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arch The archaeologist fighting claims about an advanced lost civilisation By www.newscientist.com Published On :: Mon, 14 Oct 2024 17:00:00 +0100 Netflix’s Ancient Apocalypse peddles the idea that we have overlooked an extraordinary ancient civilisation. Flint Dibble explains why that is wrong, and why real archaeology is more exciting Full Article
arch Claudia de Rham: In search of the true nature of gravity By www.newscientist.com Published On :: Thu, 28 Mar 2024 08:00:14 +0000 Claudia de Rham has spent much of her life dedicated to unravelling the true nature of gravity, thinking deeply about gravitons, the hypothetical carrier of this enigmatic force Full Article
arch The physicist searching for quantum gravity in gravitational rainbows By www.newscientist.com Published On :: Tue, 26 Mar 2024 16:00:00 +0000 Claudia de Rham thinks that gravitons, hypothetical particles thought to carry gravity, have mass. If she’s right, we can expect to see “rainbows” in ripples in space-time Full Article
arch Dazzling images illuminate research on cardiovascular disease By www.newscientist.com Published On :: Tue, 05 Nov 2024 15:00:25 +0000 The British Heart Foundation’s Reflections of Research competition showcases beautiful images captured by researchers studying heart and circulatory disease Full Article
arch The archaeologist fighting claims about an advanced lost civilisation By www.newscientist.com Published On :: Mon, 14 Oct 2024 17:00:00 +0100 Netflix’s Ancient Apocalypse peddles the idea that we have overlooked an extraordinary ancient civilisation. Flint Dibble explains why that is wrong, and why real archaeology is more exciting Full Article
arch Scientists Dismayed by Stem Cell Research Ruling By www.medicinenet.com Published On :: Mon, 29 Aug 2022 00:00:00 PDT Title: Scientists Dismayed by Stem Cell Research RulingCategory: Health NewsCreated: 8/24/2010 2:10:00 PMLast Editorial Review: 8/25/2010 12:00:00 AM Full Article
arch Quality of Pain Counts as Much as Intensity, Researchers Say By www.medicinenet.com Published On :: Mon, 29 Aug 2022 00:00:00 PDT Title: Quality of Pain Counts as Much as Intensity, Researchers SayCategory: Health NewsCreated: 8/26/2010 4:10:00 PMLast Editorial Review: 8/27/2010 12:00:00 AM Full Article
arch Brain Bleeds More Common in Smokers, Research Shows By www.medicinenet.com Published On :: Mon, 29 Aug 2022 00:00:00 PDT Title: Brain Bleeds More Common in Smokers, Research ShowsCategory: Health NewsCreated: 8/30/2012 10:05:00 AMLast Editorial Review: 8/30/2012 12:00:00 AM Full Article
arch Gene Research Yields Insights Into Ebola Virus By www.medicinenet.com Published On :: Mon, 29 Aug 2022 00:00:00 PDT Title: Gene Research Yields Insights Into Ebola VirusCategory: Health NewsCreated: 8/28/2014 2:36:00 PMLast Editorial Review: 8/29/2014 12:00:00 AM Full Article
arch Animal Research Yields Clues to Sexual Spread of Zika By www.medicinenet.com Published On :: Mon, 29 Aug 2022 00:00:00 PDT Title: Animal Research Yields Clues to Sexual Spread of ZikaCategory: Health NewsCreated: 8/25/2016 12:00:00 AMLast Editorial Review: 8/26/2016 12:00:00 AM Full Article
arch Search for Coronavirus Origins at Standstill: WHO Team By www.medicinenet.com Published On :: Mon, 29 Aug 2022 00:00:00 PDT Title: Search for Coronavirus Origins at Standstill: WHO TeamCategory: Health NewsCreated: 8/26/2021 12:00:00 AMLast Editorial Review: 8/26/2021 12:00:00 AM Full Article
arch There's More MS in Northern Countries. Now, Researchers Find New Reason Why By www.medicinenet.com Published On :: Thu, 25 Aug 2022 00:00:00 PDT Title: There's More MS in Northern Countries. Now, Researchers Find New Reason WhyCategory: Health NewsCreated: 8/25/2022 12:00:00 AMLast Editorial Review: 8/25/2022 12:00:00 AM Full Article
arch Complete genomes of Asgard archaea reveal diverse integrated and mobile genetic elements [RESEARCH] By genome.cshlp.org Published On :: 2024-10-29T06:46:08-07:00 Asgard archaea are of great interest as the progenitors of Eukaryotes, but little is known about the mobile genetic elements (MGEs) that may shape their ongoing evolution. Here, we describe MGEs that replicate in Atabeyarchaeia, a wetland Asgard archaea lineage represented by two complete genomes. We used soil depth–resolved population metagenomic data sets to track 18 MGEs for which genome structures were defined and precise chromosome integration sites could be identified for confident host linkage. Additionally, we identified a complete 20.67 kbp circular plasmid and two family-level groups of viruses linked to Atabeyarchaeia, via CRISPR spacer targeting. Closely related 40 kbp viruses possess a hypervariable genomic region encoding combinations of specific genes for small cysteine-rich proteins structurally similar to restriction-homing endonucleases. One 10.9 kbp integrative conjugative element (ICE) integrates genomically into the Atabeyarchaeum deiterrae-1 chromosome and has a 2.5 kbp circularizable element integrated within it. The 10.9 kbp ICE encodes an expressed Type IIG restriction-modification system with a sequence specificity matching an active methylation motif identified by Pacific Biosciences (PacBio) high-accuracy long-read (HiFi) metagenomic sequencing. Restriction-modification of Atabeyarchaeia differs from that of another coexisting Asgard archaea, Freyarchaeia, which has few identified MGEs but possesses diverse defense mechanisms, including DISARM and Hachiman, not found in Atabeyarchaeia. Overall, defense systems and methylation mechanisms of Asgard archaea likely modulate their interactions with MGEs, and integration/excision and copy number variation of MGEs in turn enable host genetic versatility. Full Article
