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In the present study, we aimed to investigate the clinical outcomes of arthroscopic discoid lateral meniscus (DLM) plasty and the adaptive changes in the patellofemoral joint after surgery. From September 2010 to March 2012, 25 patients with DLM injuries who underwent arthroscopic meniscus plasty were enrolled in the prospective study. All patients underwent clinical evaluation before the operation and at the last follow-up, and imaging evaluation was performed by upright magnetic resonance imaging before and 1 month after the operation as well as at the last follow-up. Clinical evaluation included Lysholm score, Kujala score, McMurray's sign, patellar mobility, patella grind test, and quadriceps atrophy. Imaging evaluation included bisect offset index, patella tilt angle (PTA), and cartilage damage. Lysholm score, Kujala score, McMurray's sign, and quadriceps atrophy at the last follow-up were significantly improved compared with the preoperative levels (P .05). At the last follow-up, there were no statistical differences in patella mobility and patella grind test compared with the preoperative levels. In addition, bisect offset index and PTA showed a dynamic trend of rising and then falling over time (P .05). At 1 month after the operation, bisect offset index and PTA were significantly increased compared with the preoperative levels or the values at the last follow-up (P .05), while there were no differences between the preoperation and the last follow-up. Cartilage damage became worse with time (P0.05), and the 2 were positively correlated (Spearman = 0.368). At the last follow-up, the degree of cartilage damage was significantly increased compared with the preoperative level (P .017), while there was no significant difference between the 1-month postoperative grade and the preoperational grade or the last follow-up grade. The effect of arthroscopic DLM plasty on the patellofemoral joint was dynamic, with the position of the patella deviating in the early stages and recovering in the mid-term, especially when the knee was in the biomechanical standing position. In addition, the patellofemoral joint cartilage might undergo accelerated degeneration after the operation, while the mid-term effect of the operation was positive, and the patellofemoral joint function was acceptable.

Unlike C–N bond formation with classical dirhodium(II)-nitrenoids as the key intermediate, dirhodium(II)-catalyzed 1,2- and 1,3-diamination reactions are realized by a free radical mechanism. A mechanistic study revealed that the reactions proceed through a radical-polar crossover process. UV-visible spectroscopy enables accurate observation of the change in the catalyst valence state during the reaction, which provides a basis for the rapid determination of the reaction end time based on the color change of the reaction solution.

A series of Cu(I)-enriched metal–organic frameworks (MOF) of the type CuBTC (BTC = benzene-1,3,5-tricarboxylate) was prepared by a mixed-linker defect engineering technique, namely substituting a portion of a parent linker with truncated pyridine-3,5-dicarboxylate (PyDC) in the synthesis process. The reduced carboxyl coordination sites and the emerged Lewis basic pyridyl sites of PyDC spawned mixed-valence Cu(I)–Cu(II) paddlewheels (PWs) in the defect-engineered CuBTC (DE-CuBTC) structure. Cu(I)-enriched DE-CuBTC shows significantly enhanced catalytic performance for the click reaction of azide–alkyne cycloaddition by accelerating the rate determining step of Cu(I)–acetylide intermediate formation. To further evaluate the catalytic activity of Cu(I)-enriched DE-CuBTC for reactions involving a Cu(I)–acetylide intermediate, the A3 coupling reaction of phenylacetylene, paraformaldehyde and piperidine was studied as well. This study shows that defect engineering is an effective editing tool of catalytic active sites in catalysts.

Dexmedetomidine (Dex) has been reported to exhibit neuroprotective effects through various regulatory mechanisms. This study aims to investigate the role and molecular mechanism of SNHG11 in Dex-mediated neuroprotection. The ischemic stroke (IS) model was established in vivo by middle cerebral artery occlusion (MCAO) and in vitro by oxygen-glucose deprivation and reperfusion (OGD/R)-treated SH-SY5Y. SNHG11 was highly expressed after OGD/R, and Dex improved OGD/R-induced neurological injury. Additionally, Dex reversed the effects of SNHG11 on OGD/R-induced neurological injury. Furthermore, we found that SNHG11 upregulated vascular endothelial growth factor A (VEGFA) expression by targeting miR-324-3p. Through rescue assays, it was confirmed that SNHG11 regulated OGD/R-induced neurological injury through increasing VEGFA expression. At last, Dex was also discovered to improve neurological injury through regulating SNHG11 in the rat model. In conclusion, our work demonstrated that Dex improved OGD/R-induced neurological injury via SNHG11/miR-324-3p/VEGFA axis. These findings may offer a novel therapeutic strategy for IS treatment.

