Search

Left atrial perforation is a known complication following pulmonary vein catheter ablation. Our case of a 62-year-old female underwent urgent surgery for repair of left atrium perforation with left pleural effusion as a late complication after multiple transcatheter radiofrequency pulmonary vein ablations for persistent atrial fibrillation., (© 2020 Wiley Periodicals LLC.)

Competency-based medical education (CBME) curricula are becoming increasingly common in graduate medical education. Put simply, CBME is focused on educational outcomes, is independent of methods and time, and is composed of achievable competencies. 1 In spite of widespread uptake, there remains much to learn about implementing CBME at the program level. Leveraging the collective experience of program leaders at Queen's University, where CBME simultaneously launched across 29 specialty programs in 2017, this paper leverages change management theory to provide a short summary of how program leaders can navigate the successful preparation, launch, and initial implementation of CBME within their residency programs., Competing Interests: Conflicts of interest: There are no conflicts of interest to disclose., (© 2020 Dagnone, Taylor, Acker, Bouchard, Chamberlain, DeJong, Dos-Santos, Fleming, Hall, Jaeger, Mann, Trier, McEwen; licensee Synergies Partners.)

Human papillomavirus (HPV)-related oropharyngeal squamous cell carcinoma (OPSCC) exhibits a different composition of epigenetic alterations. In this study, we identified differentially methylated regions (DMRs) with potential utility in screening for HPV-positive OPSCC. Genome wide DNA methylation was measured using methyl-CpG binding domain protein-enriched genome sequencing (MBD-seq) in 50 HPV-positive OPSCC tissues and 25 normal tissues. Fifty-one DMRs were defined with maximal methylation specificity to cancer samples. The Cancer Genome Atlas (TCGA) methylation array data was used to evaluate the performance of the proposed candidates. Supervised hierarchical clustering of 51 DMRs found that HPV-positive OPSCC had significantly higher DNA methylation levels compared to normal samples, and non-HPV-related head and neck squamous cell carcinoma (HNSCC). The methylation levels of all top 20 DNA methylation biomarkers in HPV-positive OPSCC were significantly higher than those in normal samples. Further confirmation using quantitative methylation specific PCR (QMSP) in an independent set of 24 HPV-related OPSCCs and 22 controls showed that 16 of the 20 candidates had significant higher methylation levels in HPV-positive OPSCC samples compared with controls. One candidate, OR6S1, had a sensitivity of 100%, while 17 candidates (KCNA3, EMBP1, CCDC181, DPP4, ITGA4, BEND4, ELMO1, SFMBT2, C1QL3, MIR129-2, NID2, HOXB4, ZNF439, ZNF93, VSTM2B, ZNF137P and ZNF773) had specificities of 100%. The prediction accuracy of the 20 candidates rang from 56.2% to 99.8% by receiver operating characteristic analysis. We have defined 20 highly specific DMRs in HPV-related OPSCC, which can potentially be applied to molecular-based detection tests and improve disease management., (© 2018 UICC.)

Spontaneous coronary artery dissection is an uncommon nonatherosclerotic cause of acute coronary syndrome. It usually occurs in young women and is often associated with fibromuscular dysplasia, connective tissue diseases, and pregnancy or postpartum states. We present a case of a Syrian woman with a history of grand multiparity and recent miscarriage who presented with non-ST-elevation myocardial infarction and was found to have multivessel spontaneous coronary artery dissection and severe left ventricular dysfunction., (Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.)

