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The research aimed to efficiently prepare zinc caprylate using caprylic acid and zinc sulfate as raw materials and explore its antibacterial effects and mechanisms. The experiment employed a saponification and complex decomposition method to chelate caprylic acid with zinc sulfate to generate zinc caprylate, followed by structural characterization. Staphylococcus aureus and Escherichia coli were chosen as models, and the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined by a two-fold dilution method to investigate the antibacterial activity of zinc caprylate. The study also examined the impact of zinc caprylate on the cell membrane permeability, biofilm formation, DNA, and protein synthesis of Staphylococcus aureus and Escherichia coli to elucidate its antibacterial mechanism. The results showed that zinc caprylate had a well-defined crystal structure with uniform particle size. It exhibited strong antibacterial effects against both Staphylococcus aureus and Escherichia coli, with the MIC values of 250 and 350 mg/L, respectively, and a stronger inhibitory effect on Staphylococcus aureus. Zinc caprylate disrupted the cell membrane permeability of Staphylococcus aureus and Escherichia coli in a time-dependent manner, inhibited the formation of bacterial biofilms, thus exerting antibacterial effects. However, the impact on DNA and protein synthesis in both Escherichia coli and Staphylococcus aureus was not significant. The study suggests that zinc caprylate demonstrates strong antibacterial activity against both Gram-positive and Gram-negative bacteria by inhibiting biofilm formation and disrupting cell membrane permeability. It holds potential as a substitute for antibiotics in livestock and poultry production. [ABSTRACT FROM AUTHOR]

Background: The conversion of phytosterols to steroid synthons by engineered Mycolicibacteria comprises one of the core steps in the commercial production of steroid hormones. This is a complex oxidative catabolic process, and taking the production of androstenones as example, it requires about 10 equivalent flavin adenine dinucleotide (FAD). As the high demand for FAD, the insufficient supply of FAD may be a common issue limiting the conversion process. Results: We substantiated, using the production of 9α-hydroxy-4-androstene-3,17-dione (9-OHAD) as a model, that increasing intracellular FAD supply could effectively increase the conversion of phytosterols into 9-OHAD. Overexpressing ribB and ribC, two key genes involving in FAD synthesis, could significantly enhance the amount of intracellular FAD by 167.4% and the production of 9-OHAD by 25.6%. Subsequently, styrene monooxygenase NfStyA2B from Nocardia farcinica was employed to promote the cyclic regeneration of FAD by coupling the oxidation of nicotinamide adenine dinucleotide (NADH) to NAD+, and the production of 9-OHAD was further enhanced by 9.4%. However, the viable cell numbers decreased by 20.1%, which was attributed to sharply increased levels of H2O2 because of the regeneration of FAD from FADH2. Thus, we tried to resolve the conflict between FAD regeneration and cell growth by the overexpression of catalase and promotor replacement. Finally, a robust strain NF-P2 was obtained, which could produce 9.02 g/L 9-OHAD after adding 15 g/L phytosterols with productivity of 0.075 g/(L h), which was 66.7% higher than that produced by the original strain. Conclusions: This study highlighted that the cofactor engineering, including the supply and recycling of FAD and NAD+ in Mycolicibacterium, should be adopted as a parallel strategy with pathway engineering to improve the productivity of the industrial strains in the conversion of phytosterols into steroid synthons. [ABSTRACT FROM AUTHOR]

Radix Asteris (RA), also known as 'Zi Wan', is the dried root and rhizome of Aster tataricus L. f., which has been used to treat cough and asthma in many countries such as China, Japan, Korea and Vietnam. This article summarizes the available information on RA in ancient Chinese medicine books and modern research literature: its botanical properties, traditional uses, chemical composition, pharmacological activity, toxicity and quality control. Studies have shown that RA extracts contain terpenes, triterpenoid saponins, organic acids, peptides and flavonoids, and have various pharmacological activities such as anti-inflammatory, anti-tumor, anti-oxidation, and anti-depression. RA is considered to be a promising medicinal plant based on its traditional use, chemical constituents and pharmacological activities. However, there are few studies on its toxicity and the consistency of its components, which indicates the need for further in-depth studies on the toxicity and quality control of RA and its extracts. [ABSTRACT FROM AUTHOR]

The flow behavior of three-dimensional (3D) dendrite growth with random preferred angle under natural convection was studied by using the Lattice Boltzmann-Cellular Automata (LB-CA) method with dynamic and static grids. In this model, the temperature field, flow field and solute field calculated by Lattice Boltzmann method (LBM) and dendrite growth calculated by CA method were carried out in static and dynamic grids respectively, and the coupling between LBM and CA was performed by interpolation of calculation parameters between dynamic and static grids. Results show that the asymmetry of solid phase distribution makes the streamline distribution more complex. At the initial stage of multiple dendrites growth, the fluid flow is relatively free. When dendrites grow close to each other, the fluid flow is blocked and can only flow along the gap between dendrites. During the wall equiaxed-columnar-central equiaxed crystals transformation (ECET) process, dense eddy current is formed at the wall equiaxed crystals at first. Then, when the wall equiaxed crystals gradually develop into columnar crystals, the eddy current moves with the solid-liquid interface. When the central equiaxed crystals are formed, the eddy current at the front of the columnar crystals gradually disappears. New eddies appear as the central equiaxed crystal grows. [ABSTRACT FROM AUTHOR]

