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Ohno Y, Nakatani M, Ito T, Matsui Y, Ando K, Suda Y, Ohashi K, Yokoyama S, Goto K. Activation of Lactate Receptor Positively Regulates Skeletal Muscle Mass in Mice. Physiol Res 2023; 72:465-473. [PMID: 37795889 PMCID: PMC10634564 DOI: 10.33549/physiolres.935004] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 05/23/2023] [Indexed: 01/05/2024] Open
Abstract
G protein-coupled receptor 81 (GPR81), a selective receptor for lactate, expresses in skeletal muscle cells, but the physiological role of GPR81 in skeletal muscle has not been fully elucidated. As it has been reported that the lactate administration induces muscle hypertrophy, the stimulation of GPR81 has been suggested to mediate muscle hypertrophy. To clarify the contribution of GPR81 activation in skeletal muscle hypertrophy, in the present study, we investigated the effect of GPR81 agonist administration on skeletal muscle mass in mice. Male C57BL/6J mice were randomly divided into control group and GPR81 agonist-administered group that received oral administration of the specific GPR81 agonist 3-Chloro-5-hydroxybenzoic acid (CHBA). In both fast-twitch plantaris and slow-twitch soleus muscles of mice, the protein expression of GPR81 was observed. Oral administration of CHBA to mice significantly increased absolute muscle weight and muscle weight relative to body weight in the two muscles. Moreover, both absolute and relative muscle protein content in the two muscles were significantly increased by CHBA administration. CHBA administration also significantly upregulated the phosphorylation level of p42/44 extracellular signal-regulated kinase-1/2 (ERK1/2) and p90 ribosomal S6 kinase (p90RSK). These observations suggest that activation of GRP81 stimulates increased the mass of two types of skeletal muscle in mice in vivo. Lactate receptor GPR81 may positively affect skeletal muscle mass through activation of ERK pathway.
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Affiliation(s)
- Y Ohno
- Faculty of Rehabilitation and Care, Seijoh University, Tokai, Japan.
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2
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Onishi T, Nakatani M, Matsumoto R, Shibahara T, Sekito S, Kajiwara S, Okamoto T. A prospective randomized study comparing short-time with long-time continuous saline bladder irrigation after transurethral resection in non-muscular invasive bladder cancer. Eur Urol 2023. [DOI: 10.1016/s0302-2838(23)00756-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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Nakazawa R, Azuma N, Suzuki M, Nakatani M, Nankou T, Furuyoshi S, Yasuda A, Takata S, Tani N, Kobayashi F. A New Treatment for Dialysis-Related Amyloidosis with β 2-Microglobulin Adsorbent Column. Int J Artif Organs 2018. [DOI: 10.1177/039139889301601207] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Dialysis-related amyloidosis (DRA) is characterized by the presence of β 2-microglobulin (β 2-m) in the plasma. In order to eliminate β 2-m from the circulating blood, the β 2-m selective adsorbent for direct hemoperfusion (DHP) was developed. A DHP column (BM-01), containing 350 ml of the adsorbent, was subjected to clinical trials. The column was connected with a PAN (AN69) membrane dialyzer in series and used 3 times a week for 1 week (11 patients), 4 weeks (5 patients), 6 months (1 patient) and 12 months (2 patients). The percent reduction (%) of β 2-m was for 16 patients (for 1 or 4 weeks), more than 65, and for 3 patients (for more than 6 months), 76.5 ± 4.9, 73.5 ± 5.7, 72.2 ± 6.2. At the end of each session, β 2-m plasma levels were found to be below 10 mg/L, with 3.4 mg/L being the lowest. The total amounts of β 2-m removed were 172.5 ± 22.3, 257.0 ± 75.6, 157.6 ± 32.2 and 429.8 mg/session at max. Two out of these three patients had a favorable effect on joint symptoms and ocular fundus. It can be concluded that this selective adsorption therapy may delay the progression of DRA, and is worth considering for wide application.
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Affiliation(s)
| | - N. Azuma
- Tokatsu Clinic Hospital, Matsudo
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Nakatani M, Matsumoto R, Kobayshi K, Hitomi T, Inouchi M, Matsuhashi M, Kinoshita M, Kikuchi T, Yoshida K, Kunieda T, Takahashi R, Hattori N, Ikeda A. Inhibitory effects of electric cortical stimulation on interictal epileptiform discharges in human epileptic focus. J Neurol Sci 2017. [DOI: 10.1016/j.jns.2017.08.3774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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5
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Nakatani M, Migita K, Matsumoto S, Wakatsuki K, Ito M, Nakade H, Kunishige T, Kitano M, Kanehiro H. Prognostic significance of the prognostic nutritional index in esophageal cancer patients undergoing neoadjuvant chemotherapy. Dis Esophagus 2017; 30:1-7. [PMID: 28575242 DOI: 10.1093/dote/dox020] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Accepted: 03/06/2017] [Indexed: 12/11/2022]
Abstract
Nutritional status is one of the most important issues faced by cancer patients. Several studies have shown that a low preoperative nutritional status is associated with a worse prognosis in patients with various types of cancer, including esophageal cancer (EC). Recently, neoadjuvant chemotherapy (NAC) and/or radiotherapy have been accepted as the standard treatment for resectable advanced EC. However, NAC has the potential to deteriorate the nutritional status of a patient. This study aimed to evaluate the prognostic significance of the nutritional status for EC patients who underwent NAC. We retrospectively reviewed 66 squamous cell EC patients who underwent NAC consisting of docetaxel, cisplatin, and 5-fluorouracil followed by subtotal esophagectomy at Nara Medical University Hospital between January 2009 and August 2015. To assess the patients' nutritional status, the prognostic nutritional index (PNI) before commencing NAC and prior to the operation was calculated as 10 × serum albumin (g/dl) + 0.005 × total lymphocyte count in the peripheral blood (per mm3). The cutoff value of the PNI was set at 45. A multivariable analysis was performed to identify prognostic factors for overall survival (OS) and relapse-free survival (RFS). The mean pre-NAC and preoperative PNI were 50.2 ± 5.7 and 48.1 ± 4.7, respectively (P = 0.005). The PNI decreased following NAC in 44 (66.7%) patients. Before initiating NAC, 9 (13.6%) patients had a low PNI, and 12 (18.2%) patients had a low PNI prior to the operation. The pre-NAC PNI and preoperative PNI were significantly associated with the OS (P = 0.013 and P = 0.004, respectively) and RFS (P = 0.036 and P = 0.005, respectively) rates. The multivariable analysis identified the preoperative PNI as an independent prognostic factor for poor OS and RFS, although the pre-NAC PNI was not an independent predictor. Our results suggest that the preoperative PNI is a useful marker for predicting the long-term outcomes of EC patients undergoing NAC and subsequent subtotal esophagectomy. Therefore, patients with a low preoperative nutritional status may be at a higher risk of EC recurrence.
