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Species delimitation remains a challenge worldwide, especially in highly diverse tropical and subtropical regions. Here, we use an integrative approach that combines morphology, phylogenomics, and species distribution modeling (SDM) to clarify the cryptic differentiation within the enigmatic hemiparasitic love vine Cassytha filiformis (Lauraceae) in China and adjacent regions. We generated complete plastid genomes and nuclear ribosomal sequences for diverse samples from across the species range and compared results with previously published plastid data, recovering two well‐supported monophyletic clades. Further, the analysis revealed significant differences in two morphological characters and SDM, indicating distinct environmental factors influencing their distributions. Fossil‐calibrated analyses to estimate the origins and diversification patterns for the cryptic species gave divergence age estimates corresponding to the Oligo‐Miocene; a period of new ecological opportunities associated with the prevailing East Asian monsoon. Multivariate analyses support the conclusion that southern China and adjacent regions have a different, previously unknown, cryptic lineage of C. filiformis. Our study highlights the importance of using multivariate approach to characterize plant species, as well as the significant role that past climatic changes have played in driving speciation in parasitic plants in tropical and subtropical zones. [ABSTRACT FROM AUTHOR]

Summary: Ectomycorrhizal symbiosis, which involves mutually beneficial interactions between soil fungi and tree roots, is essential for promoting tree growth. To establish this symbiotic relationship, fungal symbionts must initiate and sustain mutualistic interactions with host plants while avoiding host defense responses. This study investigated the role of reactive oxygen species (ROS) generated by fungal NADPH oxidase (Nox) in the development of Laccaria bicolor/Populus tremula × alba symbiosis.Our findings revealed that L. bicolor LbNox expression was significantly higher in ectomycorrhizal roots than in free‐living mycelia. RNAi was used to silence LbNox, which resulted in decreased ROS signaling, limited formation of the Hartig net, and a lower mycorrhizal formation rate.Using Y2H library screening, BiFC and Co‐IP, we demonstrated an interaction between the mitogen‐activated protein kinase LbSakA and LbNoxR. LbSakA‐mediated phosphorylation of LbNoxR at T409, T477 and T480 positively modulates LbNox activity, ROS accumulation and upregulation of symbiosis‐related genes involved in dampening host defense reactions.These results demonstrate that regulation of fungal ROS metabolism is critical for maintaining the mutualistic interaction between L. bicolor and P. tremula × alba. Our findings also highlight a novel and complex regulatory mechanism governing the development of symbiosis, involving both transcriptional and posttranslational regulation of gene networks. [ABSTRACT FROM AUTHOR]

Objective. The diagnosis of primary malignant melanoma of the esophagus (PMME) before treatment is essential for clinical decision-making. However, PMME may be misdiagnosed as esophageal squamous cell carcinoma (ESCC) sometimes. This research is aimed at devising a radiomics nomogram model of CT for distinguishing PMME from ESCC. Methods. In this retrospective analysis, 122 individuals with proven pathologically PMME (n = 28) and ESCC (n = 94) were registered from our hospital. PyRadiomics was applied to derive radiomics features from plain and enhanced CT images after resampling image into an isotropic resolution of 0.625 × 0.625 × 0.625 m m 3 . The diagnostic efficiency of the model was evaluated by an independent validation group. Results. For the purpose of differentiation between PMME and ESCC, a radiomics model was constructed using 5 radiomics features obtained from nonenhanced CT and 4 radiomics features derived from enhanced CT. A radiomics model including multiple radiomics features showed excellent discrimination efficiency with AUCs of 0.975 and 0.906 in the primary and validation cohorts, respectively. Then, a radiomics nomogram model was developed. The decision curve analysis has shown remarkable performance of this nomogram model for distinguishing PMME from ESCC. Conclusions. The proposed radiomics nomogram model based on CT could be used for distinguishing PMME from ESCC. Moreover, this model also contributed to helping clinicians determine an appropriate treatment strategy for esophageal neoplasms. [ABSTRACT FROM AUTHOR]

Hepatocytes has been confirmed to undergo EMT and can be converted into myofibroblasts during hepatic fibrogenesis. However, the mechanism of hepatocyte EMT regulation in hepatic fibrosis, particularly through HSP27 (human homologue of rodent HSP25), remains unclear. Mangiferin (MAN), a compound extracted from Mangifera indica L, has been reported to attenuate liver injury. This study aimed to investigate the mechanisms underlying HSP27 inhibition and the anti‐fibrotic effect of MAN in liver fibrosis. Our results revealed that the expression of HSP27 was remarkably increased in the liver tissues of patients with liver cirrhosis and CCl4‐induced fibrotic rats. However, HSP27 shRNA treatment significantly alleviated fibrosis. Furthermore, MAN was found to inhibit CCl4‐ and TGF‐β1‐induced liver fibrosis and reduced hepatocyte EMT. More importantly, MAN decreased HSP27 expression to suppress the JAK2/STAT3 pathway, and subsequently blocked TGF‐β1/Smad signaling, which were consistent with its protection against CCl4‐induced EMT and liver fibrosis. Together, these results suggest that HSP27 may play a crucial role in hepatocyte EMT and liver fibrosis by activating JAK2/STAT3 signaling and TGF‐β1/Smad pathway. The suppression of HSP27 expression by MAN may be a novel strategy for attenuating the hepatocyte EMT in liver fibrosis. [ABSTRACT FROM AUTHOR]

