An easy and rapid method is proposed for the determination of PCBs in automotive shredder residues, using gas chromatography combined with low resolution mass spectrometry (GC-MS). It is based on direct n-hexane solid...An easy and rapid method is proposed for the determination of PCBs in automotive shredder residues, using gas chromatography combined with low resolution mass spectrometry (GC-MS). It is based on direct n-hexane solid-liquid extraction, subtracting background of the lineal aliphatic hydrocarbon interferences and integration of chromatographic peaks containing selected ion PCBs masses (256, 292 and 326 m/z), which are common in all PCBs formulations. Recoveries were in the 80% - 120% range;PCBs were detected and quantified in shredder samples from an automotive shredder industry, thus indicating the validity of the method.展开更多
Colorectal adenocarcinoma （CRC） is the third most common type of cancer and the fourth most frequent cause of death due to cancer worldwide. Given the natural history of CRC, early diagnosis appears to be the most a...Colorectal adenocarcinoma （CRC） is the third most common type of cancer and the fourth most frequent cause of death due to cancer worldwide. Given the natural history of CRC, early diagnosis appears to be the most appropriate tool to reduce disease-related mortality. A field of recent interest is clinical proteomics, which was reported to lead to high sensitivity and specificities for early detection of several solid tumors. This emerging field uses mass spectrometry-based protein profiles/patterns of easy accessible body fluids to distinguish cancer from non-cancer patients. These discrepancies may be a result of： （i） proteins being abnormally produced or shed and added to the serum proteome, （2） proteins clipped or modified as a consequence of the disease process, or （3） proteins subtracted from the proteome owing to disease-related proteolytic degradation pathways. Therefore, protein pattern diagnostics would provide easy and reliable tools for detection of cancer. This paper focuses on the current status of clinical proteomics research in oncology and in colorectal cancer especially, and will reflect on pitfalls and fears in this relatively new area of clinical medicine, which are reproducibility issues and pre-analytical factors, statistical issues, and identification and nature of discriminating proteins/peptides.展开更多
The Kuril islands constitute a volcanic island arc-trench system, stretching from eastern Hokkaido （Japan） to Kamchatka （Russia） along the northwestern Pacific subduction system, The current arc consists of severa...The Kuril islands constitute a volcanic island arc-trench system, stretching from eastern Hokkaido （Japan） to Kamchatka （Russia） along the northwestern Pacific subduction system, The current arc consists of several volcanic islands mainly with Neogene basement and capped by several, predominantly andesitic, active subduction stratovolcanoes, Kunashir Island is the southwestern-most island of the arc, just off the Hokkaido coast and represents the study area in this paper. The island is composed of a Lower Complex of mainly late Miocene to Pliocene volcanic rocks, covered by an Upper Complex of younger （basaltic） andesitic lava flows and tuffs on which currently four active volcanic edifices are built. In the Lower Complex sub-volcanic and deeper-seated intrusives of the so-called Prasolov and Dokuchaev magmatic complexes are found, More differentiated, tonalitic-granodioritic rocks were collected from these small intrusive bodies. An early Oligocene zircon LA-ICP-MS U/Pb age of 31 Ma for the Prasolov Complex was obtained, showing that the basement of Kunashir Island is older than previously thought. Thermochronometry （apatite fission-track and U-Th-Sm/He and zircon U-ThJHe analyses） further shows that the magmatic basement of the island was rapidly exhumed in the Pleistocene to present levels in a differential pattern, with He-ages ranging from 1.9 to 0.8 Ma. It is shown that the northern section of the island was hereby exhumed more intensely.展开更多
A new SPME/HPLC interface is developed. It is based on thermal desorption from the SPME fiber and organic solvent collection of the desorbed analytes by sweeping them with an argon flow into a small organic solvent vo...A new SPME/HPLC interface is developed. It is based on thermal desorption from the SPME fiber and organic solvent collection of the desorbed analytes by sweeping them with an argon flow into a small organic solvent volume which is further injected into the HPLC chromatograph. Extraction and desorption parameters were investigated using five PAHs of different volatilities (naphthalene, acenaphthalene, fluorene, phenanthrene and anthracene) as test compounds and fluorimetric detection. Regression coefficients closed to 0.99 with RDS = 3) and detection limits in the range 0.07 - 0.99 μg.L-1 were found. A method was applied to determine the above PAHs in water samples. The results were compared with those supplied by the 550.1 EPA method showing the agreement of both methods at the 0.05 significance level.展开更多
