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Seaweeds emerge as promising third-generation renewable for sustainable bioproduction. In the present work, we valorized brown seaweed to produce l -lysine, the world's leading feed amino acid, using Corynebacterium glutamicum, which was streamlined by systems metabolic engineering. The mutant C. glutamicum SEA-1 served as a starting point for development because it produced small amounts of l -lysine from mannitol, a major seaweed sugar, because of the deletion of its arabitol repressor AtlR and its engineered l -lysine pathway. Starting from SEA-1, we systematically optimized the microbe to redirect excess NADH, formed on the sugar alcohol, towards NADPH, required for l -lysine synthesis. The mannitol dehydrogenase variant MtlD D75A, inspired by 3D protein homology modelling, partly generated NADPH during the oxidation of mannitol to fructose, leading to a 70% increased l -lysine yield in strain SEA-2C. Several rounds of strain engineering further increased NADPH supply and l -lysine production. The best strain, SEA-7, overexpressed the membrane-bound transhydrogenase pntAB together with codon-optimized gapN, encoding NADPH-dependent glyceraldehyde 3-phosphate dehydrogenase, and mak, encoding fructokinase. In a fed-batch process, SEA-7 produced 76 g L−1 l -lysine from mannitol at a yield of 0.26 mol mol−1 and a maximum productivity of 2.1 g L−1 h−1. Finally, SEA-7 was integrated into seaweed valorization cascades. Aqua-cultured Laminaria digitata, a major seaweed for commercial alginate, was extracted and hydrolyzed enzymatically, followed by recovery and clean-up of pure alginate gum. The residual sugar-based mixture was converted to l -lysine at a yield of 0.27 C-mol C-mol−1 using SEA-7. Second, stems of the wild-harvested seaweed Durvillaea antarctica, obtained as waste during commercial processing of the blades for human consumption, were extracted using acid treatment. Fermentation of the hydrolysate using SEA-7 provided l -lysine at a yield of 0.40 C-mol C-mol−1. Our findings enable improvement of the efficiency of seaweed biorefineries using tailor-made C. glutamicum strains.

Background Popliteal artery aneurysms (PAAs) are the most common peripheral aneurysms. Although rare and often asymptomatic, there is a significant risk of thrombosis, embolism, and limb loss. The aim of this study was to evaluate the eligibility for endovascular repair of patients treated for symptomatic and asymptomatic PAAs in accordance with the instructions for use (IFU). Methods All patients treated for PAA with open surgical repair between the years 2010 and 2017 were analyzed if suitable for endovascular treatment. Preoperative imaging was reviewed for applicability with an interventional radiologist and 2 vascular surgeons. Evaluation was performed in accordance with the following criteria adopted from the IFU of the Gore ® Viabahn stent graft: at least a single-vessel tibial runoff, proximal and distal landing zone more than 2 cm, no large difference in vessel diameter proximal and distal to the aneurysm, no overstenting of significant collaterals necessary, and no inadequate kinking of the artery. The patients were classified in 3 categories: the patient was eligible, endovascular treatment was feasible, and endovascular treatment was not appropriate. Results 51 patients with 61 symptomatic and asymptomatic PAAs were identified. Forty-five cases were asymptomatic, 11 cases showed clinical symptoms such as claudication, and in 5 cases, the patients presented with acute ischemia. Twenty-four patients were eligible for endovascular intervention, 14 cases were feasible, and in 23 cases, it was not appropriate in accordance with the IFU. Conclusions In this study, more than one-third of the patients with PAA were not eligible for endovascular treatment in accordance with the IFU and another 23 % showed substantial reasons against endovascular treatment. These data suggest that endovascular repair remains a treatment option for selected patients only. Cross-sectional imaging is mandatory for procedure selection.

