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Goto S, Nagao K, Bannai M, Takahashi M, Nakahara K, Kangawa K, Murakami N. Anorexia in rats caused by a valine-deficient diet is not ameliorated by systemic ghrelin treatment. Neuroscience 2009; 166:333-40. [PMID: 20006681 DOI: 10.1016/j.neuroscience.2009.12.013] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2009] [Revised: 11/26/2009] [Accepted: 12/04/2009] [Indexed: 11/28/2022]
Abstract
Rodents exhibit aversive behavior toward a diet that lacks at least one of the essential amino acids. We sought to determine whether the particular form of anorexia caused by such diets could be ameliorated by the administration of orexigenic peptides while simultaneously analyzing the neural mechanisms underlying anorexia. Rats were fed a valine-deficient diet, which induced severe anorexia (reducing food consumption by 80%). The severe anorexia was associated with a significant decrease in the cerebrospinal fluid valine concentration and hyper-ghrelinemia. Between 6 and 12 days after initiation of the valine-deficient diet, we injected rats twice daily with valine and/or an orexigenic peptide (ghrelin, neuropeptide Y, or agouti-related protein) either i.p. or i.c.v.. We then measured dietary intake. An i.c.v. valine injection allowed earlier food intake compared with an i.p valine injection and increased the density of c-Fos-positive ependymal cells lining the third ventricle. Whereas an i.c.v. injection of ghrelin or neuropeptide Y increased consumption of the valine-deficient diet, i.p injection of ghrelin or i.c.v. injection of agouti-related protein did not. Following i.c.v. administration of either valine or ghrelin, we did not observe complete recovery of consumption of the valine-deficient diet. This may be due to the ineffectiveness of peripheral ghrelin and central agouti-related protein and/or to conditioned aversion to the valine-deficient diet. Since ghrelin is known to be involved in food anticipatory activities, whether the hyper-ghrelinemia observed in valine-deficient rats play role in foraging behavior other than food intake is the future study to be investigated.
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Subbarao GV, Nakahara K, Hurtado MP, Ono H, Moreta DE, Salcedo AF, Yoshihashi AT, Ishikawa T, Ishitani M, Ohnishi-Kameyama M, Yoshida M, Rondon M, Rao IM, Lascano CE, Berry WL, Ito O. Evidence for biological nitrification inhibition in Brachiaria pastures. Proc Natl Acad Sci U S A 2009; 106:17302-7. [PMID: 19805171 PMCID: PMC2752401 DOI: 10.1073/pnas.0903694106] [Citation(s) in RCA: 152] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2009] [Indexed: 11/18/2022] Open
Abstract
Nitrification, a key process in the global nitrogen cycle that generates nitrate through microbial activity, may enhance losses of fertilizer nitrogen by leaching and denitrification. Certain plants can suppress soil-nitrification by releasing inhibitors from roots, a phenomenon termed biological nitrification inhibition (BNI). Here, we report the discovery of an effective nitrification inhibitor in the root-exudates of the tropical forage grass Brachiaria humidicola (Rendle) Schweick. Named "brachialactone," this inhibitor is a recently discovered cyclic diterpene with a unique 5-8-5-membered ring system and a gamma-lactone ring. It contributed 60-90% of the inhibitory activity released from the roots of this tropical grass. Unlike nitrapyrin (a synthetic nitrification inhibitor), which affects only the ammonia monooxygenase (AMO) pathway, brachialactone appears to block both AMO and hydroxylamine oxidoreductase enzymatic pathways in Nitrosomonas. Release of this inhibitor is a regulated plant function, triggered and sustained by the availability of ammonium (NH(4)(+)) in the root environment. Brachialactone release is restricted to those roots that are directly exposed to NH(4)(+). Within 3 years of establishment, Brachiaria pastures have suppressed soil nitrifier populations (determined as amoA genes; ammonia-oxidizing bacteria and ammonia-oxidizing archaea), along with nitrification and nitrous oxide emissions. These findings provide direct evidence for the existence and active regulation of a nitrification inhibitor (or inhibitors) release from tropical pasture root systems. Exploiting the BNI function could become a powerful strategy toward the development of low-nitrifying agronomic systems, benefiting both agriculture and the environment.
