MRGPRX2 and Immediate Drug Hypersensitivity: Insights From Cultured Human Mast Cells.

BACKGROUND AND OBJECTIVES: Mast cell (MC) degranulation via activation of the Mas-related G protein-coupled receptor X2 (MRGPRX2) plays a key role in immediate drug hypersensitivity (IDH). However, data in humans are limited to observations in specific cell lines. Objective: To study the usefulness of silencing MRGPRX2 in human MCs with the aim of further unveiling the MRGPRX2 pathway in IDH. METHODS: MCs were cultured from CD34+ progenitor cells obtained from peripheral blood (PBCMCs) and incubated with substance P (as a positive control), rocuronium, moxifloxacin, morphine, or amoxicillin. Immunophenotyping of the cells included flow cytometry and microscopy analyses of the expression of CD117, CD203c, and MRGPRX2. Intracellular calcium was measured using Fluo-4. Degranulation was analyzed by quantifying CD63 expression. For MRGPRX2 silencing, MCs were electroporated with Dicer small interference RNAs. RESULTS: Incubation of MCs with substance P, morphine, and moxifloxacin increased intracellular calcium levels and triggered MC degranulation, which, for the drugs, is almost completely abolished by selective MRGPRX2 silencing. Despite an increase in intracellular calcium in MRGPRX2+ cells, incubation with nontoxic concentrations of rocuronium does not result in degranulation of PBCMCs. Amoxicillin has no effect on PBCMCs. CONCLUSION: The use of MRGPRX2 silencing in human MCs can provide important insights into the role of MRGPRX2 in the pathogenesis of IDH. As induction of calcium signals does not necessarily translate into a secretory response, measurement of the degranulation reaction seems more meaningful in the context of drug testing.

[Impact on quality of life and autonomy of patients aged over 75 years treated with anti-PD-1 for metastatic melanoma: A single-centre prospective study]. / Impact sur la qualité de vie et l'autonomie des patients de plus de 75 ans traités par anti-PD-1 pour un mélanome métastatique : étude prospective monocentrique.

INTRODUCTION: We previously studied anti-PD-1 safety in elderly (≥80 years) patients and reported a retrospective two-centre cohort with a similar safety profile in elderly and in younger patients. Quality-of-life evaluation data is still lacking in this specific population. MATERIALS AND METHODS: A prospective, single-centre study in patients aged over 75 years presenting metastatic melanoma treated with anti-PD-1. The endpoint was monitoring of quality of life (by a specific survey) and onco-geriatric assessment at the beginning of therapy, then at 3 and 6 months (nutritional status, comorbidities, autonomy, thymic and cognitive disorders). RESULTS: Fourteen patients were included of median age 86.5 years [range: 78-94] from March to September 2018. General status was good, with a median Charlson score of 0 [extremes 0-4]. Nine patients were evaluated at 3 months and six patients at 6 months. There was no significant difference in quality-of-life scores obtained at baseline, 3 months and 6 months. DISCUSSION: This study shows that neither quality of life nor autonomy appears to be affected by anti-PD-1 treatment in patients aged over 75 years. However, these results should be interpreted with caution due to the small number of patients included, the short follow-up period and the single-centre data. Nevertheless, the prospective analysis and the complete onco-geriatric evaluation and monitoring yielded unique and original data.

[Effectiveness of anti-stigma interventions regarding severe mental illness: a systematic literature review]. / Effectiviteit van interventies tegen stigma van ernstige psychiatrische aandoeningen; systematisch literatuuroverzicht.

