Effect of food stimuli presentation on restrained eater's food choice: An ERP study.

Restrained eaters are individuals who consciously follow a limited food intake diet to lose or maintain body weight. With the rising numbers of obesity cases, retrained eating has became more prevalent as more people adopt it to cope with obesity. The dual conflict theory states that restrained eaters often encounter conflicting choices of food pleasure and weight management. The present study investigated the difference in food choice regarding different presentations of the weight management goal. The study hypothesized difference in successful and unsuccessful restrained eaters' food choice when presented with the conflicting food/weight maintenance stimuli. A total of 49 college students participated in the study and the N2, P3 and LPP event-related potentials (ERPs) were investigated during a food choice task. Results showed that the reaction time in unsuccessful restrained eaters (UREs) were greater than successful restrained eaters (SREs). The ERP results showed that SREs exhibited smaller N2 and greater P3 amplitudes than UREs, however, we did not find a difference in LPP amplitudes between the two groups. The findings suggest that the UREs demonstrated greater sensitivity and smaller inhibition to food cues, while we do not have supports for a difference in motivational and emotional salience. This is the first study that investigated the food choice of SREs and UREs when faced with different presentations of conflicting goals, which enriches the theoretical model and provides neural correlates evidence for future studies.

Bacterial ghosts engineered with lipidated antigens as an adjuvant-free vaccine for Chlamydia abortus.

Bacterial ghosts (BGs) provide novel vaccine delivery platforms because of their inherent adjuvant properties and efficient antigen delivery capabilities. However, effective engineering strategies are required to modify them for different antigens. In this study, the Escherichia coli (E. coli) ghost was modified by using a lpp'-ompA chimera, a widely used bacterial surface display vector, with a protective antigen macrophage infectivity potentiator (MIP) of Chlamydia abortus (C. abortus), and its protective effect was evaluated in a mouse model. The MIP fusion protein accumulated at 1.2% of the ghost total protein mass and a significant portion of the protein was modified into lipoproteins upon translocation to the BG surface. Lipidated MIP-modified recombinant E. coli ghosts (rECG-lpp'-MIP) effectively promoted antigen-presenting cells (APCs) uptake of antigens and stimulated APCs activation in vivo and in vitro. Immunization with rECG-lpp'-MIP and no adjuvant induced intense specific humoral responses as well as Th1-biased cellular immune responses, which significantly improved the efficiency of C. abortus infection clearance in mice and reduced pathological damage to the uterus. In summary, this study demonstrates that recombinant E. coli ghosts modified with lipidated antigens could help to develop an effective C. abortus vaccine and aid in the development of a universal adjuvant-free vaccine platform.

Receivers' responses are integrated into costly third-party punishment in a way that interacts with the unfairness of allocations.

Costly third-party punishment (TPP) is an effective way to enforce fairness norms and promote cooperation. Recent studies have shown that the third party considers not only the proposer's suggested allocation but also the receiver's response to the allocation, which was typically ignored in traditional TPP studies when making punishment decisions. However, it remains unclear whether and how the varying unfair allocations and receivers' responses are integrated into third-party punishment. The current study addressed these issues at behavioral and electrophysiological levels by employing a modified third-party punishment task involving proposers' highly or moderately unfair allocations and the receivers' acceptance or rejection responses. At the behavioral level, participants punished proposers more often when receivers rejected relative to accepted unfair allocations. This effect was further modulated by the unfairness degree of allocations, indicated by a more pronounced rejection-sensitive effect when participants observed the moderately unfair offers. Electrophysiologically, when the receiver rejected the moderately unfair allocations, a stronger late-stage component P300/LPP, which was considered to be involved in allocations of attention resources, was found. Meanwhile, separated from the P300/LPP, the P200 associated with early attention capture demonstrated a rejection-sensitive effect. Together, in the costly TPP studies, the receiver is typically designated as passive and silent, and her/his responses to unfairness are conventionally ignored. However, our results indicate that except for the proposer's distribution behavior, the receiver's response does have an impact on third-party punishment in a way that interacts with the unfairness of allocations.