The coupling of CO2 and epoxides is a promising way to reduce atmospheric carbon by converting it into value-added cyclic carbonate. Pursuing efficient catalysts is highly attractive for the title reaction. Herein, we developed simple and inexpensive catalyst systems of aliphatic carboxylic acids as the hydrogen-bond donor (HBD) and quaternary ammonium halides as the nucleophile to catalyze the CO2-epoxide coupling reaction with high efficiency and selectivity under mild conditions (80 °C and 4 bar CO2). The high activity of this catalyst system is retained even under ambient conditions. The effects of the acidity and steric hindrance of acids on the catalysis of CO2-epoxide coupling were systematically investigated. Lastly, the reaction mechanism was deduced and its rationality was further reinforced by exploring the interaction between a representative system AA/TBAB (acetic acid/tetrabutylammonium bromide) and propylene oxide (PO). The study of aliphatic carboxylic acids/quaternary ammonium halides provides a new way to design catalyst systems for the title reaction.

Defect engineering (DE) has been recognized as a powerful approach to tune the structural, optical, and chemical properties of metal–organic framework (MOF) materials. Here, a detailed characteriza...

Tuberculosis (TB) ranks as the leading cause of death from a single infectious agent (ranking more lethal than HIV/AIDS) over the course of the past decade. More concerning is that reports of multi-drug-resistant (MDR) and extensively drug-resistant (XDR) strains of TB have been dramatically increasing. It continues to become ever more clear that novel anti-TB drugs with improved efficacies and reduced toxicities are urgently needed. We report here the discovery of 12 new ilamycin analogues, ilamycins G-R (1-12), bearing various nonproteinogenic amino acids, along with ilamycins E1 (13) and F (14), from a 200 L scale culture of the marine-derived mutant actinomycete Streptomyces atratus SCSIO ZH16 ΔilaR. Importantly, bioassays against Mycobacterium tuberculosis H37Rv revealed that all 12 new agents displayed antitubercular activities with MIC values ranging from 0.0096 to 10 μM. The structures of 1-12 were elucidated on the basis of HRESIMS, 1D and 2D NMR, and X-ray single-crystal diffraction studies. In addition, compound 10 was found to be moderately cytotoxic against a panel of tumor human cell lines. From these data we can formulate tentative structure-activity relationships for the antitubercular and antitumor activities of the ilamycins.

Tuberculosis (TB) and its emerged drug resistance exert huge threats on the global health, therefore development of novel anti-TB antibiotics is very essential. Ilamycin-E1/E2 is a pair of cycloheptapeptide enantiomers obtained from a marine-derived Streptomyces atratus SCSIO ZH16-ΔilaR mutant, and become promising anti-TB lead compounds due to their significant anti-TB activities, but their low titer hampered the further clinical development. In this work, the statistical Plackett-Burman design (PBD) model was applied to screen out bacterial peptone as the only significant but negative factor affecting the ilamycin-E1/E2 production. Subsequent single factor optimization revealed that replacement of bacterial peptone with malt extract eliminated the accumulation of porphyrin-type competitive byproduct, and the titer of ilamycin-E1/E2 in shaking flasks was improved from original 13.6±0.8 to 142.7±5.7 mg/L for about 10.5 folds. Furthermore, a pH coordinated feeding strategy was first adopted in scaled-up production of ilamycin-E1/E2. The obtained titer of ilamycin-E1/E2 in 30L was 169.8±2.5 mg/L, while in 300L fermentor was only 131.5±7.5 mg/L due to the unsynchronization of feeding response and pH change. Therefore, the continuous pulse feeding strategy was further applied in 300L fermentor and finally achieved 415.7±29.2 mg/L ilamycin-E1/E2, which represented about 30.5 folds improvement at last. Our work provided the solid basis to achieve sufficient ilamycin-E1/E2 lead compounds and support their potential anti-TB drug development.