During Drosophila development, Polycomb‐group and Trithorax group proteins function to ensure correct maintenance of transcription patterns by epigenetically repressing or activating target gene expression. To get a deep insight into the PcG and trxG pathways, we investigated a BRCT domain‐containing protein called PTIP, which was generally identified as a transcriptional coactivator and belongs to the TRR complex. At the genome scale, we sorted given PTIP‐binding peaks into two groups: PTIP/TRR‐cobound and PTIP/PC‐cobound peaks. In particular, we found that PTIP mediates the molecular switch between H3K4me3/H3K27ac and H3K27me3 histone modifications at TRR or PC occupied regions. Thus, we suggest that PTIP is a mediator rather than a dedicated co‐activator along PcG and trxG pathways. Our hypothesis is further supported by the genetic assay: PTIP interacts genetically with either PcG or TrxG in a dosage‐dependent manner, suggesting that PTIP functions as a co‐factor of PcG/TrxG proteins. In addition, in accordance with the analysis of ChIP‐seq, these genetic interactions correlate with modified ectopic HOX protein levels in imaginal discs, which reveals an essential role for PTIP in PcG‐mediated Hox gene repression. Hence, we reveal a novel role for PTIP in the epigenetic regulation of gene expression along PcG and trxG pathways. [ABSTRACT FROM AUTHOR]

Electro‐catalyzed oxygen reduction reaction (ORR), as the positive electrode reaction, is significant to the performance of fuel cells and metal‐air batteries. Toward ORR, ultra‐small Pt@Mn core‐shell nanoparticles catalysts supported on Ketjen black are synthesized by a simple one‐pot hydrothermal method. TEM results show that the Pt@Mn/C nanoparticles with an average size of 3∼4 nm are uniformly distributed on the carbon surface. ORR performance of the electrocatalysts shows that Pt@Mn/C exhibits better oxygen reduction activity than Pt/C (20 wt %) in a KOH solution. Methanol tolerance ability as well as the durability of the Pt@Mn/C is also superior to the performance of Pt/C, suggesting an enhanced ORR activity upon the introduction of Mn. [ABSTRACT FROM AUTHOR]

Background: Diffusion weighted imaging (DWI) at multiple b‐values has been used to predict the pathological complete response (pCR) to neoadjuvant chemoradiotherapy for locally advanced rectal cancer. Non‐Gaussian models fit the signal decay of diffusion by several physical values from different approaches of approximation. Purpose: To develop a deep learning method to analyze DWI data scanned at multiple b‐values independent on Gaussian or non‐Gaussian models and to apply to a rectal cancer neoadjuvant chemoradiotherapy model. Study Type: Retrospective. Population: A total of 472 participants (age: 56.6 ± 10.5 years; 298 males and 174 females) with locally advanced adenocarcinoma were enrolled and chronologically divided into a training group (n = 200; 42 pCR/158 non‐pCR), a validation group (n = 72; 11 pCR/61 non‐pCR) and a test group (n = 200; 44 pCR/156 non‐pCR). Field Strength/Sequence: A 3.0 T MRI scanner. DWI with a single‐shot spin echo‐planar imaging pulse sequence at 12 b‐values (0, 20, 50, 100, 200, 400, 600, 800, 1000, 1200, 1400, and 1600 sec/mm2). Assessment: DWI signals from manually delineated tumor region were converted into a signature‐like picture by concatenating all histograms from different b‐values. Pathological results (pCR/non‐pCR) were used as the ground truth for deep learning. Gaussian and non‐Gaussian methods were used for comparison. Statistical Tests: Analysis of variance for age; Chi‐square for gender and pCR/non‐pCR; area under the receiver operating characteristic (ROC) curve (AUC); DeLong test for AUC. P < 0.05 for significant difference. Results: The AUC in the test group is 0.924 (95% CI: 0.866–0.983) for the signature‐like pictures converted from 35 bins, and it is 0.931 (95% CI: 0.884–0.979) for the signature‐like pictures converted from 70 bins, which is significantly (Z = 3.258, P < 0.05) larger than Dapp, the best predictor in non‐Gaussian methods with AUC = 0.773 (95% CI: 0.682–0.865). Data Conclusion: The proposed signature‐like pictures provide more accurate pretreatment prediction of the response to neoadjuvant chemoradiotherapy than the fitted methods for locally advanced rectal cancer. Evidence Level: 3 Technical Efficacy: Stage 2 [ABSTRACT FROM AUTHOR]

