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Bacillus anthracis lethal toxin (LT) is a determinant of lethal anthrax. Its function in myeloid cells is required for bacterial dissemination, and LT itself can directly trigger dysfunction of the cardiovascular system. The interplay between LT and the host responses is important in the pathogenesis, but our knowledge on this interplay remains limited. Tumor necrosis factor-α (TNF-α) is a pleiotropic pro-inflammatory cytokine induced by bacterial infections. Since LT accumulates and cytokines, predominantly TNF, amass during B. anthracis infection, co-treatment of TNF + LT in mice was used to mimic in vivo conditions for LT to function in inflamed hosts. Bone marrow transplantation and genetically engineered mice showed unexpectedly that the death of intestinal epithelial cells (IECs) rather than that of hematopoietic cells led to LT + TNF-induced lethality. Inhibition of p38α mitogen-activated protein kinase (MAPK) signaling by LT in IECs promoted TNF-induced apoptosis and necroptosis of IECs, leading to intestinal damage and mouse death. Consistently, p38α inhibition by LT enhanced TNF-mediated cell death in human colon epithelial HT-29 cells. As intestinal damage is one of the leading causes of lethality in anthrax patients, the IEC damage caused by LT + TNF would most likely be a mechanism underneath this clinical manifestation and could be a target for interventions. [ABSTRACT FROM AUTHOR]

In this work, a CuxS/GO composite hole transport layer is prepared on the surface of TiO2/CuInS2 photo-electrodes to modulate the charge transfer efficiency of quantum dot-sensitized solar cells. The normalized PL intensity of TiO2/CuInS2 photo-electrodes had been obviously quenched with the as-prepared CuxS/GO composite hole transport layer, which had exhibited excellent charge separation properties of the solar cells. Due to the reduce of charge recombination traps under CuxS/GO composite hole transport layer, the charge transfer efficiency of the solar cells had been effectively improved. As a result, the higher Voc, FF and Jsc value can be obtained for TiO2/CuInS2 quantum dot sensitized solar cells with this CuxS/GO composite hole transport layer, which had exhibited the photovoltaic conversion efficiency enhancement from 4.85% to 6.07%. [ABSTRACT FROM AUTHOR]

Colloidal quantum dots (QDs) have been considered as novel hole transport materials (HTMs) for perovskite solar cells (PSCs). Optimizing the surface state of QDs can provide higher current density and better stability. In this work, the original ligand (oleylamine) on the surface of Cu12Sb4S13 QDs is first replaced with trimethylammonium hydroxide and then with 3-mercaptopropionic acid through a two-step process, which exhibits better optical property and higher quality. Meanwhile, pure short chain ligand (3-mercaptopropionic acid) capped Cu12Sb4S13 QDs can provide an excellent charge transfer pathway when used as a hole transport layer of perovskite solar cells. As a result, PSCs based on the Cu12Sb4S13 QDs HTMs prepared by a two-step ligand-exchange process exhibited higher current density than devices based on spiro-OMeTAD, which enhanced the photovoltaic conversion efficiency from 14.65% to 15.43%. [ABSTRACT FROM AUTHOR]

In this study, the cardioprotective effects of nitric oxide (NO)-aspirin, the nitroderivative of aspirin, were compared with those of aspirin in an anesthetized rat model of myocardial ischemia-reperfusion. Rats were given aspirin or NO-aspirin orally for 7 consecutive days preceding 25 min of myocardial ischemia followed by 48 h of reperfusion (MI/R). Treatment groups included vehicle (Tween 80), aspirin (30 mg * [kg.sup.-1] * [day.sup.-1]), and NO-aspirin (56 mg * [kg.sup.-1] * [day.sup.-1]). NO-aspirin, compared with aspirin, displayed remarkable cardioprotection in rats subjected to MI/R as determined by the mortality rate and infarct size. Mortality rates for vehicle (n = 23), aspirin (n = 22), and NO-aspirin groups (n = 22) were 34.8, 27.3, and 18.2%, respectively. Infarct size of the vehicle group was 44.5 [+ or -] 2.7% of the left ventricle (LV). In contrast, infarct size of the LV decreased in the aspirin- and NO-aspirin-pretreated groups, 36.7 [+ or -] 1.8 and 22.9 [+ or -] 4.3%, respectively (both P < 0.05 compared with vehicle group; P < 0.05, NO-aspirin vs. aspirin). Moreover, NO-aspirin also improved ischemiareperfusion-induced myocardial contractile dysfunction on postischemic LV developed pressure. In addition, NO-aspirin downregulated inducible NO synthase (iNOS; 0.37-fold, P < 0.01) and cyclooxygenase-2 (COX-2; 0.61-fold, P < 0.05) gene expression compared with the vehicle group after 48 h of reperfusion. Treatment with [N.sup.G]-nitro-L-arginine methyl ester (L-NAME; 20 mg/kg), a nonselective NOS inhibitor, aggravated myocardial damage in terms of mortality and infarct size but attenuated effects when coadministered with NO-aspirin. L-NAME administration did not alter the increase in iNOS and COX-2 expression but did reverse the NO-aspirin-induced inhibition of expression of the two genes. The beneficial effects of NO-aspirin appeared to be derived largely from the NO moiety, which attenuated myocardial injury to limit infarct size and better recovery of LV function following ischemia and reperfusion. nitroaspirin; aspirin; cardioprotection; ischemia-reperfusion; infarct size