The influence of contextual uncertainty on facial expression processing: Evidence from behavior and ERPs.

The brain helps individuals build expectations based on emotional prediction, facilitating the processing of faces in social interactions. Due to the intricacy of the environment, accurately predicting emotions remains a formidable task. Contextual uncertainty represents a state characterized by the inability to predict when, how, and why events occur. It leads to intensified sentiments and triggers adverse emotions like anxiety. Therefore, comprehending the influences of contextual uncertainty carries importance. The present study utilized event-related potentials (ERPs) technology to investigate contextual uncertainty's influence on facial expression processing. We employed a novel S1-S2 paradigm, using scene images as S1 and faces as S2. From the learning phase into the testing phase, the certain to uncertain group (CER to UNC) experienced more unpredictability (increased uncertainty), whereas the uncertain to certain group (UNC to CER) experienced more predictability (decreased uncertainty). This allowed for manipulating dynamic alterations in predictive relationships. The behavioral results showed that the valence ratings of neutral facial expressions were more negative in the CER to UNC group with increased contextual uncertainty. The ERP results showed that the more negative SPN (stimulus preceding negativity) amplitudes and positive LPP (late positive potential) amplitudes were observed in the UNC to CER group with decreased contextual uncertainty, compared to the CER to UNC group with increased contextual uncertainty. These findings have indicated that contextual uncertainty affects facial expression processing. In summary, these results contributed to comprehending the contextual uncertainty.

The ineffective emotion regulation of deaf college students: an ERP study.

Introduction: Deaf students have more difficulties with emotion regulation due to their hearing loss. They are suffering higher socio-emotional risk than the hearing person. But there are few studies explored the neural mechanisms of impaired emotion regulation in the deaf college students. Methods: Thirty hearing college students and 27 deaf college students completed the emotion regulation task while recording ERP data and subjective emotion intensity. Results: Behavioral results found that deaf college students had higher emotional experience intensity compared to healthy controls. The ERP results showed the deaf college students had lower LPP amplitudes both using reappraisal and suppression strategies. Moreover, the LPP of expression suppression was associated with the increase of depression scores among deaf college students. Discussion: Deaf college students may have impaired emotion regulation so that they are more accustomed to using expression suppression strategies to regulate their negative emotions which lead to high risk to be depression.

EEG correlates of static and dynamic face perception: the role of naturalistic motion.

Much of our understanding of how the brain processes dynamic faces comes from research that compares static photographs to dynamic morphs, which exhibit simplified, computer-generated motion. By comparing static, video recorded, and dynamic morphed expressions, we aim to identify the neural correlates of naturalistic facial dynamism, using time-domain and time-frequency analysis. Dynamic morphs were made from the neutral and peak frames of video recorded transitions of happy and fearful expressions, which retained expression change and removed asynchronous and non-linear features of naturalistic facial motion. We found that dynamic morphs elicited increased N400 amplitudes and lower LPP amplitudes compared to other stimulus types. Video recordings elicited higher LPP amplitudes and greater frontal delta activity compared to other stimuli. Thematic analysis of participant interviews using a large language model revealed that participants found it difficult to assess the genuineness of morphed expressions, and easier to analyse the genuineness of happy compared to fearful expressions. Our findings suggest that animating real faces with artificial motion may violate expectations (N400) and reduce the social salience (LPP) of dynamic morphs. Results also suggest that delta oscillations in the frontal region may be involved with the perception of naturalistic facial motion in happy and fearful expressions. Overall, our findings highlight the sensitivity of neural mechanisms required for face perception to subtle changes in facial motion characteristics, which has important implications for neuroimaging research using faces with simplified motion.

EEG might be better left alone, but ERPs must be attended to: Optimizing the late positive potential preprocessing pipeline.

