Association Between the Seed Storage Proteins 2S Albumin and 11S Globulin and Severe Allergic Reaction After Flaxseed Intake.

BACKGROUND: Given the increased popularity of flaxseed in meals, several cases of allergy to these seeds have been reported. Little is known about the allergens implicated in hypersensitivity reactions to flaxseed. The present study aimed to identify the allergens involved in IgE-mediated reactions in 5 patients with a clinical history of severe systemic symptoms after flaxseed consumption. METHODS: Proteins that were potential allergens with IgE-binding capacity were purified from flaxseed extract using chromatography and identified via MALDI-TOF mass spectrometry. Immunoassays were performed using the 5 allergic patients' sera tested individually and as a pool. RESULTS: Immunoblotting of the flaxseed extract revealed a low-molecular-mass protein (around 13 kDa) in 4 of the 5 patients, while a protein of approximately 55 kDa was detected in 2 patients. The proteins were identified by mass spectrometry as flaxseed 2S albumin, which is included in the WHO/IUIS allergen nomenclature as Lin u 1, and 11S globulin. Inhibition assays revealed in vitro IgE-mediated cross-reactivity between Lin u 1 and peanut and cashew nut proteins, while IgE-mediated recognition of 11S globulin by patients' sera was partially inhibited by several plant-derived sources. CONCLUSIONS: Seed storage proteins from flaxseed were involved in the development of severe symptoms in the 5 patients studied and exhibited cross-reactivity with other allergenic sources. Besides the severity of flaxseed allergy in patients sensitized to 2S albumin, this is the first time that 11S globulin has been identified as a potential allergen. Taking these data into account should ensure a more accurate diagnosis.

Fuels, power and chemical periodicity.

The insatiable-and ever-growing-demand of both the developed and the developing countries for power continues to be met largely by the carbonaceous fuels comprising coal, and the hydrocarbons natural gas and liquid petroleum. We review the properties of the chemical elements, overlaid with trends in the periodic table, which can help explain the historical-and present-dominance of hydrocarbons as fuels for power generation. However, the continued use of hydrocarbons as fuel/power sources to meet our economic and social needs is now recognized as a major driver of dangerous global environmental changes, including climate change, acid deposition, urban smog and the release of many toxic materials. This has resulted in an unprecedented interest in and focus on alternative, renewable or sustainable energy sources. A major area of interest to emerge is in hydrogen energy as a sustainable vector for our future energy needs. In that vision, the issue of hydrogen storage is now a key challenge in support of hydrogen-fuelled transportation using fuel cells. The chemistry of hydrogen is itself beautifully diverse through a variety of different types of chemical interactions and bonds forming compounds with most other elements in the periodic table. In terms of their hydrogen storage and production properties, we outline various relationships among hydride compounds and materials of the chemical elements to provide some qualitative and quantitative insights. These encompass thermodynamic and polarizing strength properties to provide such background information. We provide an overview of the fundamental nature of hydrides particularly in relation to the key operating parameters of hydrogen gravimetric storage density and the desorption/operating temperature at which the requisite amount of hydrogen is released for use in the fuel cell. While we await the global transition to a completely renewable and sustainable future, it is also necessary to seek CO2 mitigation technologies applied to the use of fossil fuels. We review recent advances in the strategy of using hydrocarbon fossil fuels themselves as compounds for the high capacity storage and production of hydrogen without any CO2 emissions. Based on these advances, the world may end up with a hydrogen economy completely different from the one it had expected to develop; remarkably, with 'Green hydrogen' being derived directly from the hydrogen-stripping of fossil fuels. This article is part of the theme issue 'Mendeleev and the periodic table'.

Elucidating in vitro and in vivo phenotypic behaviour of L. infantum/L. major natural hybrids.

