TRPM2 and CaMKII signaling drives excessive GABAergic synaptic inhibition following ischemia.

Excitotoxicity and the concurrent loss of inhibition are well-defined mechanisms driving acute elevation in excitatory/ inhibitory (E/I) balance and neuronal cell death following an ischemic insult to the brain. Despite the high prevalence of long-term disability in survivors of global cerebral ischemia (GCI) as a consequence of cardiac arrest, it remains unclear whether E/I imbalance persists beyond the acute phase and negatively affects functional recovery. We previously demonstrated sustained impairment of long-term potentiation (LTP) in hippocampal CA1 neurons correlating with deficits in learning and memory tasks in a murine model of cardiac arrest/ cardiopulmonary resuscitation (CA/CPR). Here, we use CA/CPR and an in vitro ischemia model to elucidate mechanisms by which E/I imbalance contributes to ongoing hippocampal dysfunction in male mice. We reveal increased postsynaptic GABAA receptor (GABAAR) clustering and function in the CA1 region of the hippocampus that reduces E/I ratio. Importantly, reduced GABAAR clustering observed in the first 24 hours rebounds to an elevation of GABAergic clustering by 3 days post-ischemia. This increase in GABAergic inhibition required activation of the Ca2+-permeable ion channel transient receptor potential melastatin-2 (TRPM2), previously implicated in persistent LTP and memory deficits following CA/CPR. Furthermore, we find Ca2+-signaling, likely downstream of TRPM2 activation, upregulates Ca2+/calmodulin-dependent protein kinase II (CaMKII) activity, thereby driving the elevation of postsynaptic inhibitory function. Thus, we propose a novel mechanism by which inhibitory synaptic strength is upregulated in the context of ischemia and identify TRPM2 and CaMKII as potential pharmacological targets to restore perturbed synaptic plasticity and ameliorate cognitive function.Significance Statement Excitatory/ inhibitory (E/I) imbalance drives long-term disability in numerous central nervous system disorders, including cerebral ischemia. Previous studies indicated ischemia-induced hippocampal synaptic plasticity deficits contribute to long-term cognitive impairment, yet the mechanisms underlying hippocampal dysfunction are poorly defined. Here, we combine in vivo and in vitro approaches to demonstrate elevated GABAA receptor clustering and function contribute to a reduction in hippocampal E/I balance and deficits in long-term potentiation at delayed timepoints following ischemia. We further identify ongoing activation of the TRPM2 ion channel and Ca2+-dependent kinase, CaMKII, are required for the ischemia-induced enhancement of GABAergic synaptic inhibition, highlighting promising new targets to improve post-ischemic long-term functional recovery.

What's in a name? Political and economic concepts differ in social media references to harmful algae blooms.

Policies and management decisions in the marine environment are driven in part by public sentiment which can grow more intense during hazard events like Harmful Algae Blooms (HABs). The public conversations on social media sites like Twitter (before X) reveal the polarized nature of HABs through nuanced language and sentiment. This article uses mixed methods of machine learned topic modeling and inductive qualitative coding to describe the ways the long-term 2017-2019 Karenia brevis "red tide" bloom were politicized across Florida's South West coast. It finds that there are topical differences in keywords related to place (e.g. beach, Florida, coast), agent (individual or organization), and epistemic values (reliance on scientific and/or media reports). These topical differences demonstrate different levels of politicization and partisanship in qualitative analysis. Conceptually, this research demonstrates the ways different dimensions of a long-duration marine hazard can be polarized. Regarding management, this research provides insights to political and organizational stakeholders and the gaps in the discourse shaping marine hazards which can be used to strategically guide future social media engagement to manage politicization. What if all the careful work that resource and environmental managers do can be undone by simple, seemingly uncontroversial words? In an era of increased environmental and marine distress-coupled with short format communication-the ways environmental managers choose their words is crucial, even between ostensibly inconsequential nouns like "red tide" or "algae bloom." Policies and management decisions in the marine environment are driven in part by public sentiment which can grow more intense during hazard events like Harmful Algae Blooms (HABs). The public conversations on social media sites like Twitter (before X) reveal the polarized nature of HABs through nuanced language and sentiment. This article relies on mining social media posts, and uses mixed methods of machine-learned topic modeling and human-driven inductive qualitative coding to describe the ways the long-term 2017-2019 Karenia brevis "red tide" blooms were politicized across Florida's South West coast. It finds that there are topical differences in keywords related to place (e.g. beach, Florida, coast), agent (individual or organization), and epistemic values (reliance on scientific and/or media reports). These topical differences demonstrate different levels of politicization and partisanship in qualitative analysis. Conceptually, this research demonstrates the ways different dimensions of a long-duration marine hazard can be polarized. Regarding management, this research provides insights to political and organizational stakeholders and the gaps in the discourse shaping marine hazards which can be used to strategically guide future social media engagement to manage politicization.

