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Three series of novel AHL analogs were synthesized and evaluated for their in vitro cytotoxic activity against four human cancer cell lines. The SARs investigation indicated that AHLs with a terminal phenyl group, especially those with the chalcone scaffold had remarkably enhanced cytotoxicity than those with the hydrophobic side chains. Besides, some of these compounds were much more potent than 5-Fu and natural OdDHL. Through the detailed SARs discussions, we found that compounds 10a-k and 14 with the 4-amino chalcone scaffold showed excellent inhibition against all the tested cancer cell lines and were much more potent than 5-Fu and AHLs. Such scaffold may act as a template for further lead optimization. Compound 10i with a 3, 4, 5-trimethoxy group was the most potent one against all the tested cancer cell lines. Flow cytometry analysis indicated that analog 11e induced the cellular apoptosis and cell cycle arrest of MCF-7 cells at G2/M phase in a concentration-and time-dependent manner. [ABSTRACT FROM AUTHOR]

A boundary value problems for functional differenatial equations, with nonlinear boundary condition, is studied by the theorem of differential inequality. Using new method to construct the upper solution and lower solution, sufficient conditions for the existence of the problems' solution are established. A uniformly valid asymptotic expansions of the solution is also given. [ABSTRACT FROM AUTHOR]

Abstract: Two series of novel AHL analogues were designed, synthesized and evaluated for antibacterial activity under cell membrane conditions in vitro. Analogues 4a–c and 4g–m presented potent activity against Gram-positive bacteria. Especially the analogue 4l exerted the most potent inhibition against Bacillus subtilis with MIC50 value of 1.443μg/ml. To our surprise, analogues 6a–c and 6g showed weak inhibition against Gram-negative bacteria with MIC50 values ranging from 17.589 to 67.840μg/ml. This was the first report about synthesis and antibacterial evaluation in vitro of AHL analogues containing dithioester linkage. [Copyright &y& Elsevier]

In CSAMT exploration, the using of the artificial sources not only improves the signal-to-noise ratio of the data, but also brings a series of distortion effects, such as shadow and source overprint effects. This paper attempts to introduce a distortion effect caused by the target in the survey area. Although it is often ignored, it always plagues the data interpretation. In CSAMT method, the primary current has determined direction due to the source. When the primary current encounters electrical interfaces, the induced charge will accumulate on it and generate local current, causing local distortion. The anomaly body stretches in the direction of the vertical primary current, and a false anomaly with opposite polarity appears on both sides of the target. If the direction of the primary current is different, the accumulation position of the induced charge is also different, which will result in different shapes of the anomalies in observed data. This paper confirms the existence of the distortion by taking four simple models as examples and explains it from the physical mechanism. On this basis, the paper summarizes the relationship between inversion and distortion. If our code can simulate the distortion effect in the forward, we do not need to remove it before the inversion. Otherwise, it must be removed. [ABSTRACT FROM AUTHOR]

Abstract: Two series of steroidal dienamides 4a–q and 5a–f were designed, synthesized and evaluated for cytotoxic activities against five human cancer cell lines (MGC-803, EC109, PC-3, SMMC-7721 and MCF-7). The protocol developed efficiently achieved the construction of carbon–carbon double bond and selective conversion of nitrile group into carboxamide in one-pot procedure. Besides, compounds 4a–q and 5a–f showed moderate to excellent cytotoxic activities with the IC50 values ranging from 0.1 to 40 μM and most of them were more potent than 5-fluorouracil. Particularly, four compounds 4d, 4e, 4q and 5a showed excellent selectivity against MGC-803 with the IC50 values less than 1 μM. Flow cytometry analysis demonstrated that compound 4c caused the cellular early apoptosis and cell cycle arrest in G2/M phase in a concentration-independent manner. [Copyright &y& Elsevier]

