Topology Control of Covalent Organic Frameworks with Interlaced Unsaturated 2D and Saturated 3D Units for Boosting Electrocatalytic Hydrogen Peroxide Production.

Modulating the electronic state of multicomponent covalent organic framework (COF) electrocatalysts is crucial for enhancing catalytic activity. However, the effect of dimensionality on their physicochemical functionalities is still lacking. Herein, we report an interlaced unsaturated 2D and saturated 3D strategy to develop multicomponent-regulated COFs with tunable gradient dimensionality for high selectivity and activity electrocatalysis. Compared with the two-component 2D and 3D model COFs, the 2D/3D framework interlaced COFs with locally irregular dimensions and electronic structures are more practical in optimizing the intrinsic electrode surface reaction and mass transfer. Remarkably, the unsaturated 2D-inserted 3D TAE-COF regulates the adsorption mode of OOH* species to supply a favorable dynamic pathway for the H2O2 process, thereby achieving an excellent production rate of 8.50 mol gcat-1 h-1. Moreover, utilizing theoretical calculation and in situ ATR-FTIR experiment, we found that the central carbon atom of the tetraphenyl-based unit (site-1 and site-6) are potential active sites. This strategy of operating the adsorption ability of reactants with dimensionality-interconnected building blocks provides an idea for designing durable and efficient electrocatalysts.

Positional Thiophene Isomerization: A Geometric Strategy for Precisely Regulating the Electronic State of Covalent Organic Frameworks to Boost Oxygen Reduction.

With the oxygen conversion efficiency of metal-free carbon-based fuel cells dramatically improved, the building blocks of covalent organic frameworks (COFs) raised principal concerns on the catalytic active sites with indistinct electronic states. Herein, to address this issue, we demonstrate COFs for oxygen reduction reaction (ORR) by regulating the edge-hanging thiophene units, and the molecular geometries are further modulated via positional thiophene isomerization strategy, affording isomeric COF-α with 2-substitution and COF-ß with 3-substitution on the frameworks. The electronic states and intermediate adsorption ability are well-regulated through geometric modification, resulting in controllable chemical activity and local density of π-electrons. Notably, the introduction of thiophene units with different substitution positions into a pristine pure carbon-based COF model COF-Ph achieves excellent activity with a half-wave potential of 0.76 V versus the reversible hydrogen electrode, which is higher than most of those metal-free or metal-based electrocatalysts. Utilizing the combination of theoretical prediction and in situ Raman spectra, we show that the isomeric thiophene skeleton (COF-α and COF-ß) can induce the dangling unit activation, accurately identifying the pentacyclic-carbon (thiophene α-position) adjacent to sulfur atom as active sites. The results suggest that the isomeric dangling groups in COFs are suitable for the ORR with promising geometry construction.

Papaver somniferum and Papaver rhoeas Classification Based on Visible Capsule Images Using a Modified MobileNetV3-Small Network with Transfer Learning.

Traditional identification methods for Papaver somniferum and Papaver rhoeas (PSPR) consume much time and labor, require strict experimental conditions, and usually cause damage to the plant. This work presents a novel method for fast, accurate, and nondestructive identification of PSPR. First, to fill the gap in the PSPR dataset, we construct a PSPR visible capsule image dataset. Second, we propose a modified MobileNetV3-Small network with transfer learning, and we solve the problem of low classification accuracy and slow model convergence due to the small number of PSPR capsule image samples. Experimental results demonstrate that the modified MobileNetV3-Small is effective for fast, accurate, and nondestructive PSPR classification.

Self-emulsifying drug delivery system improves preventive effect of curcuminoids on chronic heart failure in rats.

