High activation of STAT5A drives peripheral T-cell lymphoma and leukemia.

Recurrent gain-of-function mutations in the transcription factors STAT5A and much more in STAT5B were found in hematopoietic malignancies with the highest proportion in mature T- and natural killer-cell neoplasms (peripheral T-cell lymphoma, PTCL). No targeted therapy exists for these heterogeneous and often aggressive diseases. Given the shortage of models for PTCL, we mimicked graded STAT5A or STAT5B activity by expressing hyperactive Stat5a or STAT5B variants at low or high levels in the hematopoietic system of transgenic mice. Only mice with high activity levels developed a lethal disease resembling human PTCL. Neoplasia displayed massive expansion of CD8+ T cells and destructive organ infiltration. T cells were cytokine-hypersensitive with activated memory CD8+ T-lymphocyte characteristics. Histopathology and mRNA expression profiles revealed close correlation with distinct subtypes of PTCL. Pronounced STAT5 expression and activity in samples from patients with different subsets underline the relevance of JAK/STAT as a therapeutic target. JAK inhibitors or a selective STAT5 SH2 domain inhibitor induced cell death and ruxolitinib blocked T-cell neoplasia in vivo We conclude that enhanced STAT5A or STAT5B action both drive PTCL development, defining both STAT5 molecules as targets for therapeutic intervention.

Fully quantitative pixel-wise analysis of cardiovascular magnetic resonance perfusion improves discrimination of dark rim artifact from perfusion defects associated with epicardial coronary stenosis.

BACKGROUND: Dark rim artifacts in first-pass cardiovascular magnetic resonance (CMR) perfusion images can mimic perfusion defects and affect diagnostic accuracy for coronary artery disease (CAD). We evaluated whether quantitative myocardial blood flow (MBF) can differentiate dark rim artifacts from true perfusion defects in CMR perfusion. METHODS: Regadenoson perfusion CMR was performed at 1.5 T in 76 patients. Significant CAD was defined by quantitative invasive coronary angiography (QCA) ≥ 50% diameter stenosis. Non-significant CAD (NonCAD) was defined as stenosis by QCA < 50% diameter stenosis or computed tomographic coronary angiography (CTA) < 30% in all major epicardial arteries. Dark rim artifacts had study specific and guideline-based definitions for comparison purposes. MBF was quantified at the pixel-level and sector-level. RESULTS: In a NonCAD subgroup with dark rim artifacts, stress MBF was lower in the subendocardial than midmyocardial and epicardial layers (2.17 ± 0.61 vs. 3.06 ± 0.75 vs. 3.24 ± 0.80 mL/min/g, both p < 0.001) and was also 30% lower than in remote regions (2.17 ± 0.61 vs. 2.83 ± 0.67 mL/min/g, p < 0.001). However, subendocardial stress MBF in dark rim artifacts was 37-56% higher than in true perfusion defects (2.17 ± 0.61 vs. 0.95 ± 0.43 mL/min/g, p < 0.001). Absolute stress MBF differentiated CAD from NonCAD with an accuracy ranging from 86 to 89% (all p < 0.001) using pixel-level analyses. Similar results were seen at a sector level. CONCLUSION: Quantitative stress MBF is lower in dark rim artifacts than remote myocardium but significantly higher than in true perfusion defects. If confirmed in larger series, this approach may aid the interpretation of clinical stress perfusion exams. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT00027170 ; first posted 11/28/2001; updated 11/27/2017.

Quantitative pixel-wise measurement of myocardial blood flow: the impact of surface coil-related field inhomogeneity and a comparison of methods for its correction.