The late positive potential (LPP) is an ERP component commonly used to study emotional processes and has been proposed as a neuroaffective biomarker for research and clinical uses. These applications, however, require standardized procedures for elicitation and ERP data processing. We evaluated the impact of different EEG preprocessing steps on the LPP's data quality and statistical power. Using a diverse sample of 158 adults, we implemented a multiverse analytical approach to compare preprocessing pipelines that progressively incorporated more steps: artifact detection and rejection, bad channel interpolation, and bad segment deletion. We assessed each pipeline's effectiveness by computing the standardized measurement error (SME) and conducting simulated experiments to estimate statistical power in detecting significant LPP differences between emotional and neutral images. Our findings highlighted that artifact rejection is crucial for enhancing data quality and statistical power. Voltage thresholds to reject trials contaminated by artifacts significantly affected SME and statistical power. Once artifact detection was optimized, further steps provided minor improvements in data quality and statistical power. Importantly, different preprocessing pipelines yielded similar outcomes. These results underscore the robustness of the LPP's affective modulation to preprocessing choices and the critical role of effective artifact management. By refining and standardizing preprocessing procedures, the LPP can become a reliable neuroaffective biomarker, supporting personalized clinical interventions for affective disorders.

Evaluation of hair surface structure and morphology of patients with lichen planopilaris (LPP) by atomic force microscopy (AFM).

BACKGROUND: Lichen planopilaris (LPP) is a chronic lymphocytic skin disease manifested by progressive scarring alopecia. The diagnosis of LPP is made based on histopathological examination, although it is not always definite. The current study evaluates the effectiveness of non-invasive atomic force microscopy (AFM) hair examination in detecting morphological differences between healthy and diseased hair. MATERIALS AND METHODS: Here, three to five hairs from lesional skin of 10 LPP patients were collected and examined at nine locations using AFM. At least four images were taken at each of the nine sites. Metric measurements were taken and metric (length, width, and scale step height) and morphological features (striated and smooth surface of scales, the presence of endocuticle and cortex, shape of scales edges, scratches, pitting, cracks, globules, and wavy edge) were compared with hair from healthy controls. In addition, areas on diseased hair where the process of pathological, unnatural delamination of the hair fiber occurs are described. RESULTS: There was a statistically significant difference in the number of scratches in the initial sections of the LPP hair, in the intensity of wavy edges along the entire length of the tested hair, and in the number of scales with pitting in the middle section of the hair. In addition, a statistically significant higher number of scales with striated surface was found in LPP group starting at 3.5 cm from the root continuing towards the free end of the hair. Other morphological changes such as presence of cortex, globules, oval indentations, and rod-like macrofibrillar elements were also assessed, however, detailed results are not presented, as the differences shown in the number of these morphological changes were not significantly different. CONCLUSION: This publication outlines the differences between virgin, healthy Caucasian hair, and the hair of LPP patients. The results of this study can be used for further research and work related to LPP. This is the first attempt to characterize the hair of LPP patients using AFM.

On-Demand Vaccine Production via Dock-and-Display of Biotinylated Antigens on Bacterial Extracellular Vesicles.

Engineered outer membrane vesicles (OMVs) derived from Gram-negative bacteria are a promising vaccine technology for developing immunity against diverse pathogens. However, antigen display on OMVs can be challenging to control and highly variable due to bottlenecks in protein expression and localization to the bacterial host cell's outer membrane, especially for bulky and complex antigens. Here, we describe methods related to a universal vaccine technology called AvidVax (avidin-based vaccine antigen crosslinking) for rapid and simplified assembly of antigens on the exterior of OMVs during vaccine development. The AvidVax platform involves remodeling the OMV surface with multiple copies of a synthetic antigen-binding protein (SNAP), which is an engineered fusion protein comprised of an outer membrane scaffold protein linked to a biotin-binding protein. The resulting SNAPs enable efficient decoration of OMVs with a molecularly diverse array of biotinylated subunit antigens, including globular and membrane proteins, glycans and glycoconjugates, haptens, lipids, nucleic acids, and short peptides. We detail the key steps in the AvidVax vaccine production pipeline including preparation and isolation of SNAP-OMVs, biotinylation and enrichment of vaccine antigens, and formulation and characterization of antigen-loaded SNAP-OMVs.

