Neighbourhood socio‐economic environment (SEE) is associated with obesity in older children and adults, but little is known about this relationship in younger children. Breastfeeding is an important preventative of adiposity in childhood, but its relationship with neighbourhood SEE is unknown.We assessed differences in adiposity and obesity in children before age two by neighbourhood SEE, controlling for family socio‐demographics and breastfeeding duration.z scores (BMIz), and breastfeeding duration were collected at periodic study visits from participants in PREVAIL (n = 245), a birth cohort in Cincinnati, OH. Addresses were assigned a Deprivation Index score, a validated measure of SEE, and dichotomized into highest SEE (least deprived quartile of scores) and not highest SEE (remaining quartiles). Longitudinal and Poisson models assessed differences in BMIz by SEE over the second year of life and obesity risk at age two, respectively , while attenuation of obesity risk by breastfeeding duration was tested in mediation models.Family socio‐demographics, child body mass index z of 0.04  per month of life and increased obesity risk at age two , controlling for family socio‐demographics. Breastfeeding duration attenuated >9% of the obesity risk attributable to SEE .Residing outside of the highest SEE neighbourhoods was associated with an increased BMIz and obesity risk in children before age two, a relationship that was partially mediated by breastfeeding duration.In the PREVAIL Cohort, residing outside of the highest SEE neighbourhoods predicted a significant increase in BMIBreastfeeding support may play an important role in reducing obesity rates in children in lower SEE neighbourhoods. This project seeks to address this knowledge gap using a validated measure of neighbourhood SEE and family‐level factors as predictors of adiposity and obesity, including how breastfeeding behaviours affect these relationships, in a well‐characterized birth cohort. Identifying neighbourhood SEE as a predictor of early obesity could provide public health practitioners with a simple metric for focusing services and interventions in neighbourhoods with the greatest concentration of risk, potentially reducing health disparities through the lifespan.2This project is a secondary analysis using data from the Pediatric Respiratory and Enteric Virus Acquisition and Immunogenesis Longitudinal Cohort (PREVAIL), a prospective two‐year birth cohort study in Cincinnati, OH funded by the U.S. Centers for Disease Control and Prevention (CDC). PREVAIL was approved by the Institutional Review Boards at the CDC and Cincinnati Children's Hospital Medical Center. Recruitment, enrollment, and study methods have previously been describedFor this study, we focused on SEE, defined as aggregate socio‐economic indicators of an environment or neighbourhood, such as average income, education, or house value. Family residential address was reported at the baseline visit and updated, if changed, in REDCap data management software.The Deprivation Index is a validated measure of SEE using six American Community SurveyQuartiles of Deprivation Index score were calculated from assigned scores at all time‐points. Census tracts were categorized by quartile of score into highest SEE (least deprived quartile), high‐mid SEE and low‐mid SEE (intermediate quartiles), lowest SEE (most deprived quartile) and a binary measure of the least deprived quartile (highest SEE) compared to the remaining cohort (not highest SEE). For all comparisons, the Deprivation Index category that corresponded with the measurement timing was used.Family‐level subject data were collected in‐person at baseline (third trimester) and at in‐clinic visits . Maternal race was categorized as White, Black, or other . Maternal age was calculated based on the mother's age at the time of the child's birth. Maternal education level was dichotomized, with levels corresponding to completion of any post‐secondary education or training (>HS) or less (≤HS). Marital status was defined as married or not, regardless of cohabitation status. Insurance status was classified as public or private. There were a few uninsured participants and those who indicated use of both public and private insurance; these were classified as publicly insured. Family income level was categorized in line with the Federal Poverty Level for a family of four (<$25 000/year), between 100% and 200% of Federal Poverty Level ($25 000–$50 000/year) and above (>$50 000/year).z scores (BMIz) from each study visit were calculated using the parameters provided by the CDC National Center for Health Statistics and the LMS method outlined by Flegal et al.,z score from the two proximal visits. Sensitivity analysis found no significant differences in outcomes after removing these imputations. Obesity was defined as a BMIz score at or above the 95th percentile (BMIz ≥ 1.65) at age two per CDC obesity criteria.Body mass index Breastfeeding duration and exclusivity  were self‐reported by the mother on quarterly study questionnaires. Duration of any breastfeeding was calculated in weeks from birth to the maternal reported date of breastfeeding cessation, censored at age two. Duration of exclusive breastfeeding was calculated in weeks from birth until the mother's reported date of the first formula introduction, censored at 6 months of age.2.1Power for each outcome, calculated post‐hoc, was based on the smallest sample size at each study visit for any outcome. Our study had at least 80% power to detect an effect size of ≥30% using any of our analytic methods.r ≥ 0.70) were considered collinear, and not considered for inclusion in multivariable models. Family‐level variables that met non‐collinearity criteria were used in all subsequent models unless otherwise indicated.To characterize the study population, family‐level socio‐demographics by categorical and binary SEE were compared using Fisher's exact test. Spearman correlations between categories of SEE  and each family‐level characteristic were calculated. Variables with a strong correlation  with an exchangeable correlation matrix was constructed using BMIz ≥ 3, with BMIz calculated using WHO LMS criteria. Comparisons of obesity prevalence as calculated by these methods were made using Fisher's exact test. As this analysis includes an American study population, all assessments of obesity risk were made using CDC standards. Relative risk of obesity at age two was calculated using Poisson regression in univariable and multivariable analysis, using the same variable selection approach previously described.Obesity prevalence at age two was calculated and compared using the CDC, IOTF,a). RMST models provide reliable, interpretable estimates of multivariable survival data by comparing estimated mean time to events calculated using areas under the Kaplan Meier survival curves.a results by constructing a series of Poisson regression models controlling for family‐level predictors: (model b) obesity status by the duration of any and exclusive breastfeeding; (model c) obesity status by SEE (model c’) obesity status by SEE and any or exclusive breastfeeding duration. Results were reported as the resulting relative risks and the percent effect mediated (PEM), calculated as the proportion of the effect of SEE attributable to breastfeeding duration (RR model c’/RR model c). Full mediation was defined as a change in significance level of the SEE variable with a concurrent significant effect of breastfeeding in model c’. Partial mediation was defined as a change in the effect size of SEE with a concurrent significant effect of breastfeeding in model c’.As lack of breastfeeding, particularly exclusive breastfeeding, has been associated with risk of obesity,z were calculated using parameters associated with the child's age in months, and GEE models added child's age in months at the time of measurement as an interaction term. However, as differences associated with SEE appeared to increase over time, sensitivity analysis was performed by excluding this subset of subjects from analysis and re‐running the linear regression models of BMIz, logistic models of obesity, and mediation models at age two. As no differences were found after these removals, results are reported using all subjects available at the specific study time‐point.The final quarter of PREVAIL data collection and follow‐up occurred in spring and summer of 2020, which coincided with the early months of the COVID‐19 pandemic. COVID‐19 restrictions resulted in a temporary closure of the study clinic and caused approximately 9% (16/171) of subjects to complete their 24‐month visit outside of the protocol‐established window (within 12 weeks of the child's second birthday). All measures of BMIAll comparisons were made with the highest SEE census tracts as the reference group. Results are reported as estimate and 95% confidence interval (95% CI), except where indicated. Analysis was performed using the R Environment for Statistical Computing version 4.1.2, including the geepack and survRM2 packages.3n = 245) were eligible for inclusion in this analysis. The cohort was racially and economically diverse  and Black race the strongest  correlation. However, use of public insurance was strongly correlated to lower income  and unmarried status , so was excluded from all multivariable models. No other family‐level predictor was strongly correlated (r ≥ 0.70) to either SEE or other family‐level variables, so all multivariable models were adjusted by the covariates race, maternal education, family income, maternal age, and marital status (family‐level predictors) unless otherwise indicated.Correlation coefficients between category of SEE and family‐level predictors were significant but only weakly to moderately correlated, with maternal age the weakest  points higher than those in the highest SEE tracts and 0.60  points higher at 24 months. Pairwise comparisons revealed that the differences were between the highest SEE and the two intermediate categories, with no significant difference between highest and lowest SEE or lowest and either of the intermediate SEE census