Search

In the context of climate change, it is crucial to understand whether animals that have been domesticated and (or) selected maintain their abilities to adapt to changes in their thermal environment. Here, we tested how selection for absence of early sexual maturation combined with better growth performance may have impacted thermal resistance and gene expression response in the presence of thermal stress in brook charr Salvelinus fontinalis (Mitchill, 1814). We performed temperature challenge tests on brook charr 0+ juveniles and studied the expression of genes involved in the response to oxidative stress, in synthesis of heat shock proteins, or involved in regulation of apoptosis, in heart and liver tissues. Juveniles from the selected lineage had a higher thermal resistance than controls and a loss of equilibrium occurred on average 1 °C above what was observed for the controls. The relative expressions of catalase and HSP70 were significantly higher in juveniles from the selection program. Overall, thermally sensitive fish were characterized by low mass and length and lower relative expressions of genes associated with stress response. Our results indicate that selection for traits of interests may be indirectly related to the significant lineage effect on growth in early stages of development. [ABSTRACT FROM AUTHOR]

Feline calicivirus (FCV) causes upper respiratory tract diseases and even death in cats, thereby acting as a great threat to feline animals. Currently, FCV prevention is mainly achieved through vaccination, but the effectiveness of vaccination is limited. In this study, 105 FCV strain VP1 sequences with clear backgrounds were downloaded from the NCBI and subjected to a maximum likelihood method for systematic evolutionary analysis. Based on the genetic analysis results, FCV-positive sera were prepared using SPF mice and Chinese field cats as target animals, followed by a cross-neutralization assay conducted on the different genotype strains and in vivo challenge tests were carried out to further verify with the strain with best cross-protection effect. The results revealed that FCV was mainly divided into two genotypes: GI and GII. The GI genotype strains are prevalent worldwide, but all GII genotype strains were isolated from Asia, indicating a clear geographical feature. This may form resistance to FCV prevention in Asia. The in vitro neutralization assay conducted using murine serum demonstrated that the cross-protection effect varied among strains. A strain with broad-spectrum neutralization properties, DL39, was screened. This strain could produce neutralizing titers (10  ×  23.08–10  ×  20.25) against all strains used in this study. The antibody titers against the GI strains were 10  ×  23.08–10  ×  20.5 and those against the GII strains were 10  ×  20.75–10  ×  20.25. Preliminary evidence suggested that the antibody titer of the DL39 strain against GI was higher than that against GII. Subsequent cross-neutralization assays with cat serum prepared with the DL39 strain and each strain simultaneously yielded results similar to those described above. In vivo challenge tests revealed that the DL39 strain-immunized cats outperformed the positive controls in all measures. The results of several trials demonstrated that strain DL39 can potentially be used as a vaccine strain. The study attempted to combine the genetic diversity and phylogenetic analysis of FCV with the discovery of potential vaccines, which is crucial for developing highly effective FCV vaccines. [ABSTRACT FROM AUTHOR]

Background: Effector cells assays provide an overall measure of responsiveness to allergen, but the lack of reliable and high‐throughput assays limits the clinical utility. We aimed to develop a high‐throughput basophil activation test based on human progenitor cell‐derived basophils (PCB) and investigate the role of PCB activation test (PCBAT) in allergic diseases. Methods: Progenitor cell‐derived basophils were differentiated from CD34+ progenitor cells and sensitized with sera from subjects sensitized to cat, peanut or atopic controls. Sensitized PCBs were stimulated with increasing concentrations of the corresponding allergens in vitro. Degranulation was assessed by measuring CD63 expression using flow cytometry. The correlations between PCBAT and clinical allergy were assessed. Results: Following passive sensitization of the mature PCBs with serum and allergen stimulation, an allergen specific dose‐dependent increase in CD63 expression was observed. Sera from subjects sensitized to cat (n = 35, of which 17 subjects had clinical reactivity quantified using inhaled allergen challenge), peanut allergic (n = 30, of which 15 subjects had clinical reactivity validated using double blind, placebo controlled food challenges [DBPCFC]), peanut‐sensitized but tolerant subjects (n = 5) were used to sensitize PCBs. PCBAT area under the curve (AUC) correlated with sIgE (r2 =.49, p =.001) in subjects sensitized to cat (sIgE ≥ 0.35KU/L). The provocation concentration of inhaled cat allergen (PC20) correlated with PCBAT AUC (r2 =.33, p =.016). In subjects sensitized to peanut, PCBAT AUC was highly correlated with sIgE to Ara h 2 (r2 =.59, p <.0001). Peanut threshold cumulative dose during DBPCFC was negatively correlated with PCBAT AUC (r2 =.57, p =.001) and IgE to Ara h1 (r2 =.55, p =.007), but not with sIgE to whole peanut or Ara h2. All peanut‐sensitized but tolerant subjects showed no reaction to peanut on PCBAT. Conclusion: Progenitor cell‐derived basophils activation test is a high‐throughput assay, which correlates with clinical allergy and may confer a powerful alternative tool in allergy testing. [ABSTRACT FROM AUTHOR]

