254 research outputs found
Duplication of clostridial binding domains for enhanced macromolecular delivery into neurons
Neurological diseases constitute a quarter of global disease burden and are expected to rise worldwide with the ageing of human populations. There is an increasing need to develop new molecular systems which can deliver drugs specifically into neurons, non-dividing cells meant to last a human lifetime. Neuronal drug delivery must rely on agents which can recognise neurons with high specificity and affinity. Here we used a recently introduced ‘stapling’ system to prepare macromolecules carrying duplicated binding domains from the clostridial family of neurotoxins. We engineered individual parts of clostridial neurotoxins separately and combined them using a strong alpha-helical bundle. We show that combining two identical binding domains of tetanus and botulinum type D neurotoxins, in a sterically defined way by protein stapling, allows enhanced intracellular delivery of molecules into neurons. We also engineered a botulinum neurotoxin type C variant with a duplicated binding domain which increased enzymatic delivery compared to the native type C toxin. We conclude that duplication of the binding parts of tetanus or botulinum neurotoxins will allow production of high avidity agents which could deliver imaging reagents and large therapeutic enzymes into neurons with superior efficiency
Anaphylaxis to hyperallergenic functional foods
<p>Abstract</p> <p>Background</p> <p>Food allergy can cause life threatening reactions. Currently, patients with severe food allergy are advised to avoid foods which provoke allergic reactions. This has become increasingly difficult as food proteins are being added to a broader range of consumer products.</p> <p>Patients and methods</p> <p>Here we describe our investigations into the allergenicity of a new drink when two cow's milk allergic children suffered anaphylaxis after consuming <it>Wh</it><sub><it>2</it></sub><it>ole</it><sup>®</sup>.</p> <p>Results</p> <p>Our studies have shown that in comparison with cow's milk, <it>Wh</it><sub><it>2</it></sub><it>ole</it><sup>® </sup>contains at least three times the concentration of β-lactoglobulin. β-lactoglobulin is one of the dominant allergens in bovine milk.</p> <p>Conclusions</p> <p>These studies have shown that modern technology allows the creation of "hyperallergenic" foods. These products have the potential to cause severe reactions in milk allergic persons. Avoiding inadvertent exposure is the shared responsibility of allergic consumers, regulatory authorities and the food industry.</p
Immunochemical investigation of allergenic residues in experimental and commercially-available wines fined with egg white proteins
Proteinaceous egg whites are widely used as a fining agent during the production of red wines. Residues of egg white in the final wine could present a risk for individuals allergic to eggs. This study investigated the presence of allergenic residues in both red and white wines fined with egg whites. Experimental and commercially available wines fined with egg whites, with or without subsequent bentonite fining, were studied. Unfined wines were used as negative controls. The physicochemical characteristics of each wine were determined to assess their possible role in enhancing or hindering the elimination of allergenic residues from wine. The amount of egg white protein residues was investigated both by a specifically developed/validated ELISA test and by immunoblotting. Both immunochemical tests used the same anti-total egg white protein antibody and were highly sensitive to the allergen. No egg white protein was detected in the wines studied in either immunochemical test, irrespective of the physicochemical characteristics of the wine, the type and dosage of the fining agent and the oenological process used. The risk of adverse reactions in egg-allergic individuals should therefore be considered negligible, but the exemption from labelling should be allowed only when the absence of residues is confirmed by analytical controls. \ua9 2014 Elsevier Ltd. All rights reserved
The PlantLIBRA consumer survey: Findings on the use of plant food supplements in Italy
Background
Food supplements, and in particular those containing botanicals (plant food supplements, PFS), have in recent decades been of great interest both to consumers and to food/pharmaceutical industries.
Objectives
The aim of this paper is to examine replies by Italian consumers to the PlantLIBRA consumers' survey in order to: 1) assess the behaviour of an Italian population with respect to the use of PFS, and to compare it with that of other 5 countries involved in the whole survey; 2) identify different habits in the 4 Italian cities selected according to their geographical distribution; 3) collect independent information on the actual intake of PFS and consumers' behaviour.
Subjects/setting
397 Italian consumers enrolled, 187 males (49.5%) and 191 female (50.5%). The distribution of subjects among the 4 cities included was: Milan 99; Venice 90; Rome 96 and Catania 96.
Results
The interest in PFS in Italy is high, the prevalence of "regular" consumers being 22.7%. Some differences were observed between the 4 cities involved: the pattern of use during the year was specific to each city; consumers in Milan reported reasons to use PFS significantly different from those in the whole Italian sample and did not indicate supermarkets as an important place of purchase; respondents from Rome and Catania more frequently used family doctors and pharmacists as a source of recommendation. Some significant difference among cities, sex and age groups were observed when the most frequently used botanicals were ranked.