tract categories at 18 or 24 months. No other ecological or family‐level predictor was associated with significant differences in mean BMIz at any time‐point (data not shown).No measure of SEE was significantly associated with BMIz beginning at 18 months. This relationship was particularly strong at 24 months, with residence in any census tract outside of the highest SEE predicting a significant increase in BMIz of 0.60 points . There were no significant differences among intermediate and lowest SEE census tracts, and the significant family‐level predictors in univariable analysis, Black race and income < $25 000/year, were associated with a decreased BMIz only at 12 months.The low number of participants who identified as ‘other’ race caused a failure in model convergence in several multivariable regression models, thus; race was dichotomized to Black and Not Black for all modelling purposes. In the time‐point specific univariable regression models Table , residenz, while only the effect of SEE remained significant at 24 months. No other family‐level predictor was significantly associated with BMIz in multivariable modelling at any time‐point.Due to the similarity in estimates for all SEE categories outside of highest SEE, the multivariable regression model was constructed using binary highest SEE vs not highest SEE Table . At montz of approximately 0.04 points for each month in child age in both univariable and multivariable models, translating to a difference of 0.44–0.88 points in BMIz for these children from 12–24 months of age. No family‐level predictor was significantly associated with differences in BMIz when generalized from 12–24 months of age.A total of 208 children completed at least one study visit at 12, 18, or 24 months of age, providing 569 observations for GEE models (Table p < 0.001) and WHO  definitions. Using only the CDC definitions, we found significant differences when comparing the highest to not highest SEE census tracts  of the remaining cohort had obesity. In univariable Poisson regression, residing outside of the highest SEE census tracts was associated with a 3.4‐fold increase in risk of obesity compared to the highest SEE census tracts. When controlling for family‐level predictors, the risk for obesity in the not highest SEE tracts was 3.7‐fold that of those in the highest SEE tracts. There were no significant differences in obesity risk associated with family‐level predictors in either the univariable or the multivariable obesity models.Internationally, standards for obesity differ from the CDC standards used in the U.S. Using the CDC obesity standard, prevalence of obesity in PREVAIL children at age two was 15.8% (27/171), significantly higher than the prevalence based on IOTF  was not statistically significant when controlling for family‐level predictors. However, both categorical and binary SEE was significantly associated with differences in any breastfeeding duration; ΔRMST was not significant between highest SEE and high mid, but ΔRMST was significant between highest SEE and low mid  and highest and lowest SEE  when controlling for family‐level predictors. In the binary SEE model, ΔRMST was 4.13 weeks  between highest and not highest SEE. Given the significant relationship between binary SEE and breastfeeding duration, and the significant risk of obesity associated with residing outside of the highest SEE census tracts, mediation was undertaken using the binary SEE measure and duration of any breastfeeding.The RR of obesity for not highest compared to highest SEE census tracts was partially mediated by breastfeeding duration Figure . The imp4z at 18 and 24 months and increased obesity risk at 24 months. Residence outside of the highest SEE neighbourhoods was associated with an increase of BMIz score at 18 and 24 months of age and more than triple the risk of obesity at age two. Examined longitudinally, the differences in BMIz by SEE increased incrementally with each month of child age during the second year of life. Differences in BMIz and obesity did not have a linear dose–response relationship with level of neighbourhood deprivation. Instead, BMIz and obesity were similarly elevated for all groups outside of the highest SEE census tracts. There were few significant associations between family‐level predictors and BMIz in univariable and multivariable analyses, and none in any models of obesity risk; controlling for family‐level predictors did not significantly change the association between neighbourhood SEE and adiposity or obesity in any models. While breastfeeding duration did not fully mediate SEE's effect on obesity risk, it does provide a potential pathway for improving obesity rates, decreasing risk of obesity by nearly 2% for every week of breastfeeding continued.In the PREVAIL Cohort, neighbourhood SEE, as measured by the category of Deprivation Index score, was a significant predictor of increased BMIWhile this study was novel in comparing adiposity and obesity in children under two by neighbourhood deprivation, finding lower obesity in the most affluent group compared to all others is consistent with nationally representative data.This may be due to the combined effects of family socio‐demographics and neighbourhood SEE. Neighbourhood deprivation was significantly, but only moderately, correlated with family‐level sociodemographic differences across all categories and our multivariable models met non‐multicollinearity criteria. However, the highest SEE group had significantly lower proportion of low income, Black, and single‐parent families as well as significantly higher education levels compared to low mid and lowest SEE as well as compared to all others, suggesting a high level of socio‐demographic segregation by neighbourhood at either end of the affluence spectrum.American Apartheid, Massey and Denton quantified how federal policies segregated Black Americans into increasing impoverished urban centers, resulting in generational cycles of concentrated poverty.Socio‐demographic segregation in the U.S. has previously been associated with neighbourhood deprivation and health disparities. In their seminal 1993 publication, The finding that breastfeeding duration at least partially mediated the effects of SEE on obesity risk is important, as the downstream effects of increasing breastfeeding duration extend beyond obesity prevention. Increased breastfeeding duration is linked to a wide array of health benefits, including increased post‐partum weight loss and reduced risk of reproductive cancers for the mother and decreased risk of acute and chronic diseases and improved cognitive development in the infant.Our analysis has some limitations. Our study focused on the predictive power of SEE regarding adiposity and obesity, as well as the influence of breastfeeding on obesity risk, ideally for use as a tool to identify loci and methods for health promotion. Thus, we did not test for interaction between SEE and the family‐level predictors, which may provide more insight into causality. Furthermore, physical environment and domestic stressors, such as neighbourhood crime, financial hardship and food security have been significantly associated with increased risk of obesity in older children.As a secondary analysis of PREVAIL, which aimed to characterize the natural history of respiratory and enteric viral illness in young children, potentially important variables for understanding differences in breastfeeding behaviours, such as timing of maternal return‐to‐work, availability of lactation support, or employment type, were not available and not included in any of the breastfeeding models. As this and other research shows that improving breastfeeding duration may reduce risk of obesity, studies to identify barriers to breastfeeding in these populations are needed to strategize best practices for improving these outcomes.Finally, while PREVAIL's final enrollment was representative of the birth hospitals from which we recruited,5Our approach showed that increased early childhood adiposity and obesity risk are associated with residing outside of the most affluent neighbourhoods as measured by level of material neighbourhood deprivation. We identified shorter breastfeeding durations outside of the highest SEE neighbourhoods as a partial mediator for obesity disparities. Our findings suggest that focusing breastfeeding support and promotion in the highest deprivation neighbourhoods may be an important first step to mitigate early childhood obesity and reduce significant health disparities in at‐risk populations, both in childhood and later in life.The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.


