A multi-center assessment to compare residual allergenicity of partial hydrolyzed whey proteins in a murine model for cow's milk allergy - Comparison to the single parameter guinea pig model.

INTRODUCTION: This 4-center study is part of a project to validate a food allergy murine model for safety testing of hydrolyzed infant formulas. AIM: The aim of the current multi-center experiment was to evaluate the residual allergenicity of three partial hydrolyzed whey proteins (pWH) in a multiple-parameter cow's milk allergy murine model and to compare to the classically used guinea pig model. Previous work showed differences in the magnitude of the allergic response to whey between centers. To get a first insight in the effect of housing on the robustness of the mouse model, microbiota composition of non-sensitized mice was analyzed and compared between centers. METHODS: Mice were sensitized intragastrically (i.g.) with whey, pWH or eWH using cholera toxin as an adjuvant. In mice, whey-IgE/IgG1, acute allergic symptoms were determined upon whey challenge. Guinea pigs were orally sensitized ad libitum via the drinking water (day 0-37) and challenged intravenously with whey on day 49. The microbial composition in fecal samples was determined in non-sensitized mice in all 4 research centers before and after conduct of the study. RESULTS: Elevated levels of whey-IgG1 were detected in whey-sensitized mice in all centers. Except for pWH-A in center 4, we observed elevated levels of whey-IgE in whey-sensitized mice and mice sensitized with pWH-A, -B, -C. Center 2 was excluded from further analysis because of non-significant IgE levels in the positive control. In contrast to whey-mice, pWH-A treated mice showed no acute skin response, mMCP-1 release or change in body temperature upon whey challenge in all centers, which corresponds with the absence of anaphylactic shock symptoms in both the mouse and guinea pig model. pWH-B and -C induced anaphylactic shock symptoms in the guinea-pig and mice whereas results on the remaining allergic outcomes in mice were inconclusive. No differences in microbiota composition were measured in response to the challenge and Microbiota composition depended on the location of the centers. CONCLUSIONS: Both animal models showed comparable results on the residual allergenicity of partial hydrolyzed whey proteins, but none of the centers was able to differentiate between the residual sensitizing capacities of the pWH-B and -C based on a single elicitation parameter in the murine model. Differences in microbiota composition might contribute to the robustness of the food allergy murine model. For a well-balanced prediction on the potential allergenicity of hydrolyzed infant formulas a multiple murine parameter model is suggested to decrease the risk of false positive or false negative results. A future challenge is to develop an overall scoring system for proper risk assessment, taking all parameters into account.

Mechanisms and immunomodulatory properties of pre- and probiotics.

The human body is exposed to many xenobiotic, potentially harmful compounds. The intestinal immune system is crucial in protecting the human body from these substances. Moreover, many microorganisms, residing in the gastrointestinal tract, play an important role in modulating immune responses. Pre- and probiotics may have beneficial effects on the microbial composition and activity within the human gut, subsequently affecting the immune system. Prebiotics can exert their effects via different mechanisms, like selectively stimulating the growth of bacteria by providing substrates or via direct immune stimulation. Probiotics may have beneficial health effects via competition with pathogens for substrates and binding intestinal sites, bioconversions of for example sugars into fermentation products with inhibitory properties, production of growth substrates like vitamins for the host, direct antagonism of pathogens via antimicrobial peptide production, reduction of inflammation and stimulation of immune cells. This review focuses on the different mechanisms via which the pre- and probiotics exert their beneficial effects on the host, addressing their immunomodulatory properties in particular.

[Conflicts between healthcare professionals and families of a multi-ethnic patient population in the intensive care unit]. / Conflict tussen zorgverleners en families van een multi-etnische patiëntenpopulatie op de IC.