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Sawabe M, Tanaka N, Nakahara K, Hamamatsu A, Chida K, Arai T, Harada K, Inamatsu T, Ozawa T, Naka MM, Matsushita S. High lipoprotein(a) level promotes both coronary atherosclerosis and myocardial infarction: a path analysis using a large number of autopsy cases. Heart 2009; 95:1997-2002. [DOI: 10.1136/hrt.2008.160879] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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Someda H, Saka H, Matsunaga S, Ide Y, Nakahara K, Hirata S, Hashimoto M. Age estimation based on three-dimensional measurement of mandibular central incisors in Japanese. Forensic Sci Int 2009; 185:110-4. [PMID: 19201557 DOI: 10.1016/j.forsciint.2009.01.001] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2008] [Revised: 12/18/2008] [Accepted: 01/01/2009] [Indexed: 10/21/2022]
Abstract
The purpose of this study was to investigate an age estimation method that considers gender as well as three-dimensional measurement of the components, specifically enamel and dentin. A total of 155 mandibular central incisors aged 12-79 years old which was chosen from the collection stored at the Department of Anatomy in Tokyo Dental College and had no opened apex, caries or restorative treatment, were examined. Samples were scanned using micro-CT HMX225 ACTIS4. Based on the sliced image data, three-dimensional structures were obtained and the volumes of enamel, dentin, and pulp cavity were measured. Regression equations for age estimation were then determined. The accuracy of age estimation equations for each region, volume ratio, and sex was assessed using the determination coefficient R(2) as well as the standard errors of estimated values. The root region alone had a comparable accuracy to that of the whole tooth and the crown region had a relatively lower accuracy. In the whole tooth and the crown region, slightly higher correlations were observed for pulp/tooth volume ratios in which enamel was excluded. Females tended to have higher accuracy compared to males. The estimated age was higher in males compared to females for the same volume ratio of the pulp cavity. The highest correlation in both genders with age was observed for the volume ratio of the pulp cavity to the whole tooth excluding the enamel (males, R(2)=0.67; females, R(2)=0.76). The 95% confidence intervals for the population regression showed different distributions for each sex. In the 95% prediction intervals for age estimation, females tended to have narrower intervals and higher accuracy compared to males. Therefore, the use of gender-specific equations is recommended for age estimation.
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Kojimahara T, Nakahara K, Osakabe M, Saitoh-Sekiguchi M, Hayasaka T, Motoyama T, Kurachi H. Risk factors for recurrence of optimally staged/debulked ovarian or tubal cancer patients with adjuvant paclitaxel/carboplatin combination chemotherapy. J Clin Oncol 2008. [DOI: 10.1200/jco.2008.26.15_suppl.16571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Armstrong DS, Arvieux J, Asaturyan R, Averett T, Bailey SL, Batigne G, Beck DH, Beise EJ, Benesch J, Bimbot L, Birchall J, Biselli A, Bosted P, Boukobza E, Breuer H, Carlini R, Carr R, Chant N, Chao YC, Chattopadhyay S, Clark R, Covrig S, Cowley A, Dale D, Davis C, Falk W, Finn JM, Forest T, Franklin G, Furget C, Gaskell D, Grames J, Griffioen KA, Grimm K, Guillon B, Guler H, Hannelius L, Hasty R, Allen AH, Horn T, Johnston K, Jones M, Kammel P, Kazimi R, King PM, Kolarkar A, Korkmaz E, Korsch W, Kox S, Kuhn J, Lachniet J, Lee L, Lenoble J, Liatard E, Liu J, Loupias B, Lung A, Marchand D, Martin JW, McFarlane KW, McKee DW, McKeown RD, Merchez F, Mkrtchyan H, Moffit B, Morlet M, Nakagawa I, Nakahara K, Neveling R, Ong S, Page S, Papavassiliou V, Pate SF, Phillips SK, Pitt ML, Poelker M, Porcelli TA, Quéméner G, Quinn B, Ramsay WD, Rauf AW, Real JS, Roche J, Roos P, Rutledge GA, Secrest J, Simicevic N, Smith GR, Spayde DT, Stepanyan S, Stutzman M, Sulkosky V, Tadevosyan V, Tieulent R, Van de Wiele J, van Oers WTH, Voutier E, Vulcan W, Warren G, Wells SP, Williamson SE, Wood SA, Yan C, Yun J, Zeps V. Transverse beam spin asymmetries in forward-angle elastic electron-proton scattering. PHYSICAL REVIEW LETTERS 2007; 99:092301. [PMID: 17930999 DOI: 10.1103/physrevlett.99.092301] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2007] [Indexed: 05/25/2023]
Abstract
We have measured the beam-normal single-spin asymmetry in elastic scattering of transversely polarized 3 GeV electrons from unpolarized protons at Q2=0.15, 0.25 (GeV/c)2. The results are inconsistent with calculations solely using the elastic nucleon intermediate state and generally agree with calculations with significant inelastic hadronic intermediate state contributions. A(n) provides a direct probe of the imaginary component of the 2gamma exchange amplitude, the complete description of which is important in the interpretation of data from precision electron-scattering experiments.
