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Hamano S, Nomura H, Kinsui H, Oikawa T, Suzuki N, Tanaka M, Murakami S, Igarashi T, Ito H. Experience with ureteral stone management in 1,082 patients using semirigid ureteroscopes. Urol Int 2001; 65:106-11. [PMID: 11025433 DOI: 10.1159/000064849] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
OBJECTIVES To assess the efficacy and complications of ureteroscopic lithotripsy (URS) using semirigid ureteroscopes. METHODS We retrospectively analyzed the records of 1,082 consecutive patients with ureteral stones who were treated with URS with or without auxiliary extracorporeal shock wave lithotripsy for stone fragments. The efficacy was estimated using the stone-free rate and efficiency quotient (EQ). RESULTS The stone-free rates were 79.0, 90.4 and 93.2% for upper, middle and lower ureteral stones, respectively. The EQ was 0.49 for upper, 0.79 for middle and 0.87 for lower ureteral stones. Ureteral perforation occurred in 54 cases (5.0%), of which 13 cases (1.2%) required nephrostomy (n = 11, 1.0%) or open surgery (n = 2, 0.2%). CONCLUSIONS URS is a reasonable procedure with minor complications for stones located in the lower and middle ureter, but cannot be recommended as a first-line treatment for upper ureteral stones.
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Dong E, Matsumoto K, Uzunova V, Sugaya I, Takahata H, Nomura H, Watanabe H, Costa E, Guidotti A. Brain 5alpha-dihydroprogesterone and allopregnanolone synthesis in a mouse model of protracted social isolation. Proc Natl Acad Sci U S A 2001; 98:2849-54. [PMID: 11226329 PMCID: PMC30228 DOI: 10.1073/pnas.051628598] [Citation(s) in RCA: 221] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Allopregnanolone (ALLO), is a brain endogenous neurosteroid that binds with high affinity to gamma-aminobutyric acid type A (GABA(A)) receptors and positively modulates the action of GABA at these receptors. Unlike ALLO, 5alpha-dihydroprogesterone (5alpha-DHP) binds with high affinity to intracellular progesterone receptors that regulate DNA transcription. To investigate the physiological roles of ALLO and 5alpha-DHP synthesized in brain, we have adopted a mouse model involving protracted social isolation. In the frontal cortex of mice, socially isolated for 6 weeks, both neurosteroids were decreased by approximately 50%. After administration of (17beta)-17-(bis-1-methyl amino carbonyl) androstane-3,5-diene-3-carboxylic acid (SKF105,111), an inhibitor of the enzyme (5alpha-reductase Type I and II) that converts progesterone into 5alpha-DHP, the ALLO and 5alpha-DHP content of frontal cortex of both group-housed and socially isolated mice decreased exponentially to 10%-20% of control values in about 30 min. The fractional rate constants (k h(-1)) of ALLO and 5alpha-DHP decline multiplied by the ALLO and 5alpha-DHP concentrations at any given steady-state estimate the rate of synthesis required to maintain that steady state. After 6 weeks of social isolation, ALLO and 5alpha-DHP biosynthesis rates were decreased to 30% of the values calculated in group-housed mice. Moreover, in socially isolated mice, the expression of 5alpha-reductase Type I mRNA and protein was approximately 50% lower than in group-housed mice whereas 3alpha-hydroxysteroid oxidoreductase mRNA expression was equal in the two groups. Protracted social isolation in mice may provide a model to investigate whether 5alpha-DHP by a genomic action, and ALLO by a nongenomic mechanism down-regulate the action of drugs acting as agonists, partial agonists, or positive allosteric modulators of the benzodiazepine recognition sites expressed by GABA(A) receptors.
