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111.
Alessandra Bosutti Barbara Dapas Gabriele Grassi Rossana Bussani Fabrizio Zanconati Fabiola Giudici Cristina Bottin Nicola Pavan Carlo Trombetta Bruna Scaggiante 《International journal of molecular sciences》2022,23(8)
Although the eukaryotic elongation factor eEF1A1 plays a role in various tumours, there is little information on its prognosis/therapeutic value in prostate carcinoma. In high-grade and castration-resistant prostate carcinoma (CRPC), the identification of novel therapeutic markers/targets remains a priority. The expression of eEF1A1 protein was determined in formalin-fixed, paraffin-embedded prostate cancer and hyperplasia tissue by IHC. The role of eEF1A1 was investigated in a cellular model using a DNA aptamer (GT75) we previously developed. We used the aggressive CRPC cancer PC-3 and non-tumourigenic PZHPV-7 lines. Cytotoxicity was measured by the MTS assay and eEF1A1 protein levels by in-cell Western assays. The mRNA levels of eEF1A1 were measured by qPCR and ddPCR. Higher expression of eEF1A1 was found in Gleason 7–8 compared with 4–6 tissues (Gleason ≥ 7, 87% versus Gleason ≤ 6, 54%; p = 0.033). Patients with a high expression of eEF1A1 had a worse clinical outcome. In PC-3, but not in PZHPV-7, GT75 decreased cell viability and increased autophagy and cell detachment. In PC-3 cells, but not in PZHPV-7, GT75 mainly co-localised with the fraction of eEF1A1 bound to actin. Overexpression of the eEF1A1 protein can identify aggressive forms of prostate cancer. The targeting of eEF1A1 by GT75 impaired cell viability in PC-3 cancer cells but not in PZHPV-7 non-tumourigenic cells, indicating a specific role for the protein in cancer survival. The eEF1A1–actin complexes appear to be critical for the viability of PC-3 cancer cells, suggesting that eEF1A1 may be an attractive target for therapeutic strategies in advanced forms of prostate cancer. 相似文献
112.
Baffone W Casaroli A Citterio B Pierfelici L Campana R Vittoria E Guaglianone E Donelli G 《International journal of food microbiology》2006,107(1):83-91
Water is known as one of the main transmission routes of Campylobacter and contributes to increase the number of sporadic infections and outbreaks. Campylobacter jejuni persists in the environment, especially in water, in a viable but non-culturable (VBNC) form that is thought to be a possible cause of water-borne outbreaks. In this study, we evaluated the loss of culturability and viability of 9 C. jejuni strains of clinical origin and one ATCC reference strain when kept at 4 degrees C in artificial sea water (ASW). Culturability was measured as colony-forming units while viability was evaluated by CTC-DAPI double staining and the combined CTC-specific fluorescent antibody technique (CTC-FA). When cultured on Columbia Agar plates, strains exhibited different growth profiles which allowed to classify them into three different groups. Both techniques used to monitor the viability of the bacterial cells showed that C. jejuni strains survived in the VBNC form in the microcosms through a period lasting from 138 to 152 days. The recovery of C. jejuni VBNC forms to culturability, as evidenced by cell division, was obtained by passage in the mouse intestine. Our results indicate that C. jejuni VBNC cells were able to remain in this state for a few months and regain their culturability after in vivo passage depending on their lasting in the VBNC state, which affects the number of respiring bacteria. In fact, the resuscitation was achieved when the number of respiring bacteria became higher than 10(4) cell/ml. Therefore, a relatively high microbial titer of respiring bacteria in the VBNC state seems to be important for the resuscitation and subsequent intestinal colonisation. 相似文献
113.