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Kim K, Lee YS, Harris D, Nakahara K, Carthew RW. The RNAi pathway initiated by Dicer-2 in Drosophila. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 2007; 71:39-44. [PMID: 17381278 DOI: 10.1101/sqb.2006.71.008] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Injection or expression of double-stranded RNA (dsRNA) in Drosophila serves as a trigger that causes cells to specifically cleave homologous mRNA transcripts. Our approach is to identify essential components of the RNA interference (RNAi) mechanism by isolating and characterizing mutations that cause the RNAi response to be abnormal. These studies have thus far led to the identification of seven genetic loci that encode proteins acting at various steps in the RNAi process. We have molecularly identified several of these proteins. Two are members of the Dicer family. Dicer-1 and Dicer-2 are required for short interfering RNA (siRNA)-directed mRNA cleavage by facilitating distinct steps in the assembly of the RNA-induced silencing complex (RISC). AGO2 is a RISC component that both carries out transcript cleavage and facilitates RISC maturation. Other factors appear to function as regulators of RISC assembly rather than as core factors for RNAi.
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Fukushima Y, Oka H, Utsuki S, Nakahara K, Fujii K. Primary malignant lymphoma of the cranial vault. Acta Neurochir (Wien) 2007; 149:601-4. [PMID: 17460815 DOI: 10.1007/s00701-007-1156-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2006] [Accepted: 03/27/2007] [Indexed: 10/23/2022]
Abstract
A 60-year-old woman presented with a subcutaneous mass on her scalp. Computed tomography (CT) showed a homogeneously enhanced mass of the parietal bone with both intra- and extra-calvarial extension and having destroyed the right parietal bone. The mass was hypointense on the T1-weighted magnetic resonance image, slightly hyperintense on the T2-weighted image and homogenously enhanced with Gd-DTPA. Bone scintigraphy showed prominent accumulation of radioisotopes in the scalp lesion. The tumour was removed, including the involved bone and dura mater. Histologic diagnosis was non-Hodgkin's B-cell lymphoma, and tumour cells had infiltrated into the dura mater. The patient was treated with radiotherapy and chemotherapy. She returned to ordinary daily life and has been well without recurrence for 3 years. Although primary malignant lymphoma of the cranial vault is rare, it should be considered in the differential diagnosis when a mass is encountered in the cranial vault. We have found only fourteen such cases in the literature, and we review these cases.
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Roy MK, Nakahara K, Na TV, Trakoontivakorn G, Takenaka M, Isobe S, Tsushida T. Baicalein, a flavonoid extracted from a methanolic extract of Oroxylum indicum inhibits proliferation of a cancer cell line in vitro via induction of apoptosis. DIE PHARMAZIE 2007; 62:149-53. [PMID: 17341037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
A methanolic extract of the fruits of Oroxylum indicum, which is widely used in traditional Chinese herbal medicine for its anti-inflammatory, anti-pyretic and anti-hypersensitivity effects, inhibited in vitro proliferation of HL-60 cells. The flavonoid baicalein was found as an active component in the extract. Analysis of freeze-dried fruits of the plant indicated that this component comprised about 4% of the material by dry weight. In this study, we investigated the in vitro effects of baicalein on the viability and induction of apoptosis in the HL-60 cell line. The cell viability after treating with baicalein for 24 h was quantified by counting viable cells using trypan blue staining. The results showed that baicalein caused a 50% inhibition of HL-60 cells at concentrations of 25-30 microM. The inhibition of proliferation of HL-60 cells due to 36-48 h exposure to 10 or 20 microM baicalein was associated with the accumulation of cells at S or G2M phases. However, proliferation inhibition at a higher dose may be associated with induction by apoptosis, as evidenced by the typical nuclear fragmentation using DNA fragmentation assay and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL). The results indicate that baicalein has anti-tumor effects on human cancer cells, and Oroxylum indicum extract could be used in supplementary cancer therapy.
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Yokoyama Y, Moriya T, Takano T, Shoji T, Takahashi O, Nakahara K, Yamada H, Yaegashi N, Okamura K, Izutsu T, Sugiyama T, Tanaka T, Kurachi H, Sato A, Tase T, Mizunuma H. Clinical outcome and risk factors for recurrence in borderline ovarian tumours. Br J Cancer 2006; 94:1586-91. [PMID: 16685277 PMCID: PMC2361313 DOI: 10.1038/sj.bjc.6603139] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
We investigated the long-term prognosis of borderline ovarian tumours and determined risk factors for recurrence. One hundred and twenty-one borderline ovarian tumours treated between 1994 and 2003 at the participating institutions in the Tohoku Gynecologic Cancer Unit were retrospectively investigated for clinical stage, histopathological subtype, surgical technique, postoperative chemotherapy, the presence or absence of recurrence, and prognosis. The median follow-up period was 57 months (1-126 months). One hundred and nine cases (90.6%) were at clinical stage I. The histopathological subtypes consisted of 91 cases of mucinous tumour (75.2%), 27 cases of serous tumour (22.3%), and three cases of endometrioid tumour. Conservative surgery was used in 53 cases (43.8%), radical surgery in 68 cases (56.2%), a staging laparotomy in 43 cases (35.5%), and postoperative adjuvant therapy in 30 cases (24.8%). Recurrence was found in eight cases, but no tumour-related deaths were reported. Although no significant difference in disease-free survival rate was seen between different clinical stages, the difference in disease-free survival rate between serous and non-serous (mucinous and endometrioid) types was significant (P<0.05). The 10-year disease-free survival rate was 89.1% for the radical surgery group and 57.4% for the conservative surgery group -- this difference was significant (P<0.05). In the conservative surgery group, cystectomy and serous tumour were independent risk factors for recurrence. Although recurrence was observed, the long-term prognosis of borderline ovarian tumour was favourable, without tumour-related deaths. Considering the favourable prognosis, conservative surgery can be chosen as far as the patient has a non-serous tumour and receive adnexectomy. However, in cases of serous type and/or receiving cystectomy special care should be given as relative risk rates of recurrence elevate by 2-4-folds.
