23834 research outputs found
Sort by
The night\u27s watch: Exploring how sleep protects against neurodegeneration
No full textSleep loss is often regarded as an early manifestation of neurodegenerative diseases given its common occurrence and link to cognitive dysfunction. However, the precise mechanisms by which sleep disturbances contribute to neurodegeneration are not fully understood, nor is it clear why some individuals are more susceptible to these effects than others. This review addresses critical unanswered questions in the field, including whether sleep disturbances precede or result from neurodegenerative diseases, the functional significance of sleep changes during the preclinical disease phase, and the potential role of sleep homeostasis as an adaptive mechanism enhancing resilience against cognitive decline and neurodegeneration
Belumosudil reduces oral chronic graft-versus-host disease tissue inflammation and fibrosis: A ROCKstar companion study
No full textBelumosudil (KD025), an oral, selective, Rho-associated, coiled-coil-containing protein kinase 2 (ROCK2) inhibitor, is approved for third-line treatment of chronic graft-versus-host disease (cGVHD). Previous studies demonstrated that ROCK2 inhibition reduces blood interleukin-17 (IL-17) activity and promotes regulatory T-cell (Treg cell) recovery. However, these studies did not evaluate immune responses within cGVHD-affected tissues. This study assessed tissue-level immune dynamics in 20 patients with oral cGVHD from the phase 2 ROCKstar trial, before and after 6 months of belumosudil treatment, focusing on key effector sites (oral mucosa [OM], minor salivary glands [MSGs], and skin) and the peripheral blood. After belumosudil treatment, reduction in collagen was observed in OM in parallel with decreased IL-17+ cell frequency in both OM (n = 14 pairs) and MSG (n = 11 pairs). IL-17 was primarily produced by non-T cells in the oral tissues. Immune cell frequencies in the OM decreased after treatment, whereas CD4 Treg cells increased in both the MSG and blood. Per overall or mouth-specific clinical response criteria, responders to belumosudil exhibited a reduction in collagen type I and IL-17 in the OM. Additionally, salivary transforming growth factor β1 (TGF-β1), a critical driver of fibrosis, decreased significantly, with a strong correlation observed between TGF-β1 and IL-17 levels. These findings illustrate the tissue-level response to belumosudil therapy and suggest that there is a reduction in tissue fibrosis and inflammation, thereby highlighting the therapeutic impact of ROCK2 inhibition in mitigating cGVHD. The ROCKstar study was registered at www.ClinicalTrials.gov as #NCT03640481
Fucosylated N-glycan landscape of triple-negative breast cancer
No full textUNLABELLED: Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer lacking targeted therapies. Although aberrant N-glycosylation is a hallmark of malignancy, the specific roles of core-fucosylated (CF) and outer arm-fucosylated (OAF) N-glycans in TNBC progression and patient survival remain underexplored. This study utilized multiplexed glycomics by matrix-assisted laser desorption/ionization imaging mass spectrometry to spatially profile 348 N-glycans in 59 TNBC tumors with clinical characteristics including survival data. Spatial analysis revealed distinct localization patterns of CF and OAF isomers within tumor microenvironments. Strikingly, OAF glycans, but not CF, were strongly associated with tumor stage, with expression increasing from stage I to III and then declining in stage IV. Furthermore, 68 N-glycans were significantly associated with survival outcomes; 36 (52%) of these were OAF-modified, including polylactosamine structures previously linked to metastasis in breast cancer. High expression of OAF polylactosamines correlated with poor prognosis and was detectable in early-stage TNBC tumors, underscoring their potential as prognostic biomarkers.
IMPLICATIONS: These findings demonstrate that OAF N-glycans are dynamic, structure-specific markers of TNBC progression and survival, and their early detection and strong prognostic value highlight potential utility in patient stratification and personalized therapy
Muscle biopsy findings in valosin-containing protein multisystem proteinopathy
No full textBACKGROUND AND OBJECTIVES: Valosin Containing Protein-associated multisystem proteinopathy (VCP-MSP) is a progressive, autosomal dominant disorder caused by pathogenic variants in the VCP gene, resulting in a heterogeneous clinical presentation. Muscle biopsy findings are characteristic but not pathognomonic. This study aimed to comprehensively analyse VCP-related myopathology and explore correlations with clinical phenotypes, genetic variants, and disease progression.
