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Abstract Background Gastrointestinal stromal tumours (GISTs) represent a heterogeneous group of tumours of mesenchymal origin characterized by gain-of-function mutations in KIT or PDGFRA of the type III receptor tyrosine kinase family. Although mutations in either receptor are thought to drive an early oncogenic event through similar pathways, two previous studies reported the mutation-specific gene expression profiles. However, their further conclusions were rather discordant. To clarify the molecular characteristics of differentially expressed genes according to GIST receptor mutations, we combined microarray-based analysis with detailed functional annotations. Methods Total RNA was isolated from 29 frozen gastric GISTs and processed for hybridization on GENECHIP® HG-U133 Plus 2.0 microarrays (Affymetrix). KIT and PDGFRA were analyzed by sequencing, while related mRNA levels were analyzed by quantitative RT-PCR. Results Fifteen and eleven tumours possessed mutations in KIT and PDGFRA, respectively; no mutation was found in three tumours. Gene expression analysis identified no discriminative profiles associated with clinical or pathological parameters, even though expression of hundreds of genes differentiated tumour receptor mutation and expression status. Functional features of genes differentially expressed between the two groups of GISTs suggested alterations in angiogenesis and G-protein-related and calcium signalling. Conclusion Our study has identified novel molecular elements likely to be involved in receptor-dependent GIST development and allowed confirmation of previously published results. These elements may be potential therapeutic targets and novel markers of KIT mutation status.

Background: Gels of potato starches with varying amylose content were prepared and the degree of pasting and the course of retrogradation were studied. The average molar masses of granular and pasted starches were estimated. Determination of the degree of pasting involved use of optical microscopy and the study of pasting characteristics. The studies of susceptibility to retrogradation considered mechanical spectra, hardness, syneresis, resistant starch content, and X‐ray measurements. Results: Heating of the starch suspensions at 95 °C resulted in almost complete deterioration of granules. Changes in storage modulus (G') exceeded these of loss modulus (G"). Values of G' and G", hardness and syneresis increased with the period of the sample storage and, simultaneously, the relevant tangent of the phase shift angle (tg (G"/G')) decreased. A tendency was observed for the resistant starch (RS) content to increase on prolonged storage of gels. The patterns of diffractograms for the pasted and lyophilized samples only differed slightly. Conclusion: The pastes of all the studied potato starches were characterized by a similar degree of pasting. The most essential changes in the physicochemical properties of the gels were observed between the 30th and 90th days of storage. The susceptibility of potato starch gels to retrogradation, especially within the first 2 h, was controlled, mainly by the amylose content. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

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Recipes were designed for cookies with sucrose substituted with alternative sweeteners such as xylitol, sucralose and acesulfame K applied either separately or in blends. Rheological and textural properties of resulting doughs were examined. Sensory and textural parameters of cookies were compared with control samples sweetened with sucrose. Viscoelastic properties of the products containing blends of xylitol ( X) with acesulfame K ( A) ( X25A75) and X with sucralose ( S) ( X50S50) most closely resembled those found for control sample. Doughs sweetened with blends dominated by xylitol had properties best resembling those for control dough. Hardness of baked cookies best resembled that of control when they contained either acesulfame K as the sole additive or a blend of xylitol with sucralose ( X50S50). According to the sensory analyses, cookies sweetened with sucrose received the highest score (4.38 points), whereas those sweetened with a blend of xylitol and acesulfame K ( X75A25, X50A50) received 3.47 and 3.30 points, respectively. Practical Applications The study offers the sugar-free cookies sweetened either with xylitol or with a blend of xylitol and acesulfame K ( X75A25, X50A50), which enjoyed with an appreciation of the sensory panel. The sugar-free cookies elaborated in the presented study could be useful for people suffering from type 2 diabetes as well as for people with obesity. These are mostly diseases of civilization and people suffering from them have limited possibilities of sweet snack consumption. An application of technology, which uses alternative sweeteners, could be an excellent addition to their diet in sweet snacks. [ABSTRACT FROM AUTHOR]

Photodeposition of gold on TiO2 was conducted in situ in the photoreactor used for the reaction of phenol photodestruction. The Au/TiO2 system shows better photocatalytic properties in the destruction of phenol contaminants in water than pure TiO2. The gold cocatalyst prevents also the decrease of the rate of the photocatalytic reaction at higher phenol concentration observed for pure TiO2. Hydroquinone, p-benzoquinone, and catechol are main intermediates of the photoreaction, which finally leads to total phenol mineralization. [ABSTRACT FROM AUTHOR]

Background: Gastrointestinal stromal tumours (GISTs) represent a heterogeneous group of tumours of mesenchymal origin characterized by gain-of-function mutations in KIT or PDGFRA of the type III receptor tyrosine kinase family. Although mutations in either receptor are thought to drive an early oncogenic event through similar pathways, two previous studies reported the mutation-specific gene expression profiles. However, their further conclusions were rather discordant. To clarify the molecular characteristics of differentially expressed genes according to GIST receptor mutations, we combined microarray-based analysis with detailed functional annotations., Methods: Total RNA was isolated from 29 frozen gastric GISTs and processed for hybridization on GENECHIP HG-U133 Plus 2.0 microarrays (Affymetrix). KIT and PDGFRA were analyzed by sequencing, while related mRNA levels were analyzed by quantitative RT-PCR., Results: Fifteen and eleven tumours possessed mutations in KIT and PDGFRA, respectively; no mutation was found in three tumours. Gene expression analysis identified no discriminative profiles associated with clinical or pathological parameters, even though expression of hundreds of genes differentiated tumour receptor mutation and expression status. Functional features of genes differentially expressed between the two groups of GISTs suggested alterations in angiogenesis and G-protein-related and calcium signalling., Conclusion: Our study has identified novel molecular elements likely to be involved in receptor-dependent GIST development and allowed confirmation of previously published results. These elements may be potential therapeutic targets and novel markers of KIT mutation status.

Background: The development of accurate diagnostic methods in gastrointestinal stromal tumors (GISTs) and the introduction of imatinib (IM) therapy has focused attention on the factors influencing the prognosis of patients with primary lesions as well as of patients with advanced disease treated with imatinib., Material/methods: The clinico-pathological and genetic factors influencing disease-free survival (DFS) in 335 patients with primary CD117-immunopositive tumors (group A; calculated from primary tumor resection) and progression-free survival (PFS) in 232 metastatic/unresectable GIST patients treated with IM (group B; calculated from the start of imatinib therapy) were analyzed., Results: In group A, statistically significant factors negatively influencing DFS(five-year DFS: 38%), both in univariate and multivariate analysis, were: primary tumor size >5 cm, mitotic index >5/50 HPF (high-power fields), male gender, primary tumor R1 resection or tumor rupture, non-gastric primary tumor localization. In group B, five factors negatively affecting PFS (three-year PFS: 54%) were identified, which were statistically significant both in univariate and multivariate analyses: WHO performance status >/=2, tumor genotype indicating other than exon 11 KIT mutation, high baseline pre-IM granulocyte count, mitotic index >10/50 HPF, and age <45 years at diagnosis., Conclusions: Different sets of independent biological and pathological prognostic factors were identified for the assessment of the natural course of primary GIST and for the prediction of PFS during IM therapy for advanced GIST.