MGF6mARice: prediction of DNA N6-methyladenine sites in rice by exploiting molecular graph feature and residual block.

DNA N6-methyladenine (6mA) is produced by the N6 position of the adenine being methylated, which occurs at the molecular level, and is involved in numerous vital biological processes in the rice genome. Given the shortcomings of biological experiments, researchers have developed many computational methods to predict 6mA sites and achieved good performance. However, the existing methods do not consider the occurrence mechanism of 6mA to extract features from the molecular structure. In this paper, a novel deep learning method is proposed by devising DNA molecular graph feature and residual block structure for 6mA sites prediction in rice, named MGF6mARice. Firstly, the DNA sequence is changed into a simplified molecular input line entry system (SMILES) format, which reflects chemical molecular structure. Secondly, for the molecular structure data, we construct the DNA molecular graph feature based on the principle of graph convolutional network. Then, the residual block is designed to extract higher level, distinguishable features from molecular graph features. Finally, the prediction module is used to obtain the result of whether it is a 6mA site. By means of 10-fold cross-validation, MGF6mARice outperforms the state-of-the-art approaches. Multiple experiments have shown that the molecular graph feature and residual block can promote the performance of MGF6mARice in 6mA prediction. To the best of our knowledge, it is the first time to derive a feature of DNA sequence by considering the chemical molecular structure. We hope that MGF6mARice will be helpful for researchers to analyze 6mA sites in rice.

Chemoenzymatic Synthesis of Sterically Hindered Biaryls by Suzuki Coupling and Vanadium Chloroperoxidase Catalyzed Halogenations.

Halogenated biaryls are vital structural skeletons in bioactive products. In this study, an effective chemoenzymatic halogenation by vanadium-dependent chloroperoxidase from Camponotus inaequalis (CiVCPO) enabled the transformation of freely rotating biaryl bonds to sterically hindered axis. The yields were up to 84 % for the tribrominated biaryl products and up to 65 % when isolated. Furthermore, a one-pot, two-step chemoenzymatic strategy by incorporating transition metal catalyzed Suzuki coupling and the chemoenzymatic halogenation in aqueous phase were described. This strategy demonstrates a simplified one-pot reaction sequence with organometallic and biocatalytic procedures under economical and environmentally beneficial conditions that may inspire further research on synthesis of sterically hindered biaryls.

Synthesis of Imidazo[1,2-a]pyridine-Fused 1,3-Benzodiazepine Derivatives with Anticancer Activity via a One-Pot Cascade GBB-3CR/Pd(II)-Catalyzed Azide-Isocyanide Coupling/Cyclization Process.

A new one-pot synthesis of imidazo[1,2-a]pyridine-fused 1,3-benzodiazepine derivatives via a sequential GBB-3CR/Pd(II)-catalyzed azide-isocyanide coupling/cyclization process was developed. The Groebke-Blackburn-Bienaymé three-component reactions (GBB-3CR) of 2-aminopyridine, 2-azidobenzaldehydes, and isocyanides in the presence of a catalytic amount of p-toluenesulfonic acid gave azide intermediates without separation. The reaction was followed by using another molecule of isocyanides to produce imidazo[1,2-a]pyridine-fused 1,3-benzodiazepine derivatives in good yields by the Pd(II)-catalyzed azide-isocyanide coupling/cyclization reaction. The synthetic approach produces novel nitrogen-fused polycyclic heterocycles under mild reaction conditions. The preliminary biological evaluation demonstrated that compound 6a inhibited glioma cells efficiently, suggesting potentially broad applications of the approach for synthesis and medicinal chemistry.

Deep vein thrombosis in a patient with Cronkhite-Canada syndrome: a complex case report.

