Frontiers in congenital disorders of glycosylation consortium, a cross-sectional study report at year 5 of 280 individuals in the natural history cohort.

OBJECTIVE: Our report describes clinical, genetic, and biochemical features of participants with a molecularly confirmed congenital disorder of glycosylation (CDG) enrolled in the Frontiers in Congenital Disorders of Glycosylation (FCDGC) Natural History cohort at year 5 of the study. METHODS: We enrolled individuals with a known or suspected CDG into the FCDGC Natural History Study, a multicenter prospective and retrospective natural history study of all genetic causes of CDG. We conducted a cross-sectional analysis of baseline study visit data from participants with confirmed CDG who were consented into the FCDGC Natural History Study (5U54NS115198) from October 2019 to November 2023. RESULTS: Three hundred thirty-three subjects consented to the FCDGC Natural History Study. Of these, 280 unique individuals had genetic data available that was consistent with a diagnosis of CDG. These 280 individuals were enrolled into the study between October 8, 2019 and November 29, 2023. One hundred forty-one (50.4%) were female, and 139 (49.6%) were male. Mean and median age at enrollment was 10.1 and 6.5 years, respectively, with a range of 0.22 to 71.4 years. The cohort encompassed individuals with disorders of N-linked protein glycosylation (57%), glycosylphosphatidylinositol anchor disorder (GPI anchor) (15%), disorders of Golgi homeostasis, trafficking and transport (12%), dolichol metabolism disorders (5%), disorders of multiple pathways (6%), and other (5%). The most frequent presenting symptom(s) leading to diagnosis were developmental delay/disability (77%), followed by hypotonia (56%) and feeding difficulties (42%). Mean and median time between first related symptom and diagnosis was 2.7 and 0.8 years, respectively. One hundred percent of individuals in our cohort had developmental differences/disabilities at the time of their baseline visit, followed by 97% with neurologic involvement, 91% with gastrointestinal (GI)/liver involvement, and 88% with musculoskeletal involvement. Severity of disease in individuals was scored on the Nijmegen Progression CDG Rating Scale (NPCRS) with 27% of scores categorized as mild, 44% moderate, and 29% severe. Of the individuals with N-linked protein glycosylation defects, 83% of those with data showed a type 1 pattern on carbohydrate deficient transferrin (CDT) analysis including 82/84 individuals with PMM2-CDG, 6% a type 2 pattern, 1% both type 1 and type 2 pattern and 10% a normal or nonspecific pattern. One hundred percent of individuals with Golgi homeostasis and trafficking defects with data showed a type 2 pattern on CDT analysis, while Golgi transport defect showed a type II pattern 73% of the time, a type 1 pattern for 7%, and 20% had a normal or nonspecific pattern. Most of the variants documented were classified as pathogenic or likely pathogenic using ACMG criteria. For the majority of the variants, the predicted molecular consequence was missense followed by nonsense and splice site, and the majority of the diagnoses are inherited in an autosomal recessive pattern but with disorders of all major nuclear inheritance included. DISCUSSION: The FCDGC Natural History Study serves as an important resource to build future research studies, improve clinical care, and prepare for clinical trial readiness. Herein is the first overview of CDG participants of the FCDGC Natural History Study.

A cross-sectional study of participant recruitment rates in published phase III influenza therapeutic randomized controlled trials conducted in the clinical setting.

OBJECTIVE: A recent academic-government partnership demonstrated the feasibility of utilizing Emergency Departments (ED) as a primary site for subject enrollment in clinical trials and achieved high rates of recruitment in two U.S. EDs. Given the ongoing need to test new therapeutics for influenza and other emerging infections, we sought to describe the historical rates of participant recruitment into influenza Phase III therapeutic RCTs in various clinical venues, including EDs. STUDY DESIGN: A cross-sectional study was performed of influenza therapeutic Phase III RCTs published in PubMed, Embase, Scopus, and Clinicaltrials.gov from January 2000 to June 2019. MAIN OUTCOME: To estimate the weighted-average number of influenza-positive participants enrolled per site per season in influenza therapeutic RCT conducted in clinical settings, and to describe basic trial site characteristics. RESULTS: 47 (0.7%) of 7008 articles were included for review of which 43 of 47 (91%) included information regarding enrollment sites; of these, 2 (5%) recruited exclusively from EDs with the remainder recruiting from mixed clinical settings (inpatient, outpatient, and ED). The median enrollment per study was 326 (IQR: 110, 502.5) with a median of 11 sites per study (IQR: 2, 59.5). Included studies reported a median of 201 (IQR: 74, 344.5) confirmed influenza-positive participants per study. The pooled number of participants enrolled per site per season was 11 (95% CI: 10, 12). The pooled enrollment numbers per clinical site after excluding the two 'ED only recruitment' studies were less [10.7 (95% CI: 9.9, 11.6)] than the pooled enrollment numbers per clinical site for the two 'ED only recruitment' studies [89.5 (95% CI 89.2-89.27)]. CONCLUSION AND RELEVANCE: Published RCTs evaluating influenza therapeutics in clinical settings recruit participants from multiple sites but enroll relatively few participants, per site, per season. The few ED-based studies reported recruited more subjects per site per season. Untapped opportunities likely exist for EDs to participate and/or lead therapeutic RCTs for influenza or other emerging respiratory pathogens.

