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Yoshiike T, Benedetti F, Moriguchi Y, Vai B, Aggio V, Asano K, Ito M, Ikeda H, Ohmura H, Honma M, Yamada N, Kim Y, Nakajima S, Kuriyama K. Exploring the role of empathy in prolonged grief reactions to bereavement. Sci Rep 2023; 13:7596. [PMID: 37165097 PMCID: PMC10172345 DOI: 10.1038/s41598-023-34755-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 05/06/2023] [Indexed: 05/12/2023] Open
Abstract
Grief reactions to the bereavement of a close individual could involve empathy for pain, which is fundamental to social interaction. To explore whether grief symptoms interact with social relatedness to a person to whom one directs empathy to modulate the expression of empathy, we administered an empathy task to 28 bereaved adults during functional magnetic resonance imaging, in which participants were subliminally primed with facial stimuli (e.g., faces of their deceased or living relative, or a stranger), each immediately followed by a visual pain stimulus. Individuals' grief severity promoted empathy for the pain stimulus primed with the deceased's face, while it diminished the neural response to the pain stimulus primed with the face of either their living relative or a stranger in the medial frontal cortex (e.g., the right dorsal anterior cingulate cortex). Moreover, preliminary analyses showed that while the behavioral empathic response was promoted by the component of "longing" in the deceased priming condition, the neural empathic response was diminished by the component of "avoidance" in the stranger priming condition. Our results suggest an association between grief reactions to bereavement and empathy, in which grief symptoms interact with interpersonal factors to promote or diminish empathic responses to others' pain.
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Affiliation(s)
- Takuya Yoshiike
- Department of Sleep-Wake Disorders, National Institute of Mental Health, National Center of Neurology and Psychiatry, 4-1-1 Ogawahigashi, Kodaira, Tokyo, 187-8553, Japan.
| | - Francesco Benedetti
- Psychiatry and Clinical Psychobiology, Division of Neuroscience, Scientific Institute Ospedale San Raffaele, Milan, Italy
- University Vita-Salute San Raffaele, Milan, Italy
| | - Yoshiya Moriguchi
- Department of Behavioral Medicine, National Institute of Mental Health, National Center of Neurology and Psychiatry, Kodaira, Japan
| | - Benedetta Vai
- Psychiatry and Clinical Psychobiology, Division of Neuroscience, Scientific Institute Ospedale San Raffaele, Milan, Italy
- University Vita-Salute San Raffaele, Milan, Italy
| | - Veronica Aggio
- Psychiatry and Clinical Psychobiology, Division of Neuroscience, Scientific Institute Ospedale San Raffaele, Milan, Italy
- University Vita-Salute San Raffaele, Milan, Italy
| | - Keiko Asano
- Department of Human Sciences, Faculty of Human Sciences, Musashino University, Tokyo, Japan
| | - Masaya Ito
- National Center for Cognitive Behavior Therapy and Research, National Center of Neurology and Psychiatry, Kodaira, Japan
| | - Hiroki Ikeda
- National Institute of Occupational Safety and Health, Japan Organization of Occupational Health and Safety, Kawasaki, Japan
| | - Hidefumi Ohmura
- Department of Information Sciences, Faculty of Science and Technology, Tokyo University of Science, Noda, Japan
| | - Motoyasu Honma
- Department of Physiology, Showa University School of Medicine, Tokyo, Japan
| | - Naoto Yamada
- Department of Psychiatry, Shiga University of Medical Science, Otsu, Japan
| | - Yoshiharu Kim
- Department of Behavioral Medicine, National Institute of Mental Health, National Center of Neurology and Psychiatry, Kodaira, Japan
| | - Satomi Nakajima
- Department of Behavioral Medicine, National Institute of Mental Health, National Center of Neurology and Psychiatry, Kodaira, Japan
- Department of Human Sciences, Faculty of Human Sciences, Musashino University, Tokyo, Japan
| | - Kenichi Kuriyama
- Department of Sleep-Wake Disorders, National Institute of Mental Health, National Center of Neurology and Psychiatry, 4-1-1 Ogawahigashi, Kodaira, Tokyo, 187-8553, Japan
- Department of Psychiatry, Shiga University of Medical Science, Otsu, Japan
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Ebisuda Y, Mukai K, Takahashi Y, Ohmura H. Effect of high ambient temperature on physiological responses during incremental exercise in Thoroughbred horses. Comparative Exercise Physiology 2023. [DOI: 10.3920/cep220018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2023]
Abstract
Several reports have suggested that the risk of exertional heat illness (EHI) in Thoroughbred racehorses increases in high ambient temperatures. Heat dissipation in horses during exercise becomes less efficient when the body temperature and ambient temperature are close. Therefore, we hypothesised that exercise at 40 °C may increase body temperature, oxygen consumption, and cardiac output during incremental exercise tests compared to 20 and 30 °C. Six trained Thoroughbred horses were studied in a randomised, crossover design at three ambient temperatures with a 6-day washout period. Using a 3% inclined treadmill, horses performed incremental exercise tests at 1.7, 3.5, 6, 8, and 10 m/s for 90 s at ambient temperatures of 20, 30, and 40 °C. The effects of ambient temperature at 10 m/s on physiological variables were analysed using mixed models (P<0.05). Pulmonary arterial temperature and rectal temperature at 40 °C were higher than those at 20 °C (P<0.001) and 30 °C (P<0.001). Similarly, oxygen consumption (vs 20 °C, P=0.009; vs 30 °C, P=0.006) and cardiac output (vs 20 °C, P=0.001; vs 30 °C, P=0.001) at 40 °C were higher than those at 20 and 30 °C. Arterial O2 partial pressure, O2 saturation, and pH at 40 °C were lower than those at 20 and 30 °C. Arterial CO2 partial pressure at 40 °C was higher than that at 20 and 30 °C. No differences were observed in arterial-mixed venous O2 concentration difference (P=0.391) and plasma lactate concentration (P=0.134) at different ambient temperatures. These results indicate that exercise at 40 °C causes excessive high body temperature, decreased running economy, and increased cardiac output compared to exercise at 20 and 30 °C. We strongly suggest that trainers and veterinarians should anticipate the occurrence of increased thermal stresses when ambient temperature is extremely high even in dry conditions and prepare to mitigate the risk of EHI from the perspective of equine welfare.
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Affiliation(s)
- Y. Ebisuda
- Sports Science Division, Equine Research Institute, Japan Racing Association, Shiba1400-4, Shimotsuke, Tochigi 329-0412, Japan
| | - K. Mukai
- Sports Science Division, Equine Research Institute, Japan Racing Association, Shiba1400-4, Shimotsuke, Tochigi 329-0412, Japan
| | - Y. Takahashi
- Sports Science Division, Equine Research Institute, Japan Racing Association, Shiba1400-4, Shimotsuke, Tochigi 329-0412, Japan
| | - H. Ohmura
- Sports Science Division, Equine Research Institute, Japan Racing Association, Shiba1400-4, Shimotsuke, Tochigi 329-0412, Japan
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Kitaoka Y, Mukai K, Tonai S, Ohmura H, Takahashi T. Effect of post-exercise muscle cooling on PGC-1α and VEGF mRNA expression in Thoroughbreds. Comparative Exercise Physiology 2022. [DOI: 10.3920/cep210006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Besides preventing exertional heat illness, muscle cooling can be a potential strategy to enhance exercise-training induced adaptations. This study aimed to examine the effects of post-exercise cooling on the mRNA expression of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) and vascular endothelial growth factor (VEGF) in Thoroughbred skeletal muscle. Five Thoroughbred horses performed treadmill running until their pulmonary artery temperature reached 42 °C, followed by walking on the treadmill with no additional cooling (CONT) or muscle cooling with a shower using the tap water (26 °C, 0.4 l/s; COOL), for 30 min. Muscle biopsies were obtained before (PRE) and 3 h after exercise (3 Hr-REC) from the gluteus medius muscle. PGC-1α mRNA expression was elevated 3 h after exercise in both the CONT (PRE vs 3 Hr-REC: 1.0±0.1 vs 5.0±0.8, P<0.01) and COOL (PRE vs 3 Hr-REC: 1.1±0.3 vs 6.6±0.9, P<0.01) conditions; however, there was no difference between the two conditions at 3 h after exercise (P=0.17). VEGF mRNA expression was elevated 3 h after exercise in COOL (PRE vs 3 Hr-REC: 1.0±0.2 vs 2.2±0.2, P<0.05) but not in CONT (PRE vs 3 Hr-REC: 1.0±0.1 vs 1.8±0.3, P=0.08). VEGF mRNA expression at 3 h after exercise was significantly negatively correlated with rectal temperature at the end of the 30-min cooling period (r = -0.65, P<0.05). Our results suggest that the decline in body temperature after exercise may lead to greater expression of the key angiogenic gene in Thoroughbred horses.