Challenge tests are commonly employed to evaluate the growth behavior of L. monocytogenes in food matrices; they are known for being expensive and time-consuming. An alternative could be the use of predictive models to forecast microbial behavior under different conditions. In this study, the growth behavior of L. monocytogenes in different fresh produce was evaluated using a predictive model based on the Gamma concept considering pH, water activity (a w), and temperature as input factors. An extensive literature search resulted in a total of 105 research articles selected to collect growth/no growth behavior data of L. monocytogenes. Up to 808 L. monocytogenes behavior values and physicochemical characteristics were extracted for different fruits and vegetables. The predictive performance of the model as a tool for identifying the produce commodities supporting the growth of L. monocytogenes was proved by comparing with the experimental data collected from the literature. The model provided satisfactory predictions on the behavior of L. monocytogenes in vegetables (>80% agreement with experimental observations). For leafy greens, a 90% agreement was achieved. In contrast, the performance of the Gamma model was less satisfactory for fruits, as it tends to overestimate the potential of acid commodities to inhibit the growth of L. monocytogenes. • The Gamma concept model for L. monocytogenes growth was tested in fresh produce. • The model performance was very satisfactory for leafy greens (90% of the cases). • Less satisfactory (71.8%) was the performance of the model for fruits. • The failure predictions of the model are discussed including the impact of other factors. [ABSTRACT FROM AUTHOR]

Background: The use of eliciting doses (EDs) for food allergens is necessary to inform individual dietary advice and food allergen risk‐management. The Eliciting Dose 01 (ED01) for milk and egg, calculated from populations of allergic subjects undergoing oral food challenges (OFCs), are 0.2 mg total protein. The respective Eliciting Dose 05 (ED05) is 2.4 mg for milk and 2.3 mg for egg. As about 70% children allergic to such foods may tolerate them when baked, we sought to verify the EDs of that subpopulation of milk and egg‐allergic children. Methods: We retrospectively assessed consecutive OFC for fresh milk and egg between January 2018 and December 2020 in a population of baked food‐tolerant children. Results: Among 288 children (median age 56 ‐ IQR 36–92.5 months, 67.1% male) included, 87 (30.2%) returned positive OFC results, 38 with milk and 49 with egg. The most conservative ED01 was 0.3 mg total protein (IQR 0.03–2.9) for milk and 14.4 mg total protein (IQR 3.6–56.9) for egg. The respective ED05 was 4.2 (IQR 0.9–19.6) mg for milk and 87.7 (IQR 43–179) mg for egg. Such thresholds are, respectively, 1.5 (milk ED01), 1.75 (milk ED05), 72 (egg ED01), and 38.35 (egg ED05) times higher than the currently used thresholds. Conclusions: The subpopulation of children allergic to milk and egg, but tolerant to baked proteins, displays higher reactivity thresholds than the general population of children allergic to milk and egg. Their risk stratification, in both individual and population terms, should consider this difference. In baked milk‐tolerant children, milk causes reactions at lower doses than egg in our group of egg‐tolerant children. This could be associated with the relative harmlessness of egg compared with milk in the determinism of fatal anaphylactic reactions in children. [ABSTRACT FROM AUTHOR]

Background: Cystic fibrosis (CF) is reported to be a risk factor for drug hypersensitivity. However, there are conflicting data about true prevalence of drug hypersensitivity in children with CF. Methods: The suspicious drug hypersensitivity reactions (DHRs) of children with CF were enquired by the European Network for Drug Allergy (ENDA) questionnaire, and skin tests and/or drug provocation tests were performed according to the established guidelines. Results: Two hundred and nineteen children (48.9% boys; median [IQR] age, 8.4 years [4.8- 12.4 years]) with cystic fibrosis were included in the study, among which 22 patients with 24 suspected DHRs were evaluated. Most of the suspected DHRs were of non- immediate (n = 16, 66.6%) type, and the offending drugs were amoxicillinclavulanic acid (n = 7), macrolides (n = 4), trimethoprim- sulfamethoxazole (TMP/SMX) (n = 2), piperacillin- tazobactam (n = 1), pancrelipase (n = 1), and ursodeoxycholic acid (n = 1). Eight (33.3%) of the DHRs were classified as immediate (ceftriaxone [n = 2], ceftazidime [n = 2], meropenem [n = 1], AmBisome [n = 2], and vancomycin [n = 1]). The main clinical presentations were maculopapular eruption (41.6%) and urticaria (37.5%), accompanied by angioedema (8.3%), flushing (12.5%), and vomiting (8.3%). Nine skin tests (with beta- lactam protocol in 6 patients) and 24 DPTs were performed, and none of the skin tests revealed a positive result; however, 2 DPTs with TMP/SMX were positive. Conclusion: Actual drug hypersensitivity was demonstrated in 2 of 219 patients (0.9%) with non- beta- lactam antibiotics. These results conflict with previous researches that showed higher drug hypersensitivity rates but are consistent with some recent studies. Allergological diagnostic workup is mandatory in patients with cystic fibrosis in case of a suspicious DHR. [ABSTRACT FROM AUTHOR]