arch Global characterization of somatic mutations and DNA methylation changes during vegetative propagation in strawberries [RESEARCH] By genome.cshlp.org Published On :: 2024-10-29T06:46:07-07:00 Somatic mutations arise and accumulate during tissue culture and vegetative propagation, potentially affecting various traits in horticultural crops, but their characteristics are still unclear. Here, somatic mutations in regenerated woodland strawberry derived from tissue culture of shoot tips under different conditions and 12 cultivated strawberry individuals are analyzed by whole genome sequencing. The mutation frequency of single nucleotide variants is significantly increased with increased hormone levels or prolonged culture time in the range of 3.3 x 10–8–3.0 x 10–6 mutations per site. CG methylation shows a stable reduction (0.71%–8.03%) in regenerated plants, and hypoCG-DMRs are more heritable after sexual reproduction. A high-quality haplotype-resolved genome is assembled for the strawberry cultivar "Beni hoppe." The 12 "Beni hoppe" individuals randomly selected from different locations show 4731–6005 mutations relative to the reference genome, and the mutation frequency varies among the subgenomes. Our study has systematically characterized the genetic and epigenetic variants in regenerated woodland strawberry plants and different individuals of the same strawberry cultivar, providing an accurate assessment of somatic mutations at the genomic scale and nucleotide resolution in plants. Full Article
arch Evolutionary dynamics of polyadenylation signals and their recognition strategies in protists [RESEARCH] By genome.cshlp.org Published On :: 2024-10-29T06:46:07-07:00 The poly(A) signal, together with auxiliary elements, directs cleavage of a pre-mRNA and thus determines the 3' end of the mature transcript. In many species, including humans, the poly(A) signal is an AAUAAA hexamer, but we recently found that the deeply branching eukaryote Giardia lamblia uses a distinct hexamer (AGURAA) and lacks any known auxiliary elements. Our discovery prompted us to explore the evolutionary dynamics of poly(A) signals and auxiliary elements in the eukaryotic kingdom. We use direct RNA sequencing to determine poly(A) signals for four protists within the Metamonada clade (which also contains G. lamblia) and two outgroup protists. These experiments reveal that the AAUAAA hexamer serves as the poly(A) signal in at least four different eukaryotic clades, indicating that it is likely the ancestral signal, whereas the unusual Giardia version is derived. We find that the use and relative strengths of auxiliary elements are also plastic; in fact, within Metamonada, species like G. lamblia make use of a previously unrecognized auxiliary element where nucleotides flanking the poly(A) signal itself specify genuine cleavage sites. Thus, despite the fundamental nature of pre-mRNA cleavage for the expression of all protein-coding genes, the motifs controlling this process are dynamic on evolutionary timescales, providing motivation for future biochemical and structural studies as well as new therapeutic angles to target eukaryotic pathogens. Full Article
arch De novo genome assemblies of two cryptodiran turtles with ZZ/ZW and XX/XY sex chromosomes provide insights into patterns of genome reshuffling and uncover novel 3D genome folding in amniotes [RESEARCH] By genome.cshlp.org Published On :: 2024-10-29T06:46:07-07:00 Understanding the evolution of chromatin conformation among species is fundamental to elucidate the architecture and plasticity of genomes. Nonrandom interactions of linearly distant loci regulate gene function in species-specific patterns, affecting genome function, evolution, and, ultimately, speciation. Yet, data from nonmodel organisms are scarce. To capture the macroevolutionary diversity of vertebrate chromatin conformation, here we generate de novo genome assemblies for two cryptodiran (hidden-neck) turtles via Illumina sequencing, chromosome conformation capture, and RNA-seq: Apalone spinifera (ZZ/ZW, 2n = 66) and Staurotypus triporcatus (XX/XY, 2n = 54). We detected differences in the three-dimensional (3D) chromatin structure in turtles compared to other amniotes beyond the fusion/fission events detected in the linear genomes. Namely, whole-genome comparisons revealed distinct trends of chromosome rearrangements in turtles: (1) a low rate of genome reshuffling in Apalone (Trionychidae) whose karyotype is highly conserved when compared to chicken (likely ancestral for turtles), and (2) a moderate rate of fusions/fissions in Staurotypus (Kinosternidae) and Trachemys scripta (Emydidae). Furthermore, we identified a chromosome folding pattern that enables "centromere–telomere interactions" previously undetected in turtles. The combined turtle pattern of "centromere–telomere interactions" (discovered here) plus "centromere clustering" (previously reported in sauropsids) is novel for amniotes and it counters previous hypotheses about amniote 3D chromatin structure. We hypothesize that the divergent pattern found in turtles originated from an amniote ancestral state defined by a nuclear configuration with extensive associations among microchromosomes that were preserved upon the reshuffling of the linear genome. Full Article