Tuberculosis (TB) ranks as the leading cause of death from a single infectious agent (ranking more lethal than HIV/AIDS) over the course of the past decade. More concerning is that reports of multi-drug-resistant (MDR) and extensively drug-resistant (XDR) strains of TB have been dramatically increasing. It continues to become ever more clear that novel anti-TB drugs with improved efficacies and reduced toxicities are urgently needed. We report here the discovery of 12 new ilamycin analogues, ilamycins G-R (

A series of new defect-engineered metal-organic frameworks (DEMOFs) were synthesized by framework doping with truncated linkers employing the mixed-linker approach. Two tritopic defective (truncated) linkers, biphenyl-3,3',5-tricarboxylates (LH) lacking a ligating group and 5-(5-carboxypyridin-3-yl)isophthalates (LPy) bearing a weaker interacting ligator site, were integrated into the framework of Cu2(BPTC) (NOTT-100, BPTC = biphenyl-3,3',5,5'-tetracarboxylates). Incorporating LH into the framework mainly generates missing metal node defects, thereby obtaining dangling COOH groups in the framework. However, introducing LPy forms more modified metal nodes featuring reduced and more accessible Cu sites. In comparison with the pristine NOTT-100, the defect-engineered NOTT-100 (DE-NOTT-100) samples show two unique features: (i) functional groups (the protonated carboxylate groups as the Bronsted acid sites or the pyridyl N atoms as the Lewis basic sites), which can act as second active sites, are incorporated into the MOF frameworks, and (ii) more modified paddlewheels, which provided extra coordinatively unsaturated sites, are generated. The cooperative functioning of the above characteristics enhances the catalytic performance of certain types of reactions. For a proof of concept, two exemplary reactions, namely, the cycloaddition of CO2 with propylene oxide to propylene carbonate and the cyclopropanation of styrene, were carried out to evaluate the catalytic activities of those DE-NOTT-100 materials depending on the defect structure.

Defect engineering is a strategy for tailoring the properties of metal-organic frameworks (MOFs). Plenty of efforts have been devoted to study the defect chemistry and structures of bulk MOFs; however, the reported example of a defect-engineered surface-mounted MOF (SURMOF) thin film is rare. In this work, defects were incorporated in SURMOF thin films by using defect-generating linkers and taking advantage of the liquid-phase stepwise epitaxial layer-by-layer growth (LBL). Two methods based on the LBL, named mixing method and alternating method, are proposed for incorporating defects in the prototypical SURMOF HKUST-1 by partially substituting the parent H3btc (benzene-1,3,5-tricarboxylic acid) linker with a set of defect-generating linkers H2ip (isophthalic acid), H2OH-ip (5-hydroxyisophthalic acid), and H2pydc (3,5-pyridinedicarboxylic acid). The crystallinity and phase purity of the obtained "defected" SURMOFs were confirmed by X-ray diffraction, infrared reflection absorption spectroscopy, and Raman spectroscopy. The incorporation of the defect-generating linkers and the types of induced defects were characterized by ultraviolet-visible spectroscopy, time-of-flight secondary ion mass spectrometry, methanol adsorption, scanning electron microscopy, and 1H nuclear magnetic resonance spectroscopy (after digestion of the samples). These two methods provide avenues for controlling the defect formation in MOF thin films.

A novel multifunctional drug delivery system has been constructed by assembling per-6-thio-β-cyclodextrin-modified ultrasmall CuS nanoparticles (CD-CuS) onto fluorescent AIEgen-containing mesoporous silica nanoparticles (FMSN). The CD-CuS nanoparticles are anchored on the surface of benzimidazole-grafted FMSN, acting as a gatekeeper and photothermal agent. The prepared blue-emitting nanocomposite (FMSN@CuS) exhibits good biocompatibility and cell imaging capability. Anticancer drug doxorubicin hydrochloride (DOX) molecules are loaded into FMSN@CuS, and zero prerelease at physiological pH (7.4) and on-demand drug release at an acidic environment can be achieved due to the pH-responsive gate-opening of CD-CuS only at an acidic condition. The FMSN@CuS nanocomposite can generate obvious thermal effect after the exposure of 808 nm laser, which can also accelerate the DOX release. Meanwhile, the fluorescence intensity of DOX-loaded FMSN@CuS increases with the release of DOX, and the intracellular drug release process can be tracked according to the change of luminescence intensity. More importantly, DOX-loaded FMSN@CuS displays efficient anticancer effects in vitro upon 808 nm laser irradiation, demonstrating a good synergistic therapeutic effect via combining enhanced chemotherapy and photothermal therapy.

