Hepatic stellate cells in zone 1 engage in capillarization rather than myofibroblast formation in murine liver fibrosis.

The combination of lineage tracing and immunohistochemistry has helped to identify subpopulations and fate of hepatic stellate cells (HSC) in murine liver. HSC are sinusoidal pericytes that act as myofibroblast precursors after liver injury. Single cell RNA sequencing approaches have recently helped to differentiate central and portal HSC. A specific Cre line to lineage trace portal HSC has not yet been described. We used three Cre lines (Lrat-Cre, PDGFRß-CreERT2 and SMMHC-CreERT2) known to label mesenchymal cells including HSC in combination with a tdTomato-expressing reporter. All three Cre lines labeled populations of HSC as well as smooth muscle cells (SMC). Using the SMMHC-CreERT2, we identified a subtype of HSC in the periportal area of the hepatic lobule (termed zone 1-HSC). We lineage traced tdTomato-expressing zone 1-HSC over 1 year, described fibrotic behavior in two fibrosis models and investigated their possible role during fibrosis. This HSC subtype resides in zone 1 under healthy conditions; however, zonation is disrupted in preclinical models of liver fibrosis (CCl4 and MASH). Zone 1-HSC do not transform into αSMA-expressing myofibroblasts. Rather, they participate in sinusoidal capillarization. We describe a novel subtype of HSC restricted to zone 1 under physiological conditions and its possible function after liver injury. In contrast to the accepted notion, this HSC subtype does not transform into αSMA-positive myofibroblasts; rather, zone 1-HSC adopt properties of capillary pericytes, thereby participating in sinusoidal capillarization.

Intra-oscillator high harmonic source reaching 100-eV photon energy.

Resonant enhancement inside an optical cavity has been a wide-spread approach to increase efficiency of nonlinear optical conversion processes while reducing the demands on the driving laser power. This concept has been particularly important for high harmonic generation XUV sources, where passive femtosecond enhancement cavities allowed significant increase in repetition rates required for applications in photoelectron spectroscopy, XUV frequency comb spectroscopy, including the recent endeavor of thorium nuclear clock development. In addition to passive cavities, it has been shown that comparable driving conditions can be achieved inside mode-locked thin-disk laser oscillators, offering a simplified single-stage alternative. This approach is less sensitive to losses thanks to the presence of gain inside the cavity and should thus allow higher conversion efficiencies through tolerating higher intensity in the gas target. Here, we show that the intra-oscillator approach can indeed surpass the much more mature technology of passive enhancement cavities in terms of XUV flux, even reaching comparable values to single-pass sources based on chirped-pulse fiber amplifier lasers. Our system operates at 17 MHz repetition rate generating photon energies between 60 eV and 100 eV. Importantly, this covers the highly attractive wavelength for the silicon industry of 13.5 nm at which our source delivers 60 nW of outcoupled average power per harmonic order.

Using an amphiphilic diblock copolymer to understand the shear-induced structural transformation of bicontinuous microemulsions.

HYPOTHESIS: Amphiphilic diblock copolymers are known to increase the surfactant's efficiency to stabilize microemulsion, leading to higher structural order and monolayer rigidity. We thus seek to evaluate whether the addition of such polymers alters the shear behavior of bicontinuous microemulsions, in particular, their shear transformation towards lamellar structures. EXPERIMENTS: We examine the initial structure and shear response of bicontinuous /n-octane//PEP5-b-PEO5 microemulsions by coupling microfluidics with small-angle neutron scattering (SANS), attaining wall shear rates in excess of . The azimuthal analysis of the obtained 2D scattering patterns allows us to follow their structural transformation by means of the degree of anisotropy. FINDINGS: The amphiphilic diblock copolymer promotes the shear-induced transformation of bicontinuous microemulsions, resulting in up to ∼ higher degrees of anisotropy than for corresponding polymer-free microemulsions. The increased shear response observed with increasing polymer content is rationalized by combining the influence of domain size and viscosity with the stability limits of the bicontinuous microemulsion in the isothermal phase diagram. As a result, a consistent description of the degree of anisotropy is obtained, enabling the prediction of the shear-induced bicontinuous-to-lamellar transformation.

Expanding the Scope of Adenoviral Vectors by Utilizing Novel Tools for Recombination and Vector Rescue.

Recombinant adenoviruses are widely used in clinical and laboratory applications. Despite the wide variety of available sero- and genotypes, only a fraction is utilized in vivo. As adenoviruses are a large group of viruses, displaying many different tropisms, immune epitopes, and replication characteristics, the merits of translating these natural benefits into vector applications are apparent. This translation, however, proves difficult, since while research has investigated the application of these viruses, there are no universally applicable rules in vector design for non-classical adenovirus types. In this paper, we describe a generalized workflow that allows vectorization, rescue, and cloning of all adenoviral species to enable the rapid development of new vector variants. We show this using human and simian adenoviruses, further modifying a selection of them to investigate their gene transfer potential and build potential vector candidates for future applications.

