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[en] Zrt-Irt-like protein 4 (ZIP4) is critical molecule for proper mammalian development and releasing zinc from vesicular compartments. Recent studies suggested that ZIP4 plays an important role of tumor progression in pancreatic, prostate, and hepatocellular cancers, however, little is known about the detail mechanism of ZIP4 in their cancers. In the present study, we examined the possibility of ZIP4 as a new molecular target for oral squamous cell carcinoma (OSCC). We evaluated ZIP4 expression in OSCC-derived cell lines and primary OSCC samples by quantitative RT-PCR, immunoblotting, and immunohistochemistry (IHC). We also analyzed the clinical correlation between ZIP4 status and clinical behaviors in patients with OSCC. In addition, ZIP4 knockdown cells (shZIP4 cells) and ZnCl2 treatment were used for functional experiments, including cellular proliferation assay, zinc uptake assay, and cell-cycle analysis. ZIP4 mRNA and protein were up-regulated significantly in OSCCs compared with normal counterparts in vitro and in vivo. IHC showed that ZIP4 expression in the primary OSCC was positively correlated with primary tumoral size. The shZIP4 cells showed decrease accumulation of intercellular zinc and decreased cellular growth by cell-cycle arrest at the G1 phase, resulting from up-regulation of cyclin-dependent kinase inhibitors and down-regulation of cyclins and cyclin-dependent kinases. Since cellular growth of OSCC cells after treatment with zinc was significantly greater than control cells, we speculated that intercellular ZnCl2 accumulation is an important factor for cellular growth. Consistent with our hypothesis, not only decreased zinc uptake by ZIP4 knockdown but also chelating agent, N,N,N′,N′-tetrakis(2-pyridylmethyl) ethylenediamine (TPEN), showed inhibitory effects of cellular proliferation. Therefore, our data provide evidence for an essential role of ZIP4 and intracellular zinc for tumoral growth in OSCC, suggesting that zinc uptake might be a potential therapeutic targeting event for OSCCs. - Highlights: • ZIP4 contributes to tumor progression in OSCCs. • ZIP4 regulated the cell-cycle arrest at G1/S phase in OSCC cells. • Intercellular ZnCl2 accumulation is an important factor for cellular growth. • TPEN, a chelating agent, might be a new therapeutic tool for the patients with OSCC. • ZIP4 would be a potential therapeutic target for OSCCs.
[en] Graphical abstract: ZnF2 owns open-framework structure and its negative thermal expansion (NTE) properties have been confirmed using a first-principles calculation. According to the phonon eigenvectors and group theory analysis, the lowest frequency (48.9 cm−1, B1g mode) rigid unit mode (RUM) of ZnF6 causes a rotary coupling between two adjacent octahedrons and makes the Zn–Zn distance shorter, which is considered to be most responsible for the NTE properties of ZnF2. Highlights: ► The NTE properties of ZnF2 are confirmed using a first-principles calculation. ► Phonon mode classification and Grüneisen parameters are systematically presented. ► The rigid unit mode causes a rotary coupling and makes the Zn–Zn distance shorter. ► The optical branch with the lowest frequency is most responsible for the NTE. -- Abstract: ZnF2 is reported to exhibit negative thermal expansion (NTE) at lower temperatures very recently. In this article, we present the electronic and NTE properties of ZnF2 using a first-principles calculation. Our results show that ZnF2 is an insulator with a direct band gap and a strong hybridization occurs between Zn-3p, 4s and F-2p states. The related calculations on NTE properties are obtained within the quasi-harmonic approximation. The resulting relationship between volume and temperature confirms the NTE properties. Besides, we discuss the NTE mechanism in accordance to phonon vibrational modes. The phonon vibrational modes contributing to the NTE are singled out by Grüneisen parameters and all these modes are low-frequency optical phonons. The lowest frequency rigid unit mode (RUM) of ZnF6 causes a rotary coupling between two adjacent octahedrons and makes the Zn–Zn distance shorter, which is most responsible for the NTE properties of ZnF2.
[en] A theoretical phase diagram of [N(CD3)4]2ZnCl4 crystal is constructed in the plane of two thermodynamic-potential coefficients. The orientation of the temperature (T) and pressure (P) axes is chosen in the diagram. The first diagram is used as a basis to construct the second theoretical T-P phase diagram, expanded to the region of weak negative pressures for nondeuterated [N(CH3)4]2ZnCl4 crystal. It is suggested that this region can be observed for deuterated [N(CD3)4]2ZnCl4 crystal
[en] The article investigates the role of hydrogen atoms in solid phase reaction of synthesis of zinc iodide
[ru]Statya izuchayet rol' atomov vodoroda v tvyordofaznoy reaktsii formirovaniya iodida tsinka
[en] The throwing power of commercial acid zinc plating solutions is examined and the major factors that affect throwing power are discussed. The effect of the concentration of bath constituents on throwing power is shown in terms of conductivity and cathode efficiency. As the concentration of zinc chloride is decreased, the conductivity increases until a maximum value is reached and, upon further decrease, the value decreases very slowly. The cathode efficiency decreases with the decrease of concentration. Finally, the throwing power increases with the decrease of concentration rather slowly at first and then rapidly later, forming the plateau portion
[en] The effect of hydrostatic pressure and temperature on the velocities of longitudinal and shear ultrasonic waves propagated in (ZnCl/sub 2/)/sub x/ (P/sub 2/O/sub 5/)/sub 1-x/ glasses (x = 0.2, 0.3, 0.5) have been measured. The hydrostatic pressure derivatives (del C/sub 11/del p) and (del C/sub 44/del P) of the longitudinal (C-s 11 and shear C-s 44 elastic stiffness are negative: both longitudinal and shear acoustic mode Grueneisen parameters are small and negative: the application of hydrostatic pressure results in softening of the long wavelength acoustic mode phonon modes. (authors)
[en] Synthetic application of Silica–ZnCl2, as an efficient and eco-friendly catalyst for the synthesis of a small library of dihydropyrimidinones is described in this report. The reaction involves a one pot, multicomponent reaction of β-oxodithiocarboxylates, aldehydes, and urea under solvent-free conditions. The experimental procedure is simple, environmental benign, tolerated with many functional groups, and results in good to excellent yield of the products
[en] The influence of uniaxial stresses applied along the main crystallophysical directions of K2ZnCl4 crystals on the temperature dependences of birefringence δni and refractive indices ni of the crystals in the range of their phase transitions that includes the incommensurate phase has been studied. Both parameters, δni and ni, were found to be sensitive to the action of the uniaxial pressure. Considerable pressure-induced shifts of phase transition points toward different temperature regions at the paraphase-incommensurate and incommensurate-commensurate ferroelectric phase transitions were observed. The displacements were found to depend on the uniaxial stress direction, which can be explained by the influence of the applied pressure on the structure of K2ZnCl4 crystals.