Intellectual disability (ID) disorders are genetically and phenotypically highly heterogeneous and present a major challenge in clinical genetics and medicine. Although many genes involved in ID have ...been identified, the etiology is unknown in most affected individuals. Moreover, the function of most genes associated with ID remains poorly characterized. Evidence is accumulating that the control of gene transcription through epigenetic modification of chromatin structure in neurons has an important role in cognitive processes and in the etiology of ID. However, our understanding of the key molecular players and mechanisms in this process is highly fragmentary. Here, we identify a chromatin-modification module that underlies a recognizable form of ID, the Kleefstra syndrome phenotypic spectrum (KSS). In a cohort of KSS individuals without mutations in EHMT1 (the only gene known to be disrupted in KSS until now), we identified de novo mutations in four genes, MBD5, MLL3, SMARCB1, and NR1I3, all of which encode epigenetic regulators. Using Drosophila, we demonstrate that MBD5, MLL3, and NR1I3 cooperate with EHMT1, whereas SMARCB1 is known to directly interact with MLL3. We propose a highly conserved epigenetic network that underlies cognition in health and disease. This network should allow the design of strategies to treat the growing group of ID pathologies that are caused by epigenetic defects.
Genetic causes for autosomal recessive forms of dilated cardiomyopathy (DCM) are only rarely identified, although they are thought to contribute considerably to sudden cardiac death and heart ...failure, especially in young children. Here, we describe 11 young patients (5-13 years) with a predominant presentation of dilated cardiomyopathy (DCM). Metabolic investigations showed deficient protein N-glycosylation, leading to a diagnosis of Congenital Disorders of Glycosylation (CDG). Homozygosity mapping in the consanguineous families showed a locus with two known genes in the N-glycosylation pathway. In all individuals, pathogenic mutations were identified in DOLK, encoding the dolichol kinase responsible for formation of dolichol-phosphate. Enzyme analysis in patients' fibroblasts confirmed a dolichol kinase deficiency in all families. In comparison with the generally multisystem presentation in CDG, the nonsyndromic DCM in several individuals was remarkable. Investigation of other dolichol-phosphate dependent glycosylation pathways in biopsied heart tissue indicated reduced O-mannosylation of alpha-dystroglycan with concomitant functional loss of its laminin-binding capacity, which has been linked to DCM. We thus identified a combined deficiency of protein N-glycosylation and alpha-dystroglycan O-mannosylation in patients with nonsyndromic DCM due to autosomal recessive DOLK mutations.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Background and purpose
There are concerns that the coronavirus disease 2019 (COVID-19) outbreak negatively affects the quality of care for acute cardiovascular conditions. We assessed the impact of ...the COVID-19 outbreak on trends in hospital admissions and workflow parameters of acute stroke care in Amsterdam, The Netherlands.
Methods
We used data from the three hospitals that provide acute stroke care for the Amsterdam region. We compared two 7-week periods: one during the peak of the COVID-19 outbreak (March 16th–May 3th 2020) and one prior to the outbreak (October 21st–December 8th 2019). We included consecutive patients who presented to the emergency departments with a suspected stroke and assessed the change in number of patients as an incidence-rate ratio (IRR) using a Poisson regression analysis. Other outcomes were the IRR for stroke subtypes, change in use of reperfusion therapy, treatment times, and in-hospital complications.
Results
During the COVID-19 period, 309 patients presented with a suspected stroke compared to 407 patients in the pre-COVID-19 period (IRR 0.76 95%CI 0.65–0.88). The proportion of men was higher during the COVID-19 period (59% vs. 47%,
p
< 0.001). There was no change in the proportion of stroke patients treated with intravenous thrombolysis (28% vs. 30%,
p
= 0.58) or endovascular thrombectomy (11% vs 12%,
p
= 0.82) or associated treatment times. Seven patients (all ischemic strokes) were diagnosed with COVID-19.
Conclusion
We observed a 24% decrease in suspected stroke presentations during the COVID-19 outbreak, but no evidence for a decrease in quality of acute stroke care.
Background and Aims
Chronic hepatitis B (CHB) and nonalcoholic fatty liver disease are increasingly observed together in clinical practice, and development of nonalcoholic steatohepatitis (NASH) ...represents another leading cause of liver‐related morbidity and mortality. Our aims were to determine whether biopsy‐proven NASH impacts clinical outcomes in CHB patients and assess prognostic risk factors.