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Affiliation(s)
- Y. Kitaoka
- Department of Human Sciences, Kanagawa University, 3-27-1 Rokkakubashi, Kanagawa-ku, Yokohama, Kanagawa, 221-8686, Japan
| | - K. Mukai
- Equine Research Institute, Japan Racing Association, 1400-4, Shiba, Shimotsuke, Tochigi, 329-0412, Japan
| | - S. Tonai
- Department of Human Sciences, Kanagawa University, 3-27-1 Rokkakubashi, Kanagawa-ku, Yokohama, Kanagawa, 221-8686, Japan
| | - H. Ohmura
- Equine Research Institute, Japan Racing Association, 1400-4, Shiba, Shimotsuke, Tochigi, 329-0412, Japan
| | - T. Takahashi
- Equine Research Institute, Japan Racing Association, 1400-4, Shiba, Shimotsuke, Tochigi, 329-0412, Japan
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Takahashi Y, Mukai K, Ohmura H, Takahashi T. Changes in muscle activity with exercise-induced fatigue in Thoroughbred horses. Comparative Exercise Physiology 2021. [DOI: 10.3920/cep200044] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Understanding the effects of fatigue can provide guidance for training regimens and injury prevention. We have previously reported that the integrated-electromyogram (iEMG) values of the M. gluteus medius and brachiocephalicus decreased with exercise-induced fatigue, whereas those of the M. longissimus dorsi and infraspinatus were not affected. We hypothesised that exercise-induced fatigue would decrease the activities of the muscles associated with propulsive force but not associated with joint stabilisation. Surface EMG recordings of the forelimb muscles (M. triceps brachii, common digital extensor, ulnaris lateralis), and hindlimb muscles (M. semitendinosus, extensor digitorum longus, extensor digitorum lateralis and flexor digitorum lateralis) were conducted on eight Thoroughbreds. Horses galloped on a treadmill (grade, 3%) at a constant speed (12.6-14.8 m/s) until they could not maintain their position with minimal human encouragement (~5 min). The stride frequency, iEMG for a stride and median frequency during muscle discharge were calculated every 30 s. These parameters were compared between the start and end of the test phase for the leading and trailing limbs. The stride frequency (P<0.01) and iEMG values of the M. semitendinosus in both the leading (P<0.01) and trailing limbs (P<0.05) and those of the M. extensor digitorum longus in the trailing limbs (P<0.05) significantly decreased at the end of the test. No median frequency changes were observed in the assessed muscles. Although muscular fatigue itself was not detected, observed fatigue caused by high-intensity exercise resulted in inability to maintain speed, which was associated with decreased iEMG values in the hip extensor muscles that generate propulsive force. In contrast, almost all muscles that stabilise joints were unaffected by fatigue. One exception was the decreased muscle activity observed in the M. extensor digitorum longus of the trailing limb, which may suggest unstable ground contact. Muscle activity changes with fatigue might be associated with muscle functions.
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Affiliation(s)
- Y. Takahashi
- Sports Science Division, Equine Research Institute, Japan Racing Association, 1400-4, Shiba, Shimotsuke, Tochigi, Japan
| | - K. Mukai
- Sports Science Division, Equine Research Institute, Japan Racing Association, 1400-4, Shiba, Shimotsuke, Tochigi, Japan
| | - H. Ohmura
- Sports Science Division, Equine Research Institute, Japan Racing Association, 1400-4, Shiba, Shimotsuke, Tochigi, Japan
| | - T. Takahashi
- Sports Science Division, Equine Research Institute, Japan Racing Association, 1400-4, Shiba, Shimotsuke, Tochigi, Japan
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Kitaoka Y, Mukai K, Takahashi K, Ohmura H, Hatta H. Effect of lactate administration on exercise-induced PGC-1α mRNA expression in Thoroughbreds. Comparative Exercise Physiology 2020. [DOI: 10.3920/cep200009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The aim of this study was to examine the effects of lactate administration on the mRNA response of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) to acute exercise in Thoroughbred skeletal muscle. Five Thoroughbred horses performed treadmill running at 90% of maximal oxygen consumption for 2 min on two separate occasions, either after the administration of two litres of a sodium lactate solution (LAC; 500 mmol/l sodium lactate in 0.9% NaCl) or a saline solution as a control (CON; 0.9% NaCl). Lactate administration significantly elevated the peak plasma lactate concentration during exercise (16.0±2.8 mmol/l in LAC vs 10.8±2.2 mmol/l in CON). The increase in PGC-1α mRNA expression after 4 h of recovery from exercise was similar between treatments. However, there was positive correlation between exercise-induced PGC-1α mRNA response at 4 h after exercise and peak plasma lactate concentration during exercise. These results suggest that the exercise intensity-dependent adaptation of PGC-1α may be attributed, at least in part, to an increased lactate concentration.
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Affiliation(s)
- Y. Kitaoka
- Department of Human Sciences, Kanagawa University, 3-27-1 Rokkakubashi, Kanagawa-ku, Yokohama, Kanagawa, 221-8686, Japan
| | - K. Mukai
- Equine Research Institute, Japan Racing Association, 1400-4, Shiba, Shimotsuke-shi, Tochigi, 329-0412, Japan
| | - K. Takahashi
- Department of Sports Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo, 153-8902, Japan
| | - H. Ohmura
- Equine Research Institute, Japan Racing Association, 1400-4, Shiba, Shimotsuke-shi, Tochigi, 329-0412, Japan
| | - H. Hatta
- Department of Sports Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo, 153-8902, Japan
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Makiyama A, Arimizu K, Hirano G, Makiyama C, Matsushita Y, Shirakawa T, Ohmura H, Komoda M, Uchino K, Inadomi K, Kusaba H, Shinohara Y, Kuwayama M, Kajitani T, Esaki T, Baba E. P-171 The impact on survival of CPT-11 as third-line or later treatment in advanced gastric cancer. Ann Oncol 2016. [DOI: 10.1093/annonc/mdw199.165] [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: 11/14/2022] Open
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Takahashi T, Ohmura H, Mukai K, Matsui A, Aida H. Fatigue in the Superficial and Deep Digital Flexor Muscles During Exercise in Thoroughbred Horses. Equine Vet J 2014. [DOI: 10.1111/evj.12267_90] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Affiliation(s)
- T Takahashi
- Equine Research Institute; Japan Racing Association; Utsunomiya Japan
| | - H Ohmura
- Equine Research Institute; Japan Racing Association; Utsunomiya Japan
| | - K Mukai
- Equine Research Institute; Japan Racing Association; Utsunomiya Japan
| | - A Matsui
- Equine Research Institute; Japan Racing Association; Utsunomiya Japan
| | - H Aida
- Equine Research Institute; Japan Racing Association; Utsunomiya Japan
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Ohmura H, Mukai K, Takahashi T, Aida H, Jones J. Cardiopulmonary Function in Thoroughbred Horses Running Uphill and Downhill on an Inclined Treadmill. Equine Vet J 2014. [DOI: 10.1111/evj.12267_75] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- H Ohmura
- Equine Research Institute; Japan Racing Association; Utsunomiya Tochigi Japan
| | - K Mukai
- Equine Research Institute; Japan Racing Association; Utsunomiya Tochigi Japan
| | - T Takahashi
- Equine Research Institute; Japan Racing Association; Utsunomiya Tochigi Japan
| | - H Aida
- Equine Research Institute; Japan Racing Association; Utsunomiya Tochigi Japan
| | - J Jones
- University of California; Davis CA United States
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Mukai K, Hiraga A, Takahashi T, Ohmura H, Jones JH. Effects of Different Exercise Intensities During Detraining on Aerobic Capacity in Thoroughbred Horses. Equine Vet J 2014. [DOI: 10.1111/evj.12267_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- K Mukai
- Equine Research Institute; Japan Racing Association; Utsunomiya Tochigi Japan
| | - A Hiraga
- Equine Research Institute; Japan Racing Association; Utsunomiya Tochigi Japan
| | - T Takahashi
- Equine Research Institute; Japan Racing Association; Utsunomiya Tochigi Japan
| | - H Ohmura
- Equine Research Institute; Japan Racing Association; Utsunomiya Tochigi Japan
| | - JH Jones
- University of California; Davis CA United States
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Akira A, Ohmura H, Uzumcu M, Araki T, Lin YC. Gossypol inhibits aromatase activity in cultured porcine granulosa cells. Theriogenology 2012; 41:1489-97. [PMID: 16727503 DOI: 10.1016/0093-691x(94)90200-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/1993] [Accepted: 03/08/1994] [Indexed: 11/25/2022]
Abstract
The present study investigated whether gossypol inhibited aromatase activity in cultured porcine granulosa cells. Aromatase activity was assayed by measuring (3)H-H(2)O released from [1beta-(3)H]-androstenedione. First, immature porcine granulosa cells were cultured with various doses of follicle stimulating hormone (FSH, 1 to 1000 ng/ml) for 1 to 5 d to determine optimal culture conditions for aromatase activity assay. Second, porcine granulosa cells were cultured with or without FSH in the presence or absence of gossypol. Gossypol, at 4 muM, significantly inhibited FSH-induced aromatase activity while showing no effect on basal aromatase activity. Gossypol did not inhibit cell proliferation during cell culture. These results suggest that gossypol inhibits aromatase activity by interfering with FSH induction of aromatase in cultured porcine granulosa cells.