Objectives: This study sought to determine whether volume loading alters the left atrial appendage (LAA) dimensions in patients undergoing percutaneous LAA closure., Background: Percutaneous LAA closure is increasingly performed in patients with atrial fibrillation and contraindications to anticoagulation, to lower their stroke and systemic embolism risk. The safety and efficacy of LAA closure relies on accurate device sizing, which necessitates accurate measurement of LAA dimensions. LAA size may change with volume status, and because patients are fasting for these procedures, intraprocedural measurements may not be representative of true LAA size., Methods: Thirty-one consecutive patients undergoing percutaneous LAA closure who received volume loading during the procedure were included in this study. After an overnight fast and induction of general anesthesia, patients had their LAA dimensions (orifice and depth) measured by transesophageal echocardiography before and after 500 to 1,000 ml of intravenous normal saline, aiming for a left atrial pressure >12 mm Hg., Results: Successful implantation of LAA closure device was achieved in all patients. The average orifice size of the LAA at baseline was 20.5 mm at 90°, and 22.5 mm at 135°. Following volume loading, the average orifice size of the LAA increased to 22.5 mm at 90°, and 23.5 mm at 135°. The average increase in orifice was 1.9 mm (p < 0.0001). The depth of the LAA also increased by an average of 2.5 mm after volume loading (p < 0.0001)., Conclusions: Intraprocedural volume loading with saline increased the LAA orifice and depth dimensions during LAA closure. Operators should consider optimizing the left atrial pressure with volume loading before final device sizing., (Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Aims: Left atrial appendage (LAA) device imaging after endovascular closure is important to assess for device thrombus, residual leak, positioning, surrounding structures, and pericardial effusion. Cardiac CT angiography (CCTA) is well suited to assess these non-invasively., Methods and Results: We report our consecutive series of non-valvular atrial fibrillation patients who underwent CCTA post-LAA closure with Amplatzer Cardiac Plug (ACP), Amulet (second generation ACP), or WATCHMAN devices. Patients underwent CCTA typically 1-6 months post-implantation. Prospective cardiac-gated CCTA was performed with Toshiba 320-detector or Siemens 2nd generation 128-slice dual-source scanners, and images interpreted with VitreaWorkstation™. GFR <30 mL/min/1.73 m(2) was an exclusion. We assessed for device thrombus, residual LAA leak, device embolization, position, pericardial effusion, optimal implantation, and device lobe dimensions. Forty-five patients underwent CCTA at median 97 days post-LAA closure (18 ACP, 9 Amulet, 18 WATCHMAN). Average age was 75.5 ± 8.9 years, mean CHADS2 score 3.1 ± 1.3, and CHADS-VASc score 4.9 ± 1.6. All had contraindications to oral anticoagulation. Post-procedure, 41 (91.1%) were discharged on DAPT. There was one device embolization (ACP, successfully retrieved percutaneously) and one thrombus (WATCHMAN, resolved with 3 months of warfarin). There were two pericardial effusions, both pre-existing and not requiring intervention. Residual leak (patency) was seen in 28/44 (63.6%), and the mechanisms of leak were readily identified by CCTA (off-axis device, gaps at orifice, or fabric leak). Mean follow-up was 1.2 ± 1.1year, with no death, stroke, or systemic embolism., Conclusion: CCTA appears to be a feasible alternative to transoesophageal echocardiography for post-LAA device surveillance to evaluate for device thrombus, residual leak, embolization, position, and pericardial effusion., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.)

As the population ages and cardiovascular disease becomes more prevalent, an increasing number of patients are receiving implantable cardioverter-defibrillators (ICDs). When these patients present to the emergency department, it is imperative that physicians are not only aware of the possible underlying medical issues that may have precipitated their admission but should also have a good understanding of the potential interactions that any medical intervention may have on the patient's device. We discuss a case in which a patient known to have an ICD in situ was transcutaneously paced for the management of bradycardia, leading to an unnecessary shock.

Despite their prevalence and importance, the genome sequences of loblolly pine, Norway spruce, and white spruce, three ecologically and economically important conifer species, are just becoming available to the research community. Following the completion of these large assemblies, annotation efforts will be undertaken to characterize the reference sequences. Accurate annotation of these ancient genomes would be aided by a comprehensive repeat library; however, few studies have generated enough sequence to fully evaluate and catalog their non-genic content. In this paper, two sets of loblolly pine genomic sequence, 103 previously assembled BACs and 90,954 newly sequenced and assembled fosmid scaffolds, were analyzed. Together, this sequence represents 280 Mbp (roughly 1% of the loblolly pine genome) and one of the most comprehensive studies of repetitive elements and genes in a gymnosperm species. A combination of homology and de novo methodologies were applied to identify both conserved and novel repeats. Similarity analysis estimated a repetitive content of 27% that included both full and partial elements. When combined with the de novo investigation, the estimate increased to almost 86%. Over 60% of the repetitive sequence consists of full or partial LTR (long terminal repeat) retrotransposons. Through de novo approaches, 6,270 novel, full-length transposable element families and 9,415 sub-families were identified. Among those 6,270 families, 82% were annotated as single-copy. Several of the novel, high-copy families are described here, with the largest, PtPiedmont, comprising 133 full-length copies. In addition to repeats, analysis of the coding region reported 23 full-length eukaryotic orthologous proteins (KOGS) and another 29 novel or orthologous genes. These discoveries, along with other genomic resources, will be used to annotate conifer genomes and address long-standing questions about gymnosperm evolution.