Emotion regulation flexibility: EEG/EMG predictors and consequences of switching between reappraisal and distraction strategies.

Flexible use of emotion regulation (ER) strategies is central to mental health. To advance our understanding of what drives adaptive strategy-switching decisions, in this preregistered study, we used event-related potentials (late positive potential, LPP and stimulus preceding negativity, SPN) and facial electromyography (EMG corrugator activity) to test the antecedents and consequences of switching to an alternative ER strategy. Participants (N = 63, Mage = 24.8 years, all female) passively watched and then implemented an instructed ER strategy (reappraisal or distraction) in response to high-intensity negative pictures that were either easy or difficult to reinterpret (high or low reappraisal affordance, respectively). Next, they decided to "switch from" or "maintain" the instructed strategy and subsequently implemented the chosen strategy. Reappraisal affordance manipulations successfully induced switching. Regarding antecedents, switching was predicted by the reduced ER efficacy of the current strategy (corrugator, but not LPP). Switching to distraction was additionally predicted by increased responses to the stimulus during passive viewing (corrugator and LPP) and increased anticipatory effort in implementing reappraisal (SPN). Concerning consequences, switching to distraction improved, whereas switching to reappraisal impaired post-choice ER effects (LPP). However, starting with reappraisal was overall more effective than starting with distraction, irrespective of the subsequent decision (corrugator). Our results suggest that switching between ER strategies occurs in accordance with situational demands (stimulus affordances) and is predicted by reduced peripheral physiological ER efficacy. However, only switching to distraction leads to improved regulatory effects. These insights provide neurocognitively grounded starting points for developing interventions targeting ER flexibility.

Association of LPP and ZMIZ1 Gene Polymorphism with Celiac Disease in Subjects from Punjab, Pakistan.

Celiac disease (CD) is a complicated autoimmune disease that is caused by gluten sensitivity. It was commonly believed that CD only affected white Europeans, but recent findings show that it is also prevailing in some other racial groups, like South Asians, Caucasians, Africans, and Arabs. Genetics plays a profound role in increasing the risk of developing CD. Genetic Variations in non-HLA genes such as LPP, ZMIZ1, CCR3, and many more influence the risk of CD in various populations. This study aimed to explore the association between LPP rs1464510 and ZMIZ1 rs1250552 and CD in the Punjabi Pakistani population. For this, a total of 70 human subjects were selected and divided into healthy controls and patients. Genotyping was performed using an in-house-developed tetra-amplification refractory mutation system polymerase chain reaction. Statistical analysis revealed a significant association between LPP rs1464510 (χ2 = 4.421, p = 0.035) and ZMIZ1 rs1250552 (χ2 = 3.867, p = 0.049) and CD. Multinomial regression analysis showed that LPP rs1464510 A allele reduces the risk of CD by ~52% (OR 0.48, CI: 0.24-0.96, 0.037), while C allele-carrying subjects are at ~2.6 fold increased risk of CD (OR 3.65, CI: 1.25-10.63, 0.017). Similarly, the ZMIZ1 rs1250552 AG genotype significantly reduces the risk of CD by 73% (OR 0.26, CI: 0.077-0.867, p = 0.028). In summary, Genetic Variations in the LPP and ZMIZ1 genes influence the risk of CD in Punjabi Pakistani subjects. LPP rs1464510 A allele and ZMIZ1 AG genotype play a protective role and reduce the risk of CD.

Electrophysiological Correlates of Amplified Emotion-Related Cognitive Processing Evoked by Self-Administered Disgust Images.

