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OBJECTIVE: To explore the in vitro and in vivo experimental study of thioredoxin- 1(Trx1) inhibitor 1-methylpropyl 2-imidazolyl disulfide (PX-12) promoting multiple myeloma H929 cell apoptosis, investigate the relationship between the inhibitory effect of PX-12 on H929 cells and reactive oxygen species (ROS). MATERIALS AND METHODS: Inhibition of PX- 12 on H929 cells in relation to reactive oxygen species (ROS), cell cycle, and apoptosis were assessed by flow cytometry. ELISA kit, IVIS Imaging, Hematoxylin and eosin (H&E) staining and immunohistochemical staining assessment were applied to assess the anti-myeloma effect in the SCID mice model established by H929EL cells. RESULTS: PX-12 inhibited proliferation of H929 cells performed time and dose dependent style. Furthermore, it significantly induced a G2/M phase arrest of the cell cycle in H929 cells. It also increased intracellular ROS and caspase-3 activity in H929 cells indicating that cells have undergone apoptosis. There was an almost 3-5-fold decrease in tumor viability measured by the Living-Imaging system after 21 and 28 days after PX-12 injection compared with the control group. Importantly, PX-12 caused significant decrease in expression of Kappa chain in vivo assessed by immunohistochemical staining. CONCLUSIONS: The results suggest that PX- 12 may be a potential strategy for the treatment of MM, and the inhibition of TRX-1 in the treatment of myeloma deserves further research. [ABSTRACT FROM AUTHOR]

Based on Special Sensor Ultraviolet Spectrographic Imager on Defense Meteorological Satellite Program spacecraft (DMSP/SSUSI) observations in the Northern Hemisphere, a particular polar cap arc observed at ∼1,500 magnetic local time (MLT) sector was identified and was named 15MLT‐PCA. A 15MLT‐PCA model proposed for the Northern Hemisphere suggests that the 15MLT‐PCA is caused by a lobe reconnection related to the tilt angle and lobe field line twisting due to a long‐lasting positive interplanetary magnetic field (IMF) By condition. However, it is unclear if the 15MLT‐PCA can be observed in the Southern Hemisphere and how the IMF By influences its occurrence and location. Using the long‐term DMSP/SSUSI observations in the Southern Hemisphere, we confirmed that the 15MLT‐PCA could be observed in the Southern Hemisphere in summer under long‐lasting negative IMF By and predominantly positive IMF Bx. The ion energy dispersion and some other statistical properties are also investigated. Further, we showed that the IMF By has a switching effect on the occurrence of the 15MLT‐PCA using multiple cases. We found that the 15MLT‐PCA disappear as soon as the IMF By changed to an unfavorable condition, but it seems that the favorable conditions need to be maintained for ∼1 hr for the occurrence of 15MLT‐PCA. We also found that the IMF By magnitude is well correlated to the MLT location of the 15MLT‐PCA. We suggest that all the results support the 15MLT‐PCA model and imply that a magnetotail lobe reconnection should be common in the summer hemisphere because the well‐known Parker Spiral favors meeting the model's IMF requirements. Plain Language Summary: It is well known that the interplanetary magnetic field (IMF) is in a Parker Spiral pattern, so in quiet solar conditions, a stable IMF By component can often be observed around 1 AU. At the same time, the geomagnetic dipole axis tilts with the ecliptic plane at different angles under different seasons and Universal Time (UT). What the combined effect of stable IMF By and dipole tilting is is unknown. A recent model of 15MLT‐PCA (polar cap arc at ∼1,500 MLT sector) suggests that the stable IMF By and dipole tilting can lead to a particular lobe reconnection. This model may reveal an important geophysical process. However, its validation is still needed because it was proposed based on merely northern‐hemisphere observations. In this study, we carefully examined the properties of 15MLT‐PCA based on southern‐hemisphere observations. The results are well consistent with the model's predictions and thus provide support to the model. Key Points: Statistical properties of 15MLT‐PCA in the Southern Hemisphere are confirmed to be consistent with a previously proposed 15MLT‐PCA modelThe interplanetary magnetic field By shows a clear switching effect on the occurrence of 15MLT‐PCA and affects its MLT location15MLT‐PCA was not observed immediately when favorable IMF conditions appeared, but after the conditions were maintained for ∼1 hr [ABSTRACT FROM AUTHOR]

An innovative method using fluorescence resonance energy transfer was developed to investigate the thermodynamic parameters for the interaction of proteins with membranes, and to determine the dissociation constant and lipid/protein stoichiometry. The second derivative of the fluorescence quenching function was shown to eliminate interference from nonspecific binding and nonquenched residual fluorescence that are linearly dependent on the concentration of lipid.