Background: Although second generation sequencing (2GS) technologies allow re-sequencing of previously gold-standard-sequenced genomes, whole genome shotgun sequencing and de novo assembly of large and complex eukaryotic genomes is still difficult. Availability of a genome-wide physical map is therefore still a prerequisite for whole genome sequencing for genomes like barley. To start such an endeavor, large insert genomic libraries, i.e. Bacterial Artificial Chromosome (BAC) libraries, which are unbiased and representing deep haploid genome coverage, need to be ready in place., Result: Five new BAC libraries were constructed for barley (Hordeum vulgare L.) cultivar Morex. These libraries were constructed in different cloning sites (HindIII, EcoRI, MboI and BstXI) of the respective vectors. In order to enhance unbiased genome representation and to minimize the number of gaps between BAC contigs, which are often due to uneven distribution of restriction sites, a mechanically sheared library was also generated. The new BAC libraries were fully characterized in depth by scrutinizing the major quality parameters such as average insert size, degree of contamination (plate wide, neighboring, and chloroplast), empty wells and off-scale clones (clones with <30 or >250 fragments). Additionally a set of gene-based probes were hybridized to high density BAC filters and showed that genome coverage of each library is between 2.4 and 6.6 X., Conclusion: BAC libraries representing >20 haploid genomes are available as a new resource to the barley research community. Systematic utilization of these libraries in high-throughput BAC fingerprinting should allow developing a genome-wide physical map for the barley genome, which will be instrumental for map-based gene isolation and genome sequencing.

We present a global comparison of differences in content of segmental duplication between human and chimpanzee, and determine that 33% of human duplications (> 94% sequence identity) are not duplicated in chimpanzee, including some human disease-causing duplications. Combining experimental and computational approaches, we estimate a genomic duplication rate of 4-5 megabases per million years since divergence. These changes have resulted in gene expression differences between the species. In terms of numbers of base pairs affected, we determine that de novo duplication has contributed most significantly to differences between the species, followed by deletion of ancestral duplications. Post-speciation gene conversion accounts for less than 10% of recent segmental duplication. Chimpanzee-specific hyperexpansion (> 100 copies) of particular segments of DNA have resulted in marked quantitative differences and alterations in the genome landscape between chimpanzee and human. Almost all of the most extreme differences relate to changes in chromosome structure, including the emergence of African great ape subterminal heterochromatin. Nevertheless, base per base, large segmental duplication events have had a greater impact (2.7%) in altering the genomic landscape of these two species than single-base-pair substitution (1.2%).

Human chromosome 16 features one of the highest levels of segmentally duplicated sequence among the human autosomes. We report here the 78,884,754 base pairs of finished chromosome 16 sequence, representing over 99.9% of its euchromatin. Manual annotation revealed 880 protein-coding genes confirmed by 1,670 aligned transcripts, 19 transfer RNA genes, 341 pseudogenes and three RNA pseudogenes. These genes include metallothionein, cadherin and iroquois gene families, as well as the disease genes for polycystic kidney disease and acute myelomonocytic leukaemia. Several large-scale structural polymorphisms spanning hundreds of kilobase pairs were identified and result in gene content differences among humans. Whereas the segmental duplications of chromosome 16 are enriched in the relatively gene-poor pericentromere of the p arm, some are involved in recent gene duplication and conversion events that are likely to have had an impact on the evolution of primates and human disease susceptibility.