Purpose: Manual delineation of a rectal tumor on a volumetric image is time‐consuming and subjective. Deep learning has been used to segment rectal tumors automatically on T2‐weighted images, but automatic segmentation on diffusion‐weighted imaging is challenged by noise, artifact, and low resolution. In this study, a volumetric U‐shaped neural network (U‐Net) is proposed to automatically segment rectal tumors on diffusion‐weighted images. Methods: Three hundred patients of locally advanced rectal cancer were enrolled in this study and divided into a training group, a validation group, and a test group. The region of rectal tumor was delineated on the diffusion‐weighted images by experienced radiologists as the ground truth. A U‐Net was designed with a volumetric input of the diffusion‐weighted images and an output of segmentation with the same size. A semi‐automatic segmentation method was used for comparison by manually choosing a threshold of gray level and automatically selecting the largest connected region. Dice similarity coefficient (DSC) was calculated to evaluate the methods. Results: On the test group, deep learning method (DSC = 0.675 ± 0.144, median DSC is 0.702, maximum DSC is 0.893, and minimum DSC is 0.297) showed higher segmentation accuracy than the semi‐automatic method (DSC = 0.614 ± 0.225, median DSC is 0.685, maximum DSC is 0.869, and minimum DSC is 0.047). Paired t‐test shows significant difference (T = 2.160, p = 0.035) in DSC between the deep learning method and the semi‐automatic method in the test group. Conclusion: Volumetric U‐Net can automatically segment rectal tumor region on DWI images of locally advanced rectal cancer. [ABSTRACT FROM AUTHOR]

Accurate evaluation of tumor response to preoperative chemotherapy is crucial for assigning appropriate patients with colorectal liver metastases (CRLM) to surgery or conservative therapy. However, there is no well‐recognized method for predicting pathological response before surgery. Our study constructed and validated a deep learning algorithm using prechemotherapy and postchemotherapy magnetic resonance imaging (MRI) to predict pathological response in CRLM. CRLM patients from center one who had ≤5 lesions and were scheduled to receive preoperative chemotherapy followed by liver resection between January 2013 and November 2016, were included prospectively and chronologically divided into a training cohort (80% of patients) and a testing cohort (20% of patients). Patients from center two were included January 2017 and December 2018 as an external validation cohort. MRI‐based models were constructed to discriminate according to pathology tumor regression grade (TRG) between the response (TRG1/2) and nonresponse (TRG3/4/5) groups at the lesion level. From center one, 155 patients (328 lesions) were included; chronologically, 101 (264 lesions) in the training cohort and 54 (64 lesions) in the testing cohort. The model achieved better accuracy (0.875 vs 0.578) and AUC (0.849 vs 0.615) than RECIST for discriminating response; it also distinguished the survival outcomes after hepatectomy better than the RECIST criteria. Evaluations of the external validation cohort (25 patients, 61 lesions) also showed good ability with an AUC of 0.833. In conclusion, the MRI‐based deep learning model provided accurate prediction of pathological tumor response to preoperative chemotherapy in patients with CRLM and may inform individualized treatment. What's new? Liver metastasis is a major cause of death in patients with colorectal cancer. Tumor regression grade (TRG) is a good way to assess tumor response and predict patient survival, and is typically measured by pathological evaluation. Here, the authors tested a deep learning algorithm that uses MRI data to obtain TRG in patients with colorectal liver metastasis who were undergoing preoperative chemotherapy. The deep learning model achieved diagnostic accuracy of 87.5%, a big improvement over the previous method, the RECIST criteria (57.8%). This system could help clinicians provide appropriate personalized information to patients about treatment response and prognosis. [ABSTRACT FROM AUTHOR]

Two new photon‐modulated states are introduced by operating a more general coherent superposition (υa+ra†)m on two classical states (coherent and thermal) and their nonclassicality caused by the operation (υa+ra†)m is investigated via examining the squeezing, sub‐Poissonian statistics, nonclassical depth, and negativity of Wigner distribution. Their density‐operator and Wigner‐distribution evolutions in the thermal channel are also explored. It is found that the high‐order operation (υa+ra†)m has better performance in creating nonclassicality for certain ratios r and more robustness against decoherence of the two photon‐modulated states for thermal noise. For convenience, a new three‐variable special polynomial and its generating function are introduced via the normal ordering of operators. [ABSTRACT FROM AUTHOR]

The performance of adding or subtracting photons on two‐mode squeezed thermal states via examining the Einstein–Podolsky–Rosen (EPR) correlation, the Hillery–Zubairy (HZ) correlation, the fidelity of teleportation, and the negativity of Wigner function is theoretically investigated. The normalization factors and the teleportation fidelity are related to Jacobi polynomials, and the (evolved) Wigner functions are simply associated with two‐variable Hermite polynomials. Compared with the original squeezed thermal states, the EPR correlation and the teleportation fidelity can be enhanced by photon subtraction and basically weakened by photon addition symmetric operations, but they cannot be enhanced for both photon addition and subtraction asymmetric cases. Also, HZ correlation can provide a better option relative to the EPR correlation in detecting the entanglement, and the fidelity for teleporting a squeezed state with a large squeezing can also be enhanced via photon addition symmetric operations, in contrast to teleporting a coherent state. Additionally, the nonclassicality is discussed in terms of the negativity of the (evolved) Wigner functions, which shows that photon addition and subtraction and the squeezing cannot restrain the deteriorate of nonclassicality, and the evolved Wigner functions become Gaussian (corresponding to vacuum) with long decay times as a result of amplitude decay. [ABSTRACT FROM AUTHOR]