BACKGROUND: Cronkhite-Canada syndrome (CCS) is a rare disease characterized by generalized gastrointestinal polyps, ectodermal abnormalities and variable gastrointestinal symptoms. Few cases to date have described complications with deep vein thrombosis (DVT). Here we reported a rare case of CCS concomitant with DVT. The patient's clinical details, endoscopic findings, safety, and efficacy are reported. CASE PRESENTATION: A 58-year-old patient was admitted to our hospital with recurrent diarrhea, overall abnormal appearance, including hyperpigmentation, hair loss and onychodystrophy, and multiple polyps distributed along the gastrointestinal tract except the esophagus. After considerable assessment, the patient was diagnosed with CCS. She was also diagnosed with concurrent DVT, nephrotic syndrome, and infectious enteritis during the course of disease. After treatment with a combination of methylprednisolone, mesalazine, antibiotics, rivaroxaban, and nutritional support during the 24 months of following the patient in this case, the clinical manifestations and endoscopic findings reached complete remission two years after the diagnosis. CONCLUSION: To our knowledge, this study is the first case of CCS complicated with DVT reported in China. Although rare, it is important to consider that DVT may occur after CCS and that it is vital to conduct careful follow-up.

Circ_0008717 promotes renal cell carcinoma progression by upregulating FBXO17 via targeting miR-217.

BACKGROUND: Renal cell carcinoma (RCC) is a common lethal urological malignancy. Circular RNAs are assumed to play important roles in cancer development. The objective of the present study was to investigate the role and action mechanism of circ_0008717 in RCC. METHODS: The expression of circ_0008717, miR-217 and F-box protein 17 (FBXO17) mRNA was detected by a real-time quantitative polymerase chain reaction. Cell proliferation was examined using a cell counting kit-8 assay and an 5-ethynyl-2'-deoxyuridine assay. Cell apoptosis was assessed by a flow cytometry assay. Cell migration and cell invasion were investigated using a transwell assay. Glycolysis progression was assessed according to the levels of glucose uptake and lactate production. The expression of glycolysis-related proteins and FBXO17 protein was quantified by western blotting. The targets were analyzed by the bioinformatics tools (starBase and circinteractome) and validated by a dual-luciferase reporter assay, RNA pull-down assay and RNA immunoprecipitation assay. A xenograft model was established to monitor the role of circ_0008717 in vivo. RESULTS: Circ_0008717 was upregulated in RCC tissues and cells. Silencing circ_0008717 suppressed RCC cell proliferation, migration, invasion and glycolysis but promoted cell apoptosis. MiR-217 was a target of circ_0008717 and bound to the FBXO17 3' untranslated region. The expression of FBXO17 was positively regulated by circ_0008717 but impaired by miR-217 reintroduction. The inhibitory effects of circ_0008717 knockdown on RCC cell malignant behaviors were reversed by miR-217 inhibition or FBXO17 overexpression. Circ_0008717 knockdown inhibited tumor growth in vivo by regulating miR-217 and FBXO17. CONCLUSIONS: Circ_0008717 aggravated the progression of RCC by activating FBXO17 through targeting miR-217, which provided a novel mechanism for circ_0008717 to participate in RCC progression.

Synthesis of 4-Tetrazolyl-Substituted 3,4-Dihydroquinazoline Derivatives with Anticancer Activity via a One-Pot Sequential Ugi-Azide/Palladium-Catalyzed Azide-Isocyanide Cross-Coupling/Cyclization Reaction.

A new one-pot preparation of 4-tetrazolyl-3,4-dihydroquinazolines has been reported. The Ugi-azide reactions of 2-azidobenzaldehydes, amines, trimethylsilyl azide, and isocyanides produced azide intermediates without separation, which were treated with isocyanides to give 4-tetrazolyl-3,4-dihydroquinazoline derivatives through a sequential Palladium-catalyzed azide-isocyanide cross-coupling/cyclization reaction in moderate to good yields. The biological evaluation demonstrated that compound 6c inhibited breast cancer cells well and displayed broad applications for synthesis and medicinal chemistry.

Bridging the Functional and Wiring Properties of V1 Neurons Through Sparse Coding.