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Shiraishi M, Oshiro T, Taira K, Nozato E, Nagahama M, Nomura H, Takushi Y, Sugawa H, Muto Y. Human thrombomodulin improves the microcirculation of the xeno-perfused porcine liver. Transplant Proc 2001; 33:719-20. [PMID: 11267037 DOI: 10.1016/s0041-1345(00)02222-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Kurochkin IV, Yonemitsu N, Funahashi SI, Nomura H. ALEX1, a novel human armadillo repeat protein that is expressed differentially in normal tissues and carcinomas. Biochem Biophys Res Commun 2001; 280:340-7. [PMID: 11162520 DOI: 10.1006/bbrc.2000.4125] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Members of the armadillo (arm) repeat family of proteins are implicated in tumorigenesis, embryonic development, and maintenance of tissue integrity. We have cloned cDNA for a novel human arm repeat protein, ALEX1, encoding 453 amino acids. ALEX1 shares significant homology with uncharacterized ORF KIAA0512 and putative protein product of unknown mRNA (GenBank AF211175), designated here as ALEX2 and ALEX3, respectively. The genes encoding ALEX1, ALEX2 and ALEX3 co-localize to the same region in Xq21.33-q22.2. ALEX1 and ALEX2 transcripts are found in all human tissues examined except peripheral blood leukocytes. Expression of ALEX1 and ALEX2 mRNA is lost or significantly reduced in human lung, prostate, colon, pancreas, and ovarian carcinomas and also in cell lines established from different human carcinomas. These genes are, however, normally expressed in cell lines derived from other types of tumors, e.g., sarcomas, neuroblastomas, and gliomas. We speculate that ALEX genes may play a role in suppression of tumors originating from epithelial tissue, i.e., carcinomas.
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Rong L, Kojima Y, Koda S, Nomura H. Simple quantification of ultrasonic intensity using aqueous solution of phenolphthalein. ULTRASONICS SONOCHEMISTRY 2001; 8:11-15. [PMID: 11105317 DOI: 10.1016/s1350-4177(00)00024-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Aqueous phenolphthalein solution under sonication was investigated for use as a chemical dosimeter. The fading time of aqueous phenolphthalein solution under sonication depended on the concentration of phenolphthalein and the pH values of solutions. The fading time was correlated to the ultrasonic intensity in a reaction vessel that is estimated on the basis of decomposition of porphyrin. The relation between the fading time and the ultrasonic intensity for different frequencies is expressed by a single curve. From these results, it is indicated that aqueous solutions of phenolphthalein is useful for simple quantification of ultrasonic intensity for practical use, and one can regard it as one of the ultrasonic intensity indicators.
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Cang S, Ohta S, Chiba H, Johdo O, Nomura H, Nagamatsu Y, Yoshimoto A. New Naphthyridinomycin-type Antibiotics, Aclidinomycins A and B, from Streptomyces halstedi. J Antibiot (Tokyo) 2001; 54:304-7. [PMID: 11372787 DOI: 10.7164/antibiotics.54.304] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Konoshita T, Miyagi K, Onoe T, Katano K, Mutoh H, Nomura H, Koni I, Miyamori I, Mabuchi H. Effect of ACE gene polymorphism on age at renal death in polycystic kidney disease in Japan. Am J Kidney Dis 2001; 37:113-118. [PMID: 11136175 DOI: 10.1053/ajkd.2001.20595] [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] [Indexed: 11/11/2022]
Abstract
Polycystic kidney disease (PKD) is one of the most common genetic disorders and a major cause of renal death or end-stage renal disease (ESRD) requiring regular hemodialysis. The responsible genes recently have been cloned; however, genetic factors influencing the rate of progression to ESRD in patients with PKD have yet to be defined. Several studies have shown increased activity of the renin-angiotensin system (RAS) in patients with PKD. In addition, genetic polymorphisms of the RAS have been associated with the development of cardiovascular diseases. Therefore, these polymorphisms are good candidates for disease-modifying genetic factors or markers in PKD. In two previous reports of white subjects with a cumulative survival analysis, it was suggested that patients with P:KD1 homozygous for the deletion allele of the angiotensin-converting enzyme (ACE) gene are at increased risk for early renal death. To confirm this hypothesis in Japanese subjects, 103 individuals with PKD were genotyped for several components of the RAS, ie, ACE insertion/deletion (I/D) polymorphism, angiotensinogen (AGT) M235T, and angiotensin II type 1 receptor (AT1) A1166C. Seventy-six of the 103 patients (73.8%) reached ESRD at an average age of 52.1 +/- 11.3 years. The frequencies of each genotype of the genes were similar to those expected from Hardy-Weinberg equilibrium. There was a tendency to an excess of patients homozygous for the D allele in patients with ESRD (DD in patients with ESRD, 11.8%; DD in patients without ESRD, 3.7%; chi-square, 1.505; P: = 0.22). Cumulative renal survival was significantly less in those with the DD genotype compared with ID/II genotypes. Estimated mean renal survival was 46.4 years (95% confidence interval, 39.5 to 53.3) in subjects with the DD genotype and 57.2 years (95% confidence interval, 54.2 to 60.2) in ID/II genotypes (chi-square, 7.76; P: = 0.0053). There was no association between age at onset of ESRD and either M235T or A1166C polymorphism. These findings suggest that Japanese patients with PKD homozygous for the D allele of the ACE gene are at increased risk for developing ESRD at an early age.
