Publications by authors named "O W Howell"

Among the intrathecal inflammatory niches where compartmentalized inflammation persists and plays a pivotal role in progressive multiple sclerosis (MS), choroid plexus (CP) has recently received renewed attention. To better characterize the neuropathological/molecular correlates of CP in progressive MS and its potential link with other brain inflammatory compartments, such as perivascular spaces and leptomeninges, the levels, composition and phenotype of CP immune infiltration in lateral ventricles of the hippocampus were examined in 40 post-mortem pathologically confirmed MS and 10 healthy donors, using immunochemistry/immunofluorescence and in-situ sequencing. Significant inflammation was detected in the CP of 21 out of the 40 MS cases (52%).

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Clustered regularly-interspaced short palindromic repeats (CRISPRs) and CRISPR-associated (Cas) proteins protect bacteria and archaea from their viruses, and anti-CRISPRs (Acrs) are small virus-encoded proteins that inhibit CRISPR-Cas immunity. Over 80 families of Acrs have been described to date; however, only three of these subvert Type III CRISPR-Cas immunity. Type III systems employ a complex network of Cas and accessory nucleases to degrade viral nucleic acids.

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Introduction: This study compared the clinical effectiveness of switching from tumor necrosis factor inhibitor (TNFi) to upadacitinib (TNFi-UPA), another TNFi (TNFi-TNFi), or an advanced therapy with another mechanism of action (TNFi-other MOA) in patients with rheumatoid arthritis (RA).

Methods: Data were drawn from the Adelphi RA Disease Specific Programme™, a cross-sectional survey administered to rheumatologists and their consulting patients in Germany, France, Italy, Spain, the UK, Japan, Canada, and the USA from May 2021 to January 2022. Patients who switched treatment from an initial TNFi were stratified by subsequent therapy of interest: TNFi-UPA, TNFi-TNFi, or TNFi-other MOA.

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Background: Multiple sclerosis (MS) is a clinically heterogeneous disease underpinned by inflammatory, demyelinating and neurodegenerative processes, the extent of which varies between individuals and over the course of the disease. Recognising the clinicopathological features that most strongly associate with disease outcomes will inform future efforts at patient phenotyping.

Aims: We used a digital pathology workflow, involving high-resolution image acquisition of immunostained slides and opensource software for quantification, to investigate the relationship between clinical and neuropathological features in an autopsy cohort of progressive MS.

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Clinical, pathological, and imaging evidence in multiple sclerosis (MS) suggests that a smoldering inflammatory activity is present from the earliest stages of the disease and underlies the progression of disability, which proceeds relentlessly and independently of clinical and radiological relapses (PIRA). The complex system of pathological events driving "chronic" worsening is likely linked with the early accumulation of compartmentalized inflammation within the central nervous system as well as insufficient repair phenomena and mitochondrial failure. These mechanisms are partially lesion-independent and differ from those causing clinical relapses and the formation of new focal demyelinating lesions; they lead to neuroaxonal dysfunction and death, myelin loss, glia alterations, and finally, a neuronal network dysfunction outweighing central nervous system (CNS) compensatory mechanisms.

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