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3262. Bone marrow necrosis: a rare complication of herbal treatment with Hypericum perforatum (St. John´s wort)
- Creator:
- Demiroglu, Yusuf Ziya
- Type:
- model:article and TEXT
- Language:
- English
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3263. Bone marrow-derived cells participate in composition of the satellite cell niche in intact and regenerating mouse skeletal muscle
- Creator:
- Čížková, D., Komárková, Z., Bezrouk, A., Macháčková, L., Vávrová, J., Filip, S., and Mokrý, J.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- satellite cells, bone marrow cells, satellite cell niche, transplantation, and skeletal muscle regeneration
- Language:
- English
- Description:
- The cellular components of the satellite cell niche participate in the regulation of skeletal muscle regeneration. Beside myogenic cells at different developmental stages, this niche is formed by cells of the immune system, the interstitial connective tissue and the vascular ystem. Unambiguous determination of the origin of these cell types could contribute to optimization of the cell-based therapy of skeletal muscle disorders. In our work, we intravenously transplanted mouse GFP+ unseparated bone marrow cells into whole-body lethally irradiated immunocom-petent mice four weeks before cardiotoxin-induced injury of the recipients’ skeletal muscles. Seven and 28 days after the toxin injection, the injured regenerating and contralateral intact muscles were examined for identification of GFP+ bone marrow-derived cells by direct fluorescence, protein immunohistochemistry and immunogold transmission electron microscopy. In both the intact and injured muscles, GFP positivity was determined in immune cells, mainly in macrophages, and in interstitial spindle-shaped cells. Moreover, in the injured muscles, rare GFP+ endothelial cells of the blood vessels and newly formed myotubes and muscle fibres were present. Our results confirmed the ability of bone marrow-derived cells to contribute to the cellular component of the satellite cell niche in the intact and regenerating skeletal muscle. These cells originated not only from haematopoietic stem cells, but obviously also from other stem or progenitor cells residing in the bone marrow, such as multipotent mesenchymal stromal cells and endothelial progenitors. and Corresponding author: Dana Čížková
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3264. Bone metabolism: a note on the significance of mouse models
- Creator:
- Raška, O., Klára Bernášková, and Ivan Raška
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, kostní metabolismus, osteoklasty, osteoporóza, obezita, diabetes mellitus, bone metabolism, osteoclasts, osteoporosis, obesity, bone remodeling, osteoblast, osteocalcin, 14, and 612
- Language:
- English
- Description:
- This minireview briefly surveys the complexity of regulations governing the bone metabolism. The impact of clinical studies devoted to osteoporosis is briefly summarized and the emphasis is put on the significance of experimental mouse models based on an extensive use of genetically modified animals. Despite possible arising drawbacks, the studies in mice are of prime importance for expanding our knowledge on bone metabolism. With respect to human physiology and medicine, one should be always aware of possib le limitations as the experimental results may not be, or may be only to some extent, transposed to humans. If applicable to humans, results obtained in mice provide new clues for assessing un foreseen treatment strategies for patients. A recent publication representing in our opinion the important breakthrough in the field of bone metabolism in mice is commented in detail. It provides an evidence that skeleton is endocrine organ that affects energy metabolism and osteocalcin, a protein specifically synthesized and secreted by osteoblasts, is a hormone involved. If confirmed by other groups and applicable to humans, this study provides the awaited connection of long duration between bone disorders on one hand and obesity and diabetes on the other., O. Raška, K. Bernášková, I. Raška Jr., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3265. Bone microstructure of mice after prolonged taurine treatment
- Creator:
- Martiniakova, M. , Sarocka, A., Babosova, R. , Galbavy, D. , Kapusta, E., Goc, Z., Formicki, G. , and Omelka, R.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- taurine, bone, mouse, and microstructure
- Language:
- English
- Description:
