The HKUST-1@SBA-15 composites with hierarchical pore structure were constructed by in situ self-assembly of metal-organic framework (MOF) with mesoporous silica. The structure directing role of SBA-15 had an obvious impact on the growth of MOF crystals, which in turn affected the morphologies and structural properties of the composites. The pristine HKUST-1 and the composites with different content of SBA-15 were characterized by XRD, N adsorption-desorption, SEM, TEM, FT-IR, TG, XPS, and CO-TPD techniques. It was found that the composites were assembled by oriented growth of MOF nanocrystals on the surfaces of SBA-15 matrix. The interactions between surface silanol groups and metal centers induced structural changes and resulted in the increases in surface areas as well as micropore volumes of hybrid materials. Besides, the additional constraints from SBA-15 also restrained the expansion of HKUST-1, contributing to their smaller crystal sizes in the composites. The adsorption isotherms of CO on the materials were measured and applied to calculate the isosteric heats of adsorption. The HS-1 composite exhibited an increase of 15.9% in CO uptake capacity compared with that of HKUST-1. Moreover, its higher isosteric heats of CO adsorption indicated the stronger interactions between the surfaces and CO molecules. The adsorption rate of the composite was also improved due to the introduction of mesopores. Ten cycles of CO adsorption-desorption experiments implied that the HS-1 had excellent reversibility of CO adsorption. This study was intended to provide the possibility of assembling new composites with tailored properties based on MOF and mesoporous silica to satisfy the requirements of various applications.

Defecation allows the body to eliminate waste, an essential step in food processing for animal survival. In contrast to the extensive studies of feeding, its obligate counterpart, defecation, has received much less attention until recently. In this study, we report our characterizations of the defecation behavior of Drosophila larvae and its neural basis. Drosophila larvae display defecation cycles of stereotypic frequency, involving sequential contraction of hindgut and anal sphincter. The defecation behavior requires two groups of motor neurons that innervate hindgut and anal sphincter, respectively, and can excite gut muscles directly. These two groups of motor neurons fire sequentially with the same periodicity as the defecation behavior, as revealed by in vivo Ca2+ imaging. Moreover, we identified a single mechanosensitive sensory neuron that innervates the anal slit and senses the opening of the intestine terminus. This anus sensory neuron relies on the TRP channel NOMPC but not on INACTIVE, NANCHUNG, or PIEZO for mechanotransduction.DOI: http://dx.doi.org/10.7554/eLife.03293.001

Imbalanced metabolism of Nucleus pulposus (NP) extracellular matrix (ECM) is closely correlated to Intervertebral Disc Degenerative Disease. LIM mineralization protein-1 (LMP-1) has been proven to induce sulfated glycosaminoglycan (sGAG) production in NP and have an anti-inflammatory effect in pre-osteoclast. However, whether it has any effect on the NP ECM production and degradation under inflammatory stimulation has not been studied. In the current study, a TNF-a induced cell model was established in vitro. Lentivirus encoding LMP-1 (LV-LMP-1) and short heparin LMP-1 (LV-shLMP-1) were constructed to overexpress and knockdown LMP-1 expression in NP cells. LMP-1 mRNA level was regulated in a dose-dependent manner after transfection. LV-LMP-1 increased whereas LV-shLMP-1 decreased collagen II, aggrecan, versican expression, and sGAG production. LV-LMP-1 abolished while LVshLMP-1 aggravated TNF-a mediated down-regulation of the above matrix genes via ERK1/2 activation. Moreover, LV-LMP-1 abrogated TNF-a induced MMP-3 and MMP-13 expression via inhibiting p65 translocation and MMP-3 and MMP-13 promoter activity. These results indicated that LMP-1 had an ECM production maintenance effect under inflammatory stimulation. This effect was via up-regulation of matrix genes expression at least partially through ERK1/2 activation, and down-regulation of MMPs expression through NF-kB inhibition. Keywords: LIM Mineralization Protein-1; intervertebral disc degeneration; matrix metalloproteinase; extracellular matrix; NF-kB Intervertebral disc degeneration (IVDD) is a common degenerative process of the spine as aged. 1 It has been acknowledged that IVDD is one of the most important factors associated with spinal degenerative diseases including disc herniation, spinal canal stenosis, spondylolysthesis, and degenerative scoliosis. 1,2 These diseases cause back pain, radiculopathy or myelopathy, leading to disability, low health related quality of life (HRQOL), and economic losses. Conservative treatment and surgical treatments of spinal degenerative diseases in the late stage is at huge cost and result in suboptimal clinical outcomes in many situation. 1,2 Thus, early intervention to prevent the progression of IVDD, or regenerate the degenerative disc is of great necessity.Nucleus pulposus (NP) extracellular matrix (ECM) consists mainly of loosely assembled collagen type II fibers and proteoglycan (mostly aggrecan and versican), which enable the nucleus pulposus to retain water, thereby cushioning and absorbing the considerable loads placed on the tissue. 3 IVDD is believed to be, in part, the result of imbalance between anabolism and catabolism of ECM. 4 MMPs play a central role in the disc degeneration mainly by cleaving collagens and aggrecan in NP ECM, resulting in the loss of normal disc function. 5-10 Inflammatory cytokines, which are proven to highly express in degenerative IVD, can increase MMPs expression and related ECM degradation. 11,12 As pathophysiological mechanism of IVDD has been better delineated, grow...

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