Prenatal diagnosis. II. Importance of ultrasonographic markers in prenatal diagnosis of chromosome abnormalities]

The Medical Genetic Unit of the University of Zulia (MGUUZ) has developed a Prenatal Diagnosis Program (PDP) since January-1993, in which Genetic Risk Factors are determined in couples who request prenatal genetic counseling. In this program, different prenatal diagnostic procedures are performed to detect congenital defects during intrauterine life. One of these procedures is the Fetal Sonogram (FS). FS is a non invasive technique which permits the prenatal diagnosis of many genetic dysmorphic syndromes. Through the search of abnormal specific characteristics in the fetus, chromosomopathies may be suspected. These findings are named "Echosonographic Markers of Chromosomal Abnormalities" (EMCA). During three years (January-1993 to December-1996), patients attended in the PDP included 321 pregnant women in which 312 FS were performed. Abnormal outcomes were 22 (17 with isolated congenital malformations and 5 with EMCA). Only one fetus with chromosome abnormality (46,XX21q-) could not be detected by FS. The goals of this paper are: 1) to report 5 patients with sonographic markers suggestive of chromosomal abnormalities and 2) to show the FS usefulness in prenatal diagnosis of chromosompathies. We conclude that, in the search of the EMCA the FS should be offered systematically to all pregnant women without recognizable genetic risk. They are the main group with optimal reproductive age and in consequence, with the possibility of having a relatively major number of conception outcomes with congenital defects, with or without chromosomic etiology. The majority of those defects can be detected by FS and could allow us to select the patients in which the use of an invasive prenatal diagnostic procedure could be justified.     

Live weight and sex effects on carcass and meat quality of "Borrego terrincho-PDO" suckling lambs

Fifty seven suckling lambs (28 males and 29 females) of the Churra da Terra Quente breed were used to evaluate the effects of live weight and sex on carcass composition and meat quality traits. Lambs were slaughtered at three weight classes (<8 kg, 8–11 kg and >11 kg) according to “Borrego Terrincho–PDO” specifications. The left sides of the carcasses were totally dissected. The longissimus thoracis and lumborum muscle was used for meat quality determination. Dressing proportion and carcass fatness were not affected by weight class or sex. Muscle proportion was similar in all carcass joints for the three weight classes. The percentage of bone decreased at the higher weight class, while that of subcutaneous and intermuscular fat increased. Female lambs had higher muscle proportions and greater muscle/bone ratios in the carcass side than males. Muscle pH, colour, cooking losses and tenderness were not affected by gender and weight class. Female lambs and weight classes 8–11 kg and >11 kg had higher proportions of intramuscular fat.     

Superstructures of Self‐Organizing Thiophenes

The self‐assembling properties of π‐conjugated oligo‐, poly‐, and cyclothiophenes (see Figure) have been studied with different techniques. Scanning tunneling microscopy on perfectly ordered two‐dimensional monolayers at the solution–HOPG (highly oriented pyrolytic graphite) interface has successfully been applied. The submolecular resolution achieved in the STM images provides valuable lattice and molecular information. Supported by X‐ray structure analyses of the 3D bulk material and by theoretical calculations, molecular conformations, molecule–molecule, and molecule–substrate interactions of the oligo‐, poly‐, and cyclomers have been analyzed and discussed.     

Melamine Detection in Milk and Dairy Products: Traditional Analytical Methods and Recent Developments

Melamine is a nitrogen-rich compound (about 66%) whose fraudulent addition to foods aims to increase the apparent protein content. In 2008, melamine adulteration incidents occurred in China caused several deaths in humans from kidney failure and other health problems. This issue prompted private as well as governmental laboratories to develop several analytical methods in order to determine melamine in foods. This review aims to provide an overview of the analytical techniques currently available in the literature for melamine detection and measurement in milk and dairy products, including a specific section related to sample preparation. Recent studies concerning conventional (both screening and confirmatory) methods are reported, and technical and critical issues are discussed for each technique (liquid and gas chromatography, mass spectrometry, liquid chromatography coupled to mass spectrometry, gas chromatography coupled to mass spectrometry, and capillary electrophoresis). These techniques, very sensitive and specific but also time-consuming, may require tedious sample preparation, costly instrumentation, and skilled personnel. Therefore, new innovative detection methods are also provided, focusing attention on immunoassay, sensor technology, vibrational spectroscopy coupled to chemometrics, hyperspectral imaging, micellar liquid chromatography, magnetic resonance spectroscopy, and chemiluminescence.     