Oleanolic acid(OA)and ursolic acid(UA)are isomeric tritcrpenes that are difficult to separate chromatographically.Studies have indicated that both OA and UA have antifertility properties in several livestock species,s...Oleanolic acid(OA)and ursolic acid(UA)are isomeric tritcrpenes that are difficult to separate chromatographically.Studies have indicated that both OA and UA have antifertility properties in several livestock species,suppressing attainment of puberty,gonad function and gamete production.Being able to determine the presence and quantity of the OA and UA in moringa and pawpaw seeds will allow for calculation of optimal inclusion levels of these acids in animal diets for antifertility-activity.The purpose of the study was thus to quantify the levels of OA and UA in Moringa and pawpaw seed powder by means of ultra-high performance liquid chromatography with electrospray ionization tandem mass spectrometry(UHPLC-ESI-MS/MS).Only OA was detected in moringa seeds at a concentration level of 0.508 p.g/g+0.032 pg/g dry weight.UA and OA could not be detected in pawpaw seeds used in this study.The presence of OA in moringa seeds suggest that the seeds can be included in tilapia diets as a potential antifertility treatment to control precocious breeding in tilapia culture in small scale farming systems in Sub-Saharan Africa.Further studies are warranted to determine the levels of OA and UA composition in moringa seeds from other parts of the Sub-Saharan Africa(other than Zambia).展开更多
Phosphoglycerate dehydrogenase(PHGDH)has emerged as a crucial factor in macromolecule synthesis,neutralizing oxidative stress,and regulating methylation reactions in cancer cells,lymphocytes,and endothelial cells.Howe...Phosphoglycerate dehydrogenase(PHGDH)has emerged as a crucial factor in macromolecule synthesis,neutralizing oxidative stress,and regulating methylation reactions in cancer cells,lymphocytes,and endothelial cells.However,the role of PHGDH in tumor-associated macrophages(TAMs)is poorly understood.Here,we found that the T helper 2(Th2)cytokine interleukin-4 and tumor-conditioned media upregulate the expression of PHGDH in macrophages and promote immunosuppressive M2 macrophage activation and proliferation.Loss of PHGDH disrupts cellular metabolism and mitochondrial respiration,which are essential for immunosuppressive macrophages.Mechanistically,PHGDH-mediated serine biosynthesis promotesα-ketoglutarate production,which activates mTORC1 signaling and contributes to the maintenance of an M2-like macrophage phenotype in the tumor microenvironment.Genetic ablation of PHGDH in macrophages from tumor-bearing mice results in attenuated tumor growth,reduced TAM infiltration,a phenotypic shift of M2-like TAMs toward an M1-like phenotype,downregulated PD-L1 expression and enhanced antitumor T-cell immunity.Our study provides a strong basis for further exploration of PHGDH as a potential target to counteract TAM-mediated immunosuppression and hinder tumor progression.展开更多
Stress Knowledge Map(SKM;https://skm.nib.si)is a publicly available resource containing two complementary knowledge graphs that describe the current knowledge of biochemical,signaling,and regulatory molecular interact...Stress Knowledge Map(SKM;https://skm.nib.si)is a publicly available resource containing two complementary knowledge graphs that describe the current knowledge of biochemical,signaling,and regulatory molecular interactions in plants:a highly curated model of plant stress signaling(PSS;543 reactions)and a large comprehensive knowledge network(488390 interactions).Both were constructed by domain experts through systematic curation of diverse literature and database resources.SKM provides a single entry point for investigations of plant stress response and related growth trade-offs,as well as interactive explorations of current knowledge.PSS is also formulated as a qualitative and quantitative model for systems biology and thus represents a starting point for a plant digital twin.Here,we describe the features of SKM and show,through two case studies,how it can be used for complex analyses,including systematic hypothesis generation and design of validation experiments,or to gain new insights into experimental observations in plant biology.展开更多
文摘An easy and rapid method is proposed for the determination of PCBs in automotive shredder residues, using gas chromatography combined with low resolution mass spectrometry (GC-MS). It is based on direct n-hexane solid-liquid extraction, subtracting background of the lineal aliphatic hydrocarbon interferences and integration of chromatographic peaks containing selected ion PCBs masses (256, 292 and 326 m/z), which are common in all PCBs formulations. Recoveries were in the 80% - 120% range;PCBs were detected and quantified in shredder samples from an automotive shredder industry, thus indicating the validity of the method.
