Natural History Research Articles

Declining hunter and trapper mail survey response rates between 1976 and 2020 in illinois

ABSTRACT We examined mail survey response rates between 1976 and 2020. All 129 studies analyzed: (a) were conducted by the Illinois Natural History Survey, (b) sampled the same population (Illinois hunters/trappers), (c) followed identical administration protocols, and (d) had the same structure. The unit of analysis was study year. Across all surveys, the average response rate was 67% (SD=.13) and ranged from a high of 86% (1982) to a low of 36% (2018). Among the waterfowl hunters, response rates ranged from 83% (1981) to 36% (2018). The comparable ranges for upland game hunters were 86% (1982) to 41% (2020), and for trappers the range was 85% (1989) to 50% (2020). The bivariate correlation between study year and response rate was −.95 for waterfowl surveys, −.86 for upland game surveys, and −.84 for trapper surveys. Results highlighted dramatic declines in response rates for all three activities over time.

The stuff of memories: Planning hindsight in animal cryobanks.

Biobanks are becoming ubiquitous infrastructures in zoology and other non-human life sciences. They promise to store frozen research samples for the long term for future use. That use remains speculative but nevertheless needs to be anticipated. Following the establishment of a physical and digital infrastructure for frozen samples in an animal biobanking project, this article explores how the future is anticipated to remember the past, and how frozen objects are shaped accordingly. Situating the biobank between mundane freezing routines in a research lab and the 'dry' and 'wet' collections of natural history museums, I argue that frozen research objects need to be conserved in two separate ways. The unavailability of cryo-objects in cold storage forces researchers to store materials independently of metadata, while retaining a link between them that allows for their reunion after thawing. The result is a split object, leading a double life at sub-zero and room temperature, linked only through the surface of special plastic containers. Following the making of such split objects, this article offers an elaboration of Radin's 'planned hindsight' as well as a reflection on the universality and particularity of biobanks as standardized scientific memory.

Resistance, rebound, and recurrence regrowth patterns in pediatric low-grade glioma treated by MAPK inhibition: A modified Delphi approach to build international consensus-based definitions-International Pediatric Low-Grade Glioma Coalition.

Pediatric low-grade glioma (pLGG) is the most common childhood brain tumor group. The natural history, when curative resection is not possible, is one of a chronic disease with periods of tumor stability and episodes of tumor progression. While there is a high overall survival rate, many patients experience significant and potentially lifelong morbidities. The majority of pLGGs have an underlying activation of the RAS/MAPK pathway due to mutational events, leading to the use of molecularly targeted therapies in clinical trials, with recent regulatory approval for the combination of BRAF and MEK inhibition for BRAFV600E mutated pLGG. Despite encouraging activity, tumor regrowth can occur during therapy due to drug resistance, off treatment as tumor recurrence, or as reported in some patients as a rapid rebound growth within 3 months of discontinuing targeted therapy. Definitions of these patterns of regrowth have not been well described in pLGG. For this reason, the International Pediatric Low-Grade Glioma Coalition, a global group of physicians and scientists, formed the Resistance, Rebound, and Recurrence (R3) working group to study resistance, rebound, and recurrence. A modified Delphi approach was undertaken to produce consensus-based definitions and recommendations for regrowth patterns in pLGG with specific reference to targeted therapies.

Key aspects of papillomavirus infection influence the host cervicovaginal microbiome in a preclinical murine papillomavirus (MmuPV1) infection model.