- Taurine, a sulphur - containing amino acid, has been termed a functional nutrient. Its synthetic form is a common ingredient in supplements and energy drinks. There is no information concerning taurine impact on bone microstructure after prolonged supplemental use. Also, differences in bone parameters of mice following taurine exposure are unknown. In this study, a detailed microstructure of compact and trabecular bone tissues of mice subchronically exposed to taurine was determined. Animals (n=12) were segregated into three groups: E1 group – mice received 20 mg/kg b.w. of taurine per day during 8 weeks; E2 group – mice were fed by taurine at a dose of 40 mg/kg b.w. for 8 weeks and a control (C) group. Decreased density of secondary osteons, increased sizes of primary osteon's vascular canals (P<0.05) were observed in taurine – treated animals. Cortical bone thickness, trabecular thickness were decreased (P<0.05) in E1 group, and relative volume of trabecular bone was lower (P<0.05) in E2 group as compared to C group. According to our results, prolonged taurine exposure at the doses used in this study can negatively affect both compact and trabecular bone tissues microstructure.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3266. Bone mineral density and body composition in men with multiple sclerosis chronically treated with low-dose glucocorticoids
- Creator:
- Vít Zikán, Michaela Týblová, Ivan Raška, Eva Havrdová, Luchavová, M., Dana Michalská, and Aleš Kuběna
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, bone mineral density, body composition, multiple sclerosis, osteoporosis, glucocorticoid treatment, 14, and 612
- Language:
- English
- Description:
- The aim of the study was to compare the bone mineral density (BMD) and body composition between ambulatory male MS patients and control subjects and to evaluate the relationships among body composition, motor disability, glucocorticoids (GC) use, and bone health. Body composition and BMD were measured by dual-energy X-ray absorptiometry in 104 ambulatory men with MS (mean age: 45.2 years) chronically treated with low-dose GC and in 54 healthy age-matched men. Compared to age-matched controls, MS patients had a significantly lower total body bone mineral content (TBBMC) and BMD at all measured sites except for the radius. Sixty five male MS patients (62.5 %) met the criteria for osteopenia and twenty six of them (25 %) for osteoporosis. The multivariate analysis showed a consistent dependence of bone measures (except whole body BMD) on BMI. The total leg lean mass % was as an independent predictor of TBBMC. The Expanded Disability Status Scale (EDSS), cumulative GC dose and age were independent determinants for BMD of the proximal femur. We conclude that decreasing mobility in male MS patients is associated with an increasing degree of osteoporosis and muscle wasting in the lower extremities. The chronic low-dose GC treatment further contributes to bone loss., V. Zikán ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3267. Bone mineral density in patients with apolipoprotein E type 2/2 and 4/4 genotype
- Creator:
- Tomáš Štulc, Richard Češka, Aleš Hořínek, and Jan Štěpán
- Format:
- print, bez média, and svazek
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, osteoporóza, vitamin K, osteoporosis, bone mineral density, bone turnover, apolipoprotein E, 14, and 612
- Language:
- English
- Description:
- The peak bone mass and the rate of bone loss are in part genetically determined. It has been suggested that bone mineral density (BMD) may be related to allelic variation in the apolipoprotein E (ApoE) gene locus. ApoE is important in the receptor-mediated clearance of chylomicron particles from the plasma, Apo E4 having the highest and Apo E2 the lowest receptor affinity. Chylomicrons are the main carrier of vitamin K in the plasma; vitamin K plays an important role in the carboxylation of osteocalcin. We have tested the hypothesis that persons with E4 variant would have lower BMD and increased bone turnover than those with E2 variant. A total of 18 ApoE 2/2 and ApoE 4/4 homozygotes were selected from 873 patients who were examined for the ApoE genotype. BMD in lumbar vertebral, femoral neck and distal forearm was measured and plasma concentrations of osteocalcin and C-terminal fragments of collagen (CTx) were determined. BMD values (expressed as T-score) at the three specified sites were -0.12± 1.72, -0.52± 1.32 and -0.52± 0.81 in ApoE 2/2 group and -0.24± 1.22, 0.00± 0.84 and -0.17± 1.07 in the ApoE 4/4 group. Plasma osteocalcin and CTx were within normal limits in both groups. In conclusion, we did not observe any association of ApoE genotype with BMD and biochemical markers of bone metabolism in ApoE 2/2 and ApoE 4/4 homozygotes., T. Štulc, R. Češka, A. Hořínek, J. Štěpán., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3268. Bone remodeling, particle disease and individual susceptibility to periprosthetic osteolysis
- Creator:
- Jiří Gallo, Milan Raška, František Mrázek, and Martin Petřek
