Jun Iwamoto's research while affiliated with Keiyu Hospital and other places

Publications (271)

Article
Full-text available
Sato Y, Iwamoto J, Honda Y, Amano N. Ther Clin Risk Manag. 2013;9:171–176. The Editor and Publisher of Therapeutics and Clinical Risk Management wish to retract the published article. Following publication of the Expression of Concern, this article has been retracted due to acknowledgement of allegations of scientific misconduct regarding data inte...
Article
Full-text available
Iwamoto J, Sato Y, Uzawa M, Takeda T, Matsumoto H. Ther Clin Risk Manag. 2010;6:593–600. The Editor and Publisher of Therapeutics and Clinical Risk Management wish to retract the published article. Following publication of the Expression of Concern, this article has been retracted due to acknowledgement of allegations of scientific misconduct regar...
Article
Full-text available
Sato Y, Iwamoto J, Honda Y, Amano N. Ther Clin Risk Manag. 2013;9:171–176 The Editor and Publisher of Therapeutics and Clinical Risk Management wish to publish an Expression of Concern for the published article. Concerns were raised to the Editor regarding the scientific integrity of the articles content. We have contacted the authors requesting th...
Article
The article entitled “Effects of Vitamin K2 on Osteoporosis, published in Curr Pharm Des 2004; 10(21): 2557-76, by Iwamoto J, Takeda T and Sato Y.” has been retracted by the Editorial office of the journal Current Pharmaceutical Design, as the text, data and some figures used/referred in this review article are from sources which have been retracte...
Article
IntroductionSince the definition of secondary amenorrhea is cessation of regular menses for more than 3 months, it is likely that athletes with irregular menstrual cycles, including oligomenorrhea, do not consider the condition as serious. However, the consequences of untreated oligomenorrhea have not been investigated in elite track and field athl...
Article
With intensive training, bone injuries are a major concern for athletes. To assess bone condition, we often measure bone turnover markers, bone mineral content and density; however, in junior athletes, it is not easy to distinguish changes caused by bone injuries from those caused by growth, because the metabolism is increased in both cases. Moreov...
Article
This article has been retracted. Please see the Retraction Notice for more detail: https://doi.org/10.1007/s00774-021-1209-0
Article
Background: Nutrient intake has an essential role in bone disorder prevention among long-distance runners. However, the influence of vitamin A intake on the risk of stress fractures remains unknown. This prospective study aimed to investigate the association between vitamin A intake, and stress fracture occurrence in male collegiate long-distance...
Article
Full-text available
Many elite female athletes struggle to maintain performance while transitioning from high school to university-level (senior) sports. This study explores factors of body composition that influenced performance in elite junior female track and field athletes transitioning to the senior division. Forty-two elite female track and field athletes, ranke...
Article
Full-text available
The Editors-in-Chief have retracted this article [1]. Serious concerns have been raised about the data presented [2], and after careful consideration and additional investigation the Editors-in-Chief no longer have confidence in this article.
Article
Full-text available
The Editors-in-Chief have retracted this article [1]. Serious concerns have been raised about the data presented [2], and after careful consideration and additional investigation the Editors-in-Chief no longer have confidence in this article. All authors were contacted and did not respond to correspondence about this retraction.
Article
Full-text available
The Editor-in-Chief has retracted this article [1] because an investigation by Keio University has concluded that there are inaccuracies in the data reported.
Article
The Editor has retracted this article [Iwamoto J, Sato Y, Uzawa M, Takeda T, Matsumoto H. Three-year Experience with Alendronate Treatment in Postmenopausal Osteoporotic Japanese Women with or without Renal Dysfunction: A Retrospective Study. Drugs Aging 2012; 29(2): 133-142.]. After publication, serious concerns were raised with respect to the rep...
Article
Full-text available
The Editor-in-Chief has retracted this article [1] because the three studies included in the meta-analysis [2,3 and 4] (cited as references 16, 17 and 18) have been retracted due to concerns regarding the data, which has rendered the results of this meta-analysis invalid. © 2018 Springer International Publishing AG, part of Springer Nature
Article
This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the Editors. Numerous concerns have been raised and verified regarding this paper, including authorship, lack of credible IRB review, and impla...