Background To investigate the expression of long non-coding RNA (lncRNA) Snorna hostgene16 (SNHG16) in sciatic nerve injury tissues and cells. The molecular mechanism of SNHG16 regulating signal activator of transcription 3 (STAT3) expression through "sponge" adsorption of miR-93-5p was also studied. Methods A rat model of sciatic nerve injury was established, and primary Schwann cells (SCs) were extracted. The expression of SNHG16 in animal tissues with sciatic nerve injury and SCs treated with ischemia and hypoxia was detected by qPCR, and CCK-8 assay, cell scratch assay, and Transwell chamber assay were used to detect cell proliferation, migration, and invasion. The targeted binding of SNHG16 to miR-93-5p was verified by double luciferase reporter gene assay and miRNA immunoprecipitation assay. MiR-93-5p mimic, SNHG16 overexpression vector, and sh-STAT3 plasmid were transfected into cells, respectively, and the mRNA expressions of SNHG16, miR-93-5p, and STAT3 in the cells were detected by qPCR. Results The expression of lncRNA SNHG16 was decreased after sciatic nerve injury, while overexpression of SNHG16 promoted the proliferation, migration, and invasion of SCs. The results of dual luciferase reporter gene assay and miRNA immunoprecipitation reaction showed miR-93-5p interacted with SNHG16, and the overexpression of miR-93-5p reversed the promoting effects of SNHG16 on the proliferation and invasion of SCs. At the same time, the knockdown of STAT3, which is the target gene of miR-93-5p, reversed the proliferation and invasion promotion effect of SNHG16 on SCs. SNHG16 affected the expression of its downstream target gene STAT3 by adsorbing miR-93-5p via endogenous competitive sponge. Conclusions SNHG16 can regulate STAT3 expression by sponge adsorption of miR-93-5p in SCs, and SNHG16 and miR-93-5p can be used as potential targets for the diagnosis and treatment of sciatic nerve injury.

A multifunctional nanotheranostic system for imaging guided chemo- and photothermal synergistic therapy for cancer has been developed, in which the aggregation-induced emission (AIE) luminogen functionalised mesoporous silica nanoparticles (MSNs) act as anticancer drug carriers and biological imaging agents, and CuS nanoparticles attached to the silica nanosphere surface as the photothermal agent. The obtained nanocomposites (denoted as CFMSNs) exhibit a blue emission and have good biocompatibility, and can be used as an effective luminescent bioprobe for intracellular imaging. Furthermore, the nanoplatform can induce obvious thermal effects after the exposure to an 808 nm laser and serve as an effective pH-dependent NIR-responsive release system. More importantly, the combination of chemotherapy and photothermal therapy shows a better therapeutic effect than the individual therapies, thus demonstrating a synergistic action towards anticancer therapy.

Abies georgei var. smithii (Abies George I varsmithorr. II (Viguie et Gaussen) Cheng et l.) belongs to Abies of Pinaceae, which is distributed in the southeast of Tibet, southwest of Sichuan and northwest of Yunnan. In this study, Abies georgei var. smithii in Sejila Mountain of southeastern Tibet was studied, the contents of Malondialdehyde (MDA), proline (pro), hydrogen peroxide (H2O2), soluble sugar and chlorophyll as well as the activities of superoxide dismutase (SOD) and superoxide dismutase (SOD) in the leaves, twigs, tree stems and roots of Abies georgei var. smithii were measured at different altitudes in the growing and non-growing seasons, single factor analysis of variance and multiple comparison were used to process the data. The results showed that the contents of Malondialdehyde (MDA), proline (pro) and hydrogen peroxide (H2O2) in the roots of Abies georgei var. smithii were significantly higher than those of other tissues in both growing and non-growing seasons, the content of chlorophyll in the leaves increased at first and then decreased with the elevation gradient, on the contrary, the ratio of chlorophyll a/b (CHLA/CHLB) increased with the elevation gradient. The activities of Peroxidase (POD) and superoxide dismutase (SOD) were the lowest. When the altitude was more than 4300m, the activities of POD and SOD decreased. The results showed that the physiological resistance of Abies georgei var. smithii decreased when the elevation was over 3900m, which was not beneficial to the growth and development of Abies georgei var. smithii, therefore, the distribution of Abies georgei var. smithii along the higher elevation gradient was limited by the unfavorable environmental factors at high altitude.

