Tuberous Sclerosis Complex (TSC) is a multisystem genetic disorder characterized by hamartomatous neurological lesions that exhibit abnormal cell proliferation and differentiation. Hyperactivation of mTOR pathway by mutations in either the Tsc1 or Tsc2 gene underlies TSC pathogenesis, but involvement of specific neural cell populations in the formation of TSC-associated neurological lesions remains unclear. We deleted Tsc1 in Emx1-expressing embryonic telencephalic neural stem cells (NSCs) and found that mutant mice faithfully recapitulated TSC neuropathological lesions, such as cortical lamination defects and subependymal nodules (SENs). These alterations were caused by enhanced generation of SVZ neural progeny, followed by their premature differentiation and impaired maturation during both embryonic and postnatal development. Notably, mTORC1-dependent Akt inhibition and STAT3 activation were involved in the reduced self-renewal and earlier neuronal and astroglial differentiation of mutant NSCs. Thus, finely tuned mTOR activation in embryonic NSCs may be critical to prevent development of TSC-associated brain lesions.
The role of sirtuin 6 (SIRT6) in atherosclerotic progression of diabetic patients is unknown. We evaluated SIRT6 expression and the effect of incretin-based therapies in carotid plaques of asymptomatic diabetic and nondiabetic patients. Plaques were obtained from 52 type 2 diabetic and 30 nondiabetic patients undergoing carotid endarterectomy. Twenty-two diabetic patients were treated with drugs that work on the incretin system, GLP-1 receptor agonists, and dipeptidyl peptidase-4 inhibitors for 26 6 8 months before undergoing the endarterectomy. Compared with nondiabetic plaques, diabetic plaques had more inflammation and oxidative stress, along with a lesser SIRT6 expression and collagen content. Compared with non-GLP-1 therapy-treated plaques, GLP-1 therapy-treated plaques presented greater SIRT6 expression and collagen content, and less inflammation and oxidative stress, indicating a more stable plaque phenotype. These results were supported by in vitro observations on endothelial progenitor cells (EPCs) and endothelial cells (ECs). Indeed, both EPCs and ECs treated with high glucose (25 mmol/L) in the presence of GLP-1 (100 nmol/L liraglutide) presented a greater SIRT6 and lower nuclear factor-kB expression compared with cells treated only with high glucose. These findings establish the involvement of SIRT6 in the inflammatory pathways of diabetic atherosclerotic lesions and suggest its possible positive modulation by incretin, the effect of which is associated with morphological and compositional characteristics of a potential stable plaque phenotype.Cardiovascular disease represents the leading cause of death in patients with type 2 diabetes (1). Diabetes leads to increased vulnerability for plaque disruption, and mediates increased incidence and severity of clinical events (2). Inflammation, particularly in diabetes, plays a central role in the cascade of events that result in plaque erosion and fissuring (2). There is now increasing evidence that a number of transcription factors, including the Sir2 family of enzymes, namely sirtuins (SIRTs), regulate multiple genes whose products are putatively involved in the regulation of inflammation and endothelial cell (EC) function (3). The Sir2 family consists of seven enzymes (SIRT1 to SIRT7) that share a conserved core catalytic domain, but differ in their cellular localization and tissue distribution (4). Among the SIRTs, SIRT6, a chromatinassociated deacetylase, is considered to have a leading role in regulating genomic stability, cellular metabolism, stress response, and aging (5-8). A recent study (9) in mice suggested a role for SIRT6 in inflammation. Moreover, the knockdown of SIRT6 resulted in the increased expression of proinflammatory cytokines (interleukin [IL]-1b, IL-6, and IL-8), extracellular matrix remodeling enzymes (matrix metalloproteinase [MMP]-2, MMP-9, and plasminogen activator inhibitor 1), and intracellular adhesion molecule-1 (4). In ECs, the loss of SIRT6 was associated with an increased expression of nuclear factor-kB (NF-kB), whereas o...
Summary: Purpose:The chromosome 20 ring [r(20)] is a rare chromosomal disorder without clear phenotypical markers. We describe the electroclinical pattern in a group of patients with r(20).Methods: We observed 3 patients (a boy, patient 1; his mother, patient 2; and an unrelated man, patient 3), performing prolonged video-EEG and cytogenetic studies and fluorescent in situ hybridization (FISH) with chromosome-specific telomeric probes.