Article
The following articles have been retracted by the Editorial Board of Experimental Animals, because some parts of their contents were published elsewhere.
Article
The following articles have been retracted by the Editorial Board of Experimental Animals, because some parts of their contents were published elsewhere.
Article
The following articles have been retracted by the Editorial Board of Experimental Animals, because some parts of their contents were published elsewhere.
Article
The Editor-in-Chief has retracted this article because two of the three studies [1, 2] included in the meta-analysis (cited as references 11 and 12) have been retracted due to fabrication of the data, which has rendered the results of this meta-analysis invalid. © 2018 Springer International Publishing AG, part of Springer Nature
Article
The following articles have been retracted by the Editorial Board of Experimental Animals, because some parts of their contents were published elsewhere.
Article
The following articles have been retracted by the Editorial Board of Experimental Animals, because some parts of their contents were published elsewhere.
Article
The following articles have been retracted by the Editorial Board of Experimental Animals, because some parts of their contents were published elsewhere.
Article
In contemporary Japan, there is a polarizing trend in children who exercise more than 1,800 minutes a week and those who exercise less than 60 minutes a week. Quite a lot of girls in particular hate exercise,and therefore they don't get enough of it. Osteoporosis is a preventable disease from childhood. It is crucial for girls to exercise and to pr...
Article
Full-text available
Teriparatide (TPTD) is known to increase the cortical thickness and porosity. The purpose of the present study was to determine whether switching from TPTD to ibandronate (IBN) would be useful for improving cortical bone parameters as assessed using high-resolution quantitative computed tomography (HR-QCT) analyses in mature rabbits. Forty-two fema...
Article
Full-text available
Background: Whole-body vibration (WBV) exercise is widely used for training and rehabilitation. However, the optimal posture for training both the upper and lower extremities simultaneously remains to be established. Objectives: The objective of this study was to search for an effective posture to conduct vibration from the lower to the upper ex...
Chapter
The prevention of falls and subsequent osteoporotic fractures can reduce disability, improve quality of life, and reduce the costs of health care for older adults. Exercise plays an important role in preventing falls. A consensus has been reached that exercise programs that include balance and muscle-strengthening exercises, but not brisk walking,...
Article
Full-text available
A clinical practice-based observational study was performed to compare the outcome of alendronate (ALN) and teriparatide (TPTD) treatment among Japanese postmenopausal women with a history of fragility fractures. Sixty-one Japanese postmenopausal women with a history of fragility fractures were treated with ALN (35 mg weekly, n = 32) or TPTD (20 μg...
Article
Full-text available
We previously reported that alendronate and risedronate reduce the urinary levels of cross-linked N-terminal telopeptides of type I collagen (NTX) by 44.9% and 34.7%, respectively, at 3 months after the start of treatment, and increase the speed of sound (SOS) of the calcaneus by 0.6% and 0.65%, respectively, at 12 months after the start of treatme...
Article
Minodronate is a potent nitrogen-containing bisphosphonate that can be administered according to a monthly (every 4 weeks) dosing regimen. A 6-month, cluster-randomized, open-label, multicenter, crossover trial was conducted to test the preference of Japanese patients with osteoporosis for monthly bisphosphonate versus weekly bisphosphonate. One hu...
Article
The purpose of this practice-based observational study was to examine the effects of long-term treatment with risedronate in patients with an increased fracture risk. Seventy patients (4 men and 66 postmenopausal women; mean age, 68.0 years) with osteoporosis or osteopenia and clinical risk factors for fractures were treated with risedronate at eit...
Article
Full-text available
The purpose of the present study was to investigate sex-specific differences in injury types among basketball players. According to our database, during the 20-year period between October 1991 and June 2011, 1,219 basketball players (640 males and 579 females) consulted our sports medicine clinic; in total, 1,414 injuries in basketball players (729...
