CircRNAs as Potential Blood Biomarkers and Key Elements in Regulatory Networks in Gastric Cancer

Gastric cancer (GC) is the fifth most common type of cancer and the third leading cause of cancer death in the world. It is a disease that encompasses a variety of molecular alterations, including in non-coding RNAs such as circular RNAs (circRNAs). In the present study, we investigated hsa_circ_0000211, hsa_circ_0000284, hsa_circ_0000524, hsa_circ_0001136 and hsa_circ_0004771 expression profiles using RT-qPCR in 71 gastric tissue samples from GC patients (tumor and tumor-adjacent samples) and volunteers without cancer. In order to investigate the suitability of circRNAs as minimally invasive biomarkers, we also evaluated their expression profile through RT-qPCR in peripheral blood samples from patients with and without GC (n = 41). We also investigated the predicted interactions between circRNA-miRNA-mRNA and circRNA-RBP using the KEGG and Reactome databases. Overall, our results showed that hsa_circ_0000211, hsa_circ_0000284 and hsa_circ_0004771 presented equivalent expression profiles when analyzed by different methods (RNA-Seq and RT-qPCR) and different types of samples (tissue and blood). Further, functional enrichment results identified important signaling pathways related to GC. Thus, our data support the consideration of circRNAs as new, minimally invasive biomarkers capable of aiding in the diagnosis of GC and with great potential to be applied in clinical practice.     

Capillary electrophoresis characterization of the casein fraction of cheeses made from cows', ewes' and goats' milks

Casein fractions and their breakdown products in Iberico-type cheeses made from the milk of cows, ewes or goats were analysed by capillary electrophoresis in order to characterize them. The actions of plasmin and chymosin on caseins were evaluated by comparing the electropherograms of caseins from milk and from cheese, both with and without treatment with plasmin. Characteristic capillary electrophoresis patterns were obtained for cheeses made from the milk of each of the three species, and the main components were identified. Caprine para-kappa-casein and bovine beta-caseins, eluting at the first and at the last part of the electropherogram respectively, were found to be indicative of the presence of the milks of these species.     

A simple DNA extraction method suitable for PCR detection of genetically modified maize

BACKGROUND: The polymerase chain reaction (PCR) is a powerful tool that is being increasingly used for detection of transgenic DNA. PCR requires only a minute quantity of template, but sensitive and accurate testing requires DNA of sufficient purity and free from inhibitors such as plant polysaccharides. Several standard protocols are available for this purpose, but they usually involve several steps, imply destruction of the maize kernel, or are time‐consuming. Our aim was to develop a fast and simple extraction method to isolate a raw DNA‐containing solution from maize tissues suitable for use as a template in a PCR‐based detection assay with specific oligonucleotides directed to the identification of event MON810. RESULTS: The NaOH‐based DNA extraction method we report here is time‐saving (5 min) and can be used to isolate DNA‐containing solutions from a small maize leaf portion (down to 1 mg) or from a single overnight‐germinated kernel. PCR performed with selected primers yielded reproducible detection of transgenic DNA. CONCLUSION: The main advantages of the procedure are the quick extraction step, the possibility of non‐destructive testing of maize kernels, and the robustness of the PCR‐based detection, a consequence of the selection of MON810‐matching oligonucleotides yielding intense and highly specific amplicons. Copyright © 2007 Society of Chemical Industry     

Inactivation of Oxidative Enzymes by High-Intensity Pulsed Electric Field for Retention of Color in Carrot Juice

The effects of high-intensity pulsed electric fields (HIPEF) on oxidative enzymes and color of fresh carrot juice were studied. A response surface methodology (RSM) was used to evaluate the effect of pulse polarity (mono or bipolar mode), pulse width (from 1 to 7 μs), and pulse frequency (from 50 to 250 Hz) on color and peroxidase (POD) inactivation of carrot juice treated by HIPEF. The total treatment time and the electric field strength were set at 1,000 μs and 35 kV/cm, respectively, at a temperature below 35°C. The physicochemical characteristics of carrot juice were measured. There was a linear relationship between electrical conductivity and temperature of the carrot juice. The results showed that HIPEF-treated carrot juice at 35 kV/cm for 1,000 μs applying 6 μs pulse width at 200 Hz in bipolar mode led to 73.0% inactivation of POD. The color coordinates did not change significantly. Therefore, HIPEF was effective in POD inactivation and carrot juice color preservation.     

Determination of the casein content in bovine milk by 31P-NMR

The relative proportion of caseins to total protein is a parameter that can be used to control the protein quality in standardised milk, an increasing tendency in dairy industries. 31P-NMR was used to analyse the casein content of milk, by the quantitation of the area under the resonances belonging to SerP, and using methylenediphosphonic acid as internal standard. This procedure yielded good results, as similar values of caseins were obtained from N Kjeldahl and NMR analysis for slightly heated milk samples. Heating at 95 degrees C for 15 min did not alter the casein content results. Casein content of raw, pasteurised and UHT milks (25.6 +/- 1.4, 26.4 +/- 1.8, 25.5 +/- 1.6 g casein/l milk, respectively), obtained by NMR, were not significantly different, giving an average of 25.8 +/- 1.6 g casein/l for bulk liquid milk. This work concluded that 31P-NMR could be used as an alternative method to determine casein in raw, pasteurised, dry and UHT milks.     

