Previous studies from China, Spain, and the United States on genetically modified (GM) rice, cotton, and maize have concluded that the biodiversity of insects and related arthropods in GM crop fields was essentially the same as that among conventional crops. Now a new study from South Africa shows similar results.The study is described in an article called “Comparative Diversity of Arthropods on Bt Maize and Non-Bt Maize in two Different Cropping Systems in South Africa,” which appears in the February 2014 issue of Environmental Entomology.”The aims of the study were to compile a checklist of arthropods that occur on maize in South Africa and to compare the diversity and abundance of arthropods and functional groups on Bt maize and non-Bt maize,” the authors wrote. “Results from this short-term study indicated that abundance and diversity of arthropods in maize and the different functional guilds were not significantly affected by Bt maize, either in terms of diversity or abundance.”A total of 8,771 arthropod individuals, comprising 288 morphospecies, were collected from 480 plants sampled from Bt maize and non-Bt maize fields over a two-year period. The researchers found no significant differences in abundance or diversity in detritivores, herbivores, predators, or parasitoids.”The results of our study indicate that arthropod diversity, even in high-input farming systems, is as high as in subsistence farming systems” said Dr. Johnnie van den Berg, a professor at North-West University and one of the co-authors of the article. “More recently, surveys of arthropod and plant beta-diversity inside and adjacent to maize fields have been completed during which 30,000 arthropods and 15,000 plant individuals were surveyed along a 1,000 kilometer transect. It seems that maize field diversity is homogenized and field margins had a high beta diversity,” he added.Story Source:The above story is based on materials provided by Entomological Society of America. Note: Materials may be edited for content and length.Read more
Oct. 13, 2013 — Bladder cancer represents a serious public health problem in many countries, especially in Spain, where 11,200 new cases are recorded every year, one of the highest rates in the world. The majority of these tumours have a good prognosis — 70-80% five-year survival after diagnosis — and they do not infiltrate the bladder muscle at the time of diagnosis — in around 80% of cases.Despite this, many of the tumours recur, requiring periodic cytoscopic tumour surveillance. This type of follow-up affects patients’ quality of life, at the same time as incurring significant healthcare costs.Researchers at the Spanish National Cancer Research Centre (CNIO), coordinated by Francisco X. Real, head of the Epithelial Carcinogenesis Group and Nuria Malats, head of the Genetic & Molecular Epidemiology Group, have carried out the first exome sequencing for non-infiltrating bladder cancer, the most frequent type of bladder cancer and the one with the highest risk of recurrence (the exome is the part of the genome that contains protein synthesis information).The results reveal new genetic pathways involved in the disease, such as cellular division and DNA repair, as well as new genes — not previously described — that might be crucial for understanding its origin and evolution.”We know very little about the biology of bladder cancer, which would be useful for classifying patients, predicting relapses and even preventing the illness,” says Cristina Balbás, a predoctoral researcher in Real’s laboratory who is the lead author of the study.The work consisted of analysing the exome from 17 patients diagnosed with bladder cancer and subsequently validating the data via the study of a specific group of genes in 60 additional patients.”We found up to 9 altered genes that hadn’t been described before in this type of tumour, and of these we found that STAG2 was inactive in almost 40% of the least aggressive tumours,” says Real.The researcher adds that: “Some of these genes are involved in previously undescribed genetic pathways in bladder cancer, such as cell division and DNA repair; also, we confirmed and extended other genetic pathways that had previously been described in this cancer type, such as chromatin remodelling.”An Unknown Agent in Bladder CancerThe STAG2 gene has been associated with cancer just over 2 years ago, although “little is known about it, and nothing about its relationship to bladder cancer,” says Balbás. Previous studies suggest it participates in chromosome separation during cell division (chromosomes contain the genetic material), which is where it might be related to cancer, although it has also been associated with maintenance of DNA´s 3D structure or in gene regulation.Contrary to what might be expected, the article reveals that tumours with an alteration in this gene frequently lack changes in the number of chromosomes, which indicates, according to Real, that “this gene participates in bladder cancer via different mechanisms than chromosome separation.”The authors have also found, by analysising tumour tissue from more than 670 patients, that alterations in STAG2 are associated, above all, with tumours from patients with a better prognosis. How and why these phenomena work still needs to be discovered but the researchers predict that “mutations in STAG2 and other additional genes that we showed to be altered could provide new therapeutic opportunities in some patient sub-groups.”Read more