Background: To determine the proportion and reproducibility of cat‐allergic mild asthmatics with early asthmatic response (EAR) during cat allergen exposure in a naturalistic exposure chamber (NEC). Methods: This was a prospective, observational study in 30 cat‐allergic mild asthmatics who received two 180‐min cat‐allergen (Felis domesticus allergen 1 [Fel d 1]) challenges 27 days apart in an NEC. Results: An EAR (≥20% reduction from baseline in forced expiratory volume in 1 s [FEV1]) was observed in 67% and 52% of subjects at first and second NEC exposure, respectively, with similar median time to EAR; 44% of subjects had an EAR on days 1 and 28. Late asthmatic response (≥15% reduction in FEV1 within 24 h of NEC exit) was observed in 33% of subjects following either exposure. Average FEV1 and total nasal symptom score during NEC exposure were highly correlated within subjects between NEC exposures (r = 0.91, p < 0.0001; r = 0.73, p < 0.001), but total ocular symptom score was not. Time to EAR, but not average FEV1, was significantly associated with NEC Fel d 1 concentration, which was variable. There were no serious adverse events; 12/30 subjects experienced 20 adverse events (including asthma, 10%; headache, 10%). Conclusions: The NEC model demonstrates that average FEV1 change is highly reproducible and has a low correlation with cat allergen levels. However, time to EAR and incidence of EAR are less reproducible and are highly correlated with NEC allergen levels. Average FEV1, rather than incidence of EAR or time to EAR, could be considered as an endpoint for interventional trials testing cat‐specific anti‐allergy therapies using an NEC. [ABSTRACT FROM AUTHOR]

(B) Time course of neutrophils, eosinophils, NK cells, T lymphocytes and monocytes following allergen nasal challenge or diluent. Keywords: challenge tests; eosinophils; innate lymphoid cells and NK cells; lipoxin; rhinitis EN challenge tests eosinophils innate lymphoid cells and NK cells lipoxin rhinitis 309 313 5 12/31/21 20220101 NES 220101 ACKNOWLEDGMENTS We thank Pr Seiamak Bahram and Dr Beatrice Uring-Lambert for access to flow cytometer. [Extracted from the article]

Background: Peanut and tree nut allergies are the most important causes of anaphylaxis. Co‐reactivity to more than one nut is frequent, and co‐sensitization in the absence of clinical data is often obtained. Confirmatory oral food challenges (OFCs) are inconsistently performed. Objective: To investigate the utility of the basophil activation test (BAT) in diagnosing peanut and tree nut allergies. Methods: The Markers Of Nut Allergy Study (MONAS) prospectively enrolled patients aged 0.5–17 years with confirmed peanut and/or tree nut (almond, cashew, hazelnut, pistachio, walnut) allergy or sensitization from Canadian (n = 150) and Austrian (n = 50) tertiary pediatric centers. BAT using %CD63+ basophils (SSClow/CCR3pos) as outcome was performed with whole blood samples stimulated with allergen extracts of each nut (0.001‐1000 ng/mL protein). BAT results were assessed against confirmed allergic status in a blinded fashion to develop a generalizable statistical model for comparison to extract and marker allergen‐specific IgE. Results: A mixed effect model integrating BAT results for 10 and 100 ng/mL of peanut and individual tree nut extracts was optimal. The area under the ROC curve (AUROC) was 0.98 for peanut, 0.97 for cashew, 0.92 for hazelnut, 0.95 for pistachio, and 0.97 for walnut. The BAT outperformed sIgE testing for peanut or hazelnut and was comparable for walnut (AUROC 0.95, 0.94, 0.92) in a sub‐analysis in sensitized patients undergoing OFC. Conclusions: Basophil activation test can predict allergic clinical status to peanut and tree nuts in multi‐nut‐sensitized children and may reduce the need for high‐risk OFCs in patients. [ABSTRACT FROM AUTHOR]

Diagnosis of food allergy is often very difficult. Patients report numerous symptoms that are sometimes difficult to associate with a specific kind of food. Despite the development of immunological diagnostic methods, most importantly the increasing availability of component resolved diagnosis, in vivo tests, in particular oral challenge tests, are necessary to reliably assess the actual course of the patient's symptoms. Food challenges are time-consuming and often difficult to prepare. For this reason, other alternative diagnostic methods are being sought, such as various skin prick test modifications. These methods raise numerous controversies and doubts in clinicians. In particular many concerns are gathered with the diagnosis of IgE-independent reactions. Atopy patch tests raised hopes in this area, but it turned out that their specificity is limited and the interpretation of the result difficult. In this article we present practical aspects of conducting in vivo diagnosis in patients suspected of food allergies. Based on literature data and own observations, we explaine what are the limitations of in vivo diagnostic tests and how the patient's diagnostic procedure can be improved. [ABSTRACT FROM AUTHOR]