BACKGROUND: Surface coil-related field inhomogeneity potentially confounds pixel-wise quantitative analysis of perfusion CMR images. This study assessed the effect of surface coil-related field inhomogeneity on the spatial variation of pixel-wise myocardial blood flow (MBF), and assessed its impact on the ability of MBF quantification to differentiate ischaemic from remote coronary territories. Two surface coil intensity correction (SCIC) techniques were evaluated: 1) a proton density-based technique (PD-SCIC) and; 2) a saturation recovery steady-state free precession-based technique (SSFP-SCIC). METHODS: 26 subjects (18 with significant CAD and 8 healthy volunteers) underwent stress perfusion CMR using a motion-corrected, saturation recovery SSFP dual-sequence protocol. A proton density (PD)-weighted image was acquired at the beginning of the sequence. Surface coil-related field inhomogeneity was approximated using a third-order surface fit to the PD image or a pre-contrast saturation prepared SSFP image. The estimated intensity bias field was subsequently applied to the image series. Pixel-wise MBF was measured from mid-ventricular stress images using the two SCIC approaches and compared to measurements made without SCIC. RESULTS: MBF heterogeneity in healthy volunteers was higher using SSFP-SCIC (24.8 ± 4.1%) compared to PD-SCIC (20.8 ± 3.0%; p = 0.009), however heterogeneity was significantly lower using either SCIC technique compared to analysis performed without SCIC (36.2 ± 6.3%). In CAD patients, the difference in MBF between remote and ischaemic territories was minimal when analysis was performed without SCIC (0.06 ± 0.91 mL/min/kg), and was substantially lower than with either PD-SCIC (0.50 ± 0.63 mL/min/kg; p = 0.013) or with SSFP-SCIC (0.63 ± 0.89 mL/min/kg; p = 0.005). In 6 patients, MBF quantified without SCIC was artifactually higher in the stenosed coronary territory compared to the remote territory. PD-SCIC and SSFP-SCIC had similar differences in MBF between remote and ischaemic territories (p = 0.145). CONCLUSIONS: This study demonstrates that surface coil-related field inhomogeneity can confound pixel-wise MBF quantification. Whilst a PD-based SCIC led to a more homogenous correction than a saturation recovery SSFP-based technique, this did not result in an appreciable difference in the differentiation of ischaemic from remote coronary territories and thus either method could be applied.

Testing the language of German cerebral palsy patients with right hemispheric language organization after early left hemispheric damage.

Language functions are generally represented in the left cerebral hemisphere. After early (prenatally acquired or perinatally acquired) left hemispheric brain damage language functions may be salvaged by reorganization into the right hemisphere. This is different from brain lesions acquired in adulthood which normally lead to aphasia. Right hemispheric reorganized language (RL) is not associated with obvious language deficits. In this pilot study we compared a group of German-speaking patients with left hemispheric brain damage and RL with a group of matched healthy controls. The novel combination of reliable language lateralization as assessed by neuroimaging (functional magnetic resonance imaging) and specific linguistic tasks revealed significant differences between patients with RL and healthy controls in both language comprehension and production. Our results provide evidence for the hypothesis that RL is significantly different from normal left hemispheric language. This knowledge can be used to improve counselling of parents and to develop specific therapeutic approaches.

Accelerated management of patients with ST-segment elevation myocardial infarction in the ED.

PURPOSES: The objective of this study was to evaluate improvement opportunities in the emergency department for timely ST-segment elevation myocardial infarction management and evaluated the new process flow. BASIC PROCEDURES: In a prospective study, we compared time from door to cath laboratory before and after implementation of a new ST-segment elevation myocardial infarction (STEMI) protocol. The new protocol included a blend of strategies to reduce door to cath laboratory time. MAIN FINDINGS: We included 55 patients. After implementing a new STEMI protocol, we included 54 patients. Time to cath laboratory was 21 (interquartile range, 9-40) minutes before and 10 (interquartile range 5-25) minutes after initiation of the new protocol (P = .02). A door to cath laboratory time less than 15 minutes was reached in 36% of our patients in phase 1 and in 61% in phase 2 (odds ratio; 0.36, 95% confidence interval, 0.16-0.81; P = .01). PRINCIPAL CONCLUSION: Simple changes in organizational strategies resulted in a significantly faster care for patients with acute uncomplicated STEMI.

Local complement activation triggers neutrophil recruitment to the site of thrombus formation in acute myocardial infarction.