BACKGROUND: Stigma is one of the greatest challenges facing people with severe mental illness (smi) and can have profound psychological, social and professional consequences.
AIM: To systematically review the evidence of effectiveness of anti-stigma interventions (anti-stigma campaigns and specific interventions to reduce public stigma and self-stigma) for people with smi and to make recommendations for clinical practice.
METHOD: A systematic literature search for individual studies and reviews concerning the efficacy of interventions that reduce stigma for people with smi.
RESULTS: Anti-stigma interventions have small-to-medium effects. Although head-to-head comparisons do not show a clear advantage for educational or contact interventions, results suggest that the elements of contact, recovery and continuity (for public stigma) and psycho-education (for self-stigma) may yield the greatest effects. Due to the short follow-up period of most studies, there is limited evidence on the long-term effectiveness of these interventions. More specifically, it remains unknown whether these interventions lead to changes in actual behavior.
CONCLUSION: Anti-stigma interventions have limited effects on knowledge, attitudes and behavior. Several methodological shortcomings, as well as short follow-up periods in most studies, preclude making firm conclusions.

Immediate moxifloxacin hypersensitivity: Is there more than currently meets the eye?

Immediate drug hypersensitivity reactions (IDHR) to moxifloxacin constitute a pathomechanistic conundrum and a diagnostic challenge. Our objective was to study whether simultaneous phenotyping and quantification of histamine release might add to our knowledge about the basophil activation properties of moxifloxacin and constitute a reliable diagnostic aid. Fifteen patients with an IDHR to moxifloxacin and nine moxifloxacin challenged controls were selected. All had a basophil activation test (BAT) with moxifloxacin. Flow cytometric analysis of basophil responses implied labeling for CD63, CD203c, and intracellular histamine. Unlike tolerant challenged controls, basophilic upregulation of CD203c in response to moxifloxacin was observed in seven of 15 patients. Only two of these seven patients demonstrated appearance of CD63 and release of histamine. In the remainder eight patients, no basophil responses were demonstrable. In conclusion, immediate hypersensitivity to moxifloxacin might involve mechanisms difficult to capture by traditional CD63-/CD203c-based BAT. Deciphering the complexity of quinolone IDHR seems mandatory.

Cannabis sativa allergy: looking through the fog.

IgE-mediated Cannabis (C. sativa, marihuana) allergy seems to be on the rise. Both active and passive exposure to cannabis allergens may trigger a C. sativa sensitization and/or allergy. The clinical presentation of a C. sativa allergy varies from mild to life-threatening reactions and often seems to depend on the route of exposure. In addition, sensitization to cannabis allergens can result in various cross-allergies, mostly for plant foods. This clinical entity, designated as the 'cannabis-fruit/vegetable syndrome', might also imply cross-reactivity with tobacco, natural latex and plant-food-derived alcoholic beverages. Hitherto, these cross-allergies are predominantly reported in Europe and appear mainly to rely upon cross-reactivity between nonspecific lipid transfer proteins or thaumatin-like proteins present in C. sativa and their homologues, ubiquitously distributed throughout plant kingdom. At present, diagnosis of cannabis-related allergies predominantly rests upon a thorough history completed with skin testing using native extracts from crushed buds and leaves. However, quantification of specific IgE antibodies and basophil activation tests can also be helpful to establish correct diagnosis. In the absence of a cure, treatment comprises absolute avoidance measures. Whether avoidance of further use will halt the extension of related cross-allergies remains uncertain.

Evaluating galactic cosmic ray environment models using RaD-X flight data.

Galactic cosmic rays enter Earth's atmosphere after interacting with the geomagnetic field. The primary galactic cosmic rays spectrum is fundamentally changed as it interacts with Earth's atmosphere through nuclear and atomic interactions. At points deeper in the atmosphere, such as at airline altitudes, the radiation environment is a combination of the primary galactic cosmic rays and the secondary particles produced through nuclear interactions. The RaD-X balloon experiment measured the atmospheric radiation environment above 20 km during 2 days in September 2015. These experimental measurements were used to validate and quantify uncertainty in physics-based models used to calculate exposure levels for commercial aviation. In this paper, the Badhwar-O'Neill 2014, the International Organization for Standardization 15390, and the German Aerospace Company galactic cosmic ray environment models are used as input into the same radiation transport code to predict and compare dosimetric quantities to RaD-X measurements. In general, the various model results match the measured tissue equivalent dose well, with results generated by the German Aerospace Center galactic cosmic ray environment model providing the best comparison. For dose equivalent and dose measured in silicon, however, the models were compared less favorably to the measurements.

