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Malignant tumors remain the health problem of highest concern among people worldwide due to its high mortality and recurrence. Lung, gastric, liver, colon, and breast cancers are among the top five malignant tumors in terms of morbidity and mortality. In cancer biology, aberrant signaling pathway regulation is a prevalent theme that drives the generation, metastasis, invasion, and other processes of all malignant tumors. The Wnt/β-catenin, PI3K/AKT/mTOR, Notch and NF-kB pathways are widely concerned and signal crosstalks exist in the five solid tumors. This review provides an innovative summary of the recent progress in research on these signaling pathways, the underlying mechanism of the molecules involved in these pathways, and the important role of some miRNAs in tumor-related signaling pathways. It also presents a brief review of the antitumor molecular drugs that target these signaling pathways. This review may provide a theoretical basis for the study of the molecular biological mechanism of malignant tumors and vital information for the development of new treatment strategies with a focus on efficacy and the reduction of side effects.

Myeloid-derived suppressor cells (MDSCs) are a heterogeneous group of cells generated in various pathologic conditions, which have been known to be key components of the tumor microenvironment (TME) involving in tumor immune tolerance. So MDSCs have been extensively researched recently. As its name suggests, immunosuppression is the widely accepted function of MDSCs. Aside from suppressing antitumor immune responses, MDSCs in the TME also stimulate tumor angiogenesis and metastasis, thereby promoting tumor growth and development. Therefore, altering the recruitment, expansion, activation, and immunosuppression of MDSCs could partially restore antitumor immunity. So, this view focused on the favorable TME conditions that promote the immunosuppressive effects of MDSCs and contribute to targeted therapies with increased precision for MDSCs.

Pose estimation with rendered key images often enables more effective and efficient performance for on-line tasks. However, it is difficult to establish correspondences between photographs and rendered images because of their different sources and features. This paper proposes SIGMA (SIFT in GMS-selected Areas), a method combining high quality detector and descriptor with effective method of removing mismatches. It preforms SIFT locally in the areas selected by GMS, which provides high precision and good distribution of points. Experiments show the precision of SIGMA is 0.7638, higher than SIFT(0.5037) and GMS(0.7206).

Heterogeneous catalytic oxidation arises from the prerequisite oxygen activation and transfer ability of metal oxide catalysts. Thus, engineering intercalated nanounits and heterophase metal oxide structures, and forming interstitial catalyst supports at the nanoscale level can drastically alter the catalytic performances of metal oxides. This is particularly important for ceria-based nanomaterial catalysts, where the interactions of reducible ceria (CeO2) and nonreducible oxides are fundamental for the preparation of enhanced catalysts for oxygen-involved reactions. Herein, we intercalated nanostructured CeO2 in the bulk phase of magnesium aluminate spinel (MgAl2O4, referred to as MgAl), produced the interstitial effect between CeO2 nanoparticles and MgAl crystallites, thus boosting their oxygen transfer and activation capability. This nanoscaled intercalation engineering significantly enhanced the number and quality of tight contact points between the nanostructured CeO2 and MgAl units. Therefore, the oxygen storage/release capability (OSC) is exceptionally improved as revealed by various characterizations and catalytic carbon oxidation reaction. A mechanism similar to the Mars–van Krevelen process at the nanoscale level was invoked to explain the catalytic oxidation mechanisms. The reactive oxygen species of gaseous O2 originate formed the bulk of the as-obtained nanomaterial, where strong interactions between the CeO2 and MgAl components occured, which were subsequently released and diffused to the catalyst-interface at elevated temperatures. Silver supported on Ce–MgAl produced an approximately 4-fold higher concentration of active oxygen species than Ag/MgAl, and gives the optimum low-temperature oxidation at 229 °C. This study verifies the importance of the redox performance of ceria-spinel with enhanced OSC, which validates that the arrangement of contacts at the nanoscale can substantially boost the catalytic reactivity without varying the microscale structure and properties of spinel.

Silver nanoparticles supported on nitrogen-doped activated carbon (Ag/AC-N) are demonstrated as promising catalysts for the chemoselective hydrogenation of dimethyl oxalate to methyl glycolate. Characteristic studies by TPR, XPS, and Raman indicate that AC-N benefits the dispersion of silver nanoparticles due to the strong electronic interactions between nitrogen and silver species. The optimized Ag/AC-N catalyst shows intensified performance in terms of high activity and excellent stability. It is inferred that the co-existence of Ag 0 and Ag + derived from the strong interactions of nitrogen with Ag species renders the superior catalytic performance of Ag/AC-N.

