Search

Exploring a two-dimensional ferromagnetic material with a high Curie temperature and large magnetic anisotropy energy is still challenging. Here, we implement an effective adjustment on the electronic and magnetic properties of VI3 monolayer by means of first-principles calculation. The results indicate that the most stable structure of VI3 monolayer is particularly susceptible to the calculation parameter such as Hubbard U and the spin-orbit coupling (SOC). Ultimately, under density functional theory (DFT) +U + SOC (U = 3 eV), the most stable structure of VI3 monolayer is a ferromagnetic semiconductor with a direct band gap of 0.51 eV, and the predicted Curie temperature (TC) is 29 K. Biaxial strain and carrier doping could not only induce VI3 monolayer FM-AFM-FM transition, but also effectively increase TC to 123 K under 0.5 electron doping. Meanwhile, carrier hoping realizes the potential ferromagnetic half-metal. Fortunately, in the constructing alloy monolayer, the VTaI6 monolayer is found a ferromagnetic half-metal under DFT + U (U = 3, 1 eV for V and Ta), and the TC is increased to 74 K. Moreover, VTaI6 monolayer possesses a large in-plane magnetic anisotropy energy (IMA) and its physical origin is explained in detail based on the second-order perturbation theory. These findings suggest that VI3 monolayer has a potential application in the spintronics and high-density magnetic storage devices.

Three new isobenzofuranone derivatives erinaceolactones D-F (1-3), together with four known ones (4-7), were isolated from the fruiting bodies of Hericium erinaceus. Their structures were determined on the basis of comprehensive spectroscopic analyses including UV, 1D, 2D NMR and HR-TOF-MS. The absolute configuration of erinaceolactone D (1) and erinaceolactone E (2) were assigned by comparing their specific rotation with those of analogs in literatures. The four known compounds were isomers with each other and were isolated simultaneously for the first time.

Based on the ansys finite element method, the ring’s strain of a high precision angle sensor was analysed. The method which translates the rotation of the sensor ring into the rotation of the direction of gravity in ansys was used, and the rotation of the gravity direction was translated into the trigonometric function decomposition of gravity acceleration on the X axis and Z axis directions. The strain was measured at every degree from 0 to 90, and finally the curve graph between angle and strain was draw using matlab software.

Twenty new acyl thiourea derivatives of podophyllotoxin and 4′-demethylepipodophyllotoxin were prepared and screened for their cytotoxicity against four human tumor cell lines, A-549, DU-145, KB, and KBvin. With IC 50 values of 0.098–1.13 μM, compounds 13b , 13c , and 13o displayed much better cytotoxic activity than the control etoposide. Most importantly, 13b and 13o exhibited promising cytotoxicity against the drug resistant tumor cell line KBvin with IC 50 values of 0.098 and 0.13 μM, respectively, while etoposide lost activity completely. Structure–activity relationship (SAR) correlations of the new derivatives have been established. Compounds 13b and 13o merit further development as a new generation of epipodophyllotoxin-derived antitumor clinical trial candidates.

Hericium erinaceus is a well-known medicinal and edible mushroom, which is considered as a potential source to obtain antitumor candidates. In this work, five new isoindolinones, named erinaceolactams A-E (1-5), along with five known compounds (6-10), were isolated from 70% ethanol extract of the fruiting bodies of H. erinaceus. The structures of new compounds were validated by HRESIMS and 1D, 2D NMR. It's worth mentioning that there are two pairs of isomers included in the new compounds. Moreover, their cytotoxicity against metastatic human hepatocellular carcinoma cell lines SMMC-7221 and MHCC-97H were evaluated. The results showed that compounds 6 and 7 exhibited promising inhibitory potency against the growth of two cell lines.