Combining CRISPR-Cas-mediated terminal resolution with a novel genetic workflow to achieve high-diversity adenoviral libraries.

While recombinant adenoviruses (rAds) are widely used in both laboratory and medical gene transfer, library-based applications using this vector platform are not readily available. Recently, we developed a new method, the CRISPR-Cas9 mediated in vivo terminal resolution aiding high-efficiency rescue of rAds from recombinant DNA. Here we report on a genetic workflow that allows construction of bacterial artificial chromosome-based rAd libraries reconstituted using highly efficient terminal resolution. We utilized frequent, pre-existing genomic sequences to allow the insertion of a selection marker, complementing two selected target sites into novel endonuclease recognition sites. In the second step, this selection marker is replaced with a transgene or mutation of interest via Gibson assembly. Our approach does not cause unwanted genomic off-target mutations while providing substantial flexibility for the site and nature of the genetic modification. This new genetic workflow, which we termed half site-directed fragment replacement (HFR) allows the introduction of more than 106 unique modifications into rAd encoding BACs using laboratory scale methodology. To demonstrate the power of HFR, we rescued barcoded viral vector libraries yielding a diversity of approximately 2.5 × 104 unique rAds per cm2 of transfected cell culture.

Stepwise Approach for Transvenous Lead Extraction in a Large Single Centre Cohort.

BACKGROUND: Infection, lead dysfunction and system upgrades are all reasons that transvenous lead extraction is being performed more frequently. Many centres focus on a single method for lead extraction, which can lead to either lower success rates or higher rates of major complications. We report our experience with a systematic approach from a less invasive to a more invasive strategy without the use of laser sheaths. METHODS: Consecutive extraction procedures performed over a period of seven years in our electrophysiology laboratory were included. We performed a stepwise approach with careful traction, lead locking stylets (LLD), mechanical non-powered dilator sheaths, mechanical powered sheaths and, if needed, femoral snares. RESULTS: In 463 patients (age 69.9 ± 12.3, 31.3% female) a total of 780 leads (244 ICD leads) with a mean lead dwelling time of 5.4 ± 4.9 years were identified for extraction. Success rates for simple traction, LLD, mechanical non-powered sheaths and mechanical powered sheaths were 31.5%, 42.7%, 84.1% and 92.6%, respectively. A snare was used for 40 cases (as the primary approach for 38 as the lead structure was not intact and stepwise approach was not feasible) and was successful for 36 leads (90.0% success rate). Total success rate was 93.1%, clinical success rate was 94.1%. Rate for procedural failure was 1.1%. Success for less invasive steps and overall success for extraction was associated with shorter lead dwelling time (p < 0.001). Major procedure associated complications occurred in two patients (0.4%), including one death (0.2%). A total of 36 minor procedure-associated complications occurred in 30 patients (6.5%). Pocket hematoma correlated significantly with uninterrupted dual antiplatelet therapy (p = 0.001). Pericardial effusion without need for intervention was associated with long lead dwelling time (p = 0.01) and uninterrupted acetylsalicylic acid (p < 0.05). CONCLUSION: A stepwise approach with a progressive invasive strategy is effective and safe for transvenous lead extraction.

Success and safety of deep sedation as a primary anaesthetic approach for transvenous lead extraction: a retrospective analysis.

There is a rising number in complications associated with more cardiac electrical devices implanted (CIED). Infection and lead dysfunction are reasons to perform transvenous lead extraction. An ideal anaesthetic approach has not been described yet. Most centres use general anaesthesia, but there is a lack in studies looking into deep sedation (DS) as an anaesthetic approach. We report our retrospective experience for a large number of procedures performed with deep sedation as a primary approach. Extraction procedures performed between 2011 and 2018 in our electrophysiology laboratory have been included retrospectively. We began by applying a bolus injection of piritramide followed by midazolam as primary medication and would add etomidate if necessary. For extraction of leads a stepwise approach with careful traction, locking stylets, dilator sheaths, mechanical rotating sheaths and if needed snares and baskets has been used. A total of 780 leads in 463 patients (age 69.9 ± 12.3, 31.3% female) were extracted. Deep sedation was successful in 97.8% of patients. Piritramide was used as the main analgesic medication (98.5%) and midazolam as the main sedative (94.2%). Additional etomidate was administered in 15.1% of cases. In 2.2% of patients a conversion to general anaesthesia was required as adequate level of DS was not achieved before starting the procedure. Sedation related complications occurred in 1.1% (n = 5) of patients without sequalae. Deep sedation with piritramide, midazolam and if needed additional etomidate is a safe and feasible strategy for transvenous lead extraction.