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Imai E, Fujii M, Kohno Y, Kageyama H, Nakahara K, Hori M, Tsubakihara Y. Adenosine A1 receptor antagonist improves intradialytic hypotension. Kidney Int 2006; 69:877-83. [PMID: 16395260 DOI: 10.1038/sj.ki.5000088] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Intradialytic hypotension is a most frequent complication of hemodialysis and may contribute to cardiovascular events and high mortality. There is a hypothesis that an increase in adenosine generation during hemodialysis may cause vasodilation and a decrease in cardiac output, which results in systemic hypotension. We studied whether this can be blocked by an adenosine A1 receptor antagonist. We investigated the effects of an A1 antagonist, FK352, injection in 30 chronic hemodialysis patients with frequent intradialytic hypotension by a prospective, multicenter, double-blind placebo-controlled study for 4 weeks after 4 weeks of the observation period. Intradialytic hypotension was defined as systolic blood pressure (SBP) less than 110 mmHg, with SBP drop of more than 30 mmHg from the predialysis level. The efficacy of FK352 was primarily assessed by the reduction rate of dialysis hypotension between the FK352 and placebo groups. Incidence of emergency treatments caused by hypotension was evaluated. FK352 (50 mg, intravenous) or an equivalent placebo was injected into the dialysis circuit 1 h after starting dialysis. Blood pressure and heart rate were monitored every 30 min during dialysis. FK352 significantly improved intradialytic hypotension (P=0.046), in that the reduction rates of intradialytic hypotension in the FK352 and placebo groups were -12.8% (Q1 (first quantile), Q3 (third quantile): -27.5, -1.7), and +8.3% (Q1, Q3: -16.6, +16.7), respectively. The frequency of discontinuation of dialysis was significantly reduced by FK352. No apparent side effects were observed from treatment with FK352. In conclusion, the A1 antagonist FK352 may offer a novel therapeutic option for chronic dialysis patients associated with intradialytic hypotension.
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Armstrong DS, Arvieux J, Asaturyan R, Averett T, Bailey SL, Batigne G, Beck DH, Beise EJ, Benesch J, Bimbot L, Birchall J, Biselli A, Bosted P, Boukobza E, Breuer H, Carlini R, Carr R, Chant N, Chao YC, Chattopadhyay S, Clark R, Covrig S, Cowley A, Dale D, Davis C, Falk W, Finn JM, Forest T, Franklin G, Furget C, Gaskell D, Grames J, Griffioen KA, Grimm K, Guillon B, Guler H, Hannelius L, Hasty R, Hawthorne Allen A, Horn T, Johnston K, Jones M, Kammel P, Kazimi R, King PM, Kolarkar A, Korkmaz E, Korsch W, Kox S, Kuhn J, Lachniet J, Lee L, Lenoble J, Liatard E, Liu J, Loupias B, Lung A, MacLachlan GA, Marchand D, Martin JW, McFarlane KW, McKee DW, McKeown RD, Merchez F, Mkrtchyan H, Moffit B, Morlet M, Nakagawa I, Nakahara K, Nakos M, Neveling R, Niccolai S, Ong S, Page S, Papavassiliou V, Pate SF, Phillips SK, Pitt ML, Poelker M, Porcelli TA, Quéméner G, Quinn B, Ramsay WD, Rauf AW, Real JS, Roche J, Roos P, Rutledge GA, Secrest J, Simicevic N, Smith GR, Spayde DT, Stepanyan S, Stutzman M, Sulkosky V, Tadevosyan V, Tieulent R, van de Wiele J, van Oers W, Voutier E, Vulcan W, Warren G, Wells SP, Williamson SE, Wood SA, Yan C, Yun J, Zeps V. Strange-quark contributions to parity-violating asymmetries in the forward g0 electron-proton scattering experiment. PHYSICAL REVIEW LETTERS 2005; 95:092001. [PMID: 16197209 DOI: 10.1103/physrevlett.95.092001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2005] [Indexed: 05/04/2023]
Abstract
We have measured parity-violating asymmetries in elastic electron-proton scattering over the range of momentum transfers 0.12 < or =Q2 < or =1.0 GeV2. These asymmetries, arising from interference of the electromagnetic and neutral weak interactions, are sensitive to strange-quark contributions to the currents of the proton. The measurements were made at Jefferson Laboratory using a toroidal spectrometer to detect the recoiling protons from a liquid hydrogen target. The results indicate nonzero, Q2 dependent, strange-quark contributions and provide new information beyond that obtained in previous experiments.