While the measured allergen levels are much less variable than those in homes or studies using blanket shaking, some variability was observed, as was expected due to natural variation in the cats' allergen production, changes in human and cat activity, and the effects of cleaning. Keywords: aerobiology; animal models; asthma; challenge tests; clinical immunology EN aerobiology animal models asthma challenge tests clinical immunology 685 687 3 02/01/22 20220201 NES 220201 ACKNOWLEDGMENTS The authors thank Karim Saadé, Zachary Huffman, Kieran Eveleigh, and Nicholas Ogrodnik for their support in testing and development. To account for the greater size of the chamber, rather than increasing the number of cats, carpet allergen levels were supplemented by shaking cat bedding several days in advance of testing, and by adding 10 or 20 g of additional milled cat hair (Stallergenes Greer) directly to the carpets. [Extracted from the article]

In recent years, pre-packed ready-to-eat (RTE) food products on the Belgian market have shifted to a more plant-based composition due to a variety of reasons, including consumer concerns about health, animal welfare, and sustainability. However, similar to animal-based RTE foods, plant-based RTE foods can be susceptible to the presence and outgrowth of Listeria monocytogenes (L. monocytogenes). Three innovative, pre-packed, plant-based RTE food product categories on the Belgian market were identified based upon data gaps regarding the prevalence and growth potential of this pathogen. These were vegetarian and vegan deli sandwich slices (category 1), fresh-cut (mixes of) leafy vegetables (category 2), and multi-ingredient salad bowls (category 3). Reports on associated listeriosis outbreaks and recalls were collected and a comprehensive literature review on the prevalence of L. monocytogenes (i.e. detection in 25 g food) was performed. In addition, the prevalence of L. monocytogenes was also determined through an exploratory retail survey of ca. 50 different RTE products of each category. A batch was considered positive if L. monocytogenes was detected in a food item, either on the day of purchase, at the end of shelf life, or both. During the retail survey, L. monocytogenes was not detected in category 2 (0 out of 51 batches), while 1 out of 51 and 6 out of 48 batches were found positive for respectively category 1 and 3. The observed L. monocytogenes concentration did not exceed 10 CFU/g at any point in time in any batch. Furthermore, challenge tests were performed to determine the growth potential of L. monocytogenes in nine pre-packed, plant-based RTE food products (two to four different products of each category, and three different batches per product). After inoculation, products were stored for half of their shelf life at 7 °C and half of their shelf life at 9 °C (simulation of resp. retail and consumer storage). In six of the nine challenge tests executed, growth of L. monocytogenes was supported (i.e. growth potential ≥0.50 log 10 CFU/g during shelf life). The highest growth potential was observed for fresh-cut iceberg lettuce (3.60 log 10 CFU/g in 9 days), but a large variation regarding the growth potential of L. monocytogenes was noted both between and within the three studied pre-packed, plant-based RTE food product categories. This variation was mainly caused by differences in product composition, physicochemical product characteristics, present (competitive) microbiota such as lactic acid bacteria, applied preservation techniques, and shelf life. • Prevalence and growth potential of L. monocytogenes in plant-based RTE deli sandwich slices, leafy vegetables and salad bowls • The overall L. monocytogenes prevalence amounted to 4.6 % (7 out of 150 batches) • The L. monocytogenes concentration did not exceed 10 CFU/g at any time in any batch. • In 6 out of 9 challenge tests, growth of L. monocytogenes was supported. • Highest growth potential for fresh-cut iceberg lettuce: 3.6 log 10 CFU/g in 9 days [ABSTRACT FROM AUTHOR]

Keywords: allergy diagnosis; atopic dermatitis; challenge tests; complementary feeding; food allergy; pediatrics; prevention; weaning EN allergy diagnosis atopic dermatitis challenge tests complementary feeding food allergy pediatrics prevention weaning 1592 1594 3 05/17/21 20210501 NES 210501 Oral tolerance induction (OTI) is the only RCT-proven effective intervention for preventing childhood food allergy.1,2 OTI to peanut is highly effective in a high-risk population with an 81% relative risk ration (RRR) to peanut allergy.3 OTI also reduced egg allergy in the general population in a per-protocol analysis.1 These published RCT findings have changed practice and many governmental and allergy societies now recommend introducing peanut in infancy; some suggest that other foods, such as well-cooked egg, are also introduced. Commencing multiple food OTI at 4 months of age has no detrimental effect on established breastfeeding.6,7 All children may adopt a diverse weaning diet,8 including allergenic foods such as well-cooked egg and peanut, as soon as weaning commences. Allergy diagnosis, atopic dermatitis, challenge tests, complementary feeding, food allergy, pediatrics, prevention, weaning. [Extracted from the article]