Sep. 9, 2013 — The severity of sleep apnoea can independently predict the aggressiveness of malignant skin melanoma, according to a new study.The research, presented today at the European Respiratory Society (ERS) Annual Congress, adds new evidence to a number of studies that have found a link between cancer and the sleep disorder.Previous studies have looked at a link between sleep apnoea and both mortality and incidence rates from cancer. Some experimental studies in mice have also shown that reduced oxygen levels in the blood, which is common in sleep apnoea, enhanced tumour growth. This is the first study in humans to look at the link between a specific type of cancer (skin melanoma) and sleep apnoea.Researchers studied 56 patients diagnosed with malignant skin melanomas. They measured the aggressiveness of the cancer along with the presence and severity of sleep apnoea.60.7% of the patients had sleep apnoea and 14.3% had severe sleep apnoea. The results found that the melanoma was more aggressive as the severity of sleep apnoea increased. This was the case for all three measurements for sleep apnoea severity. The severity measurements were also linked with other factors of aggressiveness, including the growth rate or the depth of invasion of the tumour.Lead author, Dr Francisco Campos-Rodriguez, from the Hospital de Valme in Seville, Spain, said: “This is the first study in a human sample to show that sleep apnoea can worsen the outcomes of melanoma. The findings are from a preliminary small sample, but if the results are confirmed in larger studies, this would have important clinical implications, particularly as sleep apnoea can be easily treated and this could open up new therapeutic possibilities for people with both conditions. We have just begun a bigger prospective trial enrolling 450 patients with cutaneous melanoma to analyse this link further.”Read more
Aug. 15, 2013 — A new analysis has found that breastfeeding for more than six months may safeguard nonsmoking mothers against breast cancer. The same does not seem to hold true for smoking mothers, though. Published early online in the Journal of Clinical Nursing, the findings add to the list of benefits of breastfeeding for women and their babies.Share This:To look at the relationship between breast cancer and certain aspects of pregnancy and breastfeeding, Emilio González-Jiménez, PhD, of the University of Granada in Spain, and his colleagues analyzed the medical records of 504 female patients who were 19 to 91 years of age and who had been diagnosed and treated for breast cancer from 2004 to 2009 at the San Cecilio University Hospital in Granada. The team looked at factors including age of diagnosis, how long the women breastfed, family history of cancer, obesity, alcohol consumption, and smoking habits.Their analysis revealed that women who underwent childbirth and who breastfed were diagnosed with breast cancer at a later age, regardless of the patients’ family history of cancer. Nonsmokers who breastfed for periods of longer than six months tended to be diagnosed with breast cancer much later in life-an average of 10 years later than nonsmokers who breastfed for a shorter period. In contrast, female smokers were diagnosed with breast cancer at a younger age and obtained no significant benefit from a longer period of breastfeeding.”The results suggest that for nonsmokers, breastfeeding for more than six months not only provides children with numerous health benefits, but it also may protect mothers from breast cancer,” said Dr. González-Jiménez.Share this story on Facebook, Twitter, and Google:Other social bookmarking and sharing tools:|Story Source: The above story is based on materials provided by Wiley, via AlphaGalileo. Note: Materials may be edited for content and length. For further information, please contact the source cited above. …Read more
Aug. 13, 2013 — A gene variant strongly associated with development of type 2 diabetes appears to interact with a Mediterranean diet pattern to prevent stroke, report researchers from the Jean Mayer USDA Human Nutrition Research Center on Aging (USDA HNRCA) at Tufts University and from the CIBER Fisiopatología de la Obesidad y Nutriciόn in Spain. Their results, published online today in Diabetes Care, are a significant advance for nutrigenomics, the study of the linkages between nutrition and gene function and their impact on human health, particularly chronic disease risk.The researchers set out to investigate whether genetics contribute to the cardiovascular benefits seen in the Prevencion con Dieta Mediterranea (PREDIMED) trial. Based in Spain, the randomized, controlled trial enrolled more than 7,000 men and women assigned to either a Mediterranean or low fat control diet and monitored them for cardiovascular disease, stroke and heart attack for almost five years.”Our study is the first to identify a gene-diet interaction affecting stroke in a nutrition intervention trial carried out over a number of years in thousands of men and women,” said senior author José M. Ordovás, Ph.D., director of the Nutrition and Genomics Laboratory at the USDA HNRCA at Tufts University. “The PREDIMED study design provides us with stronger results than we have ever had before. With the ability to analyze the relationship between diet, genetics and life-threatening cardiac events, we can begin to think seriously about developing genetic tests to identify people who may reduce their risk for chronic disease, or even prevent it, by making meaningful changes to the way they eat.”Led by Ordovás and corresponding author Dolores Corella, Ph.D., of the CIBER Fisiopatologia de la Obesidad y Nutriciόn , the researchers focused on a variant in the Transcription Factor 7-Like 2 (TCF7L2) gene, which has been implicated in glucose metabolism but its relationship to cardiovascular disease risk has been uncertain. About 