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Nobuhara Y, Nakahara K, Higuchi I, Yoshida T, Fushiki S, Osame M, Arimura K, Nakagawa M. Juvenile form of Alexander disease with GFAP mutation and mitochondrial abnormality. Neurology 2005; 63:1302-4. [PMID: 15477559 DOI: 10.1212/01.wnl.0000140695.90497.e2] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The authors report a 29-year-old woman with marked atrophy of the cerebellum, medulla oblongata, and spinal cord, dementia, diffuse white matter abnormality on MRI, ragged-red fibers, and R88C mutation in the human glial fibrillary acidic protein (GFAP). Mitochondria DNA (mtDNA) analysis showed a rare polymorphism at A8291G. This mtDNA polymorphism, which has been associated with limb-girdle type mitochondrial myopathy, may modify the clinical symptoms of this juvenile form of Alexander disease with GFAP mutation.
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Hatfield SD, Shcherbata HR, Fischer KA, Nakahara K, Carthew RW, Ruohola-Baker H. Stem cell division is regulated by the microRNA pathway. Nature 2005; 435:974-8. [PMID: 15944714 DOI: 10.1038/nature03816] [Citation(s) in RCA: 523] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2005] [Accepted: 05/16/2005] [Indexed: 01/07/2023]
Abstract
One of the key characteristics of stem cells is their capacity to divide for long periods of time in an environment where most of the cells are quiescent. Therefore, a critical question in stem cell biology is how stem cells escape cell division stop signals. Here, we report the necessity of the microRNA (miRNA) pathway for proper control of germline stem cell (GSC) division in Drosophila melanogaster. Analysis of GSCs mutant for dicer-1 (dcr-1), the double-stranded RNaseIII essential for miRNA biogenesis, revealed a marked reduction in the rate of germline cyst production. These dcr-1 mutant GSCs exhibit normal identity but are defective in cell cycle control. On the basis of cell cycle markers and genetic interactions, we conclude that dcr-1 mutant GSCs are delayed in the G1 to S transition, which is dependent on the cyclin-dependent kinase inhibitor Dacapo, suggesting that miRNAs are required for stem cells to bypass the normal G1/S checkpoint. Hence, the miRNA pathway might be part of a mechanism that makes stem cells insensitive to environmental signals that normally stop the cell cycle at the G1/S transition.
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Shibata H, Watanabe M, Sakai M, Oka K, Fons P, Iwata K, Yamada A, Matsubara K, Sakurai K, Tampo H, Nakahara K, Niki S. Characterization of ZnO crystals by photoluminescence spectroscopy. ACTA ACUST UNITED AC 2004. [DOI: 10.1002/pssc.200304149] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Mori-Abe A, Tsutsumi S, Takahashi K, Toya M, Yoshida M, Du B, Kawagoe J, Nakahara K, Takahashi T, Ohmichi M, Kurachi H. Estrogen and raloxifene induce apoptosis by activating p38 mitogen-activated protein kinase cascade in synthetic vascular smooth muscle cells. J Endocrinol 2003; 178:417-26. [PMID: 12967334 DOI: 10.1677/joe.0.1780417] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Proliferation of vascular smooth muscle cells (VSMC) plays a major role as an initiating event of atherosclerosis. Although estrogen directly inhibits the proliferation of VSMC, the mechanism has not been firmly established. In addition, the effect of raloxifene on VSMC remains unknown. 17Beta-estradiol (E(2)) and raloxifene significantly inhibited the growth of VSMC under growth-stimulated conditions. Since mitogen-activated protein (MAP) kinases have been implicated in VSMC proliferation, the role of MAP kinases in both the E(2)- and raloxifene-induced growth inhibition of VSMC was studied. Both E(2) and raloxifene caused rapid, transient phosphorylation and activation of p38 that was not affected by actinomycin D and was blocked by ICI 182,780. In contrast with p38 phosphorylation, extracellular signal-regulated protein kinase (ERK) phosphorylation was significantly inhibited and c-Jun N-terminal kinase (JNK) phosphorylation was not changed by E(2). Because VSMC expressed both estrogen receptor (ER) alpha and ERbeta, it is not known which of them mediates the E(2)-induced phosphorylation of p38. Although E(2) did not affect the p38 phosphorylation in A10 smooth muscle cells, which express ERbeta but not ERalpha, transfection of ERalpha expression vector into A10 cells rendered them susceptible to induction of p38 phosphorylation by E(2). We then examined whether E(2) and raloxifene induce apoptosis through a p38 cascade. Both E(2) and raloxifene induced apoptosis under growth-stimulated conditions. The p38 inhibitor SB 203580 completely blocked the E(2)-induced apoptosis. Our findings suggest that both E(2)- and raloxifene-induced inhibition of VSMC growth is due to induction of apoptosis through a p38 cascade whose activation is mediated by ERalpha via a nongenomic mechanism.