A mechanism-based biomarker model of TNFα-response, including different external provocations of LPS challenge and test compound intervention, was developed. The model contained system properties (such as kt, kout), challenge characteristics (such as ks, kLPS, Km, LPS, Smax, SC50) and test-compound-related parameters (Imax, IC50). The exposure to test compound was modelled by means of first-order input and Michaelis–Menten type of nonlinear elimination. Test compound potency was estimated to 20 nM with a 70% partial reduction in TNFα-response at the highest dose of 30 mg·kg−1. Future selection of drug candidates may focus the estimation on potency and efficacy by applying the selected structure consisting of TNFα system and LPS challenge characteristics. A related aim was to demonstrate how an exploratory (graphical) analysis may guide us to a tentative model structure, which enables us to better understand target biology. The analysis demonstrated how to tackle a biomarker with a baseline below the limit of detection. Repeated LPS-challenges may also reveal how the rate and extent of replenishment of TNFα pools occur. Lack of LPS exposure-time courses was solved by including a biophase model, with the underlying assumption that TNFα-response time courses, as such, contain kinetic information. A transduction type of model with non-linear stimulation of TNFα release was finally selected. Typical features of a challenge experiment were shown by means of model simulations. Experimental shortcomings of present and published designs are identified and discussed. The final model coupled to suggested guidance rules may serve as a general basis for the collection and analysis of pharmacological challenge data of future studies. [ABSTRACT FROM AUTHOR]

This study presents an approach to determine the survival of diverse foodborne pathogens (Escherichia coli, Staphylococcus aureus, Listeria monocytogenes, and Salmonella enterica) in three Aloreña de Málaga table olive commercial presentations (fresh green, traditional, and cured olives). The microbial survival in this green natural table olive speciality was fit using a log-linear regression model implemented in GInaFIT. The contents of sugars, phenolic compounds, additives, salt, pH, and levels of autochthonous microorganisms differed among presentations and affected the survival of microorganisms. The inoculated initial populations of pathogens (7–8 log10 CFU/mL brine) decreased rapidly and, 48 h after inoculation, their counts were always below the detection limit (

Keywords: asthma; bronchial provocation; challenge tests; sports EN asthma bronchial provocation challenge tests sports 1 3 3 07/29/20 20200801 NES 200801 To the Editor, Exercise-induced bronchoconstriction (EIB) is highly prevalent in children and adults with asthma, and elite athletes. Data regarding EIB diagnosis thresholds for exercise provocation testing were also obtained. As a first-line diagnostic test, 48% of respondents conducted mannitol challenges, 45% exercise provocation challenges, 3% cardiopulmonary exercise testing and 3% histamine challenge testing. [Extracted from the article]

Acetylsalicylic acid challenge optimal dose in nonsteroidal anti-inflammatory drugs hypersensitivity diagnosis Keywords: allergy diagnosis; challenge tests; drug allergy EN allergy diagnosis challenge tests drug allergy 1501 1503 3 06/01/20 20200601 NES 200601 To the Editor, Nonsteroidal anti-inflammatory drugs (NSAIDs) are among the most frequently prescribed and consumed drugs worldwide in all ages, being reported as the main cause of drug hypersensitivity reactions (DHRs). Allergy diagnosis, challenge tests, drug allergy. [Extracted from the article]

Feline calicivirus (FCV) causes upper respiratory tract diseases and even death in cats, thereby acting as a great threat to feline animals. Currently, FCV prevention is mainly achieved through vaccination, but the effectiveness of vaccination is limited. In this study, 105 FCV strain VP1 sequences with clear backgrounds were downloaded from the NCBI and subjected to a maximum likelihood method for systematic evolutionary analysis. Based on the genetic analysis results, FCV-positive sera were prepared using SPF mice and Chinese field cats as target animals, followed by a cross-neutralization assay conducted on the different genotype strains and in vivo challenge tests were carried out to further verify with the strain with best cross-protection effect. The results revealed that FCV was mainly divided into two genotypes: GI and GII. The GI genotype strains are prevalent worldwide, but all GII genotype strains were isolated from Asia, indicating a clear geographical feature. This may form resistance to FCV prevention in Asia. The in vitro neutralization assay conducted using murine serum demonstrated that the cross-protection effect varied among strains. A strain with broad-spectrum neutralization properties, DL39, was screened. This strain could produce neutralizing titers (10 × 2 3.08 -10 × 2 0.25 ) against all strains used in this study. The antibody titers against the GI strains were 10 × 2 3.08 -10 × 2 0.5 and those against the GII strains were 10 × 2 0.75 -10 × 2 0.25 . Preliminary evidence suggested that the antibody titer of the DL39 strain against GI was higher than that against GII. Subsequent cross-neutralization assays with cat serum prepared with the DL39 strain and each strain simultaneously yielded results similar to those described above. In vivo challenge tests revealed that the DL39 strain-immunized cats outperformed the positive controls in all measures. The results of several trials demonstrated that strain DL39 can potentially be used as a vaccine strain. The study attempted to combine the genetic diversity and phylogenetic analysis of FCV with the discovery of potential vaccines, which is crucial for developing highly effective FCV vaccines., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Yang, Liu, Chen, Feng, Qi, Zheng, Wang, Kang, Jiang, Yang, Qu and Liu.)

