Do risk factors differentiate DSM-5 and drive for thinness severity groups for anorexia nervosa?

BackgroundThe current study examined whether risk factors for anorexia nervosa (AN) were related to different levels of severity based on (a) the DSM-5/body mass index (BMI) and (b) drive for thinness (DT) severity ratings.MethodsThe sample comprised 153 pairs of individuals with a lifetime diagnosis AN per DSM-IV criteria and their non-ED sisters (N = 306, mean age = 26.53; mean current BMI = 20.42 kg/m2). The Oxford risk factor interview was used to establish AN-related risk factors. Individuals were categorised into the DSM-5 severity groups based on their lowest BMI, while the DT subscale from the eating disorder inventory-2 was used to classify individuals with AN into low and high DT groups.ResultsMultinominal regression models showed similar risk factors (e.g., perfectionism, having a history of being teased about weight and shape) contributed to the development of AN using the DSM-5 and DT severity ratings. Follow-up analyses across the severity groups for both indices revealed that only childhood perfectionism was found to be more common in the extreme severe DSM-5 BMI severity group compared to the severe DSM-5 group.ConclusionOverall, this study found little evidence for AN risk factors being related to the DSM-5 and DT severity ratings. However, given the novelty of this study, replication of the current results is warranted. Several risk factors, such as childhood obesity, have been found to contribute to the development of Anorexia Nervosa (AN). Yet, we are unsure if there is a set of risk factors that influence different levels of AN severity. While the DSM-5 suggests using BMI to measure severity, recent support favour the usage of drive for thinness (DT) as an alternative severity measure. Therefore, this study aimed to explore risk factors specifically associated with the development of different AN severity levels using both the DSM-5 BMI and DT severity classification systems. We recruited 153 pairs of individuals with a lifetime diagnosis AN per DSM-IV criteria and their non-ED sisters. The Oxford risk factor interview was used to establish AN-related risk factors. We found childhood perfectionism, weight/shape teasing, childhood obesity, and breast-related embarrassment to be significant risk factors for AN. Additionally, childhood perfectionism was more common in the extreme severe DSM-5 group compared to the severe DSM-5 group. This suggests that adding perfectionism-related aspects to prevention and early intervention programs for AN may be beneficial. Considering the novelty of this study, replication of the current results is needed

Associations of individual and family eating patterns during childhood and early adolescence: a multicenter European study of associated eating disorder factors

The objective of this study was to examine whether there is an association between individual and family eating patterns during childhood and early adolescence and the likelihood of developing a subsequent eating disorder (ED). A total of 1664 participants took part in the study. The ED cases (n 879) were referred for assessment and treatment to specialized ED units in five different European countries and were compared to a control group of healthy individuals (n 785). Participants completed the Early Eating Environmental Subscale of the Cross-Cultural (Environmental) Questionnaire, a retrospective measure, which has been developed as part of a European multicentre trial in order to detect dimensions associated with ED in different countries. In the control group, also the General Health Questionnaire-28 (GHQ-28), the semi-structured clinical interview (SCID-I) and the Eating Attitudes Test (EAT-26) were used. Five individually Categorical Principal Components Analysis (CatPCA) procedures were adjusted, one for each theoretically expected factor. Logistic regression analyses indicated that the domains with the strongest effects from the CatPCA scores in the total sample were: food used as individualization, and control and rules about food. On the other hand, healthy eating was negatively related to a subsequent ED. When differences between countries were assessed, results indicated that the pattern of associated ED factors did vary between countries. There was very little difference in early eating behaviour on the subtypes of ED. These findings suggest that the fragmentation of meals within the family and an excessive importance given to food by the individual and the family are linked to the later development of an ED

Measuring kinetic drivers of pneumolysin pore structure

Most membrane attack complex-perforin/cholesterol-dependent cytolysin (MACPF/CDC) proteins are thought to form pores in target membranes by assembling into pre-pore oligomers before undergoing a pre-pore to pore transition. Assembly during pore formation is into both full rings of subunits and incomplete rings (arcs). The balance between arcs and full rings is determined by a mechanism dependent on protein concentration in which arc pores arise due to kinetic trapping of the pre-pore forms by the depletion of free protein subunits during oligomerisation. Here we describe the use of a kinetic assay to study pore formation in red blood cells by the MACPF/CDC pneumolysin from Streptococcus pneumoniae. We show that cell lysis displays two kinds of dependence on protein concentration. At lower concentrations it is dependent on the pre-pore topore transition of arc oligomers, which we show to be a cooperative process. At higher concentrations it is dependent on the amount of pneumolysin bound to the membrane and reflects the affinity of the protein for its receptor, cholesterol. A lag occurs before cell lysis begins; this is dependent on oligomerisation of pneumolysin. Kinetic dissection of cell lysis by pneumolysin demonstrates the capacity of MACPF/CDCs to generate pore-forming oligomericstructures of variable size with, most likely, different functional roles in biology

Does targeting Arg98 of FimH lead to high affinity antagonists?

Bacterial resistance has become an important challenge in the treatment of urinary tract infections. The underlying resistance mechanisms can most likely be circumvented with an antiadhesive approach, antagonizing the lectin FimH located at the tip of fimbriae of uropathogenic E. coli. Here we report on a novel series of FimH antagonists based on the 1-(α-d-mannopyranosyl)-4-phenyl-1,2,3-triazole scaffold, designed to incorporate carboxylic acid or ester functions to interact with FimH Arg98. The most potent representative of the series, ester 11e, displayed a K; d; value of 7.6 nM for the lectin domain of FimH with a general conclusion that all esters outperform carboxylates in terms of affinity. Surprisingly, all compounds from this new series exhibited improved binding affinities also for the R98A mutant, indicating another possible interaction contributing to binding. Our study on 1-(α-d-mannopyranosyl)-4-phenyl-1,2,3-triazole-based FimH antagonists offers proof that targeting Arg98 side chain by a "chemical common sense", i.e. by introduction of the acidic moiety to form ionic bond with Arg98 is most likely unsuitable approach to boost FimH antagonists' potency

Direct PIP2 binding mediates stable oligomer

The human serotonin transporter (hSERT) mediates uptake of serotonin from the synaptic cleft and thereby terminates serotonergic signalling. We have previously found by single-molecule microscopy that SERT forms stable higher-order oligomers of differing stoichiometry at the plasma membrane of living cells. Here, we report that SERT oligomer assembly at the endoplasmic reticulum (ER) membrane follows a dynamic equilibration process, characterized by rapid exchange of subunits between different oligomers, and by a concentration dependence of the degree of oligomerization. After trafficking to the plasma membrane, however, the SERT stoichiometry is fixed. Stabilization of the oligomeric SERT complexes is mediated by the direct binding to phosphoinositide phosphatidylinositol-4,5-biphosphate (PIP2). The observed spatial decoupling of oligomer formation from the site of oligomer operation provides cells with the ability to define protein quaternary structures independent of protein density at the cell surface.(VLID)459696

Additional file 1 of Do risk factors differentiate DSM-5 and drive for thinness severity groups for anorexia nervosa?

Additional file 1. Social and clinical related information of healthy sisters and individuals with AN