To evaluate the effect of metformin therapy on coronary endothelial function and major adverse cardiac events (MACE) in patients with prediabetes with stable angina and nonobstructive coronary stenosis (NOCS). RESEARCH DESIGN AND METHODS Metformin therapy may be needed to reduce coronary heart disease risk in patients with prediabetes. A total of 258 propensity score-matched (PSM) patients with stable angina undergoing coronary angiography were enrolled in the study. Data from 86 PSM subjects with normoglycemia (NG), 86 PSM subjects with prediabetes (pre-DM), and 86 PSM subjects with prediabetes treated with metformin (pre-DM metformin) were analyzed. During coronary angiography, NOCS was categorized by luminal stenosis <40% and fractional flow reserve >0.80. In addition, we assessed the endothelial function, measuring coronary artery diameter of left anterior descending coronary (LAD) at baseline and after the infusion of acetylcholine, by means of an intracoronary Doppler guide wire. MACE, as cardiac death, myocardial infarction, and heart failure, was evaluated at 24 months of follow-up. RESULTS At baseline, NG patients had a lower percentage of LAD endothelial dysfunction compared with pre-DM patients (P < 0.05). The pre-DM patients had a higher percentage of endothelial LAD dysfunction as compared with the pre-DM metformin patients (P < 0.05). At the 24th month of follow-up, MACE was higher in pre-DM versus NG (P < 0.05). In pre-DM metformin patients, MACE was lower compared with pre-DM patients (P < 0.05). CONCLUSIONS Metformin therapy may reduce the high risk of cardiovascular events in pre-DM patients by reducing coronary endothelial dysfunction.
Background and objectives To explore cognitive, EEG, and MRI features in COVID-19 survivors up to 10 months after hospital discharge. Methods Adult patients with a recent diagnosis of COVID-19 and reporting subsequent cognitive complaints underwent neuropsychological assessment and 19-channel-EEG within 2 months (baseline, N = 49) and 10 months (follow-up, N = 33) after hospital discharge. A brain MRI was obtained for 36 patients at baseline. Matched healthy controls were included. Using eLORETA, EEG regional current densities and linear lagged connectivity values were estimated. Total brain and white matter hyperintensities (WMH) volumes were measured. Clinical and instrumental data were evaluated between patients and controls at baseline, and within patient whole group and with/without dysgeusia/hyposmia subgroups over time. Correlations among findings at each timepoint were computed. Results At baseline, 53% and 28% of patients showed cognitive and psychopathological disturbances, respectively, with executive dysfunctions correlating with acute-phase respiratory distress. Compared to healthy controls, patients also showed higher regional current density and connectivity at delta band, correlating with executive performances, and greater WMH load, correlating with verbal memory deficits. A reduction of cognitive impairment and delta band EEG connectivity were observed over time, while psychopathological symptoms persisted. Patients with acute dysgeusia/hyposmia showed lower improvement at memory tests than those without. Lower EEG delta band at baseline predicted worse cognitive functioning at follow-up. Discussion COVID-19 patients showed interrelated cognitive, EEG, and MRI abnormalities 2 months after hospital discharge. Cognitive and EEG findings improved at 10 months. Dysgeusia and hyposmia during acute COVID-19 were related with increased vulnerability in memory functions over time. Supplementary Information The online version contains supplementary material available at 10.1007/s00415-022-11047-5.
BackgroundNo proper data on prognosis and management of type-2 diabetic ST elevation myocardial infarction (STEMI) patients with culprit obstructive lesion and multivessel non obstructive coronary stenosis (Mv-NOCS) exist. We evaluated the 12-months prognosis of Mv-NOCS-diabetics with first STEMI vs.to non-diabetics, and then Mv-NOCS-diabetics previously treated with incretin based therapy vs. a matched cohort of STEMI-Mv-NOCS never treated with such therapy.Methods1088 Patients with first STEMI and Mv-NOCS were scheduled for the study. Patients included in the study were categorized in type 2 diabetics (n 292) and non-diabetics (n 796). Finally, we categorized diabetics in current-incretin-users (n 76), and never-incretin-users (n 180). The primary end point was all cause deaths, cardiac deaths, and major adverse cardiac events (MACE) at 12 months of follow up.ResultsThe study results evidenced higher percentage of all cause deaths (2.2% vs. 1.1%, p value 0.05), cardiac deaths (1.6% vs. 0.5%, p value 0.045), and MACE (12.9% vs. n 5.9%), p value 0.001) in diabetic vs. no diabetic patients at 12 months follow up. Among diabetic patients, the current vs never-incretin-users, did not present a significant difference about all cause of deaths, and cardiac deaths through 12-months. The MACE rate at 1 year was 7.4% in diabetic incretin-users STEMI Mv-NOCS patients vs. 12.9% in diabetic never-incretin-users STEMI-Mv-NOCS patients (p value 0.04). In a risk-adjusted hazard analysis, MACE through 12 months were lower in diabetic STEMI-Mv NOCS incretin-users vs never-incretin-users patients (HR 0.513, CI [0.292–0.899], p 0.021). Consequently, lower levels of glucagon-like peptide 1(GLP-1) were predictive of MACE at follow up (HR 1.528, CI [1.059–2.204], p 0.024).ConclusionIn type 2 diabetic patients with STEMI-Mv-NOCS, we observed higher incidence of 1-year mortality and adverse cardiovascular outcomes, as compared to non-diabetic STEMI-Mv-NOCS patients. In diabetic patients, never-incretin-users have worse prognosis as compared to current-incretin-users.Trail registration Clinical trial number: NCT03312179, name of registry: clinicaltrialgov, URL: clinicalltrialgov.com, date of registration: September 2017, date of enrollment first participant: September 2009
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