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Abstract Duchenne Muscular Dystrophy (DMD) is a progressive muscle disorder caused by genetic mutations of the dystrophin encoding gene. In the absence of functional dystrophin, DMD patients suffer from muscle inflammation and wasting, as well as compromised bone health with increased risk of fracture. The use of high dose glucocorticoids (GC) as the standard therapy also contributes to bone fragility. This study examined the effects of intermittent, daily administered parathyroid hormone (iPTH), an approved bone anabolic therapy, on growing bone and dystrophic muscle in the presence and absence of prednisone treatment using the Mdx mouse model of DMD. Five-weeks of prednisone treatment in Mdx mice decreased cortical bone thickness and area (p < 0.001), with a large increase in endocortical osteoclasts that were significantly improved by PTH treatment (p < 0.001). GC-induced decreases in cortical bone toughness and modulus were improved with iPTH therapy (p < 0.05). Mdx mice showed significantly less bone mass in trabecular compartments of lumbar vertebrae and iPTH treatment, with or without glucocorticoids, significantly improved structural and material properties of this bone. Prednisone improved grip strength and endurance of treadmill running, which were maintained and further improved, respectively, in co-treated Mdx mice. Altogether, our study demonstrates that iPTH therapy significantly ameliorated GC-induced bone loss and maintained or further enhanced the positive effects of GCs on dystrophic muscle function. These findings give insight into the potential for use of teriparatide to treat growing bone in children with DMD. Highlights • Vertebral bone density and toughness are improved by PTH in Mdx mice. • Glucocorticoids decrease cortical bone thickness and toughness are increased by PTH. • PTH treatment decreased inflammatory gene expression in skeletal muscle. • PTH increased type 1 and decreased type 2c skeletal muscle fibers in Mdx mice. [ABSTRACT FROM AUTHOR]

Duchenne muscular dystrophy (DMD) is an X-linked disease of progressive muscle deterioration and weakness. Patients with DMD have poor bone health which is partly due to treatment with glucocorticoids, a standard therapy to prolong muscle function that also induces bone loss. Bisphosphonates are used to treat adults at risk of glucocorticoid-induced osteoporosis but are not currently used in DMD patients until after they sustain fractures. In this study, C57BL/10ScSn-mdx mice, a commonly used DMD animal model, received continuous glucocorticoid, prednisone treatment (0.083 mg/day) from 5 to 10 weeks of age. Pre-treatment with the bisphosphonate pamidronate started at 4 weeks of age over a period of 2 weeks or 6 weeks (cumulative dose 8 mg/kg for both) to assess the effectiveness of the two dosing regimens in ameliorating glucocorticoid-induced bone loss. Mdx mice treated with prednisone had improved muscle function that was not changed by pamidronate treatment. Glucocorticoid treatment caused cortical bone loss and decreased cortical bone strength. Both 2 and 6 week pamidronate treatment increased cortical thickness and bone area compared to prednisone-treated Mdx mice, however, only 2 week pamidronate treatment improved the strength of cortical bone compared to that of glucocorticoid-treated Mdx mice. In the trabecular bone, both pamidronate treatments significantly increased the amount of bone, and increased the ultimate load but not the energy to fail. These results highlight the importance of when and how much bisphosphonate is administered prior to glucocorticoid exposure. [ABSTRACT FROM AUTHOR]

Duchenne muscular dystrophy (DMD) results from genetic mutations of the gene encoding dystrophin, leading to muscle inflammation and degeneration that is typically treated with glucocorticoids. DMD and its treatment with glucocorticoids result in poor bone health and high risk of fractures. Insufficient levels of 25-hydroxyvitamin D (25-hydroxy D) that may contribute to weakened bone are routinely found in DMD patients. To determine the effect of 25-hydroxy D deficiency, this study examined the effects of low vitamin D dietary intake with and without glucocorticoids on the musculoskeletal system of the Mdx mouse model of DMD. At 10 weeks of age, Mdx mice on control diet had low trabecular bone mineral density of distal femurs and lumbar vertebrae with increased osteoclast numbers compared to wild-type mice. Low vitamin D intake resulted in 25-hydroxy D deficiency but had no effect on trabecular or cortical bone. Cortical bone loss and bone weakness were induced by glucocorticoids while they improved muscle grip strength in Mdx mice. 25-hydroxy D deficiency did not result in any significant effects on growing bone or muscle in the Mdx mice. In combination with glucocorticoid treatment, low 25-hydroxy D resulted in no change in cortical bone mineral density but bone ductility was significantly increased suggesting lower bone mineralization. [ABSTRACT FROM AUTHOR]