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Affiliation(s)
- M Nakatani
- Department of Surgery, Nara Medical University, Nara, Japan
| | - K Migita
- Department of Surgery, Nara Medical University, Nara, Japan
| | - S Matsumoto
- Department of Surgery, Nara Medical University, Nara, Japan
| | - K Wakatsuki
- Department of Surgery, Nara Medical University, Nara, Japan
| | - M Ito
- Department of Surgery, Nara Medical University, Nara, Japan
| | - H Nakade
- Department of Surgery, Nara Medical University, Nara, Japan
| | - T Kunishige
- Department of Surgery, Nara Medical University, Nara, Japan
| | - M Kitano
- Department of Surgery, Nara Medical University, Nara, Japan
| | - H Kanehiro
- Department of Surgery, Nara Medical University, Nara, Japan
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Usui S, Maeo S, Tayashiki K, Nakatani M, Kanehisa H. Low-load Slow Movement Squat Training Increases Muscle Size and Strength but Not Power. Int J Sports Med 2015; 37:305-12. [PMID: 26667928 DOI: 10.1055/s-0035-1564255] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
We tested a hypothesis that low-load squat training with slow movement and tonic force generation (LST) would increase muscle size and strength but not necessarily power. Healthy young men were assigned to LST [50% one-repetition maximum (1-RM) load, 3 s for lowering/lifting without pause: n=9] or low-load normal speed (LN: 50% 1-RM load, 1 s for lowering/lifting with 1-s pause; n=7) groups. Both groups underwent an 8-week squat training program (10 repetitions/set, 3 sets/day, and 3 days/week) using the assigned methods. Before and after the intervention, quadriceps femoris muscle thickness, maximal torque during isometric hip extension and knee extension, 1-RM squat, lifting power from squatting position and rate of electromyography rise (RER) in knee extensors during the task, leg extension power and vertical jump height were measured. After the intervention, the LN group showed no changes in all the variables. The LST group significantly (P<0.05) increased muscle thickness (6-10%), isometric hip extension torque (18%) and 1-RM squat (10%), but not isometric knee extension torque, lifting power and RER, leg extension power and vertical jump height. These results suggest that LST can increase muscle size and task-related strength, but has little effect on power production during dynamic explosive movements.
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Affiliation(s)
- S Usui
- Sports and Life Science, National Institute of Fitness and Sports in Kanoya
| | - S Maeo
- Faculty of Sport Sciences, Waseda University, Tokorozawa, Japan
| | - K Tayashiki
- Sports and Life Science, National Institute of Fitness and Sports in Kanoya
| | - M Nakatani
- Sports and Life Science, National Institute of Fitness and Sports in Kanoya
| | - H Kanehisa
- Sports and Life Science, National Institute of Fitness and Sports in Kanoya
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Kariya S, Nakatani M, Yoshida R, Ueno Y, Komemushi A, Tanigawa N. REPEATED INTRANODAL LYMPHANGIOGRAPHY FOR THE TREATMENT OF LYMPHATIC LEAKAGE. Lymphology 2015; 48:59-63. [PMID: 26714370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Treatment of patients with chylous or non-chylous lymphatic leakage can be difficult. An approach using therapeutic lymphangiography can reduce the lymphatic leakage, but it seldom stops the leakage immediately and subsequent conservative treatment is necessary. We report three cases in which intranodal lymphangiography was performed multiple times to inhibit lymphatic leakage. In each case, the lymph node was punctured under ultrasound guidance using a 23-gauge needle and lipiodol was injected manually at a rate of 1 ml/3 min. The procedure was repeated twice in two cases of gastrointestinal carcinoma and four times in one case of lymphoma. In all three cases, the postoperative lymphatic leakage stopped after the repeated intranodal lymphangiography.
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Uezumi A, Fukada S, Yamamoto N, Ikemoto-Uezumi M, Nakatani M, Morita M, Yamaguchi A, Yamada H, Nishino I, Hamada Y, Tsuchida K. Identification and characterization of PDGFRα+ mesenchymal progenitors in human skeletal muscle. Cell Death Dis 2014; 5:e1186. [PMID: 24743741 PMCID: PMC4001314 DOI: 10.1038/cddis.2014.161] [Citation(s) in RCA: 190] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Revised: 03/03/2014] [Accepted: 03/04/2014] [Indexed: 02/07/2023]
Abstract
Fatty and fibrous connective tissue formation is a hallmark of diseased skeletal muscle and deteriorates muscle function. We previously identified non-myogenic mesenchymal progenitors that contribute to adipogenesis and fibrogenesis in mouse skeletal muscle. In this study, we report the identification and characterization of a human counterpart to these progenitors. By using PDGFRα as a specific marker, mesenchymal progenitors can be identified in the interstitium and isolated from human skeletal muscle. PDGFRα+ cells represent a cell population distinct from CD56+ myogenic cells, and adipogenic and fibrogenic potentials were highly enriched in the PDGFRα+ population. Activation of PDGFRα stimulates proliferation of PDGFRα+ cells through PI3K-Akt and MEK2-MAPK signaling pathways, and aberrant accumulation of PDGFRα+ cells was conspicuous in muscles of patients with both genetic and non-genetic muscle diseases. Our results revealed the pathological relevance of PDGFRα+ mesenchymal progenitors to human muscle diseases and provide a basis for developing therapeutic strategy to treat muscle diseases.
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Affiliation(s)
- A Uezumi
- Division for Therapies against Intractable Diseases, Institute for Comprehensive Medical Science, Fujita Health University, 1-98 Dengakugakubo, Kutsukake, Toyoake, Aichi 470-1192, Japan
| | - S Fukada
- Department of Immunology, Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - N Yamamoto
- Laboratory of Molecular Biology and Histochemistry, Fujita Health University, Aichi, Japan
| | - M Ikemoto-Uezumi
- Department of Regenerative Medicine, National Institute for Longevity Sciences, National Center for Geriatrics and Gerontology, 35 Gengo, Morioka, Obu, Aichi 474-8511, Japan
| | - M Nakatani
- Division for Therapies against Intractable Diseases, Institute for Comprehensive Medical Science, Fujita Health University, 1-98 Dengakugakubo, Kutsukake, Toyoake, Aichi 470-1192, Japan
| | - M Morita
- Department of Orthopaedic Surgery, Fujita Health University, Aichi, Japan
| | - A Yamaguchi
- Department of Orthopaedic Surgery, Fujita Health University, Aichi, Japan
| | - H Yamada
- Department of Orthopaedic Surgery, Fujita Health University, Aichi, Japan
| | - I Nishino
- Department of Neuromuscular Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-higashi, Kodaira, Tokyo 187-8502, Japan
| | - Y Hamada
- Department of Orthopedics, Tokushima Prefectural Central Hospital, 1-10-3 Kuramoto, Tokushima 770-8539, Japan
| | - K Tsuchida
- Division for Therapies against Intractable Diseases, Institute for Comprehensive Medical Science, Fujita Health University, 1-98 Dengakugakubo, Kutsukake, Toyoake, Aichi 470-1192, Japan
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Suzuki S, Komemushi A, Sano A, Kariya S, Kanno S, Nakatani M, Yoshida R, Kono Y, Tanigawa N. Short term efficacy and safety of balloon-occluded retrograde transvenous obliteration of portosystemic shunt in patients with hepatic encephalopathy. J Vasc Interv Radiol 2014. [DOI: 10.1016/j.jvir.2013.12.332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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10
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Yoshida R, Kariya S, Nakatani M, Kono Y, Komemushi A, Tanigawa N. Renal volume reduction by transcatheter renal artery embolization with N-butyl cyanoacrylate for symptomatic polycystic kidney disease. J Vasc Interv Radiol 2014. [DOI: 10.1016/j.jvir.2013.12.142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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Kariya S, Komemushi A, Nakatani M, Yoshida R, Sawada S, Tanigawa N. Re: CO2 microbubble contrast enhancement in x-ray angiography. A reply. Clin Radiol 2013; 68:1180. [DOI: 10.1016/j.crad.2013.06.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Accepted: 06/03/2013] [Indexed: 11/26/2022]
