{"title":"[Effects of antiresorptive therapy on the structural and material properties of bone strength].","authors":"Hideaki Kishimoto","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Bone strength depends on its structural and material properties. Structural properties are determined by the size and shape of bone and also the microarchitecture. Material properties are determined by mineral crystallinity, collagen structure and microdamage in bone. The strength of bone is adapted to the needs of physical activities by biologic mechanisms, bone modeling and remodeling. The deterioration of bone strength in postmenopausal women is characterized by a trabecular bone deficit with poor trabecular connectivity and followed by a cortical bone deficit with trabeculation of endocortical bone and intracortical porosity due to accelerated bone remodeling. In high turnover osteoporosis antiresorptive therapy is effective in preventing the structural deficit and in increasing the stiffness and the toughness(bone strength)by increasing the mean degree of mineralization of bone tissue through the prolongation of secondary mineralization. But the long-term use of strong antiresorber, i.e. bisphosphonate or denosumab, would result in highly mineralized bone and disturbed repair of microcracks by inhibition of bone remodeling. Intermittent use or discontinuation of strong antiresorber after about 3-5 years of administration could be recommended to avoid the deterioration of bone strength.</p>","PeriodicalId":502100,"journal":{"name":"Clinical calcium","volume":"26 1","pages":"107-15"},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145351222","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"[Topics for translational research].","authors":"Atsushi Suzuki","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>This report focused on translational research presented in ASBMR 2015 held in Seattle, WA in October 2015. Comorbidity with chronic diseases such as diabetes and chronic kidney disease and the relationship between skeletal and extraskeltal tissues give us more complexed pathophysiological issues to be clarified in superaged society.</p>","PeriodicalId":502100,"journal":{"name":"Clinical calcium","volume":"26 1","pages":"136-8"},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145351235","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"[Radiological assessment of bone quality].","authors":"Masako Ito","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Structural property of bone includes micro- or nano-structural property of the trabecular and cortical bone, and macroscopic geometry. Radiological technique is useful to analyze the bone structural property;micro-CT or synchrotron-CT is available to analyze micro- or nano-structural property of bone samples ex vivo, and multi-detector row CT(MDCT)or high-resolution peripheral QCT(HR-pQCT)is available to analyze human bone in vivo. For the analysis of hip geometry, CT-based hip structure analysis(HSA)is available aw sell se radiography and DXA-based HSA. These structural parameters are related to biomechanical property, and these assessment tools provide information of pathological changes or the effects of anti-osteoporotic agents on bone.</p>","PeriodicalId":502100,"journal":{"name":"Clinical calcium","volume":"26 1","pages":"49-56"},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145351237","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"[Epidemiology of respiratory diseases and osteoporosis.]","authors":"Saeko Fujiwara","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>A large scale of epidemiological studies demonstrated that osteoporosis risk was about 1.5 times higher and fracture risk was 1.2-1.8 times higher among COPD patients. In COPD, risk factors for fracture have been reported to be severity of the COPD and use of bronchodilator in addition to ordinal risk factors for the fracture such as age, previous fracture, smoking, usage of glucocorticoid and others. There were inconsistent results of the relationship between sleep apnea and low bone mass. The relationship was found between sleep apnea and fall and non-spin fracture risk.</p>","PeriodicalId":502100,"journal":{"name":"Clinical calcium","volume":"26 10","pages":"1387-1392"},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145351122","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"[Pharmacokinetics of bisphosphonate.]","authors":"Midori Nakamura, Masanori Koide, Nobuyuki Udagawa","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The objective of treating osteoporosis is to prevent fractures. Bisphosphonates inhibit bone resorption and increase bone density, thereby suppressing the occurrence of fractures. Bisphosphonates have a high affinity for hydroxyapatite. About 20-80%of bisphosphonates absorbed in vivo is adsorbed onto the bone surface. However, the absorption rates of orally ingested bisphosphonates are less than 1%. Bisphosphonates adhered to the bone surface are specifically incorporated into cells upon bone resorption by osteoclasts. Thus, the cytoskeleton of osteoclasts is destroyed, and apoptosis is induced to suppress bone resorption. This article overviews the mechanisms of action and pharmacokinetics of bisphosphonates.