Human papillomaviruses (HPVs) are the most common sexually transmitted infection in the United States and are a major etiological agent of cancers in the anogenital tract and oral cavity. Growing evidence suggests changes in the host microbiome are associated with the natural history and ultimate outcome of HPV infection. We sought to define changes in the host cervicovaginal microbiome during papillomavirus infection, persistence, and pathogenesis using the murine papillomavirus (MmuPV1) cervicovaginal infection model. Cervicovaginal lavages were performed over a time course of MmuPV1 infection in immunocompetent female FVB/N mice and extracted DNA was analyzed by qPCR to track MmuPV1 viral copy number. 16S ribosomal RNA (rRNA) gene sequencing was used to determine the composition and diversity of microbial communities throughout this time course. We also sought to determine whether specific microbial communities exist across the spectrum of MmuPV1-induced neoplastic disease. We, therefore, performed laser-capture microdissection to isolate regions of disease representing all stages of neoplastic disease progression (normal, low- and high-grade dysplasia, and cancer) from female reproductive tract tissue sections from MmuPV1-infected mice and performed 16S rRNA sequencing. Consistent with other studies, we found that the natural murine cervicovaginal microbiome is highly variable across different experiments. Despite these differences in initial microbiome composition between experiments, we observed that MmuPV1 persistence, viral load, and severity of disease influenced the composition of the cervicovaginal microbiome. These studies demonstrate that papillomavirus infection can alter the cervicovaginal microbiome.IMPORTANCEHuman papillomaviruses (HPVs) are the most common sexually transmitted infection in the United States. A subset of HPVs that infect the anogenital tract (cervix, vagina, anus) and oral cavity cause at least 5% of cancers worldwide. Recent evidence indicates that the community of microbial organisms present in the human cervix and vagina, known as the cervicovaginal microbiome, plays a role in HPV-induced cervical cancer. However, the mechanisms underlying this interplay are not well-defined. In this study, we infected the female reproductive tract of mice with a murine papillomavirus (MmuPV1) and found that key aspects of papillomavirus infection and disease influence the host cervicovaginal microbiome. This is the first study to define changes in the host microbiome associated with MmuPV1 infection in a preclinical animal model of HPV-induced cervical cancer. These results pave the way for using MmuPV1 infection models to further investigate the interactions between papillomaviruses and the host microbiome.

Knowledge Graphs and Pretrained Language Models Enhanced Representation Learning for Conversational Recommender Systems.

Conversational recommender systems (CRSs) utilize natural language interactions and dialog history to infer user preferences and provide accurate recommendations. Due to the limited conversation context and background knowledge, existing CRSs rely on external sources such as knowledge graphs (KGs) to enrich the context and model entities based on their interrelations. However, these methods ignore the rich intrinsic information within entities. To address this, we introduce the knowledge-enhanced entity representation learning (KERL) framework, which leverages both the KG and a pretrained language model (PLM) to improve the semantic understanding of entities for CRS. In our KERL framework, entity textual descriptions are encoded via a PLM, while a KG helps reinforce the representation of these entities. We also employ positional encoding to effectively capture the temporal information of entities in a conversation. The enhanced entity representation is then used to develop a recommender component that fuses both entity and contextual representations for more informed recommendations, as well as a dialog component that generates informative entity-related information in the response text. A high-quality KG with aligned entity descriptions is constructed to facilitate this study, namely, the Wiki Movie Knowledge Graph (WikiMKG). The experimental results show that KERL achieves state-of-the-art results in both recommendation and response generation tasks. Our code is publicly available at the link: https://github.com/icedpanda/KERL.

Dynamics of cognitive variability with age and its genetic underpinning in NIHR BioResource Genes and Cognition cohort participants.

A leading explanation for translational failure in neurodegenerative disease is that new drugs are evaluated late in the disease course when clinical features have become irreversible. Here, to address this gap, we cognitively profiled 21,051 people aged 17-85 years as part of the Genes and Cognition cohort within the National Institute for Health and Care Research BioResource across England. We describe the cohort, present cognitive trajectories and show the potential utility. Surprisingly, when studied at scale, the APOE genotype had negligible impact on cognitive performance. Different cognitive domains had distinct genetic architectures, with one indicating brain region-specific activation of microglia and another with glycogen metabolism. Thus, the molecular and cellular mechanisms underpinning cognition are distinct from dementia risk loci, presenting different targets to slow down age-related cognitive decline. Participants can now be recalled stratified by genotype and cognitive phenotype for natural history and interventional studies of neurodegenerative and other disorders.