Efficacy of mast cell directed therapies in irritable bowel syndrome: a systematic review.

Background and study aim: Lately, mast cells (MCs) are increasingly implicated in the pathophysiology of irritable bowel syndrome (IBS). The aim of this systematic review was to assess the efficacy of mast cell directed therapies in reducing the main symptoms of IBS: abdominal pain and changes in stool frequency or consistency. Patients and methods: Pubmed, Web of Science and Scopus were searched until December 19, 2022. Trials evaluating the efficacy of mast cell directed therapies, compared to placebo or any form of control group, were included. Trial selection was performed in two stages: screening titles and abstracts and reviewing full papers identified as relevant, taking into account the inclusion criteria. Results: The search strategy identified a total of 1.384 citations. Eleven trials on 943 IBS patients and 197 controls were included: ten randomized controlled trials, two of which cross-over trials, and one cohort study. Of the 11 studies included in the systematic review, only three studies were found to be at low risk of bias. This limited evidence suggests a significant overall improvement in the key symptoms after treatment with disodium cromoglycate, ebastine, ketotifen or palmitoylethanolamide-polydatin compared to control groups. Conclusions: Mast cell modulating therapies could be of significant value in therapy for IBS patients. Further high-quality research is needed to establish the therapeutic efficacy of mast cell targeted therapies in order to draw robust conclusions and improve the clinical management of irritable bowel syndrome.

A novel approach for connecting temporal-ontologies with blood flow simulations.

In this paper an approach for developing a temporal domain ontology for biomedical simulations is introduced. The ideas are presented in the context of simulations of blood flow in aneurysms using the Lattice Boltzmann Method. The advantages in using ontologies are manyfold: On the one hand, ontologies having been proven to be able to provide medical special knowledge e.g., key parameters for simulations. On the other hand, based on a set of rules and the usage of a reasoner, a system for checking the plausibility as well as tracking the outcome of medical simulations can be constructed. Likewise, results of simulations including data derived from them can be stored and communicated in a way that can be understood by computers. Later on, this set of results can be analyzed. At the same time, the ontologies provide a way to exchange knowledge between researchers. Lastly, this approach can be seen as a black-box abstraction of the internals of the simulation for the biomedical researcher as well. This approach is able to provide the complete parameter sets for simulations, part of the corresponding results and part of their analysis as well as e.g., geometry and boundary conditions. These inputs can be transferred to different simulation methods for comparison. Variations on the provided parameters can be automatically used to drive these simulations. Using a rule base, unphysical inputs or outputs of the simulation can be detected and communicated to the physician in a suitable and familiar way. An example for an instantiation of the blood flow simulation ontology and exemplary rules for plausibility checking are given.

[Therapeutic strategies for the reconstruction of extensive mandibular defects]. / Behandlungskonzepte zur Rekonstruktion bei ausgedehnten Unterkieferdefekten.

Tumours of the mandibular bone or adjacent soft tissue often necessitate mandibular resection. Subsequent primary bone reconstruction to achieve optimal functional and aesthetic results has been made possible by microvascular surgical techniques and now represents the international gold standard. Microvascular reanastomosis of autologous bone grafts from the iliac crest or fibula is the most common procedure for reconstruction of the mandible. The localisation and extent of the expected defect, as well as a patient's overall condition and ability to tolerate long surgical procedures must be carefully considered before deciding upon the course of treatment. Additional microvascular reanastomosis of soft tissue flaps and stereolithographic models facilitate preoperative planning and broaden the surgical spectrum. Following successful reconstruction of the bone, insertion of dental implants and prosthetic rebuilding are required to complete rehabilitation, including restoration of the patient's ability to chew and speak. The authors recommend specialised oncologic centres for such complex surgical reconstructions.