14 percent of the PREDIMED participants were homozygous carriers, meaning they carried two copies of the gene variant and had an increased risk of disease.”Being on the Mediterranean diet reduced the number of strokes in people with two copies of the variant. The food they ate appeared to eliminate any increased stroke susceptibility, putting put them on an even playing field with people with one or no copies of the variant,” explained Ordovás, who is also a professor at the Friedman School of Nutrition Science and Policy at Tufts University. “The results were quite different in the control group following the low fat control diet, where homozygous carriers were almost three times as likely to have a stroke compared to people with one or no copies of the gene variant .”The Mediterranean diet features olive oil, fish, complex carbohydrates and nuts. …Read more
July 26, 2013 — Spanish and Portuguese researchers have discovered that fried fish fingers generate more furanic compounds than those baked in the oven. To be precise, there are three times as many when fried with olive oil and twice as many with sunflower oil. These compounds improve the food’s organoleptic characteristics, but are believed to be toxic and carcinogenic.Worries concerning the presence of furans in food have risen in recent years due to their toxic and carcinogenic effects, as observed in animals. In fact the International Agency for Research on Cancer, part of the WHO, has now listed them as possible carcinogens for humans.Now, a team of researchers from the University of Porto (Portugal) and the University of Extremadura (Spain) has evaluated the effects that the cooking conditions of fish fingers can have on the quantity of furans (furan, 2-furfural, furfuryl alcohol, 2-pentylfuran and 5-hydroxymethylfurfural).The results, published in the journal ‘Food and Chemical Toxicology’, reveal that fish fingers fried in olive oil contain approximately 30 micrograms of furans per gram (µg/g) and around 20 µg/g when sunflower oil is used..When they are oven-baked, on the other hand, they generate fewer of these harmful substances: 10 µg/g. Furthermore, if fried fish fingers are reheated in the microwave, concentrations of 8.15 µg/g are found.”The number of furans is lower when the temperature is lower and frying time is shorter, and also decreases when a longer time elapses after cooking,” explains María Trinidad Pérez-Palacios, one of the authors.Adjust cooking times and conditions”Therefore,” she adds, “formation of furanic compounds can be reduced by adjusting the conditions of cooking and post-cooking, for example by using the oven instead of the deep fryer, lowering the frying time and temperature — 4 minutes at 160 ºC is sufficient — or leaving a suitable amount of time (10 minutes) between cooking the product and eating it.”The researchers found that by following these recommendations the formation of furans can be reduced, although the volatile compounds associated with the aroma and flavour of the cooked products decrease along with them.”Furans enhance the organoleptic characteristics of food, but as there is scientific evidence of their potential toxicity and carcinogenicity, new research is channelled towards reducing the formation of these compounds without impairing our sensory enjoyment of what we are eating,” remarks Pérez-Palacios.There is currently no legislation on the maximum permitted levels of furans in food. The European Food Safety Authority (EFSA) is working on this issue and recommends analysing these substances in heated products, such as cooked foods or drinks such as coffee, both when purchasing and when cooked for consumption.Pérez-Palacios believes that it is also important to educate consumers to read the labels on ready-to-cook food products, which often recommend oven baking as the method of preparation, “which is a positive thing in terms of the results we have found.”As such, manufacturers should also make progress, for example by putting information on packaging relating to the possibility of oven-cooking the product or even recommending it as the sole method of preparation,” the researcher concludes.Read more
July 8, 2013 — Egg donation is now one of the major reasons why couples travel abroad for fertility treatment. Because this growing trend may circumvent regulations at home or raise concerns about financial inducement, it has also become one of the most controversial. Yet little is known about the women who provide the donor eggs in overseas clinics — their characteristics, their motivation and their compensation.A study performed by ESHRE, which surveyed (by questionnaire) 1423 egg donors at 60 clinics in 11 European countries, has now found that the majority of donors are keen to help infertile couples for altruistic reasons, but a large proportion also expect a personal benefit, usually financial.