</p>","PeriodicalId":502100,"journal":{"name":"Clinical calcium","volume":"26 11","pages":"1561-1570"},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145351135","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"[Response to mechanical stimulus and cardiovascular homeostasis.]","authors":"Ken Takahashi, Keiji Naruse","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Response to mechanical stimulus, including blood pressure regulation as a typical example, is essential for cardiovascular homeostasis. Traditionally, mechanism of blood pressure regulation can be divided into two categories:short term neural regulation via arterial baroreceptor reflex and long term humoral regulation via renin-angiotensin system. Recent studies have revealed that sensitivity of baroreceptor reflex is impaired in metabolic syndrome and aging. Moreover, it is suggested that the baroreceptor reflex is involved in long term blood pressure regulation. This review introduces the mechanism of mechanotransduction in the baroreceptor reflex.</p>","PeriodicalId":502100,"journal":{"name":"Clinical calcium","volume":"26 12","pages":"1671-1676"},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145351157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"[Smoking & Bone.]","authors":"Reiko Watanabe, Daisuke Inoue","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Smoking is associated with decreased bone mineral density(BMD)and increased fracture risk. Conversely, smoking cessation results in BMD gain and decreased fracture risk, suggesting that smoking-induced bone metabolic changes are partially reversible. However, the mechanism of bone fragility induced by smoking is unknown. Meta-analyses have shown that aberrant PTH-vitamin D axis may affect bone metabolism in smokers. Previous animal studies have also reveled that nicotine, one of the major toxic substances of cigarettes, negatively regulates bone formation. This brief review will summarize recent studies on the effects of smoking on bone metabolism, including our recent results evaluating bone metabolic changes after smoking cessation.</p>","PeriodicalId":502100,"journal":{"name":"Clinical calcium","volume":"26 10","pages":"1445-1450"},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145351181","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"[Physiolgically-based pharmacokinetics:Theory and examples.]","authors":"Takahiro Ishimoto, Yukio Kato","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Pharmacological outcome and a certain side effects of therapeutic drugs generally depend on concentration of the drugs and/or their active metabolites in the body. Physiologically-based pharmacokinetics is quantitative tool to understand the drug concentration in the body. Drug efficacy is sometimes affected by subjective factors and cannot be clearly quantified. Even in such cases, it could be possible to quantitatively understand possible pharmacological events occurred in the patients by understanding pharmacokinetics of the corresponding drug. Here, we have attempted to summarize the basis of physiologically-based pharmacokinetics to understand which factors will determine drug concentration in the body and how to predict/speculate the drug concentration in the body in a quantitative manner. For easier understanding by the readers, we introduce some examples of pharmacokinetic property of several osteoporosis drugs.</p>","PeriodicalId":502100,"journal":{"name":"Clinical calcium","volume":"26 11","pages":"1529-1537"},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145351207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"[Effect of impaired tissue function on pharmacokinetics of anti-osteoporotic drugs.]","authors":"Tatsuo Takahashi","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>It is necessary to achieve pharmacotherapy appropriate to individual patient with respect to effectiveness and safety. Since drugs are given to patients with various kinds of diseases and conditions, in which pharmacokinetics greatly changes, we need to understand the relationship between pharmacokinetics and patient's condition, minimizing the individual differences in drug efficacy and toxicity. In this report, I outline the alteration of pharmacokinetics of anti-osteoporotic drugs in patients with various diseases and conditions.</p>","PeriodicalId":502100,"journal":{"name":"Clinical calcium","volume":"26 11","pages":"1539-1545"},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145351213","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"[Mechanical strength and mechano-compatibility of tissue-engineered bones].","authors":"Shigeo Tanaka","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Current artificial bones made of metals and ceramics may be replaced around a decade after implantation due to its low durability, which is brought on by a large difference from the host bone in mechanical properties, i.e., low mechano-compatibility. On the other hand, tissue engineering could be a solution with regeneration of bone tissues from stem cells in vitro. However, there are still some problems to realize exactly the same mechanical properties as those of real bone. This paper introduces the technical background of bone tissue engineering and discusses possible methods for installation of mechano-compatibility into a regenerative bone. At the end, future directions toward the realization of ideal mechano-compatible regenerative bone are proposed.</p>","PeriodicalId":502100,"journal":{"name":"Clinical calcium","volume":"26 1","pages":"93-8"},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145351273","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}