Several studies have reported the preventive or therapeutic effect of curcuminoids on chronic heart failure (CHF), but their application was limited due to low solubility and bioavailability. Our previous study indicates that self-emulsifying drug delivery system (SEDDS) improves the solubility and bioavailability of curcuminoids. Thus, the aim of this work was to investigate whether SEDDS could improve preventive effect of curcuminoids on CHF in rats. CHF model was were established by coronary artery ligation. Ninety rats were randomly and averagely divided into sham, model, low- or high-dose suspension or SEDDS of curcuminoids (66.68 or 266.68 mg/kg) groups. Hemodynamic indices were recorded by multipurpose polygraph. Serum oxidative indices, B-type natriuretic peptide (BNP) and heart weight index were determined by kits and electronic balance. Myocardial infarct area, ventricular dilatation degree and collagen volume fraction of myocardial interstitium were analyzed by Masson staining, picric acid and sirius red staining, light microscopy and image analysis system. Myocardial histopathology was observed by hematoxylin and eosin staining, Masson staining and light microscopy. Reduction of ventricular pump function, increase of BNP level and heart weight index, myocardial lipid peroxidation damage, myocardial infarction, myocardial fibrosis, and cardiac enlargement were detected or observed in model group relative to those in sham group. After treatment with suspension or SEDDS of curcuminoids, the above-mentioned pathological changes were obviously reversed relative to those in model group. Meanwhile, the ameliorative effect of SEDDS of curcuminoids was markedly better than that of suspension of curcuminoids. This work provides a valuable reference from pharmacodynamics for development of curcuminoids pharmaceutics.

Occupational exposure to methylene chloride and risk of cancer: a meta-analysis.

METHODS: We searched MEDLINE and EMBASE for epidemiologic studies on occupational exposure to methylene chloride and risk of cancer. Estimates of study-specific odds ratios (ORs) were calculated using inverse-variance-weighted fixed-effects models and random-effects models. Statistical tests for heterogeneity were applied. RESULTS: We summarized data from five cohort studies and 13 case-control studies. The pooled OR for multiple myeloma was (OR 2.04; 95 % CI 1.31-3.17) in relation to occupational exposure to methylene chloride but not for non-Hodgkin's lymphoma, leukemia, breast, bronchus, trachea and lung, brain and other CNS, biliary passages and liver, prostate, pancreas, and rectum. Furthermore, we focused on specific outcomes for non-Hodgkin's lymphoma and multiple myeloma because of exposure misclassification. The pooling OR for non-Hodgkin's lymphoma and multiple myeloma was 1.42 (95 % CI 1.10-1.83) with moderate degree of heterogeneity among the studies (I (2) = 26.9 %, p = 0.205). CONCLUSIONS: We found an excess risk of multiple myeloma. The non-Hodgkin's lymphoma and leukemia that have shown weak effects should be investigated further.

Bis[4-chloro-2-(quinolin-8-yl-imino-meth-yl)phenolato-κ(3) N,N',O]cobalt(III) trichlorido-methano-lcobaltate(II).

The reaction of 4-chloro-2-(quinolin-8-yl-imino-meth-yl)phenol (HClQP) with cobalt(II) dichloride hexa-hydrate in methanol/chloro-form under solvothermal conditions yielded the title compound, [Co(C16H10ClN2O)2][CoCl3(CH3OH)]. The Co(III) atom is six-coordinated in a slightly distorted octa-hedral geometry by four N atoms and two O atoms of two tridentate HClQP ligands, which are nearly perpendicular to each other, making a dihedral angle of 86.95°. The Co(II) atom is four-coordinated by three Cl atoms and one O atom from a methanol ligand in a distorted tetra-hedral geometry. The crystal packing is consolidated by inter-molecular O-H⋯Cl, C-H⋯Cl and C-H⋯O hydrogen bonds, forming a three-dimensional supra-molecular structure, in which [Co(II)Cl3(CH3OH)] anions are connected via O-H⋯Cl and C-H⋯Cl hydrogen bonds into centrosymmetric dimers. Neighboring cobalt(III) complexes form dimers through C-H⋯O hydrogen bonds, as well as π-π stacking [centroid-centroid distances = 3.30 (2) Å] between the planar quinoline systems of one HClQP ligand and the phenolate ring of another.

Interleukin-35 dampens T helper 22 phenotype shift in CD4+CD25+CD127dim/- regulatory T cells in primary biliary cholangitis.