Non-linear impacts of harmful algae blooms on the coastal tourism economy.

Harmful algae blooms (HABs) occur in water bodies throughout the globe and can have multi-faceted impacts on tourism. However, little is known of the magnitude of economic losses to the tourism sector as a result of HABs. There is limited understanding of the empirical relationships between HAB intensity and duration, and the effects of this phenomenon on the tourism sector. This study is based in the state of Florida, USA, a notable sun, sand, and sea destination in the western hemisphere, where blooms of a marine harmful algae are a recurrent threat to coastal tourism. The empirical framework is based on a month and county-level panel database that combines sales by tourism-related businesses with observations from the official HAB surveillance system of the state of Florida. We use time and space fixed-effects regressions to estimate the loss in tourism revenue associated with one additional day of red tide. Results indicate that impacts of HABs on tourism do not follow a linear pattern with increasing HAB concentrations, but rather appear to follow an inverted-U pattern. In other words, higher concentrations of the HAB organism do not necessarily imply higher economic losses, suggesting that the impacts of HABs on tourism are not driven solely by the biophysical element of cell density. Rather, these impacts appear to be mediated and amplified by human dimensions. The loss to tourism-related businesses due to the 2018 Florida red tide bloom was estimated to be $2.7 billion USD, which implies that HABs and their impact on tourism can be considered as a potential 'billion-dollar' disaster.

Factors Associated with Cancer Prevention/Risk Reduction Behaviors among Latinos.

Improving understanding of behaviors that increase or reduce cancer risk for different Hispanic groups is a public health priority; such knowledge is sparse in new gateway immigration locations such as Indiana. The aims of this study were to: 1) describe cancer beliefs and cancer preventive/risk reduction behaviors (physical activity, tobacco, and alcohol use) among Hispanic adults; 2) examine differences in cancer beliefs and preventive behaviors by country/territory of birth, socioeconomic status, and area of residence (urban vs. rural); and 3) determine predictors of engagement in cancer prevention and risk reduction behaviors in this population. A cross-sectional online survey targeted adult Indiana residents who identified as Latino, Hispanic, or Spanish recruited using Facebook-targeted advertising. Complete survey data from 1520 respondents were analyzed using descriptive, unadjusted, and adjusted models. The majority of respondents believed they were unlikely to get cancer but held many other fatalistic beliefs about cancer. Only 35.6% of respondents had received the HPV vaccine, 37.6% reported they were currently smoking cigarettes, and 64% reported occasional or frequent drinking of alcohol. Respondents spent an average of 3.55 days per week engaged in moderate exercise. Differences were observed by country/territory of birth, income, and education but not by rural residence status. Predictors of cancer risk/risk reduction behaviors were identified. The Hispanic population in Indiana is diverse and effective interventions for cancer prevention should be culturally targeted based on country/territory of birth and individually tailored based on cancer-related beliefs.

Novel differential calcium regulation of hematopoietic stem and progenitor cells under physiological low oxygen conditions.