(1,2)The study was performed during 2011 and 2012 by ESHRE’s Task Force on Cross-border Reproductive Care and European IVF Monitoring Consortium, with the results presented today by the chairman of the Task Force, Professor Guido Pennings of the Bioethics Institute Ghent, Belgium. The donor’s age proved an important factor in her motivation to donate. While the overall average age of the donors in this study was relatively young (27.4 years, ranging from 25.6 in Spain to 31 years in France), there was a significant effect of age on altruistic motives: 46% of the donors under 25 noted altruism alone as their motive compared to 79% of those over 35; 12% of those under 25 were purely financially motivated compared to 1% of those older than 35. The younger you are, apparently, the more is money a motivation.Among the donor groups identified in the study population were:Students (18% in Spain, 16% Finland, 13% Czech Republic) Unemployed (24% in Spain, 22% Ukraine, 17% Greece) Fully employed (75% in Belgium, 70% Poland, 28% Spain) Single women (50%+ in Spain and Portugal, 30% Greece) Other findings showed that around one-third of all study donors had a university degree, and around one half all donors had a child of their own. Why do donors go through a demanding IVF treatment cycle to donate eggs? The study firstly found that, while altruism was the principal motive overall, the majority of donors did receive financial compensation. “The fact that a person receives compensation or money does not mean that she is motivated by that money,” said Professor Pennings. However, the study made it clear that financial compensation is still an important motivation for many donors, especially in certain countries. …Read more
July 4, 2013 — Milk from organic farms has a lower concentration of elements like zinc, iodine and selenium than milk produced by conventional farming methods. The discrepancy is due to the absence of mineral substances in the diets of the cows reared. According to researchers, animals on organic farms should have their diets supplemented with natural sources of iodine such as seaweed, because it is a very important element for children and pregnant women.The concentration of nutrients in animal food products is linked to the diets of the animals reared. Conventional production methods provide mineral diet supplements, while in organic farming animals depend on the mineral content in soil, which may not be sufficient.For this reason, researchers at the University of Santiago de Compostela compared the mineral and toxic elements of organic and conventional milk taken from over thirty farms located in the northeast of the Iberian Peninsula.The results demonstrated that mineral element content in organic milk is low compared with conventional milk, although no differences were found in the quantity of toxic compounds such as cadmium, which were also detected in very low concentrations.”Levels of the elements that are typically supplemented in the diets of livestock in conventional systems — particularly iodine, copper, selenium and zinc — are higher than those found in organic milk,” Marta López, researcher at the University of Santiago de Compostela and co-author of the study, explains.In the researcher’s opinion, the fact that organic milk contains lower levels of elements such as copper and zinc is not a problem because milk is not the primary source of these elements in our diets.”Iodine is another matter,” López goes on to clarify. “The contribution of iodine to our diets in countries like Spain is covered by iodised salt; in other countries, like England, with milk. In Spain the lack of sufficient iodine in some kinds of milk is especially relevant for children, due to the importance of iodine in neurological development, but also to people with diets low in salt.”Iodine is necessary for the metabolism, especially during pregnancy and infancy. Iodine deficiency can cause scurvy, which has historically been a big problem the world over, particularly in populations at a distance from the coast, who did not eat much fish, and so milk and its derivatives were the primary source of iodine.Seaweed as an alternative sourceNevertheless, according to López, the most relevant aspect of the study is that it brings this limitation to light and enables organic production to be improved. “There are natural sources of iodine that can be incorporated into the diet. We are trialling the use of seaweed as a source of iodine and have had good results,” she affirms.In addition, the scientists found that mineral content is higher in winter, which is when dietary supplementation is greater, as a result of the reduced availability of grass.In any case, although one might draw the conclusion that conventional milk is more nutritious in terms of minerals, López is cautious: “Organic milk may have lower content of certain minerals, but it has other properties that are much more beneficial than those of conventional milk.”Read more
July 3, 2013 — Researchers from the University of Oviedo (Spain) have labelled sulfur in brewer’s yeast with a non-radioactive method so that when feeding it to laboratory rats the course taken by the element can be tracked and the amino acids and proteins analysed at the point of incorporation. The technique could be very useful for studying the metabolism of this micro-nutrient in vivo and verifying how sulfur-based drugs behave in the organism.Until now scientists have studied the metabolism of sulfur, an essential element in all living organisms, using radioactive isotopes, particularly sulfur-35. But now scientists from the University of Oviedo have come up with a technique to do this with a stable, non-radioactive isotope: namely, sulfur-34.”The presence of sulfur is particularly notable in the composition of cysteine and methionine, two amino acids fundamental to the formation of animal proteins,” explained Justo Giner Martínez-Sierra, Doctor of Chemistry at the University of Oviedo and co-author of the study. “And it is truly innovative to have a methodology that enables us to follow the course of this element without running the risk of radiation.”The process begins by labelling brewer’s yeast (Saccharomyces cerevisiae) with this innocuous stable isotope then feeding it to laboratory rats. The researchers ensure that the rodents eat all the yeast using a nasogastric tube.Once the labelled sulfur begins to be incorporated into the peptides (chains of amino acids) and the animal proteins, the