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Purpose To propose hybrid predicting models integrating clinical and magnetic resonance imaging (MRI) features to diagnose lumbar vertebral osteopenia (LvOPI) in premenopausal women. Methods This prospective study enrolled 101 Taiwanese women, including 53 before and 48 women after menopause. Clinical information, including age, body height, body weight and body mass index (BMI), were recorded. Bone mineral density (BMD) was measured by the dual-energy X-ray absorptiometry. Lumbar vertebral fat fraction (LvFF) was measured by MRI. LvOPI scores (LvOPISs) comprising different clinical features and LvFF were constructed to diagnose LvOPI. Statistical analyses included normality tests, linear regression analyses, logistic regression analyses, group comparisons, and diagnostic performance. A P value less than 0.05 was considered as statistically significant. Results The post-menopausal women had higher age, body weight, BMI, LvFF and lower BMD than the pre-menopausal women (all P P P P = 0.0566), BMI (0.737; P P P P Conclusion The diagnostic accuracy of the LvOPI can be improved by using our proposed hybrid predicting models in Taiwanese premenopausal women.

The most critical factor for fracture union is the blood supply to the fracture site, which is usually impaired in patients with diabetes. Recently, mesenchymal stem cells-derived conditioned medium (MSC-CM) has shown significantly higher levels of angiogenic factors, such as VEGF and IL-6. We demonstrate in this report that MSC-CM delivered in gelatin sponges stimulates angiogenesis and promotes fracture healing in a diabetic rat model. Subcutaneous implantation of gelatin sponges soaked in MSC-CM demonstrated better tissue ingrowth and higher capillary densities at 2 and 3 weeks than gelatin sponges in minimal essential medium (MEM) or 293 cell-derived conditioned medium (293-CM). Implantation of fibular defects with gelatin sponges soaked in MSC-CM enhanced bone ingrowth and fracture healing rates compared to 293-CM and MEM groups at 8 weeks. Micro-computed tomography analysis further indicated a higher new bone volume in the MSC-CM group compared to the other diabetic groups. Histological analysis with CD31 immunostaining also revealed that MSC-CM increased endothelial cell counts compared to the other groups. Together, these results indicated that gelatin sponges used to deliver MSC-CM promote angiogenesis and fracture healing in a diabetic model and may be an alternative strategy for treating fracture non-union in patients with diabetes. Copyright © 2011 John Wiley & Sons, Ltd.

FT-IR spectra of the co-adsorption of benzene and CO have been performed to identify the preferred adsorption sites of hydrogen and benzene on a Pt/SiO2 catalyst for hydrogenation of benzene. Results of CO adsorbed on atop sites on Pt/SiO2 includes: an α peak at 2091 cm−1, a β peak at 2080 cm−1 and a γ peak at 2067 cm−1 indicating three kinds of adsorption sites for dissociative hydrogen on Pt/SiO2. The site of lowest CO stretching frequency offers stronger adsorbates–metal interaction for benzene and hydrogen. Hydrogen binding on the site of lowest CO stretching frequency before benzene adsorption significantly enhances the reaction rate of benzene hydrogenation.

Structural and electrochemical studies have been carried out on LiNi0.8Co0.17Al0.03O2 cathode material. X-ray diffraction refinement results confirmed that the material is in a pure phase having a layered structure. The electrochemical study on LiNi0.8Co0.17Al0.03O2 shows high specific discharge capacity with good cycle life upon different charge-discharge. In situ X-ray absorption near edge structure analysis confirmed the transformation of Ni state from Ni3+ to Ni4+ during the delithiation process without affecting the valency of Co. The electrochemical results revealed that the doping of Co3+ and Al3+ stabilized the layered structure considerably during delithiation process.

The novel intermetallic deuteride YMn 2 D 6 was synthesized under high deuterium pressure. In order to identify the structure and characterize the magnetic properties of this deuteride the powder X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), Mn X-ray absorption near edge structure (XANES) and magnetization measurement (SQUID) were carried out. The crystal structure, the chemical state of Mn and the magnetic properties of this novel deuteride were examined and discussed. It should be noted that the structure of YMn 2 D 6 ( F -43 m ) differs dramatically from C15 symmetry of the parent material. Such a great rearrangement of the metal lattice due to deuterium absorption is rather exceptional for C15 Laves phase.

