47 research outputs found

    The effect of friction behavior on the migration of metal elements from stainless-steel articles for food contact

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    Objective To evaluate the effect of friction behavior on migration levels of metal elements from stainless-steel articles for food contact. Methods The migration levels of metal elements from used and new stainless-steel articles were compared according to GB 4806.9-2016 and Council of Europe Resolution CM/Res (2013) 9. The migration conditions were boiling in 4% acetic acid for 30 min followed by at room temperature for 24 h and soaking in 5 g/L citric acid at 100 ℃ for 2 h, respectively. Meanwhile, the impact of dynamic friction on migration were investigated on new stainless-steel articles, where the friction method were referred to the GB/T 32095.2-2015 standard. Migration of metal elements complied with the corresponding standard. Results Based on the European standard, migration of lead in the first migration test was above limit of quantitation (LOQ) in all five used stainless-steel articles after friction, but none in new ones. The quantification rate of chromium in the first migration test in 80% (4/5) of used stainless-steel articles were above LOQ after friction by GB 4806.9-2016 standard while were 20% (1/5) in new ones. The migration level of Cr was higher by GB 4806.9-2016 standard than by European resolution in single dynamic friction study. Results from the dynamic friction experiments indicated that the migration of Cr and Ni reached equilibrium after 3 times of friction. Conclusion The migration condition in GB 4806.9-2016 standard had stronger leaching ability for Cr from stainless-steel articles than that in European resolution. Friction behavior promoted corrosion and metal element migration of stainless steel. Long-term used stainless-steel products had higher lead and chromium migration than new products, but without safety risks

    The potential biomarkers in predicting pathologic response of breast cancer to three different chemotherapy regimens: a case control study

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    <p>Abstract</p> <p>Background</p> <p>Preoperative chemotherapy (PCT) has become the standard of care in locally advanced breast cancer. The identification of patient-specific tumor characteristics that can improve the ability to predict response to therapy would help optimize treatment, improve treatment outcomes, and avoid unnecessary exposure to potential toxicities. This study is to determine whether selected biomarkers could predict pathologic response (PR) of breast tumors to three different PCT regimens, and to identify a subset of patients who would benefit from a given type of treatment.</p> <p>Methods</p> <p>118 patients with primary breast tumor were identified and three PCT regimens including DEC (docetaxel+epirubicin+cyclophosphamide), VFC (vinorelbine/vincristine+5-fluorouracil+cyclophosphamide) and EFC (epirubicin+5-fluorouracil+cyclophosphamide) were investigated. Expression of steroid receptors, HER2, P-gp, MRP, GST-pi and Topo-II was evaluated by immunohistochemical scoring on tumor tissues obtained before and after PCT. The PR of breast carcinoma was graded according to Sataloff's classification. Chi square test, logistic regression and Cochran-Mantel-Haenszel assay were performed to determine the association between biomarkers and PR, as well as the effectiveness of each regimen on induction of PR.</p> <p>Results</p> <p>There was a clear-cut correlation between the expression of ER and decreased PR to PCT in all three different regimens (<it>p </it>< 0.05). HER2 expression is significantly associated with increased PR in DEC regimen (<it>p </it>< 0.05), but not predictive for PR in EFC and VFC groups. No significant correlation was found between biomarkers PgR, Topo-II, P-gp, MRP or GST-pi and PR to any tested PCT regimen. After adjusted by a stratification variable of ER or HER2, DEC regimen was more effective in inducing PR in comparison with VFC and EFC regimens.</p> <p>Conclusion</p> <p>ER is an independent predictive factor for PR to PCT regimens including DEC, VFC and EFC in primary breast tumors, while HER2 is only predictive for DEC regimen. Expression of PgR, Topo-II, P-gp, MRP and GST-pi are not predictive for PR to any PCT regimens investigated. Results obtained in this clinical study may be helpful for the selection of appropriate treatments for breast cancer patients.</p

    Broadening of Neutralization Activity to Directly Block a Dominant Antibody-Driven SARS-Coronavirus Evolution Pathway