Approach and Results
CHB patients attending two tertiary centers in North America and Europe over 13 years with available clinical and biopsy data were included. Patients were categorized as no‐NASH or probable/definite NASH based on standardized histological assessment. Clinical events (death, decompensation, transplant, and hepatoma) were evaluated, and Kaplan‐Meier survival estimates and Cox proportional hazards regression were used to analyze the incidence of events. There were 1,089 CHB patients, classified as no‐NASH (n = 904, 83%) or NASH (n = 185, 17%), with 52 (6%) versus 27 (15%) experiencing outcome events during follow‐up, respectively. In the multivariable analysis adjusting for age, sex, hepatitis B e antigen serostatus, and diabetes, the presence of NASH and concomitant advanced fibrosis (AF) was significantly associated with clinical outcomes (hazard ratio 95% confidence interval, 4.8 2.6‐9.0, P < 0.01) when compared to absence of NASH and AF (reference). NASH and AF were associated with a greater risk of outcomes compared to AF (P = 0.01) or NASH alone (P < 0.01). Of the three histological determinants of NASH, ballooning and inflammation, but not steatosis, were independently associated with clinical outcomes (P < 0.05) in place of NASH. NASH was significantly associated with increased risk of hepatocellular carcinoma and death (P < 0.01) but not decompensation (P = 0.33).
Conclusions
In our large combined tertiary center cohort, patients with concomitant NASH and CHB had more AF and shorter time to development of liver‐related outcomes or death compared to patients with CHB alone. Among patients with AF, superimposed NASH predicted poorer clinical outcomes.
Intellectual disability (ID) is a clinically and genetically heterogeneous disorder, affecting 1-3% of the general population. Although research into the genetic causes of ID has recently gained ...momentum, identification of pathogenic mutations that cause autosomal recessive ID (ARID) has lagged behind, predominantly due to non-availability of sizeable families. Here we present the results of exome sequencing in 121 large consanguineous Pakistani ID families. In 60 families, we identified homozygous or compound heterozygous DNA variants in a single gene, 30 affecting reported ID genes and 30 affecting novel candidate ID genes. Potential pathogenicity of these alleles was supported by co-segregation with the phenotype, low frequency in control populations and the application of stringent bioinformatics analyses. In another eight families segregation of multiple pathogenic variants was observed, affecting 19 genes that were either known or are novel candidates for ID. Transcriptome profiles of normal human brain tissues showed that the novel candidate ID genes formed a network significantly enriched for transcriptional co-expression (P<0.0001) in the frontal cortex during fetal development and in the temporal-parietal and sub-cortex during infancy through adulthood. In addition, proteins encoded by 12 novel ID genes directly interact with previously reported ID proteins in six known pathways essential for cognitive function (P<0.0001). These results suggest that disruptions of temporal parietal and sub-cortical neurogenesis during infancy are critical to the pathophysiology of ID. These findings further expand the existing repertoire of genes involved in ARID, and provide new insights into the molecular mechanisms and the transcriptome map of ID.
Schizophrenia is associated with lower intelligence and poor educational performance relative to the general population. This is, to a lesser degree, also found in first-degree relatives of ...schizophrenia patients. It is unclear whether bipolar disorder I (BD-I) patients and their relatives have similar lower intellectual and educational performance as that observed in schizophrenia.
This cross-sectional study investigated intelligence and educational performance in two outpatient samples 494 BD-I patients, 952 schizophrenia spectrum (SCZ) patients, 2231 relatives of BD-I and SCZ patients, 1104 healthy controls and 100 control siblings. Mixed-effects and regression models were used to compare groups on intelligence and educational performance.
BD-I patients were more likely to have completed the highest level of education (odds ratio 1.88, 95% confidence interval 1.66-2.70) despite having a lower IQ compared to controls (β = -9.09, S.E. = 1.27, p < 0.001). In contrast, SCZ patients showed both a lower IQ (β = -15.31, S.E. = 0.86, p < 0.001) and lower educational levels compared to controls. Siblings of both patient groups had significantly lower IQ than control siblings, but did not differ on educational performance. IQ scores did not differ between BD-I parents and SCZ parents, but BD-I parents had completed higher educational levels.
Although BD-I patients had a lower IQ than controls, they were more likely to have completed the highest level of education. This contrasts with SCZ patients, who showed both intellectual and educational deficits compared to healthy controls. Since relatives of BD-I patients did not demonstrate superior educational performance, our data suggest that high educational performance may be a distinctive feature of bipolar disorder patients.
Study objective Mechanical chest compression devices have been developed to facilitate continuous delivery of high-quality cardiopulmonary resuscitation (CPR). Despite promising hemodynamic data, ...evidence on clinical outcomes remains inconclusive. With the completion of 3 randomized controlled trials, we conduct a meta-analysis on the effect of in-field mechanical versus manual CPR on clinical outcomes after out-of-hospital cardiac arrest. Methods With a systematic search (PubMed, Web of Science, EMBASE, and the Cochrane Libraries), we identified all eligible studies (randomized controlled trials and nonrandomized studies) that compared a CPR strategy including an automated mechanical chest compression device with a strategy of manual CPR only. Outcome variables were survival to hospital admission, survival to discharge, and favorable neurologic outcome. Results Twenty studies (n=21,363) were analyzed: 5 randomized controlled trials and 15 nonrandomized studies, pooled separately. For survival to admission, the pooled estimate of the randomized controlled trials did not indicate a difference (odds ratio 0.94; 95% confidence interval 0.84 to 1.05; P =.24) between mechanical and manual CPR. In contrast, meta-analysis of nonrandomized studies demonstrated a benefit in favor of mechanical CPR (odds ratio 1.42; 95% confidence interval 1.21 to 1.67; P <.001). No interaction was found between the endorsed CPR guidelines (2000 versus 2005) and the CPR strategy ( P =.27). Survival to discharge and neurologic outcome did not differ between strategies. Conclusion Although there are lower-quality, observational data that suggest that mechanical CPR used at the rescuer’s discretion could improve survival to hospital admission, the cumulative high-quality randomized evidence does not support a routine strategy of mechanical CPR to improve survival or neurologic outcome. These findings are irrespective of the endorsed CPR guidelines during the study periods.