Purpose: Non-invasive cerebral oxygen saturation (ScO2) monitoring is an established tool in the intraoperative phase of pediatric congenital cardiac surgery (CCS). This study investigated the association between ScO2 and postoperative outcome by investigating both baseline ScO2 values and intraoperative desaturations from baseline. Methods: All CCS procedures performed in the period 2010-2017 in our institution in which ScO2 was monitored were included in this historical cohort study. Baseline ScO2 was determined after tracheal intubation, before surgical incision. Subgroups were based on cardiac pathology and degree of intracardiac shunting. Poor outcome was defined based on length of stay (LOS) in the intensive care unit (ICU)/hospital, duration of mechanical ventilation (MV), and 30-day mortality. Intraoperatively, ScO2 total time below baseline (TBBL) and ScO2 time-weighted average (TWA) were calculated. Results: Data from 565 patients were analyzed. Baseline ScO2 was significantly associated with LOS in ICU (odds ratio [OR] per percentage decrease in baseline ScO2, 0.95; 95% confidence interval [CI], 0.93 to 0.97; P < 0.001), with LOS in hospital (OR, 0.93; 95% CI, 0.91 to 0.96; P < 0.001), with MV duration (OR, 0.92; 95% CI, 0.90 to 0.95; P < 0.001) and with 30-day mortality (OR, 0.94; 95% CI, 0.91 to 0.98; P = 0.007). Cerebral oxygen saturation TWA had no associations, while ScO2 TBBL had only a small association with LOS in ICU (OR, 1.02; 95% CI, 1.01 to 1.03; P < 0.001), MV duration (OR,1.02; 95% CI, 1.01 to 1.03; P = 0.002), and LOS in hospital (OR, 1.02; 95% CI, 1.01 to 1.04; P < 0.001). Conclusion: In pediatric patients undergoing cardiac surgery, low baseline ScO2 values measured after tracheal intubation were associated with several adverse postoperative outcomes. In contrast, the severity of actual intraoperative cerebral desaturation was not associated with postoperative outcomes. Baseline ScO2 measured after tracheal intubation may help identify patients at increased perioperative risk.

Focus groups are used in qualitative research and increasingly so in the health and nursing sciences. There has been no previous research on how focus groups are used and reported in this context. A scoping review was conducted to address this question.The databases MEDLINE via PubMed, CINAHL, and SSCI were searched for nursing and health science publications (2009-2019) that reported focus groups as a method. Due to the high number of hits, a one percent random sample was drawn per database. Two individuals checked the inclusion and exclusion criteria. Data extraction was performed using a literature-based matrix developed and discussed with experts. Results were content-analysed and quantified.The random sample was n=408 publications, of which n=319 were included after reviewing the inclusion and exclusion criteria. The use of semi-structured interview guides was reported most frequently (43.9 %) (more often referred to as focus group interviews in the publications); open discussions (11 %) and discussions without any guiding questions (6.3 %) were reported less frequently (more often referred to as focus group discussions in the publications). In none of the publications was the aspect of group interaction included into the analysis. Although the reporting is based on international standards, some specific methodological aspects were often inadequately reported or not reported at all: in 92 % of the publications there is no information about the interaction of the participants, and in 72 % the role of the moderating person was not described in detail.Semi-structured forms of focus groups predominate but open forms with only one introductory question are also used. It would have been expected that the interaction among the participants and group dynamic processes would have been considered in the more open approaches. Method-specific reporting items for focus groups have yet to be developed. This could contribute to an improvement of the reporting and critical reflection of, in particular, method-specific aspects. There is evidence that different nomenclature is used in the international literature, depending on the type of focus group. Researchers should choose the nomenclature carefully and describe the procedure precisely.The scoping review provides first insights into how focus groups are conducted and reported in health and nursing science research. The potential of the method could be more fully exploited regarding the analysis of group interaction. Future methodological work dealing with the focus group method should promote the establishment of an internationally consented nomenclature and the development of criteria for transparent reporting for different types of focus groups.

BackgroundThe global burden of hypertension, currently estimated at 1 billion, is a leading Non-Communicable Disease (NCD) in Sub Saharan Africa. In Tanzania, the reported prevalence of hypertension is 25%. Inherent limitations of the healthcare system to control hypertension include inadequate provider knowledge, system capacity, medication access, and patient awareness, all of which hinder effective screening and disease management. To assess the quality of hypertension screening and patient counseling, we conducted a study in an ambulatory setting in Tanzania.MethodsObservations of patient screening were conducted on 69 adult patients during routine outpatient care and screening camps. In addition, 33 healthcare providers participated in a pre-post knowledge assessment after observing instructional training videos.ResultsPatient observations indicated that blood pressure (BP) measurement was explained to 65% of patients, and 77% of the measurements were made with mercury sphygmomanometers. For several aspects of BP measurement, nurses performed better than doctors: patient's arm supported on a flat surface (doctors, 58% vs nurses 67%, pConclusionEnhancing knowledge and performance competencies of health providers at the primary care level is a critical prerequisite for effective hypertension management in low resource settings.