The phenotype shift in regulatory T cells (Tregs) contributes to immunopathogenesis of autoimmune diseases. The current study was aimed to investigate the regulatory function of interleukin-35 (IL-35) to T helper 22 (Th22) cell phenotype shift in Tregs in primary biliary cholangitis (PBC). Fifty-five PBC patients and twenty-four controls were enrolled. CD4+CD25+CD127dim/- Tregs and Th22 cells were investigated by flow cytometry. Forkhead box P3 (FoxP3) and aryl hydrocarbon receptor (AhR) mRNA levels were assessed by real-time polymerase chain reaction. Plasma IL-10 and IL-22 levels were measured by ELISA. Purified Tregs were stimulated with exogenous IL-35, and were co-cultured with autologous CD4+CD25- T cells. Cellular proliferation and cytokine production was measured. Purified Tregs were also cultured into Th22 condition in the presence or absence of exogenous IL-35, and Th22 phenotype were assessed. PBC patients had lower levels of Treg percentage, FoxP3 mRNA, and plasma IL-10, while had higher levels of Th22 proportion, AhR mRNA, and plasma IL-22. Tregs from PBC patients showed reduced immunosuppressive activity, which presented as increased cellular proliferation, interferon-γ production and decreased IL-35/IL-10 secretion in co-culture system. Tregs shifted into Th22 phenotype in PBC patients with elevated CCR4, CCR6, and CCR10 expression as well as increased IL-22 production. IL-35 not only enhanced inhibitory function of Tregs but also suppressed phenotype shift of Tregs into Th22 phenotype in PBC patients. This process was accompanied by elevation of IL-10 and transforming growth factor-ß1 secretion by Tregs from PBC patients. The present data suggested that reduced IL-35 might be insufficient to maintain Tregs function and phenotype shift from Tregs into Th22 phenotype in PBC patients.

Metal-Free Carbon-Based Covalent Organic Frameworks with Heteroatom-Free Units Boost Efficient Oxygen Reduction.

Accurate identification of carbon-based metal-free electrocatalyst (CMFE) activity and enhancing their catalytic efficiency for O2 conversion is an urgent and challenging task. This study reports a promising strategy to simultaneously develop a series of covalent organic frameworks (COFs) with well-defined heterocyclic-free biphenyl or fluorenyl units. Unlike heteroatom doping, the developed method not only supplies methyl-induced molecular configuration to promote activity, but also provides a direct opportunity to identify heteroatom-free carbon active centers. The introduction of methyl groups (MGs) with reversible valence bonds into a pristine biphenyl-based COF results in an excellent performance with a half-wave potential of 0.74 V versus the reversible hydrogen electrode (RHE), which is among the highest values for CMFE-COFs as oxygen reduction reaction (ORR) electrocatalysts. Combined with in situ Raman spectra and theoretical calculations, the MG-bound skeleton (DAF-COF) is found to produce ortho activation, confirming the ortho carbon (site-5) adjacent to MGs as active centers. This may be attributed to the opening and binding of MGs, which effectively regulate the molecular configuration and charge redistribution, as well as improve charge transfer and reduce the energy barrier. This study provides insight into the design of highly efficient metal-free organic electrocatalysts via the regulation of valence bonds.

Tensile-Strained Holey Pd Metallene toward Efficient and Stable Electrocatalysis.

Noble metal-based metallenes are attracting intensive attention in energy catalysis, but it is still very challenging to precisely control the surface structures of metallenes for higher catalytic properties on account of their intrinsic thermodynamic instability. Herein, the synthesis of tensile-strained holey Pd metallene by oxidative etching is reported using hydrogen peroxide, which exhibits highly enhanced catalytic activity and stability in comparison with normal Pd metallene toward both oxygen reduction reaction and formic acid oxidation. The pre-prepared Pd metallene functions as a catalyst to decompose hydrogen peroxide, and the Pd atoms in amorphous regions of Pd metallene are preferentially removed by the introduced hydrogen peroxide during the etching process. The greatly enhanced ORR activity is mainly determined by the strong electrostatic repulsion between intermediate O* and the dopant O, which balances the adsorption strength of O* on Pd sites, ultimately endowing a weakened adsorption energy of O* on TH-Pd metallene. This work creates a facile and economical strategy to precisely shape metallene-based nanoarchitectures with broad applications for energy systems and sensing devices.