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Affiliation(s)
- A Akira
- Laboratory of Reproductive Endocrinology Department of Veterinary Physiology and Pharmacology College of Veterinary Medicine The Ohio State University 1900 Coffey Road Columbus, OH 43210-1092 USA
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Ohmura H, Mukai K, Takahashi T, Matsui A, Hiraga A, Jones JH. Comparison of net anaerobic energy utilisation estimated by plasma lactate accumulation rate and accumulated oxygen deficit in Thoroughbred horses. Equine Vet J 2011:62-9. [PMID: 21058984 DOI: 10.1111/j.2042-3306.2010.00261.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
REASONS FOR PERFORMING STUDY Accumulated O(2) deficit (AOD) and plasma lactate accumulation rate (PLAR) are alternative methods for estimating net anaerobic energy utilisation (NAEU) in exercising horses. How they compare or their accuracy is unknown. OBJECTIVES We hypothesised net anaerobic energy utilisation calculated by PLAR (NAUE(PLAR)) is equivalent to NAUE estimated by AOD (NAUE(AOD)). METHODS Six Thoroughbred horses ran at identical supramaximal speeds (118% aerobic capacity) until exhaustion for 2 runs while breathing normoxic (NO, 21% O(2)) or hyperoxic (HO, 26% O(2)) gas. Jugular blood was sampled at 15 s intervals to measure plasma lactate concentration. Horses also ran at incremental submaximal speeds from 1.7-11.0 m/s to determine the linear relationship between speed and O(2) consumption to estimate O(2) demand for AOD calculations. RESULTS Maximum O(2) consumption of horses increased 11.6 ± 2.3% in HO and NAEU(PLAR) and NAUE(AOD) decreased 38.5 ± 8.0% and 46.2 ± 17.7%, respectively. The NAEU(PLAR) in NO was 114.5 ± 27.4 mlO(2) (STPD) equivalent/kg bwt contributing 23.5 ± 3.7% to total energy turnover and in HO was 70.9 ± 19.8 mlO(2) (STPD) equivalent/kg bwt contributing 14.6 ± 3.8% to total energy turnover. The NAUE(AOD) in NO was 88.6 ± 24.3 mlO(2) (STPD) equivalent/kg bwt contributing 19.9 ± 2.1% to total energy turnover and in HO was 56.2 ± 19.1 mlO(2) (STPD) equivalent/kg bwt contributing 10.9 ± 4.3% to total energy turnover. Overall, NAEU(AOD) was systematically biased -23.5 ± 16.8 mlO(2) (STPD) equivalent/kg bwt below NAEU(PLAR). Total energy demand estimated by PLAR was 11.1 ± 5.4% greater than that estimated by AOD and was higher in every horse. CONCLUSIONS The NAUE(PLAR) estimates average 40.0 ± 29.6% higher than NAUE(AOD) and are highly correlated (r(2) = 0.734), indicating both indices are sensitive to similar changes in NAEU. Accuracy of the estimates remains to be determined. Multiple considerations suggest NAUE(AOD) may underestimate total energy cost during high-speed galloping, thus biasing low the AOD estimate of NAEU.
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Affiliation(s)
- H Ohmura
- Equine Research Institute, Japan Racing Association, Tochigi, Utsunomiya, Tokami-cho, Japan.
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Mukai K, Hiraga A, Takahashi T, Ohmura H, Jones JH. Effects of three warm-up regimens of equal distance on VO2 kinetics during supramaximal exercise in Thoroughbred horses. Equine Vet J 2011:33-9. [PMID: 21058980 DOI: 10.1111/j.2042-3306.2010.00227.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [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: 12/01/2022]
Abstract
REASONS FOR PERFORMING STUDY Several studies have indicated that even low-intensity warm-up increases O(2) transport kinetics and that high-intensity warm-up may not be needed in horses. However, conventional warm-up exercise for Thoroughbred races is more intense than those utilised in previous studies of equine warm-up responses. OBJECTIVES To test the hypothesis that warm-up exercise at different intensities alters the kinetics and total contribution of aerobic power to total metabolic power in subsequent supramaximal (sprint) exercise in Thoroughbred horses. METHODS Nine well-trained Thoroughbreds ran until fatigue at 115% of maximal oxygen consumption (VO2max) 10 min after warming-up under each of 3 protocols of equal running distance: 400 s at 30% VO2max (LoWU), 200 s at 60% VO2max (MoWU) and 120 s at 100% VO2max (HiWU). Variables measured during exercise were rates of O(2) and CO(2) consumption/production (VO2,VO2), respiratory exchange ratio (RER), heart rate, blood lactate concentration and accumulation rate and blood gas variables. RESULTS VO2 was significantly higher in HiWU than in LoWU at the onset of the sprint exercise and HR was significantly higher in HiWU than in LoWU throughout the sprint. Accumulation of blood lactate, RER, P(a)CO(2) and PvCO2 in the first 60 s were significantly lower in HiWU than in LoWU and MoWU. There were no significant differences in stroke volume, run time or arterial-mixed venous O(2) concentration. CONCLUSIONS These results suggest HiWU accelerates kinetics and reduces reliance on net anaerobic power compared with LoWU at the onset of the subsequent sprint.
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Affiliation(s)
- K Mukai
- Equine Research Institute, Japan Racing Association, Tochigi, Japan.
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Hada T, Ohmura H, Mukai K, Eto D, Takahashi T, Hiraga A. Utilisation of the time constant calculated from heart rate recovery after exercise for evaluation of autonomic activity in horses. Equine Vet J 2010:141-5. [PMID: 17402409 DOI: 10.1111/j.2042-3306.2006.tb05530.x] [Citation(s) in RCA: 12] [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: 11/27/2022]
Abstract
REASONS FOR PERFORMING STUDY Heart rate (HR) recovery immediately after exercise is controlled by autonomic functions and the time constant (T) calculated from HR recovery is thought to be an index of parasympathetic activity in man. OBJECTIVES To investigate whether it is possible to evaluate autonomic function using the time constant in horses. METHODS Five Thoroughbred horses were subjected to a standard exercise test. Following pre-medication with saline, atropine and/or propranolol, the horses ran for 2.5 min at a speed of 8 m/sec at a 10% incline and T was calculated from HR after the exercise. Secondly, 7 Thoroughbred horses were then trained for 11 weeks and T and maximal oxygen uptake (VO2max) measured at intervals of 1 or 2 weeks. In 6 horses, T with atropine pre-medication was also measured before and after the whole training period. Furthermore, the HR variability at rest was evaluated by power spectral analysis at intervals of 3 or 4 weeks. RESULTS Time constant was increased by atropine and/or propranolol pre-medication, decreased with the progress of training and inversely correlated with VO2max during training (r = 0.43, P<0.005). Parasympathetic blockade significantly decreased T only after and not before, the training; however, T was lower in post training than in pretraining, irrespective of parasympathetic blockade. On the other hand, parasympathetic activity at rest was attenuated and sympathetic activity became predominant following the training. CONCLUSION Heart rate recovery is affected by sympathetic withdrawal and parasympathetic reactivation in horses and suggests that physical training hastened HR recovery by improving the parasympathetic function after exercise with aerobic capacity. However, the effects of other factors need to be considered because the training effect appeared on T even under parasympathetic blockade. The parasympathetic activity at rest is in contrast to that after exercise, suggesting that T does not reflect parasympathetic activity at rest. POTENTIAL RELEVANCE If demonstrated how HR recovery is controlled after exercise, its analysis will be important in the evaluation of physical fitness in horses.
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Affiliation(s)
- T Hada
- Equine Science Division, Hidaka Training and Research Center, Japan Racing Association, 535-13 Nischicha, Urakawa-cho, Uraakawagun, Hokkaido, Japan
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Matsui A, Ohmura H, Asai Y, Takahashi T, Hiraga A, Okamura K, Tokimura H, Sugino T, Obitsu T, Taniguchi K. Effect of amino acid and glucose administration following exercise on the turnover of muscle protein in the hindlimb femoral region of Thoroughbreds. Equine Vet J 2010:611-6. [PMID: 17402492 DOI: 10.1111/j.2042-3306.2006.tb05613.x] [Citation(s) in RCA: 11] [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: 11/29/2022]
Abstract
REASONS FOR PERFORMING STUDY In man, muscle protein synthesis is accelerated by administering amino acids (AA) and glucose (Glu), because increased availability of amino acids and increased insulin secretion, is known to have a protein anabolic effect. However, in the horse, the effect on muscle hypertrophy of such nutrition management following exercise is unknown. OBJECTIVES To determine the effect of AA and Glu administration following exercise on muscle protein turnover in horses. We hypothesise that administration of AA and Glu after exercise effects muscle hypertrophy in horses, as already shown in man and other animals. METHODS Measurements of the rate of synthesis (Rs) and rate of degradation (Rd) of muscle protein in the hindlimb femoral region of thoroughbred horses were conducted using the isotope dilution method to assess the differences between the artery and iliac vein. Six adult Thoroughbreds received a continuous infusion of L-[ring-2H5]- phenylalanine during the study, the stable period for plasma isotope concentrations (60 min), resting periods (60 min), treadmill exercise (15 min) and recovery period (240 min). All horses were given 4 solutions (saline [Cont], 10% AA [10-AA], 10% Glu [10-Glu] and a mixture with 10% AA and 10% Glu [10-Mix]) over 120 min after exercise, and the Rs and Rd of muscle protein in the hindlimb measured. RESULTS The average Rs during the 75-120 min following administration of 10-Mix was significantly greater than for the other solutions (P<0.05). The second most effective solution was 10-AA, and there was no change in Rs after 10-Glu. CONCLUSIONS Administration of AA following exercise accelerated Rs in the hindlimb femoral region, and this effect was enhanced when combined with glucose, because of increasing insulin secretion or a decreased requirement for AA for energy. POTENTIAL RELEVANCE Further studies are required regarding the effect on muscle hypertrophy of supplementing amino acids and glucose in the feed of exercising horses.
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Affiliation(s)
- A Matsui
- Equine Science Division, Hidaka Training and Research Center, Japan Racing Association, Urakawa-gun, Hokkaido, Japan
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15
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Abstract
REASONS FOR PERFORMING STUDY Thoroughbred racehorses often experience interruptions to their training. Identifying the effects of these changes and how they alter athletic performance might provide an insight on to how to prevent these changes from occurring. HYPOTHESIS Training and detraining young Thoroughbreds alters their aerobic capacities with correlated changes in circulatory capacities; if horses remained spontaneously active in a pasture during their detraining period, their decreases in aerobic capacity during detraining would be reduced. METHODS We trained 6 Thoroughbred yearlings for 6 months using a conventional yearling race training programme. They were then detrained for 10 weeks with free range on pasture for 8 h/day and stall rest at night. Treadmill measurements of O2 transport variables were made before training (PRE), after training (TR) and after detraining (DT). A step-test protocol identified each horse's aerobic capacity (VO2max) and speed to attain it, and a steady-state run at VO2max was used to quantify 02 transport variables at each time period. RESULTS The mass-specific and whole-body VO2max, cardiac output (Q) and stroke volume (Vs) increased from PRE to TR. All mass-specific values decreased significantly from TR to DT; however, because body mass increased by 8.3% from TR to DT, none of the variables changed significantly from TR to DT on a whole-body basis. CONCLUSIONS Changes in aerobic capacity are highly correlated with changes in Vs and circulatory capacity during training and detraining. Exercise activity of trained young horses free at pasture for 8 h/day is sufficient to maintain VO2max, (Q and Vs during 10 weeks of DT. POTENTIAL RELEVANCE Aerobic and cardiovascular fitness may be maintained in young Thoroughbred horses during at least 10 weeks of detraining by maintaining modest spontaneous exercise activity.
