Poly[[diaquadi-μ2-cyanido-bis­(μ2-pyrazine-2-carboxyl­ato)dicopper(I)copper(II)] dihydrate]

In the title compound, {[CuIICuI 2(C5H3N2O2)2(CN)2(H2O)2]·2H2O}n, the CuII atom lies on an inversion centre and is octa­hedrally coordinated by two N atoms and two O atoms from opposing pyrazine-2-carboxyl­ate (2-pac) ligands and two water O atoms. The CuI atom has a triangular geometry, coordinated by one N atom and one C atom from two bridging cyanide ligands, and another N atom from the 2-pac ligand. The three-dimensional structure features a succession of two-dimensional sheets containing [Cu(CN)]n chains linked by Cu(2-pac)2(H2O)2 groups. The coordinated and free water mol­ecules are involved in an extended three-dimensional hydrogen-bond network with the 2-pac ligands

Unbalanced-basis-misalignment tolerant measurement-device-independent quantum key distribution

Measurement-device-independent quantum key distribution (MDIQKD) is a revolutionary protocol since it is physically immune to all attacks on the detection side. However, the protocol still keeps the strict assumptions on the source side that the four BB84-states must be perfectly prepared to ensure security. Some protocols release part of the assumptions in the encoding system to keep the practical security, but the performance would be dramatically reduced. In this work, we present a MDIQKD protocol that requires less knowledge of encoding system to combat the troublesome modulation errors and fluctuations. We have also experimentally demonstrated the protocol. The result indicates the high-performance and good security for its practical applications. Besides, its robustness and flexibility exhibit a good value for complex scenarios such as the QKD networks.Comment: 22 pages, 9 figure

Decreased Expression of Programmed Death Ligand-L1 by Seven in Absentia Homolog 2 in Cholangiocarcinoma Enhances T-Cell–Mediated Antitumor Activity

N6-methyladenosine (m6A) has been reported as an important mechanism of post-transcriptional regulation. Programmed death ligand 1 (PD-L1) is a primary immune inhibitory molecule expressed on tumor cells that promotes immune evasion. In addition, seven in absentia homolog 2 (Siah2), a RING E3 ubiquitin ligase, has been involved in tumorigenesis and cancer progression. However, the role of m6A-METTL14-Siah2-PD-L1 axis in immunotherapy remains to be elucidated. In this study, we showed that METTL14, a component of the m6A methyltransferase complex, induced Siah2 expression in cholangiocarcinoma (CCA). METTL14 was shown to enrich m6A modifications in the 3’UTR region of the Siah2 mRNA, thereby promoting its degradation in an YTHDF2-dependent manner. Furthermore, co-immunoprecipitation experiments demonstrated that Siah2 interacted with PD-L1 by promoting its K63-linked ubiquitination. We also observed that in vitro and in vivo Siah2 knockdown inhibited T cells expansion and cytotoxicity by sustaining tumor cell PD-L1 expression. The METTL14-Siah2-PD-L1–regulating axis was further confirmed in human CCA specimens. Analysis of specimens from patients receiving anti-PD1 immunotherapy suggested that tumors with low Siah2 levels were more sensitive to anti-PD1 immunotherapy. Taken together, our results evidenced a new regulatory mechanism of Siah2 by METTL14-induced mRNA epigenetic modification and the potential role of Siah2 in cancer immunotherapy

Fusion expression and high-level preparation of a glycine-rich antibacterial peptide (SK 66 ) derived from Drosophila in Escherichia coli

SK 66, a derivative of the gene cg13551 of Drosophila containing 66 amino acid peptide with N-terminal serine and C-terminal lysine, shows high antimicrobial activities. To obtain it in large amounts, the mature DNA fragment of SK 66 was acquired from the pMD18-T-SK 66 simple vector using PCR and then inserted into the Nco I and Xho I enzyme-cutting sites of pET-32a plasmid, the recombinant vector named pET-32a-SK 66 was transformed into the competent cell E. coli BL 21. The fusion protein was expressed in soluble form under the optimized conditions at high level (more than 44% of the total proteins). Then the expressed product was purified by affinity binding chromatography with Ni-NTA, salt-out, freeze-dried. The SK 66 was cleaved from the fusion protein by enterokinase, purified by using RP-HPLC and has strong antibacterial activity

Compound non-starch polysaccharide enzymes improve growth performance, slaughter performance, immune function, and apparent utilization rate of nutrients in broiler chickens fed a low-metabolizable energy diet

This study aimed to investigate the effects of compound non-starch polysaccharide (NSP) enzymes on growth performance, slaughter performance, immune function, and apparent utilization of nutrients in broiler chickens fed a low-metabolizable energy diet. A total of 240 healthy 1-day-old AA broilers (Arbor Acres, 47.2 ± 0.31 g) were randomly divided into four treatment groups, each with six replicate groups and 10 broilers per replicate. The control group was fed a basal diet; the EL-H group was fed the basal diet supplemented with 200 mg/kg compound NSP enzyme, including β-mannanase 5,000 IU/g, β-glucanase 2000 IU/g, xylanase 10,000 IU/g, and cellulase 500 IU/g. The EL-M group was fed the basal diet with 50 kcal/kg metabolizable energy removed, supplemented with 200 mg/kg compound NSP enzyme. Finally, the EL-L group was fed the basal diet with 100 kcal/kg metabolizable energy removed, supplemented with 200 mg/kg compound NSP enzyme. The results showed that feeding with a low-metabolizable energy diet supplemented with compound NSP enzymes did not significantly affect the growth performance of broilers (p > 0.05). Compared with the control group, the abdominal fat rate of broilers in the EL-L group was significantly reduced, and that of broilers in the EL-M group was significantly increased (p < 0.05). Apparent utilization of dry matter, crude protein, and energy in the diet was lower in the control group than in the EL-L group, but significantly higher in the control group than in the EL-H group (p < 0.05). In addition, apparent utilization of crude fiber was significantly increased in the EL-H, EL-M, and EL-L groups compared with the control group (p < 0.05). In conclusion, this experiment showed that the addition of 200 mg/kg compound NSP enzyme enabled maintenance of the normal growth and development of broiler chickens fed a low-metabolizable energy diet (replacing 50–100 kcal/kg metabolizable energy). This study provides a theoretical basis for the application of the compound NSP enzyme in broiler chickens

FoxO Transcription Factor Regulate Hormone Mediated Signaling on Nymphal Diapause

Diapause is a complex physiological adaptation phenotype, and the transcription factor Forkhead-box O (FoxO) is a prime candidate for activating many of its diverse regulatory signaling pathways. Hormone signaling regulates nymphal diapause in Laodelphax striatellus. Here, the function of the FoxO gene isolated from L. striatellus was investigated. After knocking-down LsFoxO in diapausal nymphs using RNA interference, the titers of juvenile hormone III and some cold-tolerance substances decreased significantly, and the duration of the nymphal developmental period was severely shorted to 25.5 days at 20°C under short day-length (10 L:14 D). To determine how LsFoxO affects nymphal diapause, analyses of RNA-sequencing transcriptome data after treatment with LsFoxO–RNA interference was performed. The differentially expressed genes affected carbohydrate, amino acid and fatty acid metabolism, and phosphatidylinositol 3-kinase/protein kinase B signaling pathway. Thus, LsFoxO acts on L. striatellus nymphal diapause and is, therefore, a potential target gene for pest control. This study may lead to new information on the regulation of nymphal diapause in this important pest