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Wadhwa R, Sugihara T, Yoshida A, Nomura H, Reddel RR, Simpson R, Maruta H, Kaul SC. Selective toxicity of MKT-077 to cancer cells is mediated by its binding to the hsp70 family protein mot-2 and reactivation of p53 function. Cancer Res 2000; 60:6818-21. [PMID: 11156371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
MKT-077, a cationic rhodacyanine dye analogue has been under preclinical cancer therapeutical trials because of its selective toxicity to cancer cells. Its cellular targets and mechanism of action remain poorly understood. Here we report that MKT-077 binds to an hsp70 family member, mortalin (mot-2), and abrogates its interactions with the tumor suppressor protein, p53. In cancer cells, but not in normal cells, MKT-077 induced release of wild-type p53 from cytoplasmically sequestered p53-mot-2 complexes and rescued its transcriptional activation function. Thus, MKT-077 may be particularly useful for therapy of cancers with wild-type p53.
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Nomura H, Miyake K, Kashiwagi S, Sugiyama T, Asaka M. A short-term eradication therapy for Helicobacter pylori acute gastritis. J Gastroenterol Hepatol 2000; 15:1377-81. [PMID: 11197046 DOI: 10.1046/j.1440-1746.2000.02228.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
BACKGROUND AND AIMS Acute gastritis, caused by an initial infection of Helicobacter pylori (H. pylori), may resolve spontaneously, but the infection sometimes becomes chronic. We examined the efficacy of a short-term H. pylori eradication therapy on acute gastritis. METHODS Among the 15 patients with hemorrhagic acute gastritis who were randomly allocated to group A (eradication therapy) or group B (Lansoprazole, LPZ), 10 of them started to receive treatment within 1 day after the disease onset. The other five patients began the eradication therapy 4-6 days after disease onset (group C). Eradication therapy consisted of a daily oral administration of each of 30 mg lansoprazole (LPZ), once a day; 400 mg clarithromycin, twice a day; 1000 mg amoxicillin, twice a day; and 300 mg rebamipide, three times a day, for one week. If the endoscopy was normal, medication was stopped for the following 4 weeks before gastric endoscopy was performed again in order to assess H. pylori eradication. RESULTS All group A patients were cured after the 1-week treatment and therefore, they became H. pylori negative. Group B and C patients had erosions or ulcers after the 1-week treatment and so received an additional 3-week administration of LPZ. Four weeks later, their gastritis was cured and except for one group B patient, they became H. pylori-negative. CONCLUSION In patients with acute gastritis, caused by an initial H. pylori infection, eradication therapy was efficacious in achieving early healing. This therapy should be started as soon as possible after disease onset.
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Nomura H, Tazawa M, Kuroda R, Shiraishi H, Sumi-Ichinose C, Matsui S, Ohtsuki M, Hagino Y, Nomura T. Effects of sulfhydryl reagents on nitric oxide release from a nitric oxide donor NOR 3 in the presence of rat hepatocytes. PHARMACOLOGY & TOXICOLOGY 2000; 87:246-8. [PMID: 11129506 DOI: 10.1034/j.1600-0773.2000.d01-82.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Nomura H, Shimokata H, Niino N, Ando F, Sugita J, Miyake Y. Estimation of anterior nucleus of lens by Scheimpflug image before and after pupil dilatation. Jpn J Ophthalmol 2000; 44:682-5. [PMID: 11094188 DOI: 10.1016/s0021-5155(00)00287-2] [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] [Indexed: 11/22/2022]
Abstract
PURPOSE To compare the accuracy of lens transparency evaluations by Scheimpflug image in the anterior nucleus of the lens before and after pupil dilatation. METHODS Scheimpflug lens images were recorded in 70 eyes of 38 subjects (age: 28-75 years) before and after pupil dilatation, and light scattering intensity measurements before and after dilatation were compared. RESULTS There was a significant positive correlation between the light scattering intensity before and after dilatation at the anterior cortex, anterior nucleus, and central clear zone of the lens (r > 0.9, P <.0001). CONCLUSIONS It is possible to estimate the transparency in the anterior nucleus of the lens from the Scheimpflug image without pupil dilatation. If nuclear type cataracts are regarded as a structural marker of aging in epidemiological studies, measuring the light scattering intensity in the anterior nucleus of the lens without dilatation seems to be a safe, useful, and quantitative method.