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Experimentální medicína, patologická fyziologie, osteoklasty, ortopedie, pathological physiology, osteoclasts, orthopedics, periprotetická osteolýza, osteoblast, periprosthetic osteolysis, particle disease, basic multicellular unit, 14, and 616-092
- Language:
- English
- Description:
- Bone remodeling is a tightly coupled process consisting of repetitive cycles of bone resorption and formation. Both processes are governed by mechanical signals, which operate in conjunction with local and systemic factors in a discrete anatomic structure designated a basic multicellular unit (BMU). The microenvironment around total joint arthroplasty is a dynamic and complex milieu influenced by the chemical and physical stimuli associated with servicing the prosthesis. A key factor limiting the longevity of the prosthesis is polyethylene wear, which induces particle disease, and this may lead to increased and prolonged activity of BMUs resulting in periprosthetic osteolysis. Several pathways regulating BMU function have been reported in the past, including RANKL/RANK/OPG/TRAF6, TNF-α/TNFR/TRAF1, and IL-6/CD126/JAK/STAT. Moreover, the expression and functional activity of all these molecules can be affected by variations in their genes. These may explain the differences in severity of bone defects or prosthetic failure between patients with similar wear rates and the same prosthesis. Simultaneously, this data strongly support the theory of individual susceptibility to prosthetic failure., J. Gallo, M. Raška, F. Mrázek, M. Petřek., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3269. Bone response to loading in mice with targeted disruption of the cartilage oligomeric matrix protein gene
- Creator:
- Sengul, A., Mohan, S., and Kesavan, C.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, mechanical loading, COMP, gene expression, BMD, mice, 14, and 612
- Language:
- English
- Description:
- Exercise induced bone response although established, little is known about the molecular components that mediate bone response to mechanical loading (ML). In our recent QTL study, we identified one such possible molecular component responding to ML: cartilage oligomeric matrix protein (COMP). To address the COMP role in mediating ML effects on bone formation, COMP expression was evaluated as a function of duration and age in response to ML in female B6 mice. A 9N load was applied using a four-point bending device at 2Hz frequency for 36 cycles, once per day for 2-, 4- and 12-days on the right tibia. The left tibia was used as an internal control. Loading caused an increase in COMP expression by 1.3-, 2- and 4-fold respectively after 2-, 4- and 12-days of loading. This increase was also seen in 16 and 36-week old mice. Based on these findings, we next used COMP knockout (KO) mice to evaluate the cause and effect relationship. Quantitative analysis revealed 2 weeks of ML induced changes in vBMD and bone size in the KO mice (5.9 % and 21 % vs. unloaded bones) was not significantly different from control mice (7 % and 24 % vs. unloaded bones). Our results imply that COMP is not a key upstream mediator of the anabolic effects of ML on the skeleton., A. Sengul, S. Mohan, C. Kesavan., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3270. Bone tissue as a systemic endocrine regulator
- Creator:
- Ivana Žofková
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, inkretiny, testosteron, incretins, testosterone, bone morphogenetic peptide, angiotensin, osteocalcin, phosphatonins, phosphate homeostasis, FGF23, chronic kidney diseases, klotho-α, male reproduction, 14, and 612
- Language:
- English
- Description:
- Bone is a target tissue for hormones, such as the sex steroids, parathormon, vitamin D, calcitonin, glucocorticoids, and thyroid hormones. In the last decade, other “non-classic” hormones that modulate the bone tissue have been identified. While incretins (GIP and GLP-1) inhibit bone remodeling, angiotensin acts to promote remodeling. Bone morphogenetic protein (BMP) has also been found to have anabolic effects on the skeleton by activating bone formation during embryonic development, as well as in the postnatal period of life. Bone has also been identified as an endocrine tissue that produces a number of hormones, that bind to and modulate extra-skeletal receptors. Osteocalcin occupies a central position in this context. It can increase insulin secretion, insulin sensitivity and regulate metabolism of fatty acids. Moreover, osteocalcin also influences phosphate metabolism via osteocyte-derived FGF23 (which targets the kidneys and parathyroid glands to control phosphate reabsorption and metabolism of vitamin D). Finally, osteocalcin stimulates testosterone synthesis in Leydig cells and thus may play some role in male fertility. Further studies are necessary to confirm clinically important roles for skeletal tissue in systemic regulations., I. Zofkova., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public