Influence of operative strategy for the aortic arch in DeBakey type I aortic dissection: Analysis of the German Registry for Acute Aortic Dissection Type A

ObjectivePatients treated with an extensive approach including total aortic arch replacement for acute aortic dissection type A may have a favorable long-term prognosis by treating the residual false lumen. Our goal was to analyze the operative strategy for treatment of type I DeBakey aortic dissection from the German Registry for Acute Aortic Dissection Type A (GERAADA) data.MethodsA total of 658 patients with type I DeBakey aortic dissection and entry only in the ascending aorta were identified in the GERAADA. Patients in group A underwent replacement of the ascending aorta with hemiarch replacement. Patients in group B received extensive treatment with total arch replacement or conventional or frozen elephant trunk.ResultsA total of 518 patients in group A and 140 patients in group B were treated. There was an overall 30-day mortality of 20.2% (n = 133). Group A had a slightly lower rate of mortality with 18.7% (n = 97) compared with 25.7% for group B (n = 36), but with no statistical significant difference (P = .067). The onset of new neurologic deficit (13.6% in group vs 12.5% in group B, P = .78) and new malperfusion deficit (8.4% in group A vs 10.7% in group B, P = .53) showed no statistical difference.ConclusionsOn analysis of the GERAADA data, it seems that a more aggressive approach of aortic arch treatment can be applied without higher perioperative risk even in the onset of acute aortic dissection type A. Long-term follow-up data analysis will be necessary to offer the optimal surgical strategy for different patient groups

Gene expression analysis on small numbers of invasive cells collected by chemotaxis from primary mammary tumors of the mouse

BACKGROUND: cDNA microarrays have the potential to identify the genes involved in invasion and metastasis. However, when used with whole tumor tissue, the results average the expression patterns of different cell types. We have combined chemotaxis-based cell collection of the invasive subpopulation of cells within the primary tumor with array-based gene expression analysis to identify the genes necessary for the process of carcinoma cell invasion. RESULTS: Invasive cells were collected from live primary tumors using microneedles containing chemotactic growth factors to mimic chemotactic signals thought to be present in the primary tumor. When used with mammary tumors of rats and mice, carcinoma cells and macrophages constitute the invasive cell population. Microbeads conjugated with monoclonal anti-CD11b (Mac-1α) antibodies were used to separate macrophages from carcinoma cells. We utilized PCR-based cDNA amplification from small number of cells and compared it to the quality and complexity of conventionally generated cDNA to determine if amplified cDNA could be used with fidelity for array analysis of this cell population. These techniques showed a very high level of correlation indicating that the PCR based amplification technique yields a cDNA population that resembles, with high fidelity, the original template population present in the small number of cells used to prepare the cDNA for use with the chip. CONCLUSIONS: The specific collection of invasive cells from a primary tumor and the analysis of gene expression in these cells are is now possible. By further comparing the gene expression patterns of cells collected by invasion into microneedles with that of carcinoma cells obtained from the whole primary tumor, the blood, and whole metastatic tumors, genes that contribute to the invasive process in carcinoma cells may be identified

Bow-tie signaling in c-di-GMP: Machine learning in a simple biochemical network

Bacteria of many species rely on a simple molecule, the intracellular secondary messenger c-di-GMP (Bis-(3'-5')-cyclic dimeric guanosine monophosphate), to make a vital choice: whether to stay in one place and form a biofilm, or to leave it in search of better conditions. The c-di-GMP network has a bow-tie shaped architecture that integrates many signals from the outside world—the input stimuli—into intracellular c-di-GMP levels that then regulate genes for biofilm formation or for swarming motility—the output phenotypes. How does the ‘uninformed’ process of evolution produce a network with the right input/output association and enable bacteria to make the right choice? Inspired by new data from 28 clinical isolates of Pseudomonas aeruginosa and strains evolved in laboratory experiments we propose a mathematical model where the c-di-GMP network is analogous to a machine learning classifier. The analogy immediately suggests a mechanism for learning through evolution: adaptation though incremental changes in c-di-GMP network proteins acquires knowledge from past experiences and enables bacteria to use it to direct future behaviors. Our model clarifies the elusive function of the ubiquitous c-di-GMP network, a key regulator of bacterial social traits associated with virulence. More broadly, the link between evolution and machine learning can help explain how natural selection across fluctuating environments produces networks that enable living organisms to make sophisticated decisions