Atherosclerotic plaque rupture with subsequent mural thrombus formation is considered the main event compromising epicardial flow in acute myocardial infarction (AMI). However, the precise mechanisms underlying acute coronary occlusion are unknown. We compared the proteomic profiles of systemic plasma and plasma derived from the site of thrombus formation of patients with AMI by two-dimensional gel electrophoresis and ELISA. We identified a local activation of the complement system, with selective accumulation of the complement activator C-reactive protein (CRP) and the downstream complement effectors C3a and C5a. CRP in coronary thrombus co-localised with C1q and C3 immunoreactivities, suggesting classical complement activation. In vitro, coronary thrombus derived plasma enhanced neutrophil chemotaxis in a C5a dependent fashion. In vivo, neutrophil accumulation at the site of thrombus formation paralleled the time delay from symptom onset to first balloon inflation or aspiration, and was correlated with C5a and enzymatic infarct size. We present the first direct evidence for localised complement activation in acute coronary thrombi. Our data indicate that local complement effectors amplify the vascular occlusion process in AMI by enhanced neutrophil recruitment.

Establishing an in vivo model of canine prostate carcinoma using the new cell line CT1258.

BACKGROUND: Prostate cancer is a frequent finding in man. In dogs, malignant disease of the prostate is also of clinical relevance, although it is a less common diagnosis. Even though there are numerous differences in origin and development of the disease, man and dog share many similarities in the pathological presentation. For this reason, the dog might be a useful animal model for prostate malignancies in man.Although prostate cancer is of great importance in veterinary medicine as well as in comparative medicine, there are only few cell lines available. Thus, it was the aim of the present study to determine whether the formerly established prostate carcinoma cell line CT1258 is a suitable tool for in vivo testing, and to distinguish the growth pattern of the induced tumours. METHODS: For characterisation of the in vivo behaviour of the in vitro established canine prostate carcinoma cell line CT1258, cells were inoculated in 19 NOD.CB17-PrkdcScid/J (in the following: NOD-Scid) mice, either subcutaneously or intraperitoneally. After sacrifice, the obtained specimens were examined histologically and compared to the pattern of the original tumour in the donor. Cytogenetic investigation was performed. RESULTS: The cell line CT 1258 not only showed to be highly tumourigenic after subcutaneous as well as intraperitoneal inoculation, but also mimicked the behaviour of the original tumour. CONCLUSION: Tumours induced by inoculation of the cell line CT1258 resemble the situation in naturally occurring prostate carcinoma in the dog, and thus could be used as in vivo model for future studies.

Genomic characterisation, chromosomal assignment and in vivo localisation of the canine high mobility group A1 (HMGA1) gene.

BACKGROUND: The high mobility group A1 proteins (HMGA1a/HMGA1b) are highly conserved between mammalian species and widely described as participating in various cellular processes. By inducing DNA conformation changes the HMGA1 proteins indirectly influence the binding of various transcription factors and therefore effect the transcription regulation. In humans chromosomal aberrations affecting the HMGA1 gene locus on HSA 6p21 were described to be the cause for various benign mesenchymal tumours while high titres of HMGA1 proteins were shown to be associated with the neoplastic potential of various types of cancer. Interestingly, the absence of HMGA1 proteins was shown to cause insulin resistance and diabetes in humans and mice. Due to the various similarities in biology and presentation of human and canine cancers the dog has joined the common rodent animal model for therapeutic and preclinical studies. Accordingly, the canine genome was sequenced completely twice but unfortunately this could not solve the structure of canine HMGA1 gene. RESULTS: Herein we report the characterisation of the genomic structure of the canine HMGA1 gene consisting of 7 exons and 6 introns spanning in total 9524 bp, the in vivo localisation of the HMGA1 protein to the nucleus, and a chromosomal assignment of the gene by FISH to CFA12q11. Additionally, we evaluated a described canine HMGA1 exon 6 SNP in 55 Dachshunds. CONCLUSION: The performed characterisations will make comparative analyses of aberrations affecting the human and canine gene and proteins possible, thereby providing a basis for revealing mechanisms involved in HMGA1 related pathogenesis in both species.

9-year clinical follow-up of patients with ST-segment elevation myocardial infarction with Genous or TAXUS Liberté stents.