The human prefrontal cortex contains two prominent areas, the frontal eye field and the inferior frontal junction, that are crucially involved in the orchestrating functions of attention, working memory and cognitive control. Motivated by comparative evidence in non‐human primates, we review the human neuroimaging literature, suggesting that the functions of these regions can be clearly dissociated. We found remarkable differences in how these regions relate to sensory domains and visual topography, top‐down and bottom‐up spatial attention, spatial versus non‐spatial  attention and working memory and, finally, the multiple‐demand system. Functional magnetic resonance imaging (fMRI) studies using multivariate pattern analysis reveal the selectivity of the frontal eye field and inferior frontal junction to spatial and non‐spatial information, respectively. The analysis of functional and effective connectivity provides evidence of the modulation of the activity in downstream visual areas from the frontal eye field and inferior frontal junction and sheds light on their reciprocal influences. We therefore suggest that future studies should aim at disentangling more explicitly the role of these regions in the control of spatial and non‐spatial selection. We propose that the analysis of the structural and functional connectivity  of the frontal eye field and inferior frontal junction may be used to further characterize their involvement in a spatial (‘where’) and a non‐spatial (‘what’) network, respectively, highlighting segregated brain networks that allow biasing visual selection and working memory performance to support goal‐driven behaviour. Paradigms that involve spatial mechanisms (red outline) consistently engage the frontal eye field. In contrast, paradigms designed to disentangle non‐spatial  mechanisms from spatial ones (blue outline) predominantly engage the inferior frontal junction. We examine how systematic differences in the structure, function and connectivity fingerprints of these regions underlie this crucial dissociation across attention, working memory and cognitive control functions. ALEactivation likelihood estimationBABrodmann areaBOLDblood oxygen level dependentcTBScontinuous theta burst stimulationDANdorsal attention networkdMRIdiffusion magnetic resonance imagingEEGelectroencephalographyFEFfrontal eye fieldFFAfusiform face areafMRIfunctional magnetic resonance imagingiFEFinferior frontal eye fieldIFGinferior frontal gyrusIFJinferior frontal junctionIFJaanterior inferior frontal junctionIFJpposterior inferior frontal junctionIFSinferior frontal sulcusiPCSinferior precentral sulcusIPSintraparietal sulcusMACMmeta‐analytic connectivity modellingMEGmagnetoencephalographyMFGmiddle frontal gyrusMMP1multimodal parcellation 1.0MVPAmultivariate pattern analysisPCSprecentral sulcusPETpositron emission tomographyPFCprefrontal cortexplPFCposterior lateral prefrontal cortexPPAparahippocampal place areaROIregion of interestRSVPRapid Serial Visual PresentationRTreaction timeSFSsuperior frontal sulcusSLFsuperior longitudinal fasciculussPCSsuperior precentral sulcusSPLsuperior parietal lobuleTMStranscranial magnetic stimulationTPJtemporoparietal junctionVANventral attention networkvlPFCventrolateral prefrontal cortex1It is remarkable to what extent primates have evolved the cognitive faculties that allow their behaviour to be guided not only by their immediate surroundings and environment but also by their future goals and action plans Fuster, . The sucThe prefrontal cortex (PFC) has long been recognized to be crucially involved in many aspects of such complex, organized behaviour in non‐human and human primates  and the inferior frontal junction (IFJ). We would therefore like to stress that the goal of this paper is not to provide a systematic review of FEF and IFJ per se, as these are already available elsewhere  define the concept of a cortical region, along with topographic  organization  movements of the head and eyes and dilatation of the pupils’ Ferrier, . Thus, tMoreover, research has started to identify structural and functional correspondences between the ventrolateral PFC (vlPFC) in macaques and humans, enabling insightful cross‐species comparisons Figure , 2020. I22.1Traditionally, cytoarchitecture has been the most prominent property used in defining cortical maps , part of BA6 , and IFJ as a dysgranular region lying in the posterior bank of the IFS, in BA6, BA8 and BA44. However, due to the very limited sample available in post‐mortem studies, the question that is crucially left open is whether these results can be generalized to the localization (and the borders) of FEF and IFJ as defined by non‐invasive methods (primarily fMRI) in larger cohorts. Conversely, it is left open whether evidence derived from probabilistic structural atlases , the former in the vicinity of its intersection with the superior frontal sulcus (SFS), and the latter ventrally, in the vicinity of its intersection with the IFS  areas, we reviewed here novel evidence that favours a more general involvement of the FEF in spatial tasks, as only FEF contains a precise topographic representation of contralateral space, whereas the IFJ  has only quite limited overlap with topographically organized areas  on the brain regions and networks subserving visual attention was dedicated to understanding how the brain achieves top‐down control over visual input or, conversely, how attention is automatically driven by bottom‐up factors  evidence that helps to reveal the contribution of the FEF and IFJ to attentional control and working memory processes, thus complementing the correlational studies described earlier with causal evidence. In Ruff et al. , the autThe TMS evidence on the IFJ is much scanter, but nevertheless essential to understand its role in top‐down control. The influential study by Zanto et al.  used a n3.3Functionally, it is very well possible to dissociate the behavioural effects and the neural mechanisms of spatial versus feature‐ and object‐based  attention  visual selection  is crucial. As we have seen, disentangling non‐spatial processes at the behavioural level requires sophisticated experimental techniques and designs that render spatial information irrelevant during the execution of the task. Furthermore, studying object‐based control processes requires also ruling out the possibility that the participants could rely on low‐level features to perform the task. In this sense, the study by Liu  was desiCritically, even though all the regions reported in most of the previous studies  are implicated in top‐down modulation, measuring the temporal profile of their involvement in spatial and non‐spatial processes is crucial to firmly establish which are the sources of the modulation within the attention networks. In contrast to fMRI, MEG is ideally suited to measure neural activity with a high temporal resolution and to reveal the statistical interdependence of signals originating from different cortical sources  that the former is predominantly involved in processing spatial information, whereas the latter is predominantly involved in processing non‐spatial information. Moreover, functional and effective connectivity metrics revealed that the coordination of spatial and non‐spatial selection requires the communication between the FEF and IFJ and posterior areas, in which the FEF assumes the role of a spatial ‘priority map’, whereas the IFJ biases non‐spatial visual processing and acts more as a control structure that allocates attentional resources depending on the task at hand in a flexible way. An interesting question to address seems therefore whether the role of the IFJ in cognition is more multifaceted than the role of the FEF, which could be thought of as more specialized. This would seem reasonable from a comparative perspective because the PFC and the information processing stream in which the IFJ is hypothesized to be embedded  are fMRI studies that identified overlap in frontal and parietal regions between the activity elicited by a wide range of tasks and resting‐state functional connectivity patterns Duncan, . TraditiIn the study by Muhle‐Karbe et al. , the autn = 449 subjects from the Human Connectome Project; Van Essen et al., n‐back task, a relational reasoning task and a math/story task), the authors identified areas that formed part of the ‘penumbra’ and the ‘core’ multiple‐demand system by computing the parcels that had stronger mean activations compared with the initial 27 parcels of the ‘extended’ multiple‐demand system. Interestingly, both the area IFJp  and the area i6‐8  that lies immediately anterior to the FEF were included in the core multiple‐demand system. An additional analysis using contrasts with weaker cognitive demands in the working memory and relational reasoning tasks identified additional foci in the FEF and anterior IFJ (IFJa), among others. This suggests that these regions may display partial multiple‐demand characteristics and that this possibility may need further scrutiny. However, as shown by the analysis of resting‐state functional connectivity, the core regions were more strongly interconnected, and all belonged to the frontoparietal network  by performing the virtual dissection of this bundle  is prevented by the fact that probabilistic tractography results are strongly affected by the location where the streamlines are initialized to propagate. Thus, evidence from the seed‐based analysis of the structural connectivity of the IFJ is needed to complement these findings. Finally, the authors also used a deterministic tractography algorithm to perform a virtual dissection of the white‐matter bundles that connect the PPA and the FFA to the pars opercularis (which includes part of the IFJ) and suggested that the uncinate fasciculus underlays these structural connectivity pathways.Unfortunately, the seed‐based structural connectivity analysis of the IFJ suffers from a remarkable lack of data. Moreover, to the best of our knowledge, no publication reported evidence on the structural connectivity of the functionally defined IFJ. Baldauf and Desimone  analysedn = 129; Figure z scores (thresholded at 50%) of these components differentially loaded on the SLF1 and SLF3 cortical terminations, respectively. The SLF2 terminations instead overlapped with both components , and this bundle was therefore suggested to underlie the interactions between these two functional components. Based on the figures from this study , but the remaining seeds  were defined through a correlation analysis in a second dataset, and finally that the segregation of the networks was tested in a yet third, independent dataset (n = 50 and n = 45). The authors were able to show that a frontoparietal network is interposed between the DAN and the hippocampal‐cortical memory system with minimal overlap. An important refinement of the proposed role of the frontoparietal network was formalized by Cole et al. , the FEF  was reported to be part of the DAN and showed increased functional connectivity with the caudal IPS and SPL, whereas the ventro‐caudal frontal region  all the foci that were co‐activated with the putative IFJ seed, in a way that effectively makes their ROI definition agnostic for anatomical descriptors and functional specialization of this region. Their MACM results (which were drawn from 180 experiments for the left IFJ and 131 for the right IFJ) reveal that the IFJ is robustly co‐activated with the dlPFC and the vlPFC, the MFG/pre‐supplementary motor area, the anterior insula, the posterior parietal cortex and the occipitotemporal junction, among others. The