During development from childhood to adulthood the human brain undergoes considerable thinning of the cerebral cortex. Whether developmental cortical thinning is influenced by genes and if ...independent genetic factors influence different parts of the cortex is not known. Magnetic resonance brain imaging was done in twins at age 9 (N=190) and again at age 12 (N=125; 113 repeated measures) to assess genetic influences on changes in cortical thinning. We find considerable thinning of the cortex between over this three year interval (on average 0.05mm; 1.5%), particularly in the frontal poles, and orbitofrontal, paracentral, and occipital cortices. Cortical thinning was highly heritable at age 9 and age 12, and the degree of genetic influence differed for the various areas of the brain. One genetic factor affected left inferior frontal (Broca's area), and left parietal (Wernicke's area) thinning; a second factor influenced left anterior paracentral (sensory–motor) thinning. Two factors influenced cortical thinning in the frontal poles: one of decreasing influence over time, and another independent genetic factor emerging at age 12 in left and right frontal poles. Thus, thinning of the cerebral cortex is heritable in children between the ages 9 and 12. Furthermore, different genetic factors are responsible for variation in cortical thickness at ages 9 and 12, with independent genetic factors acting on cortical thickness across time and between various brain areas during childhood brain development.
►A large number of twins were scanned at age 9 (N=190) and again at 12 (N=125). ►Genetic factors acting on cortical thickness were independent across ages 9 and 12. ►Considerable thinning of the cortex was found between the ages 9 and 12. ►Cortical thinning was under genetic control. ►Genetic factors acting on cortical change were independent across brain areas.
A subject of ongoing debate among orthopedic surgeons is the importance of preserving the posterior cruciate ligament in total knee arthroplasty (TKA), but long-term survival studies are scarce. The ...aim of this study was to compare long-term survival rates, and clinical and radiological follow up of a double-blind randomized controlled trial comparing posterior cruciate-retaining (PCR) versus posterior-stabilizing (PS) implant design of an AGC TKA.
A total of 114 patients were included in the survival analysis (PCR n = 61; PS n = 53). Forty-five patients (PCR n = 25; PS n = 20) participated in the long-term follow up using patient-reported outcome measures (Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Short-Form Health Survey (SF-36) and Kujala score (measuring anterior knee pain)). Thirty-one patients were assessed with a physical test (Knee Society Score (KSS)) and radiographs.
Overall survival rate was 95.6% (PCR 98.4% vs. PS 92.5%), with five patients having a major revision (PCR n = 1 vs. PS n = 4, respectively). Satisfying outcome scores for both groups were described at on average 12-year follow up with no significant differences in KSS knee and function scores, WOMAC, SF-36, or Kujala scores between groups. Radiographically, there were no findings of femoral or tibial loosening or polyethylene wear in either group.
Good long-term survival rates were described for the PCR and the PS design of an AGC TKA. There were no significant differences in clinical and radiological outcomes between a PCR and a PS design 12 years postoperatively.
MED12 is a subunit of the Mediator multiprotein complex with a central role in RNA polymerase II transcription and regulation of cell growth, development, and differentiation. This might underlie the ...variable phenotypes in males carrying missense variants in MED12, including X-linked recessive Ohdo, Lujan, and FG syndromes.
By international matchmaking we assembled variant and clinical data on 18 females presenting with variable neurodevelopmental disorders (NDDs) and harboring de novo variants in MED12.
Five nonsense variants clustered in the C-terminal region, two splice variants were found in the same exon 8 splice acceptor site, and 11 missense variants were distributed over the gene/protein. Protein truncating variants were associated with a severe, syndromic phenotype consisting of intellectual disability (ID), facial dysmorphism, short stature, skeletal abnormalities, feeding difficulties, and variable other abnormalities. De novo missense variants were associated with a less specific, but homogeneous phenotype including severe ID, autistic features, limited speech and variable other anomalies, overlapping both with females with truncating variants as well as males with missense variants.
We establish de novo truncating variants in MED12 as causative for a distinct NDD and de novo missense variants as causative for a severe, less specific NDD in females.
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