0
selected
-
1.
Does the Use of a "Walking Bleaching" Technique Increase Bone Resorption Markers?
Bersezio, C, Vildósola, P, Sáez, M, Sánchez, F, Vernal, R, Oliveira, OB, Jorquera, G, Basualdo, J, Loguercio, A, Fernández, E
Operative dentistry. 2018;(3):250-260
Abstract
OBJECTIVE This randomized clinical trial evaluated the effect of 35% hydrogen peroxide in comparison with 37% carbamide peroxide in a nonvital bleaching technique of "walking bleaching" (four sessions of treatment) on periodontal markers: nuclear factor kappa B-ligand (RANK-L-process of root resorption marker) and interleukin 1β (IL-1β-inflammatory response marker). METHODS AND MATERIALS Fifty volunteers presenting with discoloration of nonvital teeth and endodontic treatment in good condition participated. Fifty teeth were randomly divided into two study groups according to bleaching gel: HP = 35% hydrogen peroxide (n=25) and 37% carbamide peroxide (n=25). Nonvital bleaching was performed with a walking bleaching technique consisting of four sessions of bleach application. Gingival crevicular fluid samples were taken in order to quantify the RANK-L and IL-1β levels by enzyme-linked immunosorbent assay. Samples were obtained from six periodontal sites for each bleached tooth: three vestibular and three palatine (mesial, middle, and distal) at seven time periods: baseline, after each of the four sessions of nonvital bleaching, at one week, and at one month after nonvital bleaching. Tooth color variations were analyzed in each session by VITA Bleachedguide 3D-MASTER (ΔSGU). RESULTS Significant increments in the RANK-L and IL-1β levels were detected in each evaluated time compared with baseline ( p<0.05); however, no differences were detected between hydrogen peroxide and carbamide peroxide on increments of the biomarkers studied. The change of color was effective for both nonvital bleaching therapies ( p<0.05). CONCLUSIONS Nonvital bleaching induced a significant increment in the RANK-L and IL-1β levels in periodontal tissues around bleached, nonvital teeth.
-
2.
[Not Available].
Raschle, J
Praxis. 2017;(12):677-678
-
3.
Resorbable bone fixation alloys, forming, and post-fabrication treatments.
Ibrahim, H, Esfahani, SN, Poorganji, B, Dean, D, Elahinia, M
Materials science & engineering. C, Materials for biological applications. 2017;(Pt 1):870-888
Abstract
Metallic alloys have been introduced as biodegradable metals for various biomedical applications over the last decade owing to their gradual corrosion in the body, biocompatibility and superior strength compared to biodegradable polymers. Mg alloys possess advantageous properties that make them the most extensively studied biodegradable metallic material for orthopedic applications such as their low density, modulus of elasticity, close to that of the bone, and resorbability. Early resorption (i.e., <3months) and relatively inadequate strength are the main challenges that hinder the use of Mg alloys for bone fixation applications. The development of resorbable Mg-based bone fixation hardware with superior mechanical and corrosion performance requires a thorough understanding of the physical and mechanical properties of Mg alloys. This paper discusses the characteristics of successful Mg-based skeletal fixation hardware and the possible ways to improve its properties using different methods such as mechanical and heat treatment processes. We also review the most recent work pertaining to Mg alloys and surface coatings. To this end, this paper covers (i) the properties and development of Mg alloys and coatings with an emphasis on the Mg-Zn-Ca-based alloys; (ii) Mg alloys fabrication techniques; and (iii) strategies towards achieving Mg-based, resorbable, skeletal fixation devices.
-
4.
Plyometric exercise and bone health in children and adolescents: a systematic review.
Gómez-Bruton, A, Matute-Llorente, Á, González-Agüero, A, Casajús, JA, Vicente-Rodríguez, G
World journal of pediatrics : WJP. 2017;(2):112-121
Abstract
BACKGROUND Many jumping interventions have been performed in children and adolescents in order to improve bone-related variables and thus, ensure a healthy bone development during these periods and later in life. This systematic review aims to summarize and update present knowledge regarding the effects that jumping interventions may have on bone mass, structure and metabolism in order to ascertain the efficacy and durability (duration of the effects caused by the intervention) of the interventions. DATA SOURCES Identification of studies was performed by searching in the database MEDLINE/PubMed and SportDiscus. Additional studies were identified by contacting clinical experts and searching bibliographies and abstracts. Search terms included "bone and bones", "jump*", "weight-bearing", "resistance training" and "school intervention". The search was conducted up to October 2014. Only studies that had performed a specific jumping intervention in under 18-year olds and had measured bone mass were included. Independent extraction of articles was done by 2 authors using predefined data fields. RESULTS A total of 26 studies were included in this review. Twenty-four studies found positive results as subjects included in the intervention groups showed higher bone mineral density, bone mineral content and bone structure improvements than controls. Only two studies found no effects on bone mass after a 10-week and 9-month intervention. Moreover, those studies that evaluated the durability of the effects found that some of the increases in the intervention groups were maintained after several years. CONCLUSIONS Jumping interventions during childhood and adolescence improve bone mineral content, density and structural properties without side effects. These type of interventions should be therefore implemented when possible in order to increase bone mass in early stages of life, which may have a direct preventive effect on bone diseases like osteoporosis later in life.