This study presents an approach to determine the survival of diverse foodborne pathogens (Escherichia coli, Staphylococcus aureus, Listeria monocytogenes , and Salmonella enterica) in three Aloreña de Málaga table olive commercial presentations (fresh green, traditional, and cured olives). The microbial survival in this green natural table olive speciality was fit using a log-linear regression model implemented in GInaFIT. The contents of sugars, phenolic compounds, additives, salt, pH, and levels of autochthonous microorganisms differed among presentations and affected the survival of microorganisms. The inoculated initial populations of pathogens (7–8 log10 CFU/mL brine) decreased rapidly and, 48 h after inoculation, their counts were always below the detection limit (<1.3 log10 CFU/mL), except for S. aureus in the fresh green presentation which was ∼ 5.0 log10 CFU/mL. The highest maximum death rates (kmax) and lowest periods for 4 log10 reductions (4Dr) were observed in cured olives but decreased and increased, respectively, from the traditional to the fresh green presentations. L. monocytogenes and S. aureus were the most resistant species. The multivariate analysis showed that high concentrations of compounds released from the olives (sugars and phenols) were positively associated to 4Dr and negatively to kmax. Conversely, the presence of preservatives reduced 4Dr. This study, executed in commercial products, pointed out that packaged table olives are adverse habitats for foodborne pathogens with their effects being presentation dependent. The survival of S. aureus was particularly long in green fresh Aloreña de Málaga table olives packaged without preservatives; therefore, its changes in this presentation still requires further in-deep research. [ABSTRACT FROM AUTHOR]

Abstract: Background: Food allergy significantly impairs health‐related quality of life (HRQL). Currently, it is still unknown whether diagnostic interventions for food allergy improve HRQL. We aim to assess the impact of diagnostic interventions for food allergy on HRQL. Methods: A systematic search was performed in MEDLINE, Embase, Cochrane Library, and CINAHL focused on patients with a (suspected) food allergy who underwent diagnostic interventions (ie, skin prick test, specific IgE, or oral food challenges [OFC]) and in whom HRQL was assessed. The mean difference between HRQL before and after the diagnostic intervention was calculated. A minimal clinically important difference of 0.5 was considered clinically relevant for the food allergy quality of life questionnaire. Results: Seven of 1465 original identified publications were included in which the impact of an OFC on HRQL was investigated (total patients n = 1370). No other diagnostic interventions were investigated. Food allergy‐specific parent‐reported HRQL improved significantly after an OFC irrespective of the outcome in children with a suspected food allergy in two publications. The change was considered clinically relevant in one of two publications. In addition, parent‐reported HRQL improved after an OFC to assess the eliciting dose in children with a confirmed food allergy. The parental burden was significantly reduced after an OFC to assess resolution of food allergy. A meta‐analysis could not be performed due to the limited numbers of, and considerable heterogeneity between, eligible publications. Conclusion: An OFC is associated with an improved food allergy‐specific HRQL and a reduced parental burden of food allergy. [ABSTRACT FROM AUTHOR]

This paper presents a discussion of principles and problems of neurotransmitter challenge tests using examples of experiments, most of which were performed in the author's laboratory. Drugs targeting synthesis, release, receptors or reuptake of dopamine, serotonin and noradrenergic transmitter (TM) systems were used for characterizing or discriminating certain temperament or personality traits and their sub-factors. Any personality or temperament trait is characterized by multiple TM responses, thus constellations of hormone responses to drugs acting on different TM systems or on different sources of TM activity were investigated within individuals in crossover designs. The major conclusions are: (i) intra-individual patterns of hormone responses to different TM-related drugs, or to agonists and antagonists, can help to discriminate subtypes of temperament dimensions, and (ii) the latency and shape of response curves may help specify processes of biological responses related to psychological dimensions and reveal common TM sensitivities in clusters of traits. TM sensitivity, defined by hormone responses, does not always correspond to accompanying behavioural indicators, but may provide more specific information on underlying mechanisms. Additional consideration of drug doses and experimental induction of stressors may serve to identify temperament-related susceptibilities to certain drugs. Limitations of the challenge approach and recommendations for future research are discussed. This article is part of the theme issue 'Diverse perspectives on diversity: multi-disciplinary approaches to taxonomies of individual differences'. [ABSTRACT FROM AUTHOR]

