Search

BackgroundNecroptosis, a form of programmed cell death, is increasingly being investigated for its controversial role in tumorigenesis and progression. Necroptosis suppresses tumor formation and tumor development by killing tumor cells; however, the necrotic cells also promote tumor formation and tumor development via the immunosuppressive effect of necroptosis and inflammatory response caused by cytokine release. Thus, the exact mechanism of necroptosis in pan-cancer remains unknown.MethodsThe data of 11,057 cancer samples were downloaded from the TCGA database, along with clinical information, tumor mutation burden, and microsatellite instability information of the corresponding patients. We used the TCGA data in a pan-cancer analysis to identify differences in mRNA level as well as single nucleotide variants, copy number variants, methylation profiles, and genomic signatures of miRNA-mRNA interactions. Two drug datasets (from GDSC, CTRP) were used to evaluate drug sensitivity and resistance against necroptosis genes.ResultsNecroptosis genes were aberrantly expressed in various cancers. The frequency of necroptosis gene mutations was highest in lung squamous cell carcinoma. Furthermore, the correlation between necroptosis gene expression in the tumor microenvironment and immune cell infiltration varied for different cancers. High necroptosis gene expression was found to correlate with NK, Tfh, Th1, CD8_T, and DC cells. These can therefore be used as biomarkers to predict prognosis. By matching gene targets with drugs, we identified potential candidate drugs.ConclusionOur study showed the genomic alterations and clinical features of necroptosis genes in 33 cancers. This may help clarify the link between necroptosis and tumorigenesis. Our findings may also provide new approaches for the clinical treatment of cancer.

Polyphenols are functional compounds in plants, which possess many bioactivities beneficial for humans. The aim of this study was to establish a highly efficient method for extracting polyphenol compounds from areca seeds and further to identify polyphenols and antioxidant properties of the seeds. A quadratic general rotary unitized design was used to determine the optimal extraction process. The polyphenols were identified using LC-TOF-MS. By comparison with ascorbic acid (Vc), the antioxidant activities of the ethanol extracts were evaluated using three complementary in vitro assays: inhibition of the DPPH (1,1-diphenyl-2-picrylhydrazyl) radical-scavenging activity, hydroxyl radical-scavenging activity, and reducing ability. The two major polyphenols obtained were epicatechin and syringic acid. The ethanol extracts of areca seeds showed significantly greater antioxidant activity (p < 0.05) than Vc using the DPPH and reducing power assay, but lower ability (p < 0.05) using the hydroxyl radical assay. The results indicate that the areca seed is an excellent food material with potential antioxidant properties.

A sensitive method to determine the optic axis azimuth of the birefringence element is presented, which is based on laser feedback. The phase difference between the two intensities in birefringence feedback changes with the angle between the optic axis of the birefringence element and laser original polarization. The phase difference is highly sensitive to the relative position of the optic axis and the laser original polarization. This method is used to highly precisely determine the optic axis azimuth, and is able to distinguish between the fast axis and the slow axis of the birefringence element. Theoretical analysis and experimental results are both demonstrated. [ABSTRACT FROM AUTHOR]

The phase tuning characteristics of a double-longitudinal-mode He-Ne laser with optical feedback are demonstrated. The phase behaviors of the two adjacent longitudinal modes are studied with different laser cavity lengths at the weak feedback level, and it is found that the phase difference of the two modes can be 0 to 180&dgr; along with the changing of the length of external cavity. The high-density intensity fringes are obtained with asymmetric feedback cavity at a strong feedback level. In particular, the phase difference is also observed between the two high-density fringes of adjacent modes, which have the potential to develop a direction sensitive laser feedback interferometer with high resolution. A simple theoretical analysis is presented, which fits well with the experimental results. [ABSTRACT FROM AUTHOR]

A novel and efficient asymmetric total synthesis of (20S)-camptothecin has been accomplished in an overall yield of 12% starting from the commercially available 2-methoxynicotinic acid. The key step in the sequence is the Sharpless asymmetric dihydroxylation of a 4-(but-1-en-2-yl)pyridine derivative to establish the stereocenter of (20S)-camptothecin. [ABSTRACT FROM AUTHOR]

