462 research outputs found
Traditional Chinese Medicine Therapy for Targeting Osteoblastogenesis
Osteoblasts are derived from bone marrow mesenchymal stem cell (BMSC) precursors, which differentiate into mature osteoblasts and mediate bone formation. This process is called osteoblastogenesis. A deficiency in osteoblastogenesis of BMSCs can result in bone-related diseases including osteoporosis. Thus, developing drugs for targeting osteoblastogenesis from BMSCs has become one of the therapeutic strategies for osteoporosis. In China, kidney-nourishing Chinese herbal drugs such as ER-Zhi-Wan have been believed to be potential for treating osteoporosis through targeting osteoblast proliferation and differentiation. The key pathways for regulating osteoblastogenesis include canonical and noncanonical Wnt pathway, semaphorin-mediated pathway, and MAPK-mediated BMP2-Smad pathway. Some natural products have been confirmed to regulate more than one pathway and exert multi-target effect through the use of one compound or combined use of more than two compounds, such as wedelolactone and oleonuezhenide. In addition, tissue engineering provides a promising strategy in the field for targeting osteoblastogenesis. New types of biomaterials including hydroxyapatite (HAp) combined with Chinese medicine can exert enhanced effect on osteoblastogenesis and provide new therapy for treating osteoporosis
A Weak Galerkin Mixed Finite Element Method for second order elliptic equations on 2D Curved Domains
This article concerns the weak Galerkin mixed finite element method (WG-MFEM)
for second order elliptic equations on 2D domains with curved boundary. The
Neumann boundary condition is considered since it becomes the essential
boundary condition in this case. It is well-known that the discrepancy between
the curved physical domain and the polygonal approximation domain leads to a
loss of accuracy for discretization with polynomial order . The
purpose of this paper is two-fold. First, we present a detailed error analysis
of the original WG-MFEM for solving problems on curved domains, which exhibits
an convergence for all . It is a little surprising to
see that even the lowest-order WG-MFEM () experiences a loss of
accuracy. This is different from known results for the finite element method
(FEM) or the mixed FEM, and appears to be a combined effect of the WG-MFEM
design and the fact that the outward normal vector on the polygonal
approximation domain is different from the one on the curved domain. Second, we
propose a remedy to bring the approximation rate back to optimal by employing
two techniques. One is a specially designed boundary correction technique. The
other is to take full advantage of the nice feature that weak Galerkin
discretization can be defined on polygonal meshes, which allows the curved
boundary to be better approximated by multiple short edges without increasing
the total number of mesh elements. Rigorous analysis shows that a combination
of the above two techniques renders optimal convergence for all .
Numerical results further confirm this conclusion
Superconductivity in epitaxially grown LaVO3/KTaO3(111) heterostructures
Complex oxide heterointerfaces can host a rich of emergent phenomena, and
epitaxial growth is usually at the heart of forming these interfaces. Recently,
a strong crystalline-orientation-dependent two-dimensional superconductivity
was discovered at interfaces between KTaO3 single-crystal substrates and films
of other oxides. Unexpectedly, rare of these oxide films was epitaxially grown.
Here, we report the existence of superconductivity in epitaxially grown
LaVO3/KTaO3(111) heterostructures, with a superconducting transition
temperature of ~0.5 K. Meanwhile, no superconductivity was detected in the
(001)- and (110)-orientated LaVO3/KTaO3 heterostructures down to 50 mK.
Moreover, we find that for the LaVO3/KTaO3(111) interfaces to be conducting, an
oxygen-deficient growth environment and a minimum LaVO3 thickness of ~0.8 nm (~
2 unit cells) are needed.Comment: 5 figures, plus 6 supplementary figure
Prostate cancer ā a biomarker perspective
Despite early detection and reduced risk of death, prostate cancer still remains the second leading cause of cancer death in American men. There is currently no cure for advanced prostate cancer. The multistage, stochastic and highly heterogeneous nature of prostate cancer, coupled with genetic and epigenetic alterations that occur during disease progression and response to therapy, represent fundamental challenges in our quest to understand and control this complex and prevalent disease. Recent advances in drug development and breakthroughs in omics technologies have renewed our efforts to identify novel biomarkers for prostate cancer prognosis, prediction, and therapeutic response monitoring. In this perspective article, we overview the current status and highlight future prospects of biomarkers for prostate cancer, a disease that affects millions of men worldwide
Synthesis, Characterization, and Tribological Behavior of Oleic Acid Capped Graphene Oxide
Graphene oxide (GO) nanosheets were prepared by modified Hummers and Offeman methods. Furthermore, oleic acid (OA) capped graphene oxide (OACGO) nanosheets were prepared and characterized by means of Fourier transform-infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), and X-ray diffraction (XRD). At the same time, the friction and wear properties of OA capped graphite powder (OACG), OACGO, and oleic acid capped precipitate of graphite (OACPG) as additives in poly-alpha-olefin (PAO) were compared using four-ball tester and SRV-1 reciprocating ball-on-disc friction and wear tester. By the addition of OACGO to PAO, the antiwear ability was improved and the friction coefficient was decreased. Also, the tribological mechanism of the GO was investigated
Mitochondrial-targeting Lonidamine-Doxorubicin nanoparticles for synergistic chemotherapy to conquer drug resistance
Lonidamine
(LND) can act on mitochondria and inhibit energy metabolism in cancer
cells and therefore has been used together with chemotherapy drugs
for synergistically enhanced therapeutic efficacy. However, its use
is hindered by the poor solubility and slow diffusion in the cytoplasm.
To address these problems, we designed and prepared aqueous dispersible
nanoparticles (NPs) containing integrated components including triphenylphosphine
(TPP) to target the mitochondria of cells and LND and doxorubicin
(DOX) for synergistic cancer treatment and conquering drug resistance.
This design allows the NPs to concentrate in the mitochondria of cells,
solve the low solubility of LND, and contain very high load of LND
and DOX in comparison with previously reported drug-delivery systems
based on various carrier nanomaterials. Detailed mechanism studies
reveal that TPP-LND-DOX NPs could induce significant reactive oxygen
species production, mitochondrial membrane potential decrease, and
mitochondrial apoptosis pathway, thereby leading to great cytotoxicity
in cancer cells. In vivo anticancer activities indicate that TPP-LND-DOX
NPs exhibit the highest efficacy in tumor inhibition among all tested
groups and show high effectiveness in drug-resistant model. This work
demonstrates the potential use of our TPP-LND-DOX NPs to jointly promote
the mitochondria apoptosis pathway and contribute to conquer drug
resistance in cancer therapy
Designing 3D graphene networks via a 3D-printed Ni template
Copyright Ā© Royal Society of Chemistry 2015It is highly desirable to design and control the properties of 3D graphene networks with preferred shapes, lengths, diameters of the trusses so as to add new functionalities. Hereby, we demonstrate a conceptual design and the practical synthesis of periodic 3D graphene networks via CVD using a 3D-printed Ni scaffold as the template.Natural Science foundation of Heilongjiang province of ChinaEU/FP
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