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Importance: Understanding of the genetics of accessory atrioventricular pathways (APs) and affiliated arrhythmias is limited., Objective: To investigate the genetics of APs and affiliated arrhythmias., Design, Setting, and Participants: This was a genome-wide association study (GWAS) of APs, defined by International Classification of Diseases (ICD) codes and/or confirmed by electrophysiology (EP) study. Genome-wide significant AP variants were tested for association with AP-affiliated arrhythmias: paroxysmal supraventricular tachycardia (PSVT), atrial fibrillation (AF), ventricular tachycardia, and cardiac arrest. AP variants were also tested in data on other heart diseases and measures of cardiac physiology. Individuals with APs and control individuals from Iceland (deCODE Genetics), Denmark (Copenhagen Hospital Biobank, Danish Blood Donor Study, and SupraGen/the Danish General Suburban Population Study [GESUS]), the US (Intermountain Healthcare), and the United Kingdom (UK Biobank) were included. Time of phenotype data collection ranged from January 1983 to December 2022. Data were analyzed from August 2022 to January 2024., Exposures: Sequence variants., Main Outcomes and Measures: Genome-wide significant association of sequence variants with APs., Results: The GWAS included 2310 individuals with APs (median [IQR] age, 43 [28-57] years; 1252 [54.2%] male and 1058 [45.8%] female) and 1 206 977 control individuals (median [IQR] year of birth, 1955 [1945-1970]; 632 888 [52.4%] female and 574 089 [47.6%] male). Of the individuals with APs, 909 had been confirmed in EP study. Three common missense variants were associated with APs, in the genes CCDC141 (p.Arg935Trp: adjusted odds ratio [aOR], 1.37; 95% CI, 1.24-1.52, and p.Ala141Val: aOR, 1.55; 95% CI 1.34-1.80) and SCN10A (p.Ala1073Val: OR, 1.22; 95% CI, 1.15-1.30). The 3 variants associated with PSVT and the SCN10A variant associated with AF, supporting an effect on AP-affiliated arrhythmias. All 3 AP risk alleles were associated with higher heart rate and shorter PR interval, and have reported associations with chronotropic response., Conclusions and Relevance: Associations were found between sequence variants and APs that were also associated with risk of PSVT, and thus likely atrioventricular reentrant tachycardia, but had allele-specific associations with AF and conduction disorders. Genetic variation in the modulation of heart rate, chronotropic response, and atrial or atrioventricular node conduction velocity may play a role in the risk of AP-affiliated arrhythmias. Further research into CCDC141 could provide insights for antiarrhythmic therapeutic targeting in the presence of an AP.

Importance: Recurrent pericarditis is a treatment challenge and often a debilitating condition. Drugs inhibiting interleukin 1 cytokines are a promising new treatment option, but their use is based on scarce biological evidence and clinical trials of modest sizes, and the contributions of innate and adaptive immune processes to the pathophysiology are incompletely understood., Objective: To use human genomics, transcriptomics, and proteomics to shed light on the pathogenesis of pericarditis., Design, Setting, and Participants: This was a meta-analysis of genome-wide association studies of pericarditis from 5 countries. Associations were examined between the pericarditis-associated variants and pericarditis subtypes (including recurrent pericarditis) and secondary phenotypes. To explore mechanisms, associations with messenger RNA expression (cis-eQTL), plasma protein levels (pQTL), and CpG methylation of DNA (ASM-QTL) were assessed. Data from Iceland (deCODE genetics, 1983-2020), Denmark (Copenhagen Hospital Biobank/Danish Blood Donor Study, 1977-2022), the UK (UK Biobank, 1953-2021), the US (Intermountain, 1996-2022), and Finland (FinnGen, 1970-2022) were included. Data were analyzed from September 2022 to August 2023., Exposure: Genotype., Main Outcomes and Measures: Pericarditis., Results: In this genome-wide association study of 4894 individuals with pericarditis (mean [SD] age at diagnosis, 51.4 [17.9] years, 2734 [67.6%] male, excluding the FinnGen cohort), associations were identified with 2 independent common intergenic variants at the interleukin 1 locus on chromosome 2q14. The lead variant was rs12992780 (T) (effect allele frequency [EAF], 31%-40%; odds ratio [OR], 0.83; 95% CI, 0.79-0.87; P = 6.67 × 10-16), downstream of IL1B and the secondary variant rs7575402 (A or T) (EAF, 45%-55%; adjusted OR, 0.89; 95% CI, 0.85-0.93; adjusted P = 9.6 × 10-8). The lead variant rs12992780 had a smaller odds ratio for recurrent pericarditis (0.76) than the acute form (0.86) (P for heterogeneity = .03) and rs7575402 was associated with CpG methylation overlapping binding sites of 4 transcription factors known to regulate interleukin 1 production: PU.1 (encoded by SPI1), STAT1, STAT3, and CCAAT/enhancer-binding protein β (encoded by CEBPB)., Conclusions and Relevance: This study found an association between pericarditis and 2 independent sequence variants at the interleukin 1 gene locus. This finding has the potential to contribute to development of more targeted and personalized therapy of pericarditis with interleukin 1-blocking drugs.