The clinical manifestation and course of Leishmania infections depend on factors such as species, virulence and host-immunity. Although trypanosomatids are considered to have clonal propagation, genetic hybridization has produced successful natural hybrid lineages. Hybrids displaying strong selective advantages may have an impact on pathogenesis and the eco-epidemiology of leishmaniasis. Thus, characterization of phenotypic properties of Leishmania hybrids could bring significant insight into the biology, infectivity, pathogenicity and transmission dynamics of these atypical strains. The present study focuses on phenotypic features and survival capacity of Leishmania infantum/Leishmania major hybrid isolates as compared with representative putative parental species, L. infantum and L. major. In vitro assays (growth kinetics, susceptibility to different conditions) and in vivo infection (parasite detection and histopathological alterations) showed that hybrids present higher growth capacity and decreased susceptibility to reactive oxygen species. Furthermore, evaluation of infected spleen tissue suggests that hybrids induce a stronger immune reaction than their putative parents, leading to the development of white pulp hyperplasia in B-lymphocyte compartments. Overall, these hybrids have shown high plasticity in terms of their general behaviour within the different phenotypic parameters, suggesting that they might have acquired genetic features conferring different mechanisms to evade host cells.

Lactoferrin increases sperm membrane functionality of frozen equine semen.

During cryopreservation, sperm was submitted to an increase in reactive oxygen species generation. This work aimed to improve the quality of frozen equine sperm after the addition of antioxidants lactoferrin (Lf) and catalase (Cat) to a freezing extender. Semen from six stallions was frozen with the extenders: F1) control, INRA 82 freezing extender, F2) F1 + 500 µg/ml Lf and F3) F1 + 200 IU/ml Cat. After thawing, sperm motility parameters, membrane functionality and integrity, and acrosome integrity and spontaneous acrosome-reacted sperm were evaluated with a computer-assisted sperm analysis, a hypoosmotic swelling test and epifluorescent microscopy, respectively. Nitrite, hydroperoxide and iron concentrations of frozen semen were measured with spectrophotometry. The percentage of functional membrane sperm treated with Lf was higher (50.7% ± 11.6%) compared to that of the control (37.6% ± 15.6%), while the iron (61.4 ± 11.6 vs 73.3 ± 13.8 mg/dl) and nitrite concentrations (16.3 ± 7.1 vs 25.9 ± 4.2 µM/µg protein) were lower, respectively (p < .05). Thus, it can be suggested that Lf protect stallion spermatozoon during freezing as it has increased the percentage of sperm with functional membrane and decreased the lipid oxidant agents.

Catalytic effects of silver plasmonic nanoparticles on the redox reaction leading to ABTS˙+ formation studied using UV-visible and Raman spectroscopy.

ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) is a compound extensively employed to evaluate the free radical trapping capacity of antioxidant agents and complex mixtures such as biological fluids or foods. This evaluation is usually performed by using a colourimetric experiment, where preformed ABTS radical cation (ABTS˙+) molecules are reduced in the presence of an antioxidant causing an intensity decrease of the specific ABTS˙+ UV-visible absorption bands. In this work we report a strong effect of silver plasmonic nanoparticles (Ag NPs) on ABTS leading to the formation of ABTS˙+. The reaction of ABTS with Ag NPs has been found to be dependent on the interfacial and plasmonic properties of NPs. Specifically, this reaction is pronounced in the presence of spherical nanoparticles prepared by the reduction of silver nitrate with hydroxylamine (AgH) and in the case of star-shaped silver nanoparticles (AgNS). On the other hand, spherical nanoparticles prepared by the reduction of silver nitrate with citrate apparently do not react with ABTS. Additionally, the formation of ABTS˙+ is investigated by surface-enhanced Raman scattering (SERS) and the assignment of the most intense vibrational bands of this compound is performed. The SERS technique enables us to detect this radical cation at very low concentrations of ABTS (∼2 µM). Altogether, these findings allow us to suggest the use of ABTS/Ag NPs-systems as reliable and easy going substrates to test the antioxidant capacity of various compounds, even at concentrations much lower than those usually used in the spectrophotometric assays. Moreover, we have suggested that ABTS could be employed as a suitable agent to investigate the interfacial and plasmonic properties of the metal nanoparticles and, thus, to characterize the nanoparticle metal systems employed for various purposes.

Milk, caseinate and lactoferrin addition to equine semen cooling extenders.