Aquilegia ecalcarata Maxim. is the only spurless species within the genus Aquilegia and comprises a monophyletic clade with A. yabeana Kitag., A. kansuensis Brühl, and A. rockii Munz. Our previous study on the genetic diversity of those four species revealed that the populations of A. ecalcarata can be divided into two groups, indicating possible genetic difference within A. ecalcarata. However, it is not clear whether the genetic difference is related to the morphological variation among species and groups of A. ecalcarata populations. To answer that question, the morphological variation patterns based on 22 floral and 19 vegetative traits from 42 populations, covering the entire distribution of A. ecalcarata and its relatives, were analyzed in the present study. The result showed that: (i) the differences among the four species were reflected in the floral rather than the vegetative traits; (ii) populations of A. yabeana and A. rockii fell into one cluster each, and each of the six clusters occupied its own distribution range; (iii) one of two A. ecalcarata clusters fell into a subgroup and shared common floral traits with A. rockii; (iv) the individuals of A. ecalcarata form. ecalcarata and form. semicalcarata were often mixed in the same population; and (v) the populations of A. kansuensis were split into two clusters, which differed obviously in floral traits. These results will provide an important morphological basis for the redefinition of species and lay a foundation for the further exploration of the "spurless" A. ecalcarata. [ABSTRACT FROM AUTHOR]

Purpose: To assess stretched-exponential, mono-exponential and intravoxel incoherent motion (IVIM) models of diffusion-weighted MRI(DWI) in predicting pathological complete response (pCR) to neoadjuvant chemoradiotherapy (CRT) in rectal cancer patients.Materials and Methods: This prospective study recruited 98 consecutive patients with locally advanced rectal cancer who underwent 3 Tesla MR examination before, during and after CRT. The apparent diffusion coefficient (ADC), IVIM-derived parameters (D, f, and D*), and stretched-exponential model-derived parameters (DDC and α) were measured. The parameters and their corresponding changes during and after CRT were compared between pCR and non-pCR. Receiver-operating characteristic curve analysis was performed to evaluate the diagnostic performance. Coefficient of variations and intraclass correlation coefficient were calculated to assess reliability and agreement.Results: Nineteen patients achieved pCR while 79 did not. The pCR group had higher ADC and α (ADC2 and α2 ), and their changes (ΔADC2 , and Δα2 ) at the endpoint than non-pCR group. α2 and ADC2 yielded similar AUCs (P = 0.339), Δα2 and ΔADC2 yielded similar AUCs (P = 0.263) ADC and α presented substantial agreement, and α presented the minimum CV (5.0-7.0%).Conclusion: ADC and α were useful for assessing pCR after CRT. α might be more useful because it demonstrated better diagnostic performance than IVIM-derived parameters and better reliability than ADC.Level Of Evidence: 1 Technical Efficacy: Stage 2 J. MAGN. RESON. IMAGING 2017;46:175-183. [ABSTRACT FROM AUTHOR]

Osteoporosis is a skeleton disease affecting 55% of people over age 60, and the number is still increasing due to an ageing population. One method to prevent osteoporosis is to increase the formation of new bone while preventing the resorption of older bone. Thus, osteogenic differentiation of bone marrow‐derived mesenchymal stem cells (BMSCs) is of great importance in improving the treatment of osteoporosis. On the other hand, glucocorticoids (GCs) are widely used to treat the chronic inflammatory disorders, but long‐term exposure to GCs can induce osteoporosis. In present study, we treated BMSCs with dexamethasone (DEX) to simulate GC‐induced osteoporosis. MTT assay, ALP activity, and Alizarin Red were used to evaluate the role miRNA‐291a‐3p in the DEX‐induced osteogenic differentiation suppression. Further, we used qPCR and western blot to investigate the mechanisms of miRNA‐291a‐3p affecting BMSCs differentiation. The results showed that miRNA‐291a‐3p could improve the cell viability, osteogenic differentiation, and ALP activity, which are suppressed by DEX in BMSCs. Furthermore, we found that the osteogenesis genes Runx2, DMP1, and ALP were upregulated whereas the lipogenic genes C/EBPα and PPARγ were downregulated when miRNA‐291a‐3p mimics were transfected. Additionally, we demonstrated that miRNA‐291a‐3p promoted BMSCs' osteogenic differentiation by directly suppressing DKK1 mRNA and protein expression and subsequently activating Wnt/β‐catenin signaling pathway. Our study suggests that miR‐291a‐3p plays an important role in preventing osteoporosis and may serve as a potential miRNA osteoporosis biomarker. [ABSTRACT FROM AUTHOR]