arch Mutational scanning of CRX classifies clinical variants and reveals biochemical properties of the transcriptional effector domain [RESEARCH] By genome.cshlp.org Published On :: 2024-10-29T06:46:07-07:00 The transcription factor (TF) cone-rod homeobox (CRX) is essential for the differentiation and maintenance of photoreceptor cell identity. Several human CRX variants cause degenerative retinopathies, but most are variants of uncertain significance. We performed a deep mutational scan (DMS) of nearly all possible single amino acid substitutions in CRX using a cell-based transcriptional reporter assay, curating a high-confidence list of nearly 2000 variants with altered transcriptional activity. In the structured homeodomain, activity scores closely aligned to a predicted structure and demonstrated position-specific constraints on amino acid substitution. In contrast, the intrinsically disordered transcriptional effector domain displayed a qualitatively different pattern of substitution effects, following compositional constraints without specific residue position requirements in the peptide chain. These compositional constraints were consistent with the acidic exposure model of transcriptional activation. We evaluated the performance of the DMS assay as a clinical variant classification tool using gold-standard classified human variants from ClinVar, identifying pathogenic variants with high specificity and moderate sensitivity. That this performance could be achieved using a synthetic reporter assay in a foreign cell type, even for a highly cell type-specific TF like CRX, suggests that this approach shows promise for DMS of other TFs that function in cell types that are not easily accessible. Together, the results of the CRX DMS identify molecular features of the CRX effector domain and demonstrate utility for integration into the clinical variant classification pipeline. Full Article
arch Evidence for compensatory evolution within pleiotropic regulatory elements [RESEARCH] By genome.cshlp.org Published On :: 2024-10-29T06:46:07-07:00 Pleiotropy, measured as expression breadth across tissues, is one of the best predictors for protein sequence and expression conservation. In this study, we investigated its effect on the evolution of cis-regulatory elements (CREs). To this end, we carefully reanalyzed the Epigenomics Roadmap data for nine fetal tissues, assigning a measure of pleiotropic degree to nearly half a million CREs. To assess the functional conservation of CREs, we generated ATAC-seq and RNA-seq data from humans and macaques. We found that more pleiotropic CREs exhibit greater conservation in accessibility, and the mRNA expression levels of the associated genes are more conserved. This trend of higher conservation for higher degrees of pleiotropy persists when analyzing the transcription factor binding repertoire. In contrast, simple DNA sequence conservation of orthologous sites between species tends to be even lower for pleiotropic CREs than for species-specific CREs. Combining various lines of evidence, we propose that the lack of sequence conservation in functionally conserved pleiotropic CREs is owing to within-element compensatory evolution. In summary, our findings suggest that pleiotropy is also a good predictor for the functional conservation of CREs, even though this is not reflected in the sequence conservation of pleiotropic CREs. Full Article
arch Chromatin interaction maps identify oncogenic targets of enhancer duplications in cancer [RESEARCH] By genome.cshlp.org Published On :: 2024-10-29T06:46:07-07:00 As a major type of structural variants, tandem duplication plays a critical role in tumorigenesis by increasing oncogene dosage. Recent work has revealed that noncoding enhancers are also affected by duplications leading to the activation of oncogenes that are inside or outside of the duplicated regions. However, the prevalence of enhancer duplication and the identity of their target genes remains largely unknown in the cancer genome. Here, by analyzing whole-genome sequencing data in a non-gene-centric manner, we identify 881 duplication hotspots in 13 major cancer types, most of which do not contain protein-coding genes. We show that the hotspots are enriched with distal enhancer elements and are highly lineage-specific. We develop a HiChIP-based methodology that navigates enhancer–promoter contact maps to prioritize the target genes for the duplication hotspots harboring enhancer elements. The methodology identifies many novel enhancer duplication events activating oncogenes such as ESR1, FOXA1, GATA3, GATA6, TP63, and VEGFA, as well as potentially novel oncogenes such as GRHL2, IRF2BP2, and CREB3L1. In particular, we identify a duplication hotspot on Chromosome 10p15 harboring a cluster of enhancers, which skips over two genes, through a long-range chromatin interaction, to activate an oncogenic isoform of the NET1 gene to promote migration of gastric cancer cells. Focusing on tandem duplications, our study substantially extends the catalog of noncoding driver alterations in multiple cancer types, revealing attractive targets for functional characterization and therapeutic intervention. Full Article