Determination of Iron Species in Samples of Iron-Fortified Food 总被引:1,自引:0,他引:1
Przemyslaw Niedzielski Magdalena Zielinska-Dawidziak Lidia Kozak Pawel Kowalewski Barbara Szlachetka Sylwia Zalicka Weronika Wachowiak 《Food Analytical Methods》2014,7(10):2023-2032
The paper presents the determination of iron forms in food products. The procedure of sample extraction was developed and optimized, preserving the content of particular forms of iron. The colorimetric method using 2,2′-bipirydyl (measurements at 520 nm) was applied in Fe(II) determinations, while in Fe(III) determinations, the colorimetric method with potassium thiocyanate (measurements at 470 nm) was applied. The total content of iron was determined by the technique of atomic absorption spectrometry, which allowed for the determination of iron content in organic and inorganic complex compounds. Detection limits of 1 mg kg?1 were obtained for all determined iron forms, with the precision ranging between 0.7 % and 1.5 % for 10 mg kg?1 concentration. The optimized analytical procedure was applied in the determinations of iron forms in iron-fortified food products. 相似文献
114.
Management of aquatic ecosystems is hampered because current methodology limits characterization of phosphorus (P)forms. We developed a procedure to characterize dissolved (DP) and particulate (PP) P from river waters by solution 31P nuclear magnetic resonance (NMR) spectroscopy, using 4-L samples, and tested this procedure with a spiking trial. Most P was orthophosphate. Organic P forms included phosphonates, myo-inositol hexakisphosphate, and orthophosphate diesters. This research represents an important technical advance to characterize DP and PP in natural waters. It is simple, uses samples small enough for routine collection, and puts PP and DP into the same chemical environment for direct comparison. The technique is sensitive, detecting changes in spectra from P additions as small as 2% of total P, and identifying differences from two points along the flow path of a single river. However, lyophilizing samples in NaOH-ethylenediamine-tetraacetic acid (EDTA) may alter some P forms, which requires further investigation. 相似文献
115.
Enrico Maltini Danila Torreggiani Barbara Rondo Brovetto Gianni Bertolo 《Food research international (Ottawa, Ont.)》1993,26(6):413-419
Fruit pieces of some species have been processed to be used as ingredients in various food systems, either by partial dehydration alone or by osmosis and partial dehydration, to achieve different levels of water activity and solids contents in the final products.
The relationships existing among processing, phase composition after processing and functional properties of the products have been assessed within a useful range of water content and water activity.
The functional properties are expressed as diagrams relating the phase composition (soluble solids, insoluble solids and water) to the range of consistencies obtainable at various water activities. These diagrams provide a useful tool for preparing fruit ingredients suitable for specific food systems. 相似文献
116.
Yiming Ou Lu Pei Keqiang Lai Yiqun Huang Barbara A. Rasco Xiaohui Wang Yuxia Fan 《Food Analytical Methods》2017,10(3):565-574
Sudan dyes are often illegally added as colorants into a variety of foodstuffs and have been tied to many food safety issues. In this study, surface-enhanced Raman spectroscopy (SERS) coupled with Au–Ag core-shell nanospheres (Au@Ag) was applied to analyze standard solutions of Sudan I–IV and Sudan dyes in chili flakes. With the use of 90 ± 5 nm Au@Ag (Au seed 20 ± 2 nm) as SERS substrate, the lowest detectible concentrations for Sudan I and II were 0.10 mg/L, for Sudan III was 0.08 mg/L, and for Sudan IV was 0.2 mg/L. The use of principal component analysis (PCA) could successfully classify different Sudan dyes based upon the SERS spectra of their standard solutions. For chili flakes, the use of acetonitrile as extraction solvent led to an overall higher sensitivity for analysis of Sudan dyes with SERS method compared to that of methanol, ethanol, and n-hexane. The lowest detectible concentrations for Sudan I–III in chili flakes were 1 mg/kg and for Sudan IV was 2 mg/kg, which were about ten times as much as that for their standard solutions due to the interference of non-target compounds from sample matrices. Partial least squares (PLS) models developed for quantitative analyses showed relatively high linear correlation between the actual and predicted amounts of Sudan dyes in chili flakes (R 2 cv = 0.869–0.959). The results showed great potential of applying Au@Ag as SERS substrate for qualitative and quantitative analysis of Sudan I–IV with simplified sample preparation method. 相似文献
117.
