Decolorization of synthetic dyes by laccase immobilized on epoxy-activated carriers

The Myceliophthora thermophila laccase was covalently immobilized on polymethacrylate-based polymers (Sepabeads EC-EP3 and Dilbeads NK) activated with epoxy groups. The enzyme immobilized on Sepabeads EC-EP3 exhibited notable activity (203 U/g) along with remarkably improved stability towards pH, temperature and storage time, but no increased resistance to organic solvents. In addition, the immobilized laccase also showed good operational stability, maintaining 84% of its initial activity after 17 cycles of oxidation of ABTS. The immobilized biocatalyst was applied to the decolorization of six synthetic dyes. Immobilized laccase retained 41% activity in the decolorization of Methyl Green in a fixed-bed reactor after five cycles. The features of these biocatalysts are very attractive for their application on the decolorization of dyes in the textile industry in batch and continuous fixed-bed bioreactors. To our knowledge, this is the first report on immobilization of laccase on Sepabeads carriers and its efficient dyes decolorization.We thank Drs. Moreno Daminati and Paolo Caimi (Resindion) and Vyasa Rajasekar (DilComplex) for providing us Sepabeads EC-EP3 and Dilbeads NK polymers, respectively. We are grateful to Ramiro Martínez (Novozymes A/S, Spain) for DeniLite II S samples. This material is based upon work founded by Spanish MEC (Projects VEM2004-08559 and CTQ2005-08925-C02-02/PPQ); European Union (Project NMP2-CT-2006-026456) and CSIC (Project 200580M121). Spanish MEC is also thanked for the post-doctoral fellowship (SB2004-0011) of Dr. A. Kunamneni and for the Ramon y Cajal contracts of Drs. S. Camarero and M. Alcalde.This material is based upon work financed by Spanish MEC (Projects VEM2004-08559 and CTQ2005-08925-C02-02/PPQ); European Union (Project NMP2-CT-2006-026456) and CSIC (Project 200580M121). Spanish MEC is also thanked for the post-doctoral fellowship (SB2004-0011) of Dr. A. Kunamneni and for the Ramon y Cajal contracts of Drs. S. Camarero and M. Alcalde.Peer reviewe

Severe gastric variceal haemorrhage due to splenic artery thrombosis and consecutive arterial bypass

<p>Abstract</p> <p>Background</p> <p>Upper gastrointestinal haemorrhage is mainly caused by ulcers. Gastric varicosis due to portal hypertension can also be held responsible for upper gastrointestinal bleeding. Portal hypertension causes the development of a collateral circulation from the portal to the caval venous system resulting in development of oesophageal and gastric fundus varices. Those may also be held responsible for upper gastrointestinal haemorrhage.</p> <p>Case presentation</p> <p>In this study, we describe the case of a 69-year-old male with recurrent severe upper gastrointestinal bleeding caused by arterial submucosal collaterals due to idiopathic splenic artery thrombosis. The diagnosis was secured using endoscopic duplex ultrasound and angiography. The patient was successfully treated with a laparoscopic splenectomy and complete dissection of the short gastric arteries, resulting in the collapse of the submucosal arteries in the gastric wall. Follow-up gastroscopy was performed on the 12^thpostoperative week and showed no signs of bleeding and a significant reduction in the arterial blood flow within the gastric wall. Subsequent follow-up after 6 months also showed no further gastrointestinal bleeding as well as subjective good quality of life for the patient.</p> <p>Conclusion</p> <p>Submucosal arterial collaterals must be excluded by endosonography via endoscopy in case of recurrent upper gastrointestinal bleeding. Laparoscopic splenectomy provides adequate treatment in preventing any recurrent bleeding, if gastric arterial