681 research outputs found
Proteomics analysis for amino acid misincorporation detection: mini review
Protein biosynthesis is a highly accurate biological process essential for life. Amino acid misincorporation errors
(mistranslation) normally occur at low levels, but can increase sharply upon amino acid starvation, exposure to
drugs, oxidative stress and other physiological perturbations. These processes disrupt protein function and are
normally regarded as being deleterious, however, recent work has shown that they can also be regulated to
produce advantageous phenotypes in both prokaryotes and eukaryotes. The biology of such unexpected adaptive
mistranslation is poorly understood due to technical difficulties in the identification and quantification of amino
acid misincorporations. In this mini-review, we describe proteome scale methodologies involving the use of massspectrometry and bioinformatics tools to directly detect and quantify mistranslation events and also indirect functional
methods that permit sensitive, flexible and low-cost analysis of site specific amino acid variation.publishe
Identification of duck, partridge, pheasant, quail, chicken and turkey meats by species-specific PCR assays to assess the authenticity of traditional game meat Alheira sausages
Game meat Alheira (Alheira de caça) sausage is a traditional fermented product typical from the Northeast region of Portugal, having bread and meats (including game) as main ingredients. It is a particularly appreciated product by consumers that commands higher prices, especially in comparison with the common Alheira produced with pork and poultry meats. Following our previous work in which several mammalian game meat species were successfully identified in game meat Alheira sausages for authentication purposes, the present work aimed at identifying game bird's species for the overall assessment of labelling compliance. For that purpose, several species-specific PCR assays targeting mitochondrial DNA for the detection of game and domestic bird's meat, namely duck, partridge, pheasant, quail, chicken and turkey were developed, optimised and applied to commercial samples of game meat Alheira for their authentication. The assays revealed a high specificity and sensitivity to detect the addition of all evaluated species down to a level of 0.01% (w/w). PCR results indicated the existence of several inconsistencies with the labelled information, namely the absence of declared game species (duck, partridge and pheasant) and the presence of undeclared poultry meat, pointing out to adulterations owing to substitution of game by domestic meat species. Since this is considered a high-valued traditional product that should be valorised and protected, this work puts in evidence the need for inspection programs to enforce regulation. © 2014 Elsevier Ltd.The authors acknowledge the financial support of the University
of Porto/Santander Totta “Projectos pluridisciplinares 2010” and the
Fundação para a Ciência e a Tecnologia (FCT) through grant no.
PEst-C/EQB/LA0006/2013.info:eu-repo/semantics/publishedVersio
Monitorização da adulteração de suplementos alimentares à base de plantas comercializados em Portugal com inibidores de fosfodiesterase tipo 5 (PDE-5)
Na ultima década, assistiu-se a um consumo crescente de suplementos alimentares pela população
mundial, especialmente, no que diz respeito ao consumo de suplementos alimentares a base de
plantas 1. Estes são utilizados com diversas finalidades, tais como equilibrar a dieta, compensar uma
falta nutricional, manter a saúde, prevenir doenças crónicas, melhorar a aparência e o bem-estar
incluindo a condição mental, sexual e desportiva, entre outras 1. São produtos frequentemente
rotulados como "naturais" o que transmite uma falsa sensação de segurança aos consumidores.
Contudo, recentemente foi referida a ocorrência de adulterações nestes produtos, o que compromete
a sua segurança. Entre os casos de fraude detetados destaca-se a adição de substâncias ilegais.
Atualmente, os suplementos para melhorar o desempenho sexual estão entre os suplementos
alimentares mais populares entre os consumidores. A disfunção eréctil e uma doença que afeta 150
milhões de homens mundialmente sendo o tratamento recomendado a administração de fármacos
inibidores da enzima fosfodiesterase tipo 5 (PDE-5) 2. Os inibidores PDE-5 legalmente
comercializados a nível europeu são: citrato de sildenafil, tadalafil, hidrocloreto de vardenafil e
avanafil 3. Estas são substâncias com efeitos secundários graves quando administrado
concomitantemente com medicamentos como nitratos ou a-bloqueadores 4.
0 objetivo deste trabalho foi, por isso, a monitorização da presença de adulterantes do tipo inibidores
PDE-5 em suplementos alimentares a base de plantas vendidos com o objetivo de melhorar a
performance sexual. Foram analisados doze suplementos alimentares, adquiridos no mercado
português. Estes suplementos foram pesquisados quanto a presença de sildenafil, acetildenafil,
tiosildenafil, tadalafil, vardenafil e yombina, atraves de metodo de crornatografia líquida de elevada
performance acoplada a detetor de díodos e detetor de fluorescência em série (HPLC-DAD-FL). Dos
doze suplementos analisados, seis revelaram a presença de um ou mais dos inibidores PDE-5
referidos. Adicionalmente, dois outros suplementos revelaram a presença de dois compostos, cujo
espectro UV-Vis leva a suspeição de uma possível adulteração com compostos análogos às substâncias pesquisadas.info:eu-repo/semantics/publishedVersio
On the Fe abundance peak formation in cool-core clusters of galaxies: hints from cluster WARPJ1415.1+3612 at z=1.03
We present a detailed study of the iron content of the core of the
high-redshift cluster WARPJ1415.1+3612 (z=1.03). By comparing the central Fe
mass excess observed in this system, M_Fe^exc = (1.67 +/- 0.40) x 10^9 M_sun,
with those measured in local cool-core systems, we infer that the bulk of the
mass excess was already in place at z=1, when the age of the Universe was about
half of what it is today. Our measures point to an early and intense period of
star formation most likely associated with the formation of the BCG. Indeed, in
the case of the power-law delay time distribution with slope -1, which
reproduces the data of WARPJ1415.1+3612 best, half of the supernovae explode
within 0.4 Gyr of the formation of the BCG. Finally, while for local cool-core
clusters the Fe distribution is broader than the near infrared light
distribution of the BCG, in WARPJ1415.1+3612 the two distributions are
consistent, indicating that the process responsible for broadening the Fe
distribution in local systems has not yet started in this distant cluster.Comment: 10 pages, accepted for publication in A&A, minor language corrections
added in v
Detection of adulterations in tradictional portuguese game meat products by polymerase chain reaction technique
Authenticity assessment and fraud detection in processed meat products have becn attracting an
increased attention driven by public health, economic and legal cancems, and also for religiolls
reasons. Currcntly, ooe af the major issues conceming adulterations in the meat indust:ry regards the
fraudulent substitution af higher commercial valued meat species by less expensive oDes [1]. The
manufacture af traditional meat products is a long-established practice in the Northeast of Portugal.