Background: There is a need for a feasible tool to assess the risk of frailty prior to surgery. We aimed to identify the ratio of abnormal results for three clinically applicable screening tools to assess the risk of frailty, and their association with adverse outcomes in a cohort of elderly surgical patients., Methods: In this prospective pilot study, patients ≥65 years undergoing preoperative evaluation for elective surgery were included and subjected to three frailty screening tests; Program of Research to Integrate Services for the Maintenance of Autonomy 7-item questionnaire (PRISMA7), Timed Up and Go (TUG), and Clock Drawing Test (CDT). The primary outcome was the incidence of abnormal testing, and secondary outcomes were the association between abnormal tests and mortality, readmission, delirium, surgical complications and non-home discharge., Results: Out of 99 patients, 41%, 37%, and 43% had abnormal PRISMA7, TUG, and CDT screening, respectively. Postoperative delirium was more likely to occur in patients with abnormal TUG screening (19% vs. 3%, p = .011) and CDT (17% vs. 2%, p = .019). When analyzing screening tool combinations, patients with abnormal PRISMA7 and TUG had a higher rate of non-home discharge (38% vs. 17%, p = .029); and patients with abnormal TUG and CDT had a higher rate of postoperative delirium (25% vs. 3%, p = .006) and any surgical complication (58% vs. 38%, p = .037); and patients with abnormal results from all three tools had a higher rate of postoperative delirium (21% vs. 5%, p = .045) and non-home discharge (42% vs. 18%, p = .034)., Conclusion: Approximately 40% of elderly surgical patients have abnormal PRISMA7, TUG, and CDT screening tests for frailty, and they are associated individually or in combination with increased risk of adverse postoperative outcomes. The results will aid in designing studies to further risk-stratify patients at risk of frailty and attempt to modify associated outcomes., (© 2022 Acta Anaesthesiologica Scandinavica Foundation.)

Introduction: The interRAI Emergency Department-Screener (ED-screener) is a risk stratification instrument incorporating functional and social aspects to identify older adults in EDs. The aim was to assess the construct validity and utility of the ED-screener in comparison with more established instruments., Methods: The ED-screener, Triage Risk Screening Tool (TRST) and Identification of Seniors at Risk (ISAR) were administered to older ED-patients. Construct validity was assessed by correlation with TRST and ISAR. The ED-screener scores that corresponded to the established cut-offs for ISAR and TRST were assessed with linear regression. The sensitivity and specificity of the ED-screener for mortality at 4-months were calculated., Results: Two hundred patients were included (mean age 78.5 years, 44% male). Majority (85%) lived at home, 43% lived alone and 53% received home care. The scores of 3.02 and 3.01 on ED-screener corresponded to the cut-off score of 2 on the other instruments. The correlation of the ED-screener with ISAR and TRST was 0.56 and 0.41 respectively. A score of 3 on the ED-screener was 100% sensitive and 28% specific for 4-month mortality., Conclusion: These findings provide support for the construct validity of the ED-screener and its ability to predict outcomes in its intended setting., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Background: the European Union of Medical Specialists (UEMS-GMS) recommendations for training in Geriatric Medicine were published in 1993. The practice of Geriatric Medicine has developed considerably since then and it has therefore become necessary to update these recommendations., Methods: under the auspices of the UEMS-GMS, the European Geriatric Medicine Society (EuGMS) and the European Academy of Medicine of Ageing (EAMA), a group of experts, representing all member states of the respective bodies developed a new framework for education and training of specialists in Geriatric Medicine using a modified Delphi technique. Thirty-two expert panel members from 30 different countries participated in the process comprising three Delphi rounds for consensus. The process was led by five facilitators., Results: the final recommendations include four different domains: 'General Considerations' on the structure and aim of the syllabus as well as quality indicators for training (6 sub-items), 'Knowledge in patient care' (36 sub-items), 'Additional Skills and Attitude required for a Geriatrician' (9 sub-items) and a domain on 'Assessment of postgraduate education: which items are important for the transnational comparison process' (1 item)., Conclusion: the current publication describes the development of the new recommendations endorsed by UEMS-GMS, EuGMS and EAMA as minimum training requirements to become a geriatrician at specialist level in EU member states., (© The Author(s) (2019). Published by Oxford University Press on behalf of the British Geriatrics Society.)