“So if you’re going fossil hunting, that’s where you should look”

Abstract Whether directed at adults or children, popularization can be viewed as a process of “translating” and “recontextualizing” expert discourse for a lay audience. In fact, knowledge dissemination for children appears to entail an additional form of “translation,” given their limited background knowledge. This “re-translation” often occurs on dedicated websites based on “edutainment.” While most museum websites function as promotional tools or as agents of knowledge dissemination, a small number of them are targeted at children and offer texts that insert museum objects in a broader context. By means of a small case study, this paper explores how knowledge is popularized and presented in two science museum websites: the Natural History Museum (NHM) in London and OLogy, the science website for children of the American Museum of Natural History (AMNH) in New York. From a corpus-linguistic and discourse-analysis perspective, our interest lies in how popularization takes shape in these two websites, the former intended for different age groups and the latter explicitly addressing children. Quantitative and qualitative results show similarities and dissimilarities, thus accounting for different types of popularization as forms of translation. The analysis aims to grant insights to translators and interpreters engaged in museum adaptations and translation of contexts.

Mini Review] Global Burden and Evolving Understanding of Hepatitis E Virus

Hepatitis E virus (HEV) is the leading cause of acute viral hepatitis worldwide, recognized as a significant global public health concern. Recent advancements in understanding the natural history of HEV infection have shed light on its epidemiology and clinical implications. The primary mode of HEV transmission is fecal-oral, occurring through contaminated water or food. Parenteral transmission, particularly through blood transfusions, was initially overlooked but has been increasingly recognized in both developing and industrialized countries. Acute HEV infection typically manifests as self-limiting jaundice, particularly in immunocompetent individuals. However, recent data suggest that acute infection can progress to a chronic form in various immunosuppressive conditions, including solid organ transplantation, hematological malignancies, and human immunodeficiency virus (HIV) infection. Chronic HEV can lead to cirrhosis, which may progress rapidly in some cases. Extrahepatic manifestations, particularly neurological complications, have also been reported. HEV remains underdiagnosed globally due to a lack of awareness among healthcare providers in many regions. Advances in serological and molecular assays have facilitated reliable diagnosis, both in immunocompetent and immunocompromised patients. Ribavirin monotherapy has proven effective in treating chronic HEV infection in immunosuppressed individuals and is currently widely recommended. However, its efficacy in acute HEV remains inconclusive. In 2011, an effective and well-tolerated HEV vaccine was developed and approved in China. This vaccine holds promise for high-risk populations, particularly individuals with cirrhosis and travelers to endemic regions.

Black Lifeworlds: Poetic Black Geographies and Ecologies

The two poems that are submitted collectively as “Black Lifeworlds” are interventions in nature-society discussions. They are specifically concerned with the radical challenge that Black Geographies and Black Ecologies make vis-a-vis scholarship and discourse that are silent on the role of race in the production of space and nature. The first poem challenges racial discourses that relegate antiblackness to the colonial and antebellum period compared to a post-racist present. Through allusion to the Great Migration, the poem traces the agitations of Black mobilities. The second poem responds to the racist ecology and natural history of a European Union official, who lamenting migrants as threats to a sublime Europe, described the non-European world as a jungle. The second poem offers a counter-environmental history that rebukes European amnesia about colonial ecological violence.

Unravelling the acute respiratory infection landscape: virus type, viral load, health status and coinfection do matter