Dynamic compression of rabbit adipose-derived stem cells transfected with insulin-like growth factor 1 in chitosan/gelatin scaffolds induces chondrogenesis and matrix biosynthesis.

Articular cartilage is routinely subjected to mechanical forces and growth factors. Adipose-derived stem cells (ASCs) are multi-potent adult stem cells and capable of chondrogenesis. In the present study, we investigated the comparative and interactive effects of dynamic compression and insulin-like growth factor-I (IGF-I) on the chondrogenesis of rabbit ASCs in chitosan/gelatin scaffolds. Rabbit ASCs with or without a plasmid overexpressing of human IGF-1 were cultured in chitosan/gelatin scaffolds for 2 days, then subjected to cyclic compression with 5% strain and 1 Hz for 4 h per day for seven consecutive days. Dynamic compression induced chondrogenesis of rabbit ASCs by activating calcium signaling pathways and up-regulating the expression of Sox-9. Dynamic compression plus IGF-1 overexpression up-regulated expression of chondrocyte-specific extracellular matrix genes including type II collagen, Sox-9, and aggrecan with no effect on type X collagen expression. Furthermore, dynamic compression and IGF-1 expression promoted cellular proliferation and the deposition of proteoglycan and collagen. Intracellular calcium ion concentration and peak currents of Ca(2+) ion channels were consistent with chondrocytes. The tissue-engineered cartilage from this process had excellent mechanical properties. When applied together, the effects achieved by the two stimuli (dynamic compression and IGF-1) were greater than those achieved by either stimulus alone. Our results suggest that dynamic compression combined with IGF-1 overexpression might benefit articular cartilage tissue engineering in cartilage regeneration.

Transplantation of Cbfa1-overexpressing adipose stem cells together with vascularized periosteal flaps repair segmental bone defects.

BACKGROUND: Segmental bone defect is still a challenge to orthopedic surgeons. Currently available therapies for segmental bone defects have some drawbacks. Tissue engineering using pluripotent stem cells is a new, promising method for bone repair. The present study aims to promote the effect of bone defect repair using the tissue engineered bone in combination with vascularized periosteal flaps. METHODS: The adenoviral vector carrying Cbfa1 transduced rabbit adipose-derived mesenchymal stem cells and gene modified tissue engineering bone (GMB) were constructed. Rabbits with radial defects were implanted with the GMB together with vascularized periosteum (group A); or GMB with free periosteum (group B); or GMB (group C), and scaffold (group D). The bone repair effect was evaluated at 4, 8, or 12 wk, respectively, after the operations. RESULTS: Cbfa1 proteins were strongly expressed in adipose stem cells (ADSCs) that formed a stratified network on the inner surface of the polylactic acid/ polycaprolacton (PLA/PCL) pores. Bone repair was well achieved in the rabbits treated with the Cbfa1-expressing ADSCs and vascularized flap that was markedly better than those treated with either Cbfa1-expressing ADSCs alone or with vascularized flap alone. CONCLUSIONS: Combination with implanting the Cbfa1 gene-modified tissue-engineered bone and vascularized periosteum can better repair the segmental bone defects by stimulating osteogenesis, osteoinduction, and osteoconduction than using either one of the approaches.

Ru-incorporated Co3O4 nanoparticles from self-sacrificial ZIF-67 template as efficient bifunctional electrocatalysts for rechargeable metal-air battery.

Ru-incorporated Co3O4 nanoparticles have been synthesized from self-sacrificial ZIF-67 template and utilized as efficient electrocatalysts towards oxygen reduction and evolution reactions (ORR and OER). Amongst, Ru@Co3O4-1.0 exhibited the optimum electrocatalytic behavior with an ultra-low potential gap (0.84 V) between the OER potential (1.61 V at 10 mA cm-2) and ORR half-wave potential (0.77 V). The zinc-air battery using Ru@Co3O4-1.0 as a cathode presented high specific capacity (788.1 mAh g-1) and power density (101.2 mW cm-2). Meanwhile, this battery possessed relatively lower voltage gap and higher cycling stability compared with the commercial Pt/C-based one. Ruthenium incorporation induced remarkable lattice expansion of Co3O4 and engineered more oxygen vacancies, promoting the lattice oxygen mobility from the subsurface/bulk phase onto surface. All these properties were recognized to be the crucial parameters for electrocatalytic activity improvement. This work provided a facile approach to design highly active metal oxide with broad potentiality for rechargeable metal-air batteries.