Alexander Prange Nils Kühlsen Barbara Birzele Isolde Arzberger Josef Hormes Susanne Antes Peter Köhler 《European Food Research and Technology》2001,212(5):570-575
The sulfur containing gluten proteins largely determine the baking quality of wheat. In order to probe the speciation of sulfur, gluten proteins [gliadin, high molecular weight (HMW) and low molecular weight (LMW) subunits of glutenin], stored glutenin subunits as well as flour were investigated in situ by S K-edge X-ray near edge absorption structure (XANES) spectroscopy. The spectra confirmed the existence of disulfide bonds in oxidised (oxygen stream) glutenin subunits, supporting their significance for the formation of gluten networks. Additionally, glutenin subunits, which were stored under ambient air and temperature conditions, predominantly contained sulfur of higher oxidation states (sulfoxide, sulfonic acid). The disulfide state and also sulfoxide and sulfonic acid states were detected after reoxidation of glutenin subunits with potassium bromate. 相似文献
118.
Nina Franko Lucija Ana Vr
aj Taja Zore Barbara Ostanek Janja Marc Jasna Lojk 《International journal of molecular sciences》2022,23(8)
RT-qPCR is the gold standard and the most commonly used method for measuring gene expression. Selection of appropriate reference gene(s) for normalization is a crucial part of RT-qPCR experimental design, which allows accurate quantification and reliability of the results. Because there is no universal reference gene and even commonly used housekeeping genes’ expression can vary under certain conditions, careful selection of an appropriate internal control must be performed for each cell type or tissue and experimental design. The aim of this study was to identify the most stable reference genes during osteogenic differentiation of the human osteosarcoma cell lines MG-63, HOS, and SaOS-2 using the geNorm, NormFinder, and BestKeeper statistical algorithms. Our results show that TBP, PPIA, YWHAZ, and EF1A1 are the most stably expressed genes, while ACTB, and 18S rRNA expressions are most variable. These data provide a basis for future RT-qPCR normalizations when studying gene expression during osteogenic differentiation, for example, in studies of osteoporosis and other bone diseases. 相似文献
119.
Corn zein and wheat gliadin protein are compounded into synthetic cis-1,4-polyisoprene rubber (IR) and sulfur-cured in a zinc oxide (ZnO)-free system. The curing kinetics and mechanical and morphological properties are compared to a ZnO-activated or carbon black (CB)-reinforced cure system. The proteins provide reversion resistance and reinforcement to IR at filler loadings as low as 1 part per hundred rubber (phr). The zein-IR composites exhibit higher moduli, better filler–matrix adhesion, and less filler agglomeration/migration than gliadin-IR because zein is more chemically compatible with IR. The gliadin-IR composites have a lower percent set and hysteresis, indicating the formation of an elastic restoring gliadin network. Optimal properties are achieved at 2-phr gliadin and 4-phr zein. At gliadin loading >2 phr and zein loading >4 phr, the protein domain size increases and mechanical properties deteriorate. At equal filler loading, property improvements over CB-IR are observed for one or both proteins. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48141. 相似文献
120.
Gary J. Blomquist Charles L. Soliday Barbara A. Byers Joyce W. Brakke Larry L. Jackson 《Lipids》1972,7(5):356-362
Wax esters of secondary alcohols constitute 18–20% of the cuticular lipid extract ofMelanoplus packardii and 26–31% of the cuticular lipids ofMelanoplus sanguinipes. The total number of carbons in the wax esters range from 37–54 with 41 predominating in both species. The fatty acids ofM. packardii wax esters are 16∶0, 18∶0, 14∶0, 20∶0 and 12∶0 in decreasing quantity. The fatty acids ofM. sanguinipes wax esters are 18∶0, 20∶0, 16∶0 22∶0, 14∶0, 19∶0 and 17∶0 in decreasing quantity. The secondary alcohols from the wax esters
ofM. packardii are C25, C23 and C27 in decreasing quantity, and the secondary alcohols of theM. sanguinipes are C23, C25, C21, C27, C24, C22 and C26 in decreasing quantity. Each secondary alcohol consists of two to four isomers with the hydroxyl group located near the center
of the chain.
Montana Agriculture Experiment Station, Journal Series No. 332. 相似文献