Doppler flow morphology characteristics of epiaortic arteries in aortic valve pathologies: a retrospective study on a cohort of patients with ischemic stroke.

BACKGROUND AND AIMS: Neurovascular ultrasound (nvUS) of the epiaortic arteries is an integral part of the etiologic workup in patients with ischemic stroke. Aortic valve disease shares similar vascular risk profiles and therefore not only presents a common comorbidity, but also an etiologic entity. The aim of this study is to investigate the predictive value of specific Doppler curve flow characteristics in epiaortic arteries and the presence of aortic valve disease. METHODS: Retrospective, single-center analysis of ischemic stroke patients, both receiving full nvUS of the extracranial common- (CCA), internal- (ICA) and external carotid artery (ECA) and echocardiography (TTE/TEE) during their inpatient stay. A rater blinded for the TTE/TEE results investigated Doppler flow curves for the following characteristics: 'pulsus tardus et parvus' for aortic valve stenosis (AS) and 'bisferious pulse', 'diastolic reversal', 'zero diastole' and 'no dicrotic notch' for aortic valve regurgitation (AR). Predictive value of these Doppler flow characteristics was investigated using multivariate logistic regression models. RESULTS: Of 1320 patients with complete examination of Doppler flow curves and TTE/TEE, 75 (5.7%) showed an AS and 482 (36.5%) showed an AR. Sixty-one (4.6%) patients at least showed a moderate-to-severe AS and 100 (7.6%) at least showed a moderate-to-severe AR. After adjustment for age, coronary artery disease, arterial hypertension, diabetes mellitus, smoking, peripheral arterial disease, renal failure and atrial fibrillation, the following flow pattern predicted aortic valve disease: 'pulsus tardus et parvus' in the CCA and ICA was highly predictive for a moderate-to-severe AS (OR 1158.5, 95% CI 364.2-3684.8, p < 0.001). 'No dicrotic notch' (OR 102.1, 95% CI 12.4-839.4, p < 0.001), a 'bisferious pulse' (OR 10.8, 95% CI 3.2-33.9, p < 0.001) and a 'diastolic reversal' (OR 15.4, 95% CI 3.2-74.6, p < 0.001) in the CCA and ICA predicted a moderate-to-severe AR. The inclusion of Doppler flow characteristics of the ECA did not increase predictive value. CONCLUSIONS: Well defined, qualitative Doppler flow characteristics detectable in the CCA and ICA are highly predictive for aortic valve disease. The consideration of these flow characteristics can be useful to streamline diagnostic and therapeutic measures, especially in the outpatient setting.

Thirty-day outcomes of the Cardioband tricuspid system for patients with symptomatic functional tricuspid regurgitation: The TriBAND study.

BACKGROUND: Severe tricuspid regurgitation (TR) has limited treatment options and is associated with high morbidity and mortality. AIMS: We evaluated the safety and effectiveness of the Cardioband tricuspid valve reconstruction system from the ongoing European single-arm, multicentre, prospective TriBAND post-market clinical follow-up study. METHODS: Eligible patients had chronic symptomatic functional TR despite diuretic therapy and were deemed candidates for transcatheter tricuspid repair by the local Heart Team. RESULTS: Sixty-one patients had ≥severe functional TR. At baseline, 85% of patients were in NYHA Class III-IV, 94% had ≥severe TR (core laboratory-assessed) with 6.8% EuroSCORE II and 53% LVEF. Device success was 96.7%. At discharge, 59% (p<0.001) of patients achieved ≤moderate TR and 78% had at least one grade TR reduction. At 30 days, all-cause mortality and composite MAE rates were 1.6% and 19.7%, respectively; septolateral annular diameter was reduced by 20%, where 69% of patients achieved ≤moderate TR and 85% of patients had at least one grade TR reduction (all p<0.001). Mid-RVEDD, RA volume, and IVC diameter decreased by 10% (p=0.005), 21% (p<0.001), and 11% (p=0.022), respectively; 74% were in NYHA Class I-II (p<0.001) with improvements in overall KCCQ score by 17 points (p<0.001). CONCLUSIONS: In the TriBAND study, the Cardioband tricuspid system demonstrated favourable outcomes at discharge and 30 days in a challenging patient population with symptomatic ≥severe functional TR. Results showed significant reductions in annular diameter and TR severity, accompanied by early evidence of right heart remodelling and improvements in functional status and quality of life.

Comparing the diagnostic value of Echocardiography In Stroke (CEIS) - results of a prospective observatory cohort study.

BACKGROUND: Echocardiography is one of the main diagnostic tools for the diagnostic workup of stroke and is already well integrated into the clinical workup. However, the value of transthoracic vs. transesophageal echocardiography (TTE/TEE) in stroke patients is still a matter of debate. Aim of this study was to characterize relevant findings of TTE and TEE in the management of stroke patients and to correlate them with subsequent clinical decisions and therapies. METHODS: We evaluated n = 107 patients admitted with an ischemic stroke or transient ischemic attack to our stroke unit of our university medical center. They underwent TTE and TEE examination by different blinded investigators. RESULTS: Major cardiac risk factors were found in 8 of 98 (8.2%) patients and minor cardiac risk factors for stroke were found in 108 cases. We found a change in therapeutic regime after TTE or TEE in 22 (22.5%) cases, in 5 (5%) cases TEE leads to the change of therapeutic regime, in 4 (4%) TTE and in 13 cases (13.3%) TTE and TEE lead to the same change in therapeutic regime. The major therapy change was the indication to close a patent foramen ovale (PFO) in 9 (9.2%) patients with TTE and in 10 (10.2%) patients with TEE (p = 1.000). CONCLUSION: Major finding with clinical impact on therapy change is the detection of PFO. But for the detection of PFO, TTE is non inferior to TEE, implicating that TTE serves as a good screening tool for detection of PFO, especially in young age patients. TRIAL REGISTRATION: The trial was registered and approved prior to inclusion by our local ethics committee (1/3/17).