The functional properties of neurons in the primary visual cortex (V1) are thought to be closely related to the structural properties of this network, but the specific relationships remain unclear. Previous theoretical studies have suggested that sparse coding, an energy-efficient coding method, might underlie the orientation selectivity of V1 neurons. We thus aimed to delineate how the neurons are wired to produce this feature. We constructed a model and endowed it with a simple Hebbian learning rule to encode images of natural scenes. The excitatory neurons fired sparsely in response to images and developed strong orientation selectivity. After learning, the connectivity between excitatory neuron pairs, inhibitory neuron pairs, and excitatory-inhibitory neuron pairs depended on firing pattern and receptive field similarity between the neurons. The receptive fields (RFs) of excitatory neurons and inhibitory neurons were well predicted by the RFs of presynaptic excitatory neurons and inhibitory neurons, respectively. The excitatory neurons formed a small-world network, in which certain local connection patterns were significantly overrepresented. Bidirectionally manipulating the firing rates of inhibitory neurons caused linear transformations of the firing rates of excitatory neurons, and vice versa. These wiring properties and modulatory effects were congruent with a wide variety of data measured in V1, suggesting that the sparse coding principle might underlie both the functional and wiring properties of V1 neurons.

Multi-scroll hidden attractor in memristive HR neuron model under electromagnetic radiation and its applications.

This paper aims to propose a novel no-equilibrium Hindmarsh-Rose (HR) neuron model with memristive electromagnetic radiation effect. Compared with other memristor-based HR neuron models, the uniqueness of this memristive HR neuron model is that it can generate multi-scroll hidden attractors with sophisticated topological structures and the parity of the scrolls can be controlled conveniently with changing the internal parameters of the memristor. In particular, the number of scrolls of the multi-scroll hidden attractors is also associated with the intensity of external electromagnetic radiation stimuli. The complex dynamics is numerically studied through phase portraits, bifurcation diagrams, Lyapunov exponents, and a two-parameter diagram. Furthermore, hardware circuit experiments are carried out to demonstrate theoretical analyses and numerical simulations. From the perspective of engineering application, a pseudo-random number generator is designed. Besides, an image encryption application and security analysis are also performed. The obtained results show that the memristive HR neuron model possesses excellent randomness and high security, which is suitable for chaos-based real-world applications.

A simple no-equilibrium chaotic system with only one signum function for generating multidirectional variable hidden attractors and its hardware implementation.

This paper proposes a simple no-equilibrium chaotic system with only one signum function as compared with the existing no-equilibrium chaotic ones with at least one quadratic or higher nonlinearity. The system has the offset boosting of three variables through adjusting the corresponding controlled constants. The resulting hidden attractors can be distributed in a 1D line, a 2D lattice, a 3D grid, and even in an arbitrary location of the phase space. Particularly, a hidden chaotic bursting oscillation is also observed in this system, which is an uncommon phenomenon. In addition, complex hidden dynamics is investigated via phase portraits, time series, Kaplan-Yorke dimensions, bifurcation diagrams, Lyapunov exponents, and two-parameter bifurcation diagrams. Then, a very simple hardware circuit without any multiplier is fabricated, and the experimental results are presented to demonstrate theoretical analyses and numerical simulations. Furthermore, the randomness test of the chaotic pseudo-random sequence generated by the system is tested by the National Institute of Standards and Technology test suite. The tested results show that the proposed system has good randomness, thus being suitable for chaos-based applications such as secure communication and image encryption.

Metal-Free C-N or C-C Bond Cleavages of α-Azido Ketones: An Oxidative-Amidation Strategy for the Synthesis of α-Ketothioamides and Amides.

A novel metal-free oxidative-amidation strategy for the synthesis of α-ketothioamides and amides from α-azido ketones was developed. The C-H bond thionation of α-azido ketones with elemental sulfur could form α-ketothioacyl azide, which was then nucleophilically attacked by amines, causing the cleavage of the C-N bond to afford α-ketothioamides, while amides could be formed with the release of nitrogen gas and cyano anion in the presence of PhI(OAc)2 by selective C-C bond cleavage.

Synthesis and antiphytoviral activity of α-aminophosphonates containing 3, 5-diphenyl-2-isoxazoline as potential papaya ringspot virus inhibitors.