Low oxygen bone marrow (BM) niches (~1%-4% low O2 ) provide critical signals for hematopoietic stem/progenitor cells (HSC/HSPCs). Our presented data are the first to investigate live, sorted HSC/HSPCs in their native low O2 conditions. Transcriptional and proteomic analysis uncovered differential Ca2+ regulation that correlated with overlapping phenotypic populations consisting of robust increases of cytosolic and mitochondrial Ca2+ , ABC transporter (ABCG2) expression and sodium/hydrogen exchanger (NHE1) expression in live, HSC/HSPCs remaining in constant low O2. We identified a novel Ca2+ high population in HSPCs predominantly detected in low O2 that displayed enhanced frequency of phenotypic LSK/LSKCD150 in low O2 replating assays compared to Ca2+ low populations. Inhibition of the Ca2+ regulator NHE1 (Cariporide) resulted in attenuation of both the low O2 induced Ca2+ high population and subsequent enhanced maintenance of phenotypic LSK and LSKCD150 during low O2 replating. These data reveal multiple levels of differential Ca2+ regulation in low O2 resulting in phenotypic, signaling, and functional consequences in HSC/HSPCs.

Rett syndrome severity estimation with the BioStamp nPoint using interactions between heart rate variability and body movement.

Rett syndrome, a rare genetic neurodevelopmental disorder in humans, does not have an effective cure. However, multiple therapies and medications exist to treat symptoms and improve patients' quality of life. As research continues to discover and evaluate new medications for Rett syndrome patients, there remains a lack of objective physiological and motor activity-based (physio-motor) biomarkers that enable the measurement of the effect of these medications on the change in patients' Rett syndrome severity. In our work, using a commercially available wearable chest patch, we recorded simultaneous electrocardiogram and three-axis acceleration from 20 patients suffering from Rett syndrome along with the corresponding Clinical Global Impression-Severity score, which measures the overall disease severity on a 7-point Likert scale. We derived physio-motor features from these recordings that captured heart rate variability, activity metrics, and the interactions between heart rate and activity. Further, we developed machine learning (ML) models to classify high-severity Rett patients from low-severity Rett patients using the derived physio-motor features. For the best-trained model, we obtained a pooled area under the receiver operating curve equal to 0.92 via a leave-one-out-patient cross-validation approach. Finally, we computed the feature popularity scores for all the trained ML models and identified physio-motor biomarkers for Rett syndrome.

Cancer-related knowledge, beliefs, and behaviors among Hispanic/Latino residents of Indiana.

BACKGROUND: Cancer is the leading cause of death for Hispanics in the USA. Screening and prevention reduce cancer morbidity and mortality. METHODS: This study administered a cross-sectional web-based survey to self-identified Hispanic residents in the state of Indiana to assess their cancer-related knowledge, beliefs, and behaviors, as well as to identify what factors might be associated with cancer screening and prevention. Chi-square and Fisher's exact test were used to compare associations and logistic regression used to develop both univariate and multivariate regression models. RESULTS: A total of 1520 surveys were completed, median age of respondents was 53, 52% identified as men, 50.9% completed the survey in Spanish, and 60.4% identified the USA as their country of birth. Most were not able to accurately identify ages to begin screening for breast, colorectal, or lung cancer, and there were significant differences in cancer knowledge by education level. US-born individuals with higher income and education more often believed they were likely to develop cancer and worry about getting cancer. Sixty eight percent of respondents were up-to-date with colorectal, 44% with breast, and 61% with cervical cancer screening. Multivariate models showed that higher education, lack of fatalism, older age, lower household income, and unmarried status were associated with cervical cancer screening adherence. CONCLUSIONS: Among a Hispanic population in the state of Indiana, factors associated with cervical cancer screening adherence were similar to the general population, with the exceptions of income and marital status. Younger Hispanic individuals were more likely to be adherent with breast and colorectal cancer screening, and given the higher incidence of cancer among older individuals, these results should guide future research and targeted outreach.

The Role of Influential Actors in Fostering the Polarized COVID-19 Vaccine Discourse on Twitter: Mixed Methods of Machine Learning and Inductive Coding.

