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Objective To perform a meta-analysis that investigates the prevalence and seroprevalence of celiac disease (CD) in Chinese general population and high-risk populations, and to summarize data from a serological survey of high-risk populations in Guangdong, China. Methods We collected data from the serological survey of high-risk populations in Guangdong, China (n = 1390) by testing serum tissue transglutaminase immunoglobulin A (tTG-IgA), deamidated gliadin peptides immunoglobulin A (DGP-IgA) and deamidated gliadin peptides immunoglobulin G (DGP-IgG), and also searched Medline, PubMed, Embase, Cochrane and 3 Chinese databases up to December 20, 2020 to estimate the pooled prevalence and seroprevalence of CD in China. Results In the serological survey, 0.94% (13/1390) individuals were positive for CD antibodies. In a meta-analysis of 18 studies, the seroprevalence of CD in Chinese general population was 0.27% (95% CI, 0.02-0.71). The seroprevalence of CD in Chinese high-risk populations was 8.34% (95% CI, 4.90-12.54), significantly higher than that in general population (OR 7.27, 95% CI, 4.06-13.04). The prevalence of biopsied-proven CD in high-risk Chinese populations was 4.44% (95% CI, 1.53-8.58). The seroprevalence of CD was varying with geographic origin, higher in Northern China than that in Southern China. Conclusions The basis for diagnosis of CD in Chinese patients should be through early case-finding by serological screening in high-risk groups; generous serological testing in patients with vague symptoms, especially in Northern Chinese.

To understand the effect mechanisms of long-time running and high operation temperature on performance of the direct methanol fuel cell (DMFC) more clearly and directly, in this paper, a new design of 3-electrode system with a solution-type salt bridge has been developed to distinguish the integral polarization into anodic and cathodic polarizations at various temperatures and explore the attenuation mechanism by in situ monitoring the potential of anode during long-time running process at 80 °C, for the first time. The results indicate that the optimized 3-electrode system consists of a standard calomel electrode (SCE) and a solution-type salt bridge placed in the anode hole filled by 0.5 mol L −1 H 2 SO 4 solution. By utilization of the 3-electrode system, the effect mechanisms of the running temperature and time on electrochemical parameters of the DMFC have been found: (1) The increasing operation temperature improves cathodic performance more significantly than that of anode; (2) the attenuation of fuel cell performance mainly comes from that of anode during the 20-h running test at 80 °C, resulting from the sharp drop of electrochemical active surface area of anode. More important, the new 3-electrode system has simplified the detection equipment and reduced the operating difficulty in a practical application for DMFCs, resulting in its portability.

Aging is an independent risk factor for vascular diseases. Perivascular adipose tissue (PVAT), an active component of the vasculature, contributes to vascular dysfunction during aging. Identification of underlying cell types and their changes during aging may provide meaningful insights regarding the clinical relevance of aging‐related vascular diseases. Here, we take advantage of single‐cell RNA sequence to characterize the resident stromal cells in the PVAT (PVASCs) and identified different clusters between young and aged PVASCs. Bioinformatics analysis revealed decreased endothelial and brown adipogenic differentiation capacities of PVASCs during aging, which contributed to neointimal hyperplasia after perivascular delivery to ligated carotid arteries. Mechanistically, in vitro and in vivo studies both suggested that aging‐induced loss of peroxisome proliferator‐activated receptor‐γ coactivator‐1 α (PGC1α) was a key regulator of decreased brown adipogenic differentiation in senescent PVASCs. We further demonstrated the existence of human PVASCs (hPVASCs) and overexpression of PGC1α improved hPVASC delivery‐induced vascular remodeling. Our finding emphasizes that differentiation capacities of PVASCs alter during aging and loss of PGC1α in aged PVASCs contributes to vascular remodeling via decreased brown adipogenic differentiation.

The Quantum transport of three single metallocene molecule is investigated by performing theoretical calculations using the non-equilibrium Green's function method combined with density functional theory. We find that the three metallocen molecules structure become stretched along the transport direction, the distance between two C p rings longer than the other theory and experiment results. The lager conductance is found in nickelocene molecule, the main transmission channel is the electron coupling between molecule and the electrodes is through the Ni d xz and d yz orbitals and the s , d xz , d yz of gold. This is also confirmed by the highest occupied molecular orbital resonance at Fermi level. In addition, negative differential resistance effect is found in the ferrocene, cobaltocene molecules, this is also closely related with the evolution of the transmission spectrum under applied bias.

Four types of 1,3,5,7-tetrakis(4-aminophenyl)adamantine based covalent-organic frameworks (tapa-COFs) have been designed with diamond, ctn and bor net topologies using the methods of molecular mechanics and density function theory. Their low density (0.096–0.258 g cm−3), high porosity (90–96%) and large H2 accessible surface area (5511–6810 m2 g−1) forecast excellent hydrogen uptake capacities. The grand canonical Monte Carlo (GCMC) simulation revealed that at 77 K tapa-COF-1 possesses the highest gravimetric hydrogen storage capacity at 49.10 wt%, while tapa-COF-3 has the highest volumetric hydrogen storage capacity at 58.66 g L−1. Impressively, at 298 K, tapa-COF-1 and tapa-COF-2 possess rather high gravimetric hydrogen uptake capacities, which exceed both the U.S. Department of Energy’s goal (5.5 wt%) for onboard light-duty vehicles for 2020 and the criterion of 6 wt% for commercial use of hydrogen at room temperature. In addition, the possible schemes are also proposed to synthesize the tapa-COFs.