α-Aminophosphonates compounds containing 3,5-diphenyl-2-isoxazoline were synthesized and evaluated for their bioactivity. Seventeen of them showed good bioactivity (protection effect > 50%) in vivo against papaya ringspot virus, while two of them (V29 and V45) exhibited excellent antiviral activity (both 77.8%). In the latter case, the antiviral activity was close to that of antiphytovirucides ningnanmycin and dufulin (both 83.3%) at 500 mg/L. The preliminary structure-activity relationships indicated that the bioactivity was strongly influenced by the substituents.

Constructing multi-butterfly attractors based on Sprott C system via non-autonomous approaches.

In this paper, two different pulse control methods are proposed to generate multi-butterfly attractors based on the Sprott C system. By introducing a bipolar multilevel pulse signal to the boostable variable z of the Sprott C system, translational multi-butterfly attractors with constant Lyapunov exponents can be obtained. Another method for generating nested multi-butterfly attractors is to replace the DC voltage of the Sprott C system with the unipolar multilevel pulse signal, and the dynamical behavior involves the superposition of multiple attractors corresponding to different pulse amplitudes. By defining time as an additional state variable, the proposed non-autonomous systems can be transformed into autonomous systems for analysis. It can be seen that systems have no equilibria, so they belong to hidden attractors. A normalized circuit implementation is given, translational and nested hidden multi-butterfly attractors can be obtained by setting proper pulse signals. Moreover, the number of butterflies can be adjusted by changing the number of pulse voltage sources without reconstructing nonlinear functions. Theoretical analysis and simulation results prove the effectiveness of these methods.

Light enhanced room temperature resistive NO2 sensor based on a gold-loaded organic-inorganic hybrid perovskite incorporating tin dioxide.

A material is described for sensing NO2 in the gas phase. It has an architecture of type Au/MASnI3/SnO2 (where MA stands for methylammonium cation) and was fabricated by first synthesizing Au/MASnI3 and then crystallizing SnO2 on the surface by calcination. The physical and NO2 sensing properties of the composite were examined at room temperature without and with UV (365 nm) illumination, and the NO2-sensing mechanism was studied. The characterization demonstrated the formation of a p-n heterojunction structure between p-MASnI3 and n-SnO2. The sensor, best operated at a voltage of 1.1 V at room temperature, displays superior NO2 sensing performance. Figures of merit include (a) high response (Rg/Ra = 240 for 5 ppm NO2; where Rg stands for the resistance of a sensor in test gas, and Ra stands for the resistance of a sensor in air), (b) fast recovery (about 12 s), (c) excellent selectivity compared to sensors based on the use of SnO2 or Au/SnO2 only, both at room temperature under UV illumination; (d) a low detection limit (55 ppb), and (e) a linear response between 0.5 and 10 ppm of NO2. The enhanced sensing performance is mainly attributed to the high light absorption capacity of MASnI3, the easy generation and transfer of photo-induced electrons from MASnI3 to the conduction band of SnO2, and the catalytic effect of gold nanoparticles. Graphical abstract Schematic of the energy band diagrams of the gold-functionalized MASnI3/SnO2 system after equilibrium with UV illumination, by which the enhanced sensing performance for NO2 can be explained.

Intraoperative serious complications of laparoscopic urological surgeries: a single institute experience of 4,380 procedures.

This study aimed to share a single institute experience of 4,380 procedures about intraoperative serious complications of laparoscopic urological surgeries. From January 2005 to December 2013, 4,380 cases of laparoscopic urological surgeries were recruited in our department. The distribution, incidence, and characteristics of intraoperative serious complications were retrospectively sorted out and analyzed. The surgeries were divided into three groups: very difficult (VD), difficult (D), and easy (E). The complication at Satava class II was defined to be serious. One hundred thirty one cases with intraoperative serious complications were found (3.0%). The incidence of these complications was significantly increased along with the difficulty of the surgeries (P<0.05). The highest morbidity of serious complication belonged to total cystectomy with a ratio of about 17% as compared with other surgeries (P<0.05). The types of these complications included small vascular injury demanding blood transfusion (101 cases, 77.1%), large vascular (venous and artery) injury (16 cases), hypercapnia & acidosis (8 cases), and organ injury (6 cases). The cases of conversion to open surgery were 37 (≤1%). There was no significant difference in the rates of conversion to open surgery among the three groups (P>0.05). The overall tendency of the intraoperative serious complications was decreasing with the time from 2005 to 2013. In conclusion, through standardized training including improving the surgical technique, being familiar with the anatomic relationship, and constantly summarizing the experience and lessons, laparoscopic surgery could be safe and effective with not only minimal invasion but also few complications.