OBJECTIVE: To investigate which factors contribute to conflicts between healthcare professionals and family members from ethnic minority groups during medically critical situations in hospital. DESIGN: Descriptive, ethnographic research. METHOD: Ethnographic fieldwork was carried out in one intensive care unit (ICU) of a multi-ethnic urban hospital in Belgium in the period January-June 2014. Data were collected by means of negotiated interactive observation, in-depth interviews with healthcare professionals and examining the patients' medical files. Data were analysed using grounded theory procedures. RESULTS: Conflicts were primarily related to the participants' different views on 'good care'. Healthcare providers' (HCPs') views on good care were primarily grounded on a biomedical care model, whereas families' views on good care were mainly inspired by a holistic care approach. According to HCPs, giving good care included fighting the disease efficiently with great scientific competence, but family members considered this rather as attending to the patient and giving bedside care, amongst other things. The HCPs' biomedical vision on good care was strengthened by the strict application of ward regulations, characterizing the ICU setting. The families' holistic views on good care were strengthened by specific ethno-familial characteristics, including their ethno-cultural background. However, ethno-cultural differences only contributed to conflict if the policy context on the ICU could provoke this conflict. CONCLUSION: Conflicts cannot be exclusively linked to ethno-cultural differences. Structural, functional characteristics of the ICU contribute substantially to conflict development. Effective conflict prevention should, therefore, not only focus on ethno-cultural differences but should also focus sufficiently on the structural context and ward policy.

Interlaboratory evaluation of a cow's milk allergy mouse model to assess the allergenicity of hydrolysed cow's milk based infant formulas.

This study describes two phases of a multi-phase project aiming to validate a mouse model for cow's milk allergy to assess the potential allergenicity of hydrolysed cow's milk based infant formulas (claim support EC-directive 2006/141/E). The transferability and the discriminatory power of this model was evaluated in 4 research centers. Mice were sensitized by oral gavage with whey or extensively hydrolysed whey (eWH) using cholera toxin as an adjuvant. Whey-specific antibodies, mMCP-1 levels, anaphylactic shock symptoms, body temperature and the acute allergic skin response were determined upon whey challenge. In phases I and II, all 4 centers detected elevated levels of whey-specific IgE/IgG1 in whey sensitized animals. Elevated levels of mMCP-1, anaphylactic symptoms, body temperature drop and acute allergic skin response were scored upon whey challenge in 3 out of 4 research centers. In contrast, none of the evaluated parameters were elevated in eWH orally exposed groups. The cow's milk allergy mouse model is capable to distinguish the sensitizing capacity of complete or hydrolysed cow's milk protein. The model uses straightforward parameters relevant to food allergic responses and can be effectively transferred between different laboratories. We propose this mouse model as a new strategy for the screening of new hypoallergenic cow's milk formulas.

CD4(+) CD25(+) T regulatory cells do not transfer oral tolerance to peanut allergens in a mouse model of peanut allergy.

BACKGROUND: Recent studies have implicated CD4(+) CD25(+) regulatory T cells (nTregs) in the maintenance of tolerance to oral antigens and in the regulation of the food allergic IgE response. OBJECTIVE: The objective was to assess if nTregs can transfer allergen-specific oral tolerance to naïve, non-TCR transgenic mice and regulate peanut extract (PE)-specific hypersensitivity responses. Additionally, the role of the regulatory cytokines IL-10 and TGF-ß in the modulation of peanut-allergic sensitization was studied. METHODS: CD25-enriched T cells from PE-tolerant mice were adoptively transferred to recipient mice, which were subsequently sensitized to PE. Depletion of CD25(+) cells and neutralization of IL-10 and TGF-ß were compared in a CH3/HeOuJ mouse model of peanut-allergic sensitization. RESULTS: Transfer of CD25(+) Tregs-enriched cell populations did not affect the PE-specific cytokine production or PE-specific antibody levels compared with control mice but interestingly resulted in a decrease of mast cell responsiveness. On the contrary, transfer of CD25(+) Tregs-depleted cells caused an increase in non-specific cytokine production, in the absence of changes in PE-specific responses. TGF-ß neutralization resulted even in a larger increase in spontaneous release of all cytokines measured (IL-4, IL-5, IL-10, IL-13, and IFN-γ), but surprisingly also to a higher PE-specific Th2-associated (IL-4, IL-5, IL-13) cytokine production compared with depletion of CD25 cells or neutralization of IL-10. Similarly, depletion of CD25 cells and TGF-ß neutralization but not of IL-10 neutralization lead to an increase in PE-specific antibody levels and elevated mast cell degranulation following a PE challenge. CONCLUSIONS AND CLINICAL RELEVANCE: We conclude that CD4(+) CD25(+) Tregs from non-transgenic-tolerant mice cannot transfer specific oral tolerance of exogenous antigens to naïve mice and are more involved in general immune suppressive mechanisms. However, we found evidence that TGF-ß secreting Tregs (Th3) may play an important role.