Background: Cancers from lung and esophagus are the leading causes of cancer-related deaths in China and share many similarities in terms of histological type, risk factors and genetic variants. Recent genome-wide association studies (GWAS) in Chinese esophageal cancer patients have demonstrated six high-risk candidate single nucleotide polymorphisms (SNPs). Thus, the present study aimed to determine the risk of these SNPs predisposing to lung cancer in Chinese population. Methods: A total of 1170 lung cancer patients and 1530 normal subjects were enrolled in this study from high-incidence areas for esophageal cancer in Henan, northern China. Five milliliters of blood were collected from all subjects for genotyping. Genotyping of 20 high-risk SNP loci identified from genome-wide association studies (GWAS) on esophageal, lung and gastric cancers was performed using TaqMan allelic discrimination assays. Polymorphisms were examined for deviation from Hardy-Weinberg equilibrium (HWE) using Х2 test. Bonferroni correction was performed to correct the statistical significance of 20 SNPs with the risk of lung cancer. The Pearson’s Х2 test was used to compare the distributions of gender, TNM stage, histopathological type, smoking and family history by lung susceptibility genotypes. Kaplan-Meier and Cox regression analyses were carried out to evaluate the associations between genetic variants and overall survival. Results: Four of the 20 SNPs identified as high-risk SNPs in Chinese esophageal cancer showed increased risk for Chinese lung cancer, which included rs3769823 (OR = 1.26; 95% CI = 1.107–1.509; P = 0.02), rs10931936 (OR = 1.283; 95% CI = 1.100–1.495; P = 0.04), rs2244438 (OR = 1.294; 95% CI = 1.098–1.525; P = 0.04) and rs13016963 (OR = 1.268; 95% CI = 1.089–1.447; P = 0.04). All these SNPs were located at 2q33 region harboringgenes of CASP8, ALS2CR12 and TRAK2. However, none of these susceptibility SNPs was observed to be significantly associated with gender, TNM stage, histopathological type, smoking, family history and overall survival. Conclusions: The present study identified four high-risk SNPs at 2q33 locus for Chinese lung cancer and demonstrated the shared susceptibility loci at 2q33 region for Chinese lung and esophageal cancers. [ABSTRACT FROM AUTHOR]

Background: Obstructive jaundice (OJ) is insensitive to radiation and chemotherapy, and a pathologic diagnosis is difficult to make clinically. Percutaneous transhepatic cholangiobiopsy (PTCB) is simple to perform and minimally invasive, and clinical practice has shown it to be an accurate and reliable new method for bile duct histopathologic diagnosis. Purpose: To investigate the value of PTCB for pathologic diagnosis of causes of OJ. Material and Methods: From April 2001 to December 2011, PTCB was performed in 826 consecutive patients. Data on pathologic diagnosis, true positive rate, and complications were analyzed retrospectively. Patients with negative pathologic findings were diagnosed using clinical, imaging, laboratory, and prognostic data. The feasibility and safety of PTCB for OJ were evaluated and true positive rates for biliary carcinoma and non-biliary carcinoma compared. Results: PTCB was successful in all cases. Of 740 patients clinically diagnosed with malignant biliary stricture and 86 with benign biliary stricture, 727 received a positive pathologic diagnosis; in 99, the pathologic findings were considered false negative. The true positive rate for PTCB was 88.01% overall, differing significantly for biliary and non-biliary carcinoma (χ2 = 12.87, P < 0.05). Malignancy accounted for 89.59% of OJ cases; well, moderately, and poorly differentiated carcinoma represented 57.88%, 19.97%, and 22.15%. Biliary adenocarcinoma was the predominant malignant pathologic type (96.41%). Transient bilemia, bile leakage, and temporary hemobilia occurred in 47, 11, and 28 cases, respectively, with no serious complications. Conclusion: PTCB is safe, feasible, and simple, with a high true positive rate for definitive diagnosis of OJ causes. Well differentiated adenocarcinoma was the predominant pathologic type. [ABSTRACT FROM AUTHOR]

