From self-induced to perceived errors – A generalized over-monitoring activity in obsessive–compulsive disorder

Well-functioning error monitoring of the inner and outer environments is essential for adaptively altering behavior, while malfunction characterizes conditions such as obsessive–compulsive disorder (OCD). The underlying brain processing is manifested as Error-Related Negativity (ERN) signal elicited following error comission, and Perceived Error Related Theta Activity (PERTA) signal elicited following detection of discrepancy in the environment. Yet, while enhanced ERN was repeatedly demonstrated in OCD patients and was found to be potentiated among their unaffected first degree relatives, no comparable observations were reported with regard to PERTA. We recorded EEG activity while OCD patients, OCD patients’ siblings (Family), and healthy controls (HC) performed computerized tasks. For the examination of ERN we used the Stroop task and for the examination of PERTA we presented correct and incorrect mathematical equations. Increased ERN (0–120 ms post response) was observed in both the OCD and Family groups, but only the OCD patients’ signal significantly differed from that of HC's. Similarly, modified PERTA activity was observed in both the OCD and Family groups in the N1 peak (65–125 ms post perceived error), but only for the OCD group this activity significantly differed from that of HC. Both ERN and PERTA's N1 are fast occurring peaks, which suggests that OCD is associate with a constantly over-activated detection system that monitors the inner and outer environment and reacts promptly following detection of a mistake. Furthermore, the modified but non-significantly different activity of the Family group suggests that the pathological condition evolves in vulnerable individuals with neuronal predisposition.     

DNA methylation of the ELOVL2, FHL2, KLF14, C1orf132/MIR29B2C,and TRIM59 genes for age prediction from blood,saliva, and buccal swab samples

Many studies have reported age-associated DNA methylation changes and age-predictive models in various tissues and body fluids. Although age-associated DNA methylation changes can be tissue-specific, a multi-tissue age predictor that is applicable to various tissues and body fluids with considerable prediction accuracy might be valuable. In this study, DNA methylation at 5 CpG sites from the ELOVL2, FHL2, KLF14, C1orf132/MIR29B2C, and TRIM59 genes were investigated in 448 samples from blood, saliva, and buccal swabs. A multiplex methylation SNaPshot assay was developed to measure DNA methylation simultaneously at the 5 CpG sites. Among the 5 CpG sites, 3 CpG sites in the ELOVL2, KLF14 and TRIM59 genes demonstrated strong correlation between DNA methylation and age in all 3 sample types. Age prediction models built separately for each sample type using the DNA methylation values at the 5 CpG sites showed high prediction accuracy with a Mean Absolute Deviation from the chronological age (MAD) of 3.478 years in blood, 3.552 years in saliva and 4.293 years in buccal swab samples. A tissue-combined model constructed with 300 training samples including 100 samples from each blood, saliva and buccal swab samples demonstrated a very strong correlation between predicted and chronological ages (r = 0.937) and a high prediction accuracy with a MAD of 3.844 years in the 148 independent test set samples of 50 blood, 50 saliva and 48 buccal swab samples. Although more validation might be needed, the tissue-combined model’s prediction accuracies in each sample type were very much similar to those obtained from each tissue-specific model. The multiplex methylation SNaPshot assay and the age prediction models in our study would be useful in forensic analysis, which frequently involves DNA from blood, saliva, and buccal swab samples.     

Missense variants in RPH3A cause defects in excitatory synaptic function and are associated with a clinically variable neurodevelopmental disorder