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Nakatani M, Fukuda T, Sasamoto H, Arakawa N, Otaka H, Kawasoe T, Omata S. Relationship between perceived softness of bilayered skin models and their mechanical properties measured with a dual-sensor probe. Int J Cosmet Sci 2012; 35:84-8. [DOI: 10.1111/ics.12008] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2012] [Accepted: 09/03/2012] [Indexed: 11/30/2022]
Affiliation(s)
- M. Nakatani
- Shiseido Research Center; 2-12-1, Fukuura, Kanazawa-ku, Yokohama 236-8643; Japan
| | - T. Fukuda
- Department of Electrical and Electronics Engineering NEWCAT Institute; Nihon University College of Engineering; 1 Nakagawara, Tokusada, Tamura, Koriyama, Fukushima; 963-8642 Japan
| | - H. Sasamoto
- Shiseido Research Center; 2-12-1, Fukuura, Kanazawa-ku, Yokohama 236-8643; Japan
| | - N. Arakawa
- Shiseido Research Center; 2-12-1, Fukuura, Kanazawa-ku, Yokohama 236-8643; Japan
| | - H. Otaka
- Shiseido Research Center; 2-12-1, Fukuura, Kanazawa-ku, Yokohama 236-8643; Japan
| | - T. Kawasoe
- Shiseido Research Center; 2-12-1, Fukuura, Kanazawa-ku, Yokohama 236-8643; Japan
| | - S. Omata
- Department of Electrical and Electronics Engineering NEWCAT Institute; Nihon University College of Engineering; 1 Nakagawara, Tokusada, Tamura, Koriyama, Fukushima; 963-8642 Japan
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Kariya S, Komemushi A, Nakatani M, Yoshida R, Sawada S, Tanigawa N. CO2 microbubble contrast enhancement in x-ray angiography. Clin Radiol 2012; 68:346-51. [PMID: 22981730 DOI: 10.1016/j.crad.2012.08.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2012] [Revised: 07/26/2012] [Accepted: 08/06/2012] [Indexed: 12/23/2022]
Abstract
AIM To demonstrate that carbon dioxide (CO2) microbubble contrast enhancement depicts blood vessels when used for x-ray examinations. MATERIALS AND METHODS Microbubbles were generated by cavitation of physiological saline to which CO2 gas had been added using an ejector-type microbubble generator. The input pressure values for CO2 gas and physiological saline that produced a large quantity of CO2 microbubbles were obtained in a phantom. In an animal study, angiography was performed in three swine using three types of contrast: CO2 microbubbles, conventional CO2 gas, and iodinated contrast medium. For CO2 microbubble contrast enhancement, physiological saline, and CO2 gas were supplied at the input pressures calculated in the phantom experiment. Regions of interest were set in the abdominal aorta, external iliac arteries, and background. The difference in digital values between each artery and the background was calculated. RESULTS The input pressures obtained in the phantom experiment were 0.16 MPa for physiological saline and 0.5 MPa for CO2 gas, with physiological saline input volume being 8.1 ml/s. Three interventional radiologists all evaluated the depictions of all arteries as "present" in the CO2 microbubble contrast enhancement, conventional CO2 contrast enhancement, and iodinated contrast enhancement performed in three swine. Digital values for all vessels with microbubble CO2 contrast enhancement were higher than background values. CONCLUSIONS In x-ray angiography, blood vessels can be depicted by CO2 microbubble contrast enhancement, in which a large quantity of CO2 microbubbles is generated within blood vessels.
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Affiliation(s)
- S Kariya
- Department of Radiology, Kansai Medical University, Hirakata, Osaka, Japan.
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Nagata K, Nakatani M, Yoshida S. A revised rate- and state-dependent friction law obtained by constraining constitutive and evolution laws separately with laboratory data. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2011jb008818] [Citation(s) in RCA: 122] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Tanigawa N, Kariya S, Tokuda T, Nakatani M, Yagi R, Komemushi A, Sawada S. Abstract No. 14: Prospective analysis of respiratory function following percutaneous vertebroplasty for osteoporotic compression fractures. J Vasc Interv Radiol 2010. [DOI: 10.1016/j.jvir.2009.12.156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Abstract
The transforming growth factor-beta (TGF-beta) superfamily includes TGF-betas, activin, myostatin and bone morphogenetic proteins. Misregulation of the activity of TGF-beta family members is involved in pathogenesis of cancer, muscular dystrophy, obesity and bone and tooth remodeling. Natural inhibitors for the TGF-beta superfamily regulate fine-tuning of activity of TGF-beta family in vivo. In addition to natural inhibitors for the TGF-beta family, soluble forms of receptors for the TGF-beta family, blocking monoclonal antibodies and small chemical TGF-beta inhibitors have been developed. In this review, we summarize recent advances in our understanding of inhibitors for the TGF-beta superfamily and their medical applications.
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Affiliation(s)
- K Tsuchida
- Division for Therapies against Intractable Diseases, Institute for Comprehensive Medical Science, Fujita Health University, Toyoake, Aichi 470-1192, Japan.
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Seki T, Hinohara Y, Taki C, Nakatani M, Ozawa M, Nishimura S, Takaki A, Itho H, Takenoya F, Shioda S. PACAP Stimulates the Release of Interleukin-6 in Cultured Rat Muller Cells. Ann N Y Acad Sci 2006; 1070:535-9. [PMID: 16888221 DOI: 10.1196/annals.1317.043] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We have investigated the in vivo effect of PACAP on rat Müller cells that are the predominant glial element in the retina. Müller cells were treated with PACAP38, either alone or in the presence of the PACAP-selective antagonist, PACAP6-38. Cellular proliferation was determined by measuring the incorporation of bromodeoxyuridine, while interleukin-6 (IL-6) levels in the culture medium were examined using a B9 cell bioassay. In cultured rat Müller cells, the expression of PACAP receptor (PAC1-R) was assessed with immunohistochemistry using a PAC1-R-specific antiserum. PACAP stimulated IL-6 production in Müller cells at a concentration as low as 10(-12) M, which was not sufficient to induce cell proliferation. This elevation of IL-6 production was significantly inhibited by PACAP6-38. These data suggest that Müller cells are one of the target cells for PACAP, stimulating the release of IL-6, and providing a mechanism whereby PACAP exerts a significant neuroprotective effect in the retina.
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Affiliation(s)
- T Seki
- Ophthalmology, Kozawa Eye Hospital Eye Research Center, 2-2-11 Gokencho, Mito, Ibaraki 310-0063, Japan.
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Kawaguchi T, Nakatani M, Kawano T. Study of Dural Arteriovenous Fistula Drains into Leptomeningeal Vein without Sinus Interposition. Interv Neuroradiol 2004; 10 Suppl 1:127-34. [PMID: 20587288 DOI: 10.1177/15910199040100s122] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2004] [Accepted: 01/20/2004] [Indexed: 11/16/2022] Open
Abstract
SUMMARY We evaluated dural arteriovenous fistulas (DAVF) drains into leptomeningeal vein (LMV) without the venous sinus interposition. This type of DAVF contained the extra-sinusal type DAVF and the DAVF with so-called pure leptomeningeal venous drainage (PLMVD).We studied 15 patients with DAVF that flows into LMVD without passing into the sinus. The subjects were 5 patients with DAVF in the anterior cranial fossa, 2 with DAVF in the tentorium cerebelli, and 3 with DAVF in the craniocervical junction as extra-sinusal type DAVF and 3 with DAVF in the transverse sigmoid sinus and 2 with DAVF in the superior sagittal sinus as DAVF with PLMVD. This type appears to take a very aggressive course. The arterial pressure of the shunt is directly applied to LMV, which causes bending and winding of the vein, eventually varices, inducing intracranial haemorrhage or venous ischemia in the LMV reflux area. Emergency treatment should be performed as soon as possible. Although it is recognized that interruption of the draining vein is very effective, treatment methods such as TAE, direct surgery, and g knife treatment, or their combinations should be carefully chosen for each case.