Decay of dinitroaniline herbicides and organophosphorus insecticides during brewing of lager beer

This article examines the fate of four pesticides that can be present during the brewing of lager beer. For this purpose, malted barley was spiked at 2 mg/kg with pendimethalin and trifluralin (dinitroaniline herbicides) and fenitrothion and malathion (organophosphorus insecticides). Analyses of pesticide residues were carried out by a gas chromatograph with an electron capture detector, and their identity was confirmed by gas chromatography-mass spectrometry. Cleanup was necessary for the malt and spent grain samples. Beginning with mashing and ending with the final product 4 months later, various samples (spent grain, sweet wort, brewer wort, and beer) were taken to determine the concentration of the targeted residual pesticides during the various beer making phases. In all cases, the residual levels recorded in sweet wort sampled after the mashing phase were below the respective maximum residue limits established by Spanish legislation for barley. Significant proportions of pesticide residues (17 to 40%) were retained on the spent grain. Applying the standard first-order kinetics equation (r > 0.91), the half-lives obtained for the four compounds during the storage of the spent grain (3.5 months) varied from 138 days (fenitrothion) to 192 days (malathion and pendimethalin). Herbicide residues practically disappeared (<0.3%) after wort boiling, whereas the percentages of the remaining insecticides, fenitrothion and malathion, ranged from 3.5 to 4.3%, respectively, at this time. No residues of dinitroaniline compounds were detected in young beer, whereas there was a significant reduction in fenitrothion (58%) and malathion (71%) residues during fermentation. Lagering and filtering processes also reduced the content of the organophosphorus insecticides (33 to 37%). Finally, after the storage period (3 months), the content of fenitrothion was reduced by 75%, with malathion residues being below its detection limit.     

Dynamic evaluation of two configurations for a hybrid DFIG‐based wind turbine integrating battery energy storage system

Hybrid systems comprising battery energy storage systems (BESSs) and wind power generation entail considerable advances on the grid integration of renewable energy. Doubly fed induction generators (DFIGs) stand out among different wind turbine (WT) technologies. On the other hand, electrochemical batteries have proved to be valid for these purposes. In this paper, a comparative analysis is carried out between two alternative configurations for hybrid WT‐BESS systems, where the BESS is connected either outside or inside the DFIG. The modeling of these two configurations and the control systems applied for achieving the coordinate operation of the energy sources (DFIG and batteries) are illustrated. The hybrid systems under study are evaluated by simulation under normal operation (wind speed fluctuations and grid demand changes) and grid faults. Simulation results show that both configurations improve the grid integration capability of the WT, although the configuration with external BESS presents better results since it can provide additional active/reactive power injection. Copyright © 2014 John Wiley & Sons, Ltd.     

Changes on indigenous microbiota,colour, bioactive compounds and antioxidant activity of pasteurised pomegranate juice

Juices prepared from arils of ‘Mollar’ pomegranates were analysed for naturally occurring microorganisms, CIE Lab colour parameters, total phenols, anthocyanins and punicalagins, ellagic acid content and antioxidant capacity before and after low-, mild- and high-temperature pasteurisations (LTPs, MTPs and HTPs): 65, 80 and 90 °C for 30 or 60 s. Mean aerobic plate count (APC), yeast and mold count (YMC), and lactic acid bacteria (LAB) for fresh juices were 5.7, 5.36 and 4.0 log CFU/mL, respectively. MTPs and HTPs were sufficiently effective to decrease APCs to nil or negligible levels. An increase in CIE a values and decrease in CIE b values were the characteristic colour changes in heat-treated juices. The effect of pasteurisations showed that total phenols, punicalagins and ellagic acid were not much affected by thermal processing. Total anthocyanin content and antioxidant capacity were substantially and significantly influenced by the heat treatment applied. A linear relationship was observed between Trolox equivalent antioxidant capacity (TEAC) values and total anthocyanins, suggesting that they contributed strongly to the antioxidant capacity of pomegranate juice.