Active clinical trials for "Hypersensitivity"

Investigation of the reactogenicity and immunogenicity of homologous and heterologous vaccine combinations with regard to the formation of SARS-CoV-2 antispike antibodies in health care workers after basic immunization and boost vaccination

Self-reported food hypersensitivity is common, particularly in women, with a reported prevalence of about 20% in the UK community. A wide range of gastrointestinal and systemic symptoms may be experienced related to consumption of the intolerant food(s). In addition, patients demonstrate considerably more generalized subjective health complaints in comparison with healthy controls. In this context, it has been reported that a consistent percentage of the general population consider themselves to be suffering from problems caused by wheat and/or gluten ingestion, even though they do not have celiac disease or wheat allergy. This clinical condition has been named non-celiac gluten sensitivity' (NCGS). In a previous paper the investigators suggested the term 'non-celiac wheat sensitivity' (NCWS), since it is not known what component of wheat causes the symptoms in NCGS patients, and the investigators also showed that these patients had a high frequency of coexistent multiple food hypersensitivity. In a previous study, the investigators demonstrated, in a population of teenagers, a frequency of self-reported NCWS of about 12%; the frequency of GFD use was 2.9%, which was much higher than the percentage of known CD in the same population (1.26%). The aims of this study were 1) to determine the prevalence of self-perceived wheat and/or gluten-sensitivity in patients undergoing digestive endoscopy, irrespective to the motivations of the test, and 2) to evaluate the demographic and clinical differences between patients self-reporting wheat and/or gluten sensitivity and patients not reporting food hypersensitivity.

Visceral hypersensitivity is frequent in IBS population up to 60% and is correlated with severity and altered quality of life. Sleeping troubles are most frequent in IBS population. Insomnia is a frequent disorder with an important cost for healthcare. Insomnia could decrease pain threshold. Visceral hypersensitivity was never measure in patients with insomnia. The hypothesis is IBS patients with insomnia probably have lower visceral pain threshold. The objective is to assess pain threshold during a barostat procedure in in IBS patients with or without insomnia in comparison with healthy volunteers or patients with insomnia. If the hypothesis are confirmed, insomnia should be look at in IBS patients and its treatments could improve visceral hypersensitivity and IBS symptoms.

PICOT elements:P: Teeth restored with indirect tooth colored restoration I: Immediate dentin sealing using universal adhesive C: Delayed dentin sealing O: Post-operative Hypersensitivity T: -Hypersensitivity assessment one week during provisionalization period and post-cementation S: Randomized Controlled Clinical Trial

Human visual acuity and contrast sensitivity are highly dependent on various different parameters. Each should be optimized for perfect visual performance. However, in real life our eyes lack such parameters, which might lead to unsatisfying results even after spectacle correction or contact lenses. A promising approach would be to design intra ocular lenses (IOL), which are implanted into the eye for example in the course of cataract extraction and are able to compensate for the human eyes' aberrations. For example cutoff frequency, edge-sharpness or specific contrast for selected structure sizes would need to be considered. Since, an aberration free optical system is almost impossible and since the impact of each single parameter is not yet known, IOL design parameters would have to be chosen very carefully. Furthermore, image quality of IOLs still is tested ex vivo by ray tracing for example, but this does not guarantee perfect function after implantation, as our visual system has complex image precessing units form the retina to the brain. The present study picks one of these parameters and seeks to assess its impact on visual quality in-vivo. By subjectively grading different images with objective changes to image quality by variations of the modulation transfer function (MTF), the potential influence and thus on our subjective visual impression shall be assessed.

The planned cohort study shall clarify whether the use of biomarkers leads to improved diagnostic assessment of elderly patients. The study will evaluate the clinical value of biomarkers (highly sensitive Troponin T, Troponin T of the 4th generation) in elderly patients. These biomarkers are analyzed together with the symptoms and other parameters collected at admission. The diagnosis of myocardial infarction could be made earlier and more accurately with the help of biomarkers, in particular the highly sensitive troponin T.

