Highly ordered magnetic Ni nanotubules (see Figure) have been successfully prepared. Electrodeposition in the pores of an alumina membrane modified with an organoamine as pore‐wall modifying agent results in a perfectly ordered array of such metal nanotubules tens of micrometers long. These metal nanotubules with open ends could be employed for the creation of materials with special magnetic, optical, or electrical properties.
Purpose: Abnormal growth of vertebral body growth plate (VBGP) is considered as one of the etiologic factors in the adolescent idiopathic scoliosis (AIS). It was well-known that melatonin was correlated with the emergence and development of AIS. This study aimed to investigate the effect of melatonin on rat VBGP chondrocytes in vitro.Methods:Chondrocytes were isolated from rat VBGP, and treated with or without melatonin. Cell proliferation was measured by the Alamar Blue assay. Gene expression of collagen type II and aggrecan were evaluated by real-time PCR. Expression of the melatonin receptors (MT1, MT2), proliferating cell nuclear antigen (PCNA, a cell proliferation marker), Sox9 (a chondrocytic differentiation marker) and Smad4 (a common mediator in regulating the proliferation and differentiation of chondrocytes) were detected by Western blotting.Results: Expression of melatonin receptors (MT1, MT2) were detected in the rat VBGP chondrocytes. Melatonin, at 10 and 100 µg/mL concentration, significantly inhibited the proliferation of VBGP-chondrocytes and the gene expression of collagen type II and aggrecan, and down-regulated the protein expression of PCNA, Sox9 and Smad4. In addition, the inhibitory effect of melatonin was reversed by luzindole, a melatonin receptor antagonist.Conclusions: These results suggest that melatonin at high concentrations can inhibit the proliferation and differentiation of VBGP chondrocytes, which might give some new insight into the pathogenic mechanism of AIS.
Ossification of ligamentum flavum (OLF) is a pathological ectopic ossification in the spinal ligament, leading to spinal canal stenosis, but little was known about its pathogenesis. A previous study has found growth/differentiation factor (GDF)-5 expression at ossified sites of the ligaments from OLF patients. This study aimed to investigate the osteogenic effects of GDF-5 on cultured human ligamentum flavum cells (LFCs). LFCs were isolated from human spinal ligamentum flavum, and treated with or without recombinant human (rh) GDF-5. Alkaline phosphatase (ALP) activity was measured. Expression of osteocalcin was assessed by reverse transcriptase-PCR, Western blotting and immunofluorescence. Matrix mineralization was assessed by alizarin red staining. Activation of mitogen-activated protein kinases (MAPK) ERK1/2, p38 and JNK were detected by Western blotting. We found that rhGDF-5 treatment increased ALP activity and osteocalcin expression in a time-and dosedependent manner, and induced mineralized nodule form. In addition, rhGDF-5 challenge mediated the ERK1/2 and p38 activation but not JNK. Inhibiting this activation pharmacologically, using U0126, a ERK1/ 2 inhibitor, or SB203580, a p38 inhibitor, resulted in significantly lower ALP activity and osteocalcin protein expression. The present study shows that rhGDF-5 induces osteogenic differentiation of human LFCs through activation of ERK1/2 and p38 MAPK. These findings give some new insight into the pathogenesis of OLF.
To more comprehensively and accurately address model uncertainties in the East Asia monsoon region, a single-physics suite, where each ensemble member uses the same set of physics parameterizations as the control member in combination with multiple stochastic schemes, is developed to investigate if the multistochastic schemes that combine different stochastic schemes together can be an alternative to a multiphysics suite, where each ensemble member uses a different set of physics parameterizations (e.g., cumulus convection, boundary layer, surface layer, microphysics, and shortwave and longwave radiation). For this purpose, two experiments are performed for a summer monsoon month over China: one with a multiphysics suite and the other with a single-physics suite combined with multistochastic schemes. Three stochastic schemes are applied: the stochastically perturbed parameterizations (SPP) scheme, consisting of temporally and spatially varying perturbations of 18 parameters in the microphysics, convection, boundary layer, and surface layer parameterization schemes; the stochastically perturbed parameterization tendencies (SPPT) scheme; and the stochastic kinetic energy backscatter (SKEB) scheme. The combination of the three stochastic schemes is compared with the multiphysics suite in the Global and Regional Assimilation and Prediction Enhanced System–Regional Ensemble Prediction System with a horizontal grid spacing of 15 km. Verification results show that, overall, a single-physics suite that combines SPP, SPPT, and SKEB outperforms the multiphysics suite in precipitation verification and verification for upper-air weather variables, 10-m zonal wind, and 2-m temperature in the East Asian monsoon region. The indication is that a single-physics suite combining SPP, SPPT, and SKEB may be an appropriate alternative to a multiphysics suite. This finding lays a foundation for the development and design of future regional and global ensembles.
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