arch Targeted and complete genomic sequencing of the major histocompatibility complex in haplotypic form of individual heterozygous samples [RESEARCH] By genome.cshlp.org Published On :: 2024-10-29T06:46:07-07:00 The human major histocompatibility complex (MHC) is a ~4 Mb genomic segment on Chromosome 6 that plays a pivotal role in the immune response. Despite its importance in various traits and diseases, its complex nature makes it challenging to accurately characterize on a routine basis. We present a novel approach allowing targeted sequencing and de novo haplotypic assembly of the MHC region in heterozygous samples, using long-read sequencing technologies. Our approach is validated using two reference samples, two family trios, and an African-American sample. We achieved excellent coverage (96.6%–99.9% with at least 30x depth) and high accuracy (99.89%–99.99%) for the different haplotypes. This methodology offers a reliable and cost-effective method for sequencing and fully characterizing the MHC without the need for whole-genome sequencing, facilitating broader studies on this important genomic segment and having significant implications in immunology, genetics, and medicine. Full Article
arch AGAP duplicons associate with structural diversity at Chromosome 10q11.22 [RESEARCH] By genome.cshlp.org Published On :: 2024-10-29T06:46:07-07:00 The 10q11.22 chromosomal region is a duplication-rich interval of the human genome and one of the last to be fully assembled. It carries copy number–variable genes associated with intellectual disability, bipolar disorder, and obesity. In this study, we characterized the structural diversity at this locus by analyzing 64 haploid assemblies produced by the Human Pangenome Reference Consortium. We identified 11 alternative haplotypes that differ in the copy number and/or orientation of large genomic segments, ranging from hundreds of kilobase pairs (kbp) to over one megabase pair (Mbp). We uncovered a 2.4 Mbp size difference between the shortest and longest haplotypes. Breakpoint analysis revealed that genomic instability results from nonallelic homologous recombination between segmental duplication (SD) pairs with varying similarity (94.4%–99.6%). Nonetheless, these pairs generally recombine at positions where their identity is higher (>99.6%). Recurrent inversions occur with different breakpoints within the same inverted SD pair. Inversion polymorphisms shuffle the entire SD arrangement, creating new predispositions to copy-number variations. The SD architecture is associated with a catarrhine-specific subgroup of the AGAP gene family, which likely triggered the accumulation of SDs at this locus over the past 25 million years of human evolution. Our results reveal extensive structural diversity and genomic instability at the 10q11.22 locus, and expand the general understanding of the mutational mechanisms behind SD-mediated rearrangements. Full Article
arch The Priority Updates from the Research Literature (PURLs) Methodology By www.jabfm.org Published On :: 2024-10-25T09:26:14-07:00 Full Article
arch An Introductory Guide to Survey Research By jdh.adha.org Published On :: 2024-10-15T09:18:41-07:00 In the dental hygiene discipline, evidence-based practice serves as a cornerstone for delivering high quality patient care and moving professional standards forward. As practitioners delve deeper into research to inform clinical decision making, the integration of robust survey methodologies becomes imperative. However, the complexities of survey design, implementation, and analysis pose notable challenges, particularly in ensuring the reliability and validity of research outcomes. This short report provides brief practical guidance about the basics of survey research methodologies for dental hygiene professionals. Full Article
arch NEAT1 promotes genome stability via m6A methylation-dependent regulation of CHD4 [Research Papers] By genesdev.cshlp.org Published On :: 2024-10-16T07:18:56-07:00 Long noncoding (lnc)RNAs emerge as regulators of genome stability. The nuclear-enriched abundant transcript 1 (NEAT1) is overexpressed in many tumors and is responsive to genotoxic stress. However, the mechanism that links NEAT1 to DNA damage response (DDR) is unclear. Here, we investigate the expression, modification, localization, and structure of NEAT1 in response to DNA double-strand breaks (DSBs). DNA damage increases the levels and N6-methyladenosine (m6A) marks on NEAT1, which promotes alterations in NEAT1 structure, accumulation of hypermethylated NEAT1 at promoter-associated DSBs, and DSB signaling. The depletion of NEAT1 impairs DSB focus formation and elevates DNA damage. The genome-protective role of NEAT1 is mediated by the RNA methyltransferase 3 (METTL3) and involves the release of the chromodomain helicase DNA binding protein 4 (CHD4) from NEAT1 to fine-tune histone acetylation at DSBs. Our data suggest a direct role for NEAT1 in DDR. Full Article