OsGF14b is involved in regulating coarse root and fine root biomass partitioning in response to elevated [CO2] in rice.

Elevated [CO2] can increase rice biomass and yield, but the degree of this increase varies substantially among cultivars. Little is known about the gene loci involved in the acclimation and adaptation to elevated [CO2] in rice. Here, we report on a T-DNA insertion mutant in japonica rice exhibiting a significantly enhanced response to elevated [CO2] compared with the wild type (WT). The root biomass response of the mutant was higher than that of the WT, and this manifested in the number of adventitious roots, the average diameter of roots, and total root length. Furthermore, coarse roots (>0.6 mm) and thin lateral roots (<0.2 mm) were more responsive to elevated [CO2] in the mutant. When exposed to lower light intensity, however, the response of the mutant to elevated [CO2] was not superior to that of the WT, indicating that the high response of the mutant under elevated [CO2] was dependent on light intensity. The T-DNA insertion site was located in the promoter region of the OsGF14b gene, and insertion resulted in a significant decrease in OsGF14b expression. Our results indicate that knockout of OsGF14b may improve the response to elevated [CO2] in rice by enhancing carbon allocation to coarse roots and to fine lateral roots.

[Significance of double-oblique multiplanar reconstruction of the treatment decision-making in sacral fracture with sacral neurological damage].

OBJECTIVE: To study diagnostic and surgical significance of the multiplanar reconstruction (MPR) of spiral CT in sacral fracture with sacral neurological damage. METHODS: From April 2007 to April 2009, 10 cases of sacral fracture with sacral neurological damage in Shengjing Hospital of China Medical University were examined by double-oblique MPR of sacrum to show a total length of the sacral neural tube, and observe the course of sacral neural tube and the relationship between fracture and the neural tube. There were 7 males and 3 females, aged 30 - 55 years. The time from injury to hospitalization varied from 1 day to 1 months. The injury was caused by traffic accident in 6 cases, smash of heavy object in 3 cases and crush in 1 cases. All patients were examined with double-oblique MPR (coronal oblique 45 degrees and 30 degrees oblique-shaped bit lost)to display the course of sacral neural tube and the condition of clearly, which was confirmed by operation and clinical validation. RESULTS: The clinical manifestations and international standards for Neurological Classification of Spinal Cord Injury recommended by American Spinal Injury Association International Spinal Cord Society were the basis for clinical diagnose. Nerve injury diagnosed by clinical manifestation were S1 (6 cases), S2 (2 cases), S1 and S2 (2 cases). After double-oblique MPR in patients, we found 3 patients have fractures in sacral neural tube of S1, 1 patients in S2, and 2 patients both in S1 and S2, whom recovered average 12 month after operation (S1 and S2 nerve were pressed by fractures according to operating observation); And there were no fractures in sacral neural tube of other patients (3 cases in S1, 1 cases in S2), these were contund, whom were recovered average 13 month after expectant treatment. CONCLUSIONS: Double-oblique MPR of sacrum has important clinical significance in diagnosis of nature and location with sacral nerve injury, as well as surgical planning. It can be used as routine examination of patients with sacral fracture.

[Situation of pesticide poisoning in Huzhou from 2006 to 2009].