METHODS: Muscle biopsy images and data were collected retrospectively from adults (≥18 years) with pathogenic or likely pathogenic VCP variants enrolled in the VCP Multicentre International Study. Biopsy data were standardized using the Common Data Elements for Muscle Biopsy Reporting. Variations in biopsy findings were analysed by biopsy site, time from disease onset, the four most common VCP variants, and clinical phenotypes.
RESULT: A total of 112 muscle biopsies were included. Most individuals were male (66.0%). The mean age at biopsy was 53.3 years (SD 10.0), with a mean disease duration of 6.5 years (SD 4.5). The most frequent VCP variant was c.464G\u3eA (p.Arg155His) (18.8%). The top clinical phenotypes were isolated myopathy (37.5%), myopathy with Paget disease of bone (17.9%), and myopathy with motor neuron involvement (13.4%). The vastus lateralis was the most common biopsy site (34.8%), and 91% were open biopsies. Histopathologic findings included atrophic fibres (87.5%), rimmed vacuoles (72.3%), endomysial fibrosis (58.0%), and protein aggregates (51.8%), primarily p62 (60.3%) and VCP (36.2%). Degeneration niches with fibrofatty replacement and atrophic fibres were seen in 33.3% of biopsies without frequency differences by clinical phenotypes. There were no differences in biopsy findings among the 4 most common VCP gene variants, except for the absence of degeneration niches in muscle biopsies of 12 patients with c.277C\u3eT (p.Arg93Cys). MRI data from 30 patients showed fat pockets corresponding to these niches and STIR hyperintensity correlated with inflammatory infiltrates in 42.9%. Concordance between clinical phenotype, biopsy, and neurophysiology was observed in only 49.4% of cases, indicating significant heterogeneity.
DISCUSSION: VCP-MSP muscle biopsies consistently show myopathic or mixed patterns with rimmed vacuoles and p62/VCP-positive inclusions, regardless of clinical phenotype, age, or progression. Some lack vacuoles, challenging diagnosis. Discrepancies between clinical, neurophysiology, and biopsy findings should prompt consideration of VCP-MSP to improve detection and management
Transcriptome meta-analysis uncovers cell-specific regulatory relationships in embryonic, juvenile, adult, and aged mouse lens epithelium and fibers
No full textPURPOSE: The lens transcriptome has been examined using microarrays and RNA-sequencing (RNA-seq). These omics data are the basis of the bioinformatics web-resource iSyTE that has identified new genes involved in lens development and cataract. The lens predominantly contains epithelial and fiber cells, and yet, presently, iSyTE is based on whole lens data. To gain cell-specific regulatory insights, we meta-analyzed isolated epithelium and fiber transcriptomes from embryonic/postnatal, adult and aged lenses.
METHODS: Mouse lens epithelium and fiber transcriptome public datasets at embryonic (E) and postnatal (P) stages E12.5, E14.5, E16.5, E18.5, P0.5, P0, P5, P13, and age one month, three months, six months, and two years were analyzed. Microarray or RNA-seq data were analyzed by appropriate methods and compared to other resources (e.g., Cat-Map, CompBio).
RESULTS: Across all RNA-seq datasets examined, 2466 genes are differentially expressed between epithelium and fibers, of which 106 are cataract-linked. Gene ontology enrichment validates epithelial and fiber expression, corroborating the meta-analysis. Whole embryonic-body-in silico subtraction and other analyses identify several new high-priority epithelial- and/or fiber-enriched genes (e.g., Casz1, Ell2). Furthermore, new insights into cell-specific regulatory processes at distinct stages are identified (e.g., ribonucleoprotein regulation in E12.5 epithelium). Finally, this data is made accessible at iSyTE (https://research.bioinformatics.udel.edu/iSyTE/).