Evaluation of scientific criteria for identifying allergenic foods of public health importance.

Identification of allergenic foods of public health importance should be based on well-defined criteria. Björkstén et al. (2008) proposed that the criteria should assess the evidence for an IgE mechanism, the reaction, the potency and the severity of the effect of the food and its prevalence. This study evaluated the application of the proposed criteria based on published reports. Publications were selected from two databases to test whether the descriptions for ranking the level of evidence for each criterion were unambiguous and covered the full range of levels of evidence regarding seven foods, five known to be allergenic and two negative controls. The options available to rank the quality of evidence were appropriate but needed refinement to improve clarity and conceptual value. The criteria were helpful to assess known IgE-dependent allergens, and to exclude the non-allergenic substances. The criteria framework discriminated between papers with high, moderate and low quality of evidence. The advantage of using the proposed criteria is to make the decision-making process and rationale explicit. The framework helps to identify gaps in knowledge and to uncover the level of heterogeneity of the evidence thus guiding research and providing a basis for sound risk management decisions.

End-of-life care policies in Flemish residential care facilities accommodating persons with intellectual disabilities.

OBJECTIVE: This article aims to describe the presence, content and implementation strategies of written policies on end-of-life decisions in Flemish residential care facilities (RCFs) accommodating persons with intellectual disabilities (ID), and to describe training, education and quality assessments of end-of-life care. METHODS: A cross-sectional mail survey was conducted among general directors of all RCFs accommodating persons with ID (n = 140) in Flanders, Belgium. Institutions were asked to provide us with a copy of their end-of-life care policy documents for content analysis. RESULTS: Of the 140 institutions, 84 (60%) completed the questionnaire and 25 institutions provided 45 policy documents. Presence of policies on specific end-of-life decisions with a possible life-shortening effect lay between 18% (palliative sedation) and 26% (withdrawing or withholding of life-prolonging treatment). The content analysis showed that the focus in the majority of these policy documents is on palliative care, while end-of-life decisions with a possible life-shortening effect are mentioned but rarely elaborated on. Furthermore, few documents incorporate the distinctive features and needs of persons with ID regarding end-of-life care. On the other hand, half of the institutions trained and educated their professional care providers in some aspects of end-of-life care while one-third assessed the satisfaction of residents and families on several of these aspects. However, more than half reported explicitly that they have no plans for such assessments. CONCLUSIONS: The presence of end-of-life care policies is low in Flemish RCFs and their content is not very specific for persons with ID.

Deaths of children occurring at home in six European countries.

OBJECTIVES: Until now there have been no population-based European data available regarding place of death of children. This study aimed to compare proportions of home death for all children and for children dying from complex chronic conditions (CCC) in six European countries and to investigate related socio-demographic and clinical factors. METHODS: Data were collected from the death certificates of all deceased children aged 1-17 years in Belgium, the Netherlands, Norway, England, Wales (2003) and Italy (2002). Gender, cause and place of death (home vs. outside home) and socio-demographic factors (socio-economic status, degree of urbanization and number of hospital beds in the area) were included in the analyses. Data were analysed using frequencies and multivariate logistic regression. RESULTS: In total 3328 deaths were included in the analyses; 1037 (31.2%) related to CCC. The proportion of home deaths varied between 19.6% in Italy and 28.6% in the Netherlands and was higher for children dying from CCC in all the countries studied, varying between 21.7% in Italy and 50% in the Netherlands. Among children dying from CCC, home death was more likely for cancer patients and those aged over 10 years. After controlling for potentially related clinical and socio-demographic factors, differences in the proportion of home deaths between countries remained significant, with higher proportions in Belgium and the Netherlands as compared with Italy. CONCLUSIONS: Although home deaths comprise a substantial proportion of all deaths of children with CCCs, variation among disease categories and across countries suggest that considerable potential still exists for further improvements in facilitating end-of-life care in the home for those children and families who desire to be in this location.