authors interpret these findings as largely consistent with the proposal advanced by Cole and Schneider (https://github.com/ThomasYeoLab/Ngo2019_AuthorTopic) to find subcomponents in the co‐activation patterns of the left IFJ cluster reported in the previous study by Muhle‐Karbe et al.  in both fMRI  and that was pioneered thanks to the comparative studies by Goldman‐Rakic and colleagues  has been recently addressed by employing advanced registration algorithms . However, a limitation of these studies is that they used already established homologies between the macaque and the human brain to identify the target regions and compute the connectivity fingerprints of their seeds in PFC. Furthermore, in the macaque, all these regions (both seeds and targets) were based on cytoarchitectonic definitions  can be considered reasonably accurate and robust in terms of inter‐individual differences in the sulcal organization . While MVPA approaches have generally reported evidence supporting this claim (Jerde et al., n‐back fMRI experiment requiring either the encoding of the abstract identity of an object or its viewpoint and apply MVPA to the FEF and IFJ to see whether the decoding accuracy differs between the two in these tasks. We suggest that because the ‘identity’ task is more independent of low‐level visual features compared with the ‘viewpoint’ task, we should expect a better decoding accuracy within the IFJ compared with the FEF (see the study by Henderson & Serences, Another critical issue for evaluating the current proposal is to determine how exactly this information is coded by these regions at the computational level. In the working memory literature, an influential family of models emphasizes a distinction between regions that encode working memory information from other regions that dynamically exert control over these stored representations, possibly localized in the parietal and frontal cortices (reviewed in Serences, The PFC is generally characterized by a high degree of interconnectedness between its areas and with the rest of the brain—a property that is thought to underlie its unique contribution to complex behaviour Fuster, . This inFinally, we would like to highlight some of the most promising future research directions that would allow dissociating the function of the FEF and IFJ. As we have argued throughout this review, the concept of connectivity fingerprints (Mars, Passingham, & Jbabdi, In contrast, studies on resting‐state fMRI allowed gathering an impressive amount of information about the involvement of the FEF and IFJ in specific brain networks (Ji et al., Top‐down selection and working memory maintenance typically involve a complex chain of neural activity patterns, and this dynamic nature cannot be underestimated. Tracking the temporal profile of this activity at an appropriate timescale is therefore crucial to understand selective visual behaviour (Fiebelkorn & Kastner, Finally, arguably one of the most direct ways to dissociate the contributions of the FEF and IFJ to selective visual behaviour would be to perform a TMS experiment using an endogenous cueing paradigm alternating spatial and feature‐based attention blocks (see question six in Table Visual attention and working memory play a fundamental role in our increasingly cluttered and distracting environments. Understanding the neural mechanisms and the brain networks underlying these functions is crucial for cognitive neuroscience, but it is ultimately also a relevant goal for clinical and industrial applications that could greatly benefit from this basic knowledge. By contrasting the structure, function and connectivity fingerprints of the FEF and IFJ, we have provided some insights into how comparative research and multimodal neuroimaging data can be fruitfully combined to study the organization of the plPFC and to dissociate the function and connectivity fingerprints of the FEF and IFJ as we continue to investigate the neural mechanisms of selective goal‐driven behaviour.The authors report no conflict of interest.MB conceptualized the organization of the review, collected the references, wrote the initial draft and prepared the figures and tables. DB supervised the writing of the manuscript and the preparation of the figures and tables, revised them and suggested additional references. Both authors contributed to the general discussion by proposing avenues for future research. Finally, they both revised and agreed on the final version of the manuscript.https://publons.com/publon/10.1111/ejn.15393.The peer review history for this article is available at


Clinical Case Reports, the authors have updated the content in Acknowledgment section as follows: “All authors would like to include their sincere thanks to Dr. Jihad Nassar, an otolaryngology consultant at King Abdulaziz Medical City—National Guard Hospital in Riyadh, for his help in caring for the patient and his suggestions regarding the manuscript writing.”In the article entitled “Hyaluronic acid augmentation pharyngoplasty complicated by retropharyngeal abscess and Grisel syndrome: Case report and literature review”


Febrile infection–related epilepsy syndrome (FIRES) is a devastating immune inflammatory–mediated epileptic encephalopathy. Herein, we discuss a previously healthy 8‐year‐old boy with FIRES in whom high dosages of conventional and nonconventional anesthetics were ineffective in treating SE, as were ketogenic diet, intravenous corticosteroids, and immunoglobulins. After 29 days of prolonged SRSE, the patient was successfully treated with sevoflurane paired with plasma exchange, for a total of five days, thus obtaining a stable EEG suppression burst pattern with no adverse events. Anakinra at the dosage of 100 mg b.i.d. was started seven days after sevoflurane and plasma exchange had been discontinued and was effective in ensuring non‐recurrence of SE. Sevoflurane as bridge therapy for immunosuppressive treatment could be considered an early, safe, and effective option in treating convulsive SE in which an autoimmune‐inflammatory etiology can reasonably be hypothesized. Sevoflurane such as isoflurane should also be considered in treating refractory convulsive status epilepticus in children.Sevoflurane as bridge therapy for plasma exchange and anakinra in treating convulsive status epilepticus of presumed or ascertained autoimmune‐inflammatory etiology.Lower concentration, a shorter anesthesia induction time and benzodiazepine co‐administration could reduce sevoflurane toxicity and enhance its efficacy.1Febrile infection–related epilepsy syndrome (FIRES), which has now been classified as a subset of new‐onset refractory status epilepticus (NORSE), is a devastating epileptic encephalopathy that typically begins with a mild nonspecific febrile illness in an otherwise healthy individual.Bilateral and multifocal seizure onset with autonomic features and a strong tendency to evolve into bilateral tonic‐clonic seizures is commonly observed. Specific EEG patterns have been recognized in patients with FIRES.Here we report a case of an 8‐year‐old boy with FIRES in whom inhalation anesthesia with sevoflurane as bridge therapy for immunosuppressive treatment with plasma exchange and anakinra was effective and safe in controlling a prolonged SRSE.2An otherwise healthy 8‐year‐old boy with a recent febrile status was transferred to the pediatric iIntensive‐care unit (PICU) of Meyer Children's Hospital from a second‐level hospital due to a coma status and recurrent focal motor seizures. Blood and cerebrospinal fluid exams were unremarkable, and a clear infective etiology was not identified. Previously the patient had been unsuccessfully treated with endorectal diazepam and intravenous benzodiazepines, phenytoin and phenobarbital. Upon admission to our hospital, the patient was intubated and underwent continuous video‐electroencephalography (EEG) monitoring which recorded right and left focal motor seizures and secondarily generalized seizures fulfilling the criteria for refractory SE.The patient was therefore enrolled in a national multicenter randomized sequential trial approved by the Italian Medicines Agency  and randomized to ketamine (KE) (study arm).3In our case, inhaled anesthesia with sevoflurane combined with plasma exchange was effective in controlling a prolonged SRSE with no adverse events. An EEG SB pattern was only achieved with sevoflurane, and SRSE resolution was obtained when plasma exchange therapy was added, thus confirming the efficacy of immunotherapy in FIRES. The low blood solubility and high lipid solubility of sevoflurane are responsible for its rapid distribution in the cerebral tissue and its scarce elimination through plasma exchange, unlike the most commonly used intravenous anesthetics.Isoflurane is the only volatile anesthetic recommended in the treatment of RCSE.Recent experimental studies suggest that volatile anesthetics have a neuroprotective effect when the brain is undergoing ischemia, yet they display neurotoxicity under normal brain conditions when administered during early or late development stages.We report administering sevoflurane for an extremely severe epileptic episode of prolonged SRSE. It was administered along with MDZ and lorazepam. Both the ischemic condition together with the paired administration of benzodiazepines may have contributed to the reduction of its toxicity and may have enhanced its efficacy.In our case, anakinra was efficacious in maintaining seizure control after sevoflurane withdrawal, thus supporting its efficacy in FIRES.The brain MRI revealed a diffuse cortical‐subcortical brain atrophy, as is often reported in FIRES patients.We suggest that sevoflurane as bridge therapy for immunosuppressive treatment could be taken into consideration early in those children with SE in which an autoimmune‐inflammatory etiology may be reasonably hypothesized.The authors have disclosed that they do not have any potential conflicts of interest. The authors confirm that they have read the Journal's position on issues involved in ethical publication and affirm that this report is consistent with those guidelines.