Structurally diverse γ‐ and δ‐lactones were efficiently synthesized stereoselectively using an engineered carbonyl reductase from Serratia marcescens (SmCRV4). SmCRV4 exhibited improved activity (up to 500‐fold) and thermostability toward 14 γ‐/δ‐keto acids and esters, compared with the wild‐type enzyme, with 110‐fold enhancement in catalytic efficiency (kcat/Km) toward methyl 4‐oxodecanoate. The preparative synthesis of alkyl and aromatic γ‐ and δ‐lactones with 95 %–>99 % ee and 78 %–90 % yields was demonstrated. The highest space‐time yield, 1175 g L−1 d−1, was achieved for (R)‐γ‐decalactone. [ABSTRACT FROM AUTHOR]

Patients with ovarian cancer frequently develop acquired drug resistance after the long‐term chemotherapy, leading to disease progression. Enhanced epithelial–mesenchymal transition (EMT) has been implicated in chemoresistance of ovarian cancer cells; however, the molecular mechanisms involved are largely undefined. Pyruvate dehydrogenase kinase 1 (PDK1), a key regulatory enzyme in glucose metabolism, has been recognized as a gatekeeper of the Warburg effect, a hallmark of cancer. In this study, the function of PDK1 in cisplatin resistance of ovarian cancer in terms of growth and EMT was investigated. PDK1 was upregulated in cisplatin‐resistant ovarian cancer cells. PDK1 knockdown in resistant cells led to increased sensitivity to cisplatin‐induced cell death and apoptosis. PDK1 downregulation also reversed the EMT and cell motility in cisplatin‐resistant cells. In a mouse xenograft model, tumors derived from PDK1‐silenced ovarian cancer cells exhibited decreased tumor growth and EMT compared with control after the cisplatin treatment. Mechanistically, PDK1 overexpression led to increased phosphorylation of EGFR, and blocking EGFR kinase activity by erlotinib reversed cisplatin resistance induced by PDK1 overexpression. Furthermore, in patients with ovarian cancer, higher PDK1 and p‐EGFR levels were associated with chemoresistance. These results supported that PDK1 contributes to chemoresistance of ovarian cancer by activating EGFR. Therefore, PDK1 may serve as a promising target to combat chemoresistance of ovarian cancer. Pyruvate dehydrogenase kinase 1 (PDK1) was upregulated in cisplatin‐resistant ovarian cancer. PDK1 knockdown in resistant ovarian cancer cells led to increased sensitivity to cisplatin‐induced cell death and apoptosis, and reversed the epithelial–mesenchymal transition (EMT) and cell motility. There was a feed‐forward PDK1/EGFR crosstalk in ovarian cancer cells that drives cisplatin resistance in terms of both cellular growth and EMT. [ABSTRACT FROM AUTHOR]

The goal of this study was to evaluate the feasibility of detecting Helicobacter pylori clarithromycin resistance in gastric mucosa using the amplification refractory mutation system combined with quantitative real‐time PCR (ARMS‐PCR). Gastric mucosal specimens (150) were collected from patients who were unsuccessfully treated for H. pylori eradication. Each specimen was divided into 2 samples. One sample was used to extract genomic DNA and detect any gene mutations of H. pylori produced by ARMS‐ PCR. Sequencing was used to assess the accuracy of this method. The other sample was used to culture H. pylori. The E‐test minimum inhibitory concentration (MIC) was used to assess clarithromycin resistance. The results were compared with a paired chi‐square test to validate the coincidence rate among the 3 methods. The coincidence rate between the sequencing and ARMS‐PCR results was 98.7%, thus verifying the accuracy of ARMS‐PCR. E‐tests detected 144 clarithromycin resistance cases, including 45 sensitivity cases; the resistance rate was 70%. The coincidence rate between the results of the E‐test and ARMS‐PCR was 97.1%, and no significant difference between the 2 methods was observed. ARMS‐PCR is a simple and fast method that has high sensitivity and specificity and can be used to detect the clarithromycin resistance of H. pylori in gastric mucosa. ARMS‐PCR is expected to be used to study drug resistance mechanisms and use in assays of individual therapies for H. pylori eradication. [ABSTRACT FROM AUTHOR]

Abstract: The genus Aquilegia is emerging as the new model system for plant development, ecology, and evolution studies. Previous research showed that pollinator shift might drive the diversification of North American Aquilegia species, and natural selection on the length of petal nectar spur might play a crucial role. In this genus, A. ecalcarata Maxim. is the only taxon that has lost nectar spurs. Previous phylogenetic results indicated that A. ecalcarata, A. yabeana Kitag., A. oxysepala var. kansuensis Bruhl., and A. rockii Munz comprised a monophyletic group. However, their pattern of genetic diversity remains unknown. In addition, little is known about the evolutionary relationship among the four species on the population level. We carried out a population genetics study with 21 representative populations based on 10 single‐copy nuclear gene fragments and found that: (i) A. yabeana conserved the highest genetic diversity (both πsil and θsil) and A. oxysepala var. kansuensis had the lowest level; (ii) A. ecalcarata split into two groups, with one population clustered with A. rockii and the other five populations clustered with A. oxysepala var. kansuensis; and (iii) the allele frequency spectrum showed an excess of low frequency alleles in all four species, implying that they may undergo the mutation‐drift equilibrium. Our findings provide the first investigation of genetic diversity and evolutionary relationships in A. yabeana, A. oxysepala var. kansuensis, A. rockii, and A. ecalcarata. They lay the foundation for future evolutionary studies, such as speciation mediated by pollinators. [ABSTRACT FROM AUTHOR]