Article
A retrospective study was performed to evaluate the outcome of alendronate treatment for 7 years among Japanese men with osteoporosis or osteopenia and clinical risk factors for fractures. Thirty-five Japanese men with osteoporosis or osteopenia and clinical risk factors for fractures (mean age at baseline 58.2 years) who had been treated with alen...
Article
High-dose glucocorticoids reduce cortical bone gain in rats. The aim of the present study was to examine the effect of the intermittent administration of human parathyroid hormone (1-34) (hPTH[1-34]) on cortical bone in rats treated with high-dose prednisolone (PSL). Twenty-five female Sprague-Dawley rats (6 weeks old) were randomized into the foll...
Article
Gastrectomy (GX) induces osteopenia in rats. The present study examined the skeletal effects of vitamin K2 in GX rats. Thirty male Sprague-Dawley rats (12 wk old) were randomized by the stratified weight method into the following three groups of 10 animals each: sham operation (control) group; GX group; and GX+oral vitamin K2 (menatetrenone, 30 mg/...
Article
A prospective study was conducted to clarify the 1-year changes in lumbar spine and hip bone mineral density (BMD) and bone turnover markers in premenopausal amateur runners and to determine whether jumping and muscle-strengthening exercises have additive effects on the bone parameters in these runners. Thirty-six premenopausal amateur runners were...
Article
Serum undercarboxylated osteocalcin (ucOC) is an index of vitamin K nutritional status in treatment-naive postmenopausal osteoporotic women. The purpose of the present study was to reveal the association between vitamin K nutritional status and serum ucOC concentrations in postmenopausal osteoporotic women taking bisphosphonates. Eighty-six postmen...
Article
Full-text available
Vitamin K may play an important role in the prevention of fractures in postmenopausal women with osteoporosis. Menatetrenone is the brand name of a synthetic vitamin K2 that is chemically identical to menaquinone-4. The present review study aimed to clarify the effect of menatetrenone on the skeleton in postmenopausal women with osteoporosis, by re...
Article
The purpose of the present study was to determine whether teriparatide and monthly minodronic acid would have an additive effect on cancellous bone mass in ovariectomized rats. Seven-week-old female Sprague-Dawley rats were randomized into five groups of 10 animals each, including a sham-operation+vehicle group, an ovariectomy (OVX)+vehicle group,...
Article
Full-text available
A randomized controlled trial was conducted to clarify the beneficial effect of whole body vibration (WBV) exercise plus squat training on body balance, muscle power, and walking ability in the elderly with knee osteoarthritis and/or spondylosis. Of 35 ambulatory patients (14 men and 21 women) who were recruited at our outpatient clinic, 28 (80.0%,...
Article
Prescription of a bisphosphonate (BP) with monthly dosing has recently been approved in Japan. The value of this approach for improvement of medication adherence was investigated in patients undergoing drug therapy for osteoporosis. A questionnaire was distributed to patients receiving treatment for osteoporosis at 8 medical facilities (5 orthopedi...
Article
Full-text available
An open-label randomized controlled trial was conducted to clarify the effect of eldecalcitol (ED) on body balance and muscle power in postmenopausal osteoporotic women treated with bisphosphonates. A total of 106 postmenopausal women with osteoporosis (mean age 70.8 years) were randomly divided into two groups (n=53 in each group): a bisphosphonat...
Article
The purpose of the present study was to determine whether teriparatide and monthly minodronic acid would have an additive effect on cancellous bone mass in ovariectomized rats. Seven-week-old female Sprague–Dawley rats were randomized into five groups of 10 animals each, including a sham-operation + vehicle group, an ovariectomy (OVX) + vehicle gro...
Article
To examine the effects of treatment with risedronate for 1 year on speed of sound (SOS) of the calcaneus and bone turnover markers in postmenopausal women with osteoporosis. Thirty-eight postmenopausal women with osteoporosis who had been treated with risedronate for > 1 year were enrolled in the study. The SOS and bone turnover markers were monito...
Article
Objectives: Minodronate is a nitrogen-containing bisphosphonate that is commercially available for the treatment of osteoporosis in Japan. Preclinical studies demonstrated that minodronate is at least 10 times more potent than alendronate in inhibiting bone resorption in vivo. A high incidence of fractures, particularly of the hip, represents an i...