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Affiliation(s)
- T Kawaguchi
- Department of Neurosurgery, Hakodate Kyouaikai Hospital, Kasuga; Japan
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Shibata M, Suzuki H, Nakatani M, Koba S, Geshi E, Katagiri T, Takeyama Y. The involvement of vascular endothelial growth factor and flt-1 in the process of neointimal proliferation in pig coronary arteries following stent implantation. Histochem Cell Biol 2001; 116:471-81. [PMID: 11810189 DOI: 10.1007/s00418-001-0336-4] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/21/2001] [Indexed: 11/30/2022]
Abstract
To clarify the role of vascular endothelial growth factor (VEGF) in the process of restenosis, a Palmaz-Schatz stent was implanted in the left anterior descending coronary artery of male pigs at 2 weeks after balloon injury (balloon/artery ratio 1.2:1). The animals were euthanized at 1, 2, and 4 weeks after stenting, and western blot and immunohistochemical analysis were performed using VEGF, fms-like tyrosine kinase (flt)-1, and platelet-derived growth factor (PDGF) antibodies. The expressions of VEGF and flt-1 protein in the neointima were observed as early as 1 week after stenting and remained for up to 4 weeks, while re-endothelialization was complete at 2 weeks. These protein expressions were demonstrated in proliferated smooth muscle cells throughout the entire period after stenting and, in addition, they were observed in the macrophages and endothelial cells of microvessels around stent struts at 4 weeks. The expression pattern of VEGF corresponded with that of PDGF, a growth factor well-known to induce neointimal proliferation. The cell proliferative activity, measured by the proliferating cell nuclear antigen index, around the struts remained high until 4 weeks after stenting, while that in the other areas declined at 4 weeks. These results suggest that VEGF is involved in the process of restenosis not only through its angiogenic properties and induction of monocyte chemotaxis, but also by a synergistic effect with PDGF.
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MESH Headings
- Animals
- Blotting, Western
- Cell Count
- Cell Division
- Coronary Restenosis/metabolism
- Coronary Restenosis/pathology
- Coronary Vessels/metabolism
- Coronary Vessels/pathology
- Coronary Vessels/surgery
- Endothelial Growth Factors/metabolism
- Endothelium, Vascular/metabolism
- Endothelium, Vascular/pathology
- Extracellular Matrix Proteins/metabolism
- Fluorescent Antibody Technique, Indirect
- Immunoenzyme Techniques
- Lymphokines/metabolism
- Macrophages/metabolism
- Macrophages/pathology
- Male
- Monocytes/metabolism
- Monocytes/pathology
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/pathology
- Neovascularization, Pathologic/metabolism
- Neovascularization, Pathologic/pathology
- Platelet-Derived Growth Factor/metabolism
- Proliferating Cell Nuclear Antigen/metabolism
- Stents
- Swine
- Tunica Intima/metabolism
- Tunica Intima/pathology
- Vascular Endothelial Growth Factor A
- Vascular Endothelial Growth Factors
- von Willebrand Factor/metabolism
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Affiliation(s)
- M Shibata
- Third Department of Internal Medicine, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8666, Japan.
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23
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Abstract
Two segatane diterpenoids containing a bicyclic [4,3,1] ring system were isolated, together with 11 known diterpenoids, four segetanes, five jatrophanes and two paralianes, from the aerial parts of Euphorbia paralias. The structures of the new compounds were established by spectroscopic means, including by 2D NMR and CD spectroscopic analyses. The antifeedant and antiviral activities of the isolated compounds are also described.
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Affiliation(s)
- S A Abdelgaleil
- Department of Pesticide Chemistry, Faculty of Agriculture, Alexandria University, Alexandria, Egypt
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24
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Yorozuya M, Takeyama Y, Iso Y, Shibata M, Nakatani M, Koba S, Suzuki H, Murakami M, Katagiri T. [Morphological and histological studies of in-stent restenosis in seven types of stents implanted in porcine coronary arteries]. J Cardiol 2001; 38:273-80. [PMID: 11729727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
OBJECTIVES Differences in the mechanism of restenosis after stenting between coil and tubular stents were examined in porcine coronary arteries using histological and immunohistochemical methods. METHODS Twenty-four pigs underwent balloon-induced injury in the left anterior descending coronary artery. Two weeks later, seven different stents clinically available in Japan (Coil stents: GR I, GR II, Wiktor, Cordis; Tubular stents: gfx, Multilink, Palmaz-Schatz) were implanted in the injured site. Four weeks after the stent implantation, the pigs were sacrificed for histological examination and for morphometrical analysis of the lumen, neointima, media and adventitia. Immunohistochemical studies using anti-proliferating cell nuclear antigen (PCNA), anti-alpha-smooth muscle actin and anti-macrophage antibody were also performed. RESULTS The coil stents formed eccentric, and the tubular stents formed concentric neointimal proliferation. Although there was no difference in the area of neointima between the stents, the area of lumen in the tubular stents was bigger than that in the coil stents (p < 0.01), because the vascular area was bigger in the tubular stents (p < 0.05). Immunohistochemical examination found many PCNA-positive cells in the proliferated neointima, especially in the area around the stent strut. Many of these cells around the stent strut were positively stained by anti-macrophage antibody. Other cells positively stained for PCNA were confirmed as smooth muscle cells. CONCLUSIONS Tubular stents maintained a wider lumen than coil stents, because negative remodeling after stenting was less in the tubular stents. Implantation of stents with less negative remodeling is very important to prevent restenosis after stenting.
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Affiliation(s)
- M Yorozuya
- Third Department of Internal Medicine, Showa University School of Medicine, Hatanodai 1-5-8, Shinagawa-ku, Tokyo 142-8666
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25
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Nakatani M, Abdelgaleil SA, Kurawaki J, Okamura H, Iwagawa T, Doe M. Antifeedant rings B and D opened limonoids from Khaya senegalensis. J Nat Prod 2001; 64:1261-1265. [PMID: 11678647 DOI: 10.1021/np010082k] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Three new rings B and D opened limonoids, two mexicanolides named khayanone (1) and 2-hydroxyseneganolide (2) and one rearranged phragmalin limonoid of 1-O-acetylkhayanolide A (3), were isolated together with six known B,D-seco compounds from the acetone extract of the stem bark of Khaya senegalensis. Structures of new compounds were elucidated by spectroscopic means, and the absolute stereochemistry of 1 was established by CD study of the dibenzoate derivative. The insect antifeedant and antiviral activities of the new compounds were also determined.
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Affiliation(s)
- M Nakatani
- Department of Chemistry and Bioscience, Faculty of Science, Kagoshima University, 1-21-35 Korimoto, Kagoshima 890-0065, Japan.
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26
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Katoh T, Nakatani M, Shikita S, Sampe R, Ishiwata A, Ohmori O, Nakamura M, Terashima S. Studies toward the total synthesis of popolohuanone E: enantioselective synthesis of 8-O-methylpopolohuanone E. Org Lett 2001; 3:2701-4. [PMID: 11506613 DOI: 10.1021/ol016285h] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[structure: see text]. 8-O-methylpopolohuanone E (2) was synthesized in a highly convergent manner starting from the cis-fused decalin derivative accessible from the (-)-Wieland-Miescher ketone analogue. The synthetic method features a biogenetic-type annulation of the phenolic and quinone segments to regioselectively construct the central tricyclic ring system as the key step.
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Affiliation(s)
- T Katoh
- Sagami Chemical Research Center, Nishi-Ohnuma, Sagamihara, Kanagawa 229-0012, Japan.
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27
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Badaro R, Lobo I, Nakatani M, Muiños A, Netto EM, Coler RN, Reed SG. Successful use of a defined antigen/GM-CSF adjuvant vaccine to treat mucosal Leishmaniasis refractory to antimony: A case report. Braz J Infect Dis 2001; 5:223-32. [PMID: 11712967 DOI: 10.1590/s1413-86702001000400008] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Immunotherapy has been proposed as a method to treat mucosal leishmaniasis for many years, but the approach has been hampered by poor definition and variability of antigens used, and results have been inconclusive. We report here a case of antimonial-refractory mucosal leishmaniasis in a 45 year old male who was treated with three single injections (one per month) with a cocktail of four Leishmania recombinant antigens selected after documented hypo-responsiveness of the patient to these antigens, plus 50 microg of GM-CSF as vaccine adjuvant. Three months after treatment, all lesions had resolved completely and the patient remains without relapse after two years. Side effects of the treatment included only moderate erythema and induration at the injection site after the second and third injections. We conclude that carefully selected microbial antigens and cytokine adjuvant can be successful as immunotherapy for patients with antimonial-refractory mucosal leishmaniasis.
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Affiliation(s)
- R Badaro
- Federal University of Bahia, Salvador, BA, Brazil.