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Affiliation(s)
- K Mukai
- Equine Research Institute, Japan Racing Association, 321-4 Tokami-cho, Utsunomiya-city, Tochigi Prefecture, Japan
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16
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Abstract
REASON FOR PERFORMING STUDY Human athletes run faster and experience fewer injuries when running on surfaces with a stiffness 'tuned' to their bodies. We questioned if the same might be true for horses, and if so, would running on surfaces of different stiffness cause a measurable change in the amount of energy required to move at a given speed? HYPOTHESIS Different brands of commercial treadmills have pans of unequal stiffness, and this difference would result in different metabolic power requirements to locomote at a given speed. METHODS We tested for differences in stiffness between a Mustang 2200 and a Säto I commercial treadmill by incrementally loading each treadmill near the centre of the pan with fixed weights and measuring the displacement of the pan as weights were added or removed from the pan. We trained six 3-year-old Thoroughbreds to run on the 2 treadmills. After 4 months the horses ran with reproducible specific maximum rates of O2 consumption (VO2max/kg bwt, 2.62 +/- 0.23 (s.d.) mlO2 STPD/sec/kg) at 14.2 +/- 0.7 (s.d.) m/sec. They were alternately run on the 2 treadmills at identical grade (0.40 +/- 0.02%) and speeds (1.83 (walk), 4.0 (trot) and 8.0 (canter) m/sec, all +/- 0.03 m/sec) while wearing an open-flow mask for measurement of VO2. RESULTS The Mustang treadmill was over 6 times stiffer than the Säto. The VO2/kg bwt increased by approximately 4-fold over the range of speeds studied on both treadmills. Oxygen consumption was significantly lower at all speeds for the Mustang treadmill compared to the Säto. The fractional difference in energy cost decreased by a factor of 6 with increasing speed, although absolute difference in cost was relatively constant. CONCLUSIONS We suggest it costs less energy for horses to walk, trot or canter on a stiffer treadmill than on a more compliant treadmill, at least within the ranges of stiffness evaluated. POTENTIAL RELEVANCE It may be possible to define a substrate stiffness 'tuned' to a horse's body enabling maximal energetic economy when running. The differences between treadmills allows more accurate comparisons between physiological studies conducted on treadmills of different stiffness, and might help to identify an ideal track stiffness to reduce locomotor injuries in equine athletes.
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Affiliation(s)
- J H Jones
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, California 95616, USA
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17
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Abstract
REASON FOR PERFORMING STUDY There is no good method for measuring net anaerobic power in exercising horses to allow accurate estimates of total metabolic power. HYPOTHESIS The increase in VO2max when breathing hyperoxic (HO) gas should be accompanied by a stoichiometrically equal (in terms of ATP turnover, i.e. energy equivalents) decrease in plasma lactate accumulation rate (Mlactate). METHODS Six 3-year-old Thoroughbreds were trained on an equine treadmill wearing a semi-open flow mask for measurement of VO2. After 4 months the horses ran with reproducible specific VO2max (VO2max/kg bwt). The mask design allowed mixing of O2 or N2 with the inward bias flow of gas so that inspired O2 concentration of the horse could be controlled. While the horse breathed either HO (25.1% O2), normoxic (NO, 21% O2) or hypoxic (LO, 19.5% O2) gas, it ran at a speed sufficient to elicit VO2max in NO while jugular venous blood was drawn at 15 sec intervals over a period of 2 min to determine Mlactate. RESULTS VO2max/kg bwt was not significantly different between LO and NO conditions, and LO data could not be used in the comparison. The VO2max/kg bwt increased from 2.59 +/- 0.24 (s.d.) to 2.86 +/- 0.24 mlO2 (STPD)/sec/kg in NO and HO, respectively, while Mlactate decreased from 11.5 +/- 4.2 to 9.0 +/- 3.9 mmol/min as VO2 increased. CONCLUSIONS The ratio of delta Mlactate to delta VO2max/kg bwt suggests that Mlactate of approx 11.1 +/- 6.7 mmol/min is associated with net anaerobic power approximately equivalent to 1.0 mlO2 (STPD)/sec/kg of aerobic power (20.1 W/kg(-1)). The high variability in VO2max/kg bwt observed in data from some runs, particularly in LO, suggests that caution must be used when comparing data from the same horse during different runs. POTENTIAL RELEVANCE This study provides a tool for estimating net anaerobic power and, more accurately, evaluating total metabolic power of horses exercising at or above their aerobic capacities.
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Affiliation(s)
- H Ohmura
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
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18
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Miyazaki T, Iwama Y, Shimada K, Kume A, Sumiyoshi K, Ohmura H, Watanabe Y, Mokuno H, Daida H. W08-P-020 Association between hyperinsulinemia and severity of coronary artery disease in patients with normal glucose tolerance. ATHEROSCLEROSIS SUPP 2005. [DOI: 10.1016/s1567-5688(05)80136-9] [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]
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Affiliation(s)
- H Ohmura
- Equine Science Division, Hidaka Training and Research Center, Japan Racing Association, 535-13 Aza-Nishicha, Urakawa-cho, Urakawa-gun, Hokkaido 057-0171, Japan
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20
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Abstract
Yearling horses are typically trained for more than a year before they begin racing; therefore, we questioned how relevant analyses of the initial responses to training are compared to physiological responses that occur over a year of training, and whether young horses with no history of training would respond the same as older horses that had been trained previously. We hypothesised that changes in O2 transport over the last months of a year of training would be different than at the beginning. We trained 5 yearling Thoroughbreds and evaluated metabolism, O2 transport and echocardiograms. Measurements were made before breaking (T1), after 6 months of training (T2) and following an additional 4 months of training (T3). We compared 5 trained horses (TR) with 5 untrained (UT) sex-, size- and age-matched yearlings kept at pasture and in boxes. Satellite telemetry indicated UT moved less total daily distance than TR during winter and more during summer, but UT walked for 80% of their distance, TR only 25%. The UT increased body mass (Mb) after T1 by 13% and were significantly heavier and fatter than TR. Specific aerobic capacity (VO2max/Mb) increased by 16% in both groups at T2, but by T3 was not different from T1 in UT, but was higher in TR (19%>T1, 15%>UT). In TR, specific cardiac output (Q/Mb) increased by 13% at T2, and specific stroke volume (V(S)/Mb) were larger at T2 and T3 than T1 and UT at the same times both by physiological (15-16%) and echocardiographical (22-23%) estimates. Increased Vs was a primary correlate of the sustained increase in VO2max/Mb in TR. The large increases in V(S) and VO2max had occurred by T2 and changed only slightly by T3.
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Affiliation(s)
- H Ohmura
- Equine Science Division, Hidaka Training and Research Center, Japan Racing Association, Urakawa-gun, Hokkaido
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21
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Ohmura H, Hiraga A, Matsui A, Aida H, Inoue Y, Sakamoto K, Tomita M, Asai Y. Changes in running velocity at heart rate 200 beats/min (V200) in young thoroughbred horses undergoing conventional endurance training. Equine Vet J 2002; 34:634-5. [PMID: 12358007 DOI: 10.2746/042516402776180142] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- H Ohmura
- Equine Science Division, Hidaka Training and Research Center, Japan Racing Association, Urakawa-gun, Hokkaido
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22
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Ohmura H, Hiraga A, Aida H, Kuwahara M, Tsubone H. Effects of repeated atropine injection on heart rate variability in Thoroughbred horses. J Vet Med Sci 2001; 63:1359-60. [PMID: 11789620 DOI: 10.1292/jvms.63.1359] [Citation(s) in RCA: 19] [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: 11/22/2022] Open
Abstract
To investigate the effects of repeated atropine injection on heart rate (HR) variability in resting Thoroughbred horses, two microg/ kg of atropine as parasympathetic nervous blockade was injected intravenously every 6 min to a total of 8 microg/kg after intravenous administration of 0.2 mg/kg of propranolol as sympathetic nervous blockade. We recorded electrocardiograms and obtained the HR, then evaluated variation in HR from the power spectrum in terms of low frequency (LF, 0.01-0.07 Hz) power and high frequency (HF, 0.07-0.6 Hz) power. Administration of atropine decreased parasympathetic nervous activity in a dose-dependent manner, affecting first the LF power, then the HF power and finally HR. These responses may provide valuable information for evaluating autonomic nervous activity in Thoroughbred horses.
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Affiliation(s)
- H Ohmura
- Equine Science Division, Hidaka Yearling Training Farm of Japan Racing Association, Urakawa-gun, Hokkaido, Japan
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23
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Mikami K, Ohba S, Ohmura H, Kubodera N, Nakagawa K, Okano T. Asymmetric catalytic ene-cyclization approach to 2-fluoro-19-nor-1,25-dihydroxyvitamin D(3) A-ring analog with significant transactivation activity. Chirality 2001; 13:366-71. [PMID: 11400190 DOI: 10.1002/chir.1046] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [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: 11/10/2022]
Abstract
1alpha,25-Dihydroxyvitamin D(3) (1alpha,25(OH)2D3) has been shown to modulate not only proliferation and differentiation, but also apoptosis in malignant cells, indicating that it could be useful for the treatment of cancer and psoriasis. However, little information has been available on the binding conformation of the 1alpha,25(OH)2D3 molecule and its analogs with the vitamin D receptor (VDR). Therefore, we synthesized 2alpha-fluorinated A-ring analogs of 19-nor-1alpha,25(OH)2D3 in order to investigate the VDR-binding conformation of the A-rings on the basis of the (19)F NMR analysis. The 2alpha-fluoro-19-nor-1alpha,25-dihydroxyvitamin D3 A-ring analog thus synthesized via a asymmetric catalytic carbonyl-ene cyclization, shows significant activity in transactivation.