文摘Colorectal adenocarcinoma （CRC） is the third most common type of cancer and the fourth most frequent cause of death due to cancer worldwide. Given the natural history of CRC, early diagnosis appears to be the most appropriate tool to reduce disease-related mortality. A field of recent interest is clinical proteomics, which was reported to lead to high sensitivity and specificities for early detection of several solid tumors. This emerging field uses mass spectrometry-based protein profiles/patterns of easy accessible body fluids to distinguish cancer from non-cancer patients. These discrepancies may be a result of： （i） proteins being abnormally produced or shed and added to the serum proteome, （2） proteins clipped or modified as a consequence of the disease process, or （3） proteins subtracted from the proteome owing to disease-related proteolytic degradation pathways. Therefore, protein pattern diagnostics would provide easy and reliable tools for detection of cancer. This paper focuses on the current status of clinical proteomics research in oncology and in colorectal cancer especially, and will reflect on pitfalls and fears in this relatively new area of clinical medicine, which are reproducibility issues and pre-analytical factors, statistical issues, and identification and nature of discriminating proteins/peptides.
基金supported by a start-up grant from the Faculty of Sciences,Ghent University(JDG)and the Australian Research Council(Grant No.DP150101730)
文摘The Kuril islands constitute a volcanic island arc-trench system, stretching from eastern Hokkaido （Japan） to Kamchatka （Russia） along the northwestern Pacific subduction system, The current arc consists of several volcanic islands mainly with Neogene basement and capped by several, predominantly andesitic, active subduction stratovolcanoes, Kunashir Island is the southwestern-most island of the arc, just off the Hokkaido coast and represents the study area in this paper. The island is composed of a Lower Complex of mainly late Miocene to Pliocene volcanic rocks, covered by an Upper Complex of younger （basaltic） andesitic lava flows and tuffs on which currently four active volcanic edifices are built. In the Lower Complex sub-volcanic and deeper-seated intrusives of the so-called Prasolov and Dokuchaev magmatic complexes are found, More differentiated, tonalitic-granodioritic rocks were collected from these small intrusive bodies. An early Oligocene zircon LA-ICP-MS U/Pb age of 31 Ma for the Prasolov Complex was obtained, showing that the basement of Kunashir Island is older than previously thought. Thermochronometry （apatite fission-track and U-Th-Sm/He and zircon U-ThJHe analyses） further shows that the magmatic basement of the island was rapidly exhumed in the Pleistocene to present levels in a differential pattern, with He-ages ranging from 1.9 to 0.8 Ma. It is shown that the northern section of the island was hereby exhumed more intensely.
文摘A new SPME/HPLC interface is developed. It is based on thermal desorption from the SPME fiber and organic solvent collection of the desorbed analytes by sweeping them with an argon flow into a small organic solvent volume which is further injected into the HPLC chromatograph. Extraction and desorption parameters were investigated using five PAHs of different volatilities (naphthalene, acenaphthalene, fluorene, phenanthrene and anthracene) as test compounds and fluorimetric detection. Regression coefficients closed to 0.99 with RDS = 3) and detection limits in the range 0.07 - 0.99 μg.L-1 were found. A method was applied to determine the above PAHs in water samples. The results were compared with those supplied by the 550.1 EPA method showing the agreement of both methods at the 0.05 significance level.
