Search

[Display omitted] [ABSTRACT FROM AUTHOR]

The aim of this study was to characterize the feasibility of coronary angiography (CA) and percutaneous coronary intervention (PCI) in acute settings among patients who have undergone transcatheter aortic valve replacement (TAVR). Impaired coronary access after TAVR may be challenging and particularly in acute settings could have deleterious consequences. In this international registry, data from patients with prior TAVR requiring urgent or emergent CA were retrospectively collected. A total of 449 patients from 25 sites with acute coronary syndromes (89.1%) and other acute cardiovascular situations (10.9%) were included. Success rates were high for CA of the right coronary artery (98.3%) and left coronary artery (99.3%) and were higher among patients with short stent-frame prostheses (SFPs) than in those with long SFPs for CA of the right coronary artery (99.6% vs 95.9%; P = 0.005) but not for CA of the left coronary artery (99.7% vs 98.7%; P = 0.24). PCI of native coronary arteries was successful in 91.4% of cases and independent of valve type (short SFP 90.4% vs long SFP 93.4%; P = 0.44). Guide engagement failed in 6 patients, of whom 3 underwent emergent coronary artery bypass grafting and another 3 died in the hospital. Among patients requiring revascularization of native vessels, independent predictors of 30-day all-cause mortality were prior diabetes, cardiogenic shock, and failed PCI but not valve type or success of coronary engagement. CA or PCI after TAVR in acute settings is usually successful, but selective coronary engagement may be more challenging in the presence of long SFPs. Among patients requiring PCI, prior diabetes, cardiogenic shock, and failed PCI were predictors of early mortality. [Display omitted] [ABSTRACT FROM AUTHOR]

Objective It has been reported that balloon aortic valvuloplasty immediately before transfemoral or transapical transcatheter aortic valve implantation has mostly little to no clinical value. We aimed to provide data on the need for balloon aortic valvuloplasty in patients undergoing transaortic transcatheter aortic valve implantation. Methods Patients undergoing transaortic transcatheter aortic valve implantation with the Edwards SAPIEN XT (Nyon, Switzerland) or 3 transcatheter heart valve were prospectively included at 18 sites across Europe. In the present analysis, we compare the periprocedural and 30-day outcomes of patients undergoing conventional (+ balloon aortic valvuloplasty) versus direct (− balloon aortic valvuloplasty) transaortic transcatheter aortic valve implantation. Results Of the 300 patients enrolled, 222 underwent conventional and 78 underwent direct transaortic transcatheter aortic valve implantation. Peak and mean transvalvular gradients were improved in both groups with no significant difference between groups. Procedural duration, contrast agent volume, and requirement for postdilation were also comparable. A trend toward fewer periprocedural complications was evident in the direct group (3.9% vs 11.3%; P = .053), with significantly lower rates of permanent pacemaker implantation (0% vs 5.0%; P = .034). Balloon aortic valvuloplasty omission had no significant effect on any of the 30-day safety and efficacy outcomes, including Valve Academic Research Consortium-2 composite end points (early safety events: 22.7% vs 17.4%, odds ratio, 1.17, 95% confidence interval, 0.53-2.62; clinical efficacy events: 20.5% vs 18.7%, odds ratio, 1.14, 95% confidence interval, 0.51-2.55). Conclusions For many patients, balloon aortic valvuloplasty predilation seems to have little clinical value in transaortic transcatheter aortic valve implantation using a balloon expandable transcatheter valve and may result in a higher rate of periprocedural complications, particularly in terms of permanent pacemaker implantation. [ABSTRACT FROM AUTHOR]

Objectives The Registry of the Utilization of the TAo-TAVR approach using the Edwards SAPIEN Valve (ROUTE) was established to assess the effectiveness and safety of the use of transaortic (TAo) access for transcatheter aortic valve replacement (TAVR) procedures ( NCT01991431 ). Background TAVR represents an alternative to surgical valve replacement in high-risk patients. Whereas the transfemoral access route is used commonly as the first-line approach, transapical access is an option for patients not suitable for transfemoral treatment mainly due to anatomic conditions. TAo-TAVR has been shown to be a viable alternative surgical access route; however, only limited data on its effectiveness and safety has been published. Methods ROUTE is a multicenter, international, prospective, observational registry; data were collected from 18 centers across Europe starting in February 2013. Patients having severe calcific aortic stenosis were documented if they were scheduled to undergo TAo-TAVR using an Edwards SAPIEN XT or a SAPIEN 3 valve. The primary endpoint was 30-day mortality. Secondary endpoints were intraprocedural or in hospital and 30-day complication rates. Results A total of 301 patients with a mean age of 81.7 ± 5.9 years and an Society of Thoracic Surgeons score of 9.0 ± 7.6% were included. Valve success was documented in 96.7%. The 30-day mortality was 6.1% (18/293) (procedure-related mortality: 3.1%; 9 of 293). The Valve Academic Research Consortium-2 defined complications included myocardial infarction (1.0%), stroke (1.0%), transient ischemic attack (0.3%), major vascular complications (3.4%), life-threatening bleeding (3.4%), and acute kidney injury (9.5%). In 3.3% of patients, paravalvular regurgitation was classified as moderate or severe (10 of 300). Twenty-six patients (8.8%) required permanent pacemaker implantation. Conclusions TAo access for TAVR seems to be a safe alternative to the transapical procedure. [ABSTRACT FROM AUTHOR]

