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Abstract Background In recent years, lytic polysaccharide monooxygenases (LPMOs) that oxidatively cleave cellulose have gained increasing attention in cellulose fiber modification. LPMOs are relatively small copper-dependent redox enzymes that occur as single domain proteins but may also contain an appended carbohydrate-binding module (CBM). Previous studies have indicated that the CBM “immobilizes” the LPMO on the substrate and thus leads to more localized oxidation of the fiber surface. Still, our understanding of how LPMOs and their CBMs modify cellulose fibers remains limited. Results Here, we studied the impact of the CBM on the fiber-modifying properties of NcAA9C, a two-domain family AA9 LPMO from Neurospora crassa, using both biochemical methods as well as newly developed multistep fiber dissolution methods that allow mapping LPMO action across the fiber, from the fiber surface to the fiber core. The presence of the CBM in NcAA9C improved binding towards amorphous (PASC), natural (Cell I), and alkali-treated (Cell II) cellulose, and the CBM was essential for significant binding of the non-reduced LPMO to Cell I and Cell II. Substrate binding of the catalytic domain was promoted by reduction, allowing the truncated CBM-free NcAA9C to degrade Cell I and Cell II, albeit less efficiently and with more autocatalytic enzyme degradation compared to the full-length enzyme. The sequential dissolution analyses showed that cuts by the CBM-free enzyme are more evenly spread through the fiber compared to the CBM-containing full-length enzyme and showed that the truncated enzyme can penetrate deeper into the fiber, thus giving relatively more oxidation and cleavage in the fiber core. Conclusions These results demonstrate the capability of LPMOs to modify cellulose fibers from surface to core and reveal how variation in enzyme modularity can be used to generate varying cellulose-based materials. While the implications of these findings for LPMO-based cellulose fiber engineering remain to be explored, it is clear that the presence of a CBM is an important determinant of the three-dimensional distribution of oxidation sites in the fiber.

Abstract Background Microbial expansins (EXLXs) are non-lytic proteins homologous to plant expansins involved in plant cell wall formation. Due to their non-lytic cell wall loosening properties and potential to disaggregate cellulosic structures, there is considerable interest in exploring the ability of microbial expansins (EXLX) to assist the processing of cellulosic biomass for broader biotechnological applications. Herein, EXLXs with different modular structure and from diverse phylogenetic origin were compared in terms of ability to bind cellulosic, xylosic, and chitinous substrates, to structurally modify cellulosic fibrils, and to boost enzymatic deconstruction of hardwood pulp. Results Five heterogeneously produced EXLXs (Clavibacter michiganensis; CmiEXLX2, Dickeya aquatica; DaqEXLX1, Xanthomonas sacchari; XsaEXLX1, Nothophytophthora sp.; NspEXLX1 and Phytophthora cactorum; PcaEXLX1) were shown to bind xylan and hardwood pulp at pH 5.5 and CmiEXLX2 (harboring a family-2 carbohydrate-binding module) also bound well to crystalline cellulose. Small-angle X-ray scattering revealed a 20–25% increase in interfibrillar distance between neighboring cellulose microfibrils following treatment with CmiEXLX2, DaqEXLX1, or NspEXLX1. Correspondingly, combining xylanase with CmiEXLX2 and DaqEXLX1 increased product yield from hardwood pulp by ~ 25%, while supplementing the TrAA9A LPMO from Trichoderma reesei with CmiEXLX2, DaqEXLX1, and NspEXLX1 increased total product yield by over 35%. Conclusion This direct comparison of diverse EXLXs revealed consistent impacts on interfibrillar spacing of cellulose microfibers and performance of carbohydrate-active enzymes predicted to act on fiber surfaces. These findings uncover new possibilities to employ EXLXs in the creation of value-added materials from cellulosic biomass.