PurposeRPH3A encodes a protein involved in the stabilization of GluN2A subunit of N-methyl-D-aspartate (NMDA)-type glutamate receptors at the cell surface, forming a complex essential for synaptic plasticity and cognition. We investigated the effect of variants in RPH3A in patients with neurodevelopmental disorders.MethodsBy using trio-based exome sequencing, GeneMatcher, and screening of 100,000 Genomes Project data, we identified 6 heterozygous variants in RPH3A. In silico and in vitro models, including rat hippocampal neuronal cultures, have been used to characterize the effect of the variants.ResultsFour cases had a neurodevelopmental disorder with untreatable epileptic seizures [p.(Gln73His)dn; p.(Arg209Lys); p.(Thr450Ser)dn; p.(Gln508His)], and 2 cases [p.(Arg235Ser); p.(Asn618Ser)dn] showed high-functioning autism spectrum disorder. Using neuronal cultures, we demonstrated that p.(Thr450Ser) and p.(Asn618Ser) reduce the synaptic localization of GluN2A; p.(Thr450Ser) also increased the surface levels of GluN2A. Electrophysiological recordings showed increased GluN2A-dependent NMDA ionotropic glutamate receptor currents for both variants and alteration of postsynaptic calcium levels. Finally, expression of the Rph3A^Thr450Ser variant in neurons affected dendritic spine morphology.ConclusionOverall, we provide evidence that missense gain-of-function variants in RPH3A increase GluN2A-containing NMDA ionotropic glutamate receptors at extrasynaptic sites, altering synaptic function and leading to a clinically variable neurodevelopmental presentation ranging from untreatable epilepsy to autism spectrum disorder.     

Thromboprophylaxis in the oldest old with atrial fibrillation: Between Scylla and Charybdis

Within a few decades half of the patients with non-valvular atrial fibrillation (AF) will be older than 80 years. These patients are at particularly high risk of thromboembolism (Scylla) but also of the hemorrhagic complications of thromboprophylaxis (Charybdis). A frequent compromise is to use as antithrombotic agents instead of vitamin-K antagonists aspirin or other antiplatelet drugs, which are ineffective for thromboprophylaxis in the oldest old and definitely not free from a high risk of severe bleeding. All the new direct anticoagulants currently licensed (dabigatran, rivaroxaban, apixaban) are at least as effective as warfarin for thromboprophylaxis in AF, but the risk of the intracranial bleeding, the most feared complication of anticoagulant therapy, is at least halved. In the oldest patients of 80 years of age or more preliminary data, available so far only for dabigatran, indicate that the favorable outcomes of direct anticoagulants are also present in this subgroup, often left untreated for fear of intracranial bleeding. The choice between the different direct anticoagulants is driven by the presence or not of renal insufficiency, the presence and degree of multimorbidity and polypharmacy and by the likelihood or not of poor treatment adherence in patients who are often frail and with some degree of cognitive impairment.     

Aggressive resection of craniopharyngioma achieved by drilling the tuberculum sellae/planum sphenoidale using a frontal basal interhemispheric approach: A review of 55 cases