Cooled semen has been used routinely to prolong sperm viability until artificial insemination time. However, spermatozoa are subjected to oxidative stress. The aim of the present work was to investigate the protective and antioxidant effect of the milk proteins lactoferrin (Lf) and caseinate added to equine semen cooling extenders. Semen from six stallions was cooled at 5 °C after resuspension with C1) milk- and glucose-based, C2) 0.6% caseinate, C3) C2 + Lf 200 µg ml-1 , C4) C2 + Lf 500 µg ml-1 and C5) C2 + Lf 1000 µg ml-1 extenders, and kept at 5 °C for 24 h. Sperm motility characteristics and intact membrane rates were not different among the treatments (P > 0.05). As a result of the cooling process, the nitrite concentration increased significantly in the cooled semen (69.6 ± 78.9 µm per ×106 spermatozoa) compared with the fresh semen (8.6 ± 1.9 µm per ×106 spermatozoa). In contrast, the H2 O2 concentrations were lower in the 0.6% caseinate extender (265.9 ± 221.3 µm per ×106 spermatozoa) than in the milk extender (430.9 ± 199.8 µm per ×106 spermatozoa, P < 0.05), showing an antioxidative effect of the caseinate compared with the milk. However, in all groups, hydrogen peroxide concentrations were similar to the undiluted fresh semen (332.8 ± 151.3 µm per ×106 spermatozoa). Caseinate showed to be as efficient as milk to protect equine-cooled spermatozoon.

Predictors of health-related quality of life of European food-allergic patients.

BACKGROUND: Although food allergy has universally been found to impair HRQL, studies have found significant differences in HRQL between countries, even when corrected for differences in perceived disease severity. However, little is known about factors other than disease severity which may contribute to HRQL in food-allergic patients. Therefore, the aim of this study was to identify factors which may predict HRQL of food-allergic patients and also to investigate the specific impact of having experienced anaphylaxis and being prescribed an EAI on HRQL. METHODS: A total of 648 European food-allergic patients (404 adults, 244 children) completed an age-specific questionnaire package including descriptive questions. Multivariable regression analyses were performed to develop models for predicting HRQL of these patients. RESULTS: For adults, the prediction model accounted for 62% of the variance in HRQL and included perceived disease severity, type of symptoms, having a fish or milk allergy, and gender. For children, the prediction model accounted for 28% of the variance in HRQL and included perceived disease severity, having a peanut or soy allergy, and country of origin. For both adults and children, neither experiencing anaphylaxis nor being prescribed an epinephrine auto-injector (EAI) contributed to impairment of HRQL. CONCLUSIONS: In this study, food allergy-related HRQL may be predicted to a greater extent in adults than in children. Allergy to certain foods may cause greater HRQL impairment than others. Country of origin may affect HRQL, at least in children. Experiencing anaphylaxis or being prescribed an EAI has no impact on HRQL in either adults or children.

The EuroPrevall outpatient clinic study on food allergy: background and methodology.

BACKGROUND: The EuroPrevall project aimed to develop effective management strategies in food allergy through a suite of interconnected studies and a multidisciplinary integrated approach. To address some of the gaps in food allergy diagnosis, allergen risk management and socio-economic impact and to complement the EuroPrevall population-based surveys, a cross-sectional study in 12 outpatient clinics across Europe was conducted. We describe the study protocol. METHODS: Patients referred for immediate food adverse reactions underwent a consistent and standardized allergy work-up that comprised collection of medical history; assessment of sensitization to 24 foods, 14 inhalant allergens and 55 allergenic molecules; and confirmation of clinical reactivity and food thresholds by standardized double-blind placebo-controlled food challenges (DBPCFCs) to milk, egg, fish, shrimp, peanut, hazelnut, celeriac, apple and peach. RESULTS: A standardized methodology for a comprehensive evaluation of food allergy was developed and implemented in 12 outpatient clinics across Europe. A total of 2121 patients (22.6% <14 years) reporting 8257 reactions to foods were studied, and 516 DBPCFCs were performed. CONCLUSIONS: This is the largest multicentre European case series in food allergy, in which subjects underwent a comprehensive, uniform and standardized evaluation including DBPCFC, by a methodology which is made available for further studies in food allergy. The analysis of this population will provide information on the different phenotypes of food allergy across Europe, will allow to validate novel in vitro diagnostic tests, to establish threshold values for major allergenic foods and to analyse the socio-economic impact of food allergy.

Catalytic dehydrogenation of propane by carbon dioxide: a medium-temperature thermochemical process for carbon dioxide utilisation.