Heterogeneous catalytic oxidation arises from the prerequisite oxygen activation and transfer ability of metal oxide catalysts. Thus, engineering intercalated nanounits and heterophase metal oxide structures, and forming interstitial catalyst supports at the nanoscale level can drastically alter the catalytic performances of metal oxides. This is particularly important for ceria-based nanomaterial catalysts, where the interactions of reducible ceria (CeO

Mesoporous silica SBA-15-supported bimetallic silver–nickel catalysts (Ag–Ni/SBA-15) were prepared by a co-impregnation method for the chemoselective hydrogenation of dimethyl oxalate (DMO) to methyl glycolate (MG). The structure and physicochemical properties of the catalysts were characterized using N 2 adsorption–desorption, X-ray fluorescence spectroscopy, transmission electron microscopy, H 2 -temperature-programmed reduction, UV–vis light diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy, fourier-transform infrared spectroscopy and ester temperature-programed desorption. Compared with monometallic Ag or Ni catalyst, the bimetallic Ag–Ni/SBA-15 catalysts exhibited enhanced catalytic performance for the chemoselective hydrogenation of DMO to MG. The optimized Ag–Ni/SBA-15 catalyst with a Ni/Ag atomic ratio of 0.2 presented the highest MG yield and excellent catalytic stability during the hydrogenation of DMO to MG for longer than 140 h. The characterization results suggested that the Ag and Ni bimetallic nanoparticles on the catalyst surfaces likely formed a segregation structure with more Ni species in the core and more Ag in the shell, and electron transfer from Ni to Ag possibly occurred. The interactions between the Ag and Ni species generated more active/adsorption sites and prevented the transmigration of bimetallic nanoparticles during hydrogenation.

Selective hydrogenation of dimethyl oxalate (DMO) derived from syngas to ethylene glycol (EG) over copper (Cu)-based catalysts is an important transformation of modern syngas chemical industry. Methanol, as a product or a solvent, can dissociate on the Cu surfaces by forming adsorbed CO under H2 atmosphere at 473 K. A small amount of adsorbed CO accelerates Cu redox processes, thus inhibiting catalytic activity with a negative kinetic reaction order. The strong interaction between CO and Cu blocks active sites and disrupts the synergy of Cu+ and Cu0 species, which are vital in DMO hydrogenation. The Ostwald ripening of Cu crystallites is induced by CO, resulting in aggregation of Cu crystallites. The imbalance of active species and crystallite aggregation lead to deactivation of the Cu catalysts during DMO hydrogenation to EG.

Purpose We investigated the effects of therapeutic mild hypothermia on patients with severe traumatic brain injury after craniotomy (TBI). Methods Eighty patients with severe TBI after unilateral craniotomy were randomized into a therapeutic hypothermia group with the brain temperature maintained at 33°C to 35°C for 4 days, and a normothermia control group in the intensive care unit. Vital signs, intracranial pressure, serum superoxide dismutase level, Glasgow Outcome Scale scores, and complications were prospectively analyzed. Results The mean intracranial pressure values of the therapeutic hypothermia group at 24, 48, and 72 hours after injury were much lower than those of the control group (23.49 ± 2.38, 24.68 ± 1.71, and 22.51 ± 2.44 vs 25.87 ± 2.18, 25.90 ± 1.86, and 24.57 ± 3.95 mm Hg; P = .000, .000, and .003, respectively). The mean serum superoxide dismutase levels of the therapeutic hypothermia group at days 3 and 7 were much higher than those of the control group at the same time point (533.0 ± 103.4 and 600.5 ± 82.9 vs 458.7 ± 68.1 and 497.0 ± 57.3 μ g/L, respectively; P = .000). The percentage of favorable neurologic outcome 1 year after injury was 70.0% and 47.5%, respectively ( P = .041). Complications, including pulmonary infections (57.5% in the therapeutic hypothermia group vs 32.5% in the control group; P = .025) were managed without severe sequelae. Conclusions Therapeutic mild hypothermia provides a promising way in the intensive care unit for patients with severe TBI after craniotomy.

Aims: To study the effects of simvastatin on oxidative stress in rats with early stage diabetic nephropathy. Methods: 60 male Sprague-Dawley rats were divided into three groups: control group (CN), streptozotocin (STZ)-induced diabetic rats group (DM) and STZ-induced diabetic rats group treated with simvastatin (DM+S). The following parameters were measured at weeks 6 and 12 in similar rats chosen randomly from each group: body and kidney weight, 24-hour urinary albumin excretion (UAE), biochemical indexes including blood glucose (GLU), low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglycerides (TG), serum creatinine (SCr), antioxidant enzymes including superoxide dismutase (SOD), glutathione S-transferase (GST), catalase (CAT) in plasma, lipid peroxidation production as malondialdehyde in plasma (MDAp) and erythrocytes (MDAe), morphology parameters such as glomerular volume (GV) and mesangial area/total glomerular area (M/T). Results: At weeks 6 and 12, GLU and kidney weight to body weight ratio were notably increased in both of the diabetic groups compared with those in the CN group without significant differences between the two diabetic groups. There were no significant differences of SCr, LDL, HDL and TG among all groups within all the experimental time. MDAp and MDAe were significantly increased in both of the diabetic groups, especially at week 12, while SOD, GST and CAT were significantly decreased compared with those in the CN group. At week 12, GV, M/T and UAE were also increased in the two diabetic groups. However, in the DM+S group, changes of lipid peroxidation production, antioxidant enzymes, UAE and GV were less pronounced than those in the DM group. Pearson’s correlation analysis and regression analysis shown that MDAp was increased while SOD, GST and CAT in plasma were decreased with elevation of UAE, GV and M/T. Conclusion: Increased lipid peroxidation and decreased antioxidant enzymes in plasma may play a role in the progression of diabetic nephropathy. Simvastatin may ameliorate these changes to protect kidney from oxidative lesion in diabetes even in the absence of lipid abnormalities.