Zirconia ceramic foams with ultra-high porosity of 96%-98% have been fabricated using sodium dodecyl sulfate (SDS) as the particle stabilizer of zirconia particles for the first time. The wet foams stabilized by zirconia particles are ultra-stable due to partially hydrophobic zirconia particles modified by SDS. Zirconia foams exhibit close cells with thin cell wall and small grain size. Increasing SDS concentration favors the foamability of the suspension, and further increases the porosity of ceramic foams. Zirconia ceramic foams with porosity of 98.1% have compressive strength of 0.26 ± 0.05 MPa. Decreasing solid loading leads to the porosity of ceramic foams. The compressive strength could be improved significantly by increasing the sintering temperature. Zirconia ceramic foams with porosity of 97.9% has low thermal conductivity of 0.027 ± 0.004 W·(m·K)-1, which could be used as thermal insulation and refractory material. [ABSTRACT FROM AUTHOR]

Ultralight Si3N4 ceramic foams have been successfully prepared through particle-stabilized foams method, which is based on the adsorption of in situ hydrophobized Si3N4 particles to the liquid/air interface of the foams. Here, we firstly used a long-chain surfactant cetyltrimethylammonium chloride to render the Si3N4 particles partially hydrophobic. By tailoring the surfactant concentration and pH values of the suspensions, the wet foams were stabilized to avoid coarsening and coalescence. SEM results show that the Si3N4 ceramic foams possess single strut walls with elongated β-Si3N4 grains interlocking with each other, and their pores are uniform with an average pore size of 95 μm. The obtained ceramic foams maintain compressive strength of 1.34 ± 0.13 MPa with porosity of 92.0%, when the suspension contains 3 mmol/L surfactant at the pH of 11.0. [ABSTRACT FROM AUTHOR]

Identification of the proteins secreted by the malaria parasite is important for developing effective drugs and vaccines against infection. Therefore, we developed an improved predictor called 'DSPMP' (Discriminating Secretory Proteins of Malaria Parasite) to identify the secretory proteins of the malaria parasite by integrating several vector features using support vector machine-based methods. DSPMP achieved an overall predictive accuracy of 98.61%, which is superior to that of the existing predictors in this field. We show that our method is capable of identifying the secretory proteins of the malaria parasite and found that the amino acid composition for buried and exposed sequences, denoted by AAC( b/ e), was the most important feature for constructing the predictor. This article not only introduces a novel method for detecting the important features of sample proteins related to the malaria parasite but also provides a useful tool for tackling general protein-related problems. The DSPMP webserver is freely available at . © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the effects of endogenous vasoactive substances on the occurrence of intradialytic hypertension ( IDH) in patients during maintenance hemodialysis. Thirty-four maintenance hemodialysis patients were enrolled in this trial, and 17 of them were diagnosed with IDH (defined as an increase in blood pressure of at least 10 mmHg during or immediately after a hemodialysis session), while 17 age-matched and sex-matched controls without IDH were selected for a retrospective comparison. We collected patients' blood samples before and after a dialysis session and measured the plasma levels of N-terminal fragment brain natriuretic peptide, renin, angiotensin-II, aldosterone ( ALD), angiotensin-converting enzyme ( ACE), endothelin-1 ( ET-1), nitric oxide ( NO), norepinephrine ( NOR), and adrenomedullin. The post-dialysis serum ET-1 concentrations were significantly higher (4.09 ± 2.06 vs. 2.75 ± 1.34 pg/mL, P < 0.05), while the post-dialysis ratio of NO to ET-1 was lower (17.79 ± 5.65 vs. 24.78 ± 12.04, P < 0.05) in IDH patients compared with the control group. Post-dialysis ALD and NOR values were significantly lower (P < 0.01) and ACE levels were significantly higher (P < 0.01) than the pre-dialysis concentrations only in the control and not in the IDH group. All other measured factors did not differ significantly between the groups and between pre-dialysis and post-dialysis determinations. Compared with blood angiotensin-II, ALD, ACE, NOR, adrenomedullin, N-terminal fragment brain natriuretic peptide, and NO status, inappropriately elevated ET-1 plasma concentrations may play a predominant role in the pathogenesis of IDH. [ABSTRACT FROM AUTHOR]