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Yoshida M, Horimoto H, Mieno S, Nomura Y, Okawa H, Nakahara K, Sasaki S. Intra-arterial bone marrow cell transplantation induces angiogenesis in rat hindlimb ischemia. Eur Surg Res 2003; 35:86-91. [PMID: 12679617 DOI: 10.1159/000069401] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2002] [Accepted: 10/02/2002] [Indexed: 11/19/2022]
Abstract
BACKGROUND Bone marrow (BM) cells have been shown to augment local angiogenesis by differentiating vessels themselves and/or secreting paracrinally angiogenic growth factors. Herein, the angiogenic effects of intra-arterial BM mononuclear cell (BM-MNC) transplantation were evaluated in a rat ischemic hindlimb model. METHODS Unilateral hindlimb ischemia was created by excising the femoral artery and its branch in Lewis rats. BM-MNCs were isolated by centrifugation through a Histopaque density gradient. One week after excision of the unilateral femoral artery, BM-MNCs (5 x 10(6) cells, Group A, n = 6) or PBS (Group B, n = 7) were injected into the ischemic thigh skeletal muscles at the six points with a gauge needle. Another injection of BM-MNCs (3 x 10(7) cells, Group C, n = 6) or PBS (Group D, n = 7) was administered via the indwelling catheter in the right common iliac artery. RESULTS Four weeks after the BM-MNC transplantation, angiographic examination revealed the development of collateral vessels in both BM-MNC-transplanted groups. The difference in skin temperature between right and left hindlimbs was significantly reduced in both BM-MNC-transplanted groups (0.93 +/- 0.15 vs. 2.84 +/- 0.35 vs. 1.20 +/- 0.26 vs. 2.61 +/- 0.37 degrees C, Group A vs. Group B vs. Group C vs. Group D, p < 0.05). Moreover, immunohistochemical analysis demonstrated that capillary endothelial cells were increased in both BM-MNC-transplanted groups. CONCLUSION BM-MNC implantation was able to induce functional neovascularization in rat ischemic hindlimb. The intra-arterial administration offered similar levels of angiogenic activity as intramuscular injection.
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Nakahara K, Horimoto H, Nakai Y, Mieno S, Nomura Y, Sasaki S. Left ventricular mechanical unloading restores Beta-2-adrenergic receptor mRNA expression and decreases susceptibility to ischemia and reperfusion in the failing heart. Eur Surg Res 2003; 35:108-14. [PMID: 12679621 DOI: 10.1159/000069396] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2002] [Indexed: 11/19/2022]
Abstract
OBJECTIVES Left ventricular (LV) mechanical unloading is known to reduce the hemodynamic demands of failing LV, resulting in improved myocyte contractility. This study was designed to examine effects of LV unloading on beta-adrenergic receptor (BAR) expression and ischemic susceptibility to ischemia reperfusion. METHODS Five groups were studied: group 1 [unloading myocardial infarction (MI), n = 6], MI hearts 2 weeks after coronary ligation subjected to LV unloading by heterotopic heart transplantation for 2 weeks; group 2 (2-week MI, n = 6), MI hearts left for 2 weeks without unloading; group 3 (4-week MI, n = 6), MI hearts left for 4 weeks without unloading; group 4 (control, n = 6), normal (non-MI) hearts as a control with no interventions, and group 5 (unloading control, n = 5), normal (non-MI) hearts subjected to LV unloading for 2 weeks. Then, all hearts were isolated and subjected to 20 min of global ischemia and 60 min of reperfusion on Langendorff apparatus. LV pressures and coronary flow were measured throughout the experiment. Either total BAR density or beta(2)-adrenergic receptor (B2AR) mRNA expression in the noninfarcted myocardium was determined by radioligand binding assays or real-time quantitative RT-PCR, respectively. RESULTS LV unloading improved postischemic functional recovery (unloading MI vs. 2-week MI vs. 4-week MI: 74 +/- 6 vs. 54 +/- 5 vs. 51 +/- 4%; p < 0.05 vs. unloading MI). LV unloading restored B2AR mRNA expression (unloading MI vs. 2-week MI vs. 4-week MI: 4.78 +/- 0.21 vs. 2.80 +/- 0.19 vs. 2.24 +/- 0.17 x 10(7) copy/microg total RNA; p < 0.05 vs. unloading MI). CONCLUSION LV mechanical unloading restored B2AR mRNA expression and improved postischemic functional recovery.