Polyamidoamine (PAMAM) dendrimer represents one of the most efficient polymeric gene carriers. To investigate the effect of the core structure and generation of dendrimers on the complex formation and transfection efficiency, a series of PAMAM dendrimers with a trimesyl core (DT) at different generations (DT4 to DT8) were developed as gene carriers and compared with the PAMAM dendrimers derived from pentaerythritol (DP) and inositol (DI). The minimal generation number of DTs at which the dendrimer has enough amino group density to effectively condense DNA was higher (generation 6) than those of DPs and DIs (generation 5). DTs of generation 6 or higher condensed DNA into complexes with an average diameter ranging from 100 to 300 nm, but the 4th and 5th generations of DT (DT4 and DT5) formed only a severe aggregate with DNA. Interestingly, the DT6/pDNA complex was determined to be much smaller (100-300 nm) than those prepared with DP5 or DI5 (>600 nm) at N/P ratios higher than 15. The optimal generation numbers at which the dendrimers showed the highest transgene expression in COS-7 cells were 5 for DPs and DIs but 6 for DTs. The DT6/pDNAcomplex with smaller size mediated higher transgene expression in COS-7 cells than those prepared with DP5 or DI5. The in vitro transfection efficiency of the DT dendrimers as evaluated in HeLa cells, COS-7 cells, and primary hepatocytes decreased in the order of DT6 > DT7 > DT8 > DT5 > DT4. The transfection mediated by DT6 was significantly inhibited by bafilomycin A1. The acid-base titration curve for DT6 showed high buffer capacity in the pH range from 5.5 to 6.4 (pK(a) approximately 6). This permits dendrimers to buffer the pH change in the endosomal compartment. However, the transfection efficiency mediated by DT6 decreased significantly in the presence of serum in both HeLa cells and COS-7 cells. The cytotoxicity of DTs evaluated in HeLa cells using the 3-{4,5-dimethylthiazol-2-yl}-2,5-diphenyltetrazolium bromide assay showed a trend of increasing toxicity with the polymer generations. The LD50 values of DT4 through DT8 were 628, 236, 79, 82, and 77 microg/mL, respectively, which were higher than that of poly(ethyleneimide) (18 microg/mL) and poly(L-lysine) (28 microg/mL) in the same assay. With a lower cytotoxicity and versatility for chemical conjugation, these PAMAM dendrimers with a DT core warrant further investigation for nonviral gene delivery.

Di(4-formyl-2-methoxyphenyl)phosphates (DFMPP) were synthesized by the condensation of vanillin with phosphoryldichlorides. The di(4-hydroxymethyl-2-ethoxyphenyl)phosphates (DHMPP) were prepared by the reduction of DFMPP with potassium borohydride. The 31P-1H coupling in DFMPP (compounds 1a-h) was investigated and the splitting of the 31P signal by the 1H nuclei was observed only with the alkyl DFMPP (1a-e). In the non-decoupled 31P spectra a quartet at −11.3 ppm was seen for la (P-OCH 3) with JPH=11.4 Hz, and a triplet for 1b, 1c, 1d and 1e respectively (1b, P-OCH 2 δ= - 12.3 ppm, JPH=8.4 Hz; 1c, P-OCH 2CH2CH3, δ= - 12.6 ppm, JPH=7.1 Hz; 1d, P-OCH 2CH2CH2CH3, δ= - 12.9 ppm, JPH=8.4 Hz and le, P-OCH 2CH2Cl, δ= - 13.0 ppm, JPH = 8.1 Hz).

To explore the apoptosis and its mechanisms of spleen CD4⁺ CD25⁺ regulatory T (Treg) cells in severe aplastic anemia (SAA) mouse model induced by interferon (IFN-γ) in combination with busulphan (BU).The BALB/c female mice SAA model was induced by intraperitoneal injection with IFN-γ and intragastric administration with BU (combined group, n=16), with BU group (n=16), IFN-γ group (n=16) and normal group (n=16) as controls. Spleen Treg cells were purified by using of immunomagnetic beads. Apoptosis was detected by flow cytometry. AKt and TGF-β expression was measured by Western blot.Apoptosis of spleen Treg cells in combined group [(33.21±0.65)%] was significantly higher than that in BU group [(21.58±0.64)%], IFN-γ group [(17.62±1.05)%], and control[(27.38±1.89)%] (P0.05). A significantly lower expression of AKt and TGF-β protein was also seen in combined group (0.30±0.05 and 0.17±0.05), as compared to the other three groups (P0.05).Excessive apoptosis of Treg cells was found in SAA mouse model, which may be a cause of Treg cells decrease in patients with AA. The down-regulated expression of AKt and TGF-β could play a role in increased apoptosis of Treg cells. Our data may provide a new treatment strategy in AA.

WT1 (Wilms' tumor gene 1) overexpression is implicated in the prognosis of acute leukemia. The purpose of this study was to investigate WT1 expression and its clinical implication in childhood acute leukemia (AL) in Chinese population. Bone marrow specimen from 200 children at different stages of acute leukemia and from 21 children without leukemia were studied. The WT1 expression at diagnostic marrow specimen in both acute myeloid leukemia (AML) and acute lymphoid leukemia (ALL) was higher than control group, whereas WT1 expression in AML was higher than in ALL, and WT1 expression level in relapse in ALL increased more significantly than in AML. The WT1 expression level showed positive correlation with the hypodiploidy and BCR-ABL fusion gene in acute leukemia. A rapidly decrease of WT1 expression level predicted a good response to the induction therapy and low expression of WT1 correlates with remission status. This study suggested that WT1 expression levels in acute leukemia can potentially be a marker for evaluating therapeutic efficacy, correlating with monitoring minimal residue disease, and predicting hematological relapse in children acute leukemia.