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Affiliation(s)
- K Mikami
- Department of Chemical Technology, Tokyo Institute of Technology, Tokyo 152-8552, Japan.
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24
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Kawatani T, Suou T, Tajima F, Ishiga K, Omura H, Endo A, Ohmura H, Ikuta Y, Idobe Y, Kawasaki H. Incidence of hepatitis virus infection and severe liver dysfunction in patients receiving chemotherapy for hematologic malignancies. Eur J Haematol 2001; 67:45-50. [PMID: 11553266 DOI: 10.1034/j.1600-0609.2001.067001045.x] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.7] [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: 12/16/2022]
Abstract
Hepatitis virus infection through virus reactivation has a high risk of mortality in patients with hematological malignancies receiving chemotherapy. We examined the incidence of both hepatitis B virus (HBV) and hepatitis C virus (HCV) infection and severe liver dysfunction (alanine aminotransferase >ten times the normal upper limit and total bilirubin >5 mg/dl) during chemotherapy in 268 patients with hematological malignancies. Eight patients (3.0%) were infected with HBV and 22 patients (8.2%) were infected with HCV. One patient (0.4%) was infected with both HBV and HCV. HBV- or HCV-infected patients showed severe liver dysfunction at a significantly higher incidence than non-infected patients (11/31 (35.5%) vs. 0/237 (0%), p<0.0001). Furthermore, the incidence of severe liver dysfunction in HBV-infected patients was significantly higher than in HCV-infected patients (6/8 (75.0%) vs. 4/22 (18.2%), p<0.01). Three of eight HBV-infected patients were initially negative for hepatitis B surface antigen (HBsAg) by latex agglutination and became positive for HBsAg during chemotherapy. Furthermore, all three patients developed severe liver dysfunction and two developed fatal fulminant hepatitis. From an examination of the original stock of serum samples before chemotherapy, two patients were found to be positive for HBV-DNA by polymerase chain reaction (PCR). Although post-transfusion HBV infection was suspected in the one remaining patient, the cause of HBV infection could not be clarified due to the impossibility of examination in blood donors. Since HBV-infected patients develop severe liver dysfunction at a higher incidence than either patients not infected with virus or HCV-infected patients before chemotherapy for hematological malignancies, it is recommended that HBV-DNA should be tested by PCR to detect HBV marker-negative carriers and liver function tests should be carefully monitored.
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Affiliation(s)
- T Kawatani
- Second Department of Internal Medicine, Faculty of Medicine, Tottori University, Yonago, Japan
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25
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Takahashi T, Hiraga A, Ohmura H, Kai M, Jones JH. Frequency of and risk factors for epistaxis associated with exercise-induced pulmonary hemorrhage in horses: 251,609 race starts (1992-1997). J Am Vet Med Assoc 2001; 218:1462-4. [PMID: 11345311 DOI: 10.2460/javma.2001.218.1462] [Citation(s) in RCA: 35] [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: 11/20/2022]
Abstract
OBJECTIVE To determine the frequency of epistaxis during or after racing among racehorses and identify factors associated with development of epistaxis. DESIGN Retrospective study. SAMPLE POPULATION 247,564 Thoroughbred and 4,045 Anglo-Arab race starts. PROCEDURE Race start information (breed, age, sex, racing distance, and race type) was obtained for Thoroughbred and Anglo-Arab horses racing in Japan Racing Association-sanctioned races between 1992 and 1997. All horses that raced were examined by a veterinarian within 30 minutes of the conclusion of the race; any horse that had blood at the nostrils was examined with an endoscope. If blood was observed in the trachea, epistaxis related to exercise-induced pulmonary hemorrhage (EIPH) was diagnosed. RESULTS Epistaxis related to EIPH was identified following 369 race starts (0.15%). Frequency of EIPH-related epistaxis was significantly associated with race type, age, distance, and sex. Epistaxis was more common following steeplechase races than following flat races, in older horses than in horses that were 2 years old, following races < or =1,600 m long than following races between 1,601 and 2,000 m long, and in females than in sexually intact males. For horses that had an episode of epistaxis, the recurrence rate was 4.64%. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that frequency of EIPH-related epistaxis in racehorses is associated with the horse's age and sex, the type of race, and the distance raced. The higher frequency in shorter races suggests that higher intensity exercise of shorter duration may increase the probability of EIPH.
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Affiliation(s)
- T Takahashi
- Equine Research Institute of the Japan Racing Association, Utsunomiya, Tochigi
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26
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Abstract
To determine oral dosage and to evaluate the pharmacokinetics in horses of orally administered flecainide, an antiarrhythmic drug, the correlations between its plasma concentration and PR, QRS and QT intervals in equine electrocardiograms (ECG) were investigated. Six healthy horses were administered a randomly ordered dose of 4 or 6 mg/kg of flecainide acetate. The ECG was monitored (heart rate (HR), PR, QRS, and QT intervals) and blood was taken at timed intervals to measure the plasma flecainide concentrations pre- and post-administration. The maximum plasma concentration reached 1014+/-285 (SD) ng/m/ in 45+/-13 min and 1301+/-400 ng/ m/l in 60+/-37 min for doses of 4 and 6 mg/kg flecainide, respectively. From the pharmacokinetic analysis, clearance rates were 14.6+/-6.4 and 11.7+/-5.2 ml/kg/min and terminal elimination half-lives were 228+/-53 and 304+/-87 min. The QRS and QT intervals increased significantly for both doses following administration, though HR and PR intervals did not change. Plasma flecainide concentrations were significantly correlated with QRS (r=0.935, P<0.001) and QT intervals (r=0.753, P<0.001). In conclusion, plasma concentrations of flecainide for treating equine atrial fibrillation were obtained by oral administration of 4 and 6 mg/kg, and the drug was rapidly eliminated from plasma in horses.
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Affiliation(s)
- H Ohmura
- Equine Science Division, Hidaka Yearling Training Farm of Japan Racing Association (JRA), Hokkaido
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27
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Sawano M, Watanabe Y, Ohmura H, Shimada K, Daida H, Mokuno H, Yamaguchi H. Potentially protective effects of the Ser447-Ter mutation of the lipoprotein lipase gene against the development of coronary artery disease in Japanese subjects via a beneficial lipid profile. Jpn Circ J 2001; 65:310-4. [PMID: 11316129 DOI: 10.1253/jcj.65.310] [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: 11/09/2022]
Abstract
Several DNA variants at the lipoprotein lipase (LPL) gene locus have been found to be associated with the plasma lipid levels and the prevalence of coronary artery disease (CAD). In particular, the Ser447-termination (Ter) mutation at the exon 9 of the LPL gene has the potential to elevate the plasma high-density lipoprotein (HDL) levels, but it remains unknown in the Japanese population. The present study investigated 93 CAD patients and 96 age- and sex-matched healthy controls. The Ser447-Ter mutation was determined by polymerase chain reaction restriction fragment length polymorphism method. The allelic frequency of the Ser447-Ter mutation was 0.103 in all subjects. The Ser447-Ter (GG and CG) group was associated with significantly higher levels of plasma HDL-cholesterol (p<0.001) and lower levels of plasma triglyceride than the CC group (p<0.02). The peak particle size of low-density lipoprotein (LDL) was significantly larger in the Ser447-Ter (GG and CG) group than in CC group (p<0.05). The frequency of the Ser447-Ter genotype in GG and CG was significantly lower in CAD than in the controls (11.9% vs 26%, odds ratio = 0.38; 95% confidence interval, 0.18-0.81; p<0.02). These results suggest that the Ser447-Ter mutation of the LPL gene is associated with high plasma HDL-cholesterol levels, low plasma triglyceride levels and a larger LDL particle size. This mutation may have a protective effect against the development of CAD via its favorable lipoprotein profile.
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Affiliation(s)
- M Sawano
- Department of Cardiology, Juntendo University, Tokyo, Japan.
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Ohmura H, Nukada T, Mizuno Y, Yamaya Y, Nakayama T, Amada A. Safe and efficacious dosage of flecainide acetate for treating equine atrial fibrillation. J Vet Med Sci 2000; 62:711-5. [PMID: 10945288 DOI: 10.1292/jvms.62.711] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [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
To determine a safe and efficacious dose of flecainide acetate for treating equine atrial fibrillation (Af), the safe dosage level was determined by injecting 1, 2, or 3 mg/kg i.v. of 1% flecainide acetate solution at a rate of 0.2 mg/kg/min to five clinically healthy horses. Clinical signs and the ECG were monitored (HR, PR, QRS, and QT intervals) and blood was taken to measure the plasma flecainide concentration pre- and post-administration. No abnormal signs were observed in the 1- or 2-mg/kg groups, while agitation was observed in three of five horses in the 3-mg/kg group. The QRS, and QT intervals for the 3-mg/kg group increased significantly. The peak plasma flecainide concentrations were 1.316 +/- 358 (SD) ng/ml, 1,904 +/- 314 ng/ml, and 2,251 +/- 387 ng/ml for the 1-, 2-, and 3-mg/kg groups, respectively. To evaluate the efficacy of flecainide, Af was induced by right atrial pacing in six clinically healthy horses, and 1% flecainide acetate solution was then administered until they converted to sinus rhythm. All horses with induced Af converted. For the conversion, a total dose of 1.40 +/- 0.63 mg/kg flecainide was required, the duration of administration was 7.00 +/- 3.15 min and plasma flecainide concentration at conversion was 1,303 +/- 566 ng/ml. In conclusion, flecainide acetate is a safe and effective antiarrhythmic agent for equine Af, and the clinically effective dosage is 1 to 2 mg/kg.