Cancer chemoprevention and chemotherapy: dietary polyphenols and signalling pathways

Prevention of cancer through dietary intervention recently has received an increasing interest, and dietary polyphenols have become not only important potential chemopreventive, but also therapeutic, natural agents. Polyphenols have been reported to interfere at the initiation, promotion and progression of cancer. They might lead to the modulation of proteins in diverse pathways and require the integration of different signals for the final chemopreventive or therapeutic effect. Polyphenols have been demonstrated to act on multiple key elements in signal transduction pathways related to cellular proliferation, differentiation, apoptosis, inflammation, angiogenesis and metastasis; however, these molecular mechanisms of action are not completely characterized and many features remain to be elucidated. The aim of this review is to provide insights into the molecular basis of potential chemopreventive and therapeutic activities of dietary polyphenols with emphasis in their ability to control intracellular signalling cascades considered as relevant targets in a cancer preventive approach.     

Stability of DON and DON-3-glucoside during baking as affected by the presence of food additives

The mycotoxin deoxynivalenol (DON) is one of the most common mycotoxins of cereals worldwide, and its occurrence has been widely reported in raw wheat. The free mycotoxin form is not the only route of exposure; modified forms can also be present in cereal products. Deoxynivalenol-3-glucoside (DON-3-glucoside) is a common DON plant conjugate. The mycotoxin concentration could be affected by food processing; here, we studied the stability of DON and DON-3-glucoside during baking of small doughs made from white wheat flour and other ingredients. A range of common food additives and ingredients were added to assess possible interference: ascorbic acid (E300), citric acid (E330), sorbic acid (E200), calcium propionate (E282), lecithin (E322), diacetyltartaric acid esters of fatty acid mono- and diglycerides (E472a), calcium phosphate (E341), disodium diphosphate (E450i), xanthan gum (E415), polydextrose (E1200), sorbitol (E420i), sodium bicarbonate (E500i), wheat gluten and malt flour. The DON content was reduced by 40%, and the DON-3-glucoside concentration increased by >100%, after baking for 20 min at 180°C. This confirmed that DON and DON-3-glucoside concentrations can vary during heating, and DON-3-glucoside could even increase after baking. However, DON and DON-3-glucoside are not affected significantly by the presence of the food additives tested.     

Ochratoxin A in wines,musts and grape juices from Spain

A survey on the occurrence of ochratoxin A (OTA) in 240 grape‐based beverages was carried out. Red and white wines from four different Spanish Designations of Origin (n = 160), musts (n = 20), grape juices (n = 10), ordinary wines (n = 20), special wines (Malaga, muscatel, sherry, vermouth, etc) (n = 20) and sparkling wines (n = 10) were assayed for OTA content using immunoaffinity column clean‐up and high‐performance liquid chromatography with fluorimetric detection (detection limit 0.05 µg l^?1). Forty‐three (17.9%) of the samples tested contained detectable levels of OTA. The overall mean OTA concentration in red and white wines of Designations of Origin was 0.30 and 0.18 µg l^?1 respectively (ranges 0.05–3.19 and 0.05–1.13 µg l^?1 respectively). The percentage of wine samples with detectable amounts of OTA was higher for red (18.3%) than for white (10%) wines. OTA was also found in two of 10 red ordinary wines (0.68 and 4.24 µg l^?1), whereas none of 10 white ordinary wines contained OTA. The mean OTA amount detected in sparkling wines was 0.44 µg l^?1 (range 0.14–0.71 µg l^?1). Two of 20 must samples contained OTA at low levels (0.08 and 0.18 µg l^?1), while none of 10 grape juice samples contained OTA. Highest amounts of OTA were found in special wines (45%), with a maximum of 15.25 µg l^?1 in a muscatel sample. Copyright © 2004 Society of Chemical Industry     

Angiotensin I-converting enzyme inhibitory activity of peptides derived from egg white proteins by enzymatic hydrolysis

The hydrolysis of crude egg white with pepsin, trypsin, and chymotrypsin produced peptides with angiotensin-converting enzyme (ACE) inhibitory properties. These peptides were mainly derived from the proteolysis of ovalbumin. The most active hydrolysates were obtained after treatment with pepsin (50% inhibitory concentration [IC50], 55.3 microg/ml), with the fraction having a molecular mass lower than 3,000 Da giving the highest ACE inhibitory activity (IC50, 34.5 microg/ml). Nine subfractions were collected from the fraction with a molecular mass lower than 3,000 Da using semipreparative reversed-phase high-performance liquid chromatography. Considerable ACE inhibitory activity (IC50 < 40 microg/ml) was found in three of them. These subfractions were analyzed by reversed-phase high-performance liquid chromatography-tandem mass spectrometry, and 14 peptides were identified. These sequences were synthesized, and their ACE inhibitory activities were measured. Among the identified peptides, two novel sequences with potent ACE inhibitory activity were found. The amino acid sequences of these inhibitors were identified as Arg-Ala-Asp-His-Pro-Phe-Leu and Tyr-Ala-Glu-Glu-Arg-Tyr-Pro-Ile-Leu and showed IC50 values of 6.2 and 4.7 microM, respectively.     

Phenotypic correlations among quality traits of fresh and dry-cured hams

In this study, fresh and processing quality traits were collected on a total of 312 Country Hams. Phenotypic correlations between traits were estimated and numerous values were significantly different (P<0.05) from zero. Yield was significantly correlated with several fresh pork quality traits measured on the fresh hams, including subjective color (0.34) and lipid percentage (0.32). Some meat color traits were significantly correlated, including associations between the color scores taken on the fresh and cured hams. Correlations between fresh pork quality traits were also determined, with results showing significant correlations between ultimate pH and other pork quality traits. The results indicate that yield can be maximized if hams with good fresh pork quality parameters are used for curing. The correlations estimates are helpful for understanding of the biological mechanisms behind the production of dry-cured hams and can potentially be used to improve the efficiency of the dry-cured ham production chain.