Association between TNFα - 308 G/A polymorphism and oral lichen planus (OLP): a meta-analysis

<div><p>Abstract Objectives To determine whether Tumor Necrosis Factor alpha (TNFα) –308 G/A polymorphism is associated with oral lichen planus (OLP). Material and Methods A systematic electronic search of the literature was conducted to identify all published studies on the association between TNFα –308 G/A polymorphism and OLP. All case-control studies evaluating the TNFα –308 G/A polymorphisms in OLP were selected. A meta-analysis of the studies that fulfilled the inclusion criteria was performed. Odds ratios (OR) with 95% confidence intervals (CI) were also calculated. Results Seven studies comprising 450 OLP cases and 867 controls were included in the meta-analysis. In the pooled analysis, TNFα –308 G/A polymorphism was associated with OLP with random effects and OR of 2.33 (95%CI=1.07-5.11; p=0.03), assuming a dominant mode of inheritance (AA+GA vs. GG). In the subgroup analysis by ethnicity, TNFα –308 G/A was associated with a significantly increased odds ratio of OLP in mixed ethnicity (OR=5.22; 95%CI=1.93-14.15; p=0.001), but not in Asians (OR=1.57; 95%CI=0.54-4.54; p=0.41) or Caucasians (OR=1.45; 95%CI=0.19-11.22; p=0.72). For subgroup analysis based on HCV (hepatitis C virus) infection status, significant increased risk of OLP was found among patients with mixed HCV infection status (OR=3.77; 95%CI=1.07-13.2; p=0.038), but not in patients without HCV infection (OR=2.09; 95%CI=0.63-6.91; p=0.22) and patients with HCV infection (OR=0.48; 95%CI=0.13-1.69; p=0.25). Conclusion Our results suggest that –308 G/A polymorphism in TNFα is a potential genetic marker for OLP.</p></div

Na₄La₂(CO₃)₅ and CsNa₅Ca₅(CO₃)₈: Two New Carbonates as UV Nonlinear Optical Materials

Two nonlinear optical crystal carbonates (Na₄La₂(CO₃)₅ and CsNa₅Ca₅(CO₃)₈ were successfully synthesized by hydrothermal method, and both of them crystallized in the same noncentrosymmetric hexagonal space group <i>P</i>63<i>mc</i> (No. 186). The structure of Na₄La₂(CO₃)₅ consists of a three-dimensional network made up of [CO₃] triangles as well as irregular [Na_0.67La_0.33O₁₀] and [NaO₈] polyhedra. The structure of CsNa₅Ca₅(CO₃)₈ can be described as the standing-on-edge [CO₃] groups connect the adjacent infinite [CaCO₃]_∞ layers in the <i>ab</i> plane to construct a framework with four types of channels running parallel to [010]. The Na, Cs, and [Na_0.67Ca_0.33] atoms reside in these channels. The measurement of second harmonic generation (SHG) by the method adapted from Kurtz and Perry indicated that Na₄La₂(CO₃)₅ and CsNa₅Ca₅(CO₃)₈ were phase-matchable in the visible region and exhibited SHG responses of approximately 3 and 1 × KH₂PO₄ (KDP). Meanwhile, they exhibited wide transparent region with short UV cutoff edge at about 235 and 210 nm, respectively, suggesting that these crystals as NLO materials may have potential applications in the UV region

Lanthanum Lead Oxide Hydroxide Nitrates with a Nonlinear Optical Effect

Two new lanthanum lead oxide hydroxide nitrates with acentric structure, [LaPb₈O­(OH)₁₀(H₂O)]­(NO₃)₇ (<b>1</b>) and [LaPb₈O­(OH)₁₀(H₂O)]­(NO₃)₇·2H₂O (<b>2</b>), have been prepared under subcritical hydrothermal conditions and crystallize in the space groups of <i>Cc</i> and <i>P</i>2₁2₁2₁, respectively. The crystal structure of compound <b>1</b> consists of the novel [LaPb₈O­(OH)₁₀(H₂O)]⁷⁺ clusters regularly arranged along the <i>ab</i> plane with nitrate ions as the counterions around the clusters by Pb–O bonds, developing into a three-dimensional net framework, while the structure of compound <b>2</b> is composed of [LaPb₈O­(OH)₁₀(H₂O)]⁷⁺ clusters and [NO₃]⁻ groups as the bridging groups, forming a three-dimensional net framework with crystallized water molecules filling in the gaps. The experiments confirmed that compound <b>1</b> is the residue of compound <b>2</b> after efflorenscence. Besides, the [LaPb₈O­(OH)₁₀(H₂O)]⁷⁺ clusters present mirror symmetry in structures of the two compounds. The second-harmonic-generation (SHG) measurements for the two nitrates indicate that the SHG responses for compounds <b>1</b> and <b>2</b> are 1.3 and 1.1 times that of KH₂PO₄, respectively. Theoretical calculations confirmed that the SHG efficiency of compounds <b>1</b> and <b>2</b> mainly arises from the NO₃^– groups in the structure