文摘Oleanolic acid(OA)and ursolic acid(UA)are isomeric tritcrpenes that are difficult to separate chromatographically.Studies have indicated that both OA and UA have antifertility properties in several livestock species,suppressing attainment of puberty,gonad function and gamete production.Being able to determine the presence and quantity of the OA and UA in moringa and pawpaw seeds will allow for calculation of optimal inclusion levels of these acids in animal diets for antifertility-activity.The purpose of the study was thus to quantify the levels of OA and UA in Moringa and pawpaw seed powder by means of ultra-high performance liquid chromatography with electrospray ionization tandem mass spectrometry(UHPLC-ESI-MS/MS).Only OA was detected in moringa seeds at a concentration level of 0.508 p.g/g+0.032 pg/g dry weight.UA and OA could not be detected in pawpaw seeds used in this study.The presence of OA in moringa seeds suggest that the seeds can be included in tilapia diets as a potential antifertility treatment to control precocious breeding in tilapia culture in small scale farming systems in Sub-Saharan Africa.Further studies are warranted to determine the levels of OA and UA composition in moringa seeds from other parts of the Sub-Saharan Africa(other than Zambia).
文摘Phosphoglycerate dehydrogenase(PHGDH)has emerged as a crucial factor in macromolecule synthesis,neutralizing oxidative stress,and regulating methylation reactions in cancer cells,lymphocytes,and endothelial cells.However,the role of PHGDH in tumor-associated macrophages(TAMs)is poorly understood.Here,we found that the T helper 2(Th2)cytokine interleukin-4 and tumor-conditioned media upregulate the expression of PHGDH in macrophages and promote immunosuppressive M2 macrophage activation and proliferation.Loss of PHGDH disrupts cellular metabolism and mitochondrial respiration,which are essential for immunosuppressive macrophages.Mechanistically,PHGDH-mediated serine biosynthesis promotesα-ketoglutarate production,which activates mTORC1 signaling and contributes to the maintenance of an M2-like macrophage phenotype in the tumor microenvironment.Genetic ablation of PHGDH in macrophages from tumor-bearing mice results in attenuated tumor growth,reduced TAM infiltration,a phenotypic shift of M2-like TAMs toward an M1-like phenotype,downregulated PD-L1 expression and enhanced antitumor T-cell immunity.Our study provides a strong basis for further exploration of PHGDH as a potential target to counteract TAM-mediated immunosuppression and hinder tumor progression.
基金funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement 862858(ADAPT)the Slovenian Research Agency under grant agreements 1000-15-0105,Z7-1888,J4-1777,P4-0165,N4-0199,Z4-50146,and J4-3089ELIXIR,the research infrastructure for life science data through the ELIXIR Implementation Study“Increasing plant data findability for ELIXIR and beyond”and ELIXIR-SI.We gratefully acknowledge funding from the Deutsche Forschungsgemeinschaft(DFG)to U.C.V.(INST 217/939-1 FUGG).
文摘Stress Knowledge Map(SKM;https://skm.nib.si)is a publicly available resource containing two complementary knowledge graphs that describe the current knowledge of biochemical,signaling,and regulatory molecular interactions in plants:a highly curated model of plant stress signaling(PSS;543 reactions)and a large comprehensive knowledge network(488390 interactions).Both were constructed by domain experts through systematic curation of diverse literature and database resources.SKM provides a single entry point for investigations of plant stress response and related growth trade-offs,as well as interactive explorations of current knowledge.PSS is also formulated as a qualitative and quantitative model for systems biology and thus represents a starting point for a plant digital twin.Here,we describe the features of SKM and show,through two case studies,how it can be used for complex analyses,including systematic hypothesis generation and design of validation experiments,or to gain new insights into experimental observations in plant biology.
