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1.
Food Chem ; 303: 125399, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31470274

RESUMO

It is still a challenge to solve the matrix interferences in veterinary drug residue analysis. In this study, we reported a thin layer chromatography (TLC)-high-performance liquid chromatography (HPLC) method for determining total florfenicol (FF) residues, expressed as florfenicol amine (FFA), in porcine edible tissues. The tissue homogenate were acid-hydrolyzed to liberate the bound residues and convert them into FFA. The hydrolysates were washed with ethyl acetate and subsequently extracted with ethyl acetate under alkaline conditions. The supernatants were concentrated through evaporation, defatted with hexane, purified by TLC and analyzed by HPLC at 225 nm. The optimal developing solvent for TLC purification was ethyl acetate-acetone-ammonium hydroxide mixtures (2:8:0.5, v/v/v). The method was fully validated according to decision 2002/657/EC, and could be used for the routine monitoring of FF residues in pig. TLC showed excellent purification efficiency, and was expected to solve the matrix interferences in veterinary drug residue analysis.

2.
Food Chem ; 306: 125611, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31606631

RESUMO

Aromatic secondary metabolites are closely related to quality attributes of postharvest fruit. In the present study, 20% CO2 was applied to strawberry fruit to investigate the regulation of elevated CO2 on aromatic secondary metabolites. The results showed that elevated CO2 delayed accumulations of anthocyanins, eugenol and lignin. Phenylalanine and tyrosine, the precursors of the above secondary metabolites, were 18.90% and 35.61%, respectively, lower in CO2-treated fruit compared with the control on day 6. Furthermore, enzyme activities and transcriptional profiles analysis showed pentose phosphate pathway and glycolysis were activated by elevated CO2 whereas the aromatic amino acids (AAAs) pathway was inhibited. These results indicated that elevated CO2 restricted carbon flux into aromatic secondary metabolism by inhibiting the AAAs pathway, leading to the decrease of phenylalanine and tyrosine, and thus, delayed the accumulation of aromatic secondary metabolites. In addition, the effect of elevated CO2 was eliminated after transferred CO2-treated fruit to air.

3.
Food Chem ; 307: 125550, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31639575

RESUMO

Modified atmosphere has widely been evident to contribute to fruit quality maintenance, however the correlation among these quality traits was less known. To explore main factors of elevated atmosphere and reduce the detection indexes, we exposed strawberry to either high O2 (80% O2 + 20% N2) or CO2 (20% CO2 + 20% O2 + 60% N2) atmosphere and compared quality characteristics. It was demonstrated that both atmospheres well maintained the fruit firmness, alleviated weight loss and decay rate. Elevated O2 maintained the polyphenolic contents and cell integrity by significantly decreasing superoxide and hydrogen peroxide levels. PCA analysis implied that HO treatment mainly affected oxygen metabolism while HCO affected carbon metabolism more. Significantly positive correlation was observed between weight loss, anthocyanin content and decay rate in elevated O2 and control groups. This study provided new insights into correlation and difference between impact of elevated O2 and CO2 to postharvest preservation.

4.
Cancer Med ; 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31670906

RESUMO

BACKGROUND: Cervical cancer is one of the most common causes of cancer-associated mortality among affected women in the world. At present, treatment with weekly cisplatin plus ionizing radiation (IR) therapy is the standard regimen for cervical cancer, especially for locally advanced cervical cancer. The purpose of this study is to determine whether FEN1 inhibitors could enhance the therapeutic effect of IR therapy. METHODS: Western blot was applied to determine the expression of FEN1- and apoptosis-related proteins. Cell growth inhibition assay and colony formation assay were used to determine the effects of FEN1 inhibitor and IR exposure for Hela cells in vitro. CRISPR technology was used to knockdown FEN1 expression level of 293T cells, and tumor xenograft in nude mice was employed to determine the effects of FEN1 inhibitor and IR exposure on tumor growth in vivo. RESULTS: Our data revealed that FEN1 is overexpressed in HeLa cell and can be upregulated further by IR. We also demonstrated that FEN1 inhibitor enhances IR sensitivity of cervical cancer in vitro and in vivo. CONCLUSION: FEN1 inhibitor SC13 could sensitize radiotherapy of cervical cancer cell.