• Identified a 22-gene prognostic signature related to lysosomes and senescence using TCGA gastric cancer data. • Classified gastric cancers into two subtypes, Cluster 1 and Cluster 2, based on the 22 genes, with Cluster 2 exhibiting worse prognosis. • Cluster 2 displayed widespread dysregulation of lysosomal and senescence pathways, associated with higher clinical stage and activated oncogenic signaling like PI3K-Akt. • MMP12 was downregulated in Cluster 2, and cellular experiments suggested a protective role in gastric cancer. As humans undergo the aging process, they become more vulnerable to various types of cancers, including gastric cancer (GC), which is frequently associated with aging. The senescent phenotype is closely linked to lysosomes, but research on the combined impact of senescence and lysosomes on GC prognosis is scarce. To construct and validate a prognostic model for gastric cancer (GC), we obtained gene expression and clinical data of GC patients from Cancer Genome Atlas (TCGA) databases. We employed Least Absolute Shrinkage and Selection Operator (LASSO) Cox regression for model construction and ConsensusClusterPlus R package for generating cluster heatmaps. The model's predictive ability was evaluated through Kaplan-Meier survival analysis and ROC curve analysis. Our analysis included an assessment of the senescence and lysosome state using expression profiles and immune infiltration analysis through CIBERSORT methods. Finally, we validated potential gene targets through cellular experiments. "In this research, we discovered two subtypes of gastric cancer (GC), Cluster 1 and Cluster 2. These subtypes are characterized by the presence of lysosomes and senescence, and we have identified distinct molecular features unique to each subtype. We observed that Cluster 2 had a lower survival prognosis compared to Cluster 1. Additionally, we have developed a risk prediction model that takes into consideration the presence of lysosomes and senescence. Patients in the high-risk group, as predicted by our model, experienced shorter survival times. Further analysis included immune infiltration, immune checkpoint, and chemotherapy evaluation of GC patients. We have displayed the frequency of mutations and copy number variations (CNVs) in visual formats. Our cellular experiments demonstrated that the MMP12 gene serves as a protective factor in GC cells." In conclusion, we have clarified the extensive relationship between lysosomes and senescence in GC and developed a risk signature to forecast the prognosis of GC patients. MMP12 could be a promising protective factor for GC patients and might present a novel concept for anticipating the efficacy of targeted therapies and immunotherapies in GC patients. [ABSTRACT FROM AUTHOR]

A continuous-flow electrochemical synthesis platform has been developed to enable self-optimization of reaction conditions of organic electrochemical reactions using attenuated total reflection Fourier transform infrared spectroscopy (ATR FT-IR) and gas chromatography (GC) as online real-time monitoring techniques. We have overcome the challenges in using ATR FT-IR as the downstream analytical methods imposed when a large amount of hydrogen gas is produced from the counter electrode by designing two types of gas–liquid separators (GLS) for analysis of the product mixture flowing from the electrochemical reactor. In particular, we report an integrated GLS with an ATR FT-IR probe at the reactor outlet to give a facile and low-cost solution to determining the concentrations of products in gas–liquid two-phase flow. This approach provides a reliable method for quantifying low-volatile analytes, which can be problematic to be monitored by GC. Two electrochemical reactions the methoxylation of 1-formylpyrrolidine and the oxidation of 3-bromobenzyl alcohol were investigated to demonstrate that the optimal conditions can be located within the pre-defined multi-dimensional reaction parameter spaces without intervention of the operator by using the stable noisy optimization by branch and FIT (SNOBFIT) algorithm. Graphical Abstract [ABSTRACT FROM AUTHOR]

ta-C thin films were deposited by vacuum cathodic arc technology with an unbalanced external electromagnetic field. The intensity of the magnetic field was adjusted by changing coil current and its effect on structure and properties of ta-C films was studied. FEM simulation results showed that as coil currents increased, the transverse, normal magnetic field and the magnetic intensity from arc cathode to substrates holder gradually increased. The UBM system increases the magnetic field intensity of the entire vacuum chamber by mainly improving the normal magnetic flux density near the arc cathode. The surface morphology, microstructure, tribo-mechanical properties of ta-C films were analyzed by SEM, Raman spectrometer, XPS, 3D surface profiler, Nano-indentation and ball-on-disk tribometer. Results showed that as the coil current increased, the average target voltage increased from 21.14 V to 25.97 V and target power rose from 845 W to 1043 W. Changes of magnetic field affected the plasma in vacuum chamber and the number of ions reaching the substrates, which had significant influences on film structure and properties. With a proper magnetic field (at coil current of 4A), ta-C films perform the highest hardness of 58.8 GPa, and the highest sp3 content of about 71% with the lowest ratio of I D /I G (0.38). During the wear process, the transfer layer was formed by oxidation and graphitization of contact surfaces. High hardness provided good support for transfer film, which leads to a low wear rate. [ABSTRACT FROM AUTHOR]

Industrial Wireless Networks (IWNs) play a critical role in industry 4.0 applications. However, industrial control processes require deterministic data delivery with an extremely high reliability, which is challenging in harsh IWN environments. Existing scheduling schemes rely mainly on accurate global synchronization to ensure deterministic transmission, which incurs additional hardware cost and a large communication overhead. To eliminate the synchronization requirements, we propose an asynchronous scheduling model that supports arbitrary time offset between any node pairs. As finding a solution with a given reliability guarantee in this model is a NP-hard problem, we design a probabilistic algorithm based on the Monte Carlo tree search (MCTS) method to generate and verify feasible schedules. The simulation results show that E-MCTS is significantly better in transmission reliability if compared to the classic Monte Carlo tree search algorithm. [ABSTRACT FROM AUTHOR]

An efficient electrochemical radical silyl‐oxygenation of electron‐deficient alkenes is demonstrated, which gives access to a variety of new highly functionalized silicon‐containing molecules, including β‐silyl‐cyanohydrin derivatives in good yields with excellent chemo‐ and regio‐selectivity. This electrochemical radical silylation process conducts under mild conditions without the use of transition metal catalyst or chemical oxidant and exhibits a wide scope of substrate silanes with high functional‐group tolerance. The ability to access silyl radicals using electrochemical Si−H activation offers new perspectives for the synthesis of valuable organosilicon compounds in a sustainable and green manner. [ABSTRACT FROM AUTHOR]