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Haji S, Nomura H, Yasuda K, Hashimoto N, Ohyanagi H. Combining the selective arterial calcium injection test and intraoperative blood glucose monitoring for multiple insulinomas: report of two cases. Surg Today 2000; 30:537-40. [PMID: 10883467 DOI: 10.1007/s005950070123] [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] [Indexed: 02/07/2023]
Abstract
To date, no precise methods of preoperatively localizing multiple insulinomas or intraoperatively confirming their complete removal have been established. We describe herein the effectiveness of combining the selective arterial calcium injection (SACI) test to locate tumors preoperatively, with intraoperative continuous blood glucose monitoring (IOBGM) to confirm their complete removal. During the 8-year period from 1990 to 1997, we experienced two patients with multiple insulinomas. The first patient required resection of a residual tumor in the remnant pancreas for persistent hyperinsulinemia after a distal pancreatectomy performed under conventional diagnostic procedures. In the second patient, a SACI test was performed in addition to other diagnostic imaging procedures, and while computed tomography scan, endoscopic ultrasonography, and arteriography demonstrated multiple tumors in the body and tail of pancreas, the SACI test suggested that there were also tumors in the head of pancreas. Intraoperative ultrasonography showed a tumor measuring 5 mm in diameter on the surface of the head of the pancreas, apart from the multiple tumors in the body and tail of the pancreas. Complete removal of all tumors was assessed by the hyperglycemic rebound after resection of the tumors, determined by IOBGM. Based upon our experience, we believe that the SACI test and IOBGM are helpful for establishing precise localization and achieving complete removal of multiple insulinomas.
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Nomura H, Koda S, Matsuoka T, Hiyama T, Shibata R, Kato S. Study of Salt Effects on the Micelle-Monomer Exchange Process of Octyl-, Decyl-, and Dodecyltrimethylammonium Bromide in Aqueous Solutions by Means of Ultrasonic Relaxation Spectroscopy. J Colloid Interface Sci 2000; 230:22-28. [PMID: 10998284 DOI: 10.1006/jcis.2000.7067] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The effects of added salt on the micelle-monomer exchange process of octyl- and decyltrimethylammonium bromide were investigated by means of ultrasonic relaxation techniques. Using the Aniansson-Wall model, the micellar distribution width sigma and the dissociation rate constant k(-1) of the micelle-monomer exchange process were determined as functions of carbon number and of added salt concentration in aqueous solutions of a series of tetraalkylammonium bromide-NaBr systems and discussed on the basis of the Aniansson-Wall-Teubner model. From the rate constant of the micelle-monomer exchange process, the total energy change for the transfer of the alkyl chain of the surfactant ion from the interior of the micelle to a position where its terminal methyl groups is at the surface of the micelles was estimated and compared with those calculated by the Gouy-Chapmann model of the electric double-layer theory. Copyright 2000 Academic Press.
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Nomura H, Haji S, Kuroda D, Yasuda K, Ohyanagi H, Kudo M. Laparoscopic splenopexy for adult wandering spleen: sandwich method with two sheets of absorbable knitted mesh. Surg Laparosc Endosc Percutan Tech 2000; 10:332-4. [PMID: 11083221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Wandering spleen is a rare entity with a constant danger of splenic torsion leading to splenomegaly and infarction, which requires surgery. The authors describe a 30-year-old woman with intermittent left hypochondralgia and back pain with wandering spleen, who was successfully treated with a new method of laparoscopic splenopexy. In this procedure, two sheets of absorbable knitted mesh were used to sandwich the detorsed spleen. The procedure is feasible and less invasive, without impaired splenic function, and is applicable even for adult splenomegalic wandering spleen.
