Recovery of the PHA Copolymer P(HB-co-HHx) With Non-halogenated Solvents: Influences on Molecular Weight and HHx-Content

Biodegradable and biocompatible polyhydroxyalkanoates (PHAs) are promising alternatives to conventional plastics. Based on the chain length of their monomers they are classified as short chain length (scl-) or medium chain length (mcl-) PHA polymers. The type of monomers, the composition and the molecular weight (MW) define the polymer properties. To accelerate the use of PHA as a bulk material, the downstream associated costs need to be minimized. This study focuses on the evaluation of non-halogenated solvents, especially acetone as a scl-PHA non-solvent, for the recovery of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) – P(HB-co-HHx) – with an mcl-HHx content >15 mol% and a MW average (Mw) < 2 × 105 Da. Solvents and precipitants were chosen regarding zeotrope formation, boiling point differences, and toxicity. Non-halogenated solvent-precipitant pairs were evaluated regarding the MW characteristics (MWCs) of the extracted polymer. Acetone and 2-propanol as a low toxic and zeotropic solvent-precipitant pair was evaluated at different extraction temperatures and multiple extraction times. The extraction process was further evaluated by using impure acetone for the extraction and implementing a multi-stage extraction process. Additionally, P(HB-co-HHx) extracted with three different solvents was characterized by 1H and 13C-APT NMR. The screening of precipitants resulted in a negative influence on the MWCs by ethanol precipitation for extractions with acetone and ethyl acetate, respectively. It was observed, that extractions with acetone at 70°C extracted a higher fraction of PHA from the cells compared to extractions at RT, but the Mw was decreased by 9% in average. Acetone with a 2-propanol fraction of up to 30% was still able to extract the polymer 95% as efficient as pure acetone. Additionally, when acetone and ethyl acetate were used in a multi-stage extraction process, a two-stage process was sufficient to extract 98–99% of the polymer from the cells. 1H and 13C-APT NMR analysis confirmed the monomer fraction and structure of the extracted polymers and revealed a random copolymer structure. The presented strategy can be further developed to an ecological and economically feasible PHA downstream process and thus contributes to the commercialization of low-cost PHAs.TU Berlin, Open-Access-Mittel – 2020BMBF, 031B0001C, Bioökonomie International 2014: PHABIO APP - Polyhydroxyalkanoate Biopolymere aus tierischen Abfallfetten für die Produktion von wertschöpfendem, biobasierten und abbauendem Plastik; Teilprojekt CBMBF, 031B0001B, Bioökonomie International 2014: PHABIO APP - Polyhydroxyalkanoate Biopolymere aus tierischen Abfallfetten für die Produktion von wertschöpfendem, biobasierten und abbauendem Plastik; Teilprojekt BBMBF, 031B0798C, Bioökonomie International 2017: PHABio-up - Polyhydroxyalkanoate Biopolymere aus tierischen Abfallfetten: Scale-up zur Realisierung einer industriellen Produktion - Teilvorhaben: Feedstock und Produktextraktio

An appeal for strengthening genomic pathogen surveillance to improve pandemic preparedness and infection prevention: the German perspective

The SARS-CoV-2 pandemic has highlighted the importance of viable infection surveillance and the relevant infrastructure. From a German perspective, an integral part of this infrastructure, genomic pathogen sequencing, was at best fragmentary and stretched to its limits due to the lack or inefficient use of equipment, human resources, data management and coordination. The experience in other countries has shown that the rate of sequenced positive samples and linkage of genomic and epidemiological data (person, place, time) represent important factors for a successful application of genomic pathogen surveillance. Planning, establishing and consistently supporting adequate structures for genomic pathogen surveillance will be crucial to identify and combat future pandemics as well as other challenges in infectious diseases such as multi-drug resistant bacteria and healthcare-associated infections. Therefore, the authors propose a multifaceted and coordinated process for the definition of procedural, legal and technical standards for comprehensive genomic pathogen surveillance in Germany, covering the areas of genomic sequencing, data collection and data linkage, as well as target pathogens. A comparative analysis of the structures established in Germany and in other countries is applied. This proposal aims to better tackle epi- and pandemics to come and take action from the “lessons learned” from the SARS-CoV-2 pandemic