An efficient electrochemical radical silyl‐oxygenation of electron‐deficient alkenes is demonstrated, which gives access to a variety of new highly functionalized silicon‐containing molecules, including β‐silyl‐cyanohydrin derivatives in good yields with excellent chemo‐ and regio‐selectivity. This electrochemical radical silylation process conducts under mild conditions without the use of transition metal catalyst or chemical oxidant and exhibits a wide scope of substrate silanes with high functional‐group tolerance. The ability to access silyl radicals using electrochemical Si−H activation offers new perspectives for the synthesis of valuable organosilicon compounds in a sustainable and green manner. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: An anodic oxidation enabled synthesis of hypervalent iodine(III) reagents from aryl iodides is demonstrated. Under mild electrochemical conditions, a range of aryliodine(III) reagents including iodosylarenes, (difunctionaliodo)arenes, benziodoxoles and diaryliodonium salts can be efficiently synthesized and derivatized in good to excellent yields with high selectivity. As only electrons serve as the oxidation reagents, this method offers a more straightforward and sustainable manner avoiding the use of expensive or hazardous chemical oxidants. [ABSTRACT FROM AUTHOR]

To facilitate the cell-based experiment for pulsed electromagnetic field biological effect study, a novel TEM-cell-integrated CO2 incubator was developed. The integrated experimental system could simultaneously meet the requirement of standard cell culture condition and the various Transient Electromagnetic Field (TEF) exposure, which made it possible to study the relationship between different electromagnetic pulse exposure and the cellular responses in a reliable way. During the research, a comparison experiment was carried out to evaluate the necessity of the integrated incubator system: firstly, two different types of cell lines, which are the human prostate cancer cell line (PC3) and the pancreatic β cell line (MIN6) were chosen and exposed in the TEM-cell which located in the open area and the integrated system, respectively, with the same EFT radiation conditions; then, the cells' viability, the cellular ROS level and the mitochondrial membrane potential (MMP) were detected, respectively. The results showed that in the same parameter of the EFT radiation, the processes of the cells had a significant difference and even opposite in the incubator and open area, and all the results could be reproducible. The phenomenon indicated the stability of the TEM-cell-integrated CO2 incubator, and also demonstrated the necessity to strictly control the cell culture condition when carrying out the precise mechanism study of the TEF bioresponse at the cellular levels. [ABSTRACT FROM AUTHOR]

It is a necessity to evaluate the susceptibility of electronics to transient electromagnetic disturbances, such as electromagnetic pulses, lightning, electro-static discharges, and switching pulses. One can conduct experiments on the system of interest and analyze the result through statistical inference for the relationship between electromagnetic excitations and effect phenomena. However, since conventional statistical models are driven by experimental data, it might result in inappropriate explanations of the effect mechanisms due to limited samples, leading to over- or under-estimations. To address this problem, we propose a hybrid model that combines the statistical estimation with the known failure mechanism obtained from either the theoretical analysis or the empirical evidence. The physical cause can be drawn from the mechanism analysis, and then a statistical classifier is introduced to build the relationship between the causes and the effects. Based on Bayesian assessment, all the parameters involved are estimated with the Markov chain Monte Carlo method. Numerical simulation results have verified that the model is capable of estimating the susceptibility of electronics with given failure mechanism assumptions and limited test samples. In the end, the breakdown characteristic of the gas discharge tube is investigated to demonstrate the applicability of the proposed model. [ABSTRACT FROM AUTHOR]

Communication errors can be caused by transient electromagnetic disturbances, making the related protection and avoidance measures highly demanding. In this article, we propose a statistical method to infer error mechanisms of serial communication errors caused by repetitive electromagnetic disturbances. An experimental investigation has been conducted by introducing crosstalk disturbances on the transmission cable, resulting in various communication errors. To determine the corresponding failure mechanism for these errors, a hypothesis test method is introduced. First, the bit-flip error on the basis of the known mechanism is simulated through the Monte Carlo method, so that a null hypothesis can be established. Then, by applying a modified chi-squared test, researchers can investigate the influence of multiple pulses on the occurrence probability of bit errors. As a result, nonlinear effects such as energy saturation or accumulation of the transceivers can be discovered. The validated results show that the proposed method has a good performance to determine the known mechanisms of communication errors and infer new regularities with a given significant level. [ABSTRACT FROM AUTHOR]

Gorham-Stout syndrome (GSS) is a rare disease characterized by spontaneous and progressive osteolysis caused by benign proliferation of lymphatic vessels or capillaries. It most commonly occurs in children or young individuals without any inherited predisposition. GSS most commonly affects the shoulder girdle, pelvis, ribs and skull. Its diagnosis is mainly based on radiological and pathological findings. The present study reports on the case of a 22-year-old male patient diagnosed with GSS involving the C1-T1 vertebrae accompanied by bilateral pleural effusion. Resection of the occipital and cervical vertebral lesions and spinal reconstruction using an internal fixator were successfully performed via the posterior approach. After the surgery, the patient received bisphosphonate treatment and vitamin D supplementation. The pleural effusion gradually decreased. At the 18-month follow-up visit, no evidence of new bone obstruction was present and the patient had no neurological sequelae. [ABSTRACT FROM AUTHOR]

Exploitation of efficient and stable photocatalyst for water splitting is pressing to solve the energy crisis. Four CdS@MoS2 nano‐heterojunctions were prepared by a single precursor thermal decomposition combined with one‐step hydrothermal method. The morphology of the prepared samples is spherical and has obvious core‐shell structure interface. The photocurrent of CdS@MoS2‐2 wt% is the largest, which is more over 40 times that of the pure CdS. In addition, CdS@MoS2‐2 wt% had superior photocatalytic H2 generation activity (20.23 mmol g−1 h−1) without any noble metal as a cocatalyst under visible light and show marked photocatalytic durability after a continuous test for 16 hours. This work provides a new insight for the design of core‐shell nano‐heterojunctions for other metal sulfide composites. [ABSTRACT FROM AUTHOR]