OBJECTIVE: To understand the situations of pesticide poisoning in Huzhou and take preventive strategy and measures against the pesticide poisoning. METHODS: Case reports between 2006 and 2009 in the data base of reporting system for occupational diseases were computed by Excel for windows and statistical significance by SPSS12.0. RESULTS: A total of 2298 patients were reported from 2006 to 2009. Among them, the incidence of occupational poisoning accounted for 25.59% (588 cases), including 4 fatalities (fatality rate, 0.68%). Male patients (458 cases, 77.89%) were more than female ones (130 cases, 22.11%) in occupational pesticides poisoning. Summer and autumn were the most seasons in occupational pesticides poisoning occurring. The incidence of non-occupational pesticides poisoning accounted for 74.41% (1710, cases), including 112 fatalities (fatality rate, 6.55%). Female patients (952 cases, 55.67%) were more than male ones (758 cases, 44.33%) in non-occupational pesticides poisoning. 15 - 55 years were the highest incidences among non-occupational pesticides poisoning patients. Insecticides especially organophosphorus insecticides such as methamidophos, parathion, and omethoate comprised a higher proportion, accounting for 79.98% of the pesticides poisoning. CONCLUSION: The incidence and the fatality rate of occupational pesticide poisoning were reduced in the city. However, more attention should be paid to non-occupational pesticides poisoning. To decrease the numbers of pesticide poisoning and the risks of death, the relevant departments should take preventive strategy and measures against the pesticide poisoning.

Polyhedral cobalt oxide supported Pt nanoparticles with enhanced performance for toluene catalytic oxidation.

Polyhedral CoOx was synthesized by calcination of Co-based metal-organic framework ZIF-67 and highly dispersed Pt nanoparticles were successfully loaded on CoOx. The catalytic results showed that Ptnano/CoOx had the best activity and stability. As compared with conventional Co3O4, polyhedral CoOx showed more excellent catalytic oxidation performance of toluene, which was related to enhanced oxygen mobility, defective structure and rich active oxygen species provided by Polyhedral CoOx. Moreover, Pt-CoOx metal-support interaction enhanced the dispersion of Pt species and showed more Pt0 ratio. It was reasonable that the gaseous O2 can be activated directly or moved into the catalyst's surface to form oxygen cycle.

Annexin A2 degradation contributes to dopaminergic cell apoptosis via regulating p53 in neurodegenerative conditions.

BACKGROUND: P53 overexpression has been shown to involve in mitochondria-mediated dapaminergic neuron cell death in Parkinson's disease. However, the exactly molecular mechanisms responsible for the p53-dependent intrinsic cell death in neurodegenerative conditions remain unclearly. Annexin A2 is a multifunctional protein that negatively regulates p53 expression. The purpose of this study was to explore the mechanism of p53 dependent dopaminergic cell death and implication of Annexin A2 in cellular apoptosis in 1-methyl-4-phenylpyridinium (MPP+)-induced PC12 cells. METHODS: The cell viability of neural PC12 cells was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltet-razolium bromide assay. Flow cytometry was used to evaluate the apoptosis and mitochondrial transmembrane potential of neural PC12 cells. The expression of p53 and Annexin A2 was analyzed by western blot assay. RESULTS: The present study showed that the exposure of PC12 cells to neurotoxin MPP+ increased the expression levels of p53 and the discharge of mitochondrial transmembrane potential. Notably, Annexin A2 degradation was also observed in this cellular model of Parkinson's disease, in a time and dose-dependent manner. This expressing change of Annexin A2 was in direct proportion to the loss of cell viability of PC12 cells, and this expression pattern was in inverse proportion to p53 levels in this cellular model of Parkinson's disease. CONCLUSION: These results indicated that Annexin A2 degradation plays a crucial role the degeneration of dapaminergic cells of Parkinson's disease, and Annexin A2 downregulation-mediated the cell death is closely associated with mitochondrial dysfunction via p53-dependent pathway; thus provide a novel therapeutic target for Parkinson's disease treatment.

Catalytic mechanism and pathways of 1, 2-dichloropropane oxidation over LaMnO3 perovskite: An experimental and DFT study.

The rational comprehension on the catalytic mechanism and pathways of chlorinated volatile organic compounds (CVOCs) oxidation is meaningful for the design of high performance catalytic materials. Herein, we attempted to elucidate the catalytic mechanism and pathways of 1, 2-dichloropropane (1, 2-DCP) oxidation over LaMnO3 perovskite from experimental and theoretical studies. Experimental results indicate that the initial dechlorination of 1, 2-DCP into allyl chloride (AC) can be readily achieved over LaMnO3, while the further decomposition of AC is more vulnerable to be affected by the reaction conditions and strongly dependent on the surface active oxygen species. Density functional theory (DFT) calculation reveals that the heterogeneous conversion of 1, 2-DCP initiates with the chemisorption on the Mn site, followed by the formation of AC via a synergistic mechanism. AC decomposition is considered as the rate-determining step under an inert condition, while the dechlorination of adsorbed 1, 2-DCP dominates the whole reaction under an oxygen atmosphere.