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Alzoreky NS, Nakahara K. Antibacterial activity of extracts from some edible plants commonly consumed in Asia. Int J Food Microbiol 2003; 80:223-30. [PMID: 12423924 DOI: 10.1016/s0168-1605(02)00169-1] [Citation(s) in RCA: 258] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Extracts of edible plants (26 species) from China, Japan, Thailand and Yemen were screened for their antibacterial activity against Bacillus cereus, Staphylococcus aureus, Listeria monocytogenes, Escherichia coli and Salmonella infantis. Buffered methanol (80% methanol and 20% PBS) and acetone extracted inhibitory substances against tested bacteria from 16 plants, as revealed by the disc assay. The minimum inhibitory concentrations (MICs) of extracts determined by the agar dilution method ranged from 165 to 2640 mg l(-1). The most sensitive microorganism to extracts from Azadirachta indica, Cinnamomum cassia, Rumex nervosus, Ruta graveolens, Thymus serpyllum and Zingiber officinale was B. cereus, with MIC of 165 to 660 mg l(-1). E. coli and S. infantis were only inhibited by Cinnamomum cassia extracts at the highest MIC (2640 mg l(-1)). L. monocytogenes (Tottori) was more resistant than the ATCC 7644 strain to extracts from Ruta chalepensis, Artemisia absinthium and Cissus spp. EDTA (0.85 mM) reduced the MICs of Cinnamomum cassia and Cissus rotundifolia by at least 50% when tested against E. coli, S. infantis, S. aureus and L. monocytogenes.
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Horimoto S, Horimoto H, Mieno S, Nakahara K, Nakai Y, Yoshida M, Sasaki S. Left ventricular mechanical unloading decreases ischemic susceptibility by modulating angiotensin II type-2 receptor gene experssion in the failing heart after myocardial infarction. J Heart Lung Transplant 2003. [DOI: 10.1016/s1053-2498(02)01073-2] [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] Open
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Morio A, Nakahara K, Ohse Y, Tahara M, Gotoh T, Masuda S, Yakumaru K. [Induction chemoradiotherapy in small adenocarcinoma of the lung with bulky mediatinal lymph node metastasis]. KYOBU GEKA. THE JAPANESE JOURNAL OF THORACIC SURGERY 2002; 55:1097-100. [PMID: 12476556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
A 56-year-old man, who visited our hospital due to chest pain, was pointed out a large tumor, 60 mm in diameter, on the left superior mediastinum on the chest computed tomography (CT) scan. He was diagnosed as having mediastinal lymph nodes metastasis of adenocarcinoma through video-assisted thoracoscopic surgery (VATS) biopsy. He received induction chemoradiotherapy: cisplatin and paclitaxel were administered once per week for 2 weeks, and radiotherapy was simultaneously performed. No serious adverse reactions were noted. The ipsilateral mediastinal lymph nodes dissection was performed. Intraoperative frozen section analysis showed a small nodule in the left upper lobe, 5 mm in diameter, was adenocarcinoma. He was finally diagnosed as having mediastinal lymph nodes metastasis from the small adenocarcinoma of the lung, and left upper lobectomy was performed. Histopathological examination of the mediastinal lymph nodes showed no evidence of viable maligmant cell. Induction chemoradiotherapy with cisplatin and paclitaxel might be effective treatment for locally advanced non-small cell lung cancer.
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Murakami N, Hayashida T, Kuroiwa T, Nakahara K, Ida T, Mondal MS, Nakazato M, Kojima M, Kangawa K. Role for central ghrelin in food intake and secretion profile of stomach ghrelin in rats. J Endocrinol 2002; 174:283-8. [PMID: 12176667 DOI: 10.1677/joe.0.1740283] [Citation(s) in RCA: 177] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Ghrelin, a 28-amino-acid peptide, has recently been isolated from the rat stomach as an endogenous ligand for the GH secretagogue receptor. We have reported previously that central or peripheral administration of ghrelin stimulates food intake, and the secretion of GH and gastric acid in rats. In the present study, we investigated how much endogenous centrally released ghrelin is involved in the control of food intake and body weight gain. We also examined the profile of ghrelin secretion from the stomach by RIA using two kinds of anti-ghrelin antiserum, one raised against the N-terminal ([Cys(12)]-ghrelin[1-11]) region and one raised against the C-terminal ([Cys(0)]-ghrelin [13-28]) region of the peptide. The former antibody recognizes specifically ghrelin with n- octanoylated Ser 3 (acyl ghrelin), and does not recognize des-acyl ghrelin. The latter also recognizes des-acyl ghrelin (i.e. total ghrelin). Intracerebroventricular treatment with the anti-ghrelin antiserum against the N-terminal region twice a day for 5 days decreased significantly both daily food intake and body weight. Des-acyl ghrelin levels were significantly higher in the gastric vein than in the trunk. Either fasting for 12 h, administration of gastrin or cholecystokinin resulted in increase of both acyl and des-acyl ghrelin levels. The ghrelin levels exhibited a diurnal pattern, with the bimodal peaks occurring before dark and light periods. These two peaks were consistent with maximum and minimum volumes of gastric content respectively. These results suggest that (1) endogenous centrally released ghrelin participates in the regulation of food intake and body weight, (2) acyl ghrelin is secreted from the stomach, (3) intestinal hormones stimulate ghrelin release from the stomach, and (4) regulation of the diurnal rhythm of ghrelin is complex, since ghrelin secretion is augmented under conditions of both gastric emptying and filling.