arch YY1 knockout in pro-B cells impairs lineage commitment, enabling unusual hematopoietic lineage plasticity [Research Papers] By genesdev.cshlp.org Published On :: 2024-10-16T07:18:56-07:00 During B-cell development, cells progress through multiple developmental stages, with the pro-B-cell stage defining commitment to the B-cell lineage. YY1 is a ubiquitous transcription factor that is capable of both activation and repression functions. We found here that knockout of YY1 at the pro-B-cell stage eliminates B lineage commitment. YY1 knockout pro-B cells can generate T lineage cells in vitro using the OP9-DL4 feeder system and in vivo after injection into sublethally irradiated Rag1–/– mice. These T lineage-like cells lose their B lineage transcript profile and gain a T-cell lineage profile. Single-cell RNA-seq experiments showed that as YY1 knockout pro-B cells transition into T lineage cells in vitro, various cell clusters adopt transcript profiles representing a multiplicity of hematopoietic lineages, indicating unusual lineage plasticity. In addition, YY1 KO pro-B cells in vivo can give rise to other hematopoietic lineages in vivo. Evaluation of RNA-seq, scRNA-seq, ChIP-seq, and scATAC-seq data indicates that YY1 controls numerous chromatin-modifying proteins leading to increased accessibility of alternative lineage genes in YY1 knockout pro-B cells. Given the ubiquitous nature of YY1 and its dual activation and repression functions, YY1 may regulate commitment in multiple cell lineages. Full Article
arch A germline PAF1 paralog complex ensures cell type-specific gene expression [Research Papers] By genesdev.cshlp.org Published On :: 2024-10-16T07:18:56-07:00 Animal germline development and fertility rely on paralogs of general transcription factors that recruit RNA polymerase II to ensure cell type-specific gene expression. It remains unclear whether gene expression processes downstream from such paralog-based transcription is distinct from that of canonical RNA polymerase II genes. In Drosophila, the testis-specific TBP-associated factors (tTAFs) activate over a thousand spermatocyte-specific gene promoters to enable meiosis and germ cell differentiation. Here, we show that efficient termination of tTAF-activated transcription relies on testis-specific paralogs of canonical polymerase-associated factor 1 complex (PAF1C) proteins, which form a testis-specific PAF1C (tPAF). Consequently, tPAF mutants show aberrant expression of hundreds of downstream genes due to read-in transcription. Furthermore, tPAF facilitates expression of Y-linked male fertility factor genes and thus serves to maintain spermatocyte-specific gene expression. Consistently, tPAF is required for the segregation of meiotic chromosomes and male fertility. Supported by comparative in vivo protein interaction assays, we provide a mechanistic model for the functional divergence of tPAF and the PAF1C and identify transcription termination as a developmentally regulated process required for germline-specific gene expression. Full Article
arch Dysregulating mTORC1-4E-BP2 signaling in GABAergic interneurons impairs hippocampus-dependent learning and memory [RESEARCH PAPERS] By learnmem.cshlp.org Published On :: 2024-10-28T08:52:55-07:00 Memory formation is contingent on molecular and structural changes in neurons in response to learning stimuli—a process known as neuronal plasticity. The initiation step of mRNA translation is a gatekeeper of long-term memory by controlling the production of plasticity-related proteins in the brain. The mechanistic target of rapamycin complex 1 (mTORC1) controls mRNA translation, mainly through phosphorylation of the eukaryotic initiation factor 4E (eIF4E)-binding proteins (4E-BPs) and ribosomal protein S6 kinases (S6Ks). mTORC1 signaling decreases throughout brain development, starting from the early postnatal period. Here, we discovered that in mice, the age-dependent decrease in mTORC1 signaling occurs selectively in excitatory but not inhibitory neurons. Using a gene conditional knockout (cKO) strategy, we demonstrate that either up- or downregulating the mTORC1-4E-BP2 axis in GAD65 inhibitory interneurons, but not excitatory neurons, results in long-term object recognition and object location memory deficits. Our data indicate that the mTORC1 pathway in inhibitory but not excitatory neurons plays a key role in memory formation. Full Article