Schematic representation of intrinsic apoptotic pathway induced by Sinularin relied on FOXO3 in prostate cancer cells. Sinularin upregulates FOXO3 via inhibiting the activity of AKT and ERK which phosphorylate FOXO3 at Ser253 and Ser294 respectively. Phosphorylation at these sites leads to FOXO3 binding to 14-3-3 protein, FOXO3 translocation to cytoplasm from nucleus, and subsequent ubiquitin–proteasome degradation. The upregulated FOXO3 increased its target PUMA, a pro-apoptotic protein belonging to the BH3 sub-family of Bcl-2 family. PUMA binds and antagonizes Bcl-2, then leads to mitochondrial outer membrane permeabilization and mitochondrial membrane potential collapses, promoting cytochrome c release and apoptosis. [Display omitted] Sinularin, a natural product that purified from soft coral, exhibits anti-tumor effects against various human cancers. However, the mechanisms are not well understood. In this study, we demonstrated that Sinularin inhibited the viability of human prostate cancer cells in a dose-dependent manner and displayed significant cytotoxicity only at high concentration against normal prostate epithelial cell RWPE-1. Flow cytometry assay demonstrated that Sinularin induced tumor cell apoptosis. Further investigations revealed that Sinularin exerted anti-tumor activity through intrinsic apoptotic pathway along with up-regulation of pro-apoptotic protein Bax and PUMA, inhibition of anti-apoptotic protein Bcl-2, mitochondrial membrane potential collapses, and release of mitochondrial proteins. Furthermore, we illustrated that Sinularin induced cell apoptosis via up-regulating PUMA through inhibition of FOXO3 degradation by the ubiquitin–proteasome pathway. To explore how Sinularin suppress FOXO3 ubiquitin–proteasome degradation, we tested two important protein kinases AKT and ERK that regulate FOXO3 stabilization. The results revealed that Sinularin stabilized and up-regulated FOXO3 via inhibition of AKT- and ERK1/2-mediated FOXO3 phosphorylation and subsequent ubiquitin–proteasome degradation. Our findings illustrated the potential mechanisms by which Sinularin induced cell apoptosis and Sinularin may be applied as a therapeutic agent for human prostate cancer. [ABSTRACT FROM AUTHOR]

A catalyst‐ and metal‐free electrochemical hydrodehalogenation of aryl halides is disclosed. Our reaction by a flexible protocol is operated in an undivided cell equipped with an inexpensive graphite rod anode and cathode. Trialkylamines nBu3N/Et3N behave as effective reductants and hydrogen atom donors for this electrochemical reductive reaction. Various aryl and heteroaryl bromides worked effectively. The typically less reactive aryl chlorides and fluorides can also be smoothly converted. The utility of our method is demonstrated by detoxification of harmful pesticides and hydrodebromination of a dibrominated biphenyl (analogues of flame‐retardants) in gram scale. [ABSTRACT FROM AUTHOR]

Small-cell lung cancer (SCLC) is a highly malignant type of lung cancer with no effective second-line chemotherapy drugs. Arsenic trioxide (As2O3) was reported to exert antiangiogenesis activities against lung cancer and induce poor development of vessel structures, similar to the effect observed following the blockade of Notch signaling. However, there are no direct evidences on the inhibitory effects of As2O3 on tumor growth and angiogenesis via blockade of Notch signaling in SCLC. Here, we found that As2O3 significantly inhibited the tumor growth and angiogenesis in SCLC and reduced the microvessel density. As2O3 disturbed the morphological development of tumor vessels and downregulated the protein levels of delta-like canonical Notch ligand 4 (Dll4), Notch1, and Hes1 in vivo. DAPT, a Notch signaling inhibitor, exerted similar effects in SCLC. We found that both As2O3 treatment and Notch1 expression knockdown resulted in the interruption of tube formation by human umbilical vein endothelial cells (HUVECs) on Matrigel. As2O3 had no effects on Dll4 level in HUVECs but significantly inhibited the expression of Notch1 and its downstream gene Hes1 regardless of Dll4 overexpression or Notch1 knockdown. These findings suggest that the antitumor activity of As2O3 in SCLC was mediated via its antiangiogenic effect through the blockade of Notch signaling, probably owing to Notch1 targeting. [ABSTRACT FROM AUTHOR]

Highlights • A supersaturated boundary layer formed when PS-PVD jet interacted with substrate. • The boundary layer satisfies the thermodynamic condition of cluster's formation. • The boundary layer controlled by changing the spray distance and powder feed rate. Abstract Plasma spray-physical vapor deposition (PS-PVD) is used to produce columnar microstructure coatings for vapor materials under particular operating parameters. However, due to the particular conditions of PS-PVD, the state of vapor material transported in plasma jet is difficult to predict by experimental method. Moreover, the properties of plasma jet changes sharply when the hot plasma jet approaches a relatively low temperature substrate. It is more difficult to examine the behavior variation of vapor material by experiment. In this work, the thermodynamic condition for state variation of the vapor material along with methods to change this condition were studied. The distribution of plasma temperature near the substrate surface was obtained through simulation and the vapor pressure of vapor materials was calculated by the obtained temperature distribution. The supersaturated boundary layer was obtained from the distribution of the vapor pressure and partial pressure of the vapor atoms. The environment of this supersaturated boundary layer agreed with the thermodynamic conditions of the state variation of vapor materials. Further, this layer could be varied by changing the spraying distance and powder feed rate, thus allowing further control of the state variation of vapor materials. For PS-PVD process, especially for the deposition of columnar coating, it is very important to understand the properties of boundary layer and condensation conditions of vapor materials; this study provides the basis for future research on the transport of materials in the boundary layer. [ABSTRACT FROM AUTHOR]

A lot of work has been done for the effects evaluation of electronic equipment due to high-power electromagnetic environments. The focus of the evaluation usually stays on whether the effects occur or not (“1” or “0”) during tests. However, in addition to such kind of either-or effects, multilevel effects happen in many practical cases as well. In this paper, we propose a kind of statistical approach for the evaluation of multilevel effects. By means of multinomial regression, the occurrence probabilities of each level of effects can be estimated simultaneously. Through maximum likelihood estimation (MLE), both the Softmax model and the mutually independent normal distribution assumption model are built and solved in a numerical way. We also talk about how the data affect the goodness of the regression. As a consequence, the Monte Carlo simulation gives a quasi-function relationship about model stability and estimation error. A case study on computer communication system has been conducted in the laboratory to assess the validity and applicability of the proposed models. The result is satisfactory for the three-level cases and gives all the probability prediction of the malfunction occurrences. [ABSTRACT FROM AUTHOR]

