1,213 research outputs found
Reconfigurable Carbon Nanotube Multiplexed Sensing Devices
Here
we report on the fabrication of reconfigurable and solution
processable nanoscale biosensors with multisensing capability, based
on single-walled carbon nanotubes (SWCNTs). Distinct DNA-wrapped (hence
water-soluble) CNTs were immobilized from solution onto different
prepatterned electrodes on the same chip, via a low-cost dielectrophoresis
(DEP) methodology. The CNTs were functionalized with specific, and
different, aptamer sequences that were employed as selective recognition
elements for biomarkers indicative of stress and neuro-trauma conditions.
Multiplexed detection of three different biomarkers was successfully
performed, and real-time detection was achieved in serum down to physiologically
relevant concentrations of 50 nM, 10 nM, and 500 pM for cortisol,
dehydroepiandrosterone-sulfate (DHEAS), and neuropeptide Y (NPY),
respectively. Additionally, the fabricated nanoscale devices were
shown to be reconfigurable and reusable via a simple cleaning procedure.
The general applicability of the strategy presented, and the facile
device fabrication from aqueous solution, hold great potential for
the development of the next generation of low power consumption portable
diagnostic assays for the simultaneous monitoring of different health
parameters
Influence of shear stress magnitude and direction on atherosclerotic plaque composition
British Heart Foundation (BHF) grants (no. RG/11/13/29055 and PG/15/49/31595), awarded to R.K. and E.P. who are employed by Bioengineering and the MRC Clinical Sciences
Centre at Imperial College London. The grants also supported R.M.P. and S.M.B. V.V.M. was supported by a BHF. PhD studentship
Antagonistic Bacterial Interactions Help Shape Host-Symbiont Dynamics within the Fungus-Growing Ant-Microbe Mutualism
Conflict within mutually beneficial associations is predicted to destabilize relationships, and theoretical and empirical work exploring this has provided significant insight into the dynamics of cooperative interactions. Within mutualistic associations, the expression and regulation of conflict is likely more complex than in intraspecific cooperative relationship, because of the potential presence of: i) multiple genotypes of microbial species associated with individual hosts, ii) multiple species of symbiotic lineages forming cooperative partner pairings, and iii) additional symbiont lineages. Here we explore complexity of conflict expression within the ancient and coevolved mutualistic association between attine ants, their fungal cultivar, and actinomycetous bacteria (Pseudonocardia). Specifically, we examine conflict between the ants and their Pseudonocardia symbionts maintained to derive antibiotics against parasitic microfungi (Escovopsis) infecting the ants' fungus garden. Symbiont assays pairing isolates of Pseudonocardia spp. associated with fungus-growing ants spanning the phylogenetic diversity of the mutualism revealed that antagonism between strains is common. In contrast, antagonism was substantially less common between more closely related bacteria associated with Acromyrmex leaf-cutting ants. In both experiments, the observed variation in antagonism across pairings was primarily due to the inhibitory capabilities and susceptibility of individual strains, but also the phylogenetic relationships between the ant host of the symbionts, as well as the pair-wise genetic distances between strains. The presence of antagonism throughout the phylogenetic diversity of Pseudonocardia symbionts indicates that these reactions likely have shaped the symbiosis from its origin. Antagonism is expected to prevent novel strains from invading colonies, enforcing single-strain rearing within individual ant colonies. While this may align ant-actinomycete interests in the bipartite association, the presence of single strains of Pseudonocardia within colonies may not be in the best interest of the ants, because increasing the diversity of bacteria, and thereby antibiotic diversity, would help the ant-fungus mutualism deal with the specialized parasites
Seasonal variations of Saanen goat milk composition and the impact of climatic conditions
The aim of this research was to investigate the effect of climatic conditions and their impact on seasonal variations of physico-chemical characteristics of Saanen goat milk produced over a period of 4 years. Lactation period (early, mid and late) and year were considered as factors that influence physico-chemical composition of milk. Pearson's coefficient of correlation was calculated between the physico-chemical characteristics of milk (fat, proteins, lactose, non-fat dry matter, density, freezing point, pH, titrable acidity) and climatic condition parameters (air temperature, temperature humidity index-THI, solar radiation duration, relative humidity). Results showed that all physico-chemical characteristics of Saanen goat milk varied significantly throughout the lactation period and years. The decrease of fat, protein, non-fat dry matter and lactose content in goat milk during the mid-lactation period was more pronounced than was previously reported in the literature. The highest values for these characteristics were recorded in the late lactation period. Observed variations were explained by negative correlation between THI and the physico-chemical characteristics of Saanen goat milk. This indicated that Saanen goats were very prone to heat stress, which implied the decrease of physico-chemical characteristics during hot summers
Relationship between periodontitis and rheumatoid arthritis and the effect of non-surgical periodontal treatment
Advances in prevention and therapy of neonatal dairy calf diarrhoea : a systematical review with emphasis on colostrum management and fluid therapy
Neonatal calf diarrhoea remains the most common cause of morbidity and mortality in preweaned dairy calves worldwide. This complex disease can be triggered by both infectious and non-infectious causes. The four most important enteropathogens leading to neonatal dairy calf diarrhoea are Escherichia coli, rota-and coronavirus, and Cryptosporidium parvum. Besides treating diarrhoeic neonatal dairy calves, the veterinarian is the most obvious person to advise the dairy farmer on prevention and treatment of this disease. This review deals with prevention and treatment of neonatal dairy calf diarrhoea focusing on the importance of a good colostrum management and a correct fluid therapy