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28
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Kojima R, Nakatani M, Shirotani T, Ikeda Y, Kuniyoshi T, Tajiri E, Furuta Y, Inatome T, Yokoyama M. [Effects of home oxygen therapy on patients with chronic heart failure]. J Cardiol 2001; 38:81-6. [PMID: 11525113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
OBJECTIVES Dyspnea on exertion and/or hypoxemia due to nocturnal respiratory disturbance may occur in patients with stable chronic congestive heart failure. Such patients with respiratory disorder during sleep have a poor prognosis. The effects of treatment with home oxygen therapy on patients with congestive heart failure are unclear when symptoms are stable at rest. This study investigated the effects of home oxygen therapy on patients with stable chronic congestive heart failure. METHODS Thirty-three patients with stable chronic congestive heart failure(New York Heart Association functional class II-IV) and hypoxemia during exercise or sleep were treated with oxygen above the level of 90% SaO2. The following factors were compared before and after home oxygen therapy: Subjective minimal capacity on exercise(metabolic equivalents: METs) before and 1 month after patients first became aware of dyspnea on effort using the specific activity scale(SAS); SaO2 at rest before and 1 month after; and frequency of admission during 1 year due to deterioration of heart failure. RESULTS After home oxygen therapy, SAS improved from 2.5 +/- 0.9 to 3.3 +/- 1.0 METs(p < 0.0001), and SaO2 at rest improved from 92.8 +/- 2.5% to 96.3 +/- 1.6%(p < 0.0001). The frequency of admission was decreased from 1.3 +/- 1.2 to 0.8 +/- 1.2 times(p = 0.03). CONCLUSIONS Home oxygen therapy is effective for improving the symptoms and activity of daily life in patients with chronic heart failure. Home oxygen therapy may prevent the deterioration of heart failure.
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Affiliation(s)
- R Kojima
- Division of Internal Medicine, Municipal Kasai Hospital, Yokoo 1-13, Hojo-cho, Kasai, Hyogo 675-2393
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29
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Nakatani M. Treatment of chronic suppurative otitis media with Broncasma Berna. Ear Nose Throat J 2001; 80:529. [PMID: 11523469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023] Open
Abstract
Broncasma Berna, an inactivated bacterial vaccine, has been safely used throughout the world for 30 years for the prevention or treatment of various infectious processes. Until now, there has been no published report regarding its use as a treatment for chronic suppurative otitis media. In this small study, five such patients (median age: 57 years) underwent a series of seven 0.05-ml injections of Broncasma Berna. In all cases, their otorrhea diminished markedly and their tympanic membranes were almost completely dry. The cost of treatment was extremely low.
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Affiliation(s)
- M Nakatani
- Nakatani Clinic, 91, 2-chome, Suginobaba, Wakayama 640-8212, Japan.
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30
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Hamazaki N, Kounoike Y, Makinodan K, Nakatani M, Usuba K, Ueda K, Okada T, Egawa S, Takeshita S, Ohishi H, Narita N. [Usefulness of three-dimensional color Doppler sonography for the differential diagnosis of subpleural lesions]. Nihon Kokyuki Gakkai Zasshi 2001; 39:453-60. [PMID: 11579522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
The purpose of our investigation was to assess the usefulness of three-dimensional color Doppler sonography (velocity mode and power mode) for the differential diagnosis of subpleural lesions. Thirty lesions (11 pneumonias, 5 lung abscesses, 11 primary lung cancers, 3 metastatic lung cancers) were examined. Three-dimensional images were reconstructed by a maximum intensity projection method. Three-dimensional representations of intralesional blood flow became available for all lesions approximately 11 seconds after scanning. In every case, the entire vasculature of the tumor, the pneumonia, the abscess, or the inflamed region of the lung was appreciated more easily from three-dimensional images than from two-dimensional images. We classified the color flow pattern of subpleural lesions depicted by color flow imaging into seven groups. Color flow was depicted better by the three-dimensional color Doppler power mode than the velocity mode. Three-dimensional color flow patterns observed in power mode, patterns of the pneumonias and the lung cancers differed significantly. Our results suggest that the three-dimensional color Doppler power mode is useful for the differential diagnosis of subpleural lesions.
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Affiliation(s)
- N Hamazaki
- Department of Internal Medicine, Saiseikai Nara Hospital, 4-643 Hachijo, Nara-shi 630-8145, Japan
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31
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Bando K, Satoh K, Matsubara S, Nakatani M, Nagahiro S. Hyperperfusion phenomenon after percutaneous transluminal angioplasty for atherosclerotic stenosis of the intracranial vertebral artery. J Neurosurg 2001; 94:826-30. [PMID: 11354418 DOI: 10.3171/jns.2001.94.5.0826] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
✓ The authors report on a patient who underwent percutaneous transluminal angioplasty (PTA) for stenosis of the intracranial vertebral artery (VA). This 67-year-old man's dizziness while walking was caused by infarction of the left cerebellar peduncle. On angiograms, his left VA manifested 90% stenosis at the intracranial portion and his right VA ended at the posterior inferior cerebellar artery. Because single-photon emission computerized tomography (SPECT) showed low perfusion and poor perfusion reserve in the posterior circulation, the authors performed PTA of the left VA, which was only 35% dilated due to stenosis. Although the patient's postoperative course was uneventful, postoperative hemodynamic studies (SPECT and transcranial Doppler [TCD] ultrasonography) revealed the hyperperfusion phenomenon. A 100% increase of regional cerebral blood flow in the posterior circulation was demonstrated on SPECT studies and TCD ultrasonography revealed a doubling of blood flow velocity in the VA compared with preoperative values. Careful control of the patient's blood pressure resulted in resolution of the hyperperfusion phenomenon within 1 week post-PTA. Although hyperperfusion syndrome following carotid endarterectomy is not rare, it is seldom seen after reconstruction of the posterior circulation, and the possibility of its occurrence must be kept in mind when the posterior circulation is reconstructed.
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Affiliation(s)
- K Bando
- Department of Neurosurgery, School of Medicine, University of Tokushima, Kuramoto, Japan.
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32
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Adachi A, Komiyama T, Tanaka T, Nakatani M, Muguruma R, Okano T. Studies on defatted seed removal efficiency for organochlorine compounds. J Agric Food Chem 2000; 48:6158-6162. [PMID: 11312788 DOI: 10.1021/jf000951w] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Defatted seeds were evaluated for effective adsorption of organochlorine compounds such as chloroform, dichloromethane, and trichloroethylene. The amounts of these compounds adsorbed were plotted against the equilibrium concentration of substances in solution on a logarithmic scale. A linear relationship was obtained, indicating that the adsorption reactions were of the Freundlich type. The removal of these organochlorine compounds by defatted seed was attributed to the uptake by intracellular particles called spherosomes.
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Affiliation(s)
- A Adachi
- Kobe Pharmaceutical University, Higashinada-ku, Kobe, 658-8558, Japan
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33
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Abstract
A gene encoding DNA ligase (lig(Tk)) from a hyperthermophilic archaeon, Thermococcus kodakaraensis KOD1, has been cloned and sequenced, and its protein product has been characterized. lig(Tk) consists of 1,686 bp, corresponding to a polypeptide of 562 amino acids with a predicted molecular mass of 64,079 Da. Sequence comparison with previously reported DNA ligases and the presence of conserved motifs suggested that Lig(Tk) was an ATP-dependent DNA ligase. Phylogenetic analysis indicated that Lig(Tk) was closely related to the ATP-dependent DNA ligase from Methanobacterium thermoautotrophicum DeltaH, a moderate thermophilic archaeon, along with putative DNA ligases from Euryarchaeota and Crenarchaeota. We expressed lig(Tk) in Escherichia coli and purified the recombinant protein. Recombinant Lig(Tk) was monomeric, as is the case for other DNA ligases. The protein displayed DNA ligase activity in the presence of ATP and Mg(2+). The optimum pH of Lig(Tk) was 8.0, the optimum concentration of Mg(2+), which was indispensable for the enzyme activity, was 14 to 18 mM, and the optimum concentration of K(+) was 10 to 30 mM. Lig(Tk) did not display single-stranded DNA ligase activity. At enzyme concentrations of 200 nM, we observed significant DNA ligase activity even at 100 degrees C. Unexpectedly, Lig(Tk) displayed a relatively small, but significant, DNA ligase activity when NAD(+) was added as the cofactor. Treatment of NAD(+) with hexokinase did not affect this activity, excluding the possibility of contaminant ATP in the NAD(+) solution. This unique cofactor specificity was also supported by the observation of adenylation of Lig(Tk) with NAD(+). This is the first biochemical study of a DNA ligase from a hyperthermophilic archaeon.