By employing the tensor analysis technique, we propose three schemes of controlled teleportation: series controlled, circular controlled and network controlled teleportation. We discuss the necessary and sufficient condition for realizing these schemes, in which we use a general two-qubit entangled state instead of the GHZ state as the communication channel. This enables successful implementation of teleportation without using the Hadamard operation. [ABSTRACT FROM AUTHOR]

In this study, the interfacial reactions and joint reliabilities of Sn–9Zn/Cu and Sn–9Zn–0.3Ag/Cu were investigated during isothermal aging at 150 °C for aging times of up to 1,000 h. Cu5Zn8 IMCs layer is formed at the as-soldered Sn–9Zn/Cu interface. Adding 0.3wt.% Ag results in the adsorption of AgZn3 on the Cu5Zn8 IMCs layer. The as-soldered Sn–9Zn/Cu and Sn–9Zn–0.3Ag/Cu joints have sufficient pull strength. The thickness of the IMCs layer formed at the interface of Sn–9Zn/Cu and Sn–9Zn–0.3Ag/Cu both increase with increasing aging time. Correspondingly, both the pull forces of the Sn–9Zn and Sn–9Zn–0.3Ag soldered joints gradually decrease as the aging time prolonged. However, the thickness of the IMCs layer of Sn–9Zn–0.3Ag/Cu increases much slower than that of Sn–9Zn/Cu and the pull force of Sn–9Zn–0.3Ag soldered joint decreases much slower than that of Sn–9Zn soldered joint. After aging for 1,000 h, some Cu–Sn IMCs form between the Cu5Zn8 IMC and the Cu substrate, many voids form at the interface between the Cu5Zn8 layer and solder alloy, and some cracks form in the Cu5Zn8 IMCs layer of Sn–9Zn/Cu. The pull force Sn–9Zn soldered joint decreases by 53.1% compared to the pull force measured after as-soldered. Fracture of Sn–9Zn/Cu occurred on the IMCs layer on the whole and the fracture micrograph implies a brittle fracture. While the pull force of Sn–9Zn–0.3Ag soldered joint decreases by 51.7% after aging at 150 °C for 1,000 h. The fracture mode of Sn–9Zn–0.3Ag soldered joint is partially brittle at the IMCs layer, and partially ductile at the outer ring of the solder. [ABSTRACT FROM AUTHOR]

The microstructures, wettabilities and mechanical properties of Sn–9Zn–xAg ( x = 0, 0.1, 0.3, 0.5, 1 wt%) lead-free solders were investigated, respectively in this paper. Results show that, when the quantity of Ag added to the solder is 0.3 wt%, the microstructure of the solder becomes finer and more uniform than Sn–9Zn, and when the quantity of Ag is exceeded 0.3 wt% (upto 0.5–1 wt%), the AgZn3 intermetallic compounds appear in the solder. In particular, adding 0.3 wt% Ag improves the wettability due to the better oxidation resistance of the Sn–9Zn–0.3Ag solder. Results also indicate that adding 0.3 wt% Ag to the solder enhances mechanical property of soldered joint, at which the fracture micrographs show that plenty of small and uniform dimples could be observed on the Sn–9Zn–0.3Ag soldered joints fractures. When the content of Ag is upto 1 wt%, some Cu–Zn and Ag–Zn intermetallic compounds appear on the bottom of dimples, and the mechanical property of the soldered joint decreases. [ABSTRACT FROM AUTHOR]

The article offers information on the synthesis of 2-amino-5-hydroxypropiophenone. It states that 2-amino-5-hydroxypropiophenone was needed as a key intermediate for the construction of the AB ring with (4'S)-tricyclic hydroxylactone 3. It mentions that hydrogenation of six in the presence of a catalytic amount of 10 percent Pd-C at room temperature for 3.5 gave amine seven as a pure yellow solid in a nearly quantitative yield. Thus, a facile and practical process for the preparation of two has been developed in an overall yield of 67 percent starting from 5-hydroxy-2-nitrobenzaldehyde four.