We read with great interest the case report by Fierro et al.  about a Fierro et al. stated themselves they could not definitively rule out anaphylaxis because clinical diagnostic criteria—according to the “Second symposium on the definition and management of anaphylaxis” —could haHowever, relative bradycardia—defined as a severe form in which heart rate falls despite worsening hypotension—has been observed in a randomized controlled trial on venom immunotherapy and anaphylaxis by Brown et al.  They obsKounis first described a syndrome characterized by the association of multiple acute coronary syndromes—including coronary spasm, acute myocardial infarction and stent thrombosis—with mast-cell and platelet activation in the setting of allergic/hypersensitivity reactions and anaphylactic/anaphylactoid insults. Cases are described in patients of any age or medical condition ; clinicaIn a review by Tsur , fifteenIn 2018, the first report  of cardiYanai and Ariyoshi  reportedIn conclusion, we suggest that in this case a diagnosis of Kounis or Kounis-like syndrome could also be strongly taken into account. This work highlights Kounis syndrome’s protean nature and the risk of underestimation, especially in the anesthesia setting, such as in the case described by Fierro et al. Moreover, diagnosis is challenging but essential, especially in case of acute coronary syndrome: even if treatment guidelines are still lacking , timely


Extracellular vesicles (EVs) mediate the cross‐talk between cancer cells and the cells of the surrounding Tumour Microenvironment (TME). Professional killer cells include Natural Killer (NK) cells and CD8+ Cytotoxic T‐lymphocytes (CTLs), which represent some of the most effective immune defense mechanisms against cancer cells. Recent evidence supports the role of EVs released by NK cells and CTLs in killing cancer cells, paving the road to a possible therapeutic role for such EVs. This review article provides the state‐of‐the‐art knowledge on the role of NK‐ and CTL‐derived EVs as anticancer agents, focusing on the different functions of different sub‐types of EVs. We also reviewed the current knowledge on the effects of cancer‐derived EVs on NK cells and CTLs, identifying areas for future investigation in the emerging new field of EV‐mediated immunotherapy of cancer. Among the plethora of cells alerted to intervene, natural killer (NK) and cytotoxic CD8+ T (CTLs) cells are deemed as the ‘professional killers’ because of their involvement in the direct killing of pathogens. These lymphocytic cells share common progenitors and immune functions  cells have been first identified in the 1970s as naturally cytotoxic killer lymphocytes that can kill the target cell without prior exposure to antigens  are CD56dim, whereas CD56bright NK cells (∼5%) reside primarily in the SLTs    including tonsils, spleen and lymph nodes (LNs)  which in turn promote CTL differentiation  class I molecules  are part of the adaptive immune system. Their generation process begins from the hematopoietic stem cells (HSC) residing in the bone marrow. These cells mature into common lymphoid progenitors (CLPs) that migrate to the subcapsular region of the thymus . Exosomes are some of the most studied sub‐types of EVs originally described as ≈50 nm vesicles originating from multivesicular bodies (MVBs)  together with CD4+ T helper (Th) cells constitute the armed division of the adaptive immune response. Generally, they recognize and kill tumour cells by direct cell‐to‐cell contact carrying out the significant task of eliminating the tumour threat as first responders , exosomes generated by the tumour cells displayed high levels of TGF‐β1 that caused sustained phosphorylation and subsequent activation of Smad‐2/3 proteins in NK cells leading to a weakened degranulation and killing ability toward target cells after treatment with ccRCC TEXs  showed significant downregulation of a group of chemokine comprising CXCR4, CCL3, CCL4, and CCL5 involved in cell migration. A marked increase of adenosine production by NK cells was also detected together with reduced migration capacity leading to the conclusion that LEXs exerted a sort of ‘paralyzing’ effect on NK cells acting directly on the cells and, at the same time, forcing them to stop their movements autonomously. Also, NK cells didn't need to necessarily internalize LEXs to be subjected to their effect, a proof of the multiple ways of interaction that LEXs possess to be effective on their target cells  were found to stimulate proliferation and cytotoxic potential when co‐cultured with NK cells. Specifically, OCEXs contained high levels of NF‐kB‐activated kinase‐associated protein 1 (NAP‐1), an important upstream regulator of the interferon regulatory factor 3 (IRF‐3), which activates the expression of the type I interferon (IFN) gene and some chemokine ligand (CXCL) genes  in the cargo or surface of professional killer cells’ derived EVs that affects their ability to kill cancer cells or whether the killing results from a combination of different types of molecules still needs to be established. Secondly, it is unclear how many EVs and how frequently they need to be administered in order to achieve a significant anti‐cancer effect, and how such a schedule of administration can be modified to improve the clinical outcome. Thirdly, is there a sub‐type of EVs which is better than others to achieve a therapeutic goal? Finally, how NK‐ and CTL‐derived EVs can be engineered to further improve their efficacy and how they can be directed specifically to the target cells, preventing or limiting possible side effects? While these questions need to be answered before we can translate the preclinical evidence to the clinics, it remains the fact that EVs from professional killer cells hold several possible advantages over the use of the immune cell themselves for therapeutics: in primis, EVs likely do not undergo the same receptor‐mediated immunoescape mechanisms that immune cells would undergo; moreover, they probably have an easier time to cross anatomical barriers (such as brain blood barrier and testis blood barrier) than immune cells and the preliminary in vivo evidence did not show significant incidence of ‘cytokine storm’—like symptoms in animals treated with NK— and CTL‐derived EVs. We are witnessing the dawn of a fascinating new chapter in cancer biology and therapeutics, in which immune cell‐derived EVs are the main character. The next chapter is to try to address the above questions, in order to determine whether an EV‐based immunotherapy  represents a valuable additional weapon in the war against cancer and will improve the prognosis of cancer patients.The authors do not have any conflicts of interest to declare.


DNA fragmentation produced by apoptotic DNases (endonucleases) leads to irreversible cell death. Although apoptotic DNases are simultaneously induced following toxic/oxidative cell injury and/or failed DNA repair, the study of DNases in apoptosis has generally been reductionist in approach, focusing on individual DNases rather than their possible cooperativity. Coordinated induction of DNases would require a mechanism of communication; however, mutual DNase induction or activation of DNases by enzymatic or non‐enzymatic mechanisms is not currently recognized. The evidence presented in this review suggests apoptotic DNases operate in a network in which members induce each other through the DNA breaks they produce. With DNA breaks being a common communicator among DNases, it would be logical to propose that DNA breaks from other sources such as oxidative DNA damage or actions of DNA repair endonucleases and DNA topoisomerases may also serve as triggers for a cooperative DNase feedback loop leading to elevated DNA fragmentation and subsequent cell death. Therefore, mutual induction of apoptotic DNases has serious implications for studies focused on activation or inhibition of specific DNases as a strategy for therapeutic intervention aimed at modulation of cell death. Follow‐up studies demonstrated that in some models, the induction of different apoptotic DNases occurred at different time‐points after a cell death stimulus. Apoptotic DNA fragmentation induced by the protein kinase inhibitor staurosporine in proliferating N1E‐115 neuroblastoma cells was associated with induction of CAD followed by its disappearance that coincided with the induction of DNase γ.The notion of a cooperative relationship among DNases is reinforced by two recent studies that demonstrated both EndoG and DNase I acting alone can induce each other and several other apoptotic DNases.Mutual induction by directly targeting promoter regions of other DNases is not the only mean by which DNases can cooperate. In terms of sequence specificity, DNases often overlap with each other. However, due to some specificity of the initial cleavage, endonucleases may cooperate with each other in a manner where the product of one may act as the substrate of another. In particular, DNase I was shown to stimulate the ability of human recombinant EndoG to produce double‐stranded DNA breaks in naked DNA and chromatin in vitro.3Celegans homologue of human AP endonuclease FEN‐1 that is normally involved in DNA replication and repair, was reported to cooperate with C elegans Endo G (CPS‐6) in DNA fragmentation, utilizing the endonuclease activity of CPS‐6 and both the 5’‐3’ exonuclease activity and gap‐dependent endonuclease activity of CRN‐1.DNases are just one source of DNA breaks, and it is logical to propose that DNA breaking mechanisms in general, including radiation, mitochondria‐ and drug‐induced reactive oxygen species (ROS), apurinic/apyrimidinic (AP) DNA repair endonucleases and DNA topoisomerases (stopped mid‐reaction by topoisomerase inhibitors), may contribute to apoptotic DNase induction through a feedback loop or act cooperatively with apoptotic DNases Figure . There iWhether initial oxidative DNA breaks, DNA repair endonuclease‐mediated DNA breaks or topoisomerase‐bound DNA breaks directly contribute to the pool of breaks and directly activate or cooperate with apoptotic endonucleases has not been studied. The absence of research on such relationships could be because the interactions are difficult to distinguish and study separately due to lack of appropriate research tools or an apparent lack of interest. However, even in a simple in vitro model, the anticancer drug bleomycin able to directly induce DNA strand breaks, induced transcription of DNase I and EndoG genes inserted in an expression vector as effectively as recombinant endonucleases.4The precise mechanisms that enable apoptotic DNases to act simultaneously during cell death remain unclear. Central questions include how DNases mutually induce each other and how non‐enzymatic mechanisms, such as ROS, radiation or drug‐induced DNA damage, activate DNases. In light of the evidence for an apoptotic DNase network, studies involving DNases need to consider DNases do not act independently from each other. Studies designed to activate a single DNase in an attempt to stimulate cell death (eg targeting cancer cells) or inactivate a particular DNase for the purpose of tissue protection from an injury would require monitoring the activity of other DNases. Perhaps, a better strategy for tissue protection might be simultaneous inhibition of several DNases by broad‐spectrum inhibitors instead of a single highly specific inhibitor.The authors declare no competing financial interests.Alexei G. Basnakian: Conceptualization ; Data curation ; Investigation ; Project administration ; Writing‐original draft ; Writing‐review & editing . Christopher L. Moore: Conceptualization ; Formal analysis ; Writing‐review & editing .