Glucocorticoids are extensively used to treat patients with Duchenne muscular dystrophy because of their ability to delay muscle damage, prolong ambulation and extend life. However, use of glucocorticoids significantly increases bone loss, fragility and fractures. To determine if antiresorptive bisphosphonates could prevent the effects of glucocorticoids on bone quality, we used dystrophic mdx mice treated with the glucocorticoid prednisone during 8 weeks of rapid bone growth from 5 to 13 weeks of age and treated some mice with the bisphosphonate pamidronate during the first two weeks of prednisone administration. Prednisone reduced long bone growth, decreased cortical bone thickness and area and decreased the strength of the femurs. Pamidronate treatment protected mice from cortical bone loss but did not increase bone strength. The combination of prednisone and pamidronate inhibited remodeling of metaphyseal trabecular bone with large numbers of trabeculae containing remnants of calcified cartilage. Prednisone improved muscle strength in the mdx mice and decreased serum creatine kinase with evidence of improved muscle histology and these effects were maintained in mice treated with pamidronate. [ABSTRACT FROM AUTHOR]

Patients with Duchenne muscular dystrophy are at increased risk of decreased bone mineral density and bone fracture as a result of inactivity. To determine if antiresorptive bisphosphonates could improve bone quality and their effects on muscle we studied the Mdx mouse, treated with pamidronate during peak bone growth at 5 and 6 weeks of age, and examined the outcome at 13 weeks of age. Pamidronate increased cortical bone architecture and strength in femurs with increased resistance to fracture. While overall long bone growth was not affected by pamidronate, there was significant inhibition of remodeling in metaphyseal trabecular bone with evidence of residual calcified cartilage. Pamidronate treatment had positive effects on skeletal muscle in the Mdx mice with decreased serum and muscle creatine kinase and evidence of improved muscle histology and grip strength. [ABSTRACT FROM AUTHOR]

In this paper, a real-time in situ method to detect surface crack initiation on silicon wafers during laser beam irradiation is proposed. This method collects scattered light from the silicon wafer surface subjected to the laser irradiation. When the crack is initiated, the laser beam is strongly scattered by the crack so that the proposed method can monitor the time of crack initiation based on the increases of the level of the scattering signal. In order to demonstrate the performance of this method, a silicon wafer specimen was illuminated by a continuous wave (CW) fiber laser beam (wavelength of 1,070 nm) and the scattered light was detected at three different laser powers. The scattering signal showed a very high level at the time of crack initiation. The detected crack initiation times were 11.6 s, 5.5 s, and 2.5 s at irradiances of 130 W/cm, 149 W/cm, and 168 W/cm, respectively. These results agree well with the theoretical predictions. Based on these results, we demonstrated that the proposed method is very effective for the real-time in situ detection of surface cracking induced by laser beam irradiation on silicon wafers. [ABSTRACT FROM AUTHOR]

Abstract: CD40-activated B (CD40-B) cells might be an attractive source of autologous antigen-presenting cells (APCs) for immunotherapy due to the ability to obtain them from peripheral blood and expand them in vitro. However, soluble IL-4 (sIL-4) in B-cell culture may not represent the “immunological synapse” between B and CD4+ T cells. In this study, the K562 cell line, which expresses CD40L and membrane-bound IL-4 (mbIL-4), could induce higher B-cell proliferation and antigen-presenting surface molecules, including adhesion, costimulatory and HLA molecules, compared with sIL-4. The differentiation to plasmablasts was decreased in CD40-B cells treated with mbIL-4 (CD40-B/mbIL-4) based on flow cytometry analysis. Furthermore, CD40-B/mbIL-4 cells were as potent as mature dendritic cells in the allogeneic lymphocyte reaction and the ability to generate cytotoxic T lymphocytes specific for cytomegalovirus pp65 antigen in vitro. Our results suggest that mbIL-4 could be used to generate CD40-B cells as potent APCs for cellular vaccines and adoptive immunotherapy. [Copyright &y& Elsevier]