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Naito M, Nomura H, Iguchi A. [Why do medical students not have a geriatrics textbook?]. Nihon Ronen Igakkai Zasshi 2000; 37:734-8. [PMID: 11109845 DOI: 10.3143/geriatrics.37.734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
To study the opinions of medical students on textbooks of geriatrics, we made a questionnaire for 5th-year medical students. All students had their own textbook (s) of internal medicine, and nearly half of the students had textbook (s) of physical examination. However, only 3.6% of students had their own textbook of geriatrics. The reasons for not having a textbook of geriatrics were as follows: 1) no understanding which textbook is better (59.1%), 2) no need to have a textbook (15.5%), 3) no appropriate textbooks (4.1%), and 4) others (17.6%). The most important point for choosing a textbook was as follows: 1) information from friends or seniors (38.9%), 2) looking by oneself (47.7%), 3) recommendation of a teacher (9.8%), and 4) others (3.6%).
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Kato Y, Wu X, Naito M, Nomura H, Kitamoto N, Osawa T. Immunochemical detection of protein dityrosine in atherosclerotic lesion of apo-E-deficient mice using a novel monoclonal antibody. Biochem Biophys Res Commun 2000; 275:11-5. [PMID: 10944432 DOI: 10.1006/bbrc.2000.3265] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Dityrosine is one of the specific biomarkers for proteinoxidation. We prepared an antibody specific for proteindityrosine using a dimer of 3-p-(hydroxyphenyl)propionic acid (di-HP) as a hapten. Three clones (A8, G6, and 1C3) were obtained, and the antibody from the A8 clone reacted with the di-HP-conjugated protein but not with a dityrosine conjugate. The others (G6 and 1C3 clones) recognized both the di-HP and dityrosine conjugates. The antibodies reacted with peptidyl dityrosine, derived from Thr-Tyr-Ser, rather than the free dityrosine. The reactivity of the latter two antibodies with lens proteins oxidized by incubation with H(2)O(2)/Cu was in good accordance with the formation of the dityrosine-like fluorescence. Using the obtained monoclonal antibody, the immunopositive staining of atherosclerotic lesions in Apo E-deficient mice was confirmed by an immunohistochemical technique.
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Mori K, Ando F, Nomura H, Sato Y, Shimokata H. Relationship between intraocular pressure and obesity in Japan. Int J Epidemiol 2000; 29:661-6. [PMID: 10922342 DOI: 10.1093/ije/29.4.661] [Citation(s) in RCA: 128] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Some cross-sectional studies have suggested that age, systolic blood pressure and obesity are positively related to intraocular pressure (IOP), but few longitudinal studies have examined this relationship. This study was carried out to evaluate the association between intraocular pressure and obesity by cross-sectional and longitudinal analyses in a large Japanese population. METHODS Data were collected from annual health examinations between 1989 and 1997 and reviewed retrospectively. Subjects of the cross-sectional analysis were 70 139 males and females aged 14-94 years. Among these subjects, 25 216 males and females who had undergone IOP measurements more than three times were analysed longitudinally. The association between IOP and obesity was examined cross-sectionally and longitudinally. RESULTS Cross-sectional analysis: The mean IOP at the last visit was 11.6 mmHg. The IOP decreased gradually with age and was significantly higher in males than in females in almost all age groups. Body mass index (BMI) significantly correlated with IOP after controlling for age, gender and blood pressure. Longitudinal analysis: There was a significant association between longitudinal change in IOP and change in weight. This relationship remained significant after controlling for initial BMI, initial blood pressure, change in blood pressure, gender and age. CONCLUSION This study showed a significant association between IOP and obesity in both cross-sectional and longitudinal analysis. These findings suggest that obesity is an independent risk factor for increase in IOP.