A new development in the palladium-catalyzed allylation reaction of trifluoromethylated ketene aminoacetals was reported. These nucleophilic reagents were prepared by adding aminoalcohols to methyl 3,3,3-trifluoro-2-trifluoromethylpropanoate. The asymmetric version of the allylation reaction was investigated using chiral oxazolidine-based starting materials or chiral palladium catalysts. Asymmetric allylic alkylation was carried out with up to 74% ee using a chiral catalyst. However, no improvement was observed using double stereodifferentiation. These results provided a novel access for trifluoromethylated all-carbon quaternary carbon centers.

Cell-targeted therapies (smart drugs), which selectively control cancer cell progression with limited toxicity to normal cells, have been developed to effectively treat some cancers. However, many cancers such as metastatic prostate cancer (PC) have yet to be treated with current smart drug technology. Here, we describe the thorough preclinical characterization of an RNA aptamer (A9g) that functions as a smart drug for PC by inhibiting the enzymatic activity of prostate-specific membrane antigen (PSMA). Treatment of PC cells with A9g results in reduced cell migration/invasion in culture and metastatic disease in vivo. Importantly, A9g is safe in vivo and is not immunogenic in human cells. Pharmacokinetic and biodistribution studies in mice confirm target specificity and absence of non-specific on/off-target effects. In conclusion, these studies provide new and important insights into the role of PSMA in driving carcinogenesis and demonstrate critical endpoints for the translation of a novel RNA smart drug for advanced stage PC.

A new type of 1,3,5,7-tetraphenyladamantane-based covalent organic framework (adm-COF) was designed under the ctn and bor net topology with the method of molecular mechanics. The computed results reveal that all four designed adm-COFs exhibit extremely high porosity (86–95%) and large H2 accessible surface area (5967–6709 m2 g−1). The grand canonical Monte Carlo method was employed to simulate the adsorption isotherms of H2 gas in these adm-COFs at 77 K and 298 K. The simulated results indicate that, at 77 K and 100 bar, adm-COF-4 has the highest gravimetric H2 adsorption capacity of 38.36 wt%, while adm-COF-1 has the highest volumetric H2 adsorption capacity of 60.71 g L−1. Impressively, the gravimetric H2 adsorption capacity of adm-COF-1 can reach up to 5.81 wt% under 100 bar at room temperature, which is very close to the criterion of 6 wt% for the practical application of hydrogen at room temperature set by the U.S. Department of Energy. In addition, possible schemes for synthesizing these adm-COFs have been proposed.

An intumescent flame retardant (IFR), pentaerytheritol phosphate ester melamine salt (PPEM) was synthesized and chemically modified by magnesium oxide (MgO) or/and calcium oxide (CaO), respectively. The fire retardant efficiency of MgO and CaO as synergistic agents in polypropylene (PP) was evaluated by normal fire testing methods. The results showed that MgO and CaO exhibited a synergistic effect on fire retardancy of PP. The addition of 0.2% of MgO or CaO into PP/PPEM composite could decrease the self-extinguishing time and improve the limited oxygen index (LOI) obviously. The cone calorimeter (CONE) tests and the thermal analysis revealed that the introduction of MgO and CaO neutralized the acidity of PPEM, which leads to a thermal stabilization and a delay of the intumescent process of the system, and promote the formation of a high quality charred layer which can prevent PP from decomposing. Thus, a suitable amount of MgO and CaO acts as a synergistic agent in the flame-retarded PP/PPEM system. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

In this study, we examined differences in serum laminin expression in patients with intractable epilepsy. Our results suggest that elevated laminin may contribute to the pathogenesis of intractable epilepsy. ELISA and western blots were used to measure laminin in the serum of 30 intractable epilepsy patients, 46 nonintractable epilepsy patients, and 20 normal subjects. By ELISA, serum laminin levels were greater in intractable epilepsy patients (177.396 +/- 30.602) and nonintractable epilepsy patients (121.915 +/- 35.215) than in normal control subjects (67.474 +/- 7.197); laminin was significantly greater in the intractable epilepsy group than in the nonintractable epilepsy group. In western blots, the optical density ratio of laminin to ss-actin was 0.871 +/- 0.032 for the intractable epilepsy group, 0.686 +/- 0.017 for the nonintractable epilepsy group, and 0.385 +/- 0.024 for the normal control group. The optical density ratios of the intractable and nonintractable epilepsy groups were higher than those for the normal control group, and the intractable epilepsy group was even greater than the nonintractable epilepsy group. Thus, laminin is significantly increased in epilepsy patients, and this increase is more profound in intractable epilepsy patients.