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    Phylogenetic analyses have provided strong evidence that amino acid changes in spike (S) protein of animal and human SARS coronaviruses (SARS-CoVs) during and between two zoonotic transfers (2002/03 and 2003/04) are the result of positive selection. While several studies support that some amino acid changes between animal and human viruses are the result of inter-species adaptation, the role of neutralizing antibodies (nAbs) in driving SARS-CoV evolution, particularly during intra-species transmission, is unknown. A detailed examination of SARS-CoV infected animal and human convalescent sera could provide evidence of nAb pressure which, if found, may lead to strategies to effectively block virus evolution pathways by broadening the activity of nAbs. Here we show, by focusing on a dominant neutralization epitope, that contemporaneous- and cross-strain nAb responses against SARS-CoV spike protein exist during natural infection. In vitro immune pressure on this epitope using 2002/03 strain-specific nAb 80R recapitulated a dominant escape mutation that was present in all 2003/04 animal and human viruses. Strategies to block this nAb escape/naturally occurring evolution pathway by generating broad nAbs (BnAbs) with activity against 80R escape mutants and both 2002/03 and 2003/04 strains were explored. Structure-based amino acid changes in an activation-induced cytidine deaminase (AID) “hot spot” in a light chain CDR (complementarity determining region) alone, introduced through shuffling of naturally occurring non-immune human VL chain repertoire or by targeted mutagenesis, were successful in generating these BnAbs. These results demonstrate that nAb-mediated immune pressure is likely a driving force for positive selection during intra-species transmission of SARS-CoV. Somatic hypermutation (SHM) of a single VL CDR can markedly broaden the activity of a strain-specific nAb. The strategies investigated in this study, in particular the use of structural information in combination of chain-shuffling as well as hot-spot CDR mutagenesis, can be exploited to broaden neutralization activity, to improve anti-viral nAb therapies, and directly manipulate virus evolution

    Metabolomics reveals significant variations in metabolites and correlations regarding the maturation of walnuts (Juglans regia L.)

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    The content of walnut metabolites is related to its nutritive value and physiological characteristics, however, comprehensive information concerning the metabolome of walnut kernels is limited. In this study we analyzed the metabolites of walnut kernels at five developmental stages from filling to ripening using GC-MS-based untargeted metabolomics; of a total 252 peaks identified, 85 metabolites were positively identified. Further statistical analysis revealed that these 85 metabolites covered different types of metabolism pathways. PCA scores revealed that the metabolic compositions of the embryo are different at each stage, while the metabolic composition of the endotesta could not be significantly separated into distinct groups. Additionally, 7225 metabolite-metabolite correlations were detected in walnut kernel by a Pearson correlation coefficient approach; during screening of the calculated correlations, 463 and 1047 were determined to be significant with r2≥0.49 and had a false discovery rate (FDR) ≤0.05 in endotesta and embryo, respectively. This work provides the first comprehensive metabolomic study of walnut kernels and reveals that most of the carbohydrate and protein-derived carbon was transferred into other compounds, such as fatty acids, during the maturation of walnuts, which may potentially provide the basis for further studies on walnut kernel metabolism

    Phosphorus mobilization and improvement of crop agronomic performances by a new white‐rot fungus Ceriporia lacerata HG2011

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    BACKGROUND: Some soil microorganisms can mobilize unavailable phosphorus (P) in soils for plant use and increase P fertilizer efficiency. Thus, an abiotic P solubilization experiment and fungal incubation in solution and soil were conducted to investigate the mobilization of various P compounds by a new white-rot fungus Ceriporia lacerata HG2011. The crop agronomic performances were then evaluated in the winter barley–summer maize–winter wheat rotation field. RESULTS: Ceriporia lacerata HG2011 had a wide P mobilization spectrum and mobilized P by different mechanisms depending on P sources supplied in liquid culture. The chief mechanism employed by this fungus was the production of protons in mobilizing Ca 3(PO 4) 2, low-molecular-weight organic acids and other unknown substances in FePO 4 and AlPO 4, phytase (an inducible enzyme in the presence of phytate) in phytate, and phosphatase in lecithin and ribonucleic acid, respectively. As a result of the large fungal biomass, P accumulated in the hypha should also be considered in the assessment of the fungal P mobilization, and not just only soluble inorganic P. As C. lacerata HG2011 colonized on and in the test soil, phosphatase and phytase activities were enhanced but pH decreased in the soil, leading to P mobilization. The application of this fungus mobilized soil P, increased crop P uptake and yields, and consecutively reduced P fertilizer use without yield sacrifices in the multiple crop rotation field. CONCLUSION: C. lacerata HG2011 showed a new use with respect to mobilizing soil P and reducing P fertilizer input in modern agriculture beyond medical purposes, environmental protection and biofuel production