Formation of n-n type heterojunction-based tin organic-inorganic hybrid perovskite composites and their functions in the photocatalytic field.

MASnI3/TiO2 composites (MA represents CH3NH3+) are prepared via a solvothermal method and characterized by various techniques. The results indicate that n-n type heterojunction structures and different ohmic contact interfaces are formed for the composites with different contents of MASnI3 and TiO2 before and after calcination, resulting in different optical and photocatalytic performances. Generally speaking, n-n type heterojunctions play roles in photocatalytic applications through two different mechanisms: the heterojunction mechanism and the Z-type mechanism. The calcined composites with better ohmic contact interfaces mainly follow the Z-type mechanism, which can promote direct radiative recombination of photogenerated carriers. As a result, higher luminous intensities and interface recombination instead of bulk recombination between electrons and holes can be achieved, which improves the photoluminescence and photocatalytic activities of the materials. Moreover, the n-n type heterojunction structure avoids p-type defect states to some degree, which averts the hydrolysis and oxidation of MASnI3 in atmosphere and enhances the long-term stability of the MASnI3/TiO2 composites.

[Macrophages depletion impairs skeletal muscle regeneration by regulating inflammation and oxidative stress levels].

The objective of this study was to explore the roles of macrophages in the regeneration of injured skeletal muscle and the mechanisms involved. Mice were randomly divided into the following groups: muscle contusion (S), muscle contusion control (SCon), macrophages depleted (T) and macrophages depleted control (TCon) groups. Muscle contusion model was created by high-energy blunt injury. Macrophages depletion model was constructed by injection of clodronate-liposomes. Their gastrocnemius muscles were harvested at the time points of 1, 3, 7 and 14 d post-injury. The changes in skeletal muscle morphology were assessed by hematoxylin-eosin (HE) staining and Masson's trichrome staining. The mRNA and protein levels of inflammatory cytokines, chemokines and oxidative stress factors were analyzed by real-time polymerase chain reaction (RCR) and Western blotting, respectively. HE staining results showed that a small amount of regenerating myofibers were observed in the S group (14 d post-injury), whereas a large number of regenerating muscle fibers were observed in the T group. Quantitative analyses showed that the sizes of regenerating myofibers were significantly smaller in the T group as compared with the S group at 14 d post-injury (P < 0.05). At the same time, Masson staining results showed that macrophage depletion significantly increased the area of fibrosis as compared with the S group at 14 d post-injury (P < 0.01). The expression levels of inflammatory cytokines, chemokines, and oxidative stress factors were increased significantly after muscle injury. Moreover, macrophage depletion increased the expressions of inflammatory cytokines, chemokines and oxidative stress factors as compared with the S group during the later stage of injury (7-14 d post-injury). These results suggest that macrophages depletion can aggravate fibrosis and impair muscle regeneration, and inflammatory cytokines, chemokines and oxidative stress factors may be involved in this process.

Multistability of Delayed Recurrent Neural Networks with Mexican Hat Activation Functions.

This letter studies the multistability analysis of delayed recurrent neural networks with Mexican hat activation function. Some sufficient conditions are obtained to ensure that an [Formula: see text]-dimensional recurrent neural network can have [Formula: see text] equilibrium points with [Formula: see text], and [Formula: see text] of them are locally exponentially stable. Furthermore, the attraction basins of these stable equilibrium points are estimated. We show that the attraction basins of these stable equilibrium points can be larger than their originally partitioned subsets. The results of this letter improve and extend the existing stability results in the literature. Finally, a numerical example containing different cases is given to illustrate the theoretical results.

Macrophage depletion impairs skeletal muscle regeneration: The roles of regulatory factors for muscle regeneration.