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Affiliation(s)
- M Nakatani
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Yoshida-Honmachi, Sakyo-ku, Kyoto 606-8501, Japan
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34
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Iwagawa T, Kaneko M, Okamura H, Nakatani M, van Soest RW, Shiro M. A new quinolizidine alkaloid from the Papua New Guinean sponge Xestospongia exigua. J Nat Prod 2000; 63:1310-1311. [PMID: 11000048 DOI: 10.1021/np000111b] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A new bis-quinolizidine alkaloid, xestosin A (1), possessing cis- and trans-quinolizidine nuclei, has been isolated from the Papua New Guinean sponge Xestospongia exigua. The structure was determined by spectrometric and single-crystal X-ray analyses.
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Affiliation(s)
- T Iwagawa
- Faculty of Science, Kagoshima University, Korimoto Kagoshima 890-0065, Japan.
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35
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Terahara N, Konczak-Islam I, Nakatani M, Yamakawa O, Goda Y, Honda T. Anthocyanins in callus induced from purple storage root of Ipomoea batatas L. Phytochemistry 2000; 54:919-922. [PMID: 11014289 DOI: 10.1016/s0031-9422(00)00099-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Two anthocyanins were isolated from the highly pigmented callus derived from the storage root of purple sweet potato (Ipomoea batatas L.) cultivar 'Ayamurasaki'. One was identified as cyanidin 3-O-sophoroside-5-O-glucoside, and the other as cyanidin 3-O-(2-O-(6-O-(E)-p-coumaroyl-beta-D-glucopyranosyl)-beta-D-glucop yranoside)-5-O-beta-D-glucopyranoside, by chemical and spectroscopic analysis.
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Affiliation(s)
- N Terahara
- Department of Food Science and Technology, College of Horticulture, Minami-Kyushu University, Takanabe, Miyazaki, Japan.
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36
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Suzuki H, Murakami M, Kondo T, Shibata M, Ezumi H, Okabayashi H, Yorozuya M, Makishima N, Hamazaki Y, Nakatani M, Namiki A, Katagiri T. [Changes of serum hepatocyte growth factor in coronary artery disease]. J Cardiol 2000; 35:319-24. [PMID: 10834175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Hepatocyte growth factor (HGF) is an endothelial cell specific growth factor involved in the repair of endothelial cells and collateral formation, however, the role for coronary artery disease is still unknown. We measured serum HGF level in various coronary artery diseases to examine the clinical significance. Serum HGF level was measured using the enzyme-linked immunosorbent assay method in patients with stable effort angina pectoris (n = 26), old myocardial infarction (n = 18), unstable angina pectoris (UAP; n = 10) and acute myocardial infarction (AMI; n = 21). As a control group, we selected 11 patients with neurocirculatory asthenia. Blood samples from peripheral veins were collected at cardiac catheterization before heparin administration. In the AMI group, blood samples were also collected at 48, 72 hr, 1, 2, 3 and 4 weeks from the peripheral veins and 48 and 72 hr after reperfusion from the coronary sinus. Serum HGF level was significantly higher in the UAP (0.41 +/- 0.12 ng/ml, p < 0.001) and AMI groups (0.38 +/- 0.26 ng/ml, p < 0.05) compared to the control group (0.19 +/- 0.09 ng/ml). Serum HGF level peaked 48 hr after reperfusion in both the peripheral veins (0.42 +/- 0.16 ng/ml) and coronary sinus (0.58 +/- 0.23 ng/ml) in the AMI group, with a significantly higher level in the coronary sinus than the peripheral veins (p < 0.05). No significant correlation between peak HGF level in the peripheral veins and peak creatine kinase (CK), CK-MB, ejection fraction and cardiac index was observed. Serum HGF was elevated in acute coronary syndrome, indicating advanced endothelial cell damage. HGF is produced, at least partially, in the heart in patients with AMI. Serum HGF level may be useful to detect endothelial cell damage rather than myocardial cell damage.
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Affiliation(s)
- H Suzuki
- Third Department of Internal Medicine, Showa University School of Medicine, Tokyo
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37
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Konczak-Islam I, Yoshinaga M, Nakatani M, Terahara N, Yamakawa O. Establishment and characteristics of an anthocyanin-producing cell line from sweet potato storage root. Plant Cell Rep 2000; 19:472-477. [PMID: 30754885 DOI: 10.1007/s002990050758] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Anthocyanin pigments accumulated in a cell line derived from storage-root explants of sweet potato (Ipomoea batatas L.) cv 'Ayamurasaki'. Somatic pro-embryos were induced on the explants cultured on Murashige and Skoog medium supplemented with 1 mg/l 2,4-D. The pro-embryo structures produced callus when transferred to MS medium with 0.5 mg/l 2,4-D. A cell line was isolated from this callus which accumulated anthocyanin pigment. The color value of the pigment extracted after 27 days of culture in MS medium with 2 mg/l 2,4-D was 8.2, which was very close to that of a pigment extracted from roots, which was 8.9. Most of the pigments from the cell extract were hydrophilic and appeared on the ODS-column HPLC with a lower retention time than the main anthocyanins of the root tissues. The majority of the pigments were identical with the root anthocyanins. Cell line-specific anthocyanins were detected.
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Affiliation(s)
- I Konczak-Islam
- Laboratory of Upland Crop Genetic Resources, Department of Upland Farming, Kyushu National Agricultural Experiment Station, 6644 Yokoichi, Miyakonojo, Miyazaki 885-0091, Japan e-mail: , , , , , , JP
| | - M Yoshinaga
- Laboratory of Upland Crop Genetic Resources, Department of Upland Farming, Kyushu National Agricultural Experiment Station, 6644 Yokoichi, Miyakonojo, Miyazaki 885-0091, Japan e-mail: , , , , , , JP
| | - M Nakatani
- Laboratory of Upland Crop Genetic Resources, Department of Upland Farming, Kyushu National Agricultural Experiment Station, 6644 Yokoichi, Miyakonojo, Miyazaki 885-0091, Japan e-mail: , , , , , , JP
| | - N Terahara
- Department of Food Science and Technology, College of Horticulture, Minami-Kyushu University, Takanabe, Miyazaki 884-0003, Japan, , , , , , JP
| | - O Yamakawa
- Laboratory of Upland Crop Genetic Resources, Department of Upland Farming, Kyushu National Agricultural Experiment Station, 6644 Yokoichi, Miyakonojo, Miyazaki 885-0091, Japan e-mail: , , , , , , JP
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38
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Iwagawa T, Nakamura K, Hirose T, Okamura H, Nakatani M. New xenicane diterpenes isolated from the acetone extract of the soft coral Xenia florida. J Nat Prod 2000; 63:468-472. [PMID: 10785415 DOI: 10.1021/np990470a] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Six new xenicane diterpenes have been isolated from the acetone extract of the soft coral Xenia florida. Two of them are diterpenes containing a bicyclic [4.3.1] ring system. Three of them seem to be precursors for diterpenes possessing the bicyclic [4.3.1] ring system. One is a common monocarbocyclic diterpene with a cyclononane skeleton.
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Affiliation(s)
- T Iwagawa
- Faculty of Science, Kagoshima University 1-21-35 Korimoto, Kagoshima 890-0065, Japan.