    Phosphorus mobilization and improvement of crop agronomic performances by a new white‐rot fungus Ceriporia lacerata HG2011

    No full text
    BACKGROUND: Some soil microorganisms can mobilize unavailable phosphorus (P) in soils for plant use and increase P fertilizer efficiency. Thus, an abiotic P solubilization experiment and fungal incubation in solution and soil were conducted to investigate the mobilization of various P compounds by a new white-rot fungus Ceriporia lacerata HG2011. The crop agronomic performances were then evaluated in the winter barley–summer maize–winter wheat rotation field. RESULTS: Ceriporia lacerata HG2011 had a wide P mobilization spectrum and mobilized P by different mechanisms depending on P sources supplied in liquid culture. The chief mechanism employed by this fungus was the production of protons in mobilizing Ca 3(PO 4) 2, low-molecular-weight organic acids and other unknown substances in FePO 4 and AlPO 4, phytase (an inducible enzyme in the presence of phytate) in phytate, and phosphatase in lecithin and ribonucleic acid, respectively. As a result of the large fungal biomass, P accumulated in the hypha should also be considered in the assessment of the fungal P mobilization, and not just only soluble inorganic P. As C. lacerata HG2011 colonized on and in the test soil, phosphatase and phytase activities were enhanced but pH decreased in the soil, leading to P mobilization. The application of this fungus mobilized soil P, increased crop P uptake and yields, and consecutively reduced P fertilizer use without yield sacrifices in the multiple crop rotation field. CONCLUSION: C. lacerata HG2011 showed a new use with respect to mobilizing soil P and reducing P fertilizer input in modern agriculture beyond medical purposes, environmental protection and biofuel production

    Phosphorus mobilization and improvement of crop agronomic performances by a new white‐rot fungus Ceriporia lacerata HG2011

    No full text
    BACKGROUND: Some soil microorganisms can mobilize unavailable phosphorus (P) in soils for plant use and increase P fertilizer efficiency. Thus, an abiotic P solubilization experiment and fungal incubation in solution and soil were conducted to investigate the mobilization of various P compounds by a new white-rot fungus Ceriporia lacerata HG2011. The crop agronomic performances were then evaluated in the winter barley–summer maize–winter wheat rotation field. RESULTS: Ceriporia lacerata HG2011 had a wide P mobilization spectrum and mobilized P by different mechanisms depending on P sources supplied in liquid culture. The chief mechanism employed by this fungus was the production of protons in mobilizing Ca 3(PO 4) 2, low-molecular-weight organic acids and other unknown substances in FePO 4 and AlPO 4, phytase (an inducible enzyme in the presence of phytate) in phytate, and phosphatase in lecithin and ribonucleic acid, respectively. As a result of the large fungal biomass, P accumulated in the hypha should also be considered in the assessment of the fungal P mobilization, and not just only soluble inorganic P. As C. lacerata HG2011 colonized on and in the test soil, phosphatase and phytase activities were enhanced but pH decreased in the soil, leading to P mobilization. The application of this fungus mobilized soil P, increased crop P uptake and yields, and consecutively reduced P fertilizer use without yield sacrifices in the multiple crop rotation field. CONCLUSION: C. lacerata HG2011 showed a new use with respect to mobilizing soil P and reducing P fertilizer input in modern agriculture beyond medical purposes, environmental protection and biofuel production