Stroke, the second-largest cause of death and the leading cause of disability globally, presents significant challenges in terms of prognosis and treatment. Identifying reliable prognosis biomarkers and treatment targets is crucial to address these challenges. Circular RNA (circRNA) has emerged as a promising research biomarkers and therapeutic targets because of its tissue specificity and conservation. However, the potential role of circRNA in stroke prognosis and treatment remains largely unexplored. This review briefly elucidate the mechanism underlying circRNA's involvement in stroke pathophysiology. Additionally, this review summarizes the impact of circRNA on different forms of strokes, including ischemic stroke and hemorrhagic stroke. And, this article discusses the positive effects of circRNA on promoting cerebrovascular repair and regeneration, maintaining the integrity of the blood-brain barrier (BBB), and reducing neuronal injury and immune inflammatory response. In conclusion, the significance of circRNA as a potential prognostic biomarker and a viable therapeutic target was underscored. [ABSTRACT FROM AUTHOR]

The static dipole polarizabilities of the 1 1S ∼ 51S, 23S ∼ 63S states of helium are presented. Our results are accurate up to at least eight digits. The majority of ∞ He (infinite mass helium) data are better than the data derived by Yan with Hylleraas coordinates, 1 3 and close to the newest results achieved by another method. 1 8 We demonstrate the results of 4He besides. [ABSTRACT FROM AUTHOR]

Arsenic trioxide (As2O3) exhibits a remarkable effect on leukemia treatment; however, its effect on solid tumors remains poorly explored. The present study demonstrated the inhibitory effect of As2O3 on lung cancer and explored its possible mechanism. It was observed that As2O3 significantly inhibited the growth of lung cancer xenografts and tumor angiogenesis in vivo. The inhibitory effect of As2O3 on cell proliferation in vitro was more remarkable in vascular endothelial cells than in lung cancer cells. It was also observed that As2O3 inhibited the migration of vascular endothelial cells and disrupted vascular tube formation on Matrigel assays. In addition, a series of key signaling factors involved in multiple stages of angiogenesis, including matrix metalloproteinase (MMP)‑2, MMP‑9, platelet‑derived growth factor (PDGF)‑BB/PDGF receptor‑β, vascular endothelial growth factor (VEGF)‑A/VEGF receptor‑2, basic fibroblast growth factor (FGF)/FGF receptor‑1 and delta like canonical Notch ligand 4/Notch‑1, were regulated by As2O3. These findings suggested that anti‑angiogenesis may be an underlying mechanism of As2O3 anticancer activity in lung cancer. [ABSTRACT FROM AUTHOR]

A new polynuclear Cu(II) compound, [Cu 4 (bpy) 4 (OH) 4 (H 2 O)(BTC)]NO 3 ·8H 2 O ( 1 ), was prepared by self-assembly from the solution of copper(II) nitrate and two kinds of ligands, 2,2′-bipyridine (bpy) and benzene-tricarboxylic acid (H 3 BTC). Single crystal structure analysis reveals that 1 features a rare asymmetric chair-like hydroxyl-bridged tetra-copper cluster: [Cu 4 (OH) 4 ] core along with one H 2 O and one BTC 3− occupied each terminal coordinated site. In addition, the magnetic property has been investigated. [ABSTRACT FROM AUTHOR]

To reveal the structure-function relationship of heme proteins, and to provide clues for creating artificial heme proteins with improved functions, we here use myoglobin (Mb) as a model protein, and report that its peroxidase activity can be enhanced by construction of two distal histidines and a channel to the heme pocket. It showed that in addition to a single distal histidine with a suitable distance to the heme iron (Phe43 to His43 mutation), a second distal histidine (Leu29 to His29 mutation) can work cooperatively to increase the turnover number, mimicking the role of well-known His-Arg pair in native peroxidases. Moreover, a channel created to the heme pocket by removal of the native His64 gate (His64 to Ala64 mutation) was shown to facilitate the binding of substrate, resulting in enhanced catalytic efficiency for the triple mutant L29H/F43H/H64A Mb, which is beyond the addition of both double mutants, L29H/H64A Mb and F43H/H64A Mb. These results provide valuable information for elucidating the structure-function relationship of heme proteins. In addition, this study provides clues for design of artificial heme proteins, and the strategy of creating a channel to the heme active center is expected be extended to design of other artificial enzymes with improved catalytic performance. [ABSTRACT FROM AUTHOR]

Purpose: To elucidate the role of tumor-associated macrophage (TAM) in the loss of ERα in endometrial cancer (EC) and the underlying mechanism.Materials and Methods: Tissue microarrays and immunohistochemistry assays were performed using endometrial cancer tissue along with coculture, immunofluorescence, invasion assays and ChIP-qPCR using a human endometrial cancer cell line.Results: Compared with normal tissue, an increased number of TAM was found in EC tissue (34.0 ± 2.6 vs. 8.3 ± 1.1, respectively; p < 0.001), which may downregulate ERα (27.4%, p < 0.05 for HEC-1A and 16.9%, p < 0.05 for Ishikawa) and promote EC cell invasion (1.8-fold, p < 0.001 for HEC-1A and 2.0-fold, p < 0.001 for Ishikawa). Furthermore, we found that TAM-derived CXCL8 mediated the loss of ERα and cancer invasion via HOXB13. HOXB13 was highly expressed in the ERα-negative subtype (r = -0.204, p = 0.002) and low expression of ESR1 was associated with a poor prognosis for EC patients (log-rank p < 0.05).Conclusion: TAM-secreted CXCL8 downregulated the ERα expression of EC cells via HOXB13, which may be associated with cancer invasion, metastasis and poor prognosis. [ABSTRACT FROM AUTHOR]

We propose a new algorithm to extend the standard Fibonacci photon sieve to the phase-only generalized Fibonacci photon sieve (GFiPS) and find that the focusing properties of the phase-only GFiPS are only relevant to the characteristic roots of the recursion relation of the generalized Fibonacci sequences. By switching the transparent and opaque zones on the basis of the generalized Fibonacci sequences, we not only realize adjustable bifocal lengths, but also give their corresponding analytic expressions. Besides, we investigate a special phase-only GFiPS, a spiral-phase GFiPS, which can present twin vortices along the axial coordinate. Compared with the single focusing system, bifocal system can be exploited to enhance the processing speed, and offer a broad range of applications, such as direct laser writing, optical tweezers or atom trapping and paralleled fluorescence microscope. [ABSTRACT FROM AUTHOR]