In the processing of emotions, the brain prepares and reacts in distinctive manners depending upon the negative or positive nuance of the emotion elicitors. Previous investigations showed that negative elicitors generally evoke more intense neural activities than positive and neutral ones, as reflected in the augmented amplitude of all sub-components of the event-related potentials (ERP) late posterior positivity (LPP) complex, while less is known about the emotion of disgust. The present study aimed to examine whether the LPP complex during the processing of disgust stimuli showed greater amplitude than other emotion elicitors with negative or positive valences, thus confirming it as a neural marker of disgust-related negativity bias at earlier or later stages. Thus, in the present study, we leveraged the ERP technique during the execution of an affective self-administered visual stimuli task to disentangle the neural contributions associated with images of positive, negative, disgust, or neutral emotions. Crucially, we showed that handling with disgust elicitors prompted the greatest neural activity and the highest delay during self-administration. Overall, we demonstrated progressive neural activities associated with the unpleasantness of the emotion elicitors and peculiar processing for disgust compared with all other emotions.

Reduced early neural processing of faces in children and adolescents with social anxiety disorder.

Social anxiety disorder (SAD) is one of the most common mental disorders during childhood and adolescence. Yet, little is known about its maintenance in youth. Cognitive models of SAD indicate that attentional biases play a key role in the dysfunctional processing of social information, such as emotional faces. However, previous research investigating neural correlates of childhood SAD has produced inconsistent findings. The current study aims to investigate neural face processing in children and adolescents with SAD, while taking into consideration methodological limitations of previous studies. We measured event-related potentials (P100, N170, EPN, LPP) in response to happy, neutral, and angry adult faces, and non-social household objects, in a sample of youth (aged 10-15 years) with SAD (n = 57), clinical controls with specific phobias (SP; n = 41), and healthy controls (HC; n = 61). Participants completed an emotion/object identification task while continuous EEG was recorded. Analyses revealed lower N170 amplitudes in the SAD group compared to HCs, irrespective of emotion. In addition, younger children (aged 10-12 years) with SAD showed lower EPN amplitudes and higher early LPP amplitudes (only trend level) in response to neutral and happy faces compared to younger HCs. These effects were specific to faces and were not evident in the neural processing of non-social household objects. Overall, the findings indicate that different neural response patterns are already present in youth with SAD. Group differences, particularly in younger children, suggest age-related differences in neural face processing in childhood SAD and underpin the necessity of developmental approaches.

Intestinal lysozyme engagement of Salmonella Typhimurium stimulates the release of barrier-impairing InvE and Lpp1.

Lysozyme is a ß-1,4-glycosidase that hydrolyzes the polysaccharide backbone of bacterial cell walls. With an additional bactericidal function mediated by a separate protein domain, lysozyme is considered a uniquely important antimicrobial molecule contributing to the host's innate immune response to infection. Elevated lysozyme production is found in various inflammatory conditions while patients with genetic risks for inflammatory bowel diseases demonstrate abnormal lysozyme expression, granule packaging, and secretion in Paneth cells. However, it remains unclear how a gain- or loss-of-function in host lysozyme may impact the host inflammatory responses to pathogenic infection. We challenged Lyz1-/- and ectopic Lyz1-expressing (Villin-Lyz1TG) mice with S. Typhimurium and then comprehensively assessed the inflammatory disease progression. We conducted proteomics analysis to identify molecules derived from human lysozyme-mediated processing of live Salmonella. We examined the barrier-impairing effects of these identified molecules in human intestinal epithelial cell monolayer and enteroids. Lyz1-/- mice are protected from infection in terms of morbidity, mortality, and barrier integrity, whereas Villin-Lyz1TG mice demonstrate exacerbated infection and inflammation. The growth and invasion of Salmonella in vitro are not affected by human or chicken lysozyme, whereas lysozyme encountering of live Salmonella stimulates the release of barrier-disrupting factors, InvE-sipC and Lpp1, which directly or indirectly impair the tight junctions. The direct engagement of host intestinal lysozyme with an enteric pathogen such as Salmonella promotes the release of virulence factors that are barrier-impairing and pro-inflammatory. Controlling lysozyme function may help alleviate the inflammatory progression.