An algebraic method (AM) used to study the full vibrational spectra of diatomic systems, and an analytical formula used to calculate accurate molecular dissociation energies are applied to study the full vibrational spectra and molecular dissociation energies of some electronic states of homonuclear and heteronuclear diatomic molecules and diatomic ions. Studies show that the AM method and the analytical expression are reliable and economical physical methods for studying full vibrational spectra and molecular dissociation energies of diatomic electronic systems theoretically. They are particularly useful for those diatomic systems whose high-lying vibrational energies may not be available.

The general mixed linear model can be written as y=Xβ+Zu+e. In this paper, we mainly deal with two problems. Firstly, the problem of predicting a general linear combination of fixed effects and realized values of random effects in a general mixed linear model is considered and an explicit representation of the best linear unbiased predictor (BLUP) is derived. In addition, we apply the resulting conclusion to several special models and offer an alternative to characterization of BLUP. Secondly, we recall the notion of linear sufficiency and consider it as regards the BLUP problem and characterize it in several different ways. Further, we study the concepts of linear sufficiency, linear minimal sufficiency and linear completeness, and give relations among them. Finally, four concluding remarks are given.

Three carboxylate silver(I) complexes, [Ag(fbc)]n, (1), [Ag2(cpd)]n (2) and [Ag2(idc)]n (3), were prepared and characterized by X‐ray single crystal analysis, where fbcH is 4‐fluorobenzoic acid, cpdH2 is cyclopentane‐1,1‐dicarboxylic acid and idcH2 is iminodiacetic acid. The three coordination polymers show clear Ag–Ag bonds in their structures. The Ag–Ag bond length 2.850 A both in 1 and 2 is much shorter than that (2.89 A) in metal silver, which is the shortest silver–silver interaction reported. The result of cytotoxicity of the three complexes indicates that they have very high crytotoxicity properties to normal cells and carcinoma cells.

Two cobalt(II) complexes, [Co3L4(APYH)2](SO4)2 (1) and [Co3L4(APY)2](ClO4)2 (2), where APY is 2‐aminopyridine and L is N‐salicylaldehyde‐2‐iminopyridine anion, were prepared and characterized by single crystal structure determination. The crystallographic study shows that each of the two complexes consists of a discrete trinuclear cobalt(II) dication, two sulfate anions in (1) or two perchlorate anions in (2). The similar cations in the two complexes are composed of three cobalt(II) atoms, four tridentate Schiff base ligands (L), and two protonated 2‐aminopyridines for (1) or two 2‐aminopyridine molecules for (2). The authors thank the Education Office of Anhui Province, People's Republic of China for research grant no. 2004kj300zd, and the Natural Science Foundation of Hubei Province, People's Republic of China, for research grant no. 2003ABB010.

The reaction of Ag2O and carboxylate ligands in ammonium solution results in three coordination polymers, [Ag(fbc)]n 1, [Ag2(cpd)]n 2 and [Ag2(idc)]n 3, where fbcH is 4-fluorobenzoic acid, cpdH2 is cyclopentane-1,1-dicarboxylic acid and idcH2 is iminodiacetic acid. The X-ray crystal structural analysis indicates that compounds 1 and 2 are two-dimensional frameworks and 3 is a three-dimensional framework. All the three complexes show clear Ag–Ag bonds and high cytotoxicity properties to normal cells and carcinoma cells.

Coordination compounds of the coinage monovalent ions have received considerable attention in the last three decades. In particular, the study of their biological activity is of importance. In the ...

Lack of vaccines for HCV and HIV makes the antiviral drug development urgently needed. The recently identified HCV NS5A-derived virucidal peptide (C5A) demonstrated a wide spectrum of activities against viruses. In this study, the C5A sequence SWLRDIWDWICEVLSDFK was utilized as the framework to study the effect of the modulation of peptide helicity and hydrophobicity on its anti-HCV and anti-HIV activities. Peptide helicity and hydrophobicity were altered by substitutions of varying amino acids on the non-polar face of C5A. Peptide hydrophobicity has been proved to play a crucial role in peptide anti-HCV or anti-HIV activities. Peptide helicity was relatively independent with antiviral activity. However, peptide analogs with dimerized structure in an aqueous medium while maintaining the ability to be induced into a more helical structure in a hydrophobic environment may tend to show comparable or improved antiviral activity and specificity to C5A. By modulating peptide helicity and hydrophobicity, we improved the specificity of C5A against HCV and HIV by 23- and 69-fold, respectively, in terms of the ratio of hemolytic activity to antiviral activity. We demonstrated that obtained by de novo design approach, peptide I6L/I10L/V13L may be a promising candidate as a new anti-HCV and anti-HIV therapeutic.

The title compound, [Zn(C11H7O3)2(H2O)2], is a mononuclear zinc(II) complex, with the Zn atom on a twofold rotation axis, coordinated by two O atoms from two water mol­ecules and two O atoms from two 3-hydroxy­naphthalene-2-carboxyl­ate ligands, in a distorted tetrahedral geometry. The crystal structure is stabilized by O—H⋯O hydrogen bonds, forming a two-dimensional network.