Bone cells must constantly respond to hormonal and mechanical cues to change gene expression programs. Of the myriad of epigenomic mechanisms used by cells to dynamically alter cell type-specific gene expression, histone acetylation and deacetylation has received intense focus over the past two decades. Histone deacetylases (HDACs) represent a large family of proteins with a conserved deacetylase domain first described to deacetylate lysine residues on histone tails. It is now appreciated that multiple classes of HDACs exist, some of which are clearly misnamed in that acetylated lysine residues on histone tails is not the major function of their deacetylase domain. Here, we will review the roles of proteins bearing deacetylase domains in bone cells, focusing on current genetic evidence for each individual HDAC gene. While class I HDACs are nuclear proteins whose primary role is to deacetylate histones, class IIa and class III HDACs serve other important cellular functions. Detailed knowledge of the roles of individual HDACs in bone development and remodeling will set the stage for future efforts to specifically target individual HDAC family members in the treatment of skeletal diseases such as osteoporosis. • Our cells bear three main classes of histone deacetylases (HDACs). • Class I HDACs deacetylate histones and regulate chromatin structure. • Class IIa HDACs shuttle between the cytoplasm and the nucleus. • Class III HDACs are NAD+-dependent Sirtuin deacetylases. • Multiple roles of HDACs in skeletal biology are reviewed here. [ABSTRACT FROM AUTHOR]

A novel bacterial strain, named S23T, was isolated from chicken meat of local market in Korea. Cells were Gram-negative, milky-yellow colored, non-motile and coccobacillus. The strain was obligate aerobic and catalase-positive, oxidase-negative, optimum growth temperature and pH were 25 °C and pH 7.0, respectively. On the basis of 16S rRNA gene sequence analysis, strain S23T belongs to the genus Acinetobacter and is most closely related to Acinetobacter defluvii KCTC 52503 T (97.40%). The average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH) value between strain S23T and its closet phylogenetic neighbors was below 76% and 17%, respectively. The G + C content of genomic DNA of strain S23T was 41.53 mol%. The major respiratory quinone was Q-9. The major cellular fatty acids were summed feature 3 (comprising C16:1ω7c and/or C16:1ω6c), C18:1ω9c, and C16:0. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanol-amine, and phosphatidylserine. The ANI and dDDH results and results of the genotypic analysis in combination with chemotaxonomic and physiological data demonstrated that strain S23T represented a novel species within the genus Acinetobacter, for which the name Acinetobacter pullicarnis sp. nov. is proposed. The strain type is S23T (= KACC 19921 T = JCM 33150 T). [ABSTRACT FROM AUTHOR]

Abstract: For the adoptive immunotherapy and the study of cytotoxic T lymphocytes (CTLs) in human, efficient in vitro generation of CTLs is needed. However, it is still difficult to induce T cells specific for naïve antigens in vitro even though dendritic cells (DCs) as potent APCs are used. In this study, we investigated quantitative and qualitative effects of CD4+ T cells during in vitro stimulation of CD8+ T cells from healthy donors using DCs transduced with adenovirus vector expressing human survivin (Adv-survivin). CTLs were not efficiently induced in the absence of CD4+ T cells or in CD25+ depleted CD4+ T cells. When the ratio of CD4+:CD8+ T cells was quantitatively decreased from 2:1 to 1:2, proliferation of CTLs specific for survivin was gradually increased. Because DCs pulsed with HCMV pp65 protein could activate CD4+ T cells to secrete Th1 cytokines, the use of pp65 protein as an adjuvant induced higher numbers and frequencies of CTLs. Furthermore, Th1 conditioning of CD4+ T cells augmented this generation of CTLs. These results suggest that both quantitative and qualitative modulation of CD4+ T cells including the number and Th1 polarization may be required for the efficient induction of CTLs specific for tumor antigens in vitro. [Copyright &y& Elsevier]

Bone formation and resorption are typically coupled, such that the efficacy of anabolic osteoporosis treatments may be limited by bone destruction. The multi-kinase inhibitor YKL-05-099 potently inhibits salt inducible kinases (SIKs) and may represent a promising new class of bone anabolic agents. Here, we report that YKL-05-099 increases bone formation in hypogonadal female mice without increasing bone resorption. Postnatal mice with inducible, global deletion of SIK2 and SIK3 show increased bone mass, increased bone formation, and, distinct from the effects of YKL- 05--099, increased bone resorption. No cell-intrinsic role of SIKs in osteoclasts was noted. In addition to blocking SIKs, YKL-05-099 also binds and inhibits CSF1R, the receptor for the osteoclastogenic cytokine M-CSF. Modeling reveals that YKL-05--099 binds to SIK2 and CSF1R in a similar manner. Dual targeting of SIK2/3 and CSF1R induces bone formation without concomitantly increasing bone resorption and thereby may overcome limitations of most current anabolic osteoporosis therapies. [ABSTRACT FROM AUTHOR]