Though macrophages are essential for skeletal muscle regeneration, which is a complex process, the roles and mechanisms of the macrophages in the process of muscle regeneration are still not fully understood. The objective of this study is to explore the roles of macrophages and the mechanisms involved in the regeneration of injured skeletal muscle. One hundred and twelve C57BL/6 mice were randomly divided into muscle contusion and macrophages depleted groups. Their gastrocnemius muscles were harvested at the time points of 12 h, 1, 3, 5, 7, 14 d post-injury. The changes in skeletal muscle morphology were assessed by hematoxylin and eosin (HE) stain. The gene expression was analyzed by real-time polymerase chain reaction. The data showed that CL-liposomes treatment did affect the expression of myogenic regulatory factors (MyoD, myogenin) after injury. In addition, CL-liposomes treatment decreased the expression of regulatory factors of muscle regeneration (HGF, uPA, COX-2, IGF-1, MGF, FGF6) and increased the expression of inflammatory cytokines (TGF-ß1, TNF-α, IL-1ß, RANTES) in the late stage of regeneration. Moreover, there were significant correlations between macrophages and some regulatory factors (such as HGF, uPA) for muscle regeneration. These results suggested that macrophages depletion impairs skeletal muscle regeneration and that the regulatory factors for muscle regeneration may play important roles in this process.

Electrical Transport Properties of Au Nanoparticles and Thin Films on Ge Probed Using a Conducting Atomic Force Microscope.

In this work, gold nanoparticles (Au NPs) were distributed on an n-Ge substrate using the colloidal NP deposition method to form Au NP/Ge Schottky diodes (SDs), and the current transport properties of these nano-SDs were studied. The current density-voltage (J-V) characteristics were measured on each nanometer-sized Au particle using a conducting atomic force microscope (C-AFM). These Au NP/Ge diodes showed a rectifying behavior. According to the thermionic emission (TE) model, the effective Schottky barrier height (SBH) and ideality factors n were obtained. The SBH for the Au NP/Ge diodes ranges from 0.22 to 0.30 eV and the ideality factor ranges from 3.8 to 8.6. The current density and the barrier height increase while the ideality factor decreases with increasing Au NP diameters. This indicates that the tunneling effect is enhanced because of the narrowed depletion width and decreased size of the Au NP/Ge SDs. To compare the electrical behavior with Au NP/Ge diodes, the Au thin film/Ge diodes were also prepared and their SBHs were much larger because of the image-charge lowering effect and the tunneling effect in Au NP/Ge diodes.

Sphingobacterium griseoflavum sp. nov., isolated from the insect Teleogryllus occipitalis living in deserted cropland.

A Gram-stain-negative, aerobic, rod-shaped, non-motile bacterial strain, designated SCU-B140T, was isolated from the insect Teleogryllus occipitalis. Phylogenetic analysis on the basis of 16S rRNA gene sequence showed that strain SCU-B140T belonged to the genus Sphingobacterium. Sphingobacterium bambusae KCTC 22814T (97.87 %) was identified as the most closely related phylogenetic neighbour of strain SCU-B140T. The novel strain was able to grow at salt concentrations of 0-4 % (w/v), at temperatures of 10-40 °C, and at a pH of 6.0-9.0. The major cellular fatty acids were iso-C15 : 0, summed feature 3 (iso-C15 : 0 2-OH and/or C16 : 1ω7c), C16 : 0, C16 : 0 3-OH, C18 : 0 and C14 : 0. The major polar lipids consisted of phosphatidylethanolamine, three unknown aminophospholipids, an unknown glycolipid and three unknown polar lipids. MK-7 was the major isoprenoid quinone. The DNA G+C content was 41.2 mol%. The DNA-DNA relatedness value between SCU-B140T and S. bambusae KCTC 22814T was found to be 30.15 %. According to these results, strain SCU-B140T represents a novel species of the genus Sphingobacterium, for which the name Sphingobacterium griseoflavum sp. nov. is proposed. The type strain is SCU-B140T ( = KCTC 42158T = CGMCC 1.12966T).