Correction to: Two years later: Is the SARS-CoV-2 pandemic still having an impact on emergency surgery? An international cross-sectional survey among WSES members

Background: The SARS-CoV-2 pandemic is still ongoing and a major challenge for health care services worldwide. In the first WSES COVID-19 emergency surgery survey, a strong negative impact on emergency surgery (ES) had been described already early in the pandemic situation. However, the knowledge is limited about current effects of the pandemic on patient flow through emergency rooms, daily routine and decision making in ES as well as their changes over time during the last two pandemic years. This second WSES COVID-19 emergency surgery survey investigates the impact of the SARS-CoV-2 pandemic on ES during the course of the pandemic. Methods: A web survey had been distributed to medical specialists in ES during a four-week period from January 2022, investigating the impact of the pandemic on patients and septic diseases both requiring ES, structural problems due to the pandemic and time-to-intervention in ES routine. Results: 367 collaborators from 59 countries responded to the survey. The majority indicated that the pandemic still significantly impacts on treatment and outcome of surgical emergency patients (83.1% and 78.5%, respectively). As reasons, the collaborators reported decreased case load in ES (44.7%), but patients presenting with more prolonged and severe diseases, especially concerning perforated appendicitis (62.1%) and diverticulitis (57.5%). Otherwise, approximately 50% of the participants still observe a delay in time-to-intervention in ES compared with the situation before the pandemic. Relevant causes leading to enlarged time-to-intervention in ES during the pandemic are persistent problems with in-hospital logistics, lacks in medical staff as well as operating room and intensive care capacities during the pandemic. This leads not only to the need for triage or transferring of ES patients to other hospitals, reported by 64.0% and 48.8% of the collaborators, respectively, but also to paradigm shifts in treatment modalities to non-operative approaches reported by 67.3% of the participants, especially in uncomplicated appendicitis, cholecystitis and multiple-recurrent diverticulitis. Conclusions: The SARS-CoV-2 pandemic still significantly impacts on care and outcome of patients in ES. Well-known problems with in-hospital logistics are not sufficiently resolved by now; however, medical staff shortages and reduced capacities have been dramatically aggravated over last two pandemic years

Low-quality animal by-product streams for the production of PHA-biopolymers: fats, fat/protein-emulsions and materials with high ash content as low-cost feedstocks

Objective: The rapid accumulation of crude-oil based plastics in the environment is posing a fundamental threat to the future of mankind. The biodegradable and bio-based polyhydroxyalkanoates (PHAs) can replace conventional plastics, however, their current production costs are not competitive and therefore prohibiting PHAs from fulfilling their potential. Results: Different low-quality animal by-products, which were separated by thermal hydrolysis into a fat-, fat/protein-emulsion- and mineral-fat-mixture- (material with high ash content) phase, were successfully screened as carbon sources for the production of PHA. Thereby, Ralstonia eutropha Re2058/pCB113 accumulated the short- and medium-chain-length copolymer poly(hydroxybutyrate- co -hydroxyhexanoate) [P(HB- co -HHx)]. Up to 90 wt% PHA per cell dry weight with HHx-contents of 12–26 mol% were produced in shake flask cultivations. Conclusion: In future, the PHA production cost could be lowered by using the described animal by-product streams as feedstock.TU Berlin, Open-Access-Mittel – 2020BMBF, 031B0798A, Bioökonomie International 2017: PHABio-up - Polyhydroxyalkanoate Biopolymere aus tierischen Abfallfetten: Scale-up zur Realisierung einer industriellen ProduktionBMBF, 031B0798C, Bioökonomie International 2017: PHABio-up - Polyhydroxyalkanoate Biopolymere aus tierischen Abfallfetten: Scale-up zur Realisierung einer industriellen Produktion - Teilvorhaben: Feedstock und Produktextraktio