Physical Exercise Improves Cognitive Outcomes in 2 Models of Transient Cerebral Ischemia.

BACKGROUND AND PURPOSE: Preclinical studies suggest that exercise can enhance cognition after cerebral ischemia but often use long training regiments and test cognition during or acutely after training. The cognitive changes may result from enhanced physical fitness and may only provide acute benefit. We sought to determine whether a short period of exercise after cerebral ischemia could improve cognitive outcomes when measured days after completion of exercise training in 2 cerebral ischemia models. METHODS: Focal or global cerebral ischemia was induced in Sprague-Dawley rats. Rats recovered (3-4 days) then were subject to no exercise (0 m/min), mild (6 m/min), moderate (10 m/min), or heavy (15-18 m/min) treadmill exercise (5-6 days). Cognition was tested 8 to 10 days after the last exercise session with hippocampal-dependent contextual fear conditioning. RESULTS: A short training period of moderate exercise enhanced cognitive function for a week after exercise completion in both models of cerebral ischemia. CONCLUSIONS: Utilization of this exercise paradigm can further the elucidation of exercise-mediated factors involved in cognitive recovery independent of changes in physical fitness.

Sex-Dependent Differences in Physical Exercise-Mediated Cognitive Recovery Following Middle Cerebral Artery Occlusion in Aged Rats.

Stroke remains a leading cause of death and disability in the United States. No current treatments exist to promote cognitive recovery in survivors of stroke. A previous study from our laboratory determined that an acute bout of forced treadmill exercise was able to promote cognitive recovery in 3 month old male rats after middle cerebral artery occlusion (MCAo). In this study, we tested the hypothesis that 6 days of intense acute bout of forced treadmill exercise (physical exercise - PE) promotes cognitive recovery in 11-14 month old male rats. We determined that PE was able to ameliorate cognitive deficits as determined by contextual fear conditioning. Additionally, we also tested the hypothesis that PE promotes cognitive recovery in 11-13 month old reproductive senescent female rats. In contrast to males, the same intensity of exercise that decrease cognitive deficits in males was not able to promote cognitive recovery in female rats. Additionally, we determined that exercise did not lessen infarct volume in both male and female rats. There are many factors that contribute to higher stroke mortality and morbidities in women and thus, future studies will investigate the effects of PE in aged female rats to identify sex differences.

Cognitive Deficits after Cerebral Ischemia and Underlying Dysfunctional Plasticity: Potential Targets for Recovery of Cognition.

Cerebral ischemia affects millions of people worldwide and survivors suffer from long-term functional and cognitive deficits. While stroke and cardiac arrest are typically considered when discussing ischemic brain injuries, there is much evidence that smaller ischemic insults underlie neurodegenerative diseases, including Alzheimer's disease. The "regenerative" capacity of the brain relies on several aspects of plasticity that are crucial for normal functioning; less affected brain areas may take over function previously performed by irreversibly damaged tissue. To harness the endogenous plasticity mechanisms of the brain to provide recovery of cognitive function, we must first understand how these mechanisms are altered after damage, such as cerebral ischemia. In this review, we discuss the long-term cognitive changes that result after cerebral ischemia and how ischemia alters several plasticity processes. We conclude with a discussion of how current and prospective therapies may restore brain plasticity and allow for recovery of cognitive function, which may be applicable to several disorders that have a disruption of cognitive processing, including traumatic brain injury and Alzheimer's disease.

Protein kinase C epsilon delays latency until anoxic depolarization through arc expression and GluR2 internalization.

Global cerebral ischemia is a debilitating injury that damages the CA1 region of the hippocampus, an area important for learning and memory. Protein kinase C epsilon (PKCɛ) activation is a critical component of many neuroprotective treatments. The ability of PKCɛ activation to regulate AMPA receptors (AMPARs) remains unexplored despite the role of AMPARs in excitotoxicity after brain ischemia. We determined that PKCɛ activation increased expression of a protein linked to learning and memory, activity-regulated cytoskeleton-associated protein (arc). Also, arc is necessary for neuroprotection and confers protection through decreasing AMPAR currents via GluR2 internalization. In vivo, activation of PKCɛ increased arc expression through a BDNF/TrkB pathway, and decreased GluR2 mRNA levels. In hippocampal cultured slices, PKCɛ activation decreased AMPAR current amplitudes in an arc- and GluR2-dependent manner. Additionally, PKCɛ activation triggered an arc- and GluR2 internalization-dependent delay in latency until anoxic depolarization. Inhibiting arc also blocked PKCɛ-mediated neuroprotection against lethal oxygen and glucose deprivation. These data characterize a novel PKCɛ-dependent mechanism that for the first time defines a role for arc and AMPAR internalization in conferring neuroprotection.