Background: Since COVID-19 vaccines became broadly available to the adult population, sharp divergences in uptake have emerged along partisan lines. Researchers have indicated a polarized social media presence contributing to the spread of mis- or disinformation as being responsible for these growing partisan gaps in uptake. Objective: The major aim of this study was to investigate the role of influential actors in the context of the community structures and discourse related to COVID-19 vaccine conversations on Twitter that emerged prior to the vaccine rollout to the general population and discuss implications for vaccine promotion and policy. Methods: We collected tweets on COVID-19 between July 1, 2020, and July 31, 2020, a time when attitudes toward the vaccines were forming but before the vaccines were widely available to the public. Using network analysis, we identified different naturally emerging Twitter communities based on their internal information sharing. A PageRank algorithm was used to quantitively measure the level of "influentialness" of Twitter accounts and identifying the "influencers," followed by coding them into different actor categories. Inductive coding was conducted to describe discourses shared in each of the 7 communities. Results: Twitter vaccine conversations were highly polarized, with different actors occupying separate "clusters." The antivaccine cluster was the most densely connected group. Among the 100 most influential actors, medical experts were outnumbered both by partisan actors and by activist vaccine skeptics or conspiracy theorists. Scientists and medical actors were largely absent from the conservative network, and antivaccine sentiment was especially salient among actors on the political right. Conversations related to COVID-19 vaccines were highly polarized along partisan lines, with "trust" in vaccines being manipulated to the political advantage of partisan actors. Conclusions: These findings are informative for designing improved vaccine information communication strategies to be delivered on social media especially by incorporating influential actors. Although polarization and echo chamber effect are not new in political conversations in social media, it was concerning to observe these in health conversations on COVID-19 vaccines during the vaccine development process.

The breathing human infrastructure: Integrating air quality, traffic, and social media indicators.

Outdoor air pollution is a complex system that is responsible for the deaths of millions of people annually, yet the integration of interdisciplinary data necessary to assess air quality's multiple metrics is still lacking. This case study integrates atmospheric indicators (concentrations of criteria pollutants including particulate matter and gaseous pollutants), traffic indicators (permanent traffic monitoring station data), and social indicators (community responses in Twitter archives) representing the interplay of the three critical pillars of the United Nations' Triple Bottom Line: environment, economy, and society. During the watershed moment of the COVID-19 pandemic lockdowns in Florida, urban centers demonstrated the gaps and opportunities for understanding the relationships, through correlations rather than causations, between urban air quality, traffic emissions, and public perceptions. The relationship between the perception and the traffic variables were strongly correlated, however no correlation was observed between the perception and actual air quality indicators, except for NO2. These observations might consequently infer that traffic serves as people's proxy for air quality, regardless of actual air quality, suggesting that social media messaging around asthma may be a way to monitor traffic patterns in areas where no infrastructure currently exists or is prohibited to build. It also indicates that people are less likely to be reliable sensors to accurately measure air quality due to bias in their observations of traffic volume and/or confirmation biases in broader social discourse. Results presented herein are of significance in demonstrating the capacity for interdisciplinary studies to consider the predictive capacities of social media and air pollution, its use as both lever and indicator of public support for air quality legislation and clean-air transitions, and its ability to overcome limitations of surface monitoring stations.

The COVID-19 vaccine social media infodemic: healthcare providers' missed dose in addressing misinformation and vaccine hesitancy.

During the COVID-19 pandemic, antivaccination social media accounts are proliferating online, threatening to further escalate vaccine hesitancy related to the COVID-19 vaccine. This commentary seeks to alert and encourage the health care provider community, including health care professionals and academic organizations, to engage in social media to counter the mounting vaccine-related infodemic. To validate our recommendation for engagement, the authors describe preliminary findings using a mixed methods approach of quantitative Twitter-based ranking algorithms of networks and users with qualitative content analysis of 1 million tweets related to COVID-19 vaccine conversations. Results show highly polarized and active antivaccine conversations that were primarily influenced by political and nonmedical Twitter users. In contrast, less than 10% of the tweets stemmed from the medical community, demonstrating a lack of active health care professional connectivity in addressing COVID-19 misinformation. The authors introduce the concept of Health Care Provider Social Media Hesitancy to refer to the public health threat of health care providers' nonaction in providing pro-vaccine and scientific information about the vaccine on social media. The authors conclude by describing multilevel strategies for encouraging health care providers and the medical community to effectively "Tweet up" to combat the mounting threat of vaccine misinformation and hesitancy.