Aims To study the contribution of epidermal growth factor receptor variant III ( EGFRv III) to glioblastoma multiforme ( GBM) stemness and gefitinib resistance. Methods CD133+ and CD133− cells were separated from EGFRv III+ clinical specimens of three patients with newly diagnosed GBM. Then, RT- PCR was performed to evaluate EGFRv III and EGFR expression in CD133+ and CD133− cells. The tumorigenicity and stemness of CD133+ cells was verified by intracranial implantation of 5 × 103 cells into immunodeficient NOD/ SCID mice. Finally, cells were evaluated for their sensitivity to EGFR tyrosine kinase inhibition by gefitinib. Results RT- PCR results showed that the sorted CD133+ cells expressed EGFRv III exclusively, while the CD133− cells expressed both EGFRv III and EGFR. At 6-8 weeks postimplantation, CD133+/ EGFRv III+/ EGFR− cells formed intracranial tumors. Cell counting kit-8 results showed that the IC50 values of the three isolated EGFRv III+ cell lines treated with gefitinib were 14.44, 16.00, and 14.66 μM, respectively, whereas the IC50 value of an isolated EGFRv III− cell line was 8.57 μM. Conclusions EGFRv III contributes to the stemness of cancer stem cells through coexpression with CD133 in GBMs. Furthermore, CD133+/ EGFRv III+/ EGFR− cells have the ability to initiate tumor formation and may contribute to gefitinib resistance. [ABSTRACT FROM AUTHOR]

A simple, sensitive and accurate method was developed for the quantification of levodopa and methyldopa (IS) in beagle dog plasma by LC-ESI/MS, chromatographic separation was carried out by a Diamonsil C18 column (150 mm × 4.6 mm i.d., 5 mm) with an ODS guard column maintained at 30 °C. The mobile phase was methanol (A) and 0.5% formic acid aqueous solution (B) system in the gradient elution profile, the retention time of levodopa and IS were 4.8 and 6.1 min, respectively, linear range for levodopa concentration was 0.08-20.0 μg/mL in plasma samples with a correlation coefficient(r) of 0.9978, the limit of detection was 32 ng/mL. CV of intra-day and inter-day assays were all less than 15%, mean recoveries of levodopa were all more than 90% in 0.32, 1.6 and 16.0 μg/mL concentrations of levodopa (n = 3). The validated method was successfully applied to the determination of levodopa in plasma samples, pharmacokinetic of levodopa following a single oral dose of compound levodopa tablets and antiemetic drug - domperidone administrated to beagle dogs has been carried out, the main pharmacokinetic parameters of levodopa with domperidone were as follows: Tmax (0.50 ± 0.18) h, Cmax (39.72 ± 7.91) μg/mL, tl/2 (0.65 ± 0.07) h, AUCo-t (49.01 ± 12.13) μg·h/mL , AUCo-∞ (49.10 ± 12.16) μg·h/mL, we also evaluated the effect of domperidone on pharmacokinetics of levodopa in beagle dog. We thought non-oral sustained-release formulations should be a very good choice instead of this common oral dosage forms on the market, the test results can provide a reference for clinical trials on drug therapy of Parkinson's disease. [ABSTRACT FROM AUTHOR]

ABSTRACT Staphylococcus aureus is the most common cause of hospital-acquired bacteremia. Due to emergence of antibiotic-resistant strains, these infections present a serious public health threat. In this study, to develop a broadly protective vaccine, we tested whether immune responses induced by several proteins associated with S. aureus toxicity could protect mice from lethal challenge with human clinical S. aureus isolate USA300. We found that the surface protein A (SasA) of S. aureus could protect mice from lethal challenge of the bacteria. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

We first investigated liquid chromatography (LC) fingerprint method using multi-wavelength combination technique, and successfully used this method for the analysis of a fat-soluble extract from Radix isatidis. LC fingerprints of fat-soluble R. isatidis extracts from 11 origins were established using the Origin software and Similarity Evaluation System for Chromatographic Fingerprints of traditional Chinese medicine (TCM). The typical LC fingerprints of fat-soluble extracts from R. isatidis were first established, and the reference chromatogram was also generated with 24 common peaks showing large peak areas and good separation from adjacent peaks. Seven common characteristic peaks were identified for the first time: anthranilic acid, syringic acid, benzoic acid, salicylic acid, tryptanthrin, indigo and indirubin. The total peak areas of 24 common peaks were more than 80% of the total peak areas. Hierarchical clustering analysis (HCA) of 11 R. isatidis samples was performed, and the results show that the differences between 11 origin R. isatidis were large. Principal component analysis (PCA) on 24 common peaks was obtained to find the possible chemical markers for the discrimination of different samples. The loading plot indicated that peaks 8, 11, 13 and 14 may have more influence on the discrimination of the samples. All these were useful for evaluating and controlling the quality of R. isatidis. Our work provides a general model of chromatogram combination at multi-wavelength detection to study the complex or the undeveloped materials, which can be used to scientifically ensure the quality of such samples and deeply do qualitative, quantitative and multicomponent pharmacodynamic research combined with modern advanced chromatographic technique. [ABSTRACT FROM AUTHOR]