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Zhang Z, Lewis D, Strock C, Inesi G, Nakasako M, Nomura H, Toyoshima C. Detailed characterization of the cooperative mechanism of Ca(2+) binding and catalytic activation in the Ca(2+) transport (SERCA) ATPase. Biochemistry 2000; 39:8758-67. [PMID: 10913287 DOI: 10.1021/bi000185m] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Expression of heterologous SERCA1a ATPase in Cos-1 cells was optimized to yield levels that account for 10-15% of the microsomal protein, as revealed by protein staining on electrophoretic gels. This high level of expression significantly improved our characterization of mutants, including direct measurements of Ca(2+) binding by the ATPase in the absence of ATP, and measurements of various enzyme functions in the presence of ATP or P(i). Mutational analysis distinguished two groups of amino acids within the transmembrane domain: The first group includes Glu771 (M5), Thr799 (M6), Asp800 (M6), and Glu908 (M8), whose individual mutations totally inhibit binding of the two Ca(2+) required for activation of one ATPase molecule. The second group includes Glu309 (M4) and Asn796 (M6), whose individual or combined mutations inhibit binding of only one and the same Ca(2+). The effects of mutations of these amino acids were interpreted in the light of recent information on the ATPase high-resolution structure, explaining the mechanism of Ca(2+) binding and catalytic activation in terms of two cooperative sites. The Glu771, Thr799, and Asp800 side chains contribute prominently to site 1, together with less prominent contributions by Asn768 and Glu908. The Glu309, Asn796, and Asp800 side chains, as well as the Ala305 (and possibly Val304 and Ile307) carbonyl oxygen, contribute to site 2. Sequential binding begins with Ca(2+) occupancy of site 1, followed by transition to a conformation (E') sensitive to Ca(2+) inhibition of enzyme phosphorylation by P(i), but still unable to utilize ATP. The E' conformation accepts the second Ca(2+) on site 2, producing then a conformation (E' ') which is able to utilize ATP. Mutations of residues (Asp813 and Asp818) in the M6/M7 loop reduce Ca(2+) affinity and catalytic turnover, suggesting a strong influence of this loop on the correct positioning of the M6 helix. Mutation of Asp351 (at the catalytic site within the cytosolic domain) produces total inhibition of ATP utilization and enzyme phosphorylation by P(i), without a significant effect on Ca(2+) binding.
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Kaul SC, Sugihara T, Yoshida A, Nomura H, Wadhwa R. Gros1, a potential growth suppressor on chromosome 1: its identity to basement membrane-associated proteoglycan, leprecan. Oncogene 2000; 19:3576-83. [PMID: 10951563 DOI: 10.1038/sj.onc.1203696] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
By immunoscreening with an antibody raised against a plasma membrane protein, we have cloned a growth suppressor gene, Gros1 and assigned it to short arm of human chromosome 1. Two alternatively spliced forms of the gene encoding 84- and 41-kDa (carboxy-terminus truncated) proteins were cloned. The two transcripts, 4.4 and 2.7 kb, were expressed weakly in most of the human tissues, with a high expression of the smaller transcript in placenta, ovary and testis. Normal human fibroblasts in culture showed two transcripts, with a higher level of expression of the 4.4 kb transcript. Transformed cells on the other hand showed predominant expression of the 2.7 kb transcript. Two Gros1 transcripts were also detected in most of the mouse tissues. Stable transfection of the mouse cDNA encoding the 85-kDa protein into NIH3T3 cells resulted in their slow growth and reduced colony-forming efficiency. Stable clones expressing antisense RNA on the other hand exhibited higher colony forming efficiency. While our data implied that Gros1 is a novel growth suppressor gene on human chromosome 1, an independent study has recently characterized its rat-homolog as a leucine proline-enriched novel basement membrane-associated proteoglycan leprecan. We describe here cloning, expression and biological activity analysis implying that this novel proteoglycan is a potential growth suppressor on chromosome 1p31, frequently altered in many malignancies.
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Wiederhold ML, Harrison JL, Parker K, Nomura H. Otoliths developed in microgravity. JOURNAL OF GRAVITATIONAL PHYSIOLOGY : A JOURNAL OF THE INTERNATIONAL SOCIETY FOR GRAVITATIONAL PHYSIOLOGY 2000; 7:P39-42. [PMID: 12697538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Abstract
Little is known about mechanisms that regulate the development of the otoliths in the gravity-sensing organs. Several reported experiments suggest that the growth of the otoliths is adjusted to produce a test mass of the appropriate weight. If this is the case, larger than normal otoliths would be expected in animals reared in reduced gravity and a reduced mass, relative to 1-g controls, would be expected in animals reared at elevated g. In gastropod mollusks, the gravity-sensing organ is the statocyst, a spherical organ whose wall is made largely of sensory receptor cells with motile cilia facing the lumen. Dense statoconia in the cyst lumen interact with cilia of receptor cells at the bottom of the cyst and action potentials in their axons carry information on direction and magnitude of gravity and linear acceleration. In the marine mollusk, Aplysia californica, larvae reared at 2 to 5-g, the volume of statoconia was reduced in a graded manner, compared to 1-g control animals. In the statocyst of the fresh-water pond snail, Biomphalaria glabrata, reared in space in the Closed Equilibrated Biological Aquatic System (CEBAS), the number and total volume of statoconia was increased approximately 50%, relative to ground-reared controls. Lychakov found the utricular otolith to be 30% larger in space-reared Xenopus, whereas we found the saccular otolith to be significantly larger in newt larvae reared in space. In cichlid fish reared on a centrifuge, the saccular otolith was smaller than in 1-g controls. Here, we demonstrate that the otoliths of late-stage embryos of the swordtail fish, Xiphophorus helleri, reared in space on STS-89 and STS-90 (Neurolab) were significantly larger than those of ground-controls reared in functionally identical hardware.