CONCLUSIONS: This spatiotemporal transcriptome meta-analysis comprehensively informs on epithelium- and fiber-specific regulatory processes in developing, adult and aged lenses. Notably, it includes the first description of an embryonic stage (i.e., E12.5) representing early primary fiber differentiation, thus informing on the initial transcriptome changes as lens cell-types are readily distinguishable
Single cell viral tagging of Faecalibacterium prausnitzii reveals rare bacteriophages omitted by other techniques
No full textThe associations of the gut microbiome and virome with human health and disease are increasingly numerous and clear. The mechanistic roles of bacteriophages (phages) in the microbiome, however, are especially unclear, as their cultivation is exceedingly difficult and their diversity so immense. We use viral tagging (VT), a technique wherein fluorescently stained uncultivated viruses are allowed to adsorb to host cells and then host cells are singly sorted. This method identifies interacting phage-bacteria pairs to better sample and characterize the phages in human stool samples from healthy and inflammatory bowel disease (IBD)-affected patients. First, we apply VT to uncultivated bacteria from a healthy human sample, demonstrating far-reaching ability to observe diverse bacteria and phages alike. We also use VT with a culture
Endogenous self-peptides guard immune privilege of the central nervous system
Full text linkDespite the presence of strategically positioned anatomical barriers designed to protect the central nervous system (CNS), it is not entirely isolated from the immune syste
Label free, capillary-scale blood flow mapping in vivo reveals that low-intensity focused ultrasound evokes persistent dilation in cortical microvasculature
Full text linkNon-invasive, low intensity focused ultrasound is an emerging neuromodulation technique that offers the potential for precision, personalized therapy. An increasing body of research has identified mechanosensitive ion channels that can be modulated by FUS and support acute electrical activity in neurons. However, neuromodulatory effects that persist from hours to days have also been reported. The brain\u27s ability to provide blood flow to electrically active regions involves a multitude of non-neuronal cell types and signaling pathways in the cerebral vasculature; an open question is whether persistent effects can be attributed, at least partly, to vascular mechanisms. Using an in vivo optical approach, we found that microvasculature, and not larger vessels, exhibit significant persistent dilation following sonication without the use of microbubbles. This finding reveals a heretofore unseen aspect of the effects of FUS in vivo and indicates that concurrent changes in neurovascular function may partially underly persistent neuromodulatory effects
Barcoded SARS-CoV-2 viruses define the impact of duration and route of exposure on the transmission bottleneck in a hamster model
Full text linkThe transmission bottleneck, defined as the number of viruses shed from one host to infect another, is an important determinant of the rate of virus evolution and the level of immunity required to protect against virus transmission. Despite its importance, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission bottleneck remains poorly characterized. We adapted a SARS-CoV-2 reverse genetics system to generate a pool of \u3e200 isogenic SARS-CoV-2 viruses harboring specific 6-nucleotide barcodes, infected donor hamsters with this pool, and exposed contact hamsters to paired infected donors, varying the duration and route of exposure. Following exposure, the nasal turbinates, trachea, and lungs were collected and the number of barcodes in each tissue was enumerated. We found that longer and more direct exposures increased the transmission bottleneck and that the upper airway is the primary source of transmitted virus in this model. Together, these findings highlight the utility of barcoded viruses as tools to rigorously study virus transmission
Engaging dystonia networks with subthalamic stimulation
Full text linkDeep brain stimulation is an efficacious treatment for dystonia. While the internal pallidum serves as the primary target, recently, stimulation of the subthalamic nucleus (STN) has been investigated. However, optimal targeting within this structure and its surroundings have not been studied in depth. Indeed, historical targets that have been used for surgical treatment of dystonia are directly adjacent to the STN. Further, multiple types of dystonia exist, and outcomes are variable, suggesting that not all types would profit maximally from the same target. Therefore, a thorough investigation of neural substrates underlying stimulation effects on dystonia signs and symptoms is warranted. Here, we analyze a multicenter cohort of isolated dystonia patients with subthalamic implantations