The inflammasome is a cytosolic multiprotein complex that plays a crucial role in inflammation and cell death. The sensor proteins in the inflammasome complex detect various microbial and endogenous stimuli, leading to subsequent caspase activation. The activation of caspases results in the maturation of pro‐inflammatory cytokines IL‐1β and IL‐18 or pyroptosis. Inflammasome dysfunction is associated with the pathogenesis of various diseases, including autoimmune disease and cancer. It appears that the interactions between the gut microbiota and the inflammasome play crucial roles in the gastrointestinal tract. The gut microbiota induces the expression and activation of inflammasome proteins, which contribute to both homeostasis and disease in the gut. Likewise, although controversial, mounting evidence suggests that inflammasome activation can modulate the composition of the gut microbiota, which, in turn, affects disease progression. In this review, we summarize the current concepts and recent insights linking the inflammasome and gut commensal microorganisms. We describe how the reciprocal interaction between the inflammasome and the commensal microbiota relates to physiological and pathophysiological consequences in the host. In this review, N. Kamada and colleagues discuss the effects of the crosstalk between the inflammasome and commensal microorganisms on the physiology and pathophysiology of the host. Antimicrobial peptidesAntimicrobial peptides (AMPs) are synthesized natural antibiotics produced by nearly all organisms, from bacteria and archaea to plants and animals.Commensal bacteria“Commensal” originates from the Latin meaning “sharing the same table”, an alternative term for microbiota. Commensal bacteria are defined as the normal beneficial gut resident bacteria of importance for digestion of food and protecting the gut against pathogenic bacteria.Damage‐associated molecular patterns (DAMPs)Intracellular molecules released from damaged or dying cells that can activate the innate immune system through their interaction with pattern recognition receptors (PRRs.)DysbiosisDysbiosis is the condition that describes an imbalance of beneficial and pathogenic bacteria in the microbiota, and it has a negative impact on the physiology of the host.InflammasomeMultimeric protein complex consists of an inflammasome sensor, the adaptor protein ASC, and cysteine protease caspase‐1. Its primary function is to process pro‐IL‐1β and pro‐IL‐18 into their mature forms and to execute inflammatory cell death termed pyroptosis.Inflammatory bowel disease (IBD)A group of intestinal disorders characterized by chronic inflammation of the bowel. Ulcerative colitis (UC) and Crohn's disease (CD) are the two most common types of IBD.Lipoteichoic acid (LTA)LTA is a cell wall component exclusive to Gram‐positive bacteria and is shed during bacterial replication and after therapeutic administration of antibiotics. LTA is considered an immunostimulatory functional equivalent to lipopolysaccharide (LPS), a major cell wall component of Gram‐negative bacteria.Pathogen‐associated molecular patterns (PAMPs)Conserved molecular structures shared by several pathogens that are recognized by innate immune receptors.PyroptosisA gasdermin D (GSDMD)‐dependent programmed cell death is initiated by caspase‐1 or caspase‐11 activation. It occurs most frequently on infection with intracellular pathogens.Toll‐like receptors (TLRs)Germline‐encoded receptors recognize pathogen‐associated molecular patterns. TLR signals result in the activation of cells and the production of pro‐inflammatory mediators.et al, et al, The term inflammasome was introduced in 2002 to describe an inducible high molecular weight complex containing nucleotide‐binding domain, leucine‐rich repeat containing protein (NLR) family pyrin domain containing 1 (NLRP1), PYCARD (ASC), and caspase‐1. Consistent with the NLRP1 inflammasome, an inflammasome complex usually consists of three components: a sensor component, an adapter molecule, and an effector component. To date, several kinds of inflammasomes have been identified and broadly classified into three groups based on the sensor component: NLR‐associated inflammasomes, absent in melanoma‐2 (AIM2)‐like receptor (ALR)‐associated inflammasomes, and the pyrin inflammasome  littermates   , mitigates DSS‐induced colitis, Salmonella‐induced colitis, and Burkholderia thailandensis‐induced pneumonia  through the activation of NLRC4, which plays a central role in disease tolerance in these models  signaling. LTA also serves as a ligand, binding to NLRP6 to activate the inflammasome via the ASC–caspase‐11–caspase‐1 signaling cascade  in 2002 demonstrated that co‐expression of NLRP6 and ASC in human cell lines results in the activation of caspase‐1 and NF‐κB  and the family Prevotellaceae . In addition to its influence on the mucus layer, IL‐18 may modulate the abundance of A. muciniphila through the induction of antimicrobial peptides (AMPs)  in Aim2−/− mice compared to WT mice, confers the susceptibility to colitis on the host. To determine a mechanism, they focused on the role of IL‐18 in the regulation of IL‐22 signaling. IL‐22 is known to regulate the expression of AMPs in intestinal epithelial cells, including REG3γ and REG3β (McDonald et al, et al, et al, et al, et al, Like other inflammasome proteins, the AIM2 inflammasome has a physiological function to control the gut microbiota Fig  (Hu et aThe genetic mutations in inflammasomes are linked to autoinflammatory disorders. As inflammasomes are a key regulator underlying chronic diseases driven by inflammation that often arise in aging populations living a Western lifestyle, their physiological role has earned more attention among investigators. Although a primary function of inflammasomes is as an elaborate sensor, enabling a host to discriminate beneficial bacteria from malicious bacteria, inflammasomes are also the intermediaries in the cross talk between a host and its intestinal inhabitants. As discussed in this review, the environmental condition of the intestinal lumen is constantly translated into the host response to induce specific signals through IL‐1β or IL‐18 production, which results in a modulation of the intestinal microbiota by IL‐22 and AMPs. In turn, the modulated microbiota may enhance the host response through microbial metabolites, such as short‐chain fatty acids and bile acid derivatives. Thus, inflammasomes are indispensable in their ability to coordinate a precise reciprocal interaction in the body. On the other hand, the commensal microbiota should be regarded as one of the most important factors contributing to IBD pathogenesis. Our review of studies involving inflammasome mutant mice provided evidence that inflammasome activation through exposure to the normal commensal microbiota can exacerbate an intestinal inflammation if the intestinal epithelial integrity is impaired, or if the genetic background of the host contributes some influence. Considering that IBD develops when genetically susceptible individuals with impaired epithelial function are exposed to a trigger, such as the intestinal microbiota, the studies of inflammasome function suggest that inflammasomes recapitulate the actual clinical picture that occurs in IBD patients.Data obtained from mouse models provide valuable insight, increasing the understanding of the association between the inflammasome, intestinal microbiota, and disease. In the field of gastroenterology, accumulated evidence using mouse models elucidates the potential pathogenic link between the inflammasome and IBD. Despite contradictory findings, it is likely that the aberrant activation of the inflammasome worsens IBD pathogenesis. Thus, inhibitors of the inflammasome and its downstream mediators, such as IL‐1β and IL‐18, may be optimal targets for the treatment of IBD. On the other hand, the inhibition of the inflammasome may have no effect or even a negative impact in individuals who lack increased expression of inflammasome‐related pathways. Given the ability of the inflammasome to prevent the expansion of pathobionts, inhibition of the inflammasome may exacerbate disease. Thus, in the clinical setting, the identification of patients who may respond to inflammasome‐targeted therapies may be critical.We do not have concrete evidence of NLRP1 inflammasome function to modulate the intestinal microbiota, nor do we know the clinical impact of the NLRP1 inflammasome on disease.Although a genetic study has identified a SNP associated with ulcerative colitis, it remains unclear what proportion of patients can be associated with the dysregulation of the NLRP3 inflammasome with regard to IBD pathogenesis.Although gain‐of‐function mutations of the NLRC4 gene cause autoinflammation with infantile enterocolitis, the role of the NLRC4 inflammasome in IBD remains uncertain.There is some evidence that refutes the impact of the NLRP6 inflammasome on the intestinal microbiota.Clinical relevance between the AIM2 inflammasome and IBD pathogenesis remains unclear.DW, YG, and NK wrote the manuscript.The authors declare that they have no conflict of interest.