scientists can detect and isolate small concentrations of it using a hybrid technique combining separation and detection by mass spectrometry (HPLC-ICP-MS). In this way the isotope can be tracked in protein compounds.”Among its applications are the majority of fundamental studies on the basic metabolism of sulfur and its amino acids, studies on protein synthesis and degradation (“protein turnover”) and research on pharmacokinetics and the metabolism of drugs and medicines containing sulfur in their structure,” Giner goes on.sulfur is an essential micronutrient, or trace element, for all living organisms. As well as cysteine and methionine, it is present in other amino acids such as taurine and homocysteine, as well as in a number of compounds of great biological importance like coenzyme A or vitamins B1 (thiamine) and B7 (biotin).Only four naturally-occurring sulfur isotopes are stable: sulfur-32, 33, 34 and 36. The majority isotope is sulfur-32 with approximately a 94.93% abundance in animal tissues. The low isotopic abundance of the others, for example sulfur-34 (present in 4.29%), makes them suitable for use as tracers, in other words, sulfurs that are identical to the original in chemical and functional terms but which can be differentiated and detected specifically by mass spectrometry techniques.Mammals are incapable of synthesising sulfur-containing amino acids and need to obtain them from food, for example from meat, fish, dairy products, eggs or nuts.The researchers have taken advantage of the ability of yeasts to convert the inorganic sulphate into organosulfur compounds. In particular, the choice of Saccharomyces cerevisiae is prompted by its high rates of cell growth and its safety, as it is classed a safe microorganism for human health by the USA’s Food and Drug Administration (FDA).Read more
June 26, 2013 — A team of astronomers from the UK, Germany and Spain have observed the remnant of a stellar collision and discovered that its brightness varies in a way not seen before on this rare type of star. By analysing the patterns in these brightness variations, astronomers will learn what really happens when stars collide.Share This:This discovery will be published in the 27 June 2013 issue of the journal Nature.Stars like our Sun expand and cool to become red giant stars when the hydrogen that fuels the nuclear fusion in their cores starts to run out. Many stars are born in binary systems so an expanding red giant star will sometimes collide with an orbiting companion star. As much as 90% of the red giant star’s mass can be stripped off in a stellar collision, but the details of this process are not well understood. Only a few stars that have recently emerged from a stellar collision are known, so it has been difficult to study the connection between stellar collisions and the various exotic stellar systems they produce. When an eclipsing binary system containing one such star turned up as a by-product of a search for extrasolar planets, Dr Pierre Maxted and his colleagues decided to use the high-speed camera ULTRACAM to study the eclipses of the star in detail. These new high-speed brightness measurements show that the remnant of the stripped red giant is a new type of pulsating star.Many stars, including our own Sun, vary in brightness because of pulsations caused by sound waves bouncing around inside the star. For both the Sun and the new variable star, each pulsation cycle takes about 5 minutes. These pulsations can be used to study the properties of a star below its visible surface. Computer models produced by the discovery team show that the sound waves probe all the way to the centre of the new pulsating star. …Read more
June 14, 2013 — The protection provided by the smoking ban decreases when people can still smoke outside the venue.For the first time, a study has analysed the effects of the modification to the Spanish tobacco control law, implemented in 2011 in hospitality venues in Spain. The findings show that smoking on terraces and in the entrances to bars and restaurants increases the concentration of nicotine and particulate matter, which affects clients and hospitality professionals alike.Smoke in bars would appear to be a thing of the past. However, Spanish scientists have analysed the reduction of nicotine in hospitality venues since the implementation of the 2011 smoking ban, and have found that smoking outside diminishes such protection.”Having studied hospitality venues in Madrid, Galicia and Catalonia, we found a 90% decrease in the presence of nicotine and particulate matter in suspension, attributable to the regulations that have been in place for the last two years,” explained Maria José López, the main author of the article and researcher at the Barcelona Public Health Agency (ASPB).This latest research, published in Nicotine & Tobacco Research, detected more nicotine and increased presence of particles in bars where clients smoked outside, which acts as a warning to experts on risks associated with incomplete protection for employees and customers.The results compare the situation in the same establishments before and after the change to the law that took place in January 2011, based on 351 nicotine measurements carried out and a total of 160 samples of particles under 2.5 µ.The mean concentration of nicotine in the atmosphere in venues with smokers outside was 1.13 µg/cubic meter (m3), while in those where this option is not available there were only 0.41 µg/m3.The authors also recorded other factors such as the presence of ashtrays, people smoking, and whether there were remnants of cigarette butts in the venue.An overall decreaseThe authors confirm that the 