Screening older cancer patients: first evaluation of the G-8 geriatric screening tool.

BACKGROUND: Development of a geriatric screening tool is necessary to identify elderly cancer patients who would benefit from comprehensive geriatric assessment (CGA). We develop and evaluate the G-8 screening tool against various reference tests. PATIENTS AND METHODS: Analyses were based on 364 cancer patients aged>70 years scheduled to receive first-line chemotherapy included in a multicenter prospective study. The G-8 consists of seven items from the Mini Nutritional Assessment (MNA) questionnaire and age. Our primary reference test is based on a set of seven CGA scales: Activities Daily Living (ADL), Instrumental ADL, MNA, Mini-Mental State Exam, Geriatric Depression Scale, Cumulative Illness Rating Scale-Geriatrics, and Timed Get Up and Go. We considered the presence of at least one questionnaire with an impaired score as an abnormal reference exam. Additional reference exams are also discussed. RESULTS: The prevalence of being at risk varied from 60% to 94% according to the various definitions of the reference test. When considering the primary reference test, a cut-off value of 14 for the G-8 tool provided a good sensitivity estimate (85%) without deteriorating the specificity excessively (65%). CONCLUSION: The G-8 shows good screening properties for identifying elderly cancer patients who could benefit from CGA.

Plakophilins 2a and 2b: constitutive proteins of dual location in the karyoplasm and the desmosomal plaque.

Using antibodies and recombinant DNA techniques, we have identified plakophilin 2, a novel desmosomal plaque protein of M(r) 100,000 (estimated from SDS-PAGE), which is a member of the arm-repeat family of proteins and can occur in two splice forms (2a and 2b) because of the insertion of a 44 amino acid (aa)-encoding exon. In its aa sequence (837 and 881 aa, calculated pIs: 9.33 and 9.38, mol wts 92,750 and 97,410 kD), it is conspicuously related to the 80-kD plakophilin 1, with which it shares a central region of 9 repeats of the arm-motif, preceeded by a long head region and followed by a very short (11 aa) carboxy-terminal sequence. Plakophilin 2 and its mRNA have been detected in a wide range of tissues and cell types, including cells devoid of desmosomes. By light and electron microscopical immunolocalization, plakophilin 2 has been localized to plaques of desmosomes of one-layered ("simple") and complex epithelia, carcinomas, diverse epithelium-derived cell culture lines, as well as cardiac tissue and the dendritic reticulum cells of lymphatic germinal centers, i.e., desmosomes in which plakophilin 1 is not detected. However, plakophilin 2 has also been localized in the desmosomes of certain but not all stratified epithelia where it coexists with plakophilin 1. Remarkably, plakophilin 2 is also enriched in the karyoplasm of a wide range of cell types, including many that lack desmosomes and in which, therefore, the nuclear state is the only locally enriched form of plakophilin 2 present. We conclude that plakophilins 2a and 2b are basic nuclear proteins that in certain cell types additionally assemble with other proteins to form the desmosomal plaque and serve general nuclear functions as well as a function specific to many but not all desmosomes.

Long-term donor site morbidity in head and neck cancer patients and its impact on quality of life: a cross-sectional study.

Modern head and neck reconstructive surgery offers a multitude of different reconstructive options. In such cases, donor site morbidity is an important factor in the affected patient's decision-making. The aim of this study was to perform an objective comparison of donor site morbidity for the five most frequent microvascular donor sites in head and neck reconstructive surgery (radial forearm, anterolateral thigh, fibula, iliac crest, and scapula) using a uniform testing system. In this cross-sectional study, 117 donor sites were analyzed (106 for malignant disease and 11 for non-malignant disease): 73 radial forearm, 14 scapula, 12 anterolateral thigh, 10 fibula, and eight iliac crest. Testing consisted of range of motion, muscle strength, and sensation. The non-affected side served as the control. Quality of life was assessed using the Washington Quality of Life Questionnaire version 4 in its German translation. Range of motion was restricted in 15 cases (12.8%). Muscle strength was decreased in 58 cases (49.6%). Sensation was reduced in 70 cases (60%). Concerning quality of life, 31.2% of patients were limited in their daily activities. The scapula flap showed the highest incidence of overall donor site morbidity. However, correlation between objective and subjective donor site impairment was weak and the majority of patients experienced only minor limitations.