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Iino T, Nakahara K, Miki W, Kiso Y, Ogawa Y, Kato S, Takeuchi K. Less damaging effect of whisky in rat stomachs in comparison with pure ethanol. Role of ellagic acid, the nonalcoholic component. Digestion 2002; 64:214-21. [PMID: 11842277 DOI: 10.1159/000048864] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND/AIM Ellagic acid (EA), one of the polyphenols that are abundantly contained in whisky as a nonalcoholic component, has antioxidant and anti-inflammatory activities. In the present study, we compared the action of whisky and pure ethanol on the rat gastric mucosa, and examined the role of EA in the less-damaging effect of whisky in the stomach. METHODS Under urethane anesthesia, a rat stomach was mounted in an ex vivo chamber, perfused with saline, and the transmucosal potential difference (PD) was measured before and after exposure to whisky (Yamazaki, Suntory) and ethanol (43%). In a separate study, the animals were given whisky or ethanol (1 ml, 43%) p.o. under unanesthetized conditions, killed 1 h later, and the gastric mucosa was examined for hemorrhagic lesions. RESULTS Both whisky and ethanol caused a PD reduction, resulting in damage in the stomach, but these responses were less marked in the case of whisky. Although the reduced PD recovered gradually after removal of ethanol, this process was significantly expedited by co-application of EA (80 microg/ml), the recovery rate being much the same as that observed after exposure to whisky. The less-damaging effect of whisky was confirmed in unanesthetized rats after p.o. administration of these agents. In addition, EA (1-30 mg/kg), administered p.o. together with absolute ethanol (99.9%), reduced the severity of gastric lesions induced by ethanol, in a dose-dependent manner, and the effect at 30 mg/kg was equivalent to that obtained by the whisky component containing several low- and high-molecular-weight polyphenols. EA had a scavenging action against both oxygen and hydroxyl radicals in vitro, the effect being equivalent to that of catechol or alpha-tocopherol. CONCLUSION These results suggest that whisky is less irritating to the gastric mucosa, as compared with pure ethanol, and this property of whisky may be explained by EA, one of polyphenols contained in whisky, and its radical scavenging action.
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Suzuki S, Kurata A, Takagi H, Nakahara K, Oka H, Miyasaka Y, Fujii K. Superselective arterial chemotherapy for inoperable metastases in the dura mater and cranium. Interv Neuroradiol 2002; 8:121-5. [PMID: 20594520 PMCID: PMC3576605 DOI: 10.1177/159101990200800203] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2002] [Accepted: 05/09/2002] [Indexed: 11/17/2022] Open
Abstract
SUMMARY Diffuse metastases to the cranium and dura mater of the bilateral hemisphere do not allow surgical intervention. We describe an excellent case which was treated by intra-arterial chemotherapy using Epirubicine (Farumorbicine). A 58-year-old woman treated for breast cancer ten years ago was admitted to our hospital with headache and frontal mass lesions.Magnetic resonance (MR) imaging on admission revealed a remarkable enhanced lesion of the bilateral dura mater and cranium, and bilateral brain edema in the frontal lobe. Angiography disclosed a vascular rich tumour supplied by bilateral external carotid artery branches.We successfully treated the lesion using superselective intra-arterial chemotherapy with a minimal dose of Epirubicine followed by embolization of bilateral external carotid artery branches. Followup MR imaging two years after the endovascular treatment showed disappearance of the enhanced lesion and remodeling of the skull bone. The patient is neurologically free of symptoms.
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Nakahara K, Iwasa S, Satoh M, Morioka Y, Iriyama J, Suguro M, Hasegawa E. Rechargeable batteries with organic radical cathodes. Chem Phys Lett 2002. [DOI: 10.1016/s0009-2614(02)00705-4] [Citation(s) in RCA: 464] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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