Article
The objective of the present study was to clarify the relationships between physical function, bone mass, biochemical markers, renal function, and a history of nonvertebral fracture in postmenopausal women with osteoporosis. In total, 143 postmenopausal women with osteoporosis (mean age: 71.2 years) and an osteoporosis treatment-naïve status were r...
Article
Hypovitaminosis D and K due to malnutrition or sunlight deprivation, compensatory hyperparathyroidism, increased bone resorption, low bone mineral density (BMD), and an increased risk of falls may contribute to an increased risk of hip fractures in patients with Alzheimer's disease. The purpose of the present study was to clarify the efficacy of in...
Article
Full-text available
Vitamin D supplementation is suggested to reduce the risk of falls in older institutionalized or ambulatory individuals by 20%. The present study was undertaken to address the reduced risk, by vitamin D supplementation, of falls and hip fractures in patients with vascular Parkinsonism (VP) and Parkinson's disease (PD). In the open-label-study, 94 e...
Article
Introduction: The effect of the anti-osteoporosis medicine, menatetrenone (vitamin K(2); menaquinone-4) on the skeleton remains a matter of controversy. The objective of the present review study was to evaluate the effect of menatetrenone on the skeleton of postmenopausal women, men and glucocorticoid-treated patients. Methods: PubMed was used to s...
Article
Full-text available
We report the 11-year follow-up of a man with osteogenesis imperfecta type I who was treated with bisphosphonates and alfacalcidol. A 36-year-old Japanese man with osteogenesis imperfecta type I who had frequently experienced painful fragility fractures consulted our clinic because of chronic back pain. The patient had multiple morphometric vertebr...
Article
Full-text available
The aim of the present study was to examine the influence of gastrectomy (GX) on cortical and cancellous bones in rats. Twenty male Sprague-Dawley rats were randomized into the two groups of 10 animals each: a sham operation (control) group and a GX group. Seven weeks after surgery, the bone mineral content and density (BMC and BMD, resp.) and the...
Article
Hypovitaminosis D and K due to malnutrition or sunlight deprivation, increased bone resorption due to immobilization, low bone mineral density (BMD) and an increased risk of falls may contribute to an increased risk of hip fractures in patients with Parkinson's disease. The purpose of the present study was to clarify the efficacy of interventions i...
Article
Full-text available
The objectives of this study were to reveal the proportion of Shorinji Kempo athletes who had suffered fractures related to sports activities, and to evaluate bone mass, bone turnover, nutritional status, and physical function in these athletes. A medical examination was carried out for 16 Shorinji Kempo collegiate athletes. Seven athletes (43.8%)...
Article
A randomized controlled trial was conducted to determine the effect of 6 months of whole body vibration (WBV) exercise on physical function in postmenopausal osteoporotic women treated with alendronate. Fifty-two ambulatory postmenopausal women with osteoporosis (mean age: 74.2 years, range: 51-91 years) were randomly divided into two groups: an ex...
Article
Intramuscularly administered elcatonin (ECT) reduces pain via the central nervous system. A prospective study was performed to determine whether ECT has a beneficial effect on back pain and function in postmenopausal women with osteoporosis during bisphosphonate therapy. Sixty-one postmenopausal osteoporotic women with back pain (mean age: 73.7 yea...
Article
We report on the case of a severely osteoporotic elderly Japanese woman with bisphosphonate-associated osteonecrosis of the jaw (ONJ), who was treated successfully with teriparatide. A 79-year-old woman with severe osteoporosis and bisphosphonate-associated ONJ was treated with teriparatide after debridement of the necrotic tissue in the jaw bone....
Article
Full-text available
The influence of alendronate (ALN) treatment on the quantitative ultrasound parameters of the calcaneus remains to be established in Japanese patients. The aim of the present clinical practice-based observational study was to examine the influence of ALN treatment for 1 year on the speed of sound (SOS) of the calcaneus and bone turnover markers in...