[The German keratomycosis registry : Initial results of a multicenter survey]. / Das Deutsche Pilz-Keratitis-Register : Erste Ergebnisse einer multizentrischen Erhebung.

BACKGROUND AND PURPOSE: Mycotic keratitis is a serious but relatively rare disease. No targeted data collection in Germany existed until the foundation of the German Pilz-Keratitis Register in 2015. PATIENTS AND METHODS: The inclusion of retrospective and prospective patients was carried out. INCLUSION CRITERIA: diagnosis confirmed by the polymerase chain reaction (PCR), culture, histology or confocal microscopy (IVCM). Collected parameters: date of symptom onset, date and method of diagnosis, risk factors, visual acuity and findings at admission and at follow-up, conservative and surgical treatment. RESULTS: By January 2018, a total of 102 eyes from the years 2000-2017 were reported from 16 centers (64.3% female, mean age 52 years, range 18-95 years). The initial diagnosis was made correctly in only 20.6% of cases. The mean time to correct diagnosis was 31.7 ±â€¯46.9 (0-296) days. The diagnosis was confirmed in cultures in 74.5%, histologically in 30.4%, by PCR in 38.2% and IVCM in 27.4%. Fungal species identified were: 36.7% Fusarium spp., 35.8% Candida spp., 6.4% Aspergillus spp. and 21.1% other. The most important risk factor was the use of contact lenses. The most commonly used antifungal agent was voriconazole (64.7%) followed by amphotericin B (37.2%). Penetrating keratoplasty was performed in 65.7% of the cases and 8.8% of the affected eyes had to be enucleated. The visual acuity of the entire study population increased from the initial 0.16 ±â€¯0.25 (0.001-1.0) decimal to 0.28 ±â€¯0.34 (0-1.0) decimal. CONCLUSION: The correct diagnosis of fungal keratitis is often significantly delayed. The treatment can be very difficult and keratoplasty is often necessary. In order to gain a better understanding of this disease, to recognize previously unknown risk factors and, if necessary, a change in the spectrum of pathogens and to identify approaches to treatment optimization, the fungal keratitis registry will be continued.

[Paranoia and Asperger syndrome]. / Paranoia en het aspergersyndroom.

Paranoia in patients diagnosed with Asperger syndrome in adulthood is discussed and illustrated with the help of a case study. Impaired mentalisation, characteristic for Asperger disorder, influences the way an individual experiences life, making him more vulnerable for the development of delusional beliefs.

[Hypofractionad radiotherapy for elderly with head and neck cancer]. / Radiothérapie hypofractionnée des cancers ORL chez le sujet âgé.

Thirty percent of patients with head and neck cancer are over 70 years. Radiotherapy approach in elderly is a challenge. On one hand, radiotherapy side effects, as well as the number of sessions required, could be a burden. On the other hand, omission of local treatment is not an option due to the symptoms of the tumor. Patients in good general condition may receive standard fractionnated radiotherapy. For frail patients unsuitable for standard fractionated radiotherapy, more convenient shorter course of radiotherapy are commonly used. Physicians have to choose the best radiotherapy schedule according to the objective of the treatment. In case of palliative intend: hypofractionated radiotherapy delivered with a single short course could be recommanded. This course could be followed by other subsequent courses if the patient's condition improves during the treatment. For patients treated in curative intend, the choice of hypofractionation schedule depends on the general condition: split course hypofractionated radiotherapy for unfit patients, or accelerated radiotherapy with concomitant boost for fit patients. In all cases, a high-quality radiotherapy technique and appropriate supportive care are mandatory to minimize the side effects. The ELAN RT trial, soon to be completed, will rule on the non-inferiority of hypofractionated radiotherapy compared to standard radiotherapy for unfit patients.