This clinical randomized study aimed to evaluate the early plaque formation on nonresorbable polytetrafluoroethylene (PTFE) membranes having either a dense (d‐PTFE) or an expanded (e‐PTFE) microstructure and exposed to the oral cavity.Twelve individuals were enrolled in this study. In a split‐mouth design, five test membranes (e‐PTFE) with a dual‐layer configuration and five control membranes (d‐PTFE) were bonded on the buccal surfaces of posterior teeth of each subject. All study subjects refrained from toothbrushing during the study period. Specimens were detached from the teeth at 4 and 24 hr and subjected to viability counting, confocal microscopy, and scanning electron microscopy. Plaque samples were harvested from neighboring teeth at baseline, 4, and 24 hr, as control. Wilcoxon signed rank test was applied.Staphylococcus spp. decreased on the tooth surfaces and increased on both membranes overtime, with a significant difference compared to teeth. The total biomass and average biofilm thickness of live and dead cells were significantly greater at the d‐PTFE barriers after 4 hr.No bond failure of the membranes was reported. Between the early and late time points, viable bacterial counts increased on all membranes, with no difference between the test and control. The number of in vivo behavior of different membranes used in guided bone regeneration (GBR).This study demonstrated that the e‐PTFE membrane was associated with a lesser degree of biofilm accumulation during the initial exposure compared to the d‐PTFE membrane. The present experimental setup provides a valuable toolbox to study the  Since then, a large variety of membranes have been introduced  through a clinical examination and an individual case history to identify possible risk factors. All participants were informed about the objectives, methodology, and purpose of the study, and those who agreed to participate were required to provide verbal and written consent prior to entry. This study was reviewed and approved by the Local Ethical Review Board in Gothenburg — Sweden (Dnr 379‐14).2.1Round specimens (4 mm diameter and 0.25 mm thickness) were punched from polytetrafluoroethylene (PTFE) membranes under sterile conditions. Test and control membranes were used. The test membrane was the nonresorbable expanded PTFE (e‐PTFE)  with a dual‐layer configuration, where the layer thickness and the degree and direction of expansion  were optimized to achieve a distinct membrane structure. The control membrane was the commercially available nonresorbable dense polytetrafluoroethylene (d‐PTFE) membrane . Detailed description of the material properties of both membranes can be found at Trobos and coworkers , supragingival plaque samples were harvested with a sterile curette from the buccolingual surfaces of a lower cuspid, which served as control for microbiological analysis in each patient. After that, professional mechanical tooth cleaning was performed with the use of abrasives and rubber cups. The membrane specimens were then fixed on the buccal surfaces of the experimental teeth: premolars and first molars in the upper jaw (six teeth) and second premolars and first molars in the lower jaw (four teeth) Figure . When con = 12) and qualitative (n = 6) analyses . The assignment of test and control membranes on the right or left side of the participants was randomized by lottery in a split‐mouth design according to two experimental protocols that were created to allocate equal number of specimens to the respective quantitative  and brucella agar plates (B350)  and incubated at 37°C aerobically for 2 days and anaerobically for 5 days, respectively, before counting. In addition, the presence and number of staphylococci were assessed by spread‐plating dilution 10−2 and the undiluted sample on selective Staph‐plates  and incubated aerobically at 37°C for 2 days. The experiment was performed on duplicate agar plates. If growth was observed on the Staph‐plates, then one colony was subcultured on the same medium, and the strain was stored in cryotubes containing TSB and glycerol at −80°C. The staphylococcal strains were further identified using CHROMagar™ Staph aureus .CFU counting was performed as described before  and a Plan 100×/1.10 water dipping objective. The excitation/emission maxima were 488/500 nm for SYTO® 9 and 561/785 nm for PI. For each membrane, five z‐stacks (step size 3 μm) were collected (four in the corners and one in the center). Automatic thresholding was applied to the biofilm images and then processed and quantified using Comstat2 software  . Immediately thereafter, membranes were covered with 200 μl of staining solution  and saline) of FilmTracer™ LIVE/DEAD® Biofilm Viability kit (Molecular Probes) and incubated at RT for 30 min in the dark, in order to stain live (green) and dead (red) cells. Thereafter, stain was removed, and membranes were immersed in saline for 3/μm2) which is volume per unit area representing how much of the image stack is covered by bacteria (live and dead);Biofilm biomass (μmAverage thickness of the biofilm (μm) is the average of all set pixels in the 2D image, which informs about the average height of the biofilm, ignoring the presence of pores or voids in the biofilm;Area occupied (%) by the first biofilm layer is the area occupied by biomass in the first stack image;2/μm3) reflects the fraction of the biofilm that is exposed to the nutrient flow.Surface to volume ratio  for 2 hr at 4°C, rinsed again with 0.15 M Na‐cacodylate buffer, dehydrated in a graded ethanol series  and allowed to air‐dry overnight. The samples were then mounted on aluminum stubs using conductive silver paint and Au sputter‐coated (~15 nm) for scanning electron microscopy (SEM)  operated in the secondary electron mode at 5 kV accelerating voltage and ~5 mm working distance.At 4 and 24 hr, the respective six membrane samples (for each time point) containing biofilms were carefully rinsed in saline and fixed in modified Karnovsky's fixative for 2 hr at 4°C, rinsed with 0.15 M Na‐cacodylate buffer, stained with 1% osmium tetroxide  counting of staphylococci at baseline, 4 and 24 hr. Statistical analyses were performed with GraphPad Prism version 8.1.0 for macOS .The comparisons between test and control membranes, as well as between test or control membranes versus teeth, were statistically evaluated as nonparametric paired samples where Wilcoxon matched‐pairs signed rank test was used. Friedman test was applied to compare time‐points within the three different groups . Mean values ± 3All 120 applied membranes on the tooth surfaces of the 12 volunteers were available for analyses after the respective biofilm accumulation periods.Staphylococcus aureus.Between the early 4 hr) and late (24 hr) time points, viable CFU counts increased on all membranes, with no difference between test and control Figure . The num hr and lQuantitative analysis of biofilm CLSM images showed an increase in biomass of live cells and a reduction of dead biomass between 4 and 24 hr for both test and control membranes Figure . The amoBased on qualitative SEM analysis, at 4 hr, oral bacteria colonized the membrane surface in sparsely populated monolayers, leaving large areas of the membrane surface visible Figure . In comp4in vivo microbiological behavior on barrier membranes when exposed to plaque formation in the oral cavity.A deeper insight on the microbial communities at their natural habitats is critical to improve our knowledge on the role that bacterial colonization plays in the regenerative procedures. In the present study, a novel combination of a clinical model for dental biofilm formation, together with different analytical procedures for bacterial biofilm characterization, is introduced. The model and the experimental setup were employed to investigate the In the present study, it was demonstrated that the two types of nonresorbable membranes were colonized by a diverse bacterial flora. The present new generation of e‐PTFE is made up of two homogenous layers where the inner layer is characterized by a more multidirectional orientation of the PTFE fibrils compared to the outer layer. Its topography consists of an open microstructure of the inner layer of the membrane, intended to face the bone compartment, that would favor the regeneration capacity by increasing the areas of bone ingrowth into the fibrils. On the other hand, the semiopen structure of the outer layer would allow the adhesion of connective tissue cells and fibers thus promoting wound stability and soft‐tissue integration. Due to its semiopen structure, the outer surface of the e‐PTFE membrane may theoretically become a potential trap for bacteria during intraoral manipulation and/or after membrane exposure. The surface topography and roughness are recognized to be of utmost importance in the extent of adhesion that is essential for a successful biofilm growth phase  and surface free energy  did not differ between test and control membranes meaning that the first bacterial cells adhered to both membranes in a similar manner finding new empty areas to attach. However, the development and 3D structure of biofilms after the initial adhesion was markedly different between e‐ and d‐PTFE, as measured by the other CLSM parameters, especially at the early time point (4 hr). The total biofilm biomass and average thickness of the live and dead cell populations were significantly greater on d‐PTFE membrane after 4 hr exposure to the oral cavity. Despite not statistically significant, a similar trend was observed after 24 hr.S. oralis) from the outer to the inner surface of this new generation of dual‐layered e‐PTFE membranes  in order to protect the grafting material and the initial healing clot from bacterial contamination  were classified into five biofilm morphotypes. The results from that study pointed to the fact that the biofilm formation capacity and the structure of the formed biofilm is a complex multifactorial cell–cell adhesion process, which involves complex adaptive genetic mechanisms. Moreover, grouping the isolates into three separate clades showed that the isolates of the disease‐associated clade displayed the most diverse biofilm morphotype  when the barrier membranes were introduced in the oral cavity compared to baseline samples (4/12). Staphylococci have long been recognized as benign members of the skin flora, but many species, such as S. aureus and S. epidermidis, have the capacity to be opportunistic pathogens. Their ability to attach to surfaces and to evade the host defense system leads to the development of refractory biofilm communities that have been linked to a variety of infections, including endocarditis  was reported at subject level in a Greek population that was either healthy or suffering from periodontal disease . Moreover, an advantage here is that the study also compared some of the characteristics of the membrane‐formed biofilm with the tooth‐formed biofilm .5in vitro findings on less bacterial penetration from the outer surface, this findings may lead to a change in the traditional view of e‐PTFE behavior in cases of exposure to the oral environment and would provide new bases for the selection of such barrier for different clinical situations, for example socket preservation where the membrane could be left intentionally exposed. The increased presence of Staphylococcus spp. overtime on the two membrane types raises the question for a possible adjustment of antimicrobial strategies, targeting these species, in conjunction with GBR treatment.Results from this study show that the expanded multifibrillar and semiopen structure of a nonresorbable PTFE membrane elicit less biofilm biomass accumulation and biofilm thickness in contrast to solid dense PTFE. Together with previous All authors declare no conflict of interest.