Quantum dot co-sensitized solar cells have charge recombination traps in the process of successive ionic layer adsorption and reaction. A two-step assembly linking process is employed for continuous CuInS2 and CdS QDs deposition to prepare CuInS2/CdS quantum dot co-sensitized (TiO2/CuInS2/CdS) photoelectrodes, which is anticipated to improve the charge transfer property of the solar cells. The better optical absorption and charge separation properties of TiO2/CuInS2/CdS photoelectrodes can be observed by this two-step assembly linking process. Meanwhile, due to the uniform deposition, non-aggregation of quantum dots and excellent connection between each quantum dot layer, the fill factor and photocurrent density of TiO2/CuInS2/CdS quantum dot-sensitized solar cells has been obviously improved by this two-step assembly linking process. With the second assembly linking instead of successive ionic layer adsorption and reaction, the TiO2/CuInS2/CdS quantum dot-sensitized solar cells have achieved a photovoltaic conversion efficiency enhancement from 4.5% to 5.97%. [ABSTRACT FROM AUTHOR]

Early diagnosis of low grade glioma has been a challenge to clinicians. Positron Emission Tomography (PET) using 18F-FDG as a radio-tracer has limited utility in this area because of the high background in normal brain tissue. Other radiotracers such as 18F-Fluorocholine (18F-FCH) could provide better contrast between tumor and normal brain tissue but with high incidence of false positives. In this study, the potential application of a dual tracer 18F-FCH/18F-FDG-PET is investigated in order to improve the sensitivity of PET imaging for low grade glioma diagnosis based on a mouse orthotopic xenograft model. BALB/c nude mice with and without orthotopic glioma xenografts from U87 MG-luc2 glioma cell line are used for the study. The animals are subjected to 18F-FCH and 18F-FDG PET imaging, and images acquired from two separate scans are superimposed for analysis. The 18F-FCH counts are subtracted from the merged images to identify the tumor. Micro-CT, bioluminescence imaging (BLI), histology and measurement of the tumor diameter are also conducted for comparison. Results show that there is a significant contrast in 18F-FCH uptake between tumor and normal brain tissue (2.65 ± 0.98), but with a high false positive rate of 28.6%. The difficulty of identifying the tumor by 18F-FDG only is also proved in this study. All the tumors can be detected based on the dual tracer technique of 18F-FCH/ 18F-FDG-PET imaging in this study, while the false-positive caused by 18F-FCH can be eliminated. Dual tracer 18F-FCH/18F-FDG PET imaging has the potential to improve the visualization of low grade glioma. 18F-FCH delineates tumor areas and the tumor can be identified by subtracting the 18F-FCH counts. The sensitivity was over 95%. Further studies are required to evaluate the possibility of applying this technique in clinical trials. [ABSTRACT FROM AUTHOR]

Radar micro-Doppler signature analysis of vibrating targets with the joint time-frequency methods can provide useful information for target detection, classification, and recognition. We employ a well-known method for nonlinear and nonstationary signals, Hilbert-Huang transform (HHT) as a new approach in micro-Doppler analysis. Simulation and experimental results show that it can achieve better performance than the traditional Cohen's class time-frequency methods. [ABSTRACT FROM AUTHOR]

Background: Periostin (POSTN) is a critical extracellular matrix protein in various tumor microenvironments. However, the function of POSTN in thyroid cancer progression remains largely unknown. Methods: Postn and Rag1 knock-out mice and orthotopic mouse models were used to determine the role of POSTN on papillary thyroid tumor progression. Immunofluorescence, cell co-culture, fluorescence in situ hybridization, chromatin immunoprecipitation assay, recombinant protein and inhibitor treatment were performed to explore the underlying mechanisms of POSTN-promoted papillary thyroid tumor growth. Results: POSTN is up-regulated in papillary thyroid tumors and negatively correlates with the overall survival of patients with thyroid cancer. Cancer-associated fibroblast (CAF)-derived POSTN promotes papillary thyroid tumor growth in vivo and in vitro . POSTN deficiency in CAFs significantly impairs CAF-promoted papillary thyroid tumor growth. POSTN promotes papillary thyroid tumor cell proliferation and IL-4 expression through integrin-FAK-STAT3 signaling. In turn, tumor cell-derived IL-4 induces the activation of CAFs and stimulates POSTN expression by activating STAT6. We reveal the crucial role of CAF-derived POSTN and tumor cell-derived IL-4 in driving the development of papillary thyroid tumors through the POSTN-integrin-FAK-STAT3-IL-4 pathway in tumor cells and IL-4-STAT6-POSTN signaling in CAFs. Conclusion: Our findings underscore the significance of POSTN and IL-4 as critical molecular mediators in the dynamic interplay between CAFs and tumor cells, ultimately supporting the growth of papillary thyroid tumors., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)