Chromosome 19 has the highest gene density of all human chromosomes, more than double the genome-wide average. The large clustered gene families, corresponding high G + C content, CpG islands and density of repetitive DNA indicate a chromosome rich in biological and evolutionary significance. Here we describe 55.8 million base pairs of highly accurate finished sequence representing 99.9% of the euchromatin portion of the chromosome. Manual curation of gene loci reveals 1,461 protein-coding genes and 321 pseudogenes. Among these are genes directly implicated in mendelian disorders, including familial hypercholesterolaemia and insulin-resistant diabetes. Nearly one-quarter of these genes belong to tandemly arranged families, encompassing more than 25% of the chromosome. Comparative analyses show a fascinating picture of conservation and divergence, revealing large blocks of gene orthology with rodents, scattered regions with more recent gene family expansions and deletions, and segments of coding and non-coding conservation with the distant fish species Takifugu.

The sex chromosome constitution of the silkworm, Bombyx mori, is ZW in the female and ZZ in the male. Very little molecular information is available about the Z chromosome in Lepidoptera, although the topic is interesting because of the absence of gene dosage compensation in this chromosome. We constructed a 320-kb BAC contig around the Bmkettin gene on the Z chromosome in Bombyx and determined its nucleotide sequence by the shotgun method. We found 13 novel protein-coding sequences in addition to Bmkettin. All the transposable elements detected in the region were truncated, and no LTR retrotransposons were found, in stark contrast to the situation on the W chromosome. In this 320-kb region, four genes for muscle proteins (Bmkettin, Bmtitin1, Bmtitin2, and Bmprojectin) are clustered, together with another gene (Bmmiple) on the Z chromosome in B. mori; their orthologs are also closely linked on chromosome 3 in Drosophila, suggesting a partial synteny. Real-time RT-PCR experiments demonstrated that transcripts of 13 genes of the 14 Z-linked genes found accumulated in larger amounts in males than in female moths, indicating the absence of gene dosage compensation. The implications of these findings for the evolution and function of the Z chromosome in Lepidoptera are discussed.

Aim: To examine the relation between the type of choroidal neovascularisation (CNV) in the first eye and age related maculopathy (ARM) severity in the fellow eye., Methods: Colour fundus photographs and fluorescein angiograms from 67 subjects with a clinical diagnosis of CNV in one eye were scrutinised. CNV was classified as wholly classic, predominantly classic, minimally classic, or occult based on the proportion of classic leakage within the lesion. ARM changes in the fellow eye were assigned a severity stage using the system described by the Rotterdam Eye Study. Logistic regression analysis was employed to examine the association between CNV subtype and ARM stage., Results: Of subjects with classic or predominantly classic CNV in the first eye 78% exhibited least no or early ARM features in the fellow eye. By contrast, 85% of subjects with minimally classic or occult CNV in the first eye exhibited more advanced ARM features in the fellow eye. Kruskall-Wallis one way ANOVA by ranks showed that this was highly significant (p = 0.002). Logistic regression analysis showed that as the proportion of occult CNV increased in the first eye, fellow eyes of subjects in this category were more likely to have been assigned to a higher ARM stage (p = 0.019). The area occupied by the CNV in the first eye also influenced severity of ARM changes in the fellow eye., Conclusion: The type and extent of CNV in the first affected eye has a distinct relation to ARM severity in the fellow eye. Fellow eyes of subjects with minimally classic or occult CNV in the first affected eye show widespread ARM changes suggestive of retinal pigment epithelial dysfunction. These findings suggest that classic CNV may be focal disease while occult CNV is essentially a more widespread retinal pigment epithelial disorder.