Nurses' attitudes towards end-of-life decisions in medical practice: a nationwide study in Flanders, Belgium.

We investigated on a nationwide level the attitudes of nurses towards end-of-life decisions (ELDs) that may hasten death and towards their role in those decisions. We took a representative random sample of 6000 nurses in Flanders, Belgium. Response rate was 62.5%. Most nurses agreed with the practice of withholding/withdrawing potentially life-prolonging treatments (93%), with decisions to alleviate symptoms with possible life-shortening side effects (96%) and with the practice of euthanasia (92%). Their support for the different decisions existed regardless of whether they had cared for terminally ill patients or not. Most nurses also thought that they have an important role to play especially in the ELD-making process. Nurses' views on their proper role in the administration of drugs in euthanasia and continuous deep sedation showed a large dispersal. Overall, nurses' work setting determines their opinions on nurses' role in ELDs. In conclusion, nurses accept a wide variety of ELDs being practiced with terminally ill patients.

Information disclosure to terminally ill patients and their relatives: self-reported practice of Belgian clinical specialists and general practitioners.

Objective of this study is to examine physicians' practices regarding information disclosure to terminally ill patients and to their relatives, without informing the patient. A questionnaire had been sent to a random sample of 3014 Belgian physicians from different specialties frequently involved in end-of-life care. Responses were analysed using weighted percentages, Chi-square, Mann-Whitney U-tests and a multivariate ordinal logistic regression. Response rate was 58%. Both clinical specialists and general practitioners (GPs) discuss most topics related to terminal illness with their patients except end-of-life hastening options, spirituality, life expectancy and options to withhold/withdraw life-sustaining treatment. The topics which most physicians always discuss with relatives without informing the patient are the aim of treatment, palliative care and incurability. There is a significant difference between clinical specialists and GPs. Clinical specialists and GPs discuss most end-of-life topics with the patient but omit important issues such as end-of-life hastening options and life-expectancy.

Attitudes of Flemish secondary school students towards euthanasia and other end-of-life decisions in minors.

BACKGROUND: The aim of the study was to investigate attitudes of secondary school students towards acceptability of requests by minors for end-of-life decisions (ELDs) with a possible life-shortening effect: non-treatment decisions, potentially life-shortening alleviation of pain and symptoms (APS) and euthanasia. METHODS: A cross-sectional survey was conducted among second and fourth grades students in 20 secondary schools in Flanders, Belgium. An anonymous structured questionnaire was administered to measure attitudes towards acceptability of requests for euthanasia and other ELDs, towards the right to be informed about terminal prognosis and their own desire to be informed. RESULTS: In total, 1769 students participated. In case of a terminal patient, 61% found a request for euthanasia acceptable, 60% a request for APS and 69% a request for non-treatment decision, compared with 18% (euthanasia) and 50% (APS) in case of a non-terminal patient. Acceptance was highest among: boys, participants older than 14 years and participants from general as opposed to technical and vocational education. Sixty-six per cent said the parents' opinion not being asked was a circumstance that should hold back a physician from administering a lethal drug. Ninety per cent of participants thought a minor has the right to be informed about terminal prognosis of a disease while 78% would like to be informed themselves. CONCLUSIONS: Attitudes towards ELD requests varied with case and participant characteristics and type of ELD. The studied adolescents have a clear wish to be informed about terminal prognosis. Physicians and caregivers should adequately involve adolescents in decision making and tailor prognosis-related information to their needs and level of competency.

Population-based study of dying in hospital in six European countries.

