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IntroductionAlthough frontotemporal dementia (FTD) with right anterior temporal lobe (RATL) predominance has been recognized, a uniform description of the syndrome is still missing. This multicenter study aims to establish a cohesive clinical phenotype.MethodsRetrospective clinical data from 18 centers across 12 countries yielded 360 FTD patients with predominant RATL atrophy through initial neuroimaging assessments.ResultsCommon symptoms included mental rigidity/preoccupations (78%), disinhibition/socially inappropriate behavior (74%), naming/word-finding difficulties (70%), memory deficits (67%), apathy (65%), loss of empathy (65%), and face-recognition deficits (60%). Real-life examples unveiled impairments regarding landmarks, smells, sounds, tastes, and bodily sensations (74%). Cognitive test scores indicated deficits in emotion, people, social interactions, and visual semantics however, lacked objective assessments for mental rigidity and preoccupations.DiscussionThis study cumulates the largest RATL cohort unveiling unique RATL symptoms subdued in prior diagnostic guidelines. Our novel approach, combining real-life examples with cognitive tests, offers clinicians a comprehensive toolkit for managing these patients.HighlightsThis project is the first international collaboration and largest reported cohort. Further efforts are warranted for precise nomenclature reflecting neural mechanisms. Our results will serve as a clinical guideline for early and accurate diagnoses.

With the emergence of Alzheimer's disease (AD) disease-modifying therapies, identifying patients who could benefit from these treatments becomes critical. In this study, we evaluated whether a precise blood test could perform as well as established cerebrospinal fluid (CSF) tests in detecting amyloid-β (Aβ) plaques and tau tangles. Plasma %p-tau217 (ratio of phosporylated-tau217 to non-phosphorylated tau) was analyzed by mass spectrometry in the Swedish BioFINDER-2 cohort (n = 1,422) and the US Charles F. and Joanne Knight Alzheimer Disease Research Center (Knight ADRC) cohort (n = 337). Matched CSF samples were analyzed with clinically used and FDA-approved automated immunoassays for Aβ42/40 and p-tau181/Aβ42. The primary and secondary outcomes were detection of brain Aβ or tau pathology, respectively, using positron emission tomography (PET) imaging as the reference standard. Main analyses were focused on individuals with cognitive impairment (mild cognitive impairment and mild dementia), which is the target population for available disease-modifying treatments. Plasma %p-tau217 was clinically equivalent to FDA-approved CSF tests in classifying Aβ PET status, with an area under the curve (AUC) for both between 0.95 and 0.97. Plasma %p-tau217 was generally superior to CSF tests in classification of tau-PET with AUCs of 0.95-0.98. In cognitively impaired subcohorts (BioFINDER-2: n = 720; Knight ADRC: n = 50), plasma %p-tau217 had an accuracy, a positive predictive value and a negative predictive value of 89-90% for Aβ PET and 87-88% for tau PET status, which was clinically equivalent to CSF tests, further improving to 95% using a two-cutoffs approach. Blood plasma %p-tau217 demonstrated performance that was clinically equivalent or superior to clinically used FDA-approved CSF tests in the detection of AD pathology. Use of high-performance blood tests in clinical practice can improve access to accurate AD diagnosis and AD-specific treatments.

This paper describes and evaluates student teachers' virtual simulation training on teaching a controversial issue. In the fourth year of their program to become social science teachers at lower and upper secondary schools, 43 student teachers in Sweden conducted simulation teaching on conspiracy theories as an example of a controversial issue. Conspiracy theories appeal to young people and they often encounter these theories online, but they can be met with increased knowledge about how conspiracy theories work, and how they can be identified and countered. Thus, students at primary and secondary school need to develop their critical source skills. The Swedish Schools Inspectorate (2022) found that these issues were not properly taught because they were not connected to schools' values-based work or to the development of students' democratic competence. To analyze the simulation teaching, data was collected through observations, video-recorded simulation teaching, interviews with student teachers, and reflective documents. The results show that simulation teaching offers student teachers the opportunity to integrate content knowledge, pedagogical content knowledge, and subject knowledge, by being trained to become flexible and responsive to avatars' individual differences as well as their different attitudes and understanding of the subject.

IntroductionThe pace of innovation has accelerated in virtually every area of tau research in just the past few years.MethodsIn February 2022, leading international tau experts convened to share selected highlights of this work during Tau 2022, the second international tau conference co-organized and co-sponsored by the Alzheimer's Association, CurePSP, and the Rainwater Charitable Foundation.ResultsRepresenting academia, industry, and the philanthropic sector, presenters joined more than 1700 registered attendees from 59 countries, spanning six continents, to share recent advances and exciting new directions in tau research.DiscussionThe virtual meeting provided an opportunity to foster cross-sector collaboration and partnerships as well as a forum for updating colleagues on research-advancing tools and programs that are steadily moving the field forward.