Introduction: It is important to know the effective dose from computed tomography (CT) examinations. The aim of this study was to evaluate the effective dose from pediatric CT examinations in Iceland., Materials and Method: For all pediatric CT exams (children < 18 years) performed during one year (1.2.2016 till 1.2.2017), data on age, examination type and dose length product was retrospectively collected from the Landspitali University Hospital's archives, as was the total number of CT examinations. The ratio of pediatric CT exams and the frequency of examination types were calculated and, for the three most common examinations, the effective dose and mean dose length product were calculated for five age groups., Results: The total number of pediatric CT examinations was 662, 3,6% of all the CT examinations performed. The three most common pediatric CT examinations were head (40,3%), abdomen (15,6%) and thorax (10,3%). The mean effective dose in those was, in the above order: for children < 4 months: 5,3/4,9/3,0 mSv; 4 months to < 3 years: 4,2/5,5/1,9 mSv; 3 years to < 8 years: 2,7/ 3,4/1,0 mSv; 8 years to < 15 years: 3,2/4,4/1,0 mSv and 15 years to < 18 years: 2,1/6,5/3,3 mSv. The mean dose length product was above European diagnostic reference levels in most examination types and age groups., Conclusion: Possibilities for lower effective doses from pediatric CT examinations should be explored. For that purpose, the use of size specific dose estimates is recommended.

Germline missense mutations affecting a single BRCA2 allele predispose humans to cancer. Here we identify a protein-targeting mechanism that is disrupted by the cancer-associated mutation, BRCA2(D2723H), and that controls the nuclear localization of BRCA2 and its cargo, the recombination enzyme RAD51. A nuclear export signal (NES) in BRCA2 is masked by its interaction with a partner protein, DSS1, such that point mutations impairing BRCA2-DSS1 binding render BRCA2 cytoplasmic. In turn, cytoplasmic mislocalization of mutant BRCA2 inhibits the nuclear retention of RAD51 by exposing a similar NES in RAD51 that is usually obscured by the BRCA2-RAD51 interaction. Thus, a series of NES-masking interactions localizes BRCA2 and RAD51 in the nucleus. Notably, BRCA2(D2723H) decreases RAD51 nuclear retention even when wild-type BRCA2 is also present. Our findings suggest a mechanism for the regulation of the nucleocytoplasmic distribution of BRCA2 and RAD51 and its impairment by a heterozygous disease-associated mutation.

Messenger RNA (mRNA) export from the nucleus is essential for eukaryotic gene expression. Here we identify a transcript-selective nuclear export mechanism affecting certain human transcripts, enriched for functions in genome duplication and repair, controlled by inositol polyphosphate multikinase (IPMK), an enzyme catalyzing inositol polyphosphate and phosphoinositide turnover. We studied transcripts encoding RAD51, a protein essential for DNA repair by homologous recombination (HR), to characterize the mechanism underlying IPMK-regulated mRNA export. IPMK depletion or catalytic inactivation selectively decreases RAD51 protein abundance and the nuclear export of RAD51 mRNA, thereby impairing HR. Recognition of a sequence motif in the untranslated region of RAD51 transcripts by the mRNA export factor ALY requires IPMK. Phosphatidylinositol (3,4,5)-trisphosphate (PIP3), an IPMK product, restores ALY recognition in IPMK-depleted cell extracts, suggesting a mechanism underlying transcript selection. Our findings implicate IPMK in a transcript-selective mRNA export pathway controlled by phosphoinositide turnover that preserves genome integrity in humans., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Tetraploidy and aneuploidy can be caused by cell division errors and are frequently observed in many human carcinomas. We have recently reported delayed cytokinesis in primary human fibroblasts from BRCA2 mutation carriers, implying a function for the BRCA2 tumour suppressor in completion of cell division. Here, we address ploidy aberrations in breast tumours derived from BRCA2 germline mutation carriers. Ploidy aberrations were evaluated from flow cytometry histograms on selected breast tumour samples (n=236), previously screened for local BRCA mutations. The ploidy between BRCA2-mutated (n=71) and matched sporadic (n=165) cancers was compared. Differences in ploidy distribution were examined with respect to molecular tumour subtypes, previously defined by immunohistochemistry on tissue microarray sections. Tetraploidy was significantly 3 times more common in BRCA2 breast cancers than sporadic. However, no differences were found in the overall ploidy distribution between BRCA2-mutation carriers and non-carriers. In BRCA2 cancers, tetraploidy was associated with luminal characteristics. The increased frequency of tetraploidy in BRCA2 associated cancers may be linked to cell division errors, particularly cytokinesis. Additionally, tetraploidy emerges predominantly in BRCA2 breast cancers displaying luminal rather than triple-negative phenotypes., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Imaging of live cells was carried out using evanescent-wave excitation on a polymer waveguide chip. Integrated waveguide-based interferometric light modulators were fabricated in order to demonstrate on-chip control of excitation light, e.g., for time-lapse fluorescence microscopy. When combined with a sensitive high-resolution imaging system, the integrated waveguide-excitation platform provides an ideal method of near-surface studies of live cells, where photobleaching and/or phototoxicity effects are of critical concern.