5.
J Clin Microbiol ; 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31578261

RESUMO

Vaccination with inactivated vaccines is still the main measure to control foot-and-mouth disease (FMD) in endemic areas, and the level of neutralizing antibody in vaccinated animals is directly related to their protection against virus challenge. Currently, neutralizing antibody is mainly detected using virus neutralization test (VNT) based on cell culture, which is laborious, time-consuming and requiring restrictive biocontainment facilities. In this study, two broadly neutralizing antibodies (bnAbs) E46 and F128 were successfully produced using single B cell isolation techniques from peripheral blood mononuclear cells (PBMCs) of bovine sequentially immunized with three topotypes of foot-and-mouth disease virus (FMDV) serotype O. Based on these bnAbs, a blocking ELISA for detecting neutralizing antibodies (NA-ELISA) against FMDV serotype O was developed. The specificity and sensitivity of the test were estimated as 99.21% and 100%, respectively. A significant correlation (P<0.01) was observed between the NA-ELISA titers and the VNT titers for all sera from vaccinated animals and for all tested strains, suggesting that NA-ELISA could detect neutralizing antibodies against FMDV serotype O strains of wide antigenic and molecular diversity, and could be used for the evaluation of protective immunity.

6.
Clin Drug Investig ; 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31586305

RESUMO

BACKGROUND AND OBJECTIVE: Because of the narrow therapeutic window and huge inter-individual variation, the individual precision on anticoagulant therapy of warfarin is challenging. In our study, we aimed to construct a Back Propagation Neural Network (BPNN) model to predict the individual warfarin maintenance dose among Chinese patients who have undergone heart valve replacement, and validate its prediction accuracy. METHODS: In this study, we analyzed 13,639 eligible patients extracted from the Chinese Low Intensity Anticoagulant Therapy after Heart Valve Replacement database, which collected data on patients using warfarin after heart valve replacement from 15 centers all over China. Ten percent of patients who were finally enrolled in the database were used as the external validation, while the remaining were randomly divided into the training and internal validation groups at a ratio of 3:1. Input variables were selected by univariate analysis of the general linear model; 2.0, the mean value of the international normalized ratio (INR) range 1.5-2.5, was used as the mandatory variable. The BPNN model and the multiple linear regression (MLR) model were constructed by the training group and validated through comparisons of the mean absolute error (MAE), mean squared error (MSE), root mean squared error (RMSE), and ideal predicted percentage. RESULTS: Finally, 10 input variables were selected and a three-layer BPNN model was constructed. In the BPNN model, the value of MAE (0.688 mg/day and 0.740 mg/day in internal and external validation, respectively), MSE (0.580 mg/day and 0.599 mg/day in internal and external validation, respectively), and RMSE (0.761 mg/day and 0.774 mg/day in internal and external validation, respectively) were achieved. Ideal predicted percentages were high in both internal (63.0%) and external validation (59.7%), respectively. Compared with the MLR model, the BPNN model showed a higher ideal prediction percentage in the external validation group (59.7% vs. 56.6%), and showed the best prediction accuracy in the intermediate-dose subgroup (internal validation group: 85.2%; external validation group: 84.7%) and a high predicted percentage in the high-dose subgroup (internal validation group: 36.2%; external validation group: 39.8%), but poor performance in the low-dose subgroup (internal validation group: 0%; external validation group: 0.3%). Meanwhile, the BPNN model showed better ideal prediction percentage in the high-dose group than the MLR model (internal validation: 36.2% vs. 31.6%; external validation: 42.8% vs. 37.8%). CONCLUSION: The BPNN model shows promise for predicting the warfarin maintenance dose after heart valve replacement.