T cells are critical for immune protection against severe COVID-19, but it has remained unclear whether repeated exposure to SARS-CoV-2 antigens delivered in the context of vaccination fuels T cell exhaustion or reshapes T cell functionality. Here, we sampled convalescent donors with a history of mild or severe COVID-19 before and after SARS-CoV-2 vaccination to profile the functional spectrum of hybrid T cell immunity. Using combined single-cell technologies and high-dimensional flow cytometry, we found that the frequencies and functional capabilities of spike-specific CD4+ and CD8+ T cells in previously infected individuals were enhanced by vaccination, despite concomitant increases in the expression of inhibitory receptors such as PD-1 and TIM3. In contrast, CD4+ and CD8+ T cells targeting non-spike proteins remained functionally static and waned over time, and only minimal effects were observed in healthy vaccinated donors experiencing breakthrough infections with SARS-CoV-2. Moreover, hybrid immunity was characterized by elevated expression of IFN-γ, which was linked with clonotype specificity in the CD8+ T cell lineage. Collectively, these findings identify a molecular hallmark of hybrid immunity and suggest that vaccination after infection is associated with cumulative immunological benefits over time, potentially conferring enhanced protection against subsequent episodes of COVID-19.

Leptomeninges, consisting of the pia mater and arachnoid, form a connective tissue investment and barrier enclosure of the brain. The exact nature of leptomeningeal cells has long been debated. In this study, we identify five molecularly distinct fibroblast-like transcriptomes in cerebral leptomeninges; link them to anatomically distinct cell types of the pia, inner arachnoid, outer arachnoid barrier, and dural border layer; and contrast them to a sixth fibroblast-like transcriptome present in the choroid plexus and median eminence. Newly identified transcriptional markers enabled molecular characterization of cell types responsible for adherence of arachnoid layers to one another and for the arachnoid barrier. These markers also proved useful in identifying the molecular features of leptomeningeal development, injury, and repair that were preserved or changed after traumatic brain injury. Together, the findings highlight the value of identifying fibroblast transcriptional subsets and their cellular locations toward advancing the understanding of leptomeningeal physiology and pathology.

Monoterpenoid indole alkaloids (MIAs) represent a large class of plant natural products with marketed pharmaceutical activities against a wide range of indications, including cancer, malaria and hypertension. Halogenated MIAs have shown improved pharmaceutical properties; however, synthesis of new-to-nature halogenated MIAs remains a challenge. Here we demonstrate a platform for de novo biosynthesis of two MIAs, serpentine and alstonine, in baker's yeast Saccharomyces cerevisiae and deploy it to systematically explore the biocatalytic potential of refactored MIA pathways for the production of halogenated MIAs. From this, we demonstrate conversion of individual haloindole derivatives to a total of 19 different new-to-nature haloserpentine and haloalstonine analogs. Furthermore, by process optimization and heterologous expression of a modified halogenase in the microbial MIA platform, we document de novo halogenation and biosynthesis of chloroalstonine. Together, this study highlights a microbial platform for enzymatic exploration and production of complex natural and new-to-nature MIAs with therapeutic potential.

Abstract Background The World Health Organization 2022 malaria chemoprevention guidelines recommend providing a full course of antimalarial treatment at pre-defined intervals, regardless of malaria status to prevent illness among children resident in moderate to high perennial malaria transmission settings as perennial malaria chemoprevention (PMC) with sulfadoxine-pyrimethamine (SP). The dhps I431V mutation circulating in West Africa has unknown effect on SP protective efficacy. Methods This protocol is for a three-arm, parallel, double-blinded, placebo-controlled, randomised trial in Cameroon among children randomly assigned to one of three directly-observed treatment groups: (i) Group 1 (n = 450) receives daily artesunate (AS) placebo on days − 7 to -1, then active SP plus placebo amodiaquine (AQ) on day 0, and placebo AQ on days 1 and 2; (ii) Group 2 (n = 250) receives placebo AS on days − 7 to -1, then active SP and AQ on day 0, and active AQ on days 1 and 2; and (iii) Group 3 (n = 200) receives active AS on days − 7 to -1, then placebo SP on day 0 and placebo AQ on days 0 to 2. On days 0, 2, 5, 7, and thereafter weekly until day 28, children provide blood for thick smear slides. Dried blood spots are collected on the same days and weekly from day 28 to day 63 for quantitative polymerase chain reaction (qPCR) and genotype analyses. Discussion Our aim is to quantify the chemopreventive efficacy of SP, and SP plus AQ, and measure the effect of the parasite genotypes associated with SP resistance on parasite clearance and protection from infection when exposed to SP chemoprevention. We will report unblinded results including: (i) time-to-parasite clearance among SP and SP plus AQ recipients who were positive on day 0 by qPCR and followed to day 63; (ii) mean duration of SP and SP plus AQ protection against infection, and (iii) mean duration of symptom-free status among SP and SP plus AQ recipients who were parasite free on day 0 by qPCR. Our study is designed to compare the 28-day follow-up of the new WHO malaria chemoprevention efficacy study protocol with extended follow-up to day 63. Trial registration ClinicalTrials.gov NCT06173206; 15/12/2023.