90% reduction in the presence of nicotine and particulate matter corresponds to the findings of similar studies in other European countries, such as Scotland and Ireland.”The same occurred in Uruguay, where implementation of the law led to a 91% reduction in the presence of secondary smoke in catering venues,” López affirms.The previous law in 2006 did not protect customers from second-hand smoke exposure, and even created inequalities, allowing hospitality workers to remain exposed to high levels of toxins and carcinogens.”The 2011 modification of the law represents an extraordinary step forward in the protection of workers’ and clients’ health,” López concludes. Although she insists that “the levels of exposure in outside areas should be studied in more detail and the potential need to establish consumption restrictions in certain places should be considered.”This study, undertaken by a work group on Nicotinism at the Spanish Society of Epidemiology, was made possible by the financial backing of the Ministry of Health, Social Services and Equality, the Department of Health of the Regional Government of Catalonia, and the National Centre for Epidemiology (Carlos III Health Institute).The authors wish to extend a special mention in memory of Manel Nebot, the driving force behind research on nicotinism in Spain, who passed away last October in Barcelona.Read more
June 11, 2013 — Spanish and US scientists have successfully identified animal species that can transmit more diseases to humans by using mathematical tools similar to those applied to the study of social networks like Facebook or Twitter. Their research — recently published in the journal PNAS — describes how parasite-primate interactions transmit diseases like malaria, yellow fever or AIDS to humans. Their findings could make an important contribution to predicting the animal species most likely to cause future pandemics.Professor José María Gómez of the University of Granada Department of Ecology is the principal author of this research, in collaboration with Charles L. Nunn (University of Cambridge, Massachusetts, US) and Miguel Verdú (Spanish National Research Council Desertification Research Center, Valencia, Spain). They propose a criterion to identify disease-transmission agents based on complex network metrics similar to those used to study social networks.As Prof Gómez explains, “most emerging diseases in humans are zoonotic, that is, they are transmitted to humans by animals. To identify animal species that are potential high-risk sources of emerging diseases it’s essential we set up mechanisms that control and observe these diseases.”Study of 150 primate speciesTo conduct their study, the researchers constructed a network in which each node represented one of the approximately 150 non-human primate species about which we have enough data on their parasite fauna. “Each primate species is connected to the other primates as a function of the number of parasites they share. Once the network was constructed, we studied each primate species’ position — whether central or peripheral. A primate’s centrality is measured by its connection intensity with many other primates that are, in turn, closely connected,” says the University of Granada researcher.The article published in PNAS reports the researchers’ discovery that the most central primates could be more capable of transmitting parasites to other species and, therefore, to humans, than the rest. “This is comparable to the idea that, in social networks, web pages that are central and have links to many other pages, spread their contents all through the Web,” José María Gómez affirms.The researchers have confirmed their hypothesis by relating the centrality value of each primate with the number of emerging pathogens shared with humans. …Read more
June 7, 2013 — Researchers from the University of Granada (Spain) have analysed the presence of patulin, a type of toxin produced by fungi, in several commercial apple juices. The results show that more than 50% of the samples analysed exceed the maximum limits laid down by law. They have also discovered a sample of rice with more mycotoxins than permitted. For their part, researchers from the University of Valencia have also found these harmful substances in beers, cereals and products made from them, such as gofio flour.They are not very well known, but mycotoxins top the list of the most widespread natural contaminants in foodstuffs at the global level. They are toxic and carcinogenic substances produced by fungi, which reach the food chain through plants and their fruit. Now new analytical techniques developed in universities such as Granada and Valencia (Spain) show that some foodstuffs exceed permitted levels of these harmful compounds.Researchers from the University of Granada (UGR) have used their own method of ‘microextraction and capillary electrophoresis’ to analyse concentrations of a kind of mycotoxins, patulin, in 19 batches of eight brands of commercial apple juice. They differentiated between conventional juice, organic juice and juice designed specifically for children.”The results show that more than 50% of the samples analysed exceeded the maximum contents laid down by European law,” as explained by Monsalud del Olmo, co-author of the study, which is published this month in the magazine ‘Food Control’.The maximum levels of patulin established by the EU are 50 micrograms per kilogram of product (μg/kg) for fruit juices and nectars, 25 μg/kg for compotes and other solid apple products and 10 μg/kg if those foodstuffs are aimed at breast-fed babies and young children.However, some samples of conventional apple juices had as much as 114.4 