    A new function of white-rot fungi Ceriporia lacerata HG2011: improvement of biological nitrogen fixation of broad bean (Vicia faba)

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    The inoculation of plant growth-promoting microbes with multifarious functions is a simple, economic, and effective way to improve nodulation and biological nitrogen fixation (BNF) of legumes. Broad bean (Vicia faba) is commonly grown in the winter in tropics and subtropics for increasing soil N and farmers’ income. The new functions of Ceriporia lacerata HG2011, a white-rot fungus, in nodulation and BNF (measured by 15N natural abundance) were studied with the broad bean in liquid culture, soil incubation, and greenhouse pot experiments. The results showed that this fungus released IAA, GA, and Fe-binding ligands into culture solutions, increased lateral roots and root surfaces, and mobilized phosphorus and iron into bioavailable forms in the soil. These performances may be beneficial to nodulation and BNF. The indigenous rhizobia that infect broad been were long-lived in the experimental soil. The efficiency of exogenous rhizobium inoculation may be unsatisfactory in the soils for frequently growing broad beans because of fierce competition with native rhizobia. Compared with no inoculation, the fungal inoculant increased nutrient (nitrogen, phosphorus, and potassium) availability in the fertilized soil, nodule mass, and plant BNF and nutrient uptake, leading to higher plant biomass and grain yield. Thus, C. lacerata HG2011 provided more potential sites for rhizobia infection in nodulation, increased nodule size, and improved nodule mineral nutrient (particularly phosphorus and iron) and photosynthate acquisitions, resulting in better nodulation and increased plant BNF. These significant findings firstly proved a new function of C. lacerata HG2011 in improving the inoculation and BNF of legume plants

    A new function of white-rot fungi Ceriporia lacerata HG2011: improvement of biological nitrogen fixation of broad bean (Vicia faba)

    No full text
    The inoculation of plant growth-promoting microbes with multifarious functions is a simple, economic, and effective way to improve nodulation and biological nitrogen fixation (BNF) of legumes. Broad bean (Vicia faba) is commonly grown in the winter in tropics and subtropics for increasing soil N and farmers’ income. The new functions of Ceriporia lacerata HG2011, a white-rot fungus, in nodulation and BNF (measured by 15N natural abundance) were studied with the broad bean in liquid culture, soil incubation, and greenhouse pot experiments. The results showed that this fungus released IAA, GA, and Fe-binding ligands into culture solutions, increased lateral roots and root surfaces, and mobilized phosphorus and iron into bioavailable forms in the soil. These performances may be beneficial to nodulation and BNF. The indigenous rhizobia that infect broad been were long-lived in the experimental soil. The efficiency of exogenous rhizobium inoculation may be unsatisfactory in the soils for frequently growing broad beans because of fierce competition with native rhizobia. Compared with no inoculation, the fungal inoculant increased nutrient (nitrogen, phosphorus, and potassium) availability in the fertilized soil, nodule mass, and plant BNF and nutrient uptake, leading to higher plant biomass and grain yield. Thus, C. lacerata HG2011 provided more potential sites for rhizobia infection in nodulation, increased nodule size, and improved nodule mineral nutrient (particularly phosphorus and iron) and photosynthate acquisitions, resulting in better nodulation and increased plant BNF. These significant findings firstly proved a new function of C. lacerata HG2011 in improving the inoculation and BNF of legume plants

    Investigation of Micro Square Structure Fabrication by Applying Textured Cutting Tool in WEDM

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    This paper studies micro structure fabrication by means of a textured tool cutting edge, which is manufactured by applying the wire cut electrical discharge machining (WEDM). Machining performance of the square structure fabrication on the tool cutting edge is investigated in the WEDM process, and the machining accuracy is explored in experimental analyses. In this proposed method, undesired overcut comes from the discharge between the processing debris and the side wall of the target structure. Furthermore, by applying the textured cutting tool, the target square structure is directly fabricated on the alumina workpiece with just a simple turning process, which verifies the feasibility of the proposed tool cutting edge textured method by applying the WEDM. This technology is expected to become a potential method for the mass production of micro structure surfaces in the future
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