The most critical factor for fracture union is the blood supply to the fracture site, which is usually impaired in patients with diabetes. Recently, mesenchymal stem cells-derived conditioned medium (MSC-CM) has shown significantly higher levels of angiogenic factors, such as VEGF and IL-6. We demonstrate in this report that MSC-CM delivered in gelatin sponges stimulates angiogenesis and promotes fracture healing in a diabetic rat model. Subcutaneous implantation of gelatin sponges soaked in MSC-CM demonstrated better tissue ingrowth and higher capillary densities at 2 and 3 weeks than gelatin sponges in minimal essential medium (MEM) or 293 cell-derived conditioned medium (293-CM). Implantation of fibular defects with gelatin sponges soaked in MSC-CM enhanced bone ingrowth and fracture healing rates compared to 293-CM and MEM groups at 8 weeks. Micro-computed tomography analysis further indicated a higher new bone volume in the MSC-CM group compared to the other diabetic groups. Histological analysis with CD31 immunostaining also revealed that MSC-CM increased endothelial cell counts compared to the other groups. Together, these results indicated that gelatin sponges used to deliver MSC-CM promote angiogenesis and fracture healing in a diabetic model and may be an alternative strategy for treating fracture non-union in patients with diabetes.

Biomaterials not only serve as scaffolds for bone regeneration, but may also exhibit inductive capability for bone growth. The goal of this study was to identify the best extracellular matrix protein for enhancing osteogenesis by hMSCs (human mesenchymal stem cells) and to investigate the underlying mechanism. Coating with collagen I, but not fibronectin, laminin, gelatin, and poly-L-lysine, enhanced late cell proliferation and promoted osteogenesis by hMSCs, as evidenced by an increase in Alizarin Red S staining, alkaline phosphatase activity and mRNA levels of Runx2 and osteocalcin. Coating with collagen I induced activation of ERK and Akt but not FAK, and treatment with PD98059 and LY294002 blocked the activation of ERK and Akt, respectively. Interestingly, LY294002 also blocked ERK activation, indicating the activation of PI3K/ERK pathway upon contact with collagen I. Furthermore, PD98059 or LY294002 abolished collagen I-induced promotion of osteogenesis by hMSCs. However, blocking antibodies against alpha2beta1 integrins did not inhibit collagen I-induced osteogenesis by hMSCs. These data demonstrate that collagen I promotes proliferation and osteogenesis of hMSCs via activation of ERK and Akt pathways.

Apoptosis is an inevitable process during development and is evident in the formation of articular cartilage and endochondral ossification of growth plate. Mesenchymal stem cells (MSCs) can serve as alternative sources for cell therapy in focal chondral lesions or diffuse osteoarthritis. But there are few, if any, studies investigating apoptosis during chondrogenesis by MSCs. The aim of this study was to find the better condition to prevent apoptosis during chondrogenesis by MSCs. Apoptosis were evaluated in MSCs induced in different chondrogenic media by the use of Annexin V, TUNEL staining, lysosomal labeling with lysotracker and immunostaining of apoptotic markers. We found apparent apoptosis was demonstrated by Annexin V, TUNEL staining and lysosomal labeling during chondrogenesis. Meanwhile, the degree of apoptosis was related to the reagents of the defined chondrogenic medium. Adding serum in medium increased apoptosis, however, TGF-beta1 inhibited apoptosis. The apoptosis was associated with the activation of caspase-3, the increase in the Bax/Bcl-2 ratio, the loss of lysosomal integrity, and the increase of PARP-cleavage. Pro-inflammatory cytokines, IL-1alpha, IL-1beta and TNFalpha did not induce any increase in apoptosis. Interestingly, the inhibition of apoptosis by serum free medium supplemented with ITS was also associated with an increase in the expression of type II collagen, and a decrease in the expression of type X collagen, Runx2, and other osteogenic genes, while TGF-beta1 increased the expression of Sox9, type II and type X collagen and decreased the expression of osteogenic genes. These data suggest apoptosis occurs during chondrogenesis by MSCs by cell death intrinsic pathway activation and this process may be modulated by culture conditions.

The internal quantum efficiency (IQE) of commercial ultra high brightness AlGaInP red LED has already reached 90% or higher but the light extraction efficiency was only about 30% to 50%. Through the improvement of surface texturing structure by nano-imprint technology and current spreading by using narrow width ohmic contact metal line, the light extraction efficiency of AlGaInP red LED was significantly improved up to 60%. In AlGaInN LED, the thermal resistance of the LED chip can be reduced by thinning down or totally removing the sapphire substrate and then replacing it by high thermal conductivity materials. Therefore, the performances of high power AlGaInN LED chips were improved in high current density operation condition.