This study examined the proportion of deaths taking place in hospitals in six European countries in relation to demographic, epidemiologic and healthcare factors. Retrospective analyses were performed on a database integrating death certificate data of all deaths in 2002 in Sweden and 2003 in Belgium, England, Scotland, the Netherlands and Wales (N = 891,780). Data were linked with regional healthcare statistics. Of all deaths, from 33.9% (the Netherlands) to 62.8% (Wales) occurred in hospital. Large country differences in hospital deaths were partly explained by the availability of care home and hospital beds. Differences between countries were strikingly large in older patients and cancer patients. Older patients had a higher probability of dying in hospital in Sweden, Scotland, England and Wales than in Flanders and, in particular, in the Netherlands. Cancer patients often died in hospitals in Sweden but less frequently so in the Netherlands and England. Country differences in the proportion of patients dying in hospital are only partly the result of differences in health care provision, and are in particular larger for certain patient categories, suggesting country-specific end-of-life practices in these categories. These findings can contribute to rational public health policies aimed at reducing hospital deaths.

Assessment of three human FcepsilonRI-transfected RBL cell-lines for identifying IgE induced degranulation utilizing peanut-allergic patient sera and peanut protein extract.

Specific IgE sera screening studies are employed to investigate protein cross-reactivity. Such nonfunctional immunochemical methods cannot measure the biological activity of proteins. Therefore, an assay using RBL cells transfected with human FcepsilonRI was developed. Our objective was to evaluate the degranulation of three cell-lines expressing either the alpha-(RBL-hEI(a)-2B12 and RBL-30/25cells) or alpha-, beta-, and gamma-subunits (RBL SX-38) of the human FcepsilonRI by beta-hexosaminidase release. Purified human IgE and serum-derived polyclonal IgE from peanut-allergic subjects following challenge with anti-IgE or peanut protein extract, respectively, were utilized. Robust degranulation was induced in all three: RBL-30/25 (84%), -hEI(a)-2B12 (54%), SX-38 (94%), respectively, using purified IgE+anti-human IgE. Good release (18%, 40-45%, and 65%, respectively) occurred for one peanut-allergic subject+peanut extract with all cell-lines. With serum from three other peanut-allergic subjects, no beta-hexosaminidase release occurred with RBL-hEI(a)-2B12 cells+peanut extract, while only serum from one subject induced good degranulation, 30% and 60%, respectively, with RBL-30/25 and RBL SX 38 cells. Consistent degranulation with a potent food allergen (peanuts) was not observed. The assay's utility in safety assessment, predictive value and reproducibility for evaluating the cross-reactivity of proteins with allergens needs further investigation with additional proteins and well-characterized sera.

Influence of physicians' life stances on attitudes to end-of-life decisions and actual end-of-life decision-making in six countries.

AIM: To examine how physicians' life stances affect their attitudes to end-of-life decisions and their actual end-of-life decision-making. METHODS: Practising physicians from various specialties involved in the care of dying patients in Belgium, Denmark, The Netherlands, Sweden, Switzerland and Australia received structured questionnaires on end-of-life care, which included questions about their life stance. Response rates ranged from 53% in Australia to 68% in Denmark. General attitudes, intended behaviour with respect to two hypothetical patients, and actual behaviour were compared between all large life-stance groups in each country. RESULTS: Only small differences in life stance were found in all countries in general attitudes and intended and actual behaviour with regard to various end-of-life decisions. However, with regard to the administration of drugs explicitly intended to hasten the patient's death (PAD), physicians with specific religious affiliations had significantly less accepting attitudes, and less willingness to perform it, than non-religious physicians. They had also actually performed PAD less often. However, in most countries, both Catholics (up to 15.7% in The Netherlands) and Protestants (up to 20.4% in The Netherlands) reported ever having made such a decision. DISCUSSION: The results suggest that religious teachings influence to some extent end-of-life decision-making, but are certainly not blankly accepted by physicians, especially when dealing with real patients and circumstances. Physicians seem to embrace religious belief in a non-imperative way, allowing adaptation to particular situations.

[Do-not-resuscitate policy on acute geriatric wards in Flanders, Belgium]. / Implementatie van niet-reanimeerbeleid op afdelingen acute geriatrie van Vlaamse ziekenhuizen in 2002 nog niet voltooid.