Background: Catheter ablation is a well-established treatment to prevent atrial fibrillation (AF) and atrial flutter (AFL) recurrences and to relieve symptoms, whereas pacemaker implantation and atrioventricular node (AVN) ablation is used for rate control when medical therapy fails. Aims: We investigated temporal trends and patient characteristics in catheter ablation procedures for AF, AFL and AVN in Finland between 2012–2018. Methods: Finnish AntiCoagulation in Atrial Fibrillation (FinACAF) is a registry-based study including all patients with AF or AFL in Finland between 2012–2018. Results: The number of patients with AF or AFL diagnosis in Finland increased from 185 057 to 243 802 between 2012–2018 and a total of 8954 first-time catheter ablation procedures were performed. Of them, 4909 (54.8 %) were AF ablations, 2731 (30.5 %) AFL ablations and 1314 (14.7 %) AVN ablations. The procedural numbers increased from 457/year to 934/year for AF, from 223/year to 553/year for AFL and from 114/year to 238/year for AVN. Altogether, 0.65% of all patients with diagnosed AF or AFL underwent AF, AFL or AVN ablation in 2018. The mean age of the patients increased in all ablation groups. Patients undergoing AF and AFL ablations were predominantly men (69.7 % and 74.6 % respectively) whereas patients undergoing AVN ablation were more often women (56.9%). Conclusions: The use of catheter ablation more than doubled during 2012–2018 and the increase was particularly seen in the elderly patients. Nevertheless, only a minority of AF and AFL patients were treated with catheter ablations.

This study explored student teachers' experiences of study engagement and burnout by utilising profile analysis. Interrelations between the student teachers' profiles and perceptions of their learning environment were also explored. To complement the statistical analysis, the student teachers' social support experiences during teaching practice were explored based on interview data. Two study engagement-burnout profiles were detected among student teachers. The student teachers exhibiting the "engaged in studies with a low risk of burnout profile" had significantly more positive perceptions of their learning environments compared with the group classified under the "reduced study engagement with an increased risk of burnout profile." Further investigation showed that student teachers most frequently reported informational support received from their teaching practice supervisors. The groups representing the two profiles showed both similar and different characteristics in the types and sources of social support. The study contributes to the understanding of student teachers' study engagement in relation to the learning environment of teacher education. It provides practical implications for teacher educators to improve the learning environments of differently engaged student teachers, particularly during teaching practice, a central arena for student teacher learning.

Abstract The ATP-binding cassette transporter (ABCC1) is associated with poor survival and chemotherapy drug resistance in high grade serous ovarian cancer (HGSOC). The mechanisms driving ABCC1 expression are poorly understood. Alternative polyadenylation (APA) can give rise to ABCC1 mRNAs which differ only in the length of their 3′untranslated regions (3′UTRs) in a process known as 3′UTR-APA. Like other ABC transporters, shortening of the 3′UTR of ABCC1 through 3′UTR-APA would eliminate microRNA binding sites found within the longer 3′UTRs, hence eliminating miRNA regulation and altering gene expression. We found that the HGSOC cell lines Caov-3 and Ovcar-3 express higher levels of ABCC1 protein than normal cells. APA of ABCC1 occurs in all three cell lines resulting in mRNAs with both short and long 3′UTRs. In Ovcar-3, mRNAs with shorter 3′UTRs dominate resulting in a six-fold increase in protein expression. We were able to show that miR-185-5p and miR-326 both target the ABCC1 3′UTR. Hence, 3′UTR-APA should be considered as an important regulator of ABCC1 expression in HGSOC. Both HGSOC cell lines are cisplatin resistant, and we used erastin to induce ferroptosis, an alternative form of cell death. We showed that we could induce ferroptosis and sensitize the cisplatin resistant cells to cisplatin by using erastin. Knocking down ABCC1 resulted in decreased cell viability, but did not contribute to erastin induced ferroptosis.