arch The influence of categorical stimuli on relational memory binding [RESEARCH PAPERS] By learnmem.cshlp.org Published On :: 2024-10-31T09:40:31-07:00 Binding of arbitrary information into distinct memory representations that can be used to guide behavior is a hallmark of relational memory. What is and is not bound into a memory representation and how those things influence the organization of that representation remain topics of interest. While some information is intentionally and effortfully bound—often the information that is consistent with task goals or expectations about what information may be required later—other information appears to be bound automatically. The present set of experiments sought to investigate whether spatial memory would be systematically influenced by the presence and absence of distinct categories of stimuli on a spatial reconstruction task. In this task, participants must learn multiple item-location bindings and place each item back in its studied location after a short delay. Across three experiments, participants made significantly more within-category errors (i.e., misassigning one item to the location of a different item from the same category) than between-category errors (i.e., misassigning one item to the location of an item from a different category) when categories were perceptually or semantically distinct. These data reveal that category information contributed to the organization of the memory representation and influenced spatial reconstruction performance. Together, these results suggest that categorical information can influence memory organization, and not always to the benefit of overall task performance. Full Article
arch Characteristics of exacerbators in the US Bronchiectasis and NTM Research Registry: a cross-sectional study By beta.openres.ersjournals.com Published On :: 2024-11-11T01:50:25-08:00 Background Exacerbations of noncystic fibrosis bronchiectasis (bronchiectasis) are associated with reduced health-related quality of life and increased mortality, likelihood of hospitalisation and lung function decline. This study investigated patient clinical characteristics associated with exacerbation frequency. Methods A cross-sectional cohort study of patients ≥18 years with bronchiectasis enrolled in the US Bronchiectasis and Nontuberculous Mycobacteria (NTM) Research Registry (BRR) September 2008–March 2020. Patients were stratified by exacerbation frequency in their 2 years before enrolment. Patient demographics, respiratory symptoms, healthcare resource utilisation, microbiology, modified bronchiectasis severity index (mBSI) and select comorbidities were collected at enrolment. Patient characteristics associated with exacerbation frequency were assessed using a negative binomial model. Results The study included 2950 patients (mean age 65.6 years; 79.1% female). Frequency of moderate to severe airway obstruction (forced expiratory volume in 1 s (FEV1) % predicted <50%; most recent measure) was 15.9%, 17.8%, and 24.6% in patients with 1, 2, and ≥3 exacerbations versus 8.9% in patients with 0 exacerbations; severe disease (mBSI) was 27.8%, 24.2% and 51.1% versus 13.2%; respiratory hospitalisation was 24.5%, 33.0% and 36.5% versus 4.1%; and Pseudomonas aeruginosa infection was 18.8%, 23.4% and 35.2% versus 11.9%. In multivariable model analysis, respiratory hospitalisation, cough, haemoptysis, P. aeruginosa, younger age, lower FEV1% predicted, asthma, and gastro-oesophageal reflux disease were associated with more exacerbations. Conclusions These findings demonstrate a high disease burden, including increased respiratory symptoms, healthcare resource utilisation, and P. aeruginosa infection in patients with bronchiectasis and multiple exacerbations. Full Article
arch Documenting the Provision of Emergency Contraceptive Pills Through Youth-Serving Delivery Channels: Exploratory Mixed Methods Research on Malawi’s Emergency Contraception Strategy By ghspjournal.org Published On :: 2024-10-29T12:28:39-07:00 ABSTRACTIntroduction:Emergency contraceptive pills (ECPs) are effective and can be used safely at any age repeatedly within the same cycle. They are often favored by youth yet are underutilized. Private facilities can increase ECP access but present barriers including cost. Identifying effective public-sector ECP distribution models can help ensure equitable access. The Malawi Ministry of Health developed a strategy to improve ECP access in 2020. We documented ECP provision through select public, youth-serving channels recommended by the strategy: general and youth-specific outreach, paid and unpaid community health workers (CHWs), and youth clubs.Methods:We conducted this mixed methods study from November 2022–March 2023 in 2 rural districts (Mchinji and Phalombe) implementing the strategy. We conducted qualitative interviews with 10 national stakeholders, 46 providers, and 24 clients aged 15–24 years about ECP service delivery. Additionally, 25 providers collected quantitative tally data about clients seeking ECPs. We analyzed qualitative data using grounded theory and quantitative data descriptively.Results:Stakeholders and providers reported ECP uptake increased in geographies where the strategy was implemented, especially among youth. Providers documented 3,988 client visits for ECPs over 3 months. Of these visits, 26% were from male clients, 36% were from clients aged younger than 20 years, and 64% received ECPs for the first time. Across channels, youth club leaders and unpaid CHWs reported the most client visits per provider and served the youngest clients. However, no ECPs were dispensed during 29% of visits due to stock-outs. While many providers were supportive of youth accessing ECPs, most held unfavorable attitudes toward repeat use.Conclusion:ECP access should be expanded through provision in the studied channels, especially youth clubs and CHWs. However, to meet demand, the supply chain must be strengthened. We recommend addressing providers’ attitudes about repeat use to ensure informed method choice. Full Article
