[Food Allergy and Intolerance : Distinction, Definitions and Delimitation]

The clinical significance of allergen-specific IgG4 in allergic diseases

IgG4 is a subclass of IgG antibody with a unique molecular feature of (Fragment antigen- binding) Fab-arm exchange, allowing bispecific antigen binding in a mono-valent manner. With low binding affinity to C1q and Fcγreceptors, IgG4 is incapable of forming immune complexes and activating the complement pathway, exhibiting a non-inflammatory feature. IgG4 is produced similarly to IgE and is considered a modified reaction to IgE class-switching response under certain conditions. It could also counteract IgE-activated inflammation. However, the clinical significance of IgG4 in allergic diseases is complex and controversial. Three viewpoints have been suggested to describe the role of IgG4. IgG4 can act as a tolerance-inducer to play a protective role under repeated and rapid incremental dosing of allergen exposure in allergen immunotherapy (AIT), supported by allergies in cat raisers and venom desensitization in beekeepers. Another viewpoint accepted by mainstream specialists and guidelines of Food Allergy and Management in different countries points out that food-specific IgG4 is a bystander in food allergy and should not be used as a diagnostic tool in clinical work. However, eosinophilic esophagitis (EoE) investigation revealed a direct clinical relevance between physiopathology and serum IgG4 in cow milk and wheat. These factors indicate that allergen-specific IgG4 plays a multifaceted role in allergic diseases that is protective or pathogenic depending on different allergens or exposure conditions.

Prevalence of anxiety and its associated factors among infertile patients after 'two-child' policy in Chongqing, China: a cross-sectional study

BACKGROUND

With the prevalence of infertility increasing every year around the world, it has seriously impacted the individual quality of family and social life. Anxiety is one of the most prevalent anxiety disorders among infertile patients. After the two-child policy, whether it affected the prevalence of anxiety is controversial. This study aimed to determine the prevalence of anxiety and its potential risk factors among Chinese infertile women after the enforcement of 'two-child policy'.

METHODS

This cross-sectional study included 693 infertile patients in a reproductive medical center in Chongqing, China, between February 2016 and December 2018. Data was collected by Self-filling questionnaires including basic demographic information and the Generalized Anxiety Disorder-7 (GAD-7). SPSS statistical software (IBM SPSS version 25) was used to analyse the obtained data. Descriptive analysis was used to describe basic information and anxiety scores, the chi-square test and binary logistic regression were used to analyse the relationship between anxiety and other variables.

RESULTS

The prevalence of anxiety among total infertile patients was 21.8%, and its 23.5% among first-child infertile patients (FI), and 18.4% among second-child infertile patients (SI) respectively (P > 0.05). Binary logistic regression showed that patients with lower education levels were more likely to have anxiety (P < 0.01). Patients with middle salary incomes were more likely to have anxiety (OR = 1.860, 95% CI: 1.068-3.238). Oral contraception taking history (OR = 1.778, 95% CI: 1.186-2.667), and history of allergy (OR = 2.098, 95% CI: 1.219-3.612) were associated with anxiety.

CONCLUSIONS

Under the full liberalization of the "two-child policy", the total prevalence of anxiety among Chinese infertile female is comparatively high. Low education levels, middle incomes, oral contraception taking and allergy history can be the related risk factors of anxiety. We promote that all infertile patients should be evaluated for the prevalence of anxiety, especially those with potential risks, and receive consultant or targeted treatment when needed.

Intragastric Administration of Casein Leads to Nigrostriatal Disease Progressed Accompanied with Persistent Nigrostriatal-Intestinal Inflammation Activited and Intestinal Microbiota-Metabolic Disorders Induced in MPTP Mouse Model of Parkinson's Disease

Gut microbial dysbiosis and alteration of gut microbiota composition in Parkinson's disease (PD) have been increasingly reported, no recognized therapies are available to halt or slow progression of PD and more evidence is still needed to illustrate its causative impact on gut microbiota and PD and mechanisms for targeted mitigation. Epidemiological evidence supported an association between milk intake and a higher incidence of Parkinson's disease (PD), questions have been raised about prospective associations between dietary factors and the incidence of PD. Here, we investigated the significance of casein in the development of PD. The mice were given casein (6.75 g/kg i.g.) for 21 days after MPTP (25 mg/kg i.p. × 5 days) treatment, the motor function, dopaminergic neurons, inflammation, gut microbiota and fecal metabolites were observed. The experimental results revealed that the mice with casein gavage after MPTP treatment showed a persisted dyskinesia, the content of dopamine in striatum and the expression of TH in midbrain and ileum were decreased, the expression of Iba-1, CD4, IL-22 in midbrain and ileum increased continuously with persisted intestinal histopathology and intestinal barrier injury. Decreased intestinal bile secretion in addition with abnormal digestion and metabolism of carbohydrate, lipids and proteins were found, whereas these pathological status for the MPTP mice without casein intake had recovered after 24 days, no significant differences were observed with regard to only treated with casein. Our study demonstrates that intestinal pathologic injury, intestinal dysbacteriosis and metabolism changes promoted by casein in MPTP mice ultimately exacerbated the lesions to dopaminergic neurons.

Circadian profiling reveals higher histamine plasma levels and lower diamine oxidase serum activities in 24% of patients with suspected histamine intolerance compared to food allergy and controls

Background

Histamine intolerance is thought to trigger manifold clinical symptoms after ingesting histamine‐rich food due to reduced activity of diamine oxidase (DAO). No study has hitherto systematically assessed daily fluctuations of histamine levels and DAO activities in symptomatic patients. The aim of the study was to investigate the presence of histamine intolerance, to therefore establish day profiles of histamine levels and DAO activities, and to compare the results between patients with suspected histamine intolerance, food allergy and healthy controls.

Methods

We determined day profiles of histamine plasma levels and DAO serum activities in 33 patients with suspected histamine intolerance, in 21 patients with proven food allergy and in 10 healthy control patients. Clinical symptoms, food intolerances and further clinical and laboratory chemical parameters were evaluated.

Results

Twenty‐four percent (8 of 33) suspected histamine‐intolerant patients showed elevated histamine levels during the day. That might be caused by constantly and significantly reduced DAO activities in these patients compared to food‐allergic and control patients. The remaining 25 patients presented normal histamine levels and DAO activities, but an increased prevalence of multiple food intolerances compared to the other subgroup of suspected histamine‐intolerants. There was no correlation between subjective complaints and serological histamine parameters in patients with suspected histamine intolerance.

Conclusions

We determined by daily profiling that decreased DAO activities correlated with elevated histamine levels in a subgroup of suspected histamine‐intolerants. This finding discriminates these patients from food intolerant individuals with similar clinical symptoms and strongly suggests the presence of histamine intolerance.

Adverse reactions to food: the female dominance - A secondary publication and update

Gender-specific differences are evident in food intolerance and allergy. In this review, we will highlight and summarize the dissimilarities in prevalence of adverse food reactions, focusing on IgE-mediated food allergies and intolerances regarding frequency of symptoms and predisposing factors. After puberty, females suffer more frequently from food-related symptoms than males. Several factors may be responsible for this observation, for example hormonal effects, gender-specific behavior, perception of risk, or intake of medications. In this context, concrete studies related to adverse food reactions are still lacking.