Heme proteins perform diverse biological functions, of which myoglobin (Mb) is a representative protein. In this study, the O 2 carrier Mb was shown to cleave double stranded DNA upon aerobic dithiothreitol-induced reduction, which is fine-tuned by an additional distal histidine, His29 or His43, engineered in the heme active center. Spectroscopic (UV–vis and EPR) and inhibition studies suggested that free radicals including singlet oxygen and hydroxyl radical are responsible for efficient DNA cleavage via an oxidative cleavage mechanism. On the other hand, L29E Mb, with a distinct heme active center involving three water molecules in the met form, was found to exhibit an excellent DNA cleavage activity that was not depending on O 2 . Inhibition and ligation studies demonstrated for the first time that L29E Mb cleaves double stranded DNA into both the nicked circular and linear forms via a hydrolytic cleavage mechanism, which resembles native endonucleases. This study provides valuable insights into the distinct mechanisms for DNA cleavage by heme proteins, and lays down a base for creating artificial DNA endonucleases by rational design of heme proteins. Moreover, this study suggests that the diverse functions of heme proteins can be fine-tuned by rational design of the heme active center with a hydrogen-bonding network. [ABSTRACT FROM AUTHOR]

The selective radical/radical cross-coupling of two different organic radicals is a great challenge due to the inherent activity of radicals. In this paper, a copper-catalyzed radical/radical C [ABSTRACT FROM AUTHOR]

The selective radical/radical cross-coupling of two different organic radicals is a great challenge due to the inherent activity of radicals. In this paper, a copper-catalyzed radical/radical C [ABSTRACT FROM AUTHOR]

Transcription factors play an important role in the pathophysiology of many neurological disorders, including stroke. In the past three decades, an increasing number of transcription factors and their related gene signaling networks have been identified, and have become a research focus in the stroke field. Krüppel-like factors (KLFs) are members of the zinc finger family of transcription factors with diverse regulatory functions in cell growth, differentiation, proliferation, migration, apoptosis, metabolism, and inflammation. KLFs are also abundantly expressed in the brain where they serve as critical regulators of neuronal development and regeneration to maintain normal brain function. Dysregulation of KLFs has been linked to various neurological disorders. Recently, there is emerging evidence that suggests KLFs have an important role in the pathogenesis of stroke and provide endogenous vaso-or neuro-protection in the brain's response to ischemic stimuli. In this review, we summarize the basic knowledge and advancement of these transcriptional mediators in the central nervous system, highlighting the novel roles of KLFs in stroke. [ABSTRACT FROM AUTHOR]

Cerebral vascular endothelial cells form the major element of the blood–brain barrier (BBB) and constitute the primary interface between circulating blood and brain parenchyma. The structural and functional changes in cerebral endothelium during cerebral ischemia are well known to result in BBB disruption, vascular inflammation, edema, and angiogenesis. These complex pathological processes directly contribute to brain infarction, neurological deficits, and post-stroke neurovascular remodeling. Ischemic endothelial dysfunction appears to be tightly controlled by multiple gene signaling networks. Non-coding RNAs (ncRNAs) are functional RNA molecules that are generally not translated into proteins but can actively regulate the expression and function of many thousands of protein-coding genes by different mechanisms. Various classes of ncRNAs, including microRNAs (miRNAs), long non-coding RNAs (lncRNAs), small nucleolar RNAs (snoRNAs) and piwi-interacting RNAs (piRNAs), are highly expressed in the cerebrovascular endothelium where they serve as critical mediators to maintain normal cerebral vascular functions. Dysregulation of ncRNA activities has been closely linked to the pathophysiology of cerebral vascular endothelium and neurologic functional disorders in the brain’s response to ischemic stimuli. In this review, we summarize recent advancements of these ncRNA mediators in the brain vasculature, highlighting the specific roles of endothelial miRNAs in stroke. [ABSTRACT FROM AUTHOR]

In order to improve the efficiency of solar street lamp system, the maximum power point tracking (MPPT) method was applied to its controller. After the analysis of MPPT principle, specific methods to implement MPPT and drive Buck circuit were proposed. Also, by using AVR Studio program and Multisim and Proteus as the platform, a control system based on ATmega16 was finally built. On the basis of a simulation test that was passed, the experiment was conducted. The results show that the duty cycle of PWM waves is in accordance with the empirical value, which indicates that the solar panel charges the storage battery with maximum power, and the controller charges and discharges the battery in a scientific way. [ABSTRACT FROM AUTHOR]

Excited-statedynamics in α-perylene single crystals is studiedby time-resolved fluorescence and transient absorption techniquesunder different excitation conditions. The ultrafast lifetimes ofthe “hot” excimer (Y) state were resolved. Three competingexcited-states decay channels are observed: excimer formation, dimercation generation, and singlet fission. The singlet fission inducedby two-photon and consecutive two-quantum absorption is reported forthe first time in an α-perylene crystal. [ABSTRACT FROM AUTHOR]

Highlights: [•] L29H Mb in DDAB film on electrode oxidizes guaiacol using O2 as an oxidant. [•] L29H Mb has a ∼3.6-fold higher reactivity than that of Mb at pH 7.0. [•] Distal histidines in L29H Mb play a key role in activation of O2 by providing protons. [ABSTRACT FROM AUTHOR]

A formal synthesis of aspidospermidine is reported through a novel preparation of Stork's penultimate tricyclic ketone intermediate. The key steps of the synthesis consist of an intramolecular cascade transannular cyclization, triggered by the removal of Boc group, which simultaneously forms the C, D, and E rings of aspidospermidine and conveniently setting up the quaternary stereo-center via decarboxylative alkylation reaction of the β-keto ester. [ABSTRACT FROM AUTHOR]