[Experimental expression of HIF-1α in rabbit adipose-derived mesenchymal stem cells by dynamic compression plus IGF-1 gene transfection].

OBJECTIVE: To investigate the effects on HIF-1α expression of rabbit adipose-derived mesenchymal stem cells (ADSCs) by dynamic compression plus IGF-1 gene transfection and explore the mechanism of promoting chondrogenesis by HIF-1α. METHODS: The ADSCs were harvested after the digestion of typeIcollagenase and transfection with pcDNA3.1-IGF-1. And then the cells were seeded onto chitosan/gelatin scaffolds with a density of 5 × 10(7) cells/ml and divided into groups: Group A (control), non-transfected ADSCs; Group B (IGF-1), hIGF-1 gene transfected ADSCs; Group C (loading), untransfected ADSCs with stimulation of compressive loading; Group D (loading + IGF-1), hIGF-1 gene transfected ADSCs and loading stimulation. The dynamic compression was carried out with a bio-reactor at a frequency of 0.1 Hz and a sinusoidal strain amplitude of 2% (2% at 0.1 Hz). The dynamic load was performed every 20 minutes, 4 hours daily. After 7 days, morphological observation was performed. The MTT assay was used to detect the cell proliferation. Meanwhile the CM-DiI cell-labeling solution was used to observe the distribution of cells. The total amount of GAG and the expression of related genes of IGF-1, HIF-1α, type II collagen (COL II) and Sox-9 were quantified. RESULTS: The best morphology was found in loading+ IGF-1 group. The results of proliferating capacity were: Group A < C < B < D (P < 0.01); Dil fluorescence showed that the cells were well-distributed in Group D. Meanwhile, the content of total GAG and the expression of related genes demonstrated: Group A < C < B < D (P < 0.01). And the combined effect was more significant than either alone. CONCLUSION: In three-dimensional culture conditions, dynamic compression plus IGF-1 transfection can significantly enhance the level of autocrine IGF-1. Both of two experimental intervention factors can significantly up-regulate the mRNA level of HIF-1α. And they exert a synergistic effect. HIF-1α plays an important role in promoting the chondrogenesis and the synthesis and secretion of extra-cellular matrix.

In-situ fabrication of a spherical-shaped Zn-Al hydrotalcite with BiOCl and study on its enhanced photocatalytic mechanism for perfluorooctanoic acid removal performed with a response surface methodology.

Perfluorooctanoic acid (PFOA), a widely used compound, is harmful to the environment and human health. In this study, a facile one pot solvothermal method of integrating BiOCl with Zn-Al hydrotalcite to form spherical-shaped BiOCl/Zn-Al hydrotalcite (B-BHZA) sample is reported. The characteristics and main factors affecting photocatalytic PFOA and photocatalytic mechanism of BiOCl/Zn-Al hydrotalcite (B-BHZA) are systematically investigated. It is found that spherical-shaped B-BHZA possesses abundant defects and a larger surface area of 64.4 m2 g-1. The factors affecting photocatalytic removal PFOA (e.g., time, pH, initial concentration and dosage) are investigated by modeling the 3D surface response. The removal rate of PFOA is over 90 % in 6 h under UV light at an optimal pH of 2, an initial concentration of 500 µg/L and a dose of dosage 0.5 g/L. The main mechanism occurs by photo-generated h+ oxidation and synergistic effects from the photocatalysis process. Though investigating the intermediates of PFOA degradation and F-, a possibility was proposed that h+ initiated the rapidly decarboxylation of PFOA. The unstable perfluoroheptyl group is formatted and further conversed to short chain perfluorocarboxylic acid. This study provides a new insight for the preparation of highly efficient photocatalysts to the treatment of halogenated compounds in UV system.