IL-33 Induces IL-9 Production in Human CD4+ T Cells and Basophils
IL-33, an IL-1 family member and ligand for the IL-1 receptor-related protein ST2, has been associated with induction of Th2 cytokines such as IL-4, IL-5, and IL-13. Here, we report that IL-33 can initiate IL-9 protein secretion in vitro in human CD4+ T cells and basophils isolated from peripheral blood. TGF-β has been described as a critical factor for IL-9 induction in Th2 cells; however, we found that TGF-β also induces co-production of IL-9 in purified, naïve (>99%) CD4+CD45RA+CD45RO−CD25− T cells differentiated towards a Th1 profile. Subsequently, it was demonstrated that TGF-β is important, although not an absolute requirement, for IL-9 production in CD4+ T cells. IL-9 production by purified (>95%) human basophils, cultured for 24 h with IL-3 or IL-33, was found, with a strong synergy between the two, likely to be explained by the IL-3 upregulated ST2 expression. Collectively, these data indicate that barrier functioning cells are important for the regulation of IL-9 production by immune cells in inflamed tissue
Safety of betaine as a novel food pursuant to Regulation (EC) No 258/97
Following a request from the European Commission, the EFSA Panelon Dietetic Products, Nutrition and Allergies (NDA) was asked to deliver an opinion on betaine as a novel food (NF) pursuant to Regulation (EC) No 258/97. The information provided on the composition, the specifications, the batch-to-batch variability, stability and production process of the NF is sufficient and does not raise concerns about the safety of the NF. The NF is proposed to be used in foods intended to meet additional requirements for intense muscular effort with a maximum intake of 2.5 g/day of betaine for sports people above 10 years of age. Based on the lowest BMDL05, which was derived from a chronic toxicity study in rats in which a dose-related increase in platelet counts was observed, and the anticipated daily intake of the NF in the target population, the Margins of Exposure are 3.6 and 5, which are generally regarded as not sufficient. However, the total exposure to betaine from the diet (about 830 mg/day) is not known to be associated with adverse effects. Moreover, no adverse effects on platelet counts were noted in human intervention studies with exposure levels of 4 g/day of betaine for up to 6 months. A significant increase in total and low-density lipoprotein (LDL)-cholesterol concentrations was noted at intakes of 4 g/day of betaine in overweight subjects with metabolic syndrome but not in healthy subjects, nor at intakes of 3 g/day. Thus, considering 4 g/day of betaine as a reference point and applying an uncertainty factor of 10 to account for interindividual variability, an amount of 400 mg/day of betaine in addition to the background exposure is considered as safe. The Panelconsiders that the NF is safe to be used at maximum intake of 400 mg/day in the target population
Statement on the safety of taxifolin-rich extract from Dahurian Larch (Larix gmelinii)
Following a request from the European Commission, the EFSA Panelon Dietetic Products, Nutrition and Allergies (NDA) was asked to carry out a supplementary safety assessment for taxifolin by considering also those population groups which were originally excluded at the request of the applicant (i.e. infants, young children and children up to 9 years) for the food categories set out in the application, and by taking into the extension of use of taxifolin from yogurt to a wider range of dairy products. In 2016, the EFSA NDA Paneladopted the Scientific Opinion on the safety of taxifolin-rich extract from Dahurian Larch (Larix gmelinii) as a novel food ingredient in non-alcoholic beverages, yogurts, chocolate confectionery and food supplements pursuant to Regulation (EC) No 258/97. In order to address the present mandate, an intake assessment was carried out by taking into account all population groups (including now also children below 9years of age) and by considering the food intended categories for which the applicant provided maximum use levels of taxifolin. Intakes were estimated for all age groups of the general population. The highest 95 th percentile intakes per kg bw per day among all population groups are 0.94 and 1.54 mg, respectively, derived for toddlers. Noting that the no-observed-adverse effect level (NOAEL) of the subchronic study was 1,500 mg/kg body weight (bw), the resulting margin of exposure (MOE) would be almost 1,000. For adults weighing 70 kg, the MOE to the combined intake from fortified foods and food supplements would be about 772. For adolescents, taking into account a default mean body weight of 61 kg, the MOE to the combined intake (including 100 mg from food supplements) would be about 627. The Panelconsiders that these MOEs are sufficient. The Panelconcludes that the NF food, taxifolin-rich extract from Dahurian Larch, is safe under the proposed conditions of use
Safety of Ecklonia cava phlorotannins as a novel food pursuant to Regulation (EC) No 258/97
Following a request from the European Commission, the EFSA Panelon Dietetic Products, Nutrition and Allergies (NDA) was asked to deliver a scientific opinion on the safety of Ecklonia cava phlorotannins (marketed as SeaPolynol) as a novel food submitted pursuant to Regulation (EC) No258/97. The novel food is a phlorotannin-rich alcohol extract of Ecklonia cava, which is an edible marine brown alga species. The information provided on the composition, the specifications, the production process and the batch-to-batch variability of the novel food is sufficient and does not raise safety concerns. The intention is to market the novel food as a food supplement for healthy individuals over the age of 12years. A subchronic repeated dose oral toxicity study in rodents tested the novel food at daily doses of 0, 375, 750 and 1,500mg/kg body weight (bw). The Panelconsiders the mid-dose as the no-observed-adverse-effect-level (NOAEL) of the study. Taking into account this NOAEL of 750mg/kg bw per day and by applying an uncertainty factor of 200, the Panelconsiders an intake level of 3.75mg/kg bw per day as safe. The Panelconcludes that the novel food, Ecklonia cava phlorotannins, is safe for the use in food supplements at a maximum daily intake level of 163mg/day for adolescents from 12 to 14years of age, 230mg/day for adolescents above 14years of age and 263mg/day for adults. (C) 2017 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority
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