arch The National Center for Complementary and Integrative Health: Priorities for Cannabis and Cannabinoid Research [Special Section: Cannabinoid Signaling in Human Health and Disease-Commentary] By jpet.aspetjournals.org Published On :: 2024-10-18T07:04:15-07:00 The National Center for Complementary and Integrative Health (NCCIH), which is part of the US National Institutes of Health (NIH), has a broad interest in studying the biologic activities of natural products, especially those for which compelling evidence from preclinical research suggests biologic activities that may be beneficial to health or have a potential role in disease treatment, as well as products used extensively by the American public. As of 2023, use of cannabis for medical purposes is legal in 38 states and Washington, D.C. Such use continues to climb generally without sufficient knowledge regarding risks and benefits. In keeping with NCCIH’s natural product research priorities and recognizing this gap in knowledge, NCCIH formally launched a research program in 2019 to expand research on the possible benefits for pain management of certain substances found in cannabis: minor cannabinoids and terpenes. This Viewpoint provides additional details and the rationale for this research priority at NCCIH. In addition, NCCIH’s efforts and initiatives to facilitate and coordinate an NIH research agenda focused on cannabis and cannabinoid research are described. SIGNIFICANCE STATEMENT Use of cannabis for purported medical purposes continues to increase despite insufficient knowledge regarding risks and benefits. Research is needed to help health professionals and patients make knowledgeable decisions about using cannabis and cannabinoids for medical purposes. The National Center for Complementary and Integrative Health, along with other NIH Institutes, Centers, and Offices, is expanding study on the safety, efficacy, and harms of cannabis—a complex mixture of phytochemicals that needs to be studied alone and in combination. Full Article
arch Cannabis and Cannabinoid Signaling: Research Gaps and Opportunities [Special Section: Cannabinoid Signaling in Human Health and Disease-Commentary] By jpet.aspetjournals.org Published On :: 2024-10-18T07:04:15-07:00 Cannabis and its products have been used for centuries for both medicinal and recreational purposes. The recent widespread legalization of cannabis has vastly expanded its use in the United States across all demographics except for adolescents. Meanwhile, decades of research have advanced our knowledge of cannabis pharmacology and particularly of the endocannabinoid system with which the components of cannabis interact. This research has revealed multiple targets and approaches for manipulating the system for therapeutic use and to ameliorate cannabis toxicity or cannabis use disorder. Research has also led to new questions that underscore the potential risks of its widespread use, particularly the enduring consequences of exposure during critical windows of brain development or for consumption of large daily doses of cannabis with high content 9-tetrahydrocannabinol. This article highlights current neuroscience research on cannabis that has shed light on therapeutic opportunities and potential adverse consequences of misuse and points to gaps in knowledge that can guide future research. SIGNIFICANCE STATEMENT Cannabis use has escalated with its increased availability. Here, the authors highlight the challenges of cannabis research and the gaps in our knowledge of cannabis pharmacology and of the endocannabinoid system that it targets. Future research that addresses these gaps is needed so that the endocannabinoid system can be leveraged for safe and effective use. Full Article
arch Preoperative Assessment of Meningioma Consistency Using a Combination of MR Elastography and DTI [RESEARCH] By www.ajnr.org Published On :: 2024-11-07T15:14:12-08:00 BACKGROUND AND PURPOSE: Preoperative assessment of meningioma consistency is beneficial for optimizing surgical strategy and prognosis of patients. We aim to develop a noninvasive prediction model for meningioma consistency utilizing MR elastography and DTI. MATERIALS AND METHODS: Ninety-four patients (52 ± 22 years old, 69 women, 25 men) diagnosed with meningioma were recruited in the study. Each patient underwent preoperative T1WI, T2WI, DTI, and MR elastography. Combined MR elastography–DTI model was developed based on multiple logistic regression. Intraoperative tumor descriptions served as clinical criteria for evaluating meningioma consistency. The diagnostic efficacy in determining meningioma consistency was evaluated by using a receiver operating characteristic curve. Further validation was conducted in 27 stereotactic biopsies by using indentation tests and underlying mechanism was investigated by histologic analysis. RESULTS: Among all the imaging modalities, MR elastography demonstrated the highest efficacy with the shear modulus magnitude (|G*|) achieving an area under the curve (AUC) of 0.81 (95% CI: 0.699–0.929). When combined with DTI, the diagnostic accuracy further increased (AUC: 0.88, 95% CI: 0.784–0.971), surpassing any technique alone. Indentation measurement based on stereotactic biopsies further demonstrated that the MR elastography–DTI model was suitable for predicting intratumor consistency. Histologic analysis suggested that meningioma consistency may be correlated with tumor cell density and fibrous content. CONCLUSIONS: The MR elastography–DTI combined model is effective in noninvasive prediction of meningioma consistency. Full Article
