2,740 research outputs found
Investigation of the retronasal perception of palm wine (Elaeis Guineensis) aroma by application of sensory analysis and exhaled odorant measurement (exom).
The headspace profile of palm wine was evaluated by time-resolved sensory analysis showing significant changes of the diverse odour attributes with time after
swallowing. Fruity and citrusy were the most intense aroma qualities perceived upon
sample introduction into the mouth, while swallowing of the palm wine elicited a
more acidic impression followed by citrusy and fruity nuances respectively. After
swallowing, panelists described an increase in the nutty and popcorn-like aroma
impressions.
Based on these sensory observations, the retronasal aroma perception of palm wine
was investigated by application of the modified Exhaled Odorant Measurement
(EXOM)-approach. In EXOM analysis, odorants that are exhaled through the nose
during food consumption and swallowing are collected and analysed by high
resolution gas chromatography-olfactometry and mass spectrometry, respectively.
EXOM results revealed an initial 24 odor-active compounds in the \'swallow\' breath
with 23 of these odorants being identified on the basis of their odor qualities and
intensities, as well as chromatographic and mass spectral data. Only 14 compounds
were detectable in the exhaled breath 20 s after swallowing the palm wine and 11 of
these were subsequently identified. Generally, the identified odorants belonged to
very diverse odorant substance classes such as heteroaromatic compounds, esters,
alcohols, carbonyl and thio compounds and many more. Among these, higher
persistence intervals in the exhalation breath were obtained for the buttery smelling
compounds butan-2,3-dione and 3-hydroxy-butan-2-one (acetoine), 3-isobutyl 2-
methoxypyrazine with bell pepper-like aroma impression, the malty smelling 2- and
3-methylbutanols, and the coconut-like smelling γ-dodecalactone. The popcorn-like
smelling 2-acetyl 1-pyrroline, the fresh flowery linalool and two unknown compounds
with citrusy and buttery aroma impressions were only detectable at 20 s after
swallowing. Dynamic changes were also observed in retronasal sensory evaluations
that were attributed to specific palm wine odorants. Accordingly, both sensory and
analytical data on retronasal aroma perception of palm wine monitored the dynamic
flavour changes during palm wine consumption. Keywords: Retronasal, EXOM, swallow breath, 2-acetyl 1-pyrroline African Journal of Food, Agriculture, Nutrition and Development Vol. 9 (2) 2009: pp. 793-81
Changes in structure and aroma release from starch-aroma systems upon α-amylase addition
The influence of starch hydrolysis by α-amylase addition on structural properties and aroma release from starch-aroma systems was studied. A food model system composed of aqueous tapioca starch dispersion (4g dry starch/100g dispersion) and one aroma compound (menthone) was investigated. Structure breakdown and related changes in starch fraction (amylose) were measured by rheology and iodine-binding. Menthone release from the aroma-starch system in the headspace was followed by proton transfer reaction-mass spectrometry (PTR-MS) upon starch hydrolysis. A slightly higher viscosity was found for the starch-menthone system compared to the starch system without menthone upon α-amylase addition. One could hypothesise that menthone acts as a kind of nucleation agent for inducing structure build-up of starch segments, hindering starch degradation. An extensive aroma release from aroma-starch systems upon α-amylase addition was expected, but, instead, just a slight volatile increase was found after a starch hydrolysis time of 60min. It is suggested that aroma release is the result of several superimposed effects ranging from viscosity effects to interactions between aroma compounds and starch degradation product
The Design and Implementation of a High-Speed Incremental Portable Prolog Compiler
The design and implementation of a relatively portable Prolog compiler achieving 12K LIPS on the standard benchmark is described. The compiler is incremental and uses decompilation to implement retract, clause, and listing, as well as support the needs of its four-port debugger. The system supports modules, garbage collection, database pointers, and a full range of built-ins
Integrating testing for chronic strongyloidiasis within the Indigenous adult preventive health assessment system in endemic communities in the Northern Territory, Australia: An intervention study
Background
The life-threatening clinical manifestations of strongyloidiasis are preventable with early detection and effective treatment. The aim of this study was to assess if there was an increase to the number and proportion of persons tested for chronic strongyloidiasis, as a result of integrating Strongyloides stercoralis serology into the existing preventive health assessment system in four Aboriginal health services in endemic communities.