The dehydrogenation of C3H8 in the presence of CO2 is an attractive catalytic route for C3H6 production. In studying the various possibilities to utilise CO2 to convert hydrocarbons using the sustainable energy source of solar thermal energy, thermodynamic calculations were carried out for the dehydrogenation of C3H8 using CO2for the process operating in the temperature range of 300-500 °C. Importantly, the results highlight the enhanced potential of C3H8 as compared to its lighter and heavier homologues (C2H6 and C4H10, respectively). To be utilised in this CO2 utilisation reaction the Gibbs free energy (ΔrGθm) of each reaction in the modelled, complete reacting system of the dehydrogenation of C3H8 in the presence of CO2 also indicate that further cracking of C3H6 will affect the ultimate yield and selectivity of the final products. In a parallel experimental study, catalytic tests of the dehydrogenation of C3H8 in the presence of CO2 over 5 wt%-Cr2O3/ZrO2 catalysts operating at 500 °C, atmospheric pressure, and for various C3H8 partial pressures and various overall GHSV (Gas Hourly Space Velocity) values. The results showed that an increase in the C3H8 partial pressure produced an inhibition of C3H8 conversion but, importantly, a promising enhancement of C3H6 selectivity. This phenomenon can be attributed to competitive adsorption on the catalyst between the generated C3H6 and inactivated C3H8, which inhibits any further cracking effect on C3H6 to produce by-products. As a comparison, the increase of the overall GHSV can also decrease the C3H8 conversion to a similar extent, but the further cracking of C3H6 cannot be limited.

Effect of pH on the chemical modification of quercetin and structurally related flavonoids characterized by optical (UV-visible and Raman) spectroscopy.

In this work we report the study of the chemical modifications undergone by flavonoids, especially by quercetin (QUC), under alkaline conditions by UV-visible absorption, Raman and surface-enhanced Raman scattering (SERS) spectroscopy, the study was performed in aqueous solution and also on Ag nanoparticles (AgNPs). Several processes are involved in the effect of alkaline pH both in solution and on AgNPs: autoxidation affecting mainly the C-ring of the molecule and giving rise to the molecular fragmentation leading to simpler molecular products, and/or the dimerization and further polymerization leading to species with a higher molecular weight. In addition, there exists a clear structure-instability correlation concerning mainly particular groups in the molecule: the C3-OH group in the C-ring, the catechol moiety in the B-ring and the C2=C3 bond also existing in the C-ring. QUC possesses all these groups and exhibits high instability in alkaline solution. The SERS spectra registered at different pH revealed a change in the dimerization protocol of QUC going from the A- and C-rings-like-condensation to B-ring-like-condensation. Increasing the knowledge of the chemical properties of these compounds and determining the structure-activity relationship under specific environmental factors allow us to improve their beneficial properties for health as well as the preservation of Cultural Heritage objects, for example, by preventing their degradation.

Adsorption of linear aliphatic α,ω-dithiols on plasmonic metal nanoparticles: a structural study based on surface-enhanced Raman spectra.

The adsorption mechanism of linear aliphatic α,ω-dithiols with chain lengths of 6, 8 and 10 carbon atoms on silver and gold nanoparticles has been studied by surface-enhanced Raman scattering (SERS) spectroscopy. SERS spectra provided the structural marker bands of these compounds and they were employed to obtain information about the adsorption and coordination mechanism, the orientation, conformational order, and packing of the aliphatic chains of dithiols on the metal nanoparticle surface. The effect of the type of metal (silver or gold) and the extent of surface coverage on all the above mentioned properties is discussed. It was found that the adsorption of dithiols on Au nanoparticles leads to a more disordered structure of the aliphatic chains of dithiols in comparison with the adsorption on Ag nanoparticles. The interaction through both thiol groups makes the adsorption of dithiols on metal surfaces substantially different from that of monothiols; in particular, the orientation of dithiols is perpendicular, while monothiols adopt a tilted orientation. Dithiols may act as linkers between metal nanoparticles and induce the formation of nanogaps with a controllable interparticle distance. The nanogaps thus formed are able to produce hot spots exhibiting a large intensification of electromagnetic field in these points which has been proved by the observation of intense SERS spectra of dithiols until a concentration of 10(-8) M, corresponding to a large Raman enhancement factor of 5 × 10(6).

The impact of double-blind placebo- controlled food challenge (DBPCFC) on the socioeconomic cost of food allergy in Europe.