Primordial origin and diversification of plasmids in Lyme disease agent bacteria

Abstract Background: With approximately one-third of their genomes consisting of linear and circular plasmids, the Lyme disease agent cluster of species has the most complex genomes among known bacteria. We report here a comparative analysis of plasmids in eleven Borreliella (also known as Borrelia burgdorferi sensu lato) species. Results: We sequenced the complete genomes of two B. afzelii, two B. garinii, and individual B. spielmanii, B. bissettiae, B. valaisiana and B. finlandensis isolates. These individual isolates carry between seven and sixteen plasmids, and together harbor 99 plasmids. We report here a comparative analysis of these plasmids, along with 70 additional Borreliella plasmids available in the public sequence databases. We identify only one new putative plasmid compatibility type (the 30th) among these 169 plasmid sequences, suggesting that all or nearly all such types have now been discovered. We find that the linear plasmids in the non-B. burgdorferi species have undergone the same kinds of apparently random, chaotic rearrangements mediated by non-homologous recombination that we previously discovered in B. burgdorferi. These rearrangements occurred independently in the different species lineages, and they, along with an expanded chromosomal phylogeny reported here, allow the identification of several whole plasmid transfer events among these species. Phylogenetic analyses of the plasmid partition genes show that a majority of the plasmid compatibility types arose early, most likely before separation of the Lyme agent Borreliella and relapsing fever Borrelia clades, and this, with occasional cross species plasmid transfers, has resulted in few if any species-specific or geographic region-specific Borreliella plasmid types. Conclusions: The primordial origin and persistent maintenance of the Borreliella plasmid types support their functional indispensability as well as evolutionary roles in facilitating genome diversity. The improved resolution of Borreliella plasmid phylogeny based on conserved partition-gene clusters will lead to better determination of gene orthology which is essential for prediction of biological function, and it will provide a basis for inferring detailed evolutionary mechanisms of Borreliella genomic variability including homologous gene and plasmid exchanges as well as nonhomologous rearrangements

Fluorous enzymatic synthesis of phosphatidylinositides

Fluorous enzymatic synthesis is used to synthesize multiple phosphatidylinositides, which are directly immobilized on a microarray to probe protein–lipid interactions

Contemporary spinal cord protection during thoracic and thoracoabdominal aortic surgery and endovascular aortic repair: a position paper of the vascular domain of the European Association for Cardio-Thoracic Surgery†

Ischaemic spinal cord injury (SCI) remains the Achilles heel of open and endovascular descending thoracic and thoracoabdominal repair. Neurological outcomes have improved coincidentially with the introduction of neuroprotective measures. However, SCI (paraplegia and paraparesis) remains the most devastating complication. The aim of this position paper is to provide physicians with broad information regarding spinal cord blood supply, to share strategies for shortening intraprocedural spinal cord ischaemia and to increase spinal cord tolerance to transitory ischaemia through detection of ischaemia and augmentation of spinal cord blood perfusion. This study is meant to support physicians caring for patients in need of any kind of thoracic or thoracoabdominal aortic repair in decision-making algorithms in order to understand, prevent or reverse ischaemic SCI. Information has been extracted from focused publications available in the PubMed database, which are cohort studies, experimental research reports, case reports, reviews, short series and meta-analyses. Individual chapters of this position paper were assigned and after delivery harmonized by Christian D. Etz, Ernst Weigang and Martin Czerny. Consequently, further writing assignments were distributed within the group and delivered in August 2014. The final version was submitted to the EJCTS for review in September 201

Valvulotomy of the great saphenous vein in ex situ non-reversed and in situ setting: a multicenter post-market study to assess the safety and efficacy of the AndraValvulotome™”

Purpose To evaluate the safety and technical success of the AndraValvulotome™ device (Andramed GmbH, Reutlingen, Germany) in patients with peripheral arterial disease (PAD) requiring bypass surgery using the great saphenous vein (GSV) as graft. Methods This was a multicenter, post-market observational study conducted in 2021 in 11 German centers. Safety and efficacy data were prospectively collected and analyzed. Primary endpoints were the absence of device-related serious adverse events until 30 ± 7 days follow-up, the clinical efficacy of valvulotomy, which was defined as pulsatile blood flow in the bypass and the number of insufficiently destroyed vein valves. Secondary endpoints were the number of valvulotomy passages, the primary patency rate of the venous bypass (determined by a color-duplex sonography showing a normal blood flow through the bypass and absence of stenosis or occlusion), and the primary technical success defined as the absence of product-specific (serious) adverse events and clinical efficacy. Results Fifty-nine patients were enrolled. The mean age of the patients was 71 years (46–91), and 74.6% were males. The vein material used for bypass grafting had a median length of 47.5 cm (range 20–70 cm) with a median diameter of 5.0 mm (range 3–6 mm) and 4.0 mm (range 2–6 mm) in the proximal and distal segments, respectively. The technical success rate was 96.6%. The primary patency rate was 89.9% at 30 days follow-up. The clinical efficacy was rated as very good in 81% of patients, fair in 17%, and poor in 2%. Between 1 and 5 (average 2.9) valvulotome passages were performed. One product-related serious adverse event was recorded (bypass vein dissection). Conclusion The AndraValvulotome™ can be considered a safe and effective device to disrupt venous valves during in situ non-reversed bypass surgeries using GSV grafts in patients with PAD