IntroductionAcute respiratory infections (ARI) are the most common infections in the general population and are mainly caused by respiratory viruses. Detecting several viruses in a respiratory sample is common. To better understand these viral codetections and potential interferences, we tested for the presence of viruses and developed quantitative PCR (Polymerase Chain Reaction) for the viruses most prevalent in coinfections: human rhinovirus (HRV) and respiratory syncytial virus (RSV), and quantified their viral loads according to coinfections and health status, age, cellular abundance and other variables.Materials and methodsSamples from two different cohorts were analyzed: one included hospitalized infants under 12 months of age with acute bronchiolitis (n=719) and the other primary care patients of all ages with symptoms of ARI (n=685). We performed Multiplex PCR on nasopharyngeal swabs, and quantitative PCR on samples positive for HRV or/and RSV to determine viral loads (VL). Cellular abundance (CA) was also estimated by qPCR targeting the GAPDH gene. Genotyping was performed either directly from first-line molecular panel or by PCR and sequencing for HRV.ResultsThe risks of viral codetection were 4.1 (IC95[1.8; 10.0]) and 93.9 1 (IC95[48.7; 190.7]) higher in infants hospitalized for bronchiolitis than in infants in primary care for RSV and HRV respectively (p<0.001). CA was higher in samples positive for multiple viruses than in mono-infected or negative samples (p<0.001), and higher in samples positive for RSV (p<0.001) and HRV (p<0.001) than in negative samples. We found a positive correlation between CA and VL for both RSV and HRV. HRV VL was higher in children than in the elderly (p<0.05), but not RSV VL. HRV VL was higher when detected alone than in samples coinfected with RSV-A and with RSV-B. There was a significant increase of RSV-A VL when codetecting with HRV (p=0.001) and when co-detecting with RSV-B+HRV versus RSV-A+ RSV-B (p=0.02).ConclusionsMany parameters influence the natural history of respiratory viral infections, and quantifying respiratory viral loads can help disentangle their contributions to viral outcome.

The bright side of the moon: vocal activity of the Black-banded owl (Strix huhula huhula) in the Yungas Andean forests of Argentina

ABSTRACT In recent years, passive acoustic monitoring (PAM) has become one of the main tools for natural history and behavior studies in nocturnal birds. In this study, we explored the Black-banded owl (Strix huhula huhula) vocal activity in the Yungas Andean forests from northwestern Argentina, using one autonomous recording unit from September 2017 to February 2018. We found higher vocal activity on nights with high lunar illumination (76–100%), mainly concentrated during the early night: between 22:00–23:00 h; approximately 1–2 hours after sunset. This study shows the first acoustic phenology pattern of the black-banded owl during a year-round survey with the use of PAM in the Yungas. We highlight the importance of this type of research to gain knowledge on the vocal behavior of Neotropical nocturnal birds. Additionally we highlight the necessity of incorporating PAM, combined with occupation models, to evaluate the population status of threatened nocturnal bird species.

Cardiovascular Burden of the V142I Transthyretin Variant.

Individual cohort studies concur that the amyloidogenic V142I variant of the transthyretin (TTR) gene, present in 3% to 4% of US Black individuals, increases heart failure (HF) and mortality risk. Precisely defining carrier risk across relevant clinical outcomes and estimating population burden of disease are important given established and emerging targeted treatments. To better define the natural history of disease in carriers across mid to late life, assess variant modifiers, and estimate cardiovascular burden to the US population. A total of 23 338 self-reported Black participants initially free from HF were included in 4 large observational studies across the US (mean [SD], 15.5 [8.2] years of follow-up). Data analysis was performed between May 2023 and February 2024. V142I carrier status (n = 754, 3.2%). Hospitalizations for HF (including subtypes of reduced and preserved ejection fraction) and all-cause mortality. Outcomes were analyzed by generating 10-year hazard ratios for each age between 50 and 90 years. Using actuarial methods, mean survival by carrier status was estimated and applied to the 2022 US population using US Census data. Among the 23 338 participants, the mean (SD) age at baseline was 62 (9) years and 76.7% were women. Ten-year carrier risk increased for HF hospitalization by age 63 years, predominantly driven by HF with reduced ejection fraction, and 10-year all-cause mortality risk increased by age 72 years. Only age (but not sex or other select variables) modified risk with the variant, with estimated reductions in longevity ranging from 1.9 years (95% CI, 0.6-3.1) at age 50 to 2.8 years (95% CI, 2.0-3.6) at age 81. Based on these data, 435 851 estimated US Black carriers between ages 50 and 95 years are projected to cumulatively lose 957 505 years of life (95% CI, 534 475-1 380 535) due to the variant. Among self-reported Black individuals, male and female V142I carriers faced similar and substantial risk for HF hospitalization, predominantly with reduced ejection fraction, and death, with steep age-dependent penetrance. Delineating the individual contributions of, and complex interplay among, the V142I variant, ancestry, the social construct of race, and biological or social determinants of health to cardiovascular disease merits further investigation.