Prevalence and zoonotic risks of Trichophyton mentagrophytes and Cheyletiella spp. in guinea pigs and rabbits in Dutch pet shops.

Young rabbits and guinea pigs are often purchased as pets for children and may be infected with zoonotic skin infections. To assess the risk of acquiring such an infection from rabbits or guinea pigs, this study investigated the prevalence of the fungus Trichophyton mentagrophytes and the fur mite Cheyletiella parasitovorax in asymptomatic rabbits and guinea pigs in Dutch pet shops. In 91 pet shops a total of 213 rabbits and 179 guinea pigs were sampled using the Mackenzie technique and cultured. Clean cultures were examined microscopically and a PCR was performed on at least one sample from each pet shop. All animals were investigated for fur mite using a flea comb, a magnifying glass and white paper. From the fur of 3.8% (8/213) of the rabbits and 16.8% (30/179) of the guinea pigs, T. mentagrophytes was isolated. From 1 guinea pig (0,6%) Chrysosporium keratinophilum was isolated. Dermatophyte-positive rabbits and guinea pigs originated from 5.6% (5/90) and 27.3% (24/88) of the investigated pet shops, respectively. Fur mites were not found. Pet shops can play an important role in preventing transmission of zoonotic ringworm infections (dermatophytosis) and educating their customers. Specific preventive measures such as routine screening examinations and (prophylactic) treatment of rabbits and guinea pigs are recommended next to regular hygiene when handling animals.

In Vitro Diagnosis of Immediate Drug Hypersensitivity Anno 2017: Potentials and Limitations.

BACKGROUND: For most physicians, quantification of drug-specific immunoglobulin E (drug-sIgE) antibodies constitutes the primary in vitro measure to document immediate drug hypersensitivity reactions (IDHR). Unfortunately, this is often insufficient to correctly identify patients with IgE-mediated IDHR and impossible for non-IgE-mediated IDHR that result from alternative routes of basophil and mast cell activation. In these difficult cases, diagnosis might benefit from cellular tests such as basophil activation tests (BAT). AIM: The aim was to review the potential and limitations of quantification of sIgE and BAT in diagnosing IDHR. The utility of quantification of serum tryptase is discussed. METHODS: A literature search was conducted using the key words allergy, basophil activation, CD63, CD203c, diagnosis, drugs, hypersensitivity, flow cytometry, specific IgE antibodies; this was complemented by the authors' own experience. RESULTS: The drugs that have been most studied with both techniques are ß-lactam antibiotics and curarizing neuromuscular blocking agents (NMBA). For sIgE morphine, data are available on the value of this test as a biomarker for sensitization to substituted ammonium structures that constitute the major epitope of NMBA, especially rocuronium and suxamethonium. For the BAT, there are also data on non-steroidal anti-inflammatory drugs (NSAIDs) and iodinated radiocontrast media. For ß-lactam antibiotics, sensitivity and specificity of sIgE varies between 0 and 85% and 52 and 100%, respectively. For NMBA, sensitivity and specificity varies between 38.5 and 92% and 85.7 and 100%, respectively. Specific IgE to morphine should not be used in isolation to diagnose IDHR to NMBA nor opiates. For the BAT, sensitivity generally varies between 50 and 60%, whereas specificity attains 80%, except for quinolones and NSAIDs. CONCLUSIONS: Although drug-sIgE assays and BAT can provide useful information in the diagnosis of IDHR, their predictive value is not absolute. Large-scale collaborative studies are mandatory to harmonize and optimize test protocols and to establish drug-specific decision thresholds.