Abstract Identifying concomitant Lewy body (LB) pathology through seed amplification assays (SAA) might enhance the diagnostic and prognostic work-up of Alzheimer’s disease (AD) in clinical practice and trials. This study examined whether LB pathology exacerbates AD-related disease progression in 795 cognitively impaired individuals (Mild Cognitive Impairment and dementia) from the longitudinal multi-center observational ADNI cohort. Participants were on average 75 years of age (SD = 7.89), 40.8% were female, 184 (23.1%) had no biomarker evidence of AD/LB pathology, 39 (4.9%) had isolated LB pathology (AD-LB+), 395 (49.7%) had only AD pathology (AD+LB-), and 177 (22.3%) had both pathologies (AD+LB+). The AD+LB+ group showed worst baseline performance for most cognitive outcomes and compared to the AD+LB− group faster global cognitive decline and more cortical hypometabolism, particularly in posterior brain regions. Neuropathological examination (n = 61) showed high sensitivity (26/27, 96.3%) and specificity (27/28, 96.4%) of the SAA-test. We showed that co-existing LB-positivity exacerbates cognitive decline and cortical brain hypometabolism in AD. In vivo LB pathology detection could enhance prognostic evaluations in clinical practice and could have implications for clinical AD trial design.

Abstract The accelerating use of plastics worldwide is of societal concern, especially as plastics fragment into smaller, micro- and nano-sized particles. Of particular importance is the effects on aquatic ecosystems since a major part of the nanoplastics eventually reach natural water systems. We identify, using replicated experimental wetlands, a tipping point where nanoplastics become detrimental to the key planktonic grazer, Daphnia. Moreover, the phytoplankton diatoms were also strongly affected by nanoplastics, whereas we detected no effects on the less efficient herbivore copepods, cyanobacteria, benthic bacterial decomposition or any bottom dwelling organisms. That some organisms and ecosystem functions, but not others, are strongly affected by nanoplastic particles predicts considerable alterations in aquatic food webs and a rewiring of feeding links. In a broader context, our study provides crucial data on the effects of nanoplastics in freshwater ecosystems, constituting urgently needed understanding for risk assessment, legislation, and management of plastic material.

To explore the effect of lactation stage and parity on the milking order of cows, we collected milking order data of all lactating cows (n = 251) over a period of 12 wk in one commercial Swedish dairy cow herd using a herringbone milking parlor. Cows were kept in 2 housing groups (G1 and G2) and moved from G1 to G2 at approximately mid lactation. Two analyses were conducted to investigate if lactation stage (early: 2–49 d in milk, mid: 50–179 d in milk, and late ≥180 d in milk) and parity are associated with the entrance order to the parlor or a preference of entering a new milking line first. In G1 and G2, cows in first parity entered the milking parlor earlier than cows in higher parities. In addition, in G1 cows in early lactation entered the milking parlor earlier than cows in later lactation. Similar effects were observed for the preference of entering a new milking line first. No effect of mid versus late lactation could be observed in either G1 or G2. The study also found that cows tend to keep their rank within the milking order constant. The results of the study indicate that cows of presumably lower hierarchy (first parity and early lactation) leave the waiting area earlier compared with other cows. This should be considered when planning grouping strategies and preventive measures against mastitis pathogen transmission.

Abstract Background The Nova Scotia Duck Tolling Retriever (NSDTR) has previously been highlighted as a breed at risk for developing immune mediated diseases and cancer. The immune response is of great importance for the development of neoplastic disease and a dysregulated immune response may predispose to cancer. Two of the commonly seen immune mediated diseases in NSDTRs are immune mediated rheumatic disease (IMRD), which bears similarities to systemic lupus erythematosus (SLE) affecting humans, and steroid-responsive meningitis-arteritis (SRMA), which is a non-infectious inflammation of the meninges and the leptomeningeal vessels. The aim of this survey study was to investigate the lifetime prevalence of immune mediated diseases and tumors among Swedish NSDTRs based on owners’ information. The study design was cross-sectional. A questionnaire was sent to 4102 persons who owned or had previously owned a NSDTR. The questions concerned information about the dog and its overall health status as well as specific diseases. Results The response rate was 30%, including 935 live NSDTRs, corresponding to approximately 20% of the current population registered in Sweden (n = 4564), and 177 dead dogs. The surveyed dogs were spread over different ages and sex and corresponded to the typical demographic profile of the general dog population. Of the 935 individuals that were alive, 28 dogs (3%) were reported as previously diagnosed with IMRD and 33 dogs (3.5%) were reported as previously diagnosed with SRMA, one dog was reported to have been diagnosed with both SRMA and IMRD. There were 129 dogs (14%) reported to have or have had a neoplasia of some kind. For the dead dogs (n = 177), almost 40% of the owners reported neoplasia as the main reason for death/euthanasia. Conclusion This study reports an estimated lifetime prevalence of IMRD and SRMA, in the studied population of Swedish NSDTRs, of 3.0 and 3.5% respectively. In this study, 14% of the living dogs (n = 935) were reported to have a neoplasia of some kind and almost 40% of the deceased dogs (n = 177) were euthanized due to neoplasia or suspicion of it.