Abstract: Gene-directed enzyme prodrug therapy (GDEPT) is a strategy developed to selectively target cancer cells. However, the clinical benefit is limited due to its poor gene transfer efficiency. To overcome this obstacle, we took advantage of piggyBac (PB) transposon, a natural non-viral gene vector that can induce stable chromosomal integration and persistent gene expression in vertebrate cells, including human cells. To determine whether the vector can also mediate stable gene expression in ovarian cancer cells, we constructed a PB transposon system that simultaneously expresses the Herpes simplex virus thymidine kinase (HSV-tk) gene and the monomeric red fluorescent protein (mRFP1) reporter gene. The recombinant plasmid, pPB/TK, was transfected into ovarian adenocarcinoma cells SKOV3 with FuGENE HD reagent, and the efficiency was given by the percentage of mRFP1-positive cells detected by flow cytometry and confocal microscopy. The specific expression of HSV-tk in transfected cells was confirmed by RT-PCR and western blotting. The sensitivity of transfected cells to pro-drug ganciclovir (GCV) was determined by methylthiazoletetrazolium (MTT) assay. A total of 56.4±8.4% cells transfected with pPB/TK were mRFP1 positive, compared to no measurable mRFP1 expression in pORF-HSVtk-transfected cells. The expression level of HSV-tk in pPB/TK-transfected cells was ∼10 times higher than in pORF-HSVtk-transfected cells. The results show that pPB/TK transfection increases the sensitivity of cells to GCV in a dose-dependent manner. Our data indicate that the PB transposon system could enhance the anti-tumor efficiency of GDEPT in ovarian cancer. [Copyright &y& Elsevier]

In the present study, the reaction mechanisms as well as regioselectivities of 1,4‐diazabicyclo‐[2.2.2] octane (DABCO) and 4‐dimethylaminopyridine (DMAP)‐catalyzed [2+4] annulation reactions of allenoate with α,β‐unsaturated cyclic ketimine leading to hydropyridine derivatives have been theoretically investigated using density functional theory (DFT). In general, the amine catalyst can initiate the reaction by nucleophilic attack to allenoate leading to zwitterionic intermediate, which can then react with cyclic ketimine following different reaction mechanisms. For DABCO‐catalyzed annulation, the α‐attack is more energetically favorable, and the subsequent two consecutive proton transfers followed by intramolecular cyclization along with catalyst regeneration can lead to the α,β‐[2+4] cycloadduct. While for DMAP‐catalyzed annulation, γ‐attack is preferred, and the subsequent intramolecular cyclization followed by catalyst regeneration results into the β,γ‐[2+4] cycloadduct. The calculated results are consistent with the experimental observations. Further noncovalent interaction (NCI) analyses reveal that the steric repulsion, hydrogen bond interactions, and intramolecular C─H···π interactions as well as π‐π interactions would be responsible for the observed regioselectivities. The DABCO/DMAP‐catalyzed [2+4]‐annulation reactions of allenoate with α,β‐unsaturated cyclic ketimine were theoretically investigated by applying the density functional theory. The reaction mechanisms as well as regioselectivities were explored in detail. [ABSTRACT FROM AUTHOR]

Title compounds (III) and (V) are obtained in moderate to good yields and diastereoselectivities up to <90%. [ABSTRACT FROM AUTHOR]

Pentasubstituted pyrroles, including α-arylpyrroles are prepared from readily available β-enamino compounds and propargyl acetates. [ABSTRACT FROM AUTHOR]

An abstract of the article "Copper-Catalyzed Synthesis of Furo[3,2-c]coumarins and Dihydrofuro[3,2-c]coumarins Through a Propargylation/Alkyne Oxacyclization/Isomerization Cascade Under Microwave Irradiation" by X.-Y. Zhang et al. is presented.

The Streptococcus mutans metE gene encodes methionine synthase (MetE), which catalyzes the direct transfer of a methyl group from methyltetrahydrofolate to homocysteine in the last step of methionine synthesis. metE was cloned into pET28a and the gene product was expressed at high levels in the Escherichia coli strain BL21 (DE3). MetE was purified to homogeneity using Ni2+-chelating chromatography followed by size-exclusion chromatography. Crystals of the protein were obtained by the hanging-drop vapour-diffusion method and diffracted to 2.2 Å resolution. The crystal belongs to space group P21, with unit-cell parameters a = 52.85, b = 99.48, c = 77.88 Å, β = 94.55°. [ABSTRACT FROM AUTHOR]

The title compound, C(26)H(24)N(2)O(3), was synthesized by reduction of the corresponding Schiff base. The mol-ecule does not possess crystallographic or non-crystallographic symmetry. The dihedral angle between the oxygen-bridged benzene rings is 67.98 (8)°. Both hydroxyl groups are involved in O-H⋯O intra-molecular hydrogen bonding. The mol-ecules are linked into a two-dimensional network parallel to the (010) plane by N-H⋯O hydrogen bonds.