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Affiliation(s)
- H Ohmura
- Racehorse Clinic, Japan Racing Association Miho Training Center, Inashiki-gun, Ibaraki
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Sunayama S, Watanabe Y, Ohmura H, Sawano M, Shimada K, Mokuno H, Daida H, Yamaguchi H. Effects of troglitazone on atherogenic lipoprotein phenotype in coronary patients with insulin resistance. Atherosclerosis 1999; 146:187-93. [PMID: 10487503 DOI: 10.1016/s0021-9150(99)00138-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [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: 01/23/2023]
Abstract
Insulin resistance is associated with atherogenic lipoprotein phenotype, including small dense LDL particle, hypertriglycemia and low HDL cholesterol levels. Troglitazone, a novel insulin sensitizing agent, may improve the associated lipid profile in patients with insulin resistance. We examined the effects of troglitazone (400 mg daily for 12 weeks) in 12 non-diabetic coronary patients (60+/-10 years), all of whom had hyperinsulinemic response to an oral glucose load. Troglitazone markedly reduced the insulin response. After the treatment, plasma triglycerides decreased by 32% (P<0.05), HDL cholesterol increased by 11%, (P<0.05) and LDL peak particle diameter increased from 24.7+/-0.3 to 25.5+/-0.5 nm (P<0.01). These lipidic improvements were associated with a significant rise in postheparin lipoprotein lipase levels (175+/-52 to 217+/-69 ng/ml, P<0.01). In patients with insulin resistance syndrome, troglitazone improved the atherogenic lipoprotein phenotype as well as hyperinsulinemia. Our data suggest that troglitazone therapy could reduce the atherosclerotic risk due to insulin resistance even in non-diabetic patients.
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Affiliation(s)
- S Sunayama
- Department of Cardiology, Juntendo University, Tokyo, Japan.
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30
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Ohmura H, Watanabe Y, Hatsumi C, Sato H, Daida H, Mokuno H, Yamaguchi H. Possible role of high susceptibility of high-density lipoprotein to lipid peroxidative modification and oxidized high-density lipoprotein in genesis of coronary artery spasm. Atherosclerosis 1999; 142:179-84. [PMID: 9920519 DOI: 10.1016/s0021-9150(98)00235-4] [Citation(s) in RCA: 24] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Recent study demonstrated high susceptibility of plasma LDL to lipid peroxidative modification in patients with variant angina. Oxidized stress state, especially oxidized LDL, may induce coronary artery spasm by its impairing effect of endothelium-dependent arterial relaxation, but precise mechanisms remain unclear. Study subjects included 93 patients who underwent coronary angiographic examination: 12 patients with coronary artery spasm provoked by ergonovine without organic stenosis (group I), 11 patients who did not demonstrate coronary artery spasm or organic stenosis (group II) and 70 patients with organic coronary artery stenosis (group III). Levels of plasma HDL-cholesterol and apoA-I in group I were similar to those in III but were significantly lower than those in II, although the other plasma lipid parameters were not different among the three groups. The levels of TBARS in plasma and HDL were significantly higher in group I than in II or III (2.94+/-1.56 vs. 1.91+/-0.35 or 2.23+/-0.89 nmol MDA/ml and 1.23+/-1.00 vs. 0.54+/-0.37 or 0.70+/-0.63 nmol MDA/mg protein; P < 0.05), although the levels of TBARS in LDL were not significantly different. In the monitoring curve of diene production during copper-induced lipid peroxidation of HDL, its propagation slope was steeper and levels of maximum diene absorbance was higher in group I as compared with that in II or III, but not found in those of LDL. These results suggested that high susceptibility of HDL to lipid peroxidative modification in group I may contribute to the genesis of coronary artery spasm, and oxidized HDL rather than oxidized LDL is more likely to be related to coronary artery spasm.
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Affiliation(s)
- H Ohmura
- Department of Cardiology, Juntendo University School of Medicine, Tokyo, Japan
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Ohmura H, Wakahara M. Transformation of skin from larval to adult types in normally metamorphosing and metamorphosis-arrested salamander, Hynobius retardatus. Differentiation 1998; 63:238-46. [PMID: 9810702] [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: 02/09/2023]
Abstract
Transformation of skin from larval to adult types in a salamander, Hynobius retardatus, which had been reported to show neotenic reproduction in a specific environment, was examined morphologically in normally metamorphosing, precociously metamorphosing and metamorphosis-arrested larvae. Typical larval skin was composed of an epidermis constituted by three types of cells such as apical, Leydig, and basal cells. The Leydig cells were larval specific, and thus disappeared and were replaced by adult epidermal cells during the metamorphosis. Disappearance of the Leydig cells was accomplished by apoptosis as confirmed by the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end-labeling method and electron microscopy during the normal metamorphosis and precocious metamorphosis induced by exogenously applied triiodothyronine. Typical adult skin was composed of epidermis constituted by stratified squamous cells and of dermis mainly occupied with two types of dermal glands, mucous and serous glands. When the metamorphosis was arrested by different procedures (thyroidectomy, hypophysectomy, goitrogen treatment, and rearing at low temperature), the larval-specific Leydig cells fully remained in the epidermis, suggesting that the disappearance of these depended on the thyroid activity. Contrary to this, dermal glands behaved differently from the Leydig cells, though they developed and differentiated from epidermal basal cells and constituted the same skin. Those in the metamorphosis-arrested (thyroidectomized, hypophysectomized, or goitrogen-treated) larvae, except in the larvae reared at 4 degrees C, appeared a little later than in the controls. Thus, the aged, metamorphosis-arrested larvae had skin which consisted of larval type epidermis (Leydig cells) and adult type dermis (mucous and serous glands).
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Affiliation(s)
- H Ohmura
- Division of Biological Sciences, Graduate School of Science, Hokkaido University, Sapporo, Japan
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Sunayama S, Watanabe Y, Ohmura H, Sawano M, Ohmura T, Itoh S, Mokuno H, Daida H, Yamaguchi H. Effect of troglitazone in nondiabetic patients with coronary artery disease. J Am Coll Cardiol 1998. [DOI: 10.1016/s0735-1097(98)80388-4] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Sawano M, Watanabe Y, Ohmura H, Shimada K, Mokuno H, Daida H, Yamaguchi H. Lipoprotein lipase gene polymorphisms: associations with coronary artery disease and lipoprotein levels in Japanese population. J Am Coll Cardiol 1998. [DOI: 10.1016/s0735-1097(98)81287-4] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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34
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Hatsumi C, Watanabe Y, Sawano M, Ohmura H, Mokuno H, Daida H, Yamaguchi H. 1.P.245 The effect of the polymorphism at the 5′ -end of the apolipoprotein A-I gene on high density lipoprotein metabolism and coronary artery disease. Atherosclerosis 1997. [DOI: 10.1016/s0021-9150(97)88425-0] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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35
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Ohmura H, Watanabe Y, Mokuno H, Sawano M, Hatsumi C, Daida H, Yamaguchi H. 3.P.84 Increased susceptibility of small, dense low-density lipoprotein to oxidation in coronary artery disease. Atherosclerosis 1997. [DOI: 10.1016/s0021-9150(97)89159-9] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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36
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Miura N, Horikawa I, Nishimoto A, Ohmura H, Ito H, Hirohashi S, Shay JW, Oshimura M. Progressive telomere shortening and telomerase reactivation during hepatocellular carcinogenesis. Cancer Genet Cytogenet 1997; 93:56-62. [PMID: 9062581 DOI: 10.1016/s0165-4608(96)00329-9] [Citation(s) in RCA: 143] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Telomeres shorten progressively with age in normal somatic cells in culture and in vivo. The maintenance of telomere length is assumed to be an obligatory step in the progression and immortalization of most human tumor cells. To understand the role of telomere dynamics in the development of hepatocellular carcinoma (HCC), we examined the length of terminal restriction fragment (TRF), as an indicator for telomere length, in HCC and surrounding tissues with chronic active hepatitis (CAH) or liver cirrhosis (LC). The study was performed in 12 hepatitis C virus (HCV) antibody-positive, 12 hepatitis B virus (HBV) antigen-positive tissues, and 4 tissue samples from virus-negative patients with HCC. The peak TRFs in all 3 types of HCC were significantly shorter than those of the surrounding tissues (i.e., LC or CAH). TRFs examined in one patient with atypical adenomatous hyperplasia (AAH) also was shortened. Thus, progressive TRF shortening occurs from normal to CAH to LC to HCC(AAH). Telomerase, an enzyme that adds repeated telomere sequences onto the chromosome ends and stabilizes telomere length in immortal cells, also was examined in tissues and detected in high levels almost exclusively in HCCs. Interestingly, the intensity of telomerase activity in the AAH case was similar to that of HCC. In addition, the telomerase activity of biopsy samples with a fine 21-gauge needle also was examined in 10 HCCs, 2 adenomatous hyperplasias (AHs), 2 LCs, and 2 CAHs. We found strong telomerase activity in all the HCCs and surprisingly in the 2 cases that were pathologically diagnosed as AH. Thus, the findings strongly suggest that persistent cell proliferation or rapid cell turnover through damage of hepatic cells result in a process of multistep hepatocellular carcinogenesis. Thus, progressive shortening of telomeres and the activation of telomerase may be a useful marker for the early detection of malignant progression in liver disease.