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39
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Kuroda K, Toida S, Kawamuro Y, Anzai N, Obara A, Nakatani M, Asano H. [Possibility of discharge and need for rehabilitation of psychiatric patients hospitalized for one year or more in Japan: a preliminary report. Committee on Rehabilitation Affairs, Subcommittee of Survey on Rehabilitation Need]. Seishin Shinkeigaku Zasshi 1999; 101:762-76. [PMID: 10586643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
A total of 19,342 psychiatric patients staying in a total of 143 hospitals in Japan for one year or more entered in this study in order to determine the possibility of discharge (POD) and the need for rehabilitation. Those who were assessed by the psychiatrist in charge to have POD provided community support was assured accounted for 32.5%. As for the levels of daily life functions measured with the GAF score, those assessed to have POD showed the maximum frequency between scores 51 and 60, while the others, who were not considered suitable for discharge, showed the maximum frequency between scores 21 and 30. On the other hand, the control group, consisting of subjects with psychiatric disabilities and living in the community while using day care or rehabilitation facilities, showed the maximum frequency of GAF scores between 51 and 60. Two-thirds of the study subjects were older than fifty, while in the control group those aged between 30 and 49 accounted for 49.0%, thus indicating that the residents of mental hospitals tend to be older. More than 60% of the study subjects had been staying in hospital for five years or more. Those without their own home accounted for about 60%.
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Affiliation(s)
- K Kuroda
- Osaka Prefecture University College of Social Welfare
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40
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Nakatani M. Treatment of recurrent hordeolum with Broncasma Berna. Eye (Lond) 1999; 13 ( Pt 5):692. [PMID: 10696340 DOI: 10.1038/eye.1999.197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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41
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Abstract
We clarified the role of K(ATP) channels in the mechanism of ischemic preconditioning by using K(ATP) channel opener, nicorandil, and K(ATP) channel inhibitor, glibenclamide. Forty anesthetized dogs were divided into five groups: (a) control (C), (b) ischemic preconditioning (PC), (c) intravenous infusion of nicorandil before PC (Ni), (d) glibenclamide pretreated with PC (Gl + PC), and (e) glibenclamide pretreated with Ni (Gl + Ni). All groups were followed by 60-min ischemia and 60-min reperfusion and analyzed by the biochemical procedures. At the end of 60-min reperfusion, percentage of segment shortening in C indicated paradoxic bulging. This value was significantly recovered in PC and Ni, but it was still negative in Gl + PC and Gl + Ni. Ca2+ -adenosine triphosphatase (ATPase) activity of sarcoplasmic reticulum (SR) was significantly decreased in C. In PC and Ni, this activity was significantly maintained; however, in Gl + PC and Gl + Ni, it was similar to that in C. State III respiration of mitochondria showed similarity to the changes in SR. These results indicated that the K(ATP) channel opener enhanced the effects of ischemic preconditioning, and its blockade abolished these phenomena. We conclude that the ATP-sensitive potassium channel may play one of key roles in the mechanisms of ischemic preconditioning in the dog model.
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Affiliation(s)
- E Geshi
- Third Department of Internal Medicine, Showa University School of Medicine, Tokyo, Japan
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42
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Nakatani M, Shirotani T, Kobayashi K, Satomi S, Ikeda Y, Kuniyoshi T, Tajiri E, Furuta Y, Motooka T. [Effects of low dose pimobendan in patients with cor-pulmonale]. J Cardiol 1999; 34:79-83. [PMID: 10466089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
The acute and chronic efficacy of low dose pimobendan (1.25 mg x 2/day) was evluated in patients with cor-pulmonale. Fifteen patients (12 men, 3 women, mean age 73 +/- 5 yr) with right ventricular dysfunction judged by Tei's Doppler index (> or = 0.4) and poor working capacity (exercise tolerance: 2.2-6.6 MET) were studied. Mean pulmonary artery pressure, cardiac output, total pulmonary resistance using Swan-Ganz catheter, and arterial oxygen and carbon dioxide pressure (PaO2, PaCO2) were measured before and 24 hr after pimobendan administration. Maximal oxygen intake (MET), saturation of arterial blood oxygen at rest and desaturation by treadmill stress test were measured before and 1 month after pimobendan administration. Pulmonary artery pressure decreased (17.6 +/- 4.7 to 10.2 +/- 2.3 mmHg, p < 0.001) and cardiac output increased (3.5 +/- 0.6 to 5.1 +/- 0.9 l/min, p < 0.001), resulting in decreased total pulmonary resistance (5.0 +/- 1.3 to 2.1 +/- 0.7 U, p < 0.001), and a mild decrease in PaO2 (74 +/- 8 to 70 +/- 10 mmHg, p < 0.05). Exercise tolerance improved significantly (4.8 +/- 1.7 to 6.8 +/- 2.2 MET, p < 0.001), without deterioration of PaO2 and desaturation. These results indicate that low dose pimobendan is useful for the treatment of patients with cor-pulmonale.
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Affiliation(s)
- M Nakatani
- Department of Internal Medicine, Kasai Municipal Hospital, Hyogo
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Iwagawa T, Nakashima R, Takayama K, Okamura H, Nakatani M, Doe M, Shibata K. New cembranes from the soft coral sarcophyton species. J Nat Prod 1999; 62:1046-1049. [PMID: 10425140 DOI: 10.1021/np9900066] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Three new cembranes, including one with a 13-membered carbocyclic ring, have been isolated from the soft coral Sarcophyton sp.
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Affiliation(s)
- T Iwagawa
- Faculty of Science, Kagoshima University, 1-21-35 Korimoto Kagoshima 890-0065, Japan, and Faculty of Science, Osaka City University, 3-3-138 Sugimoto Sugimoto-ku Osaka 558-0022, Japan
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44
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Iwasaki Y, Nakabayashi N, Nakatani M, Mihara T, Kurita K, Ishihara K. Competitive adsorption between phospholipid and plasma protein on a phospholipid polymer surface. J Biomater Sci Polym Ed 1999; 10:513-29. [PMID: 10357263 DOI: 10.1163/156856299x00450] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The competitive adsorption of proteins and phospholipids on omega-methacryloyloxyalkyl phosphorylcholine (MAPC) polymer was evaluated in this study. Albumin, fibrinogen, and dimyrstoyl phosphatidylcholine (DMPC) were used as model components. The amount of DMPC adsorbed on the MAPC polymers increased with an increase in the MAPC unit composition of the polymer. The methylene chain length of the MAPC unit was another factor influencing the DMPC adsorption when the MAPC unit composition of the MAPC polymer was low. The state of albumin and DMPC liposome adsorbed on the 2-methacryloyloxyethyl phosphorylcholine (MPC) polymer was determined by dynamic contact angle (DCA) measurement. The adsorption strength of albumin on the MPC polymer was weaker than that on the poly[n-butyl methacrylate (BMA)], that is, the albumin was detached from the MPC polymer during the rinsing process. On the poly(BMA) surface, no difference in the shape of the DCA loops before and after contact with the DMPC liposomal suspension was observed. Fibrinogen adsorption on the MAPC polymer was detected by gold-colloid labeled immunoassay. The amount of fibrinogen adsorbed on every MAPC polymer surface was reduced by addition of the DMPC liposome in the fibrinogen solution. The number of platelets adhered on the MAPC polymer was also decreased when the DMPC liposome was present in the fibrinogen solution during pretreatment. We concluded that phospholipids were preferentially adsorbed on the MAPC polymer surface compared with plasma protein and that the adsorbed phospholipids played an important role in showing an excellent blood compatibility on the MAPC polymer.