7.
J Nucl Med Technol ; 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31604891

RESUMO

Intro: Coronary artery disease is the leading cause for morbidity and mortality. Tools have been developed to accurately diagnose and evaluate coronary artery disease. Coronary computed tomographic angiography (CCTA) scans provide detailed imaging along with analysis to in order to deliver precise analysis and prognostic information. We sought to evaluate the radiation doses of the 256 detector CT scanner to a 64 slice scanner across a similar profile of patients. Methods: Consecutive patients were screened, enrolled, and consented for the Converge Registry study, in accordance with the Institutional Review Board (IRB) approved protocol. 110 patients underwent CCTA using the GE Revolution 256 detector CT scanner. We matched patients by age, gender and body mass index (BMI) who underwent 64 slice CT scanning. Results: We compared 110 patients in each group. We found that mean dose length product (DLP, presented also in the tables below in millisieverts (mSv)) was significantly lower in the Revolution 256 detector group compared to the 64 slice control group (p<0.05). The radiation dose was reduced 32% with use of Revolution 256 detector scanner for BMI between 18.5 and 24.9 (DLP = 111.2 vs 76.1; 1.56 vs 1.07 mSv; p<0.05). For each BMI subgroup, there was a significant decrease in dose. Regression analysis found that with the increase in BMI both scanners experienced a significant increase in DLP. Conclusion: We are able to demonstrate that the 256 slice CT scanner is able to provide CCTA scans at significantly lower radiation doses compared to the 64 row scanner at different BMI groups, with all other variables accounted for. Lower radiation exposures along with lower contrast requirements can provide quality imaging with high diagnostic accuracy and less risk to the patient.

9.
Am J Hum Genet ; 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31587868

RESUMO

NKAP is a ubiquitously expressed nucleoplasmic protein that is currently known as a transcriptional regulatory molecule via its interaction with HDAC3 and spliceosomal proteins. Here, we report a disorder of transcriptional regulation due to missense mutations in the X chromosome gene, NKAP. These mutations are clustered in the C-terminal region of NKAP where NKAP interacts with HDAC3 and post-catalytic spliceosomal complex proteins. Consistent with a role for the C-terminal region of NKAP in embryogenesis, nkap mutant zebrafish with a C-terminally truncated NKAP demonstrate severe developmental defects. The clinical features of affected individuals are highly conserved and include developmental delay, hypotonia, joint contractures, behavioral abnormalities, Marfanoid habitus, and scoliosis. In affected cases, transcriptome analysis revealed the presence of a unique transcriptome signature, which is characterized by the downregulation of long genes with higher exon numbers. These observations indicate the critical role of NKAP in transcriptional regulation and demonstrate that perturbations of the C-terminal region lead to developmental defects in both humans and zebrafish.

10.
ACS Appl Mater Interfaces ; 11(42): 39369-39375, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31603641

RESUMO

Current-induced spin-orbit torques (SOTs) enable efficient electrical manipulation of the magnetization in heterostructures with a perpendicular magnetic anisotropy through the Rashba effect or spin-Hall effect. However, in conventional SOT-based heterostructures, an in-plane bias magnetic field along the current direction is required for the deterministic switching. Here, we report that the field-free SOT switching can be achieved by introducing a wedged oxide interface between a heavy metal and a ferromagnet. The results demonstrate that the field-free SOT switching is determined by a current-induced perpendicular effective field (Hzeff) originating from the interfacial Rashba effect due to the lateral structural symmetry-breaking introduced by the wedged oxide layer. Furthermore, we show that the sign and magnitude of Hzeff exhibit a significant dependence on the interfacial oxygen content, which can be controlled by the inserted oxide thickness. Our findings provide a deeper insight into the field-free SOT switching by the interfacial Rashba effect.

11.
Diabetes Ther ; 2019 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-31654346

RESUMO

INTRODUCTION: Gestational diabetes mellitus (GDM) is a gestational complication that affects maternal and child health. The placenta provides the fetus with the necessary nutrition and oxygen and takes away the metabolic waste. Patients with GDM are diagnosed and treated merely on the basis of the blood glucose level; this approach does nothing to help evaluate the status of the placenta, which is worth noting in GDM. The purpose of this research was to clarify the relation between thioredoxin-interacting protein (TXNIP) and reactive oxygen species (ROS) in the placenta of patients with GDM, which has thus far remained unclear. METHODS: The expression of TXNIP in the placentas of 10 patients with GDM and 10 healthy puerperae (control group) was investigated via immunofluorescence. The relation among TXNIP, ROS, and the function of mitochondria was explored in HTR-8/SVneo cells stimulated by high glucose (HG). RESULTS: The results showed the expression of TXNIP in the placentas of patients with GDM was higher than that in the control group, and the expression of TXNIP in HTR-8/SVneo cells treated with HG was higher than that in the control group, causing the accumulation of ROS and changes of mitochondria, promoting apoptosis and inhibition of migration. CONCLUSIONS: High expression of TXNIP caused by HG mediates the increasing ROS and the mitochondria dysfunction in GDM; this impairs the function of the placenta and is the basis for the prediction of perinatal outcome.