OBJECTIVES: This matched-cohort retrospective study investigated the long-term (9-year) safety and efficacy outcomes of patients with ST-segment elevation myocardial infarction (STEMI) and primary percutaneous coronary intervention (pPCI) with Genous (n = 102) versus TAXUS Liberté (n = 101) stents in 2006-2008. BACKGROUND: In the era of off-label use of drug-eluting stents for pPCI in patients with STEMI, the use of first-generation Genous stents (endothelial progenitor cell capture stents that have a passive coating and accelerate re-endothelialization) was proposed. METHODS: The primary endpoint was 9-year major adverse cardiac and cerebrovascular events (MACCE), including all-cause death, re-infarction, target vessel revascularization (TVR), and stroke. The secondary endpoints were the separate primary endpoint events at pre-defined time-points (in-hospital, 6 months, and yearly) and stent thrombosis. Time-dependent 9-year composite MACCE, all-cause death, and TVR were compared using Kaplan-Meier estimates and multivariate Cox regression models. RESULTS: Propensity score analysis confirmed the comparability of the groups. Patients in the Genous and TAXUS groups had 7 and 1 acute definitive stent thrombosis events, respectively (p<0.001). There was a trend towards higher in-hospital MACCE in the Genous group (10.8%) versus the TAXUS group (4.0%). Kaplan-Meier analysis showed that 9-year MACCE was significantly worse in the Genous than in the TAXUS group. The in-hospital, 6-month, 1-year, and 9-year mortality rates were 7.8%, 8.8%, 9.8%, and 23.5% in the Genous group and 2.0%, 3.0%, 4.0%, and 16.8% in the TAXUS group. CONCLUSIONS: Higher peri-procedural, in-hospital, and short-term mortality led to worse outcomes for first-generation Genous stents versus TAXUS Liberté stents for pPCI in STEMI. TAXUS Liberté stents had more favorable 9-year clinical outcomes.

Diagnostic Performance of Fully Automated Pixel-Wise Quantitative Myocardial Perfusion Imaging by Cardiovascular Magnetic Resonance.

OBJECTIVES: The authors developed a fully automated framework to quantify myocardial blood flow (MBF) from contrast-enhanced cardiac magnetic resonance (CMR) perfusion imaging and evaluated its diagnostic performance in patients. BACKGROUND: Fully quantitative CMR perfusion pixel maps were previously validated with microsphere MBF measurements and showed potential in clinical applications, but the methods required laborious manual processes and were excessively time-consuming. METHODS: CMR perfusion imaging was performed on 80 patients with known or suspected coronary artery disease (CAD) and 17 healthy volunteers. Significant CAD was defined by quantitative coronary angiography (QCA) as ≥70% stenosis. Nonsignificant CAD was defined by: 1) QCA as <70% stenosis; or 2) coronary computed tomography angiography as <30% stenosis and a calcium score of 0 in all vessels. Automatically generated MBF maps were compared with manual quantification on healthy volunteers. Diagnostic performance of the automated MBF pixel maps was analyzed on patients using absolute MBF, myocardial perfusion reserve (MPR), and relative measurements of MBF and MPR. RESULTS: The correlation between automated and manual quantification was excellent (r = 0.96). Stress MBF and MPR in the ischemic zone were lower than those in the remote myocardium in patients with significant CAD (both p < 0.001). Stress MBF and MPR in the remote zone of the patients were lower than those in the normal volunteers (both p < 0.001). All quantitative metrics had good area under the curve (0.864 to 0.926), sensitivity (82.9% to 91.4%), and specificity (75.6% to 91.1%) on per-patient analysis. On a per-vessel analysis of the quantitative metrics, area under the curve (0.837 to 0.864), sensitivity (75.0% to 82.7%), and specificity (71.8% to 80.9%) were good. CONCLUSIONS: Fully quantitative CMR MBF pixel maps can be generated automatically, and the results agree well with manual quantification. These methods can discriminate regional perfusion variations and have high diagnostic performance for detecting significant CAD. (Technical Development of Cardiovascular Magnetic Resonance Imaging; NCT00027170).

HMGA2 expression in a canine model of prostate cancer.

Prostate cancer is the most prevalent cancer in western countries, being the third leading cause of male cancer death. To check its possible significance as a prognostic marker, allowing a better prognosis of the tumor, we analyzed the high-mobility group protein-A2 gene (HMGA2) expression level because HMGA2 overexpression has been shown to correlate with the malignant potential of various neoplasias. Aside from man, the dog is the only mammalian species that shows spontaneously occurring prostate carcinoma with striking similarities to prostate cancer growth and progression in man, making it an adequate animal model for this neoplasia. We used real-time quantitative reverse-transcription polymerase chain reaction for HMGA2 expression analyses in a subset of canine prostate tissue samples. Our investigations reveal that HMGA2 expression levels in all carcinomas were higher than those of any of the nonmalignant tissues. Thus, canine prostate cancer represents a spontaneously occurring model to test therapeutic effects resulting from reduced expression of HMGA2.