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Affiliation(s)
- Y Iwasaki
- Institute for Medical and Dental Engineering, Tokyo Medical and Dental University, Japan
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45
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Abstract
The aim of this study is to evaluate the role of non-selective endothelin blockade (TAK-044) in ischemic myocardial injury. Forty anesthetized rats were separated into four groups: 1) TAK-I group, after preinjection of TAK-044 (3 mg/kg), LAD was ligated for 60 min and reperfused for 60 min; 2) Saline (SAL)-I group, LAD ligation and reperfusion without TAK-044; 3) TAK-C group, sham operated TAK group; 4) SAL-C group, sham-operated SAL group. Myocardium from each group was separated and analyzed by biochemical and ultrastructural procedures. Reperfusion arrhythmia (VT) was observed in 88% of the SAL-I group, in contrast to only 36% of the TAK-I group. At the end of reperfusion, hemodynamics indicated no significant differences between these two groups. The Ca(++)-ATPase activity of sarcoplasmic reticulum (SR) was 3.9 mumoles Pi/mg protein/h (39% of SAL-C group) in the SAL-I group, while that in the TAK-I group was significantly higher at 6.1 (54%). The ratio of infarct/risk area was 58% in the SAL-I group and 36% in the TAK-I group. In the ultrastructural observations, irreversibly injured cells of the ischemic portion were reduced significantly from 35% (SAL-I group) to 14% (TAK-I group). Thus, our results indicated that endothelin blockade reduced ischemic cellular injury. The mechanism of this reduction was speculated to be a resistance to ischemic injury in the subcellular levels of the myocardium conferred by a reduction of vascular constriction and improvement of imbalance in the energy supply and demand.
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Affiliation(s)
- E Geshi
- Third Department of Internal Medicine, Showa University School of Medicine, Tokyo, Japan.
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46
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Geshi E, Ishioka H, Nomizo A, Nakatani M, Katagiri T. Biochemical and ultrastructural evaluations of the effect of ischemic preconditioning on ischemic myocardial injury--role of the adenosine triphosphate-sensitive potassium channel. Jpn Circ J 1998; 62:915-24. [PMID: 9890206 DOI: 10.1253/jcj.62.915] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The aim of this study was to clarify the role of the adenosine triphosphate (ATP)-sensitive potassium channel on the mechanism of ischemic preconditioning (IP). Thirty-five anesthetized dogs were divided into 5 groups: (1) Control (C), (2) IP, (3) intravenous infusion of nicorandil (Ni) prior to IP, (4) glibenclamide (G1) pretreated with IP (G1+IP), and (5) G1 pretreated with Ni (G1+Ni). All groups had 60 min ischemia followed by 60 min reperfusion, and were analyzed by biochemical and morphological procedures. At the end of the 60-min reperfusion, %segment shortening in C indicated paradoxical bulging. This value had significantly recovered in IP and Ni groups, but it was still negative in the G1+IP and G1+Ni groups. Ca++-ATPase activity of the sarcoplasmic reticulum (SR) was significantly decreased in C. In the IP and Ni groups, this activity was significantly maintained; however, in the G1+IP and G1+Ni groups it was similar to that in C. State 3 respiration of mitochondria showed similar changes in the SR. In the ultrastructural observations, severely damaged cells were not observed in the IP and Ni groups. These results indicated that an ATP-sensitive potassium channel opener enhanced the effects of IP and its blockade abolished these phenomena. It was conclude that the ATP-sensitive potassium channel may play a key role in the mechanism of IP.
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Affiliation(s)
- E Geshi
- Third Department of Internal Medicine, Showa University School of Medicine, Tokyo, Japan
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47
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Abstract
Two new bromopyrroles and a new diterpene possessing a 9-methyladenium moiety have been isolated from the Papua New Guinean sponge Agelas nakamurai Hoshino.
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Affiliation(s)
- T Iwagawa
- Faculty of Science, Kagoshima University, 1-21-35 Korimoto, Kagoshima 890-0065, Japan, and Institute for Systematics and Population Biology, University of Amsterdam, P.O. Box 94766, 1009 GT, Amsterdam, The Netherlands
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Yuan X, Takahashi N, Terashita T, Nakatani M, Mizuno K. Which vertebrae should be assessed in diagnosing osteoporosis by plain radiography? Comparative study of radiographic findings and bone mineral density measured by dual energy X-ray absorptiometry. J Orthop Sci 1998; 3:252-6. [PMID: 9732559 DOI: 10.1007/s007760050050] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
In 1990, the Ministry of Health and Welfare of Japan advocated a criterion for the diagnosis radiographic bone atrophy in lumbar vertebrae. We carried out a comparative study of this criterion (i.e. , radiographic bone atrophy grading) and bone mineral density measured by posteroanterior and lateral dual energy X-ray absorptiometry. We investigated the second to fourth lumbar vertebrae of 47 postmenopausal women (mean age, 67.2 years; range, 57-82 years), to determine which vertebra would most accurately indicate osteoporosis. A significant difference in bone mineral density (P < 0.01) was found between each grade of radiographic bone atrophy in all of the second, third, and fourth vertebrae examined. The highest correlation (r = 0.714) was found between the radiographic grades and the bone mineral density on lateral dual energy X-ray absorptiometry of the third lumbar vertebrae. Our visual determinations were dependable, radiographic and a examination of the third lumbar vertebra rather than that of other lumbar vertebrae was more helpful for the detection of radiographic bone atrophy. Plain radiographic film can provide a rough estimation of bone atrophy.
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Affiliation(s)
- X Yuan
- Department of Orthopaedic Surgery, Nakatani Hospital, 105 Shinzaike, Hiraoka-cho, Kakogawa 675-01, Japan
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49
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Badar/'o R, Nakatani M, Chun P. New test for serelogical diagnosis of Visceral Leishmaniasis. Parasitol Int 1998. [DOI: 10.1016/s1383-5769(98)80043-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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50
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Kimura T, Nakatani M, Kawabe T, Yamaguchi A. Roles of conserved arginine residues in the metal-tetracycline/H+ antiporter of Escherichia coli. Biochemistry 1998; 37:5475-80. [PMID: 9548929 DOI: 10.1021/bi973188g] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Seven arginine residues are conserved in all the tetracycline/H+ antiporters of Gram-negative bacteria. Four (Arg67, -70, -71, and -127) of them are located in the putative cytoplasmic loop regions and three (Arg31, -101, and -238) in the putative periplasmic loop regions [Eckert, B., and Beck, C. F. (1989) J. Biol. Chem. 264, 11663-11670]. These arginine residues were replaced by alanine, lysine, or cysteine one by one through site-directed mutagenesis. None of the mutants showed significant alteration of the protein expression level. The mutants resulting in the replacement of Arg31, Arg67, Arg71, and Arg238 with either Ala, Cys, or Lys retained tetracycline resistance levels comparable to that of the wild type. Among them, only the Arg238 --> Ala mutant showed very low transport activity in everted membrane vesicles, probably due to the instability of the mutant protein. The replacement of Arg70 and Arg127 with Ala or Cys resulted in a drastic decrease in the drug resistance and almost complete loss of the transport activity, while the Lys replacement mutants retained significant resistance and transport activity, indicating that the positively charged side chains at these positions conferred the transport function. On the other hand, neither the Ala, Cys, nor Lys replacement mutant of Arg101 exhibited any drug resistance or transport activity. As for the reactivity of the Cys replacement mutants, only two (Arg71 --> Cys and Arg101 --> Cys) were not reactive with NEM, the other five mutants being highly or moderately reactive. The reactivity of the cysteine-scanning mutants around Arg101 with NEM revealed that Arg101 is located in transmembrane helix IV. It is not likely that Arg101 confers the protein folding through a salt bridge with a transmembrane acidic residue because no double mutants involving Arg101 --> Ala and the replacement of one of three transmembrane acidic residues (Asp15, Asp84, and Asp285) showed the recovery of any tetracycline resistance or transport activity. The effect of tetracycline on the [14C]NEM binding to the combined mutants S65C/R101A and L97C/R101A suggests that Arg101 may cause a substrate-induced conformational change of the putative exit gate of TetA(B).
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Affiliation(s)
- T Kimura
- Department of Cell Membrane Biology, Institute of Scientific and Industrial Research, Osaka University, Japan
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