Methodology
A prospective, longitudinal, before-and-after intervention study was conducted in four Aboriginal health services in remote endemically infected communities in the Northern Territory, Australia, from July 2012 to December 2016. The electronic patient information and recall systems enabled the integration of Strongyloides stercoralis serology into the adult preventive health assessment. Strongyloides reports for each health service were extracted half-yearly to examine the number and proportion of persons tested for chronic strongyloidiasis during the study and to measure the effect of the intervention.
Principal findings
The number and proportion of persons tested increased significantly during the study. From a total resident population of 3650 Indigenous adults over 15 years of age, 1686 persons (47.4%) were tested. The percentage of adults who had at least one serology test increased in all four health services to between 41% (446/1086) and 81.9% (172/210). Of the 1686 persons tested, 680 positive cases of chronic strongyloidiasis (40.3%) were identified.
Conclusions/Significance
This population health systems intervention increased the number and proportion of persons tested for chronic strongyloidiasis in four health services in endemically infected communities. This intervention is relevant to other health services with high-risk populations
Proteomic and immunoproteomic characterization of a DIVA subunit vaccine against Actinobacillus pleuropneumoniae
<p>Abstract</p> <p>Background</p> <p>Protection of pigs by vaccination against <it>Actinobacillus pleuropneumoniae</it>, the causative agent of porcine pleuropneumonia, is hampered by the presence of 15 different serotypes. A DIVA subunit vaccine comprised of detergent-released proteins from <it>A. pleuropneumoniae </it>serotypes 1, 2 and 5 has been developed and shown to protect pigs from clinical symptoms upon homologous and heterologous challenge. This vaccine has not been characterized in-depth so far. Thus we performed i) mass spectrometry in order to identify the exact protein content of the vaccine and ii) cross-serotype 2-D immunoblotting in order to discover cross-reactive antigens. By these approaches we expected to gain results enabling us to argue about the reasons for the efficacy of the analyzed vaccine.</p> <p>Results</p> <p>We identified 75 different proteins in the vaccine. Using the PSORTb algorithm these proteins were classified according to their cellular localization. Highly enriched proteins are outer membrane-associated lipoproteins like OmlA and TbpB, integral outer membrane proteins like FrpB, TbpA, OmpA1, OmpA2, HgbA and OmpP2, and secreted Apx toxins. The subunit vaccine also contained large amounts of the ApxIVA toxin so far thought to be expressed only during infection. Applying two-dimensional difference gel electrophoresis (2-D DIGE) we showed different isoforms and variations in expression levels of several proteins among the strains used for vaccine production. For detection of cross-reactive antigens we used detergent released proteins of serotype 7. Sera of pigs vaccinated with the detergent-released proteins of serotypes 1, 2, and 5 detected seven different proteins of serotype 7, and convalescent sera of pigs surviving experimental infection with serotype 7 reacted with 13 different proteins of the detergent-released proteins of <it>A. pleuropneumoniae </it>serotypes 1, 2, and 5.</p> <p>Conclusions</p> <p>A detergent extraction-based subunit vaccine of <it>A. pleuropneumoniae </it>was characterized by mass spectrometry. It contained a large variety of immunogenic and virulence associated proteins, among them the ApxIVA toxin. The identification of differences in expression as well as isoform variation between the serotypes implied the importance of combining proteins of different serotypes for vaccine generation. This finding was supported by immunoblotting showing the induction of cross-reactive antibodies against several surface associated proteins in immunized animals.</p
Mutations in the 3'-untranslated region of GATA4 as molecular hotspots for congenital heart disease (CHD)