13.
Protein Pept Lett ; 26(10): 751-757, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31618170

RESUMO

BACKGROUND: NMAAP1 plays a role in regulating macrophage differentiation to the M1 type and exerting antitumoral functions. It is not clear what role and mechanism NMAAP1 does play in the reversal of macrophages from M1 to M2. METHODS: We detected the typing of macrophages with high or low expression of NMAAP1 by QPCR and ELISA, and detected the colocalization of NMAAP1 and endogenous IP3R by laser confocal microscopy, and detected the protein expression in cells by Western-blotting. RESULTS: Our study found that knockdown NMAAP1 in RAW264.7 cells induced macrophage polarization to the M2 type and up-regulation of NMAAP1 in RAW264.7 cells maintain M1 Phenotype even in the presence of IL-4, a stronger inducer of the M2 type. Additionally, Coimmunoprecipitation revealed a protein-protein interaction between NMAAP1 and IP3R and then activates key molecules in the PKC-dependent Raf/MEK/ERK and Ca2+/CaM/CaMKII signaling pathways. Activation of PKC (Thr638/641), ERK1/2 (Thr202/Tyr204) and CaMKII (Thr286) is involved in the regulation of cell differentiation. CONCLUSION: NMAAP1 interacts with IP3R, which in turn activates the PKC-dependent Raf/MEK/ERK and Ca2+/CaM/CaMKII signaling pathways. These results provide a new explanation of the mechanism underlying M1 differentiation.

14.
PLoS One ; 14(10): e0224038, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31644545

RESUMO

Spathiphyllum is a very important tropical plant used as a small, potted, ornamental plant in South China, with an annual output value of hundreds of millions of yuan. In this study, we sequenced and analyzed the complete nucleotide sequence of the Spathiphyllum 'Parrish' chloroplast genome. The whole chloroplast genome is 168,493 bp in length, and includes a pair of inverted repeat (IR) regions (IRa and IRb, each 31,600 bp), separated by a small single-copy (SSC, 15,799 bp) region and a large single-copy (LSC, 89,494 bp) region. Our annotation revealed that the S. 'Parrish' chloroplast genome contained 132 genes, including 87 protein coding genes, 37 transfer RNA genes, and 8 ribosomal RNA genes. In the repeat structure analysis, we detected 281 simple sequence repeats (SSRs) which included mononucleotides (223), dinucleotides (28), trinucleotides (12), tetranucleotides (11), pentanucleotides (6), and hexanucleotides (1), in the S. 'Parrish' chloroplast genome. In addition, we identified 50 long repeats, comprising 18 forward repeats, 13 reverse repeats, 17 palindromic repeats, and 2 complementary repeats. Single nucleotide polymorphism (SNP) and insertion/deletion (indel) analyses of the chloroplast genome of the S. 'Parrish' relative S. cannifolium revealed 962 SNPs in S. 'Parrish'. There were 158 indels (90 insertions and 68 deletions) in the S. 'Parrish' chloroplast genome relative to the S. cannifolium chloroplast genome. Phylogenetic analysis of five species found S. 'Parrish' to be more closely related to S. kochii than to S. cannifolium. This study identified the characteristics of the S. 'Parrish' chloroplast genome, which will facilitate species identification and phylogenetic analysis within the genus Spathiphyllum.