-
5.
Effects of high-protein intake on bone turnover in long-term bed rest in women.
Heer, M, Baecker, N, Frings-Meuthen, P, Graf, S, Zwart, SR, Biolo, G, Smith, SM
Applied physiology, nutrition, and metabolism = Physiologie appliquee, nutrition et metabolisme. 2017;(5):537-546
-
-
Free full text
-
Abstract
Bed rest (BR) causes bone loss, even in otherwise healthy subjects. Several studies suggest that ambulatory subjects may benefit from high-protein intake to stimulate protein synthesis and to maintain muscle mass. However, increasing protein intake above the recommended daily intake without adequate calcium and potassium intake may increase bone resorption. We hypothesized that a regimen of high-protein intake (HiPROT), applied in an isocaloric manner during BR, with calcium and potassium intake meeting recommended values, would prevent any effect of BR on bone turnover. After a 20-day ambulatory adaptation to a controlled environment, 16 women participated in a 60-day, 6° head-down-tilt (HDT) BR and were assigned randomly to 1 of 2 groups. Control (CON) subjects (n = 8) received 1 g/(kg body mass·day)-1 dietary protein. HiPROT subjects (n = 8) received 1.45 g protein/(kg body mass·day)-1 plus an additional 0.72 g branched-chain amino acids per day during BR. All subjects received an individually tailored diet (before HDTBR 1888 ± 98 kcal/day; during HDTBR 1604 ± 125 kcal/day; after HDTBR 1900 ± 262 kcal/day), with the CON group's diet being higher in fat and carbohydrate intake. High-protein intake exacerbated the BR-induced increase in bone resorption marker C-telopeptide (>30%) (p < 0.001) by the end of BR. Bone formation markers were unaffected by BR and high-protein intake. We conclude that high-protein intake in BR might increase bone loss. Further long-duration studies are mandatory to show how the positive effect of protein on muscle mass can be maintained without the risk of reducing bone mineral density.
-
6.
Calcium Supplementation Attenuates Disruptions in Calcium Homeostasis during Exercise.
Sherk, VD, Wherry, SJ, Barry, DW, Shea, KL, Wolfe, P, Kohrt, WM
Medicine and science in sports and exercise. 2017;(7):1437-1442
-
-
Free full text
-
Abstract
UNLABELLED An exercise-induced decrease in serum ionized calcium (iCa) is thought to trigger an increase in parathyroid hormone (PTH), which can stimulate bone resorption. PURPOSE The purpose of this study was to determine whether taking a chewable calcium (Ca) supplement 30 min before exercise mitigates disruptions in Ca homeostasis and bone resorption in competitive male cyclists. METHODS Fifty-one men (18 to 45 yr old) were randomized to take either 1000 mg Ca (CA) or placebo (PL) 30 min before a simulated 35-km cycling time trial. Serum iCa and PTH were measured before and immediately after exercise and a marker of bone resorption (C-terminal telopeptide of type I collagen) was measured before and 30 min after exercise. RESULTS Serum iCa decreased in both groups from before to after exercise (mean ± SD, CA = 4.89 ± 0.16 to 4.76 ± 0.11 mg·dL, PL = 4.92 ± 0.15 to 4.66 ± 0.22 mg·dL, both P ≤ 0.01); the decrease was greater (P = 0.03) in the PL group. There was a nonsignificant (P = 0.07) attenuation of the increase in PTH by Ca supplementation (CA = 30.9 ± 13.0 to 79.7 ± 42.6 pg·mL, PL = 37.1 ± 14.8 to 111.5 ± 49.4 pg·mL, both P ≤ 0.01), but no effect of Ca on the change in C-terminal telopeptide of type I collagen, which increased in both groups (CA = 0.35 ± 0.17 to 0.50 ± 0.21 ng·mL, PL = 0.36 ± 0.13 to 0.54 ± 0.22 ng·mL, both P ≤ 0.01). CONCLUSION It is possible that ingesting Ca only 30 min before exercise was not a sufficient time interval to optimize gut Ca availability during exercise. Further studies will be needed to determine whether adequate Ca supplementation before and/or during exercise can fully mitigate the exercise-induced decrease in serum iCa and increases in PTH and bone resorption.