Hepatocellular carcinoma surveillance after HBsAg seroclearance

Hepatitis B surface antigen (HBsAg) seroclearance is considered the functional cure and the optimal treatment endpoint for chronic hepatitis B (CHB). Patients with CHB who cleared HBsAg generally have a favorable clinical course with minimal risk of developing hepatocellular carcinoma (HCC) or cirrhotic complications. Nevertheless, a minority of patients still develop HCC despite HBsAg seroclearance. While patients with liver cirrhosis are still recommended for HCC surveillance, whether other non-cirrhotic patients who achieved HBsAg seroclearance should remain on HCC surveillance remains unclear. This review provides an overview of the incidence of HBsAg seroclearance, the factors associated with the occurrence of HBsAg seroclearance, the durability of HBsAg seroclearance, the risk of developing HCC after HBsAg seroclearance, the risk factors associated with HCC development after HBsAg seroclearance, the role of HCC risk scores, and the implications on HCC surveillance. Existing HCC risk scores have a reasonably good performance in patients after HBsAg seroclearance. In the era of artificial intelligence, future HCC risk prediction models based on artificial intelligence and longitudinal clinical data may further improve the prediction accuracy to establish a foundation of a risk score-based HCC surveillance strategy. As different novel hepatitis B virus (HBV) antiviral agents aiming at HBsAg seroclearance are under active development, new knowledge is anticipated on the natural history and HCC risk prediction of patients treated with new HBV drugs.

Science in the service of politics. The cartographic representation of a local territorial context of the Kingdom of Naples in the early nineteenth century

The erudite priest Marciano Di Leo (1751–1819), a prominent personality in the historical and geographical panorama of his time, not only in his home territory, authored a vast literary and poetic production, but also tried his hand at producing some maps, referring to a province of the Kingdom of Naples. At a time when the principles of geodetic cartography had become increasingly known, even locally, hand in hand with improvements in technology and accuracy of measurements, the author reflects the historical narratives of progress of the European (and Neapolitan) Enlightenment and translates them into an unpublished manuscript of statistical, historical, and geographical nature, accompanied by numerous maps of various scales. The rediscovery of a largely unknown—and therefore not very thorough—minor cartographic production underscores the spread even in more marginal contexts of the most innovative ideas and increasingly precise scientific foundations in the cartographic-mathematical representation of the territory. It also illustrates the role of a number of intellectuals in the service of the political choices of their time, in an attempt-often unrealized-to bring about a decisive change of course in public administration, in accordance with Enlightenment ideals and in the spirit of reform that spread throughout Europe thanks to the French Revolution.