<p>Abstract</p> <p>Background</p> <p>The 3'-untranslated region (3'-UTR) of mRNA contains regulatory elements that are essential for the appropriate expression of many genes. These regulatory elements are involved in the control of nuclear transport, polyadenylation status, subcellular targetting as well as rates of translation and degradation of mRNA. Indeed, 3'-UTR mutations have been associated with disease, but frequently this region is not analyzed. To gain insights into congenital heart disease (CHD), we have been analyzing cardiac-specific transcription factor genes, including <it>GATA4</it>, which encodes a zinc finger transcription factor. Germline mutations in the coding region of <it>GATA4 </it>have been associated with septation defects of the human heart, but mutations are rather rare. Previously, we identified 19 somatically-derived zinc finger mutations in diseased tissues of malformed hearts. We now continued our search in the 609 bp 3'-UTR region of <it>GATA4 </it>to explore further molecular avenues leading to CHD.</p> <p>Methods</p> <p>By direct sequencing, we analyzed the 3'-UTR of <it>GATA4 </it>in DNA isolated from 68 formalin-fixed explanted hearts with complex cardiac malformations encompassing ventricular, atrial, and atrioventricular septal defects. We also analyzed blood samples of 12 patients with CHD and 100 unrelated healthy individuals.</p> <p>Results</p> <p>We identified germline and somatic mutations in the 3'-UTR of <it>GATA4</it>. In the malformed hearts, we found nine frequently occurring sequence alterations and six dbSNPs in the 3'-UTR region of <it>GATA4</it>. Seven of these mutations are predicted to affect RNA folding. We also found further five nonsynonymous mutations in exons 6 and 7 of <it>GATA4</it>. Except for the dbSNPs, analysis of tissue distal to the septation defect failed to detect sequence variations in the same donor, thus suggesting somatic origin and mosaicism of mutations. In a family, we observed c.+119A > T in the 3'-UTR associated with ASD type II.</p> <p>Conclusion</p> <p>Our results suggest that somatic <it>GATA4 </it>mutations in the 3'-UTR may provide an additional molecular rationale for CHD.</p
Australian women's prediagnostic values and influencing sociodemographic variables relating to treatment choices for early breast cancer treatment
Women are often asked by their doctors to choose their preferred treatment for early breast cancer. Evidence shows that many women are distressed and confused about how to make this treatment decision and frequently seek help from nurses. Very little is known about women's value-centred decision-making in relation to selecting treatment for breast cancer and for nurses it is difficult to know how to assist these women with this process. In this study, 377 women participated prior to undergoing routine mammography screening and the data were collected using the Pre-Decision Portfolio Questionnaire (PDPQ) by Pierce 1. The partipants identified that expected treatment outcomes were the most important factor in choosing early breast cancer treatment. The majority reported that it was very important that a treatment would reduce the chances the cancer would return (95.6%), increase the length of their life (82.1%) and lead them to being healthy (80.4%). In addition, the participants indicated that it was important, or very important, that the emotional consequences of the treatment did "not make you depressed" (88.6%) or "sad" (90.4%) and should "keep you from worrying" (97%) and "give you peace of mind" (98.6%). Other factors, such as treatment's side effects, were identified as less important. Age, employment, education and having a family history of breast cancer were found to be significant influencing variables on the values of the participants. It was concluded that assessing and understanding the treatment values of women can help nurses focus on areas of importance to the woman and lead to informed decision-making when they are choosing treatment for early breast cancer
Minimization of free radical damage by metal catalysis of multivitamin/multimineral supplements
Multivitamin/multimineral complexes are the most common dietary supplements. Unlike minerals in foods that are incorporated in bioorganic structures, minerals in dietary supplements are typically in an inorganic form. These minerals can catalyze the generation of free radicals, thereby oxidizing antioxidants during digestion. Here we examine the ability of a matrix consisting of an amino acid and non-digestible oligosaccharide (AAOS) to blunt metal-catalyzed oxidations. Monitoring of ascorbate radical generated by copper shows that ascorbate is oxidized more slowly with the AAOS matrix than with copper sulfate. Measurement of the rate of oxidation of ascorbic acid and Trolox® by catalytic metals confirmed the ability of AAOS to slow these oxidations. Similar results were observed with iron-catalyzed formation of hydroxyl radicals. When compared to traditional forms of minerals used in supplements, we conclude that the oxidative loss of antioxidants in solution at physiological pH is much slower when AAOS is present
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