Interplay between sexual excitation and inhibition: impact on sexual function and neural correlates of erotic stimulus processing in women.

Background: As outlined by the dual control model (DCM), individual differences in the regulation of sexual arousal following sexual stimulation depend on two distinct neurophysiological processes: sexual excitation (SE) and sexual inhibition (SI). Although associations with sexual function, behavior, and cue processing have been demonstrated in previous research, underlying neural correlates remain insufficiently explored. Moreover, interactive effects of SE/SI as proposed by the DCM, as well as factors impacting SE/SI properties, such as the use of oral contraceptives (OCs), have not received adequate attention in existing research. Methods: 90 healthy, sexually active women (n = 51 using OCs, n = 39 naturally cycling) completed an Emotional-Picture-Stroop-Paradigm (EPSP) while a 64-channel EEG was recorded. LPP amplitudes toward erotic and neutral stimuli were consecutively computed as a marker of motivational salience and approach motivation. Additionally, women provided self-reports of SE/SI and sexual function. Moderation analyses were performed to assess interactive effects of SE/SI in predicting LPP amplitudes and sexual function. Results: Sexual function was negatively associated with SI levels but unrelated to SE. Higher SI was associated with reduced LPP amplitudes in response to erotic stimuli. This negative association was, however, attenuated for women high in SE, suggesting interactive effects of SE/SI. Furthermore, women using OCs reported lower SE compared to naturally cycling women. Conclusion: The observed findings provide additional psychophysiological evidence supporting the DCM and underscore the relevance of interactive SE/SI effects in stimulus processing and approach motivation. They also highlight the possible impact of OCs on psychosexual variables that warrants further research.

Savoring mental imagery: Electrocortical effects and association with depression.

The ability to focus on and increase positive emotion in response to mental imagery may play a key role in emotional wellbeing. Moreover, deficits in this ability might underlie emotional disorders such as depression. Here, we set out to determine whether people could use savoring to upregulate subjective and electrocortical response to mental imagery of previously viewed positive and neutral pictures, and whether this would be negatively affected by depression. On each trial, participants (N = 49) viewed a positive or neutral picture, prior to simply re-imagining the previously presented picture ("view") or re-imagining the picture while savoring it ("savor"). Results showed that savoring increased electrocortical and subjective response to imagined stimuli; however, this effect was only evident at the electrocortical level when controlling for depression. Moreover, depression moderated electrocortical findings, such that individuals who were more depressed showed a reduced effect of savoring on neural response to mental imagery. Results are in line with recent work that has shown the benefits of positive affect treatment for depression, to suggest that deficits in savoring mental imagery may play a role in the development and/or maintenance of depression.

In vitro digestion properties of Laiyang pear residue polysaccharides and it counteracts DSS-induced gut injury in mice via modulating gut inflammation, gut microbiota and intestinal barrier.

The aim of this study was to explore the dynamic changes in the physicochemical properties of Laiyang pear residue polysaccharide (LPP) during in vitro digestion, as well as its protective effect on the intestines. Monosaccharide composition and molecular weight analysis showed that there was no significant change in LPP during the oral digestion stage. However, during the gastric and intestinal digestion stages, the glycosidic bonds of LPP were broken, leading to the dissociation of large molecular aggregates and a significant increase in reducing sugar content (CR) accompanied by a decrease in molecular weight. In addition, LPP exerted the intestinal protective ability via inhibiting gut inflammation, improving intestinal barrier, and regulating intestinal flora in DSS-induced mice. Specifically, LPP mitigated DSS-induced intestinal pathological damage of mice via enhancing intestinal barrier integrity and upregulating expressions of TJ proteins, and suppressed inflammation by inhibiting NF-κB signaling axis. Furthermore, LPP decreased the ratio of Firmicutes/Bacteroidetes, increased the relative abundance of Lactobacillus, and altered the diversity and the composition of gut microbiota in DSS-induced mice. Therefore, LPP had the potential to be a functional food that improved gut microbiota environment to enhance health and prevent diseases, such as a prebiotic.