TUBERCULOSIS OF THE WRIST

INTRODUCTIONTuberculosis (TB) is a public health challenge. However, musculoskeletal involvement represents 10–15% of all extrapulmonary cases. Upper extremity involvement is extremely rare. The slow progressive course of clinical symptoms and lack of radiological signs lead to difficulties in establishing early diagnosis. Hence, the patients who have tuberculosis of the wrist are usually misdiagnosed. We report 5 cases of tuberculosis of the wrist seen in our unit from the year 2012 to 2021.METHODSCases were retrospectively evaluated on demographics, nature of history, clinical presentation, culture finding, and histopathological findings from 2012 to 2021 at our unit.RESULTSA total of 5 cases were evaluated retrospectively. Three patients were more than 60 years old and two were less than 30 years old. Four of the patients presented with wrist swelling 2 of them had wrist pain and only 1 patient had discharge from the wound. The duration of the symptoms ranges from 2 months to 3 years. Only one of the patients had a history of pulmonary TB contact whereas the others didn't. All patients underwent surgery. All of the patients had positive cultures for Mycobacterium tuberculosis complex and histopathological examination showed necrotizing granulomatous inflammation from specimens taken intraoperatively, which confirmed the diagnosis of tuberculosis of the wrist.DISCUSSIONSOur cases show that the common presentation of tuberculosis of the wrist was comparable to other literature. Most of the patients presented with chronic wrist swelling with or without wrist pain. The diagnosis of the disease was delayed an average of 10 - 12 months from symptoms onset to diagnosis. S. Bayram et al reported a case where the diagnosis was made 45 months later. Due to its rarity, it often is misdiagnosed, resulting in delays in the proper treatment.CONCLUSIONThe diagnosis of the TB wrist remains difficult because of insidious and non-specific. presentation. However, early diagnosis is essential to avoid delays in treatment and complications. Hence, chronic wrist pain, and swelling with or without unexplained bone erosion around the wrist area must be highly suspected of being osteoarticular tuberculosis.

One Hundred and Thirty-Five Years of Ornithology in Bulgaria: The Role of the National Museum of Natural History at the Bulgarian Academy of Sciences in the Development of Ornithology in Bulgaria—Representatives, Collections and Achievements

For the first time, an attempt has been made to present, chronologically and in a systematized form, the development of ornithological studies at the National Museum of Natural History in Sofia (Bulgaria) from its foundation in the last decades of the 19th century to the present day. This 135-year period (1889–2024) includes the work of 12 curators of the ornithological collections. Their major contributions and most-significant ornithological publications are also presented.

On three species of the genus Habrocestum Simon, 1876 (Araneae: Salticidae: Hasariini) from India

Two new species of the ground-dwelling jumping spider genus Habrocestum Simon, 1876 from the wet evergreen forests of the southern Western Ghats, India are described: H. benjamin sp. nov. (♂♀) and H. swaminathan sp. nov. (♂♀). Furthermore, H. emanasakgrensis Kadam & Tripathi, 2023 is synonymized with Chinattus validus (Xie, Peng & Kim, 1993) syn. nov.. Diagnoses, digital illustrations, morphological descriptions, natural history notes and discussion are provided.

Beyond access: (re)designing archival guides for changing landscapes

AbstractIn 2013, the authors of this article and their colleague Gavan McCarthy published Stories in Stone: an annotated history and guide to the collections of Ernest Westlake (1855–1922). The guide provided contextual information and digital access to the entire paper archives relating to the three large stone collections formed by Westlake during his lifetime: French and English geological specimens housed in the Oxford University Museum of Natural History from 1924, and a collection of Tasmanian Aboriginal stone tools stored in the Pitt Rivers Museum since 1923. The Tasmanian collections, formed by Westlake from 1908 to 1910, are highly significant to the Palawa (or Pakana or Tasmanian Aboriginal) community because they include objects made by ancestors, and words spoken by ancestors to Westlake and recorded in his field notebooks. Stories in Stone was created to improve access to Westlake’s Tasmanian collections for the Palawa community with whom author Rebe Taylor had worked closely since 1999. Nonetheless, the structural and technical design of Stories in Stone was not Palawa-led. It was driven by Australian and international archiving standards; by stipulations set out by the collecting institutions; and by the stories of collecting and subsequent scholarship on the collections. In 2023, Stories in Stone is offline, and the authors are planning a relaunch. This time they aim to reach beyond their original aim of providing archival access to the Palawa community, and work with Palawa community to co-design how that access is delivered. This consultative work will be done at the University of Tasmania, where Palawa advisors and other Indigenous scholars have been integral to developing international Indigenous data sovereignty principals. This article precedes those formal discussions and thus offers a timely reflection on the original aims and design of Stories in Stone as well as an extensive analysis of broader changes in the management and dissemination of First Nations collections and culture. Such changes include: international human rights frameworks; movements supporting data and archival sovereignty; co-designed archival technologies; and increased focus on archives as process not merely product. These developments will lay the foundations for the next version of Stories in Stone, which aims to go beyond access, scholarship, and standards by helping to facilitate First Nations’ aspirations for dignity, sovereignty, and self-determination.