BACKGROUND: Double-blind placebo controlled food challenge (DBPCFC) is the gold standard diagnostic test in food allergy because it minimizes diagnostic bias. OBJECTIVE: To investigate the potential effect of diagnosis on the socioeconomic costs of food allergy. METHODS: A prospective longitudinal cost analysis study was conducted in Spain and Poland within the EuroPrevall project. Food-allergic patients were enrolled into the study and in all cases diagnosis was confirmed through a standardized DBPCFC. Data were collected through a self-administered survey on all aspects of health and social care resource use, costs of living, and costs of leisure activities. Costs were measured before and 6 months after the DBPCFC and reported in international dollars with 2007 as the benchmark year. RESULTS: Forty-two patients were enrolled. Twenty-one patients had a negative DBPCFC and the suspected food was reintroduced into their diet. Comparing total direct costs before and after the DBPCFC, the reactive group spent a significantly higher amount (median increase of $813.1 over baseline), while the tolerant group's spending decreased by a median of $87.3 (P = .031). The amount of money spent on food 6 months after diagnosis was also significantly higher in the reactive group (P = .040). Finally, a larger, but not statistically significant, decrease in total indirect costs was observed in the tolerant group compared with the reactive group ($538.3 vs $32.3). CONCLUSION: DBPCFC has an impact on indirect and direct costs of living. The main contribution to this increase was money spent on food.

Influence of histological degree of seminiferous tubular degeneration and stage of seminiferous cycle on the proliferation of spermatogonia in aged Syrian hamster (Mesocricetus auratus).

The ageing testis is associated with germ loss in the seminiferous epithelium and a decrease in spermatogonia proliferation. In this work, we study whether the stages of the seminiferous epithelium cycle and/or the degree of histological tubular degeneration resulting from ageing is related with this decrease in spermatogonia proliferation. Eleven hamsters were used, five aged 6 months and six aged 24 months. In both groups, the proliferative activity was studied by BrdU immunostaining. The number of BrdU-positive and BrdU-negative cells was measured, providing the overall proliferation index in adult and aged testes. The mean number of BrdU-positive cells was also determined for each degree of histological degeneration of seminiferous epithelium, and a spermatogonia proliferation index was obtained for each stage of the seminiferous cycle. Ageing caused an overall decrease in the BrdU-positive cell percentage and a decrease in the number of BrdU-positive cells in the tubular sections with hypospermatogenesis, the sloughing of germ cells and maturation arrest, these changes being similar in both young and old animals. The spermatogonia proliferation index was only seen to be significantly lower in ageing hamster in stages VII-VIII of the seminiferous epithelium cycle. In conclusion, the overall decrease in proliferation observed in aged seminiferous epithelium is correlated with an increase in the number of degenerated sections of the seminiferous tubules, and this decrease is a phenomenon which occurs in specific stages of the seminiferous cycle.

The dynamic transcriptomic response of the goldfish brain under chronic hypoxia.

Oxygen is essential to fuel aerobic metabolism. Some species evolved mechanisms to tolerate periods of severe hypoxia and even anoxia in their environment. Among them, goldfish (Carassius auratus) are unique, in that they do not enter a comatose state under severely hypoxic conditions. There is thus significant interest in the field of comparative physiology to uncover the mechanistic basis underlying hypoxia tolerance in goldfish, with a particular focus on the brain. Taking advantage of the recently published and annotated goldfish genome, we profile the transcriptomic response of the goldfish brain under normoxic (21 kPa oxygen saturation) and, following gradual reduction, constant hypoxic conditions after 1 and 4 weeks (2.1 kPa oxygen saturation). In addition to analyzing differentially expressed protein-coding genes and enriched pathways, we also profile differentially expressed microRNAs (miRs). Using in silico approaches, we identify possible miR-mRNA relationships. Differentially expressed transcripts compared to normoxia were either common to both timepoints of hypoxia exposure (n = 174 mRNAs; n = 6 miRs), or exclusive to 1-week (n = 441 mRNAs; n = 23 miRs) or 4-week hypoxia exposure (n = 491 mRNAs; n = 34 miRs). Under chronic hypoxia, an increasing number of transcripts, including those of paralogous genes, was downregulated over time, suggesting a decrease in transcription. GO-terms related to the vascular system, oxidative stress, stress signalling, oxidoreductase activity, nucleotide- and intermediary metabolism, and mRNA posttranscriptional regulation were found to be enriched under chronic hypoxia. Known 'hypoxamiRs', such as miR-210-3p/5p, and miRs such as miR-29b-3p likely contribute to posttranscriptional regulation of these pathways under chronic hypoxia in the goldfish brain.