We present detailed characterization of a unique high-index-contrast integrated optical polymer waveguide platform where the index of the cladding material is closely matched to that of water. Single-mode waveguides designed to operate across a large part of the visible spectrum have been fabricated and waveguide properties, including mode size, bend loss and evanescent coupling have been modeled using effective-index approximation, finite-element and finite-difference time domain methods. Integrated components such as directional couplers for wavelength splitting and ring resonators for refractive-index or temperature sensing have been modeled, fabricated and characterized. The waveguide platform described here is applicable to a wide range of biophotonic applications relying on evanescent-wave sensing or excitation, offering a high level of integration and functionality. The technology is biocompatible and suitable for wafer-level mass production.

Background: In cytokinesis, when the cleavage furrow has been formed, the two centrioles in each daughter cell separate. It has been suggested that the centrioles facilitate and regulate cytokinesis to some extent. It has been postulated that termination of cytokinesis (abscission) depends on the migration of a centriole to the intercellular bridge and then back to the cell center. To investigate the involvement of centrioles in cytokinesis, we monitored the movements of centrioles in three mammalian epithelial cell lines, HeLa, MCF 10A, and the p53-deficient mouse mammary tumor cell line KP-7.7, by time-lapse imaging. Centrin1-EGFP and alpha-Tubulin-mCherry were co-expressed in the cells to visualize respectively the centrioles and microtubules., Results: Here we report that separated centrioles that migrate from the cell pole are very mobile during cytokinesis and their movements can be characterized as 1) along the nuclear envelope, 2) irregular, and 3) along microtubules forming the spindle axis. Centriole movement towards the intercellular bridge was only seen occasionally and was highly cell-line dependent., Conclusions: These findings show that centrioles are highly mobile during cytokinesis and suggest that the repositioning of a centriole to the intercellular bridge is not essential for controlling abscission. We suggest that centriole movements are microtubule dependent and that abscission is more dependent on other mechanisms than positioning of centrioles.

Background: Inherited mutations in the tumour suppressor gene BRCA2 greatly increase the risk of developing breast, ovarian and other types of cancers. So far, most studies have focused on the role of BRCA-pathways in the maintenance of genomic stability. In this study we investigated the potential role of the BRCA2 protein in cytokinesis in unmodified primary human fibroblast carrying a heterozygous mutation in the BRCA2 gene., Methods: Cell divisions were monitored with time lapse live-cell imaging. BRCA2 mRNA expression levels in BRCA2+/- and BRCA2+/+ cells were quantified with quantitative real-time polymerase chain reaction (qRT-PCR). To investigate the localization of the BRCA2 protein during cytokinesis, immunofluorescence staining using antibody directed against BRCA2 was carried out. Immunofluorescence staining was performed directly after live-cell imaging and cells with delayed cytokinesis, of which the co-ordinates were saved, were automatically repositioned and visualized., Results: We demonstrate that unmodified primary human fibroblasts derived from heterozygous BRCA2 mutation carriers show significantly prolonged cytokinesis. A Subset of the BRCA2+/- cells had delayed cytokinesis (40 min or longer) making the mean cell division time 6 min longer compared with BRCA2+/+ cells, 33 min versus 27 min, respectively. Lower BRCA2 mRNA expression levels were observed in the BRCA2 heterozygous samples compared with the BRCA2 wild type samples. The BRCA2 protein localizes and accumulates to the midbody during cytokinesis, and no difference was detected in distribution and localization of the protein between BRCA2+/- and BRCA2+/+ samples or cells with delayed cytokinesis and normal division time., Conclusions: The delayed cytokinesis phenotype of the BRCA2 heterozygous cells and localization of the BRCA2 protein to the midbody confirms that BRCA2 plays a role in cytokinesis. Our observations indicate that in a subset of cells the presence of only one wild type BRCA2 allele is insufficient for efficient cytokinesis.