Terminal adenosyl transferase activity of posttranscriptional regulator HuR revealed by confocal on-bead screening

Posttranscriptional regulation and RNA metabolism have become central topics in the understanding of mammalian gene expression and cell signalling, with the 3' untranslated region emerging as the coordinating unit. The 3' untranslated region trans-acting factor Hu protein R (HuR) forms a central posttranscriptional pathway node bridging between AU-rich element-mediated processes and microRNA regulation. While (m)RNA control by HuR has been extensively characterized, the molecular mode of action still remains elusive. Here we describe the identification of the first RRM3 (RNA recognition motif 3) targeted low molecular weight HuR inhibitors from a one-bead-one-compound library screen using confocal nanoscanning. A further compound characterization revealed the presence of an ATP-binding pocket within HuR RRM3, associated with enzymatic activity. Centered around a metal-ion-coordinating DxD motif, the catalytic site mediates 3'-terminal adenosyl modification of non-polyadenylated RNA substrates by HuR. These findings suggest that HuR actively contributes to RNA modification and maturation and thereby shed an entirely new light on the role of HuR in RNA metabolism

Масштабирование процесса экстракции сополимера П(ГБ‑co-ГГ) негалогенированными растворителями

Biobased and biodegradable polyhydroxyalkanoates (PHAs) are promising alternatives to common plastics. Due to their high production costs, only a minimal share of global plastic production is composed of PHA. A major contributor to the high costs minimizing the potential to occupy a larger market share is the downstream process. To obtain high recovery yields and pure products, most approaches rely on large amounts of solvents. While short-chain-length PHA (scl-PHA) is poorly soluble in nonhalogenated solvents, medium-chain-length PHA (mcl-PHA) was shown to be soluble in nonhalogenated solvents. In this study, an approach to recover poly(hydroxybutyrate-co-hydroxyhexanoate) with acetone and 2-propanol was scaled up 30-fold to 300 g of lyophilized cells per recovery cycle. High PHA purities of 90–100 % were reached from extractions at moderate temperatures from 30–58 °C. In two-stage extractions, up to 100 % PHA was recovered, while the molecular weight was not reduced. Solvents were recovered by distillation in a concentration step and after precipitation. Furthermore, the material properties were analyzed. PHA recovered from the distillation bottom had an increased HHx content compared to the first and second extractions using recovered solvents and was of low purity, indicating efficient and pure precipitation of the recovered PHA during the 2-stage extractionsСинтезируемые микроорганизмами биоразлагаемые полигидроксиалканоаты (ПГА) являются многообещающей альтернативой обычным пластмассам. Однако высокая стоимость ПГА ограничивает объемы их мирового производства. Одной из основных причин высоких затрат, сводящих к минимуму возможность занять большую долю рынка, является сложный и дорогостоящий процесс извлечения полимеров из клеточной биомассы. Для получения высоких выходов извлечения и чистых образцов полимеров используются большие количества растворителей. При этом известно, что короткоцепочечные ПГА плохо растворяются в негалогенированных растворителях, в то время как среднецепочечные – растворяются. В этом исследовании процесс извлечения сополимера гидроксибутирата и гидроксигексаноата с использованием ацетона и 2-пропанола масштабирован в 30 раз (до 300 г лиофилизированной клеточной массы на один цикл извлечения). Высокая чистота ПГА (90–100 %) достигнута при проведении экстракции при умеренных температурах от 30 до 58 °C. При двукратной экстракции полнота извлечения полимера достигала 100 % без снижения значений молекулярной массы. Растворители возвращали для повторных циклов перегонкой на стадии концентрирования и после осаждения извлеченного полимера. Проанализированы свойства полученных образцов ПГА. Полимер, извлеченный из остаточной от дистилляции фракции, по сравнению с полимером, полученным в результате двукратной экстракции с повторным использованием растворителей, имел повышенное содержание фракции мономеров гексаноата и низкую степень чистоты. Это свидетельствует об эффективности осаждения полимера, извлеченного в процессе двукратной экстракци