Gender differences in question-asking at the 2019 American Society of Hematology Annual Meeting.

Attendance at professional conferences is an important component of career development, because conferences are a major forum for presenting new research, interacting with colleagues and networking. An extensive literature documents differences in the professional experiences of women and men, including experiences at professional conferences. We hypothesized that women are less likely than men to ask questions at conferences, thus forgoing opportunities for professional development. To address this issue, we analyzed the question-asking behavior of women and men at the 2019 Annual Meeting and Exposition of the American Society of Hematology. In all, 112 sessions (55% of those eligible) were randomly chosen for coding, yielding data on 577 presentations. Although approximately 50% of moderators and speakers were women, the proportion of questions asked by women was significantly lower compared with the estimated proportion of women attending the conference (23% vs 39%; P < .0001). Women were more likely to ask questions if another woman asked the first question or if the session topic was red cells. These results suggest that although women are represented equally as moderators and speakers, they are less likely to engage in the postpresentation discourse by asking questions. Encouraging women to speak up in professional situations and providing training on question-asking skills can help address this gender gap that potentially contributes to disparities in professional visibility and career advancement for women in hematology.

Transcriptome analysis of rat dorsal hippocampal CA1 after an early life seizure induced by kainic acid.

Seizures that occur during early development are associated with adverse neurodevelopmental outcomes. Causation and mechanisms are currently under investigation. Induction of an early life seizure by kainic acid (KA) in immature rats on post-natal day (P) 7 results in behavioral changes in the adult rat that reflect social and intellectual deficits without overt cellular damage. Our previous work also demonstrated increased expression of CA1 hippocampal long-term potentiation (LTP) and reduced desensitization of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid-type ionotropic glutamate receptors (AMPA-R) one week following a kainic acid induced seizure (KA-ELS). Here we used RNA sequencing (RNAseq) of mRNA from dorsal hippocampal CA1 to probe changes in mRNA levels one week following KA-ELS as a means to investigate the mechanisms for these functional changes. Ingenuity pathway analysis (IPA) confirmed our previous results by predicting an up-regulation of the synaptic LTP pathway. Differential gene expression results revealed significant differences in 7 gene isoforms. Additional assessments included AMPA-R splice variants and adenosine deaminase acting on RNA 2 (ADAR2) editing sites as a means to determine the mechanism for reduced AMPA-R desensitization. Splice variant analysis demonstrated that KA-ELS result in a small, but significant decrease in the "flop" isoform of Gria3, and editing site analysis revealed significant changes in the editing of a kainate receptor subunit, Grik2, and a serotonin receptor, Htr2c. While these specific changes may not account for altered AMPA-R desensitization, the differences indicate that KA-ELS alters gene expression in the hippocampal CA1 one week after the insult.

Electroencephalographic spectral power as a marker of cortical function and disease severity in girls with Rett syndrome.