During the last 15 years, the perception of the cardiac z-disc has undergone substantial changes. Initially viewed as a structural component at the lateral boundaries of the sarcomere, the cardiac z-disc has increasingly become recognized as a nodal point in cardiomyocyte signal transduction and disease. This minireview thus focuses on novel components and recent developments in z-disc biology and their role in cardiac signaling and disease. [ABSTRACT FROM AUTHOR]

Activation of the phosphatase calcineurin and its downstream targets, transcription factors of the NFAT family, results in cardiomyocyte hypertrophy. Recently, it has been shown that the dual specificity tyrosine (Y) phosphorylation-regulated kinase 1A (DYRK1A) is able to antagonize calcineurin signaling by directly phosphorylating NFATs. We thus hypothesized that DYRK1A might modulate the hypertrophic response of cardiomyocytes. In a model of phenylephrine-induced hypertrophy, adenovirus-mediated overexpression of DYKR1A completely abrogated the hypertrophic response and significantly reduced the expression of the natriuretic peptides ANF and BNP. Furthermore, DYRK1A blunted cardiomyocyte hypertrophy induced by overexpression of constitutively active calcineurin and attenuated the induction of the hypertrophic gene program. Conversely, knockdown of DYRK1A, utilizing adenoviruses encoding for a specific synthetic miRNA, resulted in an increase in cell surface area accompanied by up-regulation of ANF-mRNA. Similarly, treatment of cardiomyocytes with harmine, a specific inhibitor of DYRK1A, revealed cardiomyocyte hypertrophy on morphological and molecular level. Moreover, constitutively active calcineurin led to robust induction of an NFAT-dependent luciferase reporter, whereas DYRK1A attenuated calcineurin-induced reporter activation in cardiomyocytes. Conversely, both knockdown and pharmacological inhibition of DYRK1A significantly augmented the effect of calcineurin in this assay. In summary, we identified DYRK1A as a novel negative regulator of cardiornyocyte hypertrophy. Mechanistically, this effect appears to be mediated via inhibition of NFAT transcription factors. [ABSTRACT FROM AUTHOR]

In addition to regulating cell motility, contractility, and cytokinesis, the actin cytoskeleton plays a critical role in the regulation of transcription and gene expression. We have previously identified a novel muscle-specific actin-binding protein, STARS (striated muscle activator of Rho signaling), which directly binds actin and stimulates serum-response factor (SRF)-dependent transcription. To further dissect the STARS/SRF pathway, we performed a yeast two-hybrid screen of a skeletal muscle cDNA library using STARS as bait, and we identified two novel members of the ABLIM protein family, ABLIM-2 and -3, as STARS-interacting proteins. ABLIM-1, which is expressed in retina, brain, and muscle tissue, has been postulated to function as a tumor suppressor. ABLIM-2 and -3 display distinct tissue-specific expression patterns with the highest expression levels in muscle and neuronal tissue. Moreover, these novel ABLIM proteins strongly bind F-actin, are localized to actin stress fibers, and synergistically enhance STARS-dependent activation of SRF. Conversely, knockdown of endogenous ABLIM expression utilizing small interfering RNA significantly blunted SRF-dependent transcription in C2C12 skeletal muscle cells. These findings suggest that the members of the novel ABLIM protein family may serve as a scaffold for signaling modules of the actin cytoskeleton and thereby modulate transcription. [ABSTRACT FROM AUTHOR]

