer prevention among Japanese adults. J Sci Med Sport 2010. [DOI: 10.1016/j.jsams.2010.10.669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Plumb NC, Reber TJ, Koralek JD, Sun Z, Douglas JF, Aiura Y, Oka K, Eisaki H, Dessau DS. Low-energy (<10 meV) feature in the nodal electron self-energy and strong temperature dependence of the Fermi velocity in Bi{2}Sr{2}CaCu{2}O{8+δ}. PHYSICAL REVIEW LETTERS 2010; 105:046402. [PMID: 20867869 DOI: 10.1103/physrevlett.105.046402] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2010] [Indexed: 05/29/2023]
Abstract
Using low photon energy angle-resolved photoemission, we study the low-energy dispersion along the nodal (π,π) direction in Bi{2}Sr{2}CaCu{2}O{8+δ} as a function of temperature. Less than 10 meV below the Fermi energy, the high-resolution data reveal a novel "kinklike" feature in the electron self-energy that is distinct from the larger well-known kink roughly 70 meV below E{F}. This new kink is strongest below the superconducting critical temperature and weakens substantially at higher temperatures. A corollary of this finding is that the Fermi velocity v{F}, as measured in this low-energy range, varies rapidly with temperature-increasing by almost 30% from 70 to 110 K. The behavior of v{F}(T) appears to shift as a function of doping, suggesting a departure from simple "universality" in the nodal Fermi velocity of cuprates.
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Matsuoka T, Kobayashi S, Oka K, Sakano H, Kawano K, Katoh T. [Thymic cancer with superior vena cava invasion reconstructed by ready-made Y-graft]. KYOBU GEKA. THE JAPANESE JOURNAL OF THORACIC SURGERY 2010; 63:379-381. [PMID: 20446606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
A 57-year-old woman was admitted to our hospital with a complaint of left supraclavicular lymph node's swelling in January 2007. Computed tomography (CT) showed the lobulated tumor suspected of superior vena cava (SVC) invasion, located in the anterior mediastinum, 5 x 3 cm in size. The patient underwent thymectomy, resection of SVC, and partial resection of the right upper lobe. SVC was reconstructed by ready-made Y-graft (Hemashied phi 18 x 9 mm). Histopathological diagnosis was thymic cancer, poorly differentiated squamous cell carcinoma. The patient was discharged on 21st postoperative day. Postoperative radiotherapy (RT : 12.6 Gy) was canceled for the side effect. Alternatively, adjuvant chemotherapy [carboplatin (CBDCA) +paclitaxel (PTX)] was administered. Additional RT (50 Gy) was given to the lesion of local recurrence 1 and half year after the operation. The patient was alive without any signs of recurrence after RT. Left side bypass graft was patent at 8 months postoperatively, but was obliterated thereafter. Right side bypass is patent at more than 2 years postoperatively. Ready-made Y-graft can be one of the choices of SVC reconstruction.
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Oka K, Namba Y, Ichimaru N, Moriyama T, Kyo M, Kokado Y, Imai E, Takahara S. Clinicopathological study of expression of lymphatic vessels in renal allograft biopsy after treatment for acute rejection. Transplant Proc 2010; 41:4154-8. [PMID: 20005358 DOI: 10.1016/j.transproceed.2009.09.067] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2008] [Revised: 03/10/2009] [Accepted: 09/15/2009] [Indexed: 10/20/2022]
Abstract
BACKGROUND Lymph vessel expression is related to inflammatory cell infiltration, around renal tubules in acute rejection episodes (ARE) of transplanted kidneys. However, there is little information on the lymph vessels after treatment of an ARE, particularly in relation to renal function and histological findings. PATIENTS AND METHODS We investigated 13 cases of ARE diagnosed by kidney transplant biopsy performed from 1997 to 2005 within 3 years of transplantation. Treatment of the ARE lead to an improved serum creatinine level in all cases. There was neither an ABO-incompatible nor an acute humoral rejection case. Lymphatic vessels in re-biopsies were examined using immunohistochemical staining with D2-40 antibody that detected lymphatic endothelium. Re-biopsy cases in which the baseline creatinine had increased by more than 20% despite treatment were considered the severe group; the others, as the stable group. The relation between lymphatic vessel density (LVD) and renal function was examined using Banff scores. RESULTS LVD was significantly higher in the severe than the stable group. The expression of lymph vessels versus the Banff score showed a direct relation: greater Banff scores showed higher expressions of lymph vessels. CONCLUSIONS The expression of lymph vessels in renal allograft specimens after treatment of an ARE was related to deterioration of renal function and inflammatory cell invasion. We plan a further examination of the relationship between the expression of lymph vessels and long-term prognosis.