Lithiation-induced plasticity is a key factor that enables Si electrodes to maintain long cycle life in Li-ion batteries. We study the plasticity of various lithiated silicon phases based on first-principles calculations and identify the linear dependence of the equivalent yield stress on the hydrostatic pressure. Such dependence may cause the compression-tension asymmetry in an amorphous Si thin film electrode from a lithiation to delithiation cycle, and leads to subsequent ratcheting of the electrode after cyclic lithiation. We propose a yield criterion of amorphous lithiated silicon that includes the effects of the hydrostatic stress and the lithiation reaction. We further examine the microscopic mechanism of deformation in lithiated silicon under mechanical load, which is attributed to the flow-defects mediated local bond switching and cavitation. Hydrostatic compression confines the flow defects thus effectively strengthens the amorphous structure, and vice versa. [ABSTRACT FROM AUTHOR]

Peroxisome proliferator-activated receptor gamma (PPARγ) is emerging as a major regulator in neurological diseases. However, the role of (PPARγ) and its co-regulators in cerebrovascular endothelial dysfunction after stroke is unclear. Here, we have demonstrated that (PPARγ) activation by pioglitazone significantly inhibited both oxygen–glucose deprivation-induced cerebral vascular endothelial cell death and middle cerebral artery occlusion-triggered cerebrovascular damage. Consistent with this finding, selective (PPARγ) genetic deletion in vascular endothelial cells resulted in increased cerebrovascular permeability and brain infarction in mice after focal ischaemia. Moreover, we screened for (PPARγ) co-regulators using a genome-wide and high-throughput co-activation system and revealed KLF11 as a novel (PPARγ) co-regulator, which interacted with (PPARγ) and regulated its function in mouse cerebral vascular endothelial cell cultures. Interestingly, KLF11 was also found as a direct transcriptional target of (PPARγ). Furthermore, KLF11 genetic deficiency effectively abolished pioglitazone cytoprotection in mouse cerebral vascular endothelial cell cultures after oxygen–glucose deprivation, as well as pioglitazone-mediated cerebrovascular protection in a mouse middle cerebral artery occlusion model. Mechanistically, we demonstrated that KLF11 enhanced (PPARγ) transcriptional suppression of the pro-apoptotic microRNA-15a (miR-15a) gene, resulting in endothelial protection in cerebral vascular endothelial cell cultures and cerebral microvasculature after ischaemic stimuli. Taken together, our data demonstrate that recruitment of KLF11 as a novel (PPARγ) co-regulator plays a critical role in the cerebrovascular protection after ischaemic insults. It is anticipated that elucidating the coordinated actions of KLF11 and (PPARγ) will provide new insights into understanding the molecular mechanisms underlying (PPARγ) function in the cerebral vasculature and help to develop a novel therapeutic strategy for the treatment of stroke. [ABSTRACT FROM AUTHOR]

Abstract: Three new tridentate copper(II) complexes [Cu(dthp)Cl2] (1) (dthp=2,6-di(thiazol-2-yl)pyridine), [Cu(dmtp)Cl2] (2) (dmtp=2,6-di(5-methyl-4H-1,2,4-triazol-3-yl)pyridine) and [Cu(dtp)Cl2] (3) (dtp=2,6-di(4H-1,2,4-triazol-3-yl)pyridine) have been synthesized and characterized. Crystal structure of complex 1 shows that the complex existed as distorted square pyramid with five co-ordination sites occupied by the tridentate ligand and the two chlorine anions. Ethidium bromide displacement assay, viscosity measurements, circular dichroism studies and cyclic voltammetric experiments suggested that these complexes bound to DNA via an intercalative mode. Three Cu(II) complexes were found to efficiently cleave DNA in the presence of sodium ascorbate, and singlet oxygen (1O2) and hydrogen peroxide were proved to contribute to the DNA cleavage process. They exhibited anticancer activity against HeLa, Hep-G2 and BEL-7402 cell lines. Nuclear chromatin cleavage has also been observed with AO/EB staining assay and the alkaline single-cell gel electrophoresis (comet assay). The results demonstrated that three Cu(II) complexes cause DNA damage that can induce the apoptosis of BEL-7402 cells. [Copyright &y& Elsevier]

Geschwindigkeitsbestimmend: Für die Sonogashira ‐ Kupplung wird gezeigt, dass die Transmetallierung der geschwindigkeitsbestimmende Schritt ist. Die Kreuzkupplung ist ein Pd ‐ und Cu ‐ katalysierter synergistischer Prozess, der bezüglich der [Pd] ‐ und [Cu] ‐ Katalysatoren nach einer Kinetik erster Ordnung verläuft. [ABSTRACT FROM AUTHOR]

Rate‐limiting: The transmetalation step of the Sonogashira coupling reaction has been established as the rate‐limiting step. This cross‐coupling has been demonstrated to be a Pd‐catalyzed and Cu‐catalyzed synergistic process, which exhibits a first‐order kinetic dependence on both the [Pd] and [Cu] catalysts (see scheme). [ABSTRACT FROM AUTHOR]

The effects and potential mechanisms of the vascular endothelial cell (EC)-enriched microRNA-15a (miR-15a) on angiogenesis remain unclear. Here, we show a novel finding that ECselective miR-15a transgenic overexpression leads to reduced blood vessel formation and local blood flow perfusion in mouse hindlimbs at 1-3 weeks after hindlimb ischemia. Mechanistically, gain- or loss-of-miR-15a function by lentiviral infection in ECs significantly reduces or increases tube formation, cell migration, and cell differentiation, respectively. By FGF2 and VEGF 3'-UTR luciferase reporter assays, Real-time PCR, and immunoassays, we further identified that the miR-15a directly targets FGF2 and VEGF to facilitate its anti-angiogenic effects. Our data suggest that the miR-15a in ECs can significantly suppress cell-autonomous angiogenesis through direct inhibition of endogenous endothelial FGF2 and VEGF activities. Pharmacological modulation of miR-15a function may provide a new therapeutic strategy to intervene against angiogenesis in a variety of pathological conditions. [ABSTRACT FROM AUTHOR]