The devices would subject transient thermal shocks (TTS) during operation under extremely harsh conditions of nuclear fusion reactors, which inevitably exert significant impact on the microstructure and performance of structural materials. In this work, a reduced activation VCrFeTa 0.2 W 0.2 high-entropy alloy (HEA) was developed by vacuum arc melting. The effects of electron beam induced TTS on its microstructure, microhardness, and corrosion properties were investigated. The results indicate that the weight fraction of each phase changes after TTS, showing a significant decrease in the content of BCC1 phase and an increase in the content of BCC2 and Laves phases. The content of BCC1 phase continues to decrease slightly with increasing the power of TTS. Besides, the microhardness of the alloy increases from ~673 HV to ~714 HV after TTS treatments. In the reduced activation HEA, TTS results in a relatively low corrosion current density of ~0.472 μA/cm2 in 3.5 wt% NaCl solution, around one-third of the current density observed in the as-cast sample. Furthermore, the VCrFeTa 0.2 W 0.2 HEA after TTS exhibits a pitting potential of ~1.165 V SCE , which is much higher than that of the as-cast sample. The refined composite multiscale entropy method is employed to analyze the influence of TTS on current fluctuation behavior during the corrosion process. The reduced activation VCrFeTa 0.2 W 0.2 HEA exhibits excellent properties in harsh environments after TTS, thereby showing advantageous property in the field of nuclear structural materials. Moreover, TTS is an efficient and controllable strategy for the improvement of the HEAs' microstructures and performances. • A reduced activation VCrFeTa 0.2 W 0.2 high-entropy alloy is developed. • Transient thermal shock is used to change the microstructure. • Microhardness of the alloy increases from ~ 673 HV to ~ 714 HV. • The corrosion resistance of the alloy is improved by transient thermal shock. • Refined composite multiscale entropy method is used to analyze the corrosion behavior. [ABSTRACT FROM AUTHOR]

Background: The human major histocompatibility complex (MHC) is the most important region in vertebrate genome, and is crucial in innate immunity. Recent studies have demonstrated the possible role of polymorphisms in the MHC region to high risk for esophageal squamous cell carcinoma (ESCC). Our previous genome-wide association study (GWAS) has indicated that the MHC region may confer important risk loci for ESCC, but without further fine mapping. The aim of this study is to further identify the risk loci in the MHC region for ESCC in Chinese population. Methods: Conditional logistic regression analysis (CLRA) was performed on 24 single nucleotide polymorphisms (SNPs) within the MHC region, which were obtained from the genetically matched 937 cases and 692 controls of Chinese Han population. The identified promising SNPs were further correlated with clinical and clinicopathology characteristics. Immunohistochemistry was performed to explore the protein expression pattern of the related genes in ESCC and neighboring normal tissues. Results: Of the 24 promising SNPs analyzed, we identified three independent SNPs in the MHC region associated with ESCC: rs35399661 (P = 6.07E-06, OR = 1.71, 95%CI = 1.36–2.17), rs3763338 (P = 1.62E-05, OR = 0.63, 95%CI = 0.50–0.78) and rs2844695 (P = 7.60E-05, OR = 0.74, 95%CI = 0.64–0.86). These three SNPs were located at the genes of HLA-DQA1, TRIM27, and DPCR1, respectively. Further analyses showed that rs2844695 was preferentially associated with younger ESCC cases (P = 0.009). The positive immunostaining rates both for HLA-DQA1 and TRIM27 were much higher in ESCC tissues than in neighboring normal tissues (69.4% vs. 26.8% for HLA-DQA1 and 77.6% vs. 47.8% for TRIM27, P<0.001). Furthermore, the overexpression of HLA-DQA1 is correlated significantly with age (P = 0.001) and family history (P<0.001). Conclusion: This study for the first time provides evidence that multiple genetic factors within the MHC region confer risk to ESCC on the subjects from high-risk area in northern China. [ABSTRACT FROM AUTHOR]

Abstract: A simple and practical method for synthesis of the D-ring modified steroidal dienamides (4a–k) from the steroidal α,α-dicyanoalkene 3 and aldehydes via vinylogous aldol reaction was first reported. By using NaOAc as a base, the desired products were obtained in moderate to good yields in ethanol under mild conditions. All the synthesized steroidal dienamides are new and are currently being evaluated for their biological activities. [Copyright &y& Elsevier]

Abstract: A series of novel 1,2,4-triazolo [3,4-a] phthalazine derivatives were synthesized in five steps from a common precursor, phthalic anhydride. Most of synthesized phthalazine derivatives showed inhibitory activity against Staphylococcus aureus. One of phthalazine derivatives 5l showed inhibitory activity against all tested bacterial and fungal strains. [Copyright &y& Elsevier]

A correction to the article "A correction to the article "Genome-wide association analyses of esophageal squamous cell carcinoma in Chinese identify multiple susceptibility loci at PLCE1 and C20orf54" published in the August 22, 2014 issue of the periodical is presented.

12 Title compounds are prepared and tested for their antimicrobial activities. [ABSTRACT FROM AUTHOR]

The methanolysis of azetidinone-fused oxazoline (II) affords dipeptide (IV), which is readily converted into novel butenolide (V) and its 5-substituted derivatives (VII)/(VIII). [ABSTRACT FROM AUTHOR]