Evaluation of the deficiency status of 25-hydroxyvitamin D and associated factors in Southwest China: A hospital-based retrospective cross-sectional analysis of a low-latitude, high-altitude, multiracial region.

Vitamin D deficiency is widespread in different populations and regions worldwide and has become a global health issue. The vitamin D status of the population in the Yunnan Province of Southwest China has not been evaluated to date. Therefore, in this study, we evaluated the vitamin D status according to the serum concentrations of 25-hydroxyvitamin D (25(OH)D) in individuals of Yunnan Province, a low-latitude, high-altitude and multiracial region in China. The data on 25(OH)D concentrations from October 2012 to December 2017 were retrospectively collected and assessed using the laboratory information system from 52 950 hospital-based participants (age, 1 day-96 years; females, 73.74%). The serum concentration of 25(OH)D was evaluated using a chemiluminescent immunoassay. The analysis was stratified by sex, age, sampling season, testing year, minority, residential district, latitude, altitude and meteorological factors. Vitamin D status was classified as follows: severe deficiency: <10 ng/mL; deficiency: <20 ng/mL; insufficiency: <30 ng/mL; and sufficiency: ≥30 ng/mL. The results showed that vitamin D deficiency is highly prevalent in Yunnan Province in a hospital-based cohort, with a deficiency and severe deficiency rate of 65.1% and a sufficiency rate of 5.30%. Significantly lower vitamin D levels and sufficiency rates were observed in females than in males (20.13 ± 7.22 ng/mL vs. 17.56 ± 6.66 ng/mL and 8.20% vs. 4.20%; p < 0.01, respectively); in spring and winter (16.93 ± 6.24 ng/mL; 2.97% and 16.38 ± 6.43 ng/mL; 3.06%, respectively) than in summer and autumn (20.23 ± 7.14 ng/mL; 8.02% and 19.10 ± 6.97 ng/mL; 6.61% [p < 0.01], respectively); and in older individuals (0-6 years: 28.29 ± 13.13 ng/mL vs. >60 years: 14.88 ± 8.39 ng/mL; p < 0.01). Relatively higher vitamin D levels were observed in individuals of Yi, Zhuang, Hani, Dai, Miao and Lisu minorities and lower levels in individuals of Hui and Zang minorities compared with those of the Han nationality (p < 0.01). The mean sunlight duration, mean air temperature, maximum ultraviolet value and latitude were significantly correlated with vitamin D levels (r = -0.53, 0.60, 0.31, -0.68, respectively; p < 0.05). These results suggest that vitamin D status is influenced by sex, age, minority, latitude and some meteorological factors in areas with high and low altitudes. Hence, new public health policies, such as advice on sunshine exposure, food fortification and nutrition education, as well as the implementation of vitamin D supplementation programmes must be considered to alleviate vitamin D deficiency in Yunnan province, Southwest China.

N-Heterocyclic Carbene-Palladium Polymers Network: Recyclable Pre-catalyst for Effective Suzuki-Miyaura Coupling Reaction in Water.

Rational design of high-efficiency N-heterocyclic carbene (NHC) palladium catalyst is of great importance to modern organic synthesis, especially in chemical and pharmaceutical industries. Herein, we fabricate a polymer network containing N-heterocyclic carbene palladium (PNNHC-Pd) catalytic active sites via an immobilization process. The N-heterocyclic carbene palladium can serve as a promising linkage of polymer network as well as an effective catalytic active site owing to its structural preference and strong σ-donating ability with palladium species. The results display that N-heterocyclic carbene palladium disperses homogeneously in polymer network, thus rendering PNNHC-Pd excellent catalytic activity, high stability and superior reusability in palladium-catalyzed Suzuki-Miyaura coupling reaction in aqueous medium. This work provides a new insight into the development of heterogenization of homogeneous catalysts based on polymer network.

Role of the CPC sequence in the antioxidant activity of GcGAST protein in E.coli.