The most frequent diseases caused by wheat ingestion are T cell-mediated disorders, i.e. celiac disease and immunoglobulin E (IgE)-mediated allergic reactions. However, besides celiac disease and wheat allergy, there are cases of gluten reactions in which neither autoimmune nor IgE-mediated allergic mechanisms are involved. These are generally defined as GS or Not-celiac wheat sensitivity (NCWS). Typically, NCWS diagnosis is made by exclusion, and an elimination diet and an "open challenge" (i.e., the monitored reintroduction of gluten-containing foods) are most often used to evaluate whether health improves or worsen with the elimination or reintroduction of gluten in the diet, respectively. In some circumstances, it is very difficult to distinguish between NCWS and celiac disease. The presence of positive celiac disease specific serum antibodies (anti-tissue transglutaminase (anti-tTG), and anti-endomysium (EmAs) antibodies) is of paramount importance to pose the diagnosis. However, it is well known that the frequency of a positive serology is dependent by the severity of the intestinal damage. Consequently, patients with less severe histology damage (Marsh 1) can have negative serum antibodies. Previous studies had demonstrated that EmAs are produced by the intestinal lymphocytes and previous data from our group showed that EmAs assay in the culture medium of the intestinal biopsies has higher diagnostic accuracy than serum EmAs in diagnosis. Therefore, the aims of our study are to evaluate the clinical-serologic-histology course of NCWS patients, showing positive EmAs assay in the culture medium of the duodenal biopsies at the time of the first evaluation, and the adherence to a gluten-free diet in NCWS patients after a previous full evaluation and a NCWS diagnosis based on double-blinded placebo-controlled (DBPC) challenge.

Bovine β-lactoglobulin (Bos d 5) is an allergen from cow's milk with relevance to human health. We employed β-lactoglobulin polymerized using microbial transglutaminase as a model of study to identify whether protein polymerization could reduce in vivo allergenicity and maintain in vitro and ex vivo immunoreactivity for the purpose of producing a suitable molecule for use in tolerance-induction protocols. Based on previous protocols applied in mice and children, we performed in vivo challenges (using a skin prick test) with native and polymerized β-lactoglobulin in adult patients with an IgE-mediated allergy to Bos d 5. In vitro humoral immunoreactivity was analyzed using immunoblotting. Cell-mediated immunoreactivity was analyzed using ex vivo challenges with native and polymerized β-lactoglobulin monitored by leukocyte adherence inhibition tests. The study hypothesis is to identify a decrease on beta-lactoglobulin immunoreactivity after polymerization.

Age related cataracts are responsible for about 51 percent of blindness worldwide and according to the WHO affect about 20 million people, according to the WH . As cataract surgery is firstline treatment in the western world, there is a constant attempt to improve artificial intraocular lenes (IOL). As for this study, the investigators seek to compare four different IOL designs in in a psychophysiological setting, allowing to assess the impact of these IOLs on vision and psychological processing of visual information. As these IOLs also have downsides, such as reduced light intensity or image alterations, the subjective preference and overall impression shall be investigated. The healthy subjects look through a stable spectacle frame mounted onto a table, which enables the investigator to insert the different IOLs. This would allow subjective testing of IOLs before surgery.

Epigenetic mechanisms have been implicated in the pathogenesis of food allergy. The investigators previously demonstrated that tolerance acquisition in children with Immunoglobulin E- (IgE) mediated cow's milk allergy (CMA) is driven by epigenetic modulation of the Th1 and Th2 cytokine genes. A regulatory T cell (Treg) suppressive phenotype, characterized by stable expression of the transcription factor "Forkhead box Protein 3" (FoxP3), plays a pivotal role in food tolerance. FoxP3 mRNA expression is lower in children with atopic asthma or IgE-mediated food allergy than in healthy children. FoxP3 stable expression requires full CpG demethylation of its transcriptional regulatory regions, and, moreover, hypermethylation of the FoxP3 gene has been associated with reduced Treg function and allergy. DNA methylation is a biologically and chemically stable epigenetic modification that locks in long-term gene expression patterns. The demethylation status of FoxP3 at a highly conserved region within the Treg-specific-demethylated-region (TSDR), a CpG-rich, located on the 2nd conserved non-coding sequence of FoxP3 (CNS2), is restricted to Tregs. Transcriptional activity of the TSDR is essentially determined by its methylation status : it is completely inactive in its methylated state, but when the TSDR is demethylated, transcription factors such as Ets-1 and Creb can bind to the TSDR. TSDR demethylated and open chromatin conformation in the Foxp3 locus leads to stable phenotype differentiated Foxp3+ Treg. FoxP3 TSDR demethylation in peripheral blood mononuclear cells (PBMCs) has been associated with reduced atopic sensitization and asthma in children. Epigenetic regulation of antigen-induced T-cell subsets may predict a state of immune tolerance in food allergy. Indeed, DNA methylation of the FoxP3 gene in Tregs decreased during oral tolerance acquisition in patients with peanut allergy undergoing oral immunotherapy. The aim of this study was to evaluate further the epigenetic regulation of FoxP3 gene in children with IgE-mediated CMA.