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Affiliation(s)
- N Miura
- Department of Molecular and Cell Genetics, School of Life Sciences, Faculty of Medicine, Tottori University, Japan
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Zhao M, Zhao QX, Saitoh M, Ohmura H, Okamoto Y, Shrestha P, Mori M. Proliferating patterns of salivary gland adenocarcinomas with the use of PCNA labeling. Anticancer Res 1996; 16:2693-8. [PMID: 8917372] [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: 02/03/2023]
Abstract
Cellular proliferation activity in a series of salivary gland malignant tumors was evaluated using the index of proliferation cellular nuclear antigen (PCNA) immunoreactivity. A streptavidin-biotin immunoperoxidase method (ABC) using a monoclonal antibody PC10 demonstrated nuclear staining with varying intensity and distribution in all tumor specimens. Acinic cell carcinoma (n = 5) and polymorphous low-grade adenocarcinoma (n = 1) showed relatively low proliferation fractions. In adenoid cystic carcinoma (n = 13), PCNA-positive nuclei were mainly distributed in neoplastic myoepithelial cells which were the predominant cells in tumor growth. No statistically significant difference was found between cribriformtubular and solid subtypes. In adenocarcinoma (n = 6), a well differentiated papillary-cystic pattern expressed a significantly higher PCNA index than poorly differentiated solid pattern, showing the loss of the relationship between PCNA expression and differentiation. Tumor cell differentiation appears to be more important than proliferation in determining biological behavior and prognosis.
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Affiliation(s)
- M Zhao
- Stomatology Department, Henan Medical University, Zhengzhou, P.R. China
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38
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Li C, Okamoto Y, Ohmura H, Ogawa K, Shrestha P, Mori M. Expression of cytokeratins in Warthin's tumour (adenolymphoma) of parotid glands: specific detection of individual cytokeratin types by monoclonal antibodies. Eur J Cancer B Oral Oncol 1996; 32B:352-8. [PMID: 8944841 DOI: 10.1016/0964-1955(96)00023-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
This study evaluated the distribution of cytokeratins detected by monoclonal antibodies directed against individual keratin proteins in normal human salivary glands and epithelial tumour cells of Warthin's tumour arising in parotid glands to determine a more precise mapping of their cellular distribution. The normal salivary ducts showed the presence of cytokeratin 7, 8, 18 and 19 in the intercalated, striated and excretory ducts, the primary keratins of stratified and simple epithelia with a profile very similar to the non-cornified epithelium of the oral mucosa. The basally located cells of salivary gland ducts other than myoepithelial cells were reactive for keratins 7 and 19 suggesting a close similarity in profile of keratin in the basal cells of the oral epithelium. In Warthin's tumour, keratins 7, 8, 18 and 19 were consistently detected in the epithelial cells of the tumour, a profile with a tendency to mimic the same in normal ductal epithelium. The distribution, however, was diverse and a heterogeneity was observed in the basal and luminal cells of Warthin's tumour which differed even in different areas of the same tumour specimen.
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Affiliation(s)
- C Li
- Department of Oral and Maxillofacial Surgery, Asahi University School of Dentistry, Gifu, Japan
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Zhao M, Zhao Q, Saitoh M, Ohmura H, Okamoto Y, Shrestha P, Mori M. Heterogeneity of cytokeratin expression as revealed using monoclonal antibodies in salivary adenocarcinomas. Int J Oncol 1996; 9:65-72. [PMID: 21541482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023] Open
Abstract
Numerous neoplastic lesions of the salivary glands often share a number of similar histopathological features and different areas of the same tumor specimen, not infrequently, may show a diverse histomorphology. The present study evaluates expression of single keratin proteins recognized by monoclonal anti-K7, K8, K18, K19 and keratins recognized by monoclonal KL1 and K8.12 in tubular-duct-like or cribriform structures, solid nests, clear cells, microcystic, basaloid cells and squamous metaplastic histomorphology present in tissue specimens of adenoid cystic carcinoma (n=11), acinic cell carcinoma (n=5), polymorphous low grade adenocarcinoma (n=1) and adenocarcinoma, not otherwise specified (NOS, n=5) of salivary glands. Expression of vimentin in the epithelial tumor cells was further evaluated using an anti-vimentin monoclonal antibody. A great heterogeneity of keratin expression was observed in the luminal and abluminal cells forming the tubular-duct-like and cribriform structures. The abluminal cells in more than half of the instances of adenoid cystic carcinoma had immunoreactive vimentin. In addition, heterogeneity was more pronounced in tumor cells forming the solid nests, comedo-necrosis, microcysts, clear cells or squamous metaplasia. A heterogeneity of keratin profile in different histomorphologies of different tumor types and even in different areas of the same tumor specimen, in the present study, and the available evidence so far limits the use of cytokeratin immunostaining in the differential diagnosis of neoplastic salivary lesions and characterization of a particular histomorphology which, in many instances, are ubiquitous in different tumor subtypes.
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Affiliation(s)
- M Zhao
- ASAHI UNIV,SCH DENT,DEPT ORAL & MAXILLOFACIAL SURG,GIFU 50102,JAPAN. HENAN MED UNIV,DEPT STOMATOL,ZHENGZHOU 450052,PEOPLES R CHINA. HENAN MED UNIV,DEPT PATHOL,ZHENGZHOU 450052,PEOPLES R CHINA
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40
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Zhao M, Zhao Q, Saitoh M, Ohmura H, Okamoto Y, Shrestha P, Mori M. Heterogeneity of cytokeratin expression as revealed using monoclonal antibodies in salivary adenocarcinomas. Int J Oncol 1996. [DOI: 10.3892/ijo.9.1.65] [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: 11/06/2022] Open
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41
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Ohmura H. [Suppressive effect of Gossypol, Gossypolone and serum from Gossypol treated rats on steroidogenesis in cultured porcine granulosa cells]. Nihon Ika Daigaku Zasshi 1996; 63:181-9. [PMID: 8707919 DOI: 10.1272/jnms1923.63.181] [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: 02/01/2023]
Abstract
Gossypol (GP), a male antifertility agent, and Gossypolone (GN), a major metabolite of GP, have been shown to have a suppressive effect on steroidogenesis in bovine luteal cells. We examined the effect of GP, GN and serum obtained from rats given GP (GP-serum) on steroidogenesis in porcine granulosa cells (PGC). To obtain GP-serum, 50-60 day old Copenhagen rats received GP (12.5 mg/kg B.W./day, sc) for 14 days. PGC were incubated with GP, GN and GP-serum at different doses for 24 hours. GP and GN significantly suppressed Progesterone (P4) and Estradiol (E2) release in a dose-dependent manner, respectively. GP-serum also significantly suppressed P4 release in a dose-dependent manner. The magnitude of suppression of P4 obtained by GP-serum could not be explained by the amount of GP remaining in the serum. Therefore, the inhibition of P4 release by GP-serum could not be solely attributed to GP.
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Affiliation(s)
- H Ohmura
- Department of Obstetrics and Gynecology, Nippon Medical School, Tokyo, Japan
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42
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Ohmura H, Tahara H, Suzuki M, Ide T, Shimizu M, Yoshida MA, Tahara E, Shay JW, Barrett JC, Oshimura M. Restoration of the cellular senescence program and repression of telomerase by human chromosome 3. Jpn J Cancer Res 1995; 86:899-904. [PMID: 7493906 PMCID: PMC5920601 DOI: 10.1111/j.1349-7006.1995.tb02998.x] [Citation(s) in RCA: 99] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Telomeres, at the end of chromosomes, shorten with each cell division, resulting in cellular senescence. Tumor cells, unlike normal somatic cells, express a telomerase that maintains the telomere length. Deletion of a gene(s) on chromosome 3 is common in human renal cell carcinoma (RCC) and reintroduction of a normal chromosome 3 into an RCC immortal cell line restored the program of cellular senescence. The loss of indefinite growth potential was associated with the loss of telomerase activity and shortening of telomeres in the RCC cells with a normal chromosome 3. However, microcell hybrids that escaped from senescence and microcell hybrids with an introduced chromosome 7 or 11 maintained telomere lengths and telomerase activity similar to those of the parental RCC23. Thus, restoration of the cellular senescence program by chromosome 3 is associated with repression of telomerase function in RCC cells.
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Affiliation(s)
- H Ohmura
- Department of Molecular and Cell Genetics, School of Life Sciences, Faculty of Medicine, Tottori University
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Abstract
We investigated the expression of tenascin in a series of odontogenic tumours (n = 63) of epithelial and epithelial-ectomesenchymal origin by using immunohistochemical methods. A heterogeneity of expression of tenascin was observed in odontogenic tumours. The heterogeneity was most prominent in odontogenic tumours not forming calcified tissues. In these ameloblastomas and adenomatoid odontogenic tumours, tenascin was mainly localised at the epithelial tumour cell-mesenchymal tissue interface. In the calcifying epithelial odontogenic tumour, ameloblastic fibroma and odontoma, a widespread stromal immunoreactivity was observed which was, however, unreactive in the calcified masses. The stellate reticulum-like cells and granular cells of ameloblastoma also showed a positive immunoreactivity for tenascin. The results of the present study suggest that expression of tenascin in the stromal tissue of odontogenic tumours differs according to the potential of forming calcified masses by the tumour cells irrespective of tumour cell morphology.