Abstract: We performed cytogenetic analyses of 8 renal oncocytomas to identify chromosomal regions involved in the tumorigenesis of oncocytomas. All cases showed chromosomal findings corresponding to established cytogenetic subsets of renal oncocytomas: 3 cases with normal karyotypes, 1 case with rearrangement of 11q, and 4 cases with losses of chromosome 14. In the latter cytogenetic subgroup, monosomy 14 was additionally accompanied by either monosomy 1 in 2 cases or loss of 1p in a third case, providing insights in the cytogenetic evolution of this subgroup. [Copyright &y& Elsevier]

Histones are the major protein component of chromatin. Except H4, all histone classes consist of several subtypes. The H3 family includes two replacement histone genes, H3.3A and H3.3B, which both encode the same protein and are expressed independently from the cell cycle. Since the two genes encode an identical protein, we analyzed whether they are differentially expressed. Therefore we cloned, sequenced and characterized the regulatory structures of the H3.3A gene and compared these with the corresponding regions in the H3.3B gene. In contrast to the H3.3B promoter, the promoter region of the H3.3A gene revealed neither a TATA nor any CCAAT boxes but an initiator element and several SP1 binding sequence motifs within an overall GC-rich sequence. Northern blot analysis of RNA from six human cell lines revealed that every cell line expressed each of the H3 isoform genes H3.1, H3.3A and H3.3B. In contrast, analysis of total RNA from human tissues showed a differential expression of the H3 isoform genes. The H3.3 genes are essentially only expressed in adult tissue, whereas the H3.1 gene is transcribed just in fetal tissue. The functional relevance of the elements identified by sequence analysis was established using a reporter gene assay with deletion constructs of the H3.3A promoter. In this assay a 256 bp fragment was sufficient for the full promoter activity and three promoter segments, each containing SP1 binding motifs, contribute to the H3.3A gene expression. The possible functional relevance of the differences between the two H3.3 genes in structure and expression is discussed. [Copyright &y& Elsevier]

Malignant peripheral nerve sheath tumors (MPNST) are soft tissue sarcomas occurring frequently in patients with neurofibromatosis 1. We present three fully karyotyped cases of MPNST revealing aberrant near-triploid karyotypes. In all three cases we found deletions of chromosome arms or chromosomes 1p, 10q, 9, and 15, as well as gain of chromosome 7 in two NF1-associated cases and gain of chromosome 8 in an NF1-associated and a sporadic case. The chromosomal region of the NF1 gene was cytogenetically unchanged in all cases, whereas two MPNST cases showed losses of the region 22q harboring the locus of the NF2 gene. [Copyright &y& Elsevier]

Myocardial failure is associated with adverse remodeling, including loss of cardiomyocytes, hypertrophy, and alterations in cell–cell contacts. Striatin-interacting phosphatase and kinase (STRIPAK) complexes and their mammalian STE20-like kinase 4 (Mst4) have been linked to development of different diseases. The role and targets of Mst4 in cardiomyocytes have not been investigated yet. Multitissue immunoblot experiments show highly enriched Mst4 expression in rodent hearts. Analyses of human biopsy samples from patients suffering from dilated cardiomyopathy revealed that Mst4 is upregulated (5- to 8-fold p < 0.001) compared with nonfailing controls. Increased abundance of Mst4 could also be detected in mouse models of cardiomyopathy. We confirmed that Mst4 interacts with STRIPAK components in neonatal rat ventricular cardiomyocytes, indicating that STRIPAK is present in the heart. Immunofluorescence stainings and molecular interaction studies revealed thatMst4 is localized to the intercalated disc and interacts with several intercalated disc proteins. Overexpression of Mst4 in cardiomyocytes results in hypertrophy compared with controls. In adult rat cardiomyocytes, Mst4 overexpression increases cellular and sarcomeric fractional shortening (p < 0.05), indicating enhanced contractility. Overexpression of Mst4 also inhibits apoptosis shown by reduction of cleaved caspase3 (−69%, p < 0.0001), caspase7 (−80%, p < 0.0001), and cleaved Parp1 (−27%, p < 0.001). To elucidate potential Mst4 targets, we performed phosphoproteomics analyses in neonatal rat cardiomyocytes after Mst4 overexpression and inhibition. The results revealed target candidates of Mst4 at the intercalated disc. We identified Mst4 as a novel cardiac kinase that is upregulated in cardiomyopathy-regulating cardiomyocyte growth and survival. [ABSTRACT FROM AUTHOR]