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Tsujimoto K, Sakuma C, Uozaki M, Yamasaki H, Utsunomiya H, Oka K, Koyama AH. Antiviral effect of pyridinium formate, a novel component of coffee extracts. Int J Mol Med 2010; 25:459-63. [PMID: 20127052 DOI: 10.3892/ijmm_00000365] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
N-methyl-pyridinium formate, a novel component of coffee extracts, inhibited the multiplication of both DNA and RNA viruses. In the presence of the compound, the progeny viral yields of both herpes simplex virus type 1 (HSV-1) and poliovirus in HEp-2 cells and those of influenza virus type A in MDCK cells decreased with increasing concentrations of the compound, although the degree of viral sensitivity to this compound differed. In addition, none of these viruses were directly inactivated by the compound at the concentrations tested. Characterization of the mode of action of this compound against HSV-1 multiplication revealed that it inhibits the viral growth primarily at the initial step of virus multiplication, i.e., within 2 h after the onset of multiplication, although the virus multiplication was affected by the compound throughout the multiplication cycle. In addition, this compound showed a significant cytotoxic effect, although the observed antiviral effect was unlikely to be attributed to the cytotoxic effect.
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Tanaka S, Nakajima K, Hirano T, Oka K, Saito T, Wakata N. Suppressive potencies of calcineurin inhibitors against the mitogen-induced blastogenesis of peripheral-blood mononuclear cells of myasthenia gravis patients. J Pharm Pharmacol 2010. [DOI: 10.1211/jpp.60.10.0010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Abstract
The calcineurin inhibitors, tacrolimus and ciclosporin, are two useful immunosuppressive drugs for the treatment of myasthenia gravis (MG), for patients who have low responses to glucocorticoids. We have studied the suppressive potencies of tacrolimus and ciclosporin on concanavalin A-induced blastogenesis of peripheral-blood mononuclear cells (PBMCs) obtained from 38 MG patients and 26 healthy volunteers. Differences in the IC50 values of the two calcineurin inhibitors between the patients and the healthy subjects were evaluated. The median (range) IC50 values for tacrolimus and ciclosporin on the blastogenesis of PBMCs of MG patients were 0.06 (0.001–100) and 0.41 (0.09–83.0) ng mL−1, respectively. In contrast, the median (range) IC50 values of tacrolimus and ciclosporin on healthy PBMCs were 0.16 (0.001–0.33) and 5.59 (1.4–31.3), respectively, and thus ciclosporin potencies against PBMCs of MG patients were significantly higher than those against PBMCs of healthy subjects (P < 0.0001). The differences in tacrolimus IC50 values between the patients and healthy subjects were not significant. There was a correlation between ciclosporin IC50 values against the blastogenesis of PBMCs of MG patients and the duration of the disease (r = 0.35, P = 0.049). A significant correlation between the IC50 values of ciclosporin and those of prednisolone against the blastogenesis of PBMCs of MG patients was also observed (r = 0.56, P = 0.003). Furthermore, the ciclosporin IC50 values significantly correlated with the periods of glucocorticoid administration for MG treatment (r = 0.42, P = 0.038). Such correlations were not observed with the tacrolimus IC50 values. These results suggested that glucocorticoid administration had an influence on PBMC response to the suppressive efficacy of ciclosporin in MG.
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