μg/kg, and one batch labelled as baby food had 162.2 μg/kg, more than 15 times the legal limit.Patulin is produced by several species of fungi of the Penicillium, Aspergillus and Byssochylamys varieties, which are found naturally in fruit, mainly apples. They are transferred to juices during processing because of their solubility in water and stability.The neurotoxic, immunotoxic and mutagenic effects of this substance have been confirmed in animal models. “Even then, it is not one of the most dangerous mycotoxins for health and it is included in group 3 within the categories laid down by the International Agency for Research on Cancer (IARC),” Monsalud del Olmo pointed out.This WHO agency classifies mycotoxins and other compounds in four groups according to their carcinogenic potential for humans: 1 (carcinogenic), 2 (probably or possibly carcinogenic), 3 (not classifiable as carcinogenic, although it has not been proven that it is not) and 4 (probably not carcinogenic).Some mycotoxins, such as aflatoxins, are in group 1 and can be found in dry fruit, such as peanuts and pistachios, and cereals. UGR scientists have also detected concentrations of this compound above the permitted levels in a sample of rice, and they have already informed the relevant authorities of this.Other toxins from fungi, such as fumonisins and ochratoxins, are also included in group 2. …Read more
May 10, 2013 — Our ability to assess biological diversity, ecosystem health, ecological interactions, and a wide range of other important processes is largely dependent on accurately recognizing species. However, identifying and describing species is not always a straightforward task. In some cases, a single species may show a high level of morphological variation, while in other cases, multiple morphologically similar species may be hidden under a single species name. Cryptic species, two or more distinct species that are erroneously classified under a single species name, are found in all major groups of living things.
As an alternative to traditional morphology-based species delimitation, an international research group, including scientists from Germany, Iran, Spain, and the USA, describe five new species of lichen-forming fungi from what was traditionally considered a single species using differences in DNA sequence data. The authors state that “the effective use of genetic data appears to be essential to appropriately and practically identify natural groups in some phenotypically cryptic lichen-forming fungal lineages.”
The study was published in the open access journal Mycokeys.
They also provide a reference DNA sequence database for specimen identification using DNA barcoding, making specimen identification more accessible and more reliable at the same time. The application of DNA-based identification can potentially be used as a way for both specialists and nonspecialists alike to recognize species that are otherwise difficult to identify.
Lichens are commonly used to monitor ecosystem health and the impact of atmospheric pollution. In addition, some lichens are potentially valuable sources of pharmaceutical products, including antibiotics, antioxidants, etc. In spite of their occurrence in all terrestrial ecosystems and overall ecological importance, lichens are commonly overlooked. DNA barcode identification can be performed in a variety of ecological, pharmaceutical, and biomonitoring studies in order to quickly sort specimens into the correct species.
The authors argue that the use of molecular sequence data in identifying species will likely become increasingly important and routinely applied. Other disciplines such as ecology, conservation, and physiology will benefit from a more objectively based species circumscription, enabling us to interpret distribution and ecological patterns more precisely, while more accurately monitoring environmental disturbance and climate change. The authors predict that this approach will prove to be an important tool in making critical conservation-related decisions.
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- Steven Leavitt, Fernando Fernández-Mendoza, Sergio Pérez-Ortega, Mohammad Sohrabi, Pradeep Divakar, Thorsten Lumbsch, Larry St. Clair. DNA barcode identification of lichen-forming fungal species in the Rhizoplaca melanophthalma species-complex (Lecanorales, Lecanoraceae), including five new species. MycoKeys, 2013; 7 (0): 1 DOI: 10.3897/mycokeys.7.4508
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Apr. 24, 2013 — Ants play a variety of important roles in many ecosystems. As frequent visitors to flowers, they can benefit plants in their role as pollinators when they forage on sugar-rich nectar. However, a new study reveals that this mutualistic relationship may actually have some hidden costs. By transmitting sugar-eating yeasts to the nectar on which they feed, ants may be indirectly altering the nectar-chemistry and thus affecting subsequent pollinator visitations.
Many species of plants benefit from interacting with ants, and some even secrete special sugary substances to attract ants. Plants produce sugar, in the form of nectar, and in exchange ants provide services such as pollination or protection from herbivores.
The main components of nectar that attract pollinators include three dominant sugars — sucrose, fructose, and glucose — and amino acids (or proteins). The chemical composition of nectar differs among plant species and has been thought to be a conservative trait linked to pollinator type. For example, plants pollinated by hummingbirds tend to have nectar with high amounts of sucrose. In addition, nectar composition is thought to be regulated by the plant.