Nanosized TiO2 has been actively developed as a low-cost and environment-friendly anode material for lithium-ion batteries (LIBs), but its poor electronic conductivity seriously restricts its practical applications. This drawback is addressed in this work by the fabrication of one-dimensional mesoporous graphene@Ag@TiO2 composite nanofibers as anode materials for high-performance LIBs. The materials were prepared via electrospinning combined with annealing treatment, and the effects of graphene addition on the microstructure and electrochemical performance of the resulting mesoporous graphene@Ag@TiO2 nanofibers were investigated in detail. Ag@TiO2 nanofibers with the optimal amount of graphene displayed a maximum initial discharge capacity of 4 9 0. 5 mAh ⋅ g − 1 at 1 0 0 mA ⋅ g − 1 and retained a discharge capacity of 2 0 9. 1 mAh ⋅ g − 1 at 1 0 0 mA ⋅ g − 1 after 100 cycles. These results reflect the excellent cycling stability of the material. The average specific discharge capacity of the nanofibers (9 7. 6 mAh ⋅ g − 1 at 1 0 0 0 mA ⋅ g − 1) was two-fold higher than that of samples without graphene, and their discharge capacity returned to 2 5 3. 8 mA ⋅ g − 1 (approximately 9 6. 2 mA ⋅ g − 1 for other nanofibers) when the current density was recovered to the initial value (4 0 mA ⋅ g − 1). Electrochemical impedance spectroscopic measurements confirmed that the conductivity of the electrode was 6. 3 × 1 0 − 1 S ⋅ cm − 1 , which is higher than that of bare mesoporous Ag@TiO2 (1. 9 9 × 1 0 − 5 S ⋅ cm − 1 ). Thus, one-dimensional mesoporous graphene@Ag@TiO2 nanofibers can be regarded as a promising anode material for LIBs. One-dimensional mesoporous graphene@Ag@TiO2 composite nanofibers as anode materials for high-performance LIBs had been successfully fabricated by electrospinning combined with annealing treatment. The suitable introduction of graphene can endow the anode material with outstanding electrochemical performance with respect to high initial discharge capacity, excellent cycling stability and superior rating capability. The one-dimensional mesoporous graphene@Ag@TiO2 nanofibers can be regarded as promising anode materials for high-performance LIBs. [ABSTRACT FROM AUTHOR]

In the present work, polycrystalline Ni45Co5-xPdxMn37In13 (x = 0, 0.5, 1, and 3) Heusler alloys were prepared. The influences of Pd substitution for Co on crystal structure, martensitic transformation (MT), and magnetic properties have been carefully investigated for these quinary alloys. The structure measurement indicates that every sample possesses L10 martensitic structure at room temperature. With increasing of Pd content, it is found that the MT region shifts towards higher temperature, but the Curie transition region of austenitic state moves to lower temperature. Owing to the fact that the MT gradually approaches Curie point, the magnetization of austenitic phase is significantly decreased, while the one of martensitic phase almost remains unchanged. In addition, the functional properties associated with the field-induced reverse MT have been also studied in Ni45Co5-xPdxMn37In13 (x = 0, 0.5, and 1) alloys. In comparison to quaternary parent alloy, both of enhanced magnetostrain (0.3%) and isothermal entropy change (25 J/kg K) are observed in quinary Ni45Co4.5Pd0.5Mn37In13 alloy under an applied magnetic field up to 3 T. The implication of such results has been discussed in detail. [ABSTRACT FROM AUTHOR]