Abstract: Background: Cow's milk allergy (CMA) affects 2% of all children. This study investigatescomponent‐resolved diagnostics(CRD) to cow's milk proteins in children suspected of CMA, by correlating the level of CRD with outcome of the oral challenge. Furthermore, we evaluate the ability of serial CRD measurements to distinguish children with persistent CMA from children developing tolerance. Methods: We included data from 78 children referred to the Allergy Centre during a 13‐year period. Results from oral food challenges including threshold, severity, and sensitization data (IgE antibodies to whole milk protein, IgE components toward milk and skin prick test (SPT)) were collected. The milk allergic children were re‐evaluated with sensitization data and rechallenges regularly. Results: Thirty‐nine children had negative first challenges, and 39 had positive first challenges. The positive group was rechallenged and separated into 3 groups depending on time to remission. At inclusion, children with persistent CMA had significantly larger size of SPT and higher levels of s‐IgE to milk and CRD compared to the other groups. SPT wheal size was significantly larger in children with persistent CMA compared to children outgrowing CMA. Furthermore, a correlation between s‐IgE level to cow's milk and casein and the severity of the allergic reaction elicited by food challenges was found. Conclusion: Oral food challenge cannot be replaced by s‐IgE to whole milk protein or milk components nor SPT in the diagnosis of CMA; however, high levels of milk components and s‐IgE to milk increase the risk of a long‐lasting or persisting CMA. [ABSTRACT FROM AUTHOR]

Lack of drive in depression has been reported to derive from deficiency of dopamine, whereas high responsiveness of the noradrenergic and serotonergic system have been found to be associated with anxiety related components of depression. Since, furthermore, the three neurotransmitters and depression are relevant in smoking motivation, the present experiment investigates if fatigability (FA) and stress reactivity (SR), the two corresponding components of depressiveness measured as personality dimensions in the normal range, can be separated by drug induced hormone responses and cigarette craving and their combined effects. Method 36 Healthy male smokers assessed for FA and SR by questionnaires were tested under noradrenergic (NA), serotonergic (5-HT) and dopaminergic (DA) pharmacological stimulation in a placebo controlled balanced crossover design with respect to time and size of drug induced hormone responses and measures of cigarette craving during nicotine deprivation. Results Revealed that both FA and SR were related to early 5-HT responses but only FA showed late and low DA responses confirming the DA deficiency hypothesis. Smoking urge was increased by the noradrenergic drug merely in stress sensitive individuals, and larger prolactin responses to DA were associated with increased smoking urge. Conclusions Facets of depressiveness can be discriminated by neurotransmitter related hormone responses. Personality related differences in motivation may be revealed by psychotropic drugs, and their underlying mechanisms may become evident by neurochemical responses to psychotropic drugs. [ABSTRACT FROM AUTHOR]

Nitrate and nitrite salts perform a versatile role in fermented meats, including the inhibition of food pathogens (in particular proteolytic group I Clostridium botulinum). Despite the increasing interest in clean-label products, little is known about the behaviour of this pathogen in response to the removal of chemical preservatives from fermented meat formulations. Therefore, challenge tests with a cocktail of nontoxigenic group I C. botulinum strains were performed to produce nitrate/nitrite-free fermented sausages under different acidification conditions and starter culture formulations, including the use of an anticlostridial Mammaliicoccus sciuri strain. Results showed limited outgrowth of C. botulinum , even in the absence of acidification. The anticlostridial starter culture did not lead to an additional inhibitory effect. The selective plating procedure adopted within this study proofed robust to follow germination and growth of C. botulinum , inhibiting common fermentative meat microbiota. The challenge tests constitute a suitable tool to assess the behaviour of this food pathogen within fermented meats upon nitrate- and nitrite omission. • Nitrate/nitrite are added to fermented meats to inhibit Clostridium botulinum. • Challenge tests were carried out to monitor nontoxic proteolytic C. botulinum strains. • Growth of C. botulinum was very limited in fermented sausages free of nitrate/nitrite. • Use of an anticlostridial starter culture did not show an additional inhibitory effect. [ABSTRACT FROM AUTHOR]

In the EU, food is considered safe with regard to Listeria monocytogenes if its numbers do not exceed 100 CFU/g throughout the shelf-life of the food. Therefore, it is important to determine if a food supports growth of L. monocytogenes. Challenge studies to determine the ability of a food to support growth of L. monocytogenes are essential as predictive modelling often overestimates the growth ability of L. monocytogenes. The aim of this study was to determine if growth of L. monocytogenes was supported during the production and distribution of mushrooms. A three-strain mixture of L. monocytogenes was inoculated onto three independent batches of whole mushrooms, sliced mushrooms, mushroom casing and mushroom substrate at a concentration of about 100–1000 CFU/g. The batches were incubated at potential abuse temperatures, as a worst case scenario, and at intervals during storage L. monocytogenes numbers, % moisture and pH were determined. The results showed that the sliced and whole mushrooms had the ability to support growth, while mushroom casing allowed survival but did not support growth. Mushroom substrate showed a rich background microflora that grew on Listeria selective media and this hindered enumeration of L. monocytogenes. In the case of this study, Combase predictions were not always accurate, indicating that challenge studies may be a necessary part of growth determination of L. monocytogenes.