Gibberellic acid stimulated transcriptional protein from Gymnadenia conopsea (GcGAST) is a novel member of GA-induced cysteine-rich protein family, which shared 12 highly conserved cysteine residues with other members in C-terminal domain. In the present paper, the recombinant plasmid, as well as two mutants Serine-Proline-Cysteine (SPC) and Cysteine-Proline-Serine (CPS), were constructed to investigate for the first time the effects of the cysteines in Cysteine-Proline-Cysteine (CPC) sequence on the antioxidant activity of GcGAST protein. It was found that E.coli expressing wt GcGAST exhibited significant resistance against exogenous H(2)O(2). Similar phenomenon was observed for E.coli harboring SPC mutant. In contrast, the host cell overexpressing CPS mutant became more sensitive to H(2)O(2). Some studies on the level of inclusion body revealed that wt GcGAST and SPC mutant embedded in Inclusion bodies (IB) could effectively eliminate H(2)O(2), whereas the mutagenesis to Ser of the second Cys residue in CPC sequence gave rise to the compete loss of H(2)O(2)-eliminating ability. Fourier transform Infrared spectroscopy analysis indicated that the IB of CPS mutant contained more ß-sheet secondary structure than wt and SPC mutant. Non-reducing SDS-PAGE combined western-blotting analysis revealed that the disulfide bonds were important for the formation of IBs of wt GcGAST and SPC mutant, whereas non-reducing SDS-PAGE of resolubilized IBs showed that hydrophobic interaction favored the aggregation of IBs in CPS mutant. Taken together, these results suggested that GcGAST possessed antioxidant activity in the level of IB, which made some contribution to cellular resistance to H(2)O(2). More importantly, the second cysteine residue in CPC sequence was more essential for its antioxidant biological function.

[Application of polarization fluorescence to the study on the effects of oxidative stress on wheat chloroplast].

In the present paper wheat flag leaves were collected during the tasseling period, and then 1 mmol x L(-1) hydrogen peroxide was added to induce oxidative stress on leaves. In comparison, the detached leaves were also kept under drought or darkness condition for 24 h for the same purpose. Following the preparation of chloroplasts, polarization fluorescence spectroscopic method was utilized to measure fluorescence emission spectra and fluorescence excitation spectra of chloroplasts in the case of VV, VH, HV and HH, where V and H is representative of vertical polarization and horizontal polarization, respectively. Gaussian deconvolution was done on emission spectra, and the fitting data revealed that no matter whether Chla or Chlb molecules were excited upon excitation at 436 nm or 475 nm, the ratio of fluorescence peak area at 684 nm and 720 nm, i. e. A684/ A720, tends to increase slightly after oxidative stress. In addition, some useful information was available from polarization excitation spectra, where it was observed that the treatment of oxidative stress gave rise to higher ratio of excitation peak intensity between 436 nm and 475 nm (E436/E475), indicating that Chla made more contribution to PSII fluorescence emission than Chlb did. Simultaneously, the ratio of 475 nm and 600 nm (E475/E600), representing the energy transfer efficiency from Car to Chlb, was also found to be higher after the detached leaves were treated. In addition, both fluorescence polarization and viscosity were calculated in this paper, and the data showed that oxidative stress should be responsible for higher fluorescence polarization at 680 nm and higher viscosity in microenviroment. The above-mentioned phenomenon is consistent with the lipid peroxidation of unsaturated fatty acids. It also provides a simple and feasible method to study oxidative stress.

Diaqua-bis(5-carb-oxy-2-methyl-1H-imidazole-4-carboxyl-ato-κN,O)manganese(II).

The title complex, [Mn(C(6)H(5)N(2)O(4))(2)(H(2)O)(2)], was obtained by hydro-thermal synthesis. The Mn(II) atom, which lies on an inversion centre, displays a slightly distorted octa-hedral geometry. In the crystal packing, complex mol-ecules are linked by inter-molecular O-H⋯O and N-H⋯O hydrogen bonds to form a three-dimensional supramolecular structure. The title complex is isostructural with the corresponding cadmium(II) complex [Nie, Wen, Wu, Liu & Liu (2007 ▶). Acta Cryst. E63, m753-m755].

N,N'-Dibenzyl-N,N,N',N'-tetra-methyl-ethylenediammonium dibromide dihydrate.

In the title compound, C(20)H(30)N(2) (2+)·2Br(-)·2H(2)O, the asymmetric unit consists of half of the N,N'-dibenzyl-N,N,N',N'-tetra-methyl-ethylenediammonium cation lying across an inversion center, a bromide ion and a water mol-ecule of solvation. There is an eight-membered dibromide dihydrate ring, which is formed via hydrogen bonds of the type O-H⋯Br.