Comparative study of human-induced pluripotent stem cells derived from bone marrow cells, hair keratinocytes, and skin fibroblasts.

AIMS: Induced pluripotent stem cells (iPSCs) provide a unique opportunity for the generation of patient-specific cells for use in disease modelling, drug screening, and regenerative medicine. The aim of this study was to compare human-induced pluripotent stem cells (hiPSCs) derived from different somatic cell sources regarding their generation efficiency and cardiac differentiation potential, and functionalities of cardiomyocytes. METHODS AND RESULTS: We generated hiPSCs from hair keratinocytes, bone marrow mesenchymal stem cells (MSCs), and skin fibroblasts by using two different virus systems. We show that MSCs and fibroblasts are more easily reprogrammed than keratinocytes. This corresponds to higher methylation levels of minimal promoter regions of the OCT4 and NANOG genes in keratinocytes than in MSCs and fibroblasts. The success rate and reprogramming efficiency was significantly higher by using the STEMCCA system than the OSNL system. All analysed hiPSCs are pluripotent and show phenotypical characteristics similar to human embryonic stem cells. We studied the cardiac differentiation efficiency of generated hiPSC lines (n = 24) and found that MSC-derived hiPSCs exhibited a significantly higher efficiency to spontaneously differentiate into beating cardiomyocytes when compared with keratinocyte-, and fibroblast-derived hiPSCs. There was no significant difference in the functionalities of the cardiomyocytes derived from hiPSCs with different origins, showing the presence of pacemaker-, atrial-, ventricular- and Purkinje-like cardiomyocytes, and exhibiting rhythmic Ca2+ transients and Ca2+ sparks in hiPSC-derived cardiomyocytes. Furthermore, spontaneously and synchronously beating and force-developing engineered heart tissues were generated. CONCLUSIONS: Human-induced pluripotent stem cells can be reprogrammed from all three somatic cell types, but with different efficiency. All analysed iPSCs can differentiate into cardiomyocytes, and the functionalities of cardiomyocytes derived from different cell origins are similar. However, MSC-derived hiPSCs revealed a higher cardiac differentiation efficiency than keratinocyte- and fibroblast-derived hiPSCs.

Essential role of the p110beta subunit of phosphoinositide 3-OH kinase in male fertility.

Phosphoinositide 3-kinases (PI3K) are key molecular players in male fertility. However, the specific roles of different p110 PI3K catalytic subunits within the spermatogenic lineage have not been characterized so far. Herein, we report that male mice expressing a catalytically inactive p110beta develop testicular hypotrophy and impaired spermatogenesis, leading to a phenotype of oligo-azoospermia and defective fertility. The examination of testes from p110beta-defective tubules demonstrates a widespread loss in spermatogenic cells, due to defective proliferation and survival of pre- and postmeiotic cells. In particular, p110beta is crucially needed in c-Kit-mediated spermatogonial expansion, as c-Kit-positive cells are lost in the adult testis and activation of Akt by SCF is blocked by a p110beta inhibitor. These data establish that activation of the p110beta PI3K isoform by c-Kit is required during spermatogenesis, thus opening the way to new treatments for c-Kit positive testicular cancers.

Isolation and cultivation of stem cells from adult mouse testes.

The successful isolation and cultivation of spermatogonial stem cells (SSCs) as well as induction of SSCs into pluripotent stem cells will allow us to study their biological characteristics and their applications in therapeutic approaches. Here we provide step-by-step procedures on the basis of previous work in our laboratory for: the isolation of testicular cells from adolescent mice by a modified enzymatic procedure; the enrichment of undifferentiated spermatogonia by laminin selection or genetic selection using Stra8-EGFP (enhanced green fluorescent protein) transgenic mice; the cultivation and conversion of undifferentiated spermatogonia into embryonic stem-like cells, so-called multipotent adult germline stem cells (maGSCs); and characterization of these cells. Normally, it will take about 16 weeks to obtain stable maGSC lines starting from the isolation of testicular cells.

Pluripotency of spermatogonial stem cells from adult mouse testis.

Embryonic germ cells as well as germline stem cells from neonatal mouse testis are pluripotent and have differentiation potential similar to embryonic stem cells, suggesting that the germline lineage may retain the ability to generate pluripotent cells. However, until now there has been no evidence for the pluripotency and plasticity of adult spermatogonial stem cells (SSCs), which are responsible for maintaining spermatogenesis throughout life in the male. Here we show the isolation of SSCs from adult mouse testis using genetic selection, with a success rate of 27%. These isolated SSCs respond to culture conditions and acquire embryonic stem cell properties. We name these cells multipotent adult germline stem cells (maGSCs). They are able to spontaneously differentiate into derivatives of the three embryonic germ layers in vitro and generate teratomas in immunodeficient mice. When injected into an early blastocyst, SSCs contribute to the development of various organs and show germline transmission. Thus, the capacity to form multipotent cells persists in adult mouse testis. Establishment of human maGSCs from testicular biopsies may allow individual cell-based therapy without the ethical and immunological problems associated with human embryonic stem cells. Furthermore, these cells may provide new opportunities to study genetic diseases in various cell lineages.