Treatment effect of remdesivir on the mortality of hospitalised COVID-19 patients in Switzerland across different patient groups: a tree-based model analysis

AIMS OF THE STUDY: Remdesivir has shown benefits against COVID-19. However, it remains unclear whether, to what extent, and among whom remdesivir can reduce COVID-19-related mortality. We explored whether the treatment response to remdesivir differed by patient characteristics. METHODS: We analysed data collected from a hospital surveillance study conducted in 21 referral hospitals in Switzerland between 2020 and 2022. We applied model-based recursive partitioning to group patients by the association between treatment levels and mortality. We included either treatment (levels: none, remdesivir within 7 days of symptom onset, remdesivir after 7 days, or another treatment), age and sex, or treatment only as regression variables. Candidate partitioning variables included a range of risk factors and comorbidities (and age and sex unless included in regression). We repeated the analyses using local centring to correct the results for the propensity to receive treatment. RESULTS: Overall (n = 21,790 patients), remdesivir within 7 days was associated with increased mortality (adjusted hazard ratios 1.28–1.54 versus no treatment). The CURB-65 score caused the most instability in the regression parameters of the model. When adjusted for age and sex, patients receiving remdesivir within 7 days of onset had higher mortality than those not treated in all identified eight patient groups. When age and sex were included as partitioning variables instead, the number of groups increased to 19–20; in five to six of those branches, mortality was lower among patients who received early remdesivir. Factors determining the groups where remdesivir was potentially beneficial included the presence of oncological comorbidities, male sex, and high age. CONCLUSIONS: Some subgroups of patients, such as individuals with oncological comorbidities or elderly males, may benefit from remdesivir

Two years later: Is the SARS-CoV-2 pandemic still having an impact on emergency surgery? An international cross-sectional survey among WSES members

Background The SARS-CoV-2 pandemic is still ongoing and a major challenge for health care services worldwide. In the first WSES COVID-19 emergency surgery survey , a strong negative impact on emergency surgery (ES) had been described already early in the pandemic situation. However, the knowledge is limited about current effects of the pandemic on patient flow through emergency rooms, daily routine and decision making in ES as well as their changes over time during the last two pandemic years. This second WSES COVID-19 emergency surgery survey investigates the impact of the SARS-CoV-2 pandemic on ES during the course of the pandemic. Methods A web survey had been distributed to medical specialists in ES during a four-week period from January 2022, investigating the impact of the pandemic on patients and septic diseases both requiring ES, structural problems due to the pandemic and time-to-intervention in ES routine. Results 367 collaborators from 59 countries responded to the survey. The majority indicated that the pandemic still significantly impacts on treatment and outcome of surgical emergency patients (83.1% and 78.5%, respectively). As reasons, the collaborators reported decreased case load in ES (44.7%), but patients presenting with more prolonged and severe diseases, especially concerning perforated appendicitis (62.1%) and diverticulitis (57.5%). Otherwise, approximately 50% of the participants still observe a delay in time-to-intervention in ES compared with the situation before the pandemic. Relevant causes leading to enlarged time-to-intervention in ES during the pandemic are persistent problems with in-hospital logistics, lacks in medical staff as well as operating room and intensive care capacities during the pandemic. This leads not only to the need for triage or transferring of ES patients to other hospitals, reported by 64.0% and 48.8% of the collaborators, respectively, but also to paradigm shifts in treatment modalities to non-operative approaches reported by 67.3% of the participants, especially in uncomplicated appendicitis, cholecystitis and multiple-recurrent diverticulitis. Conclusions The SARS-CoV-2 pandemic still significantly impacts on care and outcome of patients in ES. Well-known problems with in-hospital logistics are not sufficiently resolved by now; however, medical staff shortages and reduced capacities have been dramatically aggravated over last two pandemic years