The presented case will shed some light on one of the rarest complications of HBSE disease, which is acute chest syndrome, and will highlight the management of that complication. The presented case will shed some light on one of the rarest complications of HBSE disease, which is acute chest syndrome, and will highlight the management of that complication. Most reports suggest that HBSE is generally a benign condition with few reported complications like vaso‐occlusive crises, acute chest syndrome, and bone necrosis. In this report, we describe a 17‐year‐old male patient presenting with acute chest syndrome treated with exchange transfusion.HBS, which is the hemoglobin type responsible for sickle cell disease, is localized mostly in Africa, India, and some parts of the Middle East.Acute chest syndrome is considered the most common cause of death in sickle cell disease patients. It is defined by the presence of new radiographic pulmonary infiltrates as well as fever and respiratory symptoms. Management ranges from pain control and fluid replacement in mild disease to simple transfusion or exchange transfusion in more severe presentations.2A 17‐year‐old Arabic male patient who is known to have HBSE disease, presented with a history of chest and back pain for few days prior to admission. He also complained of a non‐productive cough for 2 days but denied fever. On examination, his heart rate was 110 and his respiratory rate was around 25 with a normal temperature of 36.9. On chest exam, he had left basal crackles with decreased air entry.Initial laboratory investigations are mentioned in Table His chest x‐ray showed left retrocardiac and left lower lung zone opacity suggesting left lower lobe consolidation, shown in Figure .The patient was diagnosed to have community‐acquired pneumonia and started on ceftriaxone 1000 mg daily for seven days and azithromycin 500 mg daily for three days as an inpatient. The patient did not improve and started requiring oxygen two days after admission, he became more tachypneic and tachycardiac so he was shifted to the medical intensive care unit and started on non‐invasive ventilation, COVID‐19 and all cultures were negative. Hematology recommended doing hemoglobin electrophoresis for the patient considering the possibility of acute chest syndrome. Hemoglobin electrophoresis was done and it showed the findings in Table The patient underwent a session of exchange transfusion, then during the following days, the patient improved gradually and was discharged from the hospital 4 days after the exchange transfusion. He was commenced on folic acid 5 mg daily and hydroxyurea 500 mg twice a day as prophylaxis, with close follow‐up in hematology clinics.3HBS molecule is a result of the replacement of the hydrophilic glutamic acid by the hydrophobic valine residue at position 6 in the beta‐globin chain. This mutation results in the sickle shape of the affected hemoglobin molecule, which changes to that shape when deoxygenated in certain situations like infections.HBE molecule was first identified and reported independently in 1954.+ thalassemia.HBSE disease on the other hand is considered a benign condition in general. However, David Masiello et al.Sickling associated complications in HBSE disease are thought to occur more commonly in people aged more than 20, but some reports described young patients with this disease who had severe complications as well. A review was done in turkey (An area with a high rate of consanguinity) reported 20 patients with HBSE disease, two of them had mild vaso‐occlusive crises and one who was diagnosed with the disease at age of 11 and was started on hydroxyurea, suffered from cerebrovascular stroke later on.One of the organs that is commonly affected in sickle cell disease patients is the eye. Many complications can occur including anterior and posterior segments ischemia, iris infarction, Erythrocyte‐induced glaucoma which may occur in sickle cell disease patients following traumatic or post‐surgical hyphema, and proliferative sickle retinopathy, which in particular happens more in milder genotypes like SC or S‐B thalassemia than in the SS genotype.Acute chest syndrome is uncommon to happen in patients with HBSE disease. Upon reviewing the literature, we found 5 cases of HBSE disease complicated by acute chest syndrome.4HBSE disease is thought to be a benign condition, but more and more reports are being published describe complicated HBSE disease. An increased number of cases of HBSE disease is expected with the increasing rate of migrations and interracial marriages. This warrants close follow‐up of such patients and early recognition and management of the complications of this disease especially the severe ones like acute chest syndrome.The authors report no conflicts of interest in this work.Ibrahim Khamees: manuscript writing and literature review. Waail rozi: case presentation writing. Mohamed A Yassin: mentorship, manuscript writing, and literature review.Written informed consent was obtained from the patient to allow the publication of information including images. Case approved by HMC Medical Research Center.Data available on request due to privacy/ethical restrictions.


Representatives of this class featuring a chelate substructure formed by an iodo‐substituted benzylidene unit react with (substituted) 2‐isopropoxystyrene to give prototypical “second‐generation” Grubbs‐Hoveyda complexes for olefin metathesis. The new approach to this venerable catalyst family is safe and versatile as it uses a triple bond rather than phenyldiazomethane as the ultimate carbene source and does not require any sacrificial phosphines.The newly discovered light‐driven  On the spot: Light‐driven gem hydrogenation elicits the inherent vic‐dicarbene character of a triple bond. This unusual reactivity mode can be harnessed in the form of a novel, safe, convenient and efficient approach to second‐generation “Grubbs‐Hoveyda”‐type ruthenium carbene complexes for olefin metathesis that relies on the use of alkynes rather than diazoalkanes as the ultimate carbene sources. The new approach therefore constitutes an alternative to the use of propargyl alcohols (or chlorides), which enjoy widespread use as carbene sources.[vic‐dicarbene character of a triple bond through gem hydrogenation provides an attractive alternative that merits further investigation. Studies along these lines are being pursued in our laboratory.The catalytic activity of the new iodo‐chelate complexes thus formed is akin to that of their analogues previously described in the literature;22, 31The authors declare no conflict of interest.As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be re‐organized for online delivery, but are not copy‐edited or typeset. Technical support issues arising from supporting information (other than missing files) should be addressed to the authors.SupplementaryClick here for additional data file.


Owing to the intensified conditions in flow, the reaction time can be reduced from 12–48 hours to only 5–15 minutes. Finally, kinetic measurements highlight how the intensified conditions do not change the reaction mechanism but reliably speed up the overall process.Herein, we report a photocatalytic procedure that enables the acylation/arylation of unfunctionalized alkyl derivatives in flow. The method exploits the ability of the decatungstate anion to act as a hydrogen atom abstractor and produce nucleophilic carbon‐centered radicals that are intercepted by a nickel catalyst to ultimately forge C(sp Need for speed: An efficient and fast photocatalytic procedure that enables the acylation/arylation of unfunctionalized alkyl derivatives in flow has been realized by combining decatungstate photocatalysis and nickel catalysis. The methodology shows great functional group tolerance and high regioselectivity, and can be used for the late‐stage functionalization of various biologically‐relevant molecules. This can be ascribed to the bulky size of the decatungstate anion which allows to discriminate different C(sp3)−H bonds based on steric hindrance, which sets it apart from halogen radical HAT catalysis. Furthermore, despite the presence of a transition metal catalyst, this protocol tolerates well bromide substituents  or exocyclic double bonds , which should serve as entry points for further decoration of the organic scaffold. Finally, to showcase the high selectivity and the synthetic applicability of this method, we performed the late‐stage functionalization of complex organic or natural scaffolds such as eucalyptol  and sclareolide . The latter examples serve as a highlight of the superior selectivity that can be obtained using TBADT as HAT photocatalyst. Indeed, in contrast to the use of halogen radicals, no erosion of the selectivity was observed by functionalization of other C−H bonds within these complex organic scaffolds.Next, we evaluated the scope of the H‐donors amenable to the developed acylation methodology. Our protocol enables selective modification of various five‐membered rings, including cyclopentane , heteroarenes  and electron‐donating substituents33 and 34, 36 % and 33 % yield, respectively) all swiftly reacted to yield the corresponding products. Concerning the scope of the H‐donors, both α‐to‐O , α‐to‐N  and benzylic  C−H bonds could be readily arylated. Similarly to the acylation procedure, norbornane proved to be a competent substrate . Finally, late‐stage functionalization of sclareolide  and ambroxide  confirmed the synthetic utility of this process.After having established the acylation procedure, we wondered whether we could improve the aforementioned slow reaction kinetics in the arylative process reported by MacMillan and co‐workers.3)−H bonds, but has no apparent influence on the reaction mechanism.To understand the difference in reaction rates between the flow and batch setups and its potential effect on the developed methodology, we monitored the kinetic profiles of the two reactions Scheme . While tIn conclusion, we have reported a practical procedure that allows the acylation and arylation of strong aliphatic bonds in flow. Thanks to the microfluidic setup, this transformation takes only 5–15 minutes and is readily scalable. Due to the mild reaction conditions, the methodology shows great functional group tolerance and high regioselectivity, and can be used for the late‐stage functionalization of various complex biologically‐relevant molecules. Kinetic studies show that the combination of a microfluidic environment and powerful light sources has influence on the overall rate of the reaction without affecting the mechanism.The authors declare no conflict of interest.As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be re‐organized for online delivery, but are not copy‐edited or typeset. Technical support issues arising from supporting information (other than missing files) should be addressed to the authors.Supporting InformationClick here for additional data file.