ObjectiveThe frontal basal interhemispheric approach (FBIA) is preferable for resection of craniopharyngioma (CP), achieving desirable total resection rates in early reports of lesions located in the suprasellar region to the third ventricle. For tumours that have created a larger obstruction of the tuberculum sellae and planum sphenoidale, aggressive resection in the intrasellar region and medial wall of the cavernous sinus is not feasible compared to improving tumour visualization by drilling the tuberculum sellae and planum sphenoidale. In a report of drilling the sellar tuberculum and sphenoid planum, drilling allowed the direct visualization of tumours invading the intrasellar region and medial wall of the cavernous sinus. Reconstructing the opening of the sellar-sphenoid cavity is achieved by microsuturing a piece of the pericranium/dura around the dural edge of the defective dura of the open sphenoid sinus and sellar cavity to prevent cerebrospinal fluid (CSF) leakage.Patients and methodsThe FBIA with drilling of the tuberculum sellae and planum sphenoidale was performed to remove the tumours that invaded the intrasellar region and cavernous sinus in 55 patients from January 2014 to October 2019 at our institution. The pre- and postoperative pituitary hormone levels and vision were evaluated as effective standards after surgery and compared using paired t-tests. The different rates of CSF leakage between the packing and microsuture groups were compared by χ² test, p < 0.05.ResultsIn all patients with a mean 37-month follow-up (range, 3–2 months), 43 (78.2%) patients returned to their normal life or school independently, 7 (12.7%) patients were able to perform normal activities with minor complaints or effort, and 4 (7.3%) patients could care for themselves or only required occasional assistance. One (1.8%) death occurred, attributed to CSF leak-related meningitis at 5 months after surgery. Postoperative CSF leakage occurred in eight (19.0%) of 42 patients with packed bone wax or pieces of muscle to the sphenoid sinus. Of 13 patients with a piece of the periosteum/dura microsutured around the defective dura of the sellar region and open sphenoid sinus, one (7.7%) of 13 patients experienced CSF leakage in the perioperative period. With statistical analysis, there was a potential risk for postoperative CSF leakage in the bone wax and muscle piece in the open sphenoid sinus, whereas microsuture manoeuvres were effective for avoiding the risk of postoperative CSF leakage (χ² = 8.865, p < 0.005). The microsutures closed the open sphenoid sinus such that it was water-tight. Postoperative visual acuity and the visual field were not affected by the increased intrasellar exposure or the open sphenoid sinus achieved by drilling the tuberculum sellae and planum sphenoidale.ConclusionTuberculum sellae/planum sphenoidale drilling via FBIA is feasible to enhance the direct visualization of CP resection, which expands the intrasellar region with a direct resection of recurrent tumours in the sellar cavity and adhering to the medial wall of the cavernous sinus. The potential risk of a CSF leakage seemed to be mitigated when using water-tight microsutures on a piece of the pericranium/dura around the edge of the defective dura in the sellar region and the open sphenoid sinus cavity.     

Corticosterone-mediated microglia activation affects dendritic spine plasticity and motor learning functions in minimal hepatic encephalopathy

Minimal hepatic encephalopathy (MHE) is characterized as cognitive deficits including memory and learning dysfunctions after liver injuries or hepatic diseases. Our understandings of neurological mechanisms of MHE-associated cognitive syndromes, however, are far from complete. In the current study we generated a mouse MHE model by repetitive administrations of thioacetamide (TAA), which induced hyperammonemia plus elevated proinflammatory cytokines in both the general circulation and motor cortex. MHE mice presented prominent motor learning deficits, which were associated with excess dendritic spine pruning in the motor cortex under 2-photon in vivo microscopy. The pharmaceutical blockade of glucocorticoid receptor or suppression of its biosynthesis further rescued motor learning deficits and synaptic protein loss. Moreover, MHE mice presented microglial activation, which can be alleviated after glucocorticoid pathway inhibition. In sum, our data demonstrates corticosterone-induced microglial activation, synaptic over-pruning and motor learning impairments in MHE, providing new insights for MHE pathogenesis and potential targets of clinical interventions.     

The prevalence of mild cognitive impairment and its etiological subtypes in elderly Chinese

BackgroundEpidemiologic studies on mild cognitive impairment (MCI) are limited in China.MethodsUsing a multistage cluster sampling design, a total of 10,276 community residents (6096 urban, 4180 rural) aged 65 years or older were evaluated and diagnosed with normal cognition, MCI, or dementia. MCI was further categorized by imaging into MCI caused by prodromal Alzheimer's disease (MCI-A), MCI resulting from cerebrovascular disease (MCI-CVD), MCI with vascular risk factors (MCI-VRF), and MCI caused by other diseases (MCI-O).ResultsThe prevalences of overall MCI, MCI-A, MCI-CVD, MCI-VRF, and MCI-O were 20.8% (95% confidence interval [CI] = 20.0–21.6%), 6.1% (95% CI = 5.7–6.6%), 3.8% (95% CI = 3.4–4.2%), 4.9% (95% CI = 4.5–5.4%), and 5.9% (95% CI = 5.5–6.4%) respectively. The rural population had a higher prevalence of overall MCI (23.4% vs 16.8%, P < .001).ConclusionsThe prevalence of MCI in elderly Chinese is higher in rural than in urban areas. Vascular-related MCI (MCI-CVD and MCI-VRF) was most common.