Presence of ´isolated´ tricuspid regurgitation should prompt the suspicion of heart failure with preserved ejection fraction.

BACKGROUND: Diastolic dysfunction of the left ventricle is common but frequently under-diagnosed. Particularly in advanced stages affected patients may present with significant functional tricuspid regurgitation (TR) as the most prominent sign on echocardiography. The underlying left ventricular pathology may eventually be missed and symptoms of heart failure are attributed to TR, with respective therapeutic consequences. The aim of the present study was to determine prevalence and mechanisms underlying TR evolution in heart failure with preserved ejection fraction (HFpEF). METHODS AND RESULTS: Consecutive HFpEF patients were enrolled in this prospective, observational study. Confirmatory diagnostic tests including echocardiography and invasive hemodynamic assessments were performed. Of the 175 patients registered between 2010 and 2014, 51% had significant (moderate or severe) TR without structural abnormalities of the tricuspid valve. Significant hemodynamic differences between patients with and without relevant TR were encountered. These included elevated pulmonary vascular resistance (p = 0.038), reduced pulmonary arterial compliance (PAC, p = 0.005), and elevated left ventricular filling pressures (p = 0.039) in the TR group. Multivariable binary logistic regression analysis revealed diastolic pulmonary artery pressure (p = 0.029) and PAC (p = 0.048) as independent determinants of TR. Patients were followed for 18.1±14.1 months, during which 32% had a cardiac event. While TR was associated with outcome in the univariable analysis, it failed to predict event-free survival in the multivariable model. CONCLUSIONS: The presence of ´isolated´ functional TR should prompt the suspicion of HFpEF. Our data show that significant TR is a marker of advanced HFpEF but neither an isolated entity nor independently associated with event-free survival.

Cloning and characterization of the canine receptor for advanced glycation end products.

Metastasis is one of the major problems when dealing with malignant neoplasias. Accordingly, the finding of molecular targets, which can be addressed to reduce tumour metastasising, will have significant impact on the development of new therapeutic approaches. Recently, the receptor for advanced glycation end products (RAGE)-high mobility group B1 (HMGB1) protein complex has been shown to have significant influence on invasiveness, growth and motility of tumour cells, which are essential characteristics required for metastatic behaviour. A set of in vitro and in vivo approaches showed that blocking of this complex resulted in drastic suppression of tumour cell growth. Due to the similarities of human and canine cancer the dog has joined the common rodent animal model for therapeutic and preclinical studies. However, complete characterisation of the protein complex is a precondition to a therapeutic approach based on the blocking of the RAGE-HMGB1 complex to spontaneously occurring tumours in dogs. We recently characterised the canine HMGB1 gene and protein completely. Here we present the complete characterisation of the canine RAGE gene including its 1384 bp mRNA, the 1215 bp protein coding sequence, the 2835 bp genomic structure, chromosomal localisation, gene expression pattern, and its 404 amino acid protein. Furthermore we compared the CDS of six different canine breeds and screened them for single nucleotide polymorphisms.

Polysomy 13 in a canine prostate carcinoma underlining its significance in the development of prostate cancer.

The dog is a well-accepted model for prostate cancer in man because of the striking similarities between both species with respect to the clinical course of the disease as well as to its similar histopathology. Cytogenetic investigations of human prostate cancers has revealed the frequent occurrence of trisomies 7, 8, and 17. In this report, we present a case of prostate carcinoma in a dog characterized by polysomy 13 as the sole cytogenetic abnormality. Along with the known homology between canine chromosome 13 and human chromosome 8 these findings suggest that a homologous area on both chromosomes plays a crucial role in subsets of prostate cancer in both species.

Cytogenetic investigations in four canine lymphomas.

Four cases of canine lymphoma are presented, including histological examination and cytogenetic investigation. The first case showed a derivative chromosome 13, the second case showed a clonal trisomy 8 and the third case showed a complex karyotype with a clonal trisomy 13 and additional clonal trisomies of the chromosomes 20, 30 and 37, as well as a non-clonal tetrasomy 9. Case four showed a single trisomy 2. Comparing these results with human hematopoietic malignancies, there are notable similarities between both species.