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Naito M, Nomura H, Kodama M, Iguchi A, Thompson W, Smith E. Mechanisms of smooth muscle cell migration into fibrin gels. Atherosclerosis 2000. [DOI: 10.1016/s0021-9150(00)80080-5] [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: 10/18/2022]
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147
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Nomura H, Naito M, Kato Y, Iguchi A. Effects of gliclazide on low-density lipoprotein oxidazability and atherosclerosis in cholesterol-fed rabbits. Atherosclerosis 2000. [DOI: 10.1016/s0021-9150(00)81393-3] [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: 10/18/2022]
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148
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Toyoshima C, Nakasako M, Nomura H, Ogawa H. Crystal structure of the calcium pump of sarcoplasmic reticulum at 2.6 A resolution. Nature 2000; 405:647-55. [PMID: 10864315 DOI: 10.1038/35015017] [Citation(s) in RCA: 1345] [Impact Index Per Article: 56.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Calcium ATPase is a member of the P-type ATPases that transport ions across the membrane against a concentration gradient. Here we have solved the crystal structure of the calcium ATPase of skeletal muscle sarcoplasmic reticulum (SERCA1a) at 2.6 A resolution with two calcium ions bound in the transmembrane domain, which comprises ten alpha-helices. The two calcium ions are located side by side and are surrounded by four transmembrane helices, two of which are unwound for efficient coordination geometry. The cytoplasmic region consists of three well separated domains, with the phosphorylation site in the central catalytic domain and the adenosine-binding site on another domain. The phosphorylation domain has the same fold as haloacid dehalogenase. Comparison with a low-resolution electron density map of the enzyme in the absence of calcium and with biochemical data suggests that large domain movements take place during active transport.
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149
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Sakurai T, Matsuoka T, Koda S, Nomura H. Acoustic characteristics of PMMA in the steady stress-strain state investigated by coherent Brillouin scattering method. J Appl Polym Sci 2000. [DOI: 10.1002/(sici)1097-4628(20000509)76:6<978::aid-app25>3.0.co;2-n] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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150
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Hashimoto N, Fujiwara H, Nomura H, Ohyanagi H. In vivo evaluation of long-term patency of pancreaticoenterostomy after Whipple operation. HEPATO-GASTROENTEROLOGY 2000; 47:866-8. [PMID: 10919049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
BACKGROUND/AIMS The aim of this study was to examine the long-term patency of pancreaticoenterostomy in vivo. METHODOLOGY Evaluation of the patency of the pancreaticoenterostomy was conducted in 12 patients who had undergone the Whipple procedure. After intravenous infusion of secretin (1 microgram/kg), the diameter of the pancreatic duct was taken at 1, 3, 5, 15, 20 and 25 min by means of ultrasonography. We estimated the degree of anastomotic stricture by the maximal dilatation ratio [MDR: Maximal value (Dmax)/basal value (D0)]. The patients underwent pancreatic exocrine function tests before and 1-2 years after surgery. RESULTS Maximal ductal dilatation was noted from 3 min of 15 min after secretin infusion, thereafter ductal diameter gradually diminished and returned to its basal value at 25 min. Maximal dilatation ratio ranged from 1.3-2.5, 1.7 +/- 0.12. There was a good negative relationship between the maximal dilatation ratio and pancreatic exocrine function. Based on the result of chi 2 analysis, we judged anastomotic stricture to be present in 2 patients with maximal dilatation ratio above 2.0. In these 2 patients, preoperative pancreatic exocrine function recoveries were 69 and 48%, while postoperative pancreatic exocrine function recoveries were 13.8 and 18%, respectively. In the other 10 patients, there was no difference between preoperative and postoperative value of pancreatic exocrine function. CONCLUSIONS The present method permits safe and non-invasive evaluation of the patency of pancreaticoenterostomy.
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