BACKGROUND: Rett syndrome is a neurodevelopmental disorder caused by a mutation in the X-linked MECP2 gene. Individuals with Rett syndrome typically develop normally until around 18 months of age before undergoing a developmental regression, and the disorder can lead to cognitive, motor, sensory, and autonomic dysfunction. Understanding the mechanism of developmental regression represents a unique challenge when viewed through a neuroscience lens. Are circuits that were previously established erased, and are new ones built to supplant old ones? One way to examine circuit-level changes is with the use of electroencephalography (EEG). Previous studies of the EEG in individuals with Rett syndrome have focused on morphological characteristics, but few have explored spectral power, including power as an index of brain function or disease severity. This study sought to determine if EEG power differs in girls with Rett syndrome and typically developing girls and among girls with Rett syndrome based on various clinical characteristics in order to better understand neural connectivity and cortical organization in individuals with this disorder. METHODS: Resting state EEG data were acquired from girls with Rett syndrome (n = 57) and typically developing children without Rett syndrome (n = 37). Clinical data were also collected for girls with Rett syndrome. EEG power across several brain regions in numerous frequency bands was then compared between girls with Rett syndrome and typically developing children and power in girls with Rett syndrome was compared based on these clinical measures. 1/ƒ slope was also compared between groups. RESULTS: Girls with Rett syndrome demonstrate significantly lower power in the middle frequency bands across multiple brain regions. Additionally, girls with Rett syndrome that are postregression demonstrate significantly higher power in the lower frequency delta and theta bands and a significantly more negative slope of the power spectrum. Increased power in these bands, as well as a more negative 1/ƒ slope, trended with lower cognitive assessment scores. CONCLUSIONS: Increased power in lower frequency bands is consistent with previous studies demonstrating a "slowing" of the background EEG in Rett syndrome. This increase, particularly in the delta band, could represent abnormal cortical inhibition due to dysfunctional GABAergic signaling and could potentially be used as a marker of severity due to associations with more severe Rett syndrome phenotypes.

BEAPP: The Batch Electroencephalography Automated Processing Platform.

Electroencephalography (EEG) offers information about brain function relevant to a variety of neurologic and neuropsychiatric disorders. EEG contains complex, high-temporal-resolution information, and computational assessment maximizes our potential to glean insight from this information. Here we present the Batch EEG Automated Processing Platform (BEAPP), an automated, flexible EEG processing platform incorporating freely available software tools for batch processing of multiple EEG files across multiple processing steps. BEAPP does not prescribe a specified EEG processing pipeline; instead, it allows users to choose from a menu of options for EEG processing, including steps to manage EEG files collected across multiple acquisition setups (e.g., for multisite studies), minimize artifact, segment continuous and/or event-related EEG, and perform basic analyses. Overall, BEAPP aims to streamline batch EEG processing, improve accessibility to computational EEG assessment, and increase reproducibility of results.

Analysis of the CaMKIIα and ß splice-variant distribution among brain regions reveals isoform-specific differences in holoenzyme formation.

Four CaMKII isoforms are encoded by distinct genes, and alternative splicing within the variable linker-region generates additional diversity. The α and ß isoforms are largely brain-specific, where they mediate synaptic functions underlying learning, memory and cognition. Here, we determined the α and ß splice-variant distribution among different mouse brain regions. Surprisingly, the nuclear variant αB was detected in all regions, and even dominated in hypothalamus and brain stem. For CaMKIIß, the full-length variant dominated in most regions (with higher amounts of minor variants again seen in hypothalamus and brain stem). The mammalian but not fish CaMKIIß gene lacks exon v3N that encodes the nuclear localization signal in αB, but contains three exons not found in the CaMKIIα gene (exons v1, v4, v5). While skipping of exons v1 and/or v5 generated the minor splice-variants ß', ße and ße', essentially all transcripts contained exon v4. However, we instead detected another minor splice-variant (now termed ßH), which lacks part of the hub domain that mediates formation of CaMKII holoenzymes. Surprisingly, in an optogenetic cellular assay of protein interactions, CaMKIIßH was impaired for binding to the ß hub domain, but still bound CaMKIIα. This provides the first indication for isoform-specific differences in holoenzyme formation.

Placebo-controlled crossover assessment of mecasermin for the treatment of Rett syndrome.