We have previously shown that dysbindin is a potent inducer of cardiomyocyte hypertrophy via activation of Rho-dependent serum-response factor (SRF) signaling. We have now performed a yeast two-hybrid screen using dysbindin as bait against a cardiac cDNA library to identify the cardiac dysbindin interactome. Among several putative binding proteins, we identified tripartite motif-containing protein 24 (TRIM24) and confirmed this interaction by co-immunoprecipitation and co-immunostaining. Another tripartite motif (TRIM) family protein, TRIM32, has been reported earlier as an E3 ubiquitin ligase for dysbindin in skeletal muscle. Consistently, we found that TRIM32 also degraded dysbindin in neonatal rat ventricular cardiomyocytes as well. Surprisingly, however, TRIM24 did not promote dysbindin decay but rather protected dysbindin against degradation by TRIM32. Correspondingly, TRIM32 attenuated the activation of SRF signaling and hypertrophy due to dysbindin, whereas TRIM24 promoted these effects in neonatal rat ventricular cardiomyocytes. This study also implies that TRIM32 is a key regulator of cell viability and apoptosis in cardiomyocytes via simultaneous activation of p53 and caspase- 3/-7 and inhibition of X-linked inhibitor of apoptosis. In conclusion, we provide here a novel mechanism of post-translational regulation of dysbindin and hypertrophy via TRIM24 and TRIM32 and show the importance of TRIM32 in cardiomyocyte apoptosis in vitro. [ABSTRACT FROM AUTHOR]

The intercalated disc (ID) is a "hot spot" for heart disease, as several ID proteins have been found mutated in cardiomyopathy. Myozap is a recent addition to the list of ID proteins and has been implicated in serum-response factor signaling. To elucidate the cardiac consequences of targeted deletion of myozap in vivo, we generated myozap-null mutant (Mzp-/-) mice. Although Mzp-/- mice did not exhibit a baseline phenotype, increased biomechanical stress due to pressure overload led to accelerated cardiac hypertrophy, accompaniedby"super"-induction of fetal genes, including natriuretic peptides A and B (Nppa/Nppb). Moreover, Mzp-/- mice manifested a severe reduction of contractile function, signs of heart failure, and increased mortality. Expression of other ID proteins like N-cadherin, desmoplakin, connexin-43, and ZO-1 was significantly perturbed upon pressure overload, underscored by disorganization of the IDs in Mzp-/- mice. Exploration of the molecular causes of enhanced cardiac hypertrophy revealed significant activation of β-catenin/GSK-3β signaling, whereas MAPK and MKL1/serum-response factor pathways were inhibited. In summary, myozap is required for proper adaptation to increased biomechanical stress. In broader terms, our data imply an essential function of the ID in cardiac remodeling beyond a mere structural role and emphasize the need for a better understanding of this molecular structure in the context of heart disease. [ABSTRACT FROM AUTHOR]

Summary: Although considerable knowledge exists on the tumor biology of lung cancer, there is still a need to assess molecular events for the clinical management of the disease. We studied the pattern of chromosomal imbalances in 45 non-small cell lung carcinomas (NSCLC) by comparative genomic hybridization (CGH) and correlated the results with clinicopathological features including immunohistochemical (IHC) expression of the epidermal growth factor receptor (EGFR). Twenty-one tumors were squamous cell carcinomas (SCC) and 24 non-squamous cell lung carcinomas (NSCC) comprising 9 adenocarcinomas (ADC), 9 large cell carcinomas (LCC), 4 sarcomatoid carcinomas and 2 adenosquamous carcinomas. The mean number of individual imbalances was 7.1 for SCC (mean gains, 3.8; mean losses, 3.4) and 6.4 for NSCC (mean gains, 4.5; mean losses, 1.9). Several individual imbalances correlated significantly with increasing number of imbalances, that were +1q, −3p, +3q, −5q, −8p, +8q, +7p, +12p, and +14q. Altogether, the most frequent imbalances were +3q (49%), +5p (49%), −5q (36%), +8q (29%), −8p (24%), −3p (22%), +7p (22%), +12p (22%), +14q (20%), +18p (20%), +1q (18%), and +7q (18%). Among these, +3q and +18p correlated significantly with SCC, and +5p and +14q with NSCC. Remarkably, overlapping imbalances included +3q26, +7p11 in SCC and +1q21, +3q24, +12p11, and +14q12 in NSCC. EGFR expression was higher in SCC than in NSCC and correlated with +3q in the entire series. In addition, +12p correlated significantly with disease progress with the exception of nodal involvement in NSCC as well as with disease progress, regardless of nodal involvement, in the entire series. In conclusion, the present study contributes to the molecular biological characterization of NSCLC histological subtypes and through evaluation of molecular events to the recently emergent focus on novel markers for lung cancer treatment. [Copyright &y& Elsevier]