Abstract Background Enzyme-aided valorization of lignocellulose represents a green and sustainable alternative to the traditional chemical industry. The recently discovered lytic polysaccharide monooxygenases (LPMOs) are important components of the state-of-the art enzyme cocktails for cellulose conversion. Yet, these monocopper enzymes are poorly characterized in terms of their kinetics, as exemplified by the growing evidence for that H2O2 may be a more efficient co-substrate for LPMOs than O2. LPMOs need external electron donors and one key question of relevance for bioprocess development is whether the required reducing power may be provided by the lignocellulosic substrate. Results Here, we show that the liquid fraction (LF) resulting from hydrothermal pretreatment of wheat straw supports LPMO activity on both chitin and cellulose. The initial, transient activity burst of the LPMO reaction was caused by the H2O2 present in the LF before addition of LPMO, while the steady-state rate of LPMO reaction was limited by the LPMO-independent production of H2O2 in the LF. H2O2 is an intermediate of LF oxidation as evidenced by a slow H2O2 accumulation in LF, despite high H2O2 production rates. This H2O2 scavenging ability of LF is important since high concentrations of H2O2 may lead to irreversible inactivation of LPMOs. Conclusions Our results support the growing understanding that fine-tuned control over the rates of H2O2 production and consumption in different, enzymatic and non-enzymatic reactions is essential for harnessing the full catalytic potential of LPMOs in lignocellulose valorization.

BackgroundCatecholaminergic polymorphic ventricular tachycardia (CPVT) is a severe inherited arrhythmic disease associated with a risk of syncope and sudden cardiac death (SCD).AimsWe aimed at identifying RYR2 P2328S founder mutation carriers and describing the clinical course associated with the mutation.MethodsThe study population was drawn from the Finnish Inherited Cardiac Disorder Research Registry, and from the present genealogical study. Kaplan-Meier graphs, log-rank test and Cox regression model were used to evaluate the clinical course.ResultsGenealogical study revealed a common ancestor couple living in the late 17th century. A total of 1837 living descendants were tested for RYR2 P2328S mutation unveiling 62 mutation carriers aged mean 39±23 years old. No arrhythmic deaths were documented among genotyped subjects, but 11 SCDs were detected in non-genotyped family members since 1970. Three genotyped patients (5%) suffered an aborted cardiac arrest (ACA), and 15 (25%) had a syncope triggered by exercise or stress. Rate of cardiac events was higher among patients who in exercise stress test showed a maximum rate of premature ventricular contractions >30/min (68% vs 17%, pConclusionsPreviously undiagnosed CPVT patients may be identified by well-conducted genealogical studies. The RYR2 P2328S mutation causes a potentially severe phenotype, but its expression is variable, thus calling for additional studies on modifying factors.

Abstract Background Long QT syndrome (LQTS) is an inherited cardiac disorder predisposing to sudden cardiac death (SCD). We studied factors affecting the clinical course of genetically confirmed patients, in particular those not receiving β-blocker treatment. In addition, an attempt was made to associate risk of events to specific types of KCNQ1 and KCNH2 mutations. Methods A follow-up study covering a mean of 18.6 ± 6.1 years was conducted in 867 genetically confirmed LQT1 and LQT2 patients and 654 non-carrier relatives aged 18–40 years. Cox regression models were used to evaluate the contribution of clinical and genetic risk factors to cardiac events. Results In mutation carriers, risk factors for cardiac events before initiation of β-blocker included LQT2 genotype (hazard ratio [HR] = 2.1, p = 0.002), female gender (HR = 3.2, p G and other KCNQ1 mutation carriers after adjusting for gender, QTc duration, and cardiac events before age 18. KCNH2 c.453delC, L552S and R176W mutations associated with lower risk (HR = 0.11–0.23, p

A significant wave height of 7 m has been measured five times by the northern Baltic Proper wave buoy in the Baltic Sea, exceeding 8 m twice (2004 and 2017). We classified these storms into two groups by duration and wave steepness. Interestingly, the two highest events exhibited opposite properties, with the 2017 event being the longest storm on record. This storm is also the first where the harshest wave conditions were modelled to occur in the western part of the Baltic Proper. The metrics quantifying the storm's duration and steepness might aid in issuing warnings for extreme wave conditions.