arch Neuroimaging Correlates with Clinical Severity in Wilson Disease: A Multiparametric Quantitative Brain MRI [RESEARCH] By www.ajnr.org Published On :: 2024-11-07T15:14:12-08:00 BACKGROUND AND PURPOSE: Previous studies have reported metal accumulation and microstructure changes in deep gray nuclei (DGN) in Wilson disease (WD). However, there are limited studies that investigate whether there is metal accumulation and microstructure changes in DGN of patients with WD with normal-appearing routine MRI. This study aimed to evaluate multiparametric changes in DGN of WD and whether the findings correlate with clinical severity in patients with WD. MATERIALS AND METHODS: The study enrolled 28 patients with WD (19 with neurologic symptoms) and 25 controls. Fractional anisotropy (FA), mean diffusivity (MD), and magnetic susceptibility in globus pallidus, pontine tegmentum, dentate nucleus, red nucleus, head of caudate nucleus, putamen, substantia nigra, and thalamus were extracted. Correlations between imaging data and the Unified Wilson’s Disease Rating Scale (UWDRS) neurologic subitems were explored. RESULTS: FA, MD, and susceptibility values were higher in multiple DGN of patients with WD than controls (P < .05). Patients with WD without abnormal signals in DGN on routine MRI also had higher FA, MD, and susceptibility values than controls (P < .017). We found that UWDRS neurologic subscores correlated with FA and susceptibility values of DGN (P < .05). In addition, we also found that FA and susceptibility values in specific structures correlated with specific neurologic symptoms of WD (ie, tremor, parkinsonism, dysarthria, dystonia, and ataxia) (P < .05). CONCLUSIONS: Patients with WD have increased FA, MD, and susceptibility values even before the lesion is morphologically apparent on routine MRI. The increased FA and susceptibility values correlate with clinical severity of WD. Full Article
arch Automated Volumetric Software in Dementia: Help or Hindrance to the Neuroradiologist? [RESEARCH] By www.ajnr.org Published On :: 2024-11-07T15:14:12-08:00 BACKGROUND AND PURPOSE: Brain atrophy occurs in the late stage of dementia, yet structural MRI is widely used in the work-up. Atrophy patterns can suggest a diagnosis of Alzheimer disease (AD) or frontotemporal dementia (FTD) but are difficult to assess visually. We hypothesized that the availability of a quantitative volumetric brain MRI report would increase neuroradiologists’ accuracy in diagnosing AD, FTD, or healthy controls compared with visual assessment. MATERIALS AND METHODS: Twenty-two patients with AD, 17 with FTD, and 21 cognitively healthy patients were identified from the electronic health systems record and a behavioral neurology clinic. Four neuroradiologists evaluated T1-weighted anatomic MRI studies with and without a volumetric report. Outcome measures were the proportion of correct diagnoses of neurodegenerative disease versus normal aging ("rough accuracy") and AD versus FTD ("exact accuracy"). Generalized linear mixed models were fit to assess whether the use of a volumetric report was associated with higher accuracy, accounting for random effects of within-rater and within-subject variability. Post hoc within-group analysis was performed with multiple comparisons correction. Residualized volumes were tested for an association with the diagnosis using ANOVA. RESULTS: There was no statistically significant effect of the report on overall correct diagnoses. The proportion of "exact" correct diagnoses was higher with the report versus without the report for AD (0.52 versus 0.38) and FTD (0.49 versus 0.32) and lower for cognitively healthy (0.75 versus 0.89). The proportion of "rough" correct diagnoses of neurodegenerative disease was higher with the report than without the report within the AD group (0.59 versus 0.41), and it was similar within the FTD group (0.66 versus 0.63). Post hoc within-group analysis suggested that the report increased the accuracy in AD (OR = 2.77) and decreased the accuracy in cognitively healthy (OR = 0.25). Residualized hippocampal volumes were smaller in AD (mean difference –1.8; multiple comparisons correction, –2.8 to –0.8; P < .001) and FTD (mean difference –1.2; multiple comparisons correction, –2.2 to –0.1; P = .02) compared with cognitively healthy. CONCLUSIONS: The availability of a brain volumetric report did not improve neuroradiologists’ accuracy over visual assessment in diagnosing AD or FTD in this limited sample. Post hoc analysis suggested that the report may have biased readers incorrectly toward a diagnosis of neurodegeneration in cognitively healthy adults. Full Article