“When people think about how flowers are pollinated, they probably think about bees,” notes Clara de Vega, a postdoctoral researcher at the Estación Biológica de Doñana, Spain. “But ants also pollinate flowers, and I am interested in the role ants play in pollination since it is still poorly understood.”
De Vega joined forces with Carlos M. Herrera, an evolutionary ecologist at the Estación Biológica de Doñana, to investigate the relationship between ant pollinators and nectarivorous yeasts. Nectar-dwelling yeasts, which consume sugars, have recently been discovered in the flowers of many temperate and tropical plant species. De Vega and Herrera have already discovered that some ant species not only carry certain types of sugar-metabolizing yeasts on their bodies, but they also effectively transmit these yeasts to the nectar of flowers they visit.
In their most recent work, published in the American Journal of Botany, De Vega and Herrera investigated whether flowers visited by these ants differed from flowers that were not visited by ants in their sugar chemistry, and whether sugar-chemistry was correlated with the abundance of ant-transmitted yeasts found in the nectar.
By excluding ants from visiting inflorescences of a perennial, parasitic plant, Cytinus hypocistis, and comparing the nectar chemistry to inflorescences that were visited by ants, the authors tested these ideas experimentally.
When the authors compared the sugar content in the nectar of flowers visited by ants versus those enclosed in nylon mesh bags to exclude ants, they found that nectar of flowers exposed to ants had higher levels of fructose and glucose, but lower levels of sucrose compared with the ant-excluded flowers.
Interestingly, in flowers visited by ants, there was a high correlation between yeast cell density and sugar content. Nectar that had higher densities of yeast had more fructose and less sucrose, suggesting that the types of yeasts change the sugar content of the nectar. Flowers that were excluded from ants did not have any yeast in their nectar.
“Our study has revealed that ants can actually change the nectar characteristics of the flowers they are pollinating,” says de Vega. “The microorganisms, specifically yeasts, that are present on the surface of ants change the composition of sugar in the flower´s nectar.”
“This means that nectar composition is not completely controlled by the flower — it is something created in cooperation with the ants that visit the flower,” she notes. “We also think that these ant-transported yeasts might have the potential to affect plant reproduction.”
Indeed, if a plant cannot control the sugar content of its nectar, then it may lose some of its target pollinators, which would potentially affect overall seed set and plant fitness.
Moreover, if introducing these yeasts to nectar changes the chemistry of the very components that serve to attract pollinators, then perhaps ants are indirectly changing the foraging behavior of subsequent flower visitors and thereby affecting seed dispersal patterns.
This study has revealed an additional layer in the complex association between ants and flowering plants, as pollinating ants alter sugar-nectar chemistry in flowers via sugar-consuming yeasts. But the story does not end here. De Vega plans to continue researching the role that these nectarivorous yeasts play on the reproduction of plants.
“I plan to study the whole interaction of plants, yeasts, and pollinators — how are they interrelated and what mechanisms shape these relations?”Read more
Apr. 25, 2013 — The European Union cannot meet its goals in agricultural policy without embracing genetically engineered crops (GMOs). That’s the conclusion of scientists who write in Trends in Plant Science, a Cell Press publication, based on case studies showing that the EU is undermining its own competitiveness in the agricultural sector to its own detriment and that of its humanitarian activities in the developing world.
“Failing such a change, ultimately the EU will become almost entirely dependent on the outside world for food and feed and scientific progress, ironically because the outside world has embraced the technology which is so unpopular in Europe, realizing this is the only way to achieve sustainable agriculture,” said Paul Christou of the University of Lleida-Agrotecnio Center and Institució Catalana de Recerca i Estudis Avançats in Spain.
“Many aspects of the EU agricultural policy, including those concerning GMOs, are internally inconsistent and actively obstruct what the policy sets out to achieve,” Christou and his colleagues continued.
For instance, the Lisbon Strategy aims to create a knowledge-based bioeconomy and recognizes the potential of GMOs to deliver it, but EU policy on the cultivation of GMOs has created an environment that makes this impossible. In reality, there is a de facto moratorium in Europe on the cultivation of genetically engineered crops such as maize, cotton, and soybean, even as the same products are imported because there is insufficient capacity to produce them by conventional means at home.
Subsidies designed to support farmers now benefit large producers at the expense of family farms, Christou says. The EU has also banned its farmers from using many pesticides and restricted them from other nonchemical methods of pest control, while allowing food products produced in the same ways to be imported.
“EU farmers are denied freedom of choice — in essence, they are prevented from competing because EU policies actively discriminate against those wishing to cultivate genetically engineered crops, yet exactly the same crops are approved for import,” Christou says.Read more