-
7.
[Calciuria as a metabolic marker for various conditions and diseases].
Egshatyan, LV, Mokrysheva, NG
Urologiia (Moscow, Russia : 1999). 2017;(5):132-138
Abstract
The article analyzes the literature on the features of human calcium homeostasis. The authors describe the etiopathogenetic role of calcitropic hormones, the plasma and urine acid-base status, various ions, lifestyle and nutrition and other factors contributing to hypercalciuria due to increased intestinal absorption, bone resorption, impairment of tubular calcium reabsorption, etc. They discuss the role of calciuria as a factor in forming urinary calculi and present their own observations.
-
8.
Bone health nutraceuticals alter microarray mRNA gene expression: A randomized, parallel, open-label clinical study.
Lin, Y, Kazlova, V, Ramakrishnan, S, Murray, MA, Fast, D, Chandra, A, Gellenbeck, KW
Phytomedicine : international journal of phytotherapy and phytopharmacology. 2016;(1):18-26
Abstract
BACKGROUND AND OBJECTIVE Dietary intake of fruits and vegetables has been suggested to have a role in promoting bone health. More specifically, the polyphenols they contain have been linked to physiological effects related to bone mineral density and bone metabolism. In this research, we use standard microarray analyses of peripheral whole blood from post-menopausal women treated with two fixed combinations of plant extracts standardized to polyphenol content to identify differentially expressed genes relevant to bone health. METHODS In this 28-day open-label study, healthy post-menopausal women were randomized into three groups, each receiving one of three investigational fixed combinations of plant extracts: an anti-resorptive (AR) combination of pomegranate fruit (Punica granatum L.) and grape seed (Vitis vinifera L.) extracts; a bone formation (BF) combination of quercetin (Dimorphandra mollis Benth) and licorice (Glycyrrhiza glabra L.) extracts; and a fixed combination of all four plant extracts (AR plus BF). Standard microarray analysis was performed on peripheral whole blood samples taken before and after each treatment. Annotated genes were analyzed for their association to bone health by comparison to a gene library. RESULTS The AR combination down-regulated a number of genes involved in reduction of bone resorption including cathepsin G (CTSG) and tachykinin receptor 1 (TACR1). The AR combination also up-regulated genes associated with formation of extracellular matrix including heparan sulfate proteoglycan 2 (HSPG2) and hyaluronoglucosaminidase 1 (HYAL1). In contrast, treatment with the BF combination resulted in up-regulation of bone morphogenetic protein 2 (BMP-2) and COL1A1 (collagen type I α1) genes which are linked to bone and collagen formation while down-regulating genes linked to osteoclastogenesis. Treatment with a combination of all four plant extracts had a distinctly different effect on gene expression than the results of the AR and BF combinations individually. These results could be due to multiple feedback systems balancing activities of osteoblasts and osteoclasts. CONCLUSION In summary, this ex-vivo microarray study indicated that the pomegranate, grape seed, quercetin and licorice combinations of plant extracts modulated gene expression for both osteoclastic and osteogenic processes.
-
9.
[Bone and Nutrition. Effect of isoflavones on bone health].
Ishimi, Y
Clinical calcium. 2015;(7):999-1005
Abstract
Effects of isoflavones on bone health in postmenopausal women are expected, since it shows weak estrogenic activity. In the observational study in Asia, association between intake of soy foods or isoflavone and bone mineral density and fracture prevention has been observed. In the meta-analysis of intervention trials of isoflavone in 60 years or less of postmenopausal women, 75 mg by day about 6 months to 1 year intervention of isoflavones induced suppression of significant decline of bone resorption markers in the urine was observed. On the other hand, intended for Westerners women in the study intervened isoflavones with calcium and vitamin D simultaneously, it is not observed effectiveness of isoflavones on the bone. Such a difference might be due to diversity in the individual metabolic capacity for isoflavones as well as the effects of presence or absence of other co-interventions nutrients.
-
10.
Denosumab for low bone mass in hemodialysis patients: a noncontrolled trial.
Hiramatsu, R, Ubara, Y, Sawa, N, Hoshino, J, Hasegawa, E, Kawada, M, Imafuku, A, Sumida, K, Mise, K, Hayami, N, et al
American journal of kidney diseases : the official journal of the National Kidney Foundation. 2015;(1):175-7