Aggregation-induced emission (AIE) and aggregation-caused quenching (ACQ) materials are important for various fluorescence-based applications but cannot easily collaborate because of their opposite luminescence behaviours. Here, we demonstrate a strategy to integrate AIE and ACQ chromophores in periodic mesoporous organosilicas (PMOs) for high-efficiency multicolour emission. Tetraphenylethene (TPE)-bridged AIE-PMOs are prepared as hosts to encapsulate ACQ dyes (e.g. RhB), which enables fine-tuning of ACQ@AIE-PMO emissions over the entire visible spectrum in the solid and film states. Significantly, high-quality white light is achieved with CIE coordinates of (0.32, 0.33) and a quantum yield of up to 49.6%. Because of their high stability and solution processability, the ACQ@AIE-PMOs can be applied in solid-state lighting and bioimaging. This design concept opens up new perspectives for developing high-performance luminescent materials by the combination of a wide variety of AIE and ACQ chromophores.

Carrier antenna is the hub of communication between flight and ground station. This kind of antenna is generally curved conformal antennas and its spatial arrangement demands are high. In this paper, the contrast models are built on the plane and curved surface. By theoretical analysis and HFSS simulation, the influence of conformal surface and feeder bending on the performance of microstrip antenna are studied. The results show that the conformal surface will make the antenna performance worse, while the performance of the antenna is optimized with the feeder bending: conformal surface will make the resonance frequency offset, the S-parameter increased, which means more radiation loss and less radiation gain. On the contrary, feeder bending has little effect on the resonant frequency of the antenna, and at the same time, it can not only reduce the S-parameters, also increase the coverage area and gain value of antenna. These results provide a theoretical and simulation basis for the research and application of conformal microstrip antennas in the fields of communication and guidance.

Hollow mesoporous silica nanospheres functionalized with aggregation-induced emission (AIE) luminogen tetraphenylethene were prepared by postgrafting method. The as-prepared inorganic-organic hybrid nanospheres show bright blue emission and good biocompatibility as shown by MTT assays. The large cavities of the materials enable high loading of the anticancer drug doxorubicin hydrochloride (DOX), and the mesoporous silica shells allow pH-dependent drug release. The materials can be effectively taken up by cells and function as luminescent bioprobes, demonstrating their potential application in imaging-guided therapy.

Mesoporous silica nanoparticles functionalised with aggregation-induced emission (AIE) luminogen via a carbon–nitrogen double bond are fabricated into films by a dip-coating method. The as-made films can serve as efficient fluorescent sensors for the naked-eye detection of volatile acid gases by colour and emission changes, as well as for the detection of 2,4-dinitrotoluene vapours by fluorescence quenching.

To observe the effect of garlic oil combined with 5-FU induced apoptosis of adenoid cystic carcinoma cell line ACC-M.Human salivary in adenoid cystic carcinoma cell line AC-M was cultured, divided into the experimental group (5-FU group, garlic oil group, garlic oil + 5-FU group) and the control group, to observe the growth activity of tumor cells by MTT methods; to analyse the changes of cell cycle and apoptosis rate by flow cytometry.MTT experiments showed that 5-FU, garlic oil, garlic oil and 5-FU on ACC-M cells have inhibition in different concentration, with the increase of concentration and action time of the rise; Cell cycle analysis showed significant changes in flow cytometry. With the increase of concentration and the acting time, the G0/G1, phase of the cell ratio increased, S had no significant change, but G2/M phase cells decreased. Apoptosis rate display showed garlic oil combined with 5-FU induced apoptosis of ACC-M cells was significantly stronger than single group.Garlic oil can effectively induce the apoptosis of adenoid cystic carcinoma cell line ACC-M. The effect of garlic oil combined with 5-FU on ACC-M cells was stronger than the garlic oil, 5-FU used alone.

This paper addresses the problem of maximizing sensor networks lifetime as well as maintaining sufficient sensing coverage. To solve the problem, the calculation model of redundancy degree of the sensors whose sensing ranges satisfy the normal distribution without location information is proposed, and the calculation model of minimum of working nodes which can provide the desired quality of coverage (QoC) is also proposed. Based on the models, an Energy-Efficient and Coverage-Specific Node Scheduling for Wireless Sensor Networks (ECNS), which realizes collaborative scheduling of distributed nodes, is designed to guarantee the desired QoC with the least number of nodes and balance the energy consumption of each node. Simulation results show that ECNS can provide the desired QoC as well as reduce the total energy consumption effectively. In addition, ECNS can also make the energy consumption of each node homogeneously with low control overhead.