Conclusions
The results provide new insights on the socio-economic characteristics and lifestyle of Italian PFS consumers, on their reasons for and pattern of use, and on their behaviour and expectations. The value of this information is not restricted to the specific country (Italy) but allows for a more general evaluation of the pattern of use, according to habits and geographical area
Dispersal: a matter of scale
Population density around the natal site is often invoked as an explanation for variation in dispersal distance, with the expectation that competition for limiting resources, coupled with increased intra‐specific aggression at high densities, should drive changes in dispersal distances. However, tests of the density‐dependent dispersal hypothesis in long‐lived vertebrates have yielded mixed results. Furthermore, conclusions from dispersal studies may depend on the spatial and temporal scales at which density and dispersal patterns are examined, yet multi‐scale studies of dispersal are rare. Here, we present the findings of a long‐term study examining factors influencing natal dispersal distances for the non‐migratory population of Peregrine Falcons (Falco peregrinus) in the British Isles across distinct spatial and temporal scales. Our smallest scale study included Peregrines ringed as nestlings and subsequently recaptured alive in south Scotland–north England, an area that was intensively studied during the time periods 1974–1982 and 2002–2016. Second, we examined dispersal patterns of birds ringed as nestlings in south Scotland–north England, but subsequently recaptured alive or recovered dead anywhere in the British Isles. Finally, we examined the natal dispersal patterns for Peregrines ringed and recaptured or recovered anywhere in the British Isles from 1964 to 2016. Consistent with prior findings, females dispersed farther than males across all scales. However, the patterns of dispersal were strongly scale dependent. Specifically, we found a lack of a discernible relationship between index of density and dispersal distance in the limited study area, but when region‐wide recaptures and recoveries were included in the analyses, a negative relationship was revealed. Our results suggest that conclusions of dispersal studies may be scale dependent, highlighting the importance of spatial and temporal scales in examining and interpreting the relationship between population density and dispersal patterns
Not all shellfish "allergy" is allergy!
The popularity of shellfish has been increasing worldwide, with a consequent increase in adverse reactions that can be allergic or toxic. The approximate prevalence of shellfish allergy is estimated at 0.5-2.5% of the general population, depending on degree of consumption by age and geographic regions. The manifestations of shellfish allergy vary widely, but it tends to be more severe than most other food allergens
The Mediterranean diet for Polish infants: a losing struggle or a battle still worth fighting?
The Mediterranean diet is well known for its health-promoting effects. Among its key ingredients, olive oil is the most characteristic. Processing industries have been successfully manufacturing and marketing jarred baby foods with the use of vegetable oils, including olive oil, as well as other sources of visible fat. We aimed to survey manufacturer claims concerning added fat in jarred infant foods supplied to the Polish market. A total of 124 kinds of infant foods from six suppliers were analyzed. Corn, canola, and soybean oil occupied the first three positions, respectively, in rank order of vegetable oils used in jarred baby foods. In our sample, only one type of ready-to-eat jars with vegetables contained olive oil. 11% of products contained cow milk butter or cream. 61% of jarred “dinners” contained poultry or fish, which are typical sources of animal protein in the Mediterranean diet. Given that commercial baby foods currently available in the Polish market contain no olive oil, we advocate considering home preparation of infant foods with the use of visible fat. Medical professionals should encourage food manufacturers to return to the concepts of the Mediterranean diet for young consumers, aimed at long-term health
High throughput screening for discovery of materials that control stem cell fate
Insights into the complex stem cell niche have identified the cell–material interface to be a potent regulator of stem cell fate via material properties such as chemistry, topography and stiffness. In light of this, materials scientists have the opportunity to develop bioactive materials for stem cell culture that elicit specific cellular responses. To accelerate materials discovery, high throughput screening platforms have been designed which can rapidly evaluate combinatorial material libraries in two and three-dimensional environments. In this review, we present screening platforms for the discovery of material properties that influence stem cell behavior
Kinetic, Isotherm and Thermodynamic Analysis on Adsorption of Cr(VI) Ions from Aqueous Solutions by Synthesis and Characterization of Magnetic-Poly(divinylbenzene-vinylimidazole) Microbeads
The magnetic-poly(divinylbenzene-1-vinylimidazole) [m-poly(DVB-VIM)] microbeads (average diameter 53–212 μm) were synthesized and characterized; their use as adsorbent in removal of Cr(VI) ions from aqueous solutions was investigated. The m-poly(DVB-VIM) microbeads were prepared by copolymerizing of divinylbenzene (DVB) with 1-vinylimidazole (VIM). The m-poly(DVB-VIM) microbeads were characterized by N2 adsorption/desorption isotherms, ESR, elemental analysis, scanning electron microscope (SEM) and swelling studies. At fixed solid/solution ratio the various factors affecting adsorption of Cr(VI) ions from aqueous solutions such as pH, initial concentration, contact time and temperature were analyzed. Langmuir, Freundlich and Dubinin–Radushkvich isotherms were used as the model adsorption equilibrium data. Langmuir isotherm model was the most adequate. The pseudo-first-order, pseudo-second-order, Ritch-second-order and intraparticle diffusion models were used to describe the adsorption kinetics. The apparent activation energy was found to be 5.024 kJ mol−1, which is characteristic of a chemically controlled reaction. The experimental data fitted to pseudo-second-order kinetic. The study of temperature effect was quantified by calculating various thermodynamic parameters such as Gibbs free energy, enthalpy and entropy changes. The thermodynamic parameters obtained indicated the endothermic nature of adsorption of Cr(VI) ions. Morever, after the use in adsorption, the m-poly(DVB-VIM) microbeads with paramagnetic property were separeted via the applied magnetic force. The magnetic beads could be desorbed up to about 97% by treating with 1.0 M NaOH. These features make the m-poly(DVB-VIM) microbeads a potential candidate for support of Cr(VI) ions removal under magnetic field
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