15.
Hemoglobin ; : 1-4, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31645145

RESUMO

In this study, we report on a compound heterozygote for variants in the key erythroid transcription factor Krüppel-like factor 1 (KLF1) gene in a patient who presented with severe, transfusion-dependent hemolytic anemia. The red cells were normochromic and normocytic, and resembled those seen in patients with congenital nonspherocytic hemolytic anemia (CNSHA). Next generation sequencing (NGS) revealed that the patient was a compound heterozygote for the KLF1 frameshift variant c.519_525dup (p.Gly176ArgfsTer179) and a missense variant c.1012C>A (p.Pro338Thr). This report adds to the wide clinical spectrum of KLF1 gene variants. We suggest that loss of KLF1 should be considered in otherwise unexplained cases of congenital hemolytic anemia.

17.
Science ; 365(6460): 1418-1424, 2019 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-31604269

RESUMO

Thermoelectric technology allows conversion between heat and electricity. Many good thermoelectric materials contain rare or toxic elements, so developing low-cost and high-performance thermoelectric materials is warranted. Here, we report the temperature-dependent interplay of three separate electronic bands in hole-doped tin sulfide (SnS) crystals. This behavior leads to synergistic optimization between effective mass (m*) and carrier mobility (µ) and can be boosted through introducing selenium (Se). This enhanced the power factor from ~30 to ~53 microwatts per centimeter per square kelvin (µW cm-1 K-2 at 300 K), while lowering the thermal conductivity after Se alloying. As a result, we obtained a maximum figure of merit ZT (ZT max) of ~1.6 at 873 K and an average ZT (ZT ave) of ~1.25 at 300 to 873 K in SnS0.91Se0.09 crystals. Our strategy for band manipulation offers a different route for optimizing thermoelectric performance. The high-performance SnS crystals represent an important step toward low-cost, Earth-abundant, and environmentally friendly thermoelectrics.

18.
Cell Death Dis ; 10(10): 744, 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31582720

RESUMO

We investigated the mechanism underlying the effect of a combination treatment of 125I radioactive seed implantation and lobaplatin (LBP) in hepatocellular carcinoma. The effects of administration of HCC cells and subcutaneous tumor model of mice with different doses of 125I or a sensitizing concentration of LBP alone, or in combination, on cellular apoptosis and proliferation were analyzed and it was confirmed that LBP promotes 125I-induced apoptosis and inhibition of proliferation of HCC. Furthermore, isobaric tag for relative and absolute quantification labeling analyses suggested that 125I promoted the apoptosis and inhibition of proliferation of HCC cells by upregulating the expression of PERK-eIF2α-ATF4-CHOP pathway, a well-known apoptosis-related pathway. Moreover, LBP was found to boost the 125I-induced upregulation of this pathway and increase the apoptosis. Our data indicate that LBP promotes the apoptotic and anti-proliferative effects of 125I and provide a firm foundation for better clinical application of this combination therapy.

19.
Eur J Med Chem ; 183: 111731, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31577977

RESUMO

With the expectation to find out new anti-gastric cancer agents with high efficacy and selectivity, a series of novel tertiary sulfonamide derivatives were synthesized and the anti-cancer activity was studied in three selected cancer cell lines (MGC-803, PC-3, MCF-7) in vitro. Some of the synthesized compounds could significantly inhibit the proliferation of these tested cancer cells and were more potent than the positive control (5-Fu). The structure-activity relationship of tertiary sulfonamide derivatives was explored in this report. Among the tested compounds, compound 13g containing benzimidazole moiety showed the best anti-proliferation activities against MGC-803 cells (IC50 = 1.02 µM), HGC-27 cells (IC50 = 1.61 µM), SGC-7901 (IC50 = 2.30 µM) cells as well as the good selectivity between the cancer and normal cells. Cellular mechanism studies elucidated compound 13g inhibited the colony formation of gastric cancer cell lines. Meanwhile, compound 13g arrested cell cycle at G2/M phase and induced cell apoptosis. Mechanistically, compound 13g markedly decreased p-Akt and p-c-Raf expression, which revealed that compound 13g targeted gastric cancer cell lines via interfering with AKT/mTOR and RAS/Raf/MEK/ERK pathways. All the findings suggest that compound 13g might be a valuable lead compound for the anti-gastric cancer agents.

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