Clinical, genetic, and cognitive correlates of seizure occurrences in Phelan-McDermid syndrome

BackgroundPhelan-McDermid syndrome (PMS) is a genetic neurodevelopmental disorder caused by SHANK3 haploinsufficiency and is associated with an increased risk for seizures. Previous literature indicates that around one third of individuals with PMS also have epilepsy or seizures, with a wide range of types and ages of onset. Investigating the impact of seizures on intellectual and adaptive functioning for PMS is a primary concern for caregivers and is important to understanding the natural history of this syndrome.MethodsWe report on results from 98 individuals enrolled in a prospective, longitudinal study. We detailed seizure frequency, type, and age of onset, and we analyzed seizure occurrence with best estimate IQ, adaptive functioning, clinical features, and genotype. We conducted multiple linear regression analyses to assess the relationship between the presence of seizures and the Vineland Adaptive Behavior Scale, Second Edition (VABS-II) Adaptive Behavior Composite score and the best estimate full-scale IQ. We also performed Chi-square tests to explore associations between seizure prevalence and genetic groupings. Finally, we performed Chi-square tests and t-tests to explore the relationship between seizures and demographic features, features that manifest in infancy, and medical features.ResultsSeizures were present in 41% of the cohort, and age of onset was widely variable. The presence of seizures was associated with significantly lower adaptive and intellectual functioning. Genotype–phenotype analyses were discrepant, with no differences in seizure prevalence across genetic classes, but with more genes included in deletions of participants with 22q13 deletions and seizures compared to those with 22q13 deletions and no seizures. No clinical associations were found between the presence of seizures and sex, history of pre- or neonatal complications, early infancy, or medical features. In this cohort, generalized seizures were associated with developmental regression, which is a top concern for PMS caregivers.ConclusionsThese results begin to eludicate correlates of seizures in individuals with PMS and highlight the importance of early seizure management. Importantly, presence of seizures was associated with adaptive and cognitive functioning. A larger cohort might be able to identify additional associations with medical features. Genetic findings suggest an increased capability to realize genotype–phenotype relationships when deletion size is taken into account.

Electroencephalographic Correlates of Clinical Severity in the Natural history study of RTT and Related Disorders.

This study was undertaken to characterize quantitative electroencephalographic (EEG) features in participants from the Natural history study of RTT and Related Disorders and to assess the potential for these features to act as objective measures of cortical function for Rett syndrome (RTT). EEG amplitude and power features were derived from the resting EEG of 60 females with RTT (median age = 10.7 years) and 26 neurotypical females (median age = 10.6 years). Analyses focus on group differences and within the RTT group, associations between the EEG parameters and clinical severity. For a subset of participants (n = 20), follow-up data were available for assessing the reproducibility of the results and the stability in the parameters over 1 year. Compared to neurotypical participants, participants with RTT had greater amplitude variability and greater low-frequency activity as reflected by greater delta power, more negative 1/f slope, and lower theta/delta, alpha/delta, beta/delta, alpha/theta, and beta/theta ratios. Greater delta power, more negative 1/f slope, and lower power ratios were associated with greater severity. Analyses of year 1 data replicated the associations between 1/f slope and power ratios and clinical severity and demonstrated good within-subject consistency in these measures. Overall, group comparisons reflected a greater predominance of lower versus higher frequency activity in participants with RTT, which is consistent with prior clinical interpretations of resting EEG in this population. The observed associations between the EEG power measures and clinical assessments and the repeatability of these measures underscore the potential for EEG to provide an objective measure of cortical function and clinical severity for RTT. ANN NEUROL 2024.