Clinical-Hematological Changes and Predictors of Severity in Acute Food Protein-Induced Enterocolitis Syndrome Reactions at Oral Food Challenge: A Multicenter Observational Study.

BACKGROUND: Oral food challenge (OFC) is the criterion standard for diagnosis of acute food protein-induced enterocolitis syndrome (FPIES). No diagnostic/prognostic biomarkers are available, and OFC assessment criteria are not validated. OBJECTIVE: To assess clinical-hematological changes and predictors of severity of FPIES reactions at OFC. METHODS: This was an observational multicenter prospective study. Children aged 0 to 18 years diagnosed with acute FPIES were recruited at follow-up OFC in 12 tertiary centers in Spain and Italy. OFC outcomes (as positive/negative/inconclusive and mild/moderate/severe) were assessed on the basis of published "2017 FPIES Consensus" criteria. Clinical characteristics were recorded, and full blood cell count was done at baseline, reaction onset, and 4 hours later. Regression analysis was performed to assess predictors of severe reactions at OFC. RESULTS: A total of 81 children had positive OFC (mild in 11% [9 of 81], moderate in 61% [49 of 81], and severe in 28% [23 of 81]). Increase in neutrophils and reduction in eosinophils, basophils, and lymphocytes were observed (P < .05). OFC was inconclusive in 19 cases despite objective signs or neutrophilia. Regression analysis showed that a 2-day OFC protocol where only 25% of an age-appropriate portion is given on day 1 (not sex, age, culprit food, cumulative dose, and previous reaction severity) was associated with reduced odds of severe reaction compared with giving multiple doses in a single day. CONCLUSIONS: Distinct hematological changes may help support FPIES diagnosis. Current OFC assessment criteria may not capture the broad spectrum of acute FPIES presentations. This 2-day protocol may be associated with a reduced risk of severe reactions. Future work should aim to develop safer OFC and non-OFC diagnostics for FPIES.

[History of the split between medicine and surgery]. / Dos mil años de separación entre medicina y cirugía: bases para comprender el fenómeno.

This paper summarizes historical and philosophical aspects, from Ancient Greece to the Middle Ages, concerning the split between physicians and surgeons that began to take place in Alexandria. When exploring the changes in classical medical thought and its influence on philosophy, we conclude that this historical moment was marked by a dual distinction between an essential being and a body subjected to becoming. From a unified mind in Hippocrates, in which medicine is based in knowledge of the relations, subjected to laws, of the organism exposed to natural forces Φνσις (physis among the Jonics), a rift amongst body and soul is conceived, specifically in Platonic thought, from which the surgical intervention of the body is considered improper of the medical art.

Self-perception of primary health-care staff about physical activity on prescription: A qualitative semi-structured interview.

OBJECTIVE: This study aimed to analyze the self-perception at primary health-care (PHC) nurses and general practitioners (GPs) toward PAP implementation in PHC centers. MATERIAL AND METHODS: Two semi-structured group interviews were performed separately, with five GPs and nurses working in the PHC system in the region of Madrid (Spain). An expert psychologist guided each semi-structured session. The interviews were transcribed verbatim and consensually analyzed using a content analysis. RESULTS: Half of the PHC staff considered themselves physically active and were convinced that physically active staff behavior could facilitate PAP with patients. Both GPs and nurses showed a lack of knowledge of exercise prescription but were interested in PAP and motivational training courses, as well as leadership or to collaborate under a multidisciplinary or interdisciplinary PAP approach. Some of the most relevant self-perceived PAP barriers were a confident method to measure sedentary and physical activity levels. Besides lack of staff awareness, time of consultation, and improving local community relationships and PAP policies strategies. CONCLUSIONS: There are some common self-perceptions, barriers, and facilitators among PHC nurses and GPs for PAP implementation. Following a socio-ecologic approach, this organizational data provides further insight to design a future cost-effective policy strategy to improve patient health and health-care system sustainability.