One of the most appreciated products is called "Alheiras", which are traditional smoked fermented
sausages, mainly produced with pork and poultry meat. In addition to the two Portuguese Alheiras with
Protected Geographical Indication (pGI), other types of "Alheiras" are now available in the market,
including the ones produced with game meat. Due to the game meat particular taste, intense Oavour
and seasonality, it generally eommands higher prices compared to other meats [1]. Sinee game meat
"Alheiras" should, totally or partially, include different types of game meat, they are particularly prone
to fraudulent meat substitutions
Sponge perforating lace coral with anticancer activity
This short note reports results from a pilot study to investigate new anticancer agents from deepsea corals in which colonizing sponges were encountered. The pure white stylasterid coral fans of Errina dabneyi (Pourtalès, 1871) are a conspicuous feature on the upper bathyal slopes in Azorean waters and can be found in depths from 215 to more than 500 m (Wisshak et al. 2009; Braga-Henriques et al. 2013). From the 26 species of Errina known worldwide (most from deeper waters) (Cairns 1983), E. dabneyi seems to be endemic to the Azores Archipelago and the adjacent Mid-Atlantic Ridge region (Zibrowius & Cairns 1992; Braga-Henriques et al. 2013).
[…]
Species identification and authentication of hare (Lepus) meat by the use of the mitochondrial cytb gene
Nowadays, consumers are increasingly concerned with issues of food safety and authenticity. In
particular, game meat has been much appreciated by consumers for their exotic flavour and
texture, low in fat and cholesterol as well as by the absence of steroids or other drugs. Food
authenticity assessment is important in that it avoids unfair competition among producers and
allows consumers to have accurate information about the products they purchase. Therefore, it is
important to ensure that species of high commercial value declared are not replaced by other species of lesser value [I]
Deep X-ray and IR study of the distant X-ray cluster XDCP J0044.0-2033 «Gioiello» at z=1.6
A recent, deep exposure using NASA’s Chandra X-ray Observatory showed strong diffuse X-ray emission from the high redshift cluster XDCP0044, discovered in 2011 in the framework of the XMM Distant Cluster Project. This is the deepest X-ray observation yet made on a cluster beyond a distance of about 8 billion light years. At the same time, Infrared observations from ESA’s Herschel Space Observatory showed intense star formation in the center of XDCP0044, providing for the first time a snapshot of the epoch when the stars of the most massive cluster members are still forming. The two works originating from these data are led by the authors of this short contribution.A recent, deep exposure using NASA’s Chandra X-ray Observatory showed strong diffuse X-ray emission from the high redshift cluster XDCP0044, discovered in 2011 in the framework of the XMM Distant Cluster Project. This is the deepest X-ray observation yet made on a cluster beyond a distance of about 8 billion light years. At the same time, Infrared observations from ESA’s Herschel Space Observatory showed intense star formation in the center of XDCP0044, providing for the first time a snapshot of the epoch when the stars of the most massive cluster members are still forming. The two works originating from these data are led by the authors of this short contribution
Authentication of a traditional game meat sausage (Alheira) by species-specific PCR assays to detect hare, rabbit, red deer, pork and cow meats
Alheira is a traditional meat product that is typical from the Northeast region of Portugal and much appreciated. It is a sort of sausage produced industrially or by small artisanal producers, having wheat bread and meats as main ingredients. Game meat Alheira (Alheira de caça) is considered one of the most attractive products since it should include different game meats. The aim of the present work was to identify the species of origin of meats added to game meat Alheira samples to verify their compliance with labelling. Species-specific PCR assays targeting mitochondrial genes of rabbit, hare, red deer, cow and pork were optimised and applied to industrial and artisanal samples. The assays revealed adequate specificity for each of the targeted species, with sensitivities of 0.01-0.1%. Results of the evaluation of 18 commercial samples identified several inconsistencies with labelling, namely the absence of declared game species (red deer, hare and rabbit) in ten samples and the presence of undeclared cow species in nine of the analysed samples. These findings indicate the occurrence of misleading labelling, suggesting the adulteration by substitution of game meats by cow meat to reduce production costs and the need to protect and valorise this kind of traditional food product.The authors acknowledge the financial support of the University
of Porto/Santander Totta “Projectos pluridisciplinares 2010” and
the Fundação para a Ciência e a Tecnologia (FCT) through grant no.
PEst-C/EQB/LA0006/2013.info:eu-repo/semantics/publishedVersio
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