This study describes the historical development and status of a do-not-resuscitate (DNR) policy on acute geriatric wards in Flanders, Belgium. In 2002 (the year Belgium voted a law on euthanasia), a structured mail questionnaire was sent to all head geriatricians of acute geriatric wards in Flanders (N=94). Respondents were asked about the existence, development, and implementation of the DNR policy (guidelines and order forms). The response was 76.6%. Development of DNR policy began in 1985, with a step-up in 1997 and 200l. In 2002, a DNR policy was available in 86.1% of geriatric wards, predominantly with institutional DNR guidelines and individual, patient-specific DNR order forms. The policy was initiated and developed predominantly from an institutional perspective by the hospital. The forms were not standardized and generally lacked room to document patient involvement in the decision making process. Implementation of institutional DNR guidelines and individual DNR order forms on geriatric wards in Flanders lagged behind that of other countries and was still incomplete in 2002. DNR policies varied in content and scope and were predominantly an expression of institutional defensive attitudes rather than a tool to promote patient involvement in DNR and other end-of-life decisions.

[Medical end-of-life decisions in neonates and infants in Flanders, Belgium; 1999/2000]. / Medische beslissingen rond het levenseinde bij pasgeborenen en zuigelingen in Vlaanderen; 1991/'00.

OBJECTIVE: To determine the number of medical end-of-life decisions in critically ill neonates and infants in Flanders, Belgium. DESIGN: Retrospective. METHOD: A death certificate study on all deaths of neonates and infants in the whole of Flanders was carried out over a i2-month period (August 1999-July 2000). An anonymous questionnaire was sent by mail to the attending physician of each of the 292 children who died under the age of 1 year. All physicians who had attended at least one death during the study period were included in an attitude study. RESULTS: A total of 253 (87%) of the 292 questionnaires were returned and 121 (69%) of the 175 physicians involved completed the questions on attitude. An end-of-life decision had been possible in 194 (77%; 95% CI: 70.4-82.4) of the 253 deaths for which questionnaires were returned, and such a decision was actually made in 143 cases (57%; 95% CI: 48.9-64.0). Lethal drugs were administered in 15 of 117 early neonatal deaths and in 2 of 77 later deaths (13% versus 3%; p = 0.018). The attitude study showed that 69 (58%; 95% CI: 48.1-66.5) of the 120 physicians supported a change in the law making life-termination possible in some well-defined cases. CONCLUSION: The death of neonates and infants was commonly preceded by an end-of-life decision in Flanders. The type of decision varied substantially according to the age of the child. The majority of physicians involved, favoured legalization of the use of lethal drugs in some well-defined cases.

Drugs used for euthanasia in Flanders, Belgium.

PURPOSE: Our aim was to describe and assess the medicinal products and doses used for euthanasia in a series of cases, identified within an epidemiological death certificate study in Belgium, where euthanasia was until recently legally forbidden and where guidelines for euthanasia are not available. METHODS: In a random sample of the deaths in 1998 in Belgium, the physicians who signed the death certificates were identified and sent an anonymous mail questionnaire. The questionnaires of the deaths classified as euthanasia cases were reviewed by a multi-disciplinary panel. RESULTS: A total of 22 among 1925 questionnaires pertained to voluntary euthanasia. In 17 cases, detailed information on the euthanatics (medicinal substances used for euthanasia) used was provided. Opioids were used in 13 cases (in 7 as a single drug). Time between last dose and expiry ranged from 4 to 900 min. The panel judged that only in 4 cases effective euthanatics were used. CONCLUSIONS: In the end-of-life decision cases perceived by Belgian physicians as euthanasia, pharmacological practices were disparate, although dominated by the use of morphine, in the very late phase of dying, in doses which were unlikely to be lethal. Most physicians clandestinely engaging in euthanasia in Belgium seemed unaware of procedures for guaranteeing a quick, mild and certain death. Information on the pharmacological aspects of euthanasia should be included in the medical curriculum and continuing medical education, at least in countries with a legal framework permitting euthanasia under specified conditions.