We have investigated aromatase and the inducible cyclooxygenase COX-2 expression using immunocytochemistry in tumors of a series of patients with advanced breast cancer treated with aromatase inhibitors. Aromatase was expressed in 58/102 breast cancers. This is similar to the percentage previously reported for aromatase activity. Interestingly, aromatase was expressed in a variety of cell types, including tumor, stromal, adipose, and endothelial cells. Since prostaglandin E2 is known to regulate aromatase gene expression and is the product of COX-2, an enzyme frequently overexpressed in tumors, immunocytochemistry was performed on the tissue sections using a polyclonal antibody to COX-2. Aromatase was strongly correlated (P<0.001) with COX-2 expression. These results suggest that PGE2 produced by COX-2 in the tumor may be important in stimulating estrogen synthesis in the tumor and surrounding tissue. No correlation was observed between aromatase or COX-2 expression and the response of the patients to aromatase inhibitor treatment. However, only 13 patients responded. Nine of these patients were aromatase positive. Although similar to responses in other studies, this low response rate to second line treatment suggests that tumors of most patients were no longer sensitive to the effects of estrogen. Recent clinical studies suggest that greater responses occur when aromatase inhibitors are used as first line treatment. In the intratumoral aromatase mouse model, expression of aromatase in tumors is highly correlated with increased tumor growth. First line treatment with letrozole was effective in all animals treated and was more effective than tamoxifen in suppressing tumor growth. Letrozole was also effective in tumors failing to respond to tamoxifen, consistent with clinical findings. In addition, the duration of response was significantly longer with the aromatase inhibitor than with tamoxifen, suggesting that aromatase inhibitors may offer better control of tumor growth than this antiestrogen.

We have constructed a 1-Mb contig in human chromosomal band 11p15.5, a region implicated in the etiology of several embryonal tumors, including Wilms tumor, and in Beckwith-Wiedemann syndrome. Cosmid, P1, PAC, and BAC clones were characterized by NotI/SalI digestion and hybridized to a variety of probes to generate a detailed physical map that extends from D11S517 to L23MRP. Included in the map are the CARS, NAP2, p57/KIP2, KVLQT1, ASCL2, TH, INS, IGF2, H19, and L23MRP genes as well as end probes isolated from PACs. The TAPA1 gene, whose protein product can transmit an antiproliferative signal, was also localized in the contig. However, Northern blot analysis demonstrated that its expression did not correlate with tumorigenicity in G401 Wilms tumor hybrids, suggesting that TAPA1 is not responsible for the tumor suppression associated with 11p15.5. Genomic clones were used as probes in FISH analysis to map the breakpoints from three Beckwith-Wiedemann syndrome patients and a rhabdoid tumor. Interestingly, each of the breakpoints disrupts the KVLQT1 gene, which is spread over a 400-kb region of the contig. Since 11p15.5 contains several genes with imprinted expression and one or more tumor suppressor genes, our contig and map provide a framework for characterizing this intriguing genetic environment.

The gene for spinocerebellar ataxia type 2 (SCA2) has been mapped to 12q24.1. A 1.1-megabase contig in the candidate region was assembled in P1 artificial chromosome and bacterial artificial chromosome clones. Using this contig, we identified a CAG trinucleotide repeat with CAA interruptions that was expanded in patients with SCA2. In contrast to other unstable trinucleotide repeats, this CAG repeat was not highly polymorphic in normal individuals. In SCA2 patients, the repeat was perfect and expanded to 36-52 repeats. The most common disease allele contained (CAG)37, one of the shortest expansions seen in a CAG expansion syndrome. The repeat occurs in the 5'-coding region of SCA2 which is a member of a novel gene family.

The mouse gene U2 auxiliary factor binding protein related sequence (U2afbp-rs) has previously been shown to be genomically imprinted with monoallelic expression from the paternal allele. To determine if the human homologue is imprinted and contains conserved structural features which regulate imprinting, we isolated genomic clones from a human P1-derived artificial chromosome (PAC) library that map to human chromosome 5q22-31, a region syntenic to the proximal portion of mouse chromosome 11 where U2afbp-rs resides. A genomic subclone was isolated which contained an open reading frame with high homology to the mouse gene. This subclone also maintained the intronless character of the mouse gene. A KpnI polymorphism within the open reading frame of the gene was found to occur in 21% (8/38) of the alleles tested from human placental tissue samples. RT-PCR analysis of human placentas using the KpnI polymorphism to determine the parental origin of the alleles indicates biallelic expression of the human chromosome 5 U2AFBPL gene.

Fifty-nine NotI linking clones have been isolated from a flow-sorted chromosome 22 cosmid library and mapped using fluorescence in situ hybridization and/or a panel of somatic cell hybrids. Fourteen clones map to the short arm of chromosome 22, 31 to the long arm, and 9 to other chromosomes; 5 clones could not be unambiguously mapped. To identify potentially informative genetic markers, the chromosome 22 clones were screened for poly(CA) sequences; 24 positively hybridizing clones, 10 on the long arm and 14 on the short arm, were identified. These clones will be useful for constructing a long-range restriction map of chromosome 22 and may facilitate the cloning of chromosome 22 genes.