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Affiliation(s)
- M Mori
- Department of Oral and Maxillofacial Surgery, Asahi University School of Dentistry, Gifu, Japan
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Etsuda H, Mizuno K, Kato R, Arakawa K, Miyamoto A, Nozaki Y, Nakao S, Ohmura H, Okamoto Y, Uehata A. [Adult case of aortopulmonary window with aortic regurgitation: a case report]. Kokyu To Junkan 1993; 41:1113-5. [PMID: 8256054] [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: 01/29/2023]
Abstract
A 45-year-old woman was admitted to our hospital because of the evaluation of heart murmur. Her height was 152 cm and body weight was 46 kg. The physical examination showed a grade 4 continuous murmur widely audible on the anterior chest wall. The chest X-ray film was normal. The electrocardiogram showed premature ventricular contractions and left ventricular (LV) hypertrophy. The two dimensional echocardiogram demonstrated the presence of moderate aortic regurgitation (AR), however, aortopulmonary window could not be detected. The aortic valve showed neither atherosclerotic nor rheumatic changes. At cardiac catheterization, pulmonary artery (PA) pressure was 20/11 mmHg and aortic pressure was 133/60 mmHg, and a step-up of O2 saturation between right ventricule and pulmonary artery (PA) was demonstrated. The aortography revealed an aortopulmonary window between the proximal ascending aorta and the main PA, and grade 2 AR. The pulmonary to systemic flow ratio averaged 1.5:1. The coronary artery and the LV wall motion was normal. Aortopulmonary window is a very rare anomaly and often requires operation in childhood because of its large left-to-right shunt in most cases. Neither an asymptomatic adult case with this anomaly nor a case with AR has not been reported so far.
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Affiliation(s)
- H Etsuda
- Department of Internal Medicine I, School of Medicine, National Defence Medical College
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Chang WY, Ohmura H, Kulp SK, Lin YC. Transforming growth factor-β1 regulates differentiation of porcine granulosa cells in vitro. Theriogenology 1993; 40:699-712. [PMID: 16727352 DOI: 10.1016/0093-691x(93)90206-k] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/1992] [Accepted: 06/09/1993] [Indexed: 11/20/2022]
Abstract
Transforming growth factor-beta (TGF-beta) is a potential regulator of ovarian function and follicular development. It is speculated that TGF-beta mediates the events in the follicle which culminate in ovulation of the oocyte. The complex processes which ultimately leads to this natural phenomenon must involve interactions between the 2 major follicular cell types, theca and granulosa cells, and the oocyte. Furthermore, a complex local regulatory system must exist to determine which follicles should undergo development and, eventually, which of those should ovulate or undergo atresia. To begin to understand this perplexing process, we must first understand the variables which control the function of each individual cell type. This study investigated the effect of TGF-beta(1) on FSH-induced porcine granulosa cell differentiation in vitro. Transforming growth factor-beta(1) was shown to inhibit progesterone production at high concentrations (0.1 and 10.0 ng/ml) after 12-, 24- and 48-hour treatment. However, TGF-beta(1) produced a biphasic effect on FSH-induced progesterone production during the 12-hour interval between the 36- and 48- hour treatment periods; TGF-beta(1) stimulated progesterone production at a low concentration (0.001 ng/ml) and inhibited production at high concentrations (0.1 and 10.0 ng/ml). The results obtained from the biphasic effect were not observed during any of the other incubation periods or intervals investigated. These results show that TGF-beta(1) has opposing effects on the differentiation of porcine granulosa cells as compared with those on rat granulosa cells. Moreover, TGF-beta(1) can produce opposing effects within the porcine granulosa cell itself which are specific to the concentration and treatment period used. The results of this study seem to suggest that TGF-beta(1) is species- and time-specific in its regulatory actions on FSH-induced porcine granulosa cell differentiation.
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Affiliation(s)
- W Y Chang
- Laboratory of Reproductive Endocrinology Department of Veterinary Physiology and Pharmacology College of Veterinary Medicine The Ohio State University 1900 Coffey Road Columbus, OH 43210-1092 USA
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Ohmura H, Oshimura M. [Telomere, cellular senescence and transformation]. Nihon Rinsho 1993; 51:1899-906. [PMID: 8366614] [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: 01/30/2023]
Abstract
Telomere is the structure which is located on both ends of individual chromosomes in eukaryotes. The DNA sequence of the telomere consists of Guanine-rich tandem repeat, i.e., (TTAGGG)n in man. Telomere protects the end of the chromosome from fusion or deletion and maintains the stability of the chromosome and is synthesized by telomerase, a ribonucleoprotein. Telomere reduction is observed with cell senescence and immortalization, both in vivo and in vitro. Thus, telomere is considered to be a "clock" which measures the life span of cells, and its length is altered by cellular senescence and immortalization.
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Affiliation(s)
- H Ohmura
- Department of Molecular and Cell Genetics, School of Life Science, Faculty of Medicine, Tottori University
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Kasemura T, Oshibe Y, Uozumi H, Kawai S, Yamada Y, Ohmura H, Yamamoto T. Surface modification of epoxy resin with fluorine-containing methacrylic ester copolymers. J Appl Polym Sci 1993. [DOI: 10.1002/app.1993.070471215] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Sasaki J, Gotoh J, Morihana K, Uematsu M, Takai H, Ohmura H, Abe H, Ikeshima K, Nishiyama K, Shiiki K. [A comparative double blind study of lenampicillin and talampicillin in the treatment of oral infections]. Jpn J Antibiot 1985; 38:2453-80. [PMID: 3908737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
A comparative double blind study of lenampicillin (LAPC, KBT-1585) and talampicillin (TAPC) was carried out in order to objectively evaluate efficacy, safety and utility of LAPC in treatment of 238 patients with oral infections. Cases accepted by the Central Committee for evaluation of efficacy and utility were 218, consisting of 101 of the LAPC group and 117 of the TAPC group; safety were 234, consisting of 110 of LAPC and 124 of TAPC. Clinical effectiveness as rated by attending doctor was 84.2% for the LAPC group and 82.9% for the TAPC group. The clinical utility rating was 82.2% in the LAPC group and 82.1% in the TAPC group, showing no significant difference between the 2 drugs. Adverse reactions were found in 6 cases (5.5%) in the LAPC group and 5 cases (4.0%) in the TAPC group, showing no significant difference between the 2 drugs. Cases accepted by the controllers for evaluation of efficacy and utility were 236, consisting of 111 cases of LAPC and 125 cases of TAPC. Those for safety were 236, consisting of 111 cases of LAPC and 125 of TAPC. The clinical effectiveness rating was 77.5% in the LAPC group and 79.2% in the TAPC group. Clinical utility rating was 75.7% in the LAPC group and 78.4% in the TAPC group. Rate of adverse reactions was 5.4% in the LAPC group and 4.0% in the TAPC group, showing no significant difference between the 2 drugs. Cases evaluated for efficacy according to numerical rating on the 3rd day were 200 cases, consisting of 93 of LAPC and 107 of TAPC. The effectiveness rate was 83.9% in the LAPC group and 95.3 in the TAPC group, showing a significant difference between the 2 drugs. On the other hand, taking into consideration evaluation scores of the 5th day, the effectiveness rate was 88.7% in the LAPC group and 96.1% in the TAPC group, showing no significant difference between the 2 drugs. The effectiveness rate in cases of isolated organisms was 84.9% in the LAPC group and 79.7% in the TAPC group, showing no significant difference between the 2 drugs. Adverse reactions were mostly of gastrointestinal origin. Symptoms were not serious and disappeared soon after administration was discontinued or immediately after administration was completed.(ABSTRACT TRUNCATED AT 400 WORDS)
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49
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Sasaki J, Gotoh J, Morihana K, Sekiguchi T, Takai H, Ohmura H, Abe H, Ikejima K, Nishiyama K, Shiiki K. [Clinical evaluation of lenampicillin in oral and maxillofacial infections]. Jpn J Antibiot 1985; 38:1468-508. [PMID: 4046173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Clinical efficacies of newly developed synthetic oral ampicillin prodrug lenampicillin (LAPC, KBT-1585) applied to 109 cases of oral infection were studied. There were 7 dropout cases. The results as determined on a point system are as follow: Remarkably effective, 26 cases; effective, 63 cases; and not effective, 13 cases, for an efficacy rate of 87.3%. When rated by the subjective judgement of the doctors in charge, these figures are as follow: remarkably effective, 21 cases, effective, 67 cases; slightly effective, 10 cases; and not effective, 4 cases. The rate of efficacy in this way being 86.3%. In either way, the results obtained were favorable. Among 102 cases in this study, pus was aspirated with sterile needle from obstructed abscesses in 65 cases, with the result that 161 strains of bacteria were isolated and identified. Most of infections were found mixed type by aerobic Gram-positive cocci and anaerobes. Especially, cases caused by alpha-Streptococcus were observed in 48 out of 55 mixed infective cases. LAPC's MIC distribution against the detected bacteria showed strong antibacterial effect as follows: against Gram-positive cocci, less than 0.39 micrograms/ml; against Gram-negative bacteria (excluding some insusceptible strains), less than 3.13 micrograms/ml. Thus, LAPC demonstrated a superiority when compared to CEX by 4 approximately 128-fold, and when compared to AMPC by about 2-fold. Adverse reactions among the 109 cases consisted of 6 cases of gastro-intestinal disorders including 3 cases of diarrhea. Recognized cases of abnormal laboratory findings were 3 cases out of 76 (3.9%), but none were serious.
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50
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Sasaki J, Yamada Y, Takai H, Ohmura H, Abe H, Shiki K, Narita Y, Michi K, Ohno K, Kawanishi I. [Clinical studies on TMS-19-Q.O tablets, the preparation of a new macrolide antibiotic, in the field of oral surgery]. Jpn J Antibiot 1985; 38:615-33. [PMID: 3897602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Multicenter clinical trial or TMS-19-Q.O tablet was performed to evaluate the usefulness in oral surgery. The results obtained were as follows: Clinical efficacy was assessed by clinical points. The patients entered into the trial were 77 cases with periodontitis, 23 with pericoronitis, 92 with osteitis of jaw and 18 with other infections, and the each effective rates were 80.5, 60.9, 83.7 and 72.2%, respectively. Overall effective rate was 79.0%. Isolation frequency of organisms were 33.8% in periodontitis, 34.8% in osteitis of jaw and 17.4% in pericoronitis. Bacteria isolated were aerobic organisms (63.1%) and anaerobic organisms (36.9%). TMS-19-Q.O tablet was well tolerated, and no adverse reaction was observed.
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