Objective: To measure the efficacy of mecasermin (recombinant human insulin-like growth factor 1, rhIGF-1), for treating symptoms of Rett syndrome (RTT) in a pediatric population using a double-blind crossover study design. Methods: Thirty girls with classic RTT in postregression stage were randomly assigned to placebo or rhIGF-1 in treatment period 1 and crossed over to the opposite assignment for period 2 (both 20 weeks), separated by a 28-week washout period. The primary endpoints were as follows: Anxiety Depression and Mood Scale (ADAMS) Social Avoidance subscale, Rett Syndrome Behaviour Questionnaire (RSBQ) Fear/Anxiety subscale, Parent Target Symptom Visual Analog Scale (PTSVAS) top three concerns, Clinical Global Impression (CGI), Parent Global Impression (PGI), and the Kerr severity scale. Cardiorespiratory- and electroencephalography (EEG)-based biomarkers were also analyzed. Results: There were no significant differences between randomization groups. The majority of AEs were mild to moderate, although 12 episodes of serious AEs occurred. The Kerr severity scale, ADAMS Depressed Mood subscale, Visual Analog Scale Hyperventilation, and delta average power change scores significantly increased, implying worsening of symptoms. Electroencephalography (EEG) parameters also deteriorated. A secondary analysis of subjects who were not involved in a placebo recall confirmed most of these findings. However, it also revealed improvements on a measure of stereotypic behavior and another of social communication. Interpretation: As in the phase 1 trial, rhIGF-1 was safe; however, the drug did not reveal significant improvement, and some parameters worsened.

CaMKII regulates the depalmitoylation and synaptic removal of the scaffold protein AKAP79/150 to mediate structural long-term depression.

Both long-term potentiation (LTP) and depression (LTD) of excitatory synapse strength require the Ca2+/calmodulin (CaM)-dependent protein kinase II (CaMKII) and its autonomous activity generated by Thr-286 autophosphorylation. Additionally, LTP and LTD are correlated with dendritic spine enlargement and shrinkage that are accompanied by the synaptic accumulation or removal, respectively, of the AMPA-receptor regulatory scaffold protein A-kinase anchoring protein (AKAP) 79/150. We show here that the spine shrinkage associated with LTD indeed requires synaptic AKAP79/150 removal, which in turn requires CaMKII activity. In contrast to normal CaMKII substrates, the substrate sites within the AKAP79/150 N-terminal polybasic membrane-cytoskeletal targeting domain were phosphorylated more efficiently by autonomous compared with Ca2+/CaM-stimulated CaMKII activity. This unusual regulation was mediated by Ca2+/CaM binding to the substrate sites resulting in protection from phosphorylation in the presence of Ca2+/CaM, a mechanism that favors phosphorylation by prolonged, weak LTD stimuli versus brief, strong LTP stimuli. Phosphorylation by CaMKII inhibited AKAP79/150 association with F-actin; it also facilitated AKAP79/150 removal from spines but was not required for it. By contrast, LTD-induced spine removal of AKAP79/150 required its depalmitoylation on two Cys residues within the N-terminal targeting domain. Notably, such LTD-induced depalmitoylation was also blocked by CaMKII inhibition. These results provide a mechanism how CaMKII can indeed mediate not only LTP but also LTD through regulated substrate selection; however, in the case of AKAP79/150, indirect CaMKII effects on palmitoylation are more important than the effects of direct phosphorylation. Additionally, our results provide the first direct evidence for a function of the well-described AKAP79/150 trafficking in regulating LTD-induced spine shrinkage.

Classification of respiratory disturbances in Rett Syndrome patients using Restricted Boltzmann Machine.

Rett syndrome (RTT) is a severe neurodevelopmental disorder that can cause pervasive wakeful respiratory disturbances that include tachypnea, breath-holding, and central apnea. Quantitative analysis of these respiratory disturbances in RTT is considered a promising outcome measure for clinical trials. Currently, machine learning methodologies have not been employed to automate the classification of RTT respiratory disturbances. In this paper, we propose using temporal, flow, and autocorrelation features taken from the respiratory inductance plethsymography chest signal. We tested the performance of six classifiers including: Support Vector Machine, Restricted-Boltzmann-Machine, Back-propagation, Levenberg-Marquardt, and Decision-Fusion. We evaluate this classification in two modalities: (1) a subject-independent modality (leave-one-subject-out) obtaining the best F1 score in 93.67%, and (2) a trial-independent modality (leave-one-trial-out per subject) obtaining the best F1 score in 78.21%.