A new continuous flow method using attenuated total reflection infrared (ATR-IR) spectroscopy has been developed for monitoring phase transitions in multicomponent fluids at high pressures and temperatures. Our approach uses Fourier transform infrared (FT-IR) and a modified Golden Gate attenuated total reflection (ATR) cell and exploits the fact that the absorbance of a vapor is much lower than that of the corresponding liquid to monitor the phase transition between vapor and liquid. We demonstrate that this method can provide quantitative measurements on both the dew point and the bubble point. We have validated our approach using three single-component systems (EtOH, MeOH, and H2O) and a binary system of EtOH + H2O, monitoring phase transitions at temperature up to 300 °C and pressure up to 10 MPa. [ABSTRACT FROM AUTHOR]

Abstract: The Mg–12Gd–2Y–0.5Sm–0.5Sb–0.5Zr (wt.%) alloy was prepared by casting technology. The microstructure of alloy was then investigated after solution and aging treatment (i.e., T6 heat treatment). Tensile tests were performed at a crosshead speed of 1mm/min at ambient and elevated temperature atmosphere. The results show that the aged alloy was mainly composed of α-Mg matrix and dispersed long-period ordered β′ precipitates. At 250°C, the alloy has shown the superior tensile strength (i.e., 345.5MPa). The remarkable high strength of experimental alloy was mainly associated with solution strengthen of RE and precipitation strengthening of dispersive LPO structure β′ precipitates in Mg matrix. The LPO β′ precipitates provide important strengthening sources in experimental alloy, especially at elevated temperatures. [Copyright &y& Elsevier]

Abstract: Two ruthenium(II) complexes [Ru(bpy)2(bfipH)]2+ (1) and [Ru(phen)2(bfipH)]2+ (2) have been synthesized and characterized. The DNA-binding behaviors of complexes were studied by using spectroscopic and viscosity measurements. Results suggested that the two complexes bind to DNA in an intercalative mode. Complexes 1 and 2 can efficiently photocleave pBR322 DNA in vitro under irradiation, singlet oxygen (1O2) was proved to contribute to the DNA photocleavage process. Topoisomerase inhibition and DNA strand passage assay confirmed that two Ru(II) complexes acted as efficient dual inhibitors of topoisomerases I and II. In MTT cytotoxicity studies, two Ru(II) complexes exhibited antitumor activity against BEL-7402, HeLa, MCF-7 tumor cells. The AO/EB staining assay indicated that Ru(II) complexes could induce the apoptosis of HeLa cells. [Copyright &y& Elsevier]

The amplitude of nonlinear excitations in BECs with inhomogeneities is governed by a generalized variable-coefficient Korteweg-de Vries model. With symbolic computation, the Exp-function method is modified to obtain analytical nontraveling solitary-wave and periodic-wave solutions. Through the qualitative analysis and graphical illustration, the inhomogeneous propagation features of solitary waves are discussed, and some observable effects for BEC dynamic in the presence of external potentials are provided. The modified Exp-function method is also applicable to other variable-coefficient nonlinear evolution equations. [ABSTRACT FROM AUTHOR]

Cerebral vascular endothelial cell (CEC) degeneration significantly contributes to blood-brain barrier (BBB) breakdown and neuronal loss after cerebral ischemia. Recently, emerging data suggest that peroxisome proliferator-activated receptor δ(PPARδ) activation has a potential neuroprotective role in ischemic stroke. Here we report for the first time that PPARδ is significantly reduced in oxygen-glucose deprivation (OGD)-induced mouse CEC death. Interestingly, PPARδ overexpression can suppress OGD-induced caspase-3 activity, Golgi fragmentation, and CEC death through an increase of bcl-2 protein levels without change of bcl-2 mRNA levels. To explore the molecular mechanisms, we have identified that upregulation of PPARδ can alleviate ODG-activated microRNA-15a (miR-15a) expression in CECs. Moreover, we have demonstrated that bcl-2 is a translationally repressed target of miR-15a. Intriguingly, gain- or loss-of-miR-15a function can significantly reduce or increase OGD-induced CEC death, respectively. Furthermore, we have identified that miR-15a is a transcriptional target of PPARδ. Consistent with the in vitro findings, we found that intracerebroventricular infusion of a specific PPARδ agonist, GW 501516 (2-[2-methyl-4-[[4-methyl-2-[4-(trifluoromethyl)phenyl]-1,3-thiazol-5-yl]methylsulfanyl]phenoxy]acetic acid), significantly reduced ischemia-induced miR-15a expression, increased bcl-2 protein levels, and attenuated caspase-3 activity and subsequent DNA fragmentation in isolated cerebral microvessels, leading to decreased BBB disruption and reduced cerebral infarction in mice after transient focal cerebral ischemia. Together, these results suggest that PPARδ plays a vascular-protective role in ischemia-like insults via transcriptional repression of miR-15a, resulting in subsequent release of its posttranscriptional inhibition of bcl-2. Thus, regulation of PPARδ-mediated miR-15a inhibition of bcl-2 could provide a novel therapeutic strategy for the treatment of stroke-related vascular dysfunction. [ABSTRACT FROM AUTHOR]

Abstract: Dysfunction of the microRNA (miR) network has been emerging as a major regulator in neurological diseases. However, little is known about the functional significance of unique miRs in ischemic brain damage. Here, we found that miR-497 is induced in mouse brain after transient middle cerebral artery occlusion (MCAO) and mouse N2A neuroblastoma (N2A) cells after oxygen-glucose deprivation (OGD). Loss-of-miR-497 function significantly suppresses OGD-induced N2A cell death, whereas gain-of-miR-497 function aggravates OGD-induced neuronal loss. Moreover, miR-497 directly binds to the predicted 3′-UTR target sites of bcl-2/-w genes. Furthermore, knockdown of cerebral miR-497 effectively enhances bcl-2/-w protein levels in the ischemic region, attenuates ischemic brain infarction, and improves neurological outcomes in mice after focal cerebral ischemia. Taken together, our data suggest that miR-497 promotes ischemic neuronal death by negatively regulating antiapoptotic proteins, bcl-2 and bcl-w. We raise the possibility that this pathway may contribute to the pathogenesis of the ischemic brain injury in stroke. [Copyright &y& Elsevier]