In order to permit detailed characterization of meningioma cases showing deletions within chromosomal band 22q12 and further systematically clone genes located within this region, we established a genomic YAC and cosmid contig which encompasses a region in excess of 1000 kb of 22q12. The YAC contig consists of 6 YAC clones arranged into 5 overlapping steps covering more than 1100 kb. Two corresponding cosmid contigs consisting of 40 steps of overlapping groups of cosmids encompasses 900-1000 kb. This set of genomic clones provides a detailed physical map of this part of chromosome 22 and constitutes a basis for the isolation and characterization of genes that may be located within this chromosomal region. Employing the exon-amplification method on two cosmids from the contig, we cloned a novel, anonymous gene, pK1.3, which potentially encodes a protein of 683 amino acids with a predicted molecular weight of of 78.5 kD. Its 2.7 kb mRNA is expressed ubiquitously. We estimated the genomic size of this gene to 100-150 kb, and it is located in the immediate centromeric vicinity of the neurofibromatosis 2 (NF2) tumor suppressor gene.

"A state-space model is developed which provides estimates of decrements in a dynamic environment. The model integrates the actual unfolding experience and a priori or Bayesian views of the rates. The estimates of present rates and predicted future rates are continually updated and associated standard errors have simple expressions. The model is described and applied in the context of mortality estimation but it should prove useful in other actuarial applications. The approach is particularly suitable for dynamic environments where data are scarce and updated parameter estimates are required on a regular basis. To illustrate the method it is used to monitor the unfolding mortality experience of the retired lives under an actual pension plan.", (excerpt)

The role of genomic alterations in mutagenesis induced by ionizing radiation has been the subject of considerable speculation. By Southern blotting analysis we show here that 9 of 55 (approximately 1/6) gamma-ray-induced mutants at the adenine phosphoribosyl transferase (aprt) locus of Chinese hamster ovary (CHO) cells have a detectable genomic rearrangement. These fall into two classes: intragenic deletions and chromosomal rearrangements. In contrast, no major genomic alterations were detected among 67 spontaneous mutants, although two restriction site loss events were observed. Three gamma-ray-induced mutants were found to be intragenic deletions; all may have identical break-points. The remaining six gamma-ray-induced mutants demonstrating a genomic alteration appear to be the result of chromosomal rearrangements, possibly translocation or inversion events. None of the remaining gamma-ray-induced mutants showed any observable alteration in blotting pattern indicating a substantial role for point mutation in gamma-ray-induced mutagenesis at the aprt locus.

Early and late complications of central venous catheterization were investigated in 488 consecutive catheters, 389 introduced in the subclavian vein by a percutaneous puncture technique, 84 by a cut down technique of the cephalic vein, and 15 by a peel away technique. Care and introduction of the catheters was controlled by the parenteral nutrition team in 239 cases. Immediate and late complications were found using both the puncture and venous cut down techniques, but immediate complications differed in the two groups due to the different methods of insertion. The rate of catheter related sepsis (CRS) did not differ significantly when the group under control of the nutrition team was compared with the group without nutritional control (5.9 vs. 6%). The rate of CRS was 1 CRS/220.7 days of therapy in the puncture group and 1 CRS/342.2 days of therapy in the venous cut down group. Catheter tips and blood were cultured from both CRS and non-CRS patients, and the micro-organisms identified. Catheters were withdrawn, under supervision of the nutrition team, for a number of reasons including death, thrombosis, and technical problems, but suspicion of CRS accounted for a high percentage of withdrawals (18% in the puncture group, 16.6% in the venous cut down group). It is suggested that, when CRS is suspected, removal of the catheter should be delayed until all other possibilities have been investigated.

Streptomyces griseus ATCC 10137 synthesizes about 1 IU of L-asparaginase/100 ml of a 4% peptone medium. The enzyme has a pH optimum of 8.5 which is comparable to that of the L-asparaginase derived from Escherichia coli which has antitumor properties.