Lanthanum Lead Oxide Hydroxide Nitrates with a Nonlinear Optical Effect

Two new lanthanum lead oxide hydroxide nitrates with acentric structure, [LaPb₈O­(OH)₁₀(H₂O)]­(NO₃)₇ (<b>1</b>) and [LaPb₈O­(OH)₁₀(H₂O)]­(NO₃)₇·2H₂O (<b>2</b>), have been prepared under subcritical hydrothermal conditions and crystallize in the space groups of <i>Cc</i> and <i>P</i>2₁2₁2₁, respectively. The crystal structure of compound <b>1</b> consists of the novel [LaPb₈O­(OH)₁₀(H₂O)]⁷⁺ clusters regularly arranged along the <i>ab</i> plane with nitrate ions as the counterions around the clusters by Pb–O bonds, developing into a three-dimensional net framework, while the structure of compound <b>2</b> is composed of [LaPb₈O­(OH)₁₀(H₂O)]⁷⁺ clusters and [NO₃]⁻ groups as the bridging groups, forming a three-dimensional net framework with crystallized water molecules filling in the gaps. The experiments confirmed that compound <b>1</b> is the residue of compound <b>2</b> after efflorenscence. Besides, the [LaPb₈O­(OH)₁₀(H₂O)]⁷⁺ clusters present mirror symmetry in structures of the two compounds. The second-harmonic-generation (SHG) measurements for the two nitrates indicate that the SHG responses for compounds <b>1</b> and <b>2</b> are 1.3 and 1.1 times that of KH₂PO₄, respectively. Theoretical calculations confirmed that the SHG efficiency of compounds <b>1</b> and <b>2</b> mainly arises from the NO₃^– groups in the structure

Asymmetric Formal Coupling of β‑Ketoesters with Quinones Promoted by a Chiral Bifunctional N‑Heterocyclic Olefin

A highly enantioselective formal coupling of β-ketoesters with quinones was accomplished by a chiral bifunctional N-heterocyclic olefin organocatalyst. With as low as 1 mol % catalyst loading, a number of enantioenriched quinone derivatives were afforded in good yields with high enantioselectivities and regioselectivities (up to 96% yield, 98% ee, and 19:1 rr). Gram-scale synthesis and the high inhibitory effect of several products on the viability of cancer cells demonstrate the potential utility of the current method

Structural Modulation of Anionic Group Architectures by Cations to Optimize SHG Effects: A Facile Route to New NLO Materials in the ATCO₃F (A = K, Rb; T = Zn, Cd) Series

A new series of alkali-transition metal fluoride carbonates (KCdCO₃F, RbCdCO₃F, KZnCO₃F, and RbZnCO₃F) have been synthesized under subcritical hydrothermal conditions. All crystals are isostructural with the acentric space group <i>P</i>6̅<i>c</i>2 (188). They were structurally characterized by X-ray single crystal diffraction and exhibited the stacking of alternating [AF]_∞(A = K, Rb) and [TCO₃]_∞(T = Zn, Cd) layers connecting adjacent layers by infinite T–F–T (T = Zn, Cd) chains parallel to <i>c</i>-axis. We found that all [TCO₃]­(T = Zn, Cd) building units aligned perfectly parallel in any given layer, but the rotation from one layer to the next resulted in the nonparallel arrangement of [CO₃] groups between two adjacent [TCO₃]_∞ (T = Zn, Cd) layers. In this work, the relative rotation of [CO₃] groups between two successive layers was successfully controlled by introducing cations of different sizes into the structures, which led to different relative rotation angles of [CO₃] groups, yielding varying second harmonic generation (SHG) effects for each fluoride carbonates. The SHG measurement indicates these compounds are all phase-matchable materials in both the visible and the UV region, and the experimental SHG responses are approximately 4.58, 2.84, 1.76, and 0.83 times that of KH₂PO₄ (KDP) for KCdCO₃F, RbCdCO₃F, KZnCO₃F, and RbZnCO₃F, respectively. All new compounds exhibit wide transparent regions ranging from the UV to the near IR, which suggest that they are promising UV NLO materials. In addition, the differences of the structures and NLO properties of A¹⁺M²⁺CO₃F-type crystals were summarized, and their structural design ideas and methods with respect to the structural modulation of anionic group architectures by cations to optimize SHG effects were detailed

A₂Hg_<i>x</i>(SeO₃)_<i>y</i> (A = K, Rb, Cs): Three Alkali Metal Mercury Selenites Featuring Unique 1D [HgO_<i>m</i>(SeO₃)_<i>n</i>]_∞ Chains

Herein, three alkali metal mercury selenites, K2Hg2(SeO3)3, Rb2Hg2(SeO3)3, and Cs2Hg3(SeO3)4, were successfully obtained by a hydrothermal method. The three compounds featured same one-dimensional (1D) [HgOm(SeO3)n]∞ chain structure that consisting of distorted Hg–O polyhedra and SeO3 triangular pyramids with stereochemically active lone pair (SCALP) electrons. Interestingly, the rich coordination environment of Hg atoms and the size difference of alkali metal cations lead to diverse arrangement of SeO3 groups, which makes them exhibit different birefringence. The band gaps of the three compounds indicate that they are potential ultraviolet (UV) optical materials. Detailed theoretical calculations demonstrate that the combined effects of SeO3 triangular pyramids and Hg–O polyhedra are responsible for the optical characteristics of the reported compounds