The canine HMGA1.

Due to the emerging advantages of numerous canine diseases as a genetic model for their human orthologs, the dog could join the mouse as the species of choice to unravel genetic mechanisms, e.g. of cancer predisposition, development and progression. However, precondition for such studies is the characterisation of the corresponding canine genes. Human and murine HMGA1 non-histone proteins participate in a wide variety of cellular processes including regulation of inducible gene transcription, integration of retroviruses into chromosomes, and the induction of neoplastic transformation and promotion of metastatic progression of cancer cells. Chromosomal aberrations affecting the human HMGA1 gene at 6p21 were described in several tumours like pulmonary chondroid hamartomas, uterine leiomyomas, follicular thyroid adenomas and others. Over-expression of the proteins of HMGA1 is characteristic for various malignant tumours suggesting a relation between high titer of the protein and the neoplastic phenotype. In this study, we characterised the molecular structure of the canine HMGA1 cDNA, its splice variants and predicted proteins HMGA1a and HMGA1b. Furthermore, we compared the coding sequence(s) (CDS) of both splice variants for 12 different breeds, screened them for single nucleotide polymorphisms (SNPs) and characterised a basic expression pattern.

Absence of ras-gene hot-spot mutations in canine fibrosarcomas and melanomas.

Point mutations within ras proto-oncogenes, particularly within the mutational hot-spot codons 12, 13 and 61, are frequently detected in human malignancies and in different types of experimentally-induced tumours in animals. So far little is known about ras mutations in naturally occurring canine fibrosarcomas or K-ras mutations in canine melanomas. To elucidate whether ras mutations exist in these naturally occurring tumours in dogs, in the present study we screened 13 canine fibrosarcomas, 2 feline fibrosarcomas and 11 canine melanomas for point mutations, particularly within the mutational hot-spots, making this the first study to investigate a large number of canine fibrosarcomas. None of the samples showed a K- or N-ras hot spot mutation. Thus, our data strongly suggest that ras mutations at the hot-spot loci are very rare and do not play a major role in the pathogenesis of the spontaneously occurring canine tumours investigated.

Expression pattern of the HMGB1 gene in sarcomas of the dog.

BACKGROUND: The human high mobility group protein B1 (HMGB1) has attracted considerable interest among oncologists because it sensitises cancer cells to the anticancer drug cisplatin by shielding cisplatin-DNA adducts from nucleotide excision repair. MATERIALS AND METHODS: Since cisplatin is the cornerstone of adjuvant systemic therapy for osteosarcomas, in both humans and dogs, the expression pattern of the HMGB1 gene in seven canine sarcomas was investigated by Northern blot analysis and semi-quantitative RT-PCR. RESULTS: A strong intertumoural variation of HMGB1 expression was detected by Northern blot analysis and confirmed by the semi-quantitative RT-PCR established herein. CONCLUSION: The observed variations of HMGB1 expression in canine sarcomas emphasises the role of HMGB1 as a potential marker of clinical interest as its expression level may predict the clinical outcome of therapies based on cisplatin. The semi-quantitative RT-PCR established allows a quick and convenient determination of the HMGB1 expression level as necessary for clinical applications.

Language aptitude for pronunciation in advanced second language (L2) learners: behavioural predictors and neural substrates.

Individual differences in second language (L2) aptitude have been assumed to depend upon a variety of cognitive and personality factors. Especially, the cognitive factor phonological working memory has been conceptualised as language learning device. However, strong associations between phonological working memory and L2 aptitude have been previously found in early-stage learners only, not in advanced learners. The current study aimed at investigating the behavioural and neurobiological predictors of advanced L2 learning. Our behavioural results showed that phonetic coding ability and empathy, but not phonological working memory, predict L2 pronunciation aptitude in advanced learners. Second, functional neuroimaging revealed this behavioural trait to be correlated with hemodynamic responses of the cerebral network of speech motor control and auditory-perceptual areas. We suggest that the acquisition of L2 pronunciation aptitude is a dynamic process, requiring a variety of neural resources at different processing stages over time.