The aim of this study was to develop a predictive model for the growth of L . monocytogenes and Salmonella in the pulp and the outer rind of Canary melons ( Cucumis melo L.) as a function of temperature. The experiments of L . monocytogenes and Salmonella enterica showed that the former can grow in all temperatures tested, from 5 °C to 35 °C, both on the outer rind and in the pulp of melons while the latter did not grow when the outer rind and the pulp of Canary melons were stored at 5 °C. There was no significant difference (p > 0.05) regarding the growth kinetic parameters [growth rate (μ) and lag time (λ)] when the pathogens were inoculated on the outer rind and pulp following storage between 15 and 35 °C. Secondary models (Ratkowsky model) were able to describe the influence of temperature on μ and λ for both microorganisms on the outer rind and pulp of Canary melons. This study adds quantitative data to the literature on the fate of L . monocytogenes and S . enterica in Canary melons and reveal that pulp and the outer rind of this fruit comprise substrates that support the growth of both pathogens in a wide range of storage temperature. [ABSTRACT FROM AUTHOR]

The aim of this study is the evaluation of the specificity and sensitivity of the skin prick tests (SPTs), specific IgE and atopy patch tests (APTs) in atopic dermatitis patients suffering from food allergy. A total of 301 patients were examined, complete dermatological and allergological examination was performed in all patients. The food allergy was confirmed to peanuts in 62 patients (20%), to egg in 16 patients (5%), to soy in 9 patients (3%), to wheat in 12 patients (4%) and to cow milk in 6 patients (2%). The specificity of SPT, specific IgE and APT is considered as good; the sensitivity of APT is low. The positive results in isolation cannot confirm the food allergy; however, together with other diagnostic methods, such as clinical history and open exposure test, these tests are valuable tool in examination of food allergy. [ABSTRACT FROM AUTHOR]

Aim: The evaluation of the importance of atopy patch tests in patients suffering from food allergy to egg’s white and yolk, peanuts, soy, cow’s milk and wheat.Methods: 240 patients were examined. Complete dermatological and allergological examination was performed in all patients including specific IgE, skin prick test, atopy patch test and the challenges tests.Results: The specificity of atopy patch tests is for soy 96%, for egg 95%, for wheat 95%, for peanuts 99% and for milk 99%. The sensitivity of atopy patch tests is for soy 62%, for egg 35.7%, for wheat 16.7%, for peanuts 20.8% and for milk 50%.Conclusion: The specificity of atopy patch tests may be considered good; regarding the sensitivity, the high percentage of false negative results should make us believe that these tests are not conclusive. [ABSTRACT FROM AUTHOR]

Few studies concerning the occurrence of cow’s milk allergy with the use of double-blind, placebo controlled food challenge test in adolescents and adult patients suffering from atopic dermatitis exist. Aim: To evaluate the occurrence of cow’s milk allergy in adolescents and adults suffering from atopic dermatitis. Method: Altogether 179 persons suffering from atopic dermatitis were included in the study: 51 men and 128 women entered the study with the average age of 26.2 (s.d. 9.5 years). Complete dermatological and allergological examinations were performed. Results: The positive results in specificIgE and in skin prick tests were recorded in 12% of patients. According to the open exposure tests and double-blind, placebo controlled food challenge tests these patients are only sensitized to cow’s milk without clinical symptoms of allergy. Double-blind, placebo controlled food challenge test confirmed food allergy to cow milk only in one patient (worsening of atopic dermatitis), the oral allergy syndrome was observed in another one patient, occurrence of this allergy was altogether 1.1%. Conclusion: Cow’s milk allergy rarely plays a role in the worsening of atopic dermatitis in adolescent and adult patients.

Few studies concerning the importance of wheat allergy affecting the course of atopic eczema in adolescents and adult patients exist. Aim: The evaluation if wheat allergy can deteriorate the course of atopic eczema. Follow-up of patients with confirmed food allergy to wheat. Method: Altogether 179 persons suffering from atopic eczema were included in the study: 51 men and 128 women entered the study with an average age of 26.2 (s.d. 9.5 years) Dermatological and allergological examinations were performed, including skin prick tests, atopy patch tests, and specific serum IgE for wheat, open exposure test and double-blind, placebo-controlled food challenge test with wheat flour. Results: Wheat allergy affecting the coures of atopic eczema was confirmed in eight patients (4.5%) out of 179 patients enrolled in this study by double-blind, placebo controlled food challenge test. The course of atopic eczema showed a positive trend in patients with confirmed food allergy at 3, 6, 9, 12 month follow-up (statistical evaluation with paired t-test) after the elimination of wheat flour. Conclusion: Wheat allergy may play an important role in the worsening of atopic eczema (acting as a triggering exacerbating factor) only in a minority of adolescents and adult patients (4.5% in our study). The diagnostic methods (skin prick test, specific IgE, atopy patch test, history) cannot be used as separated tests for the determination of food allergy to wheat in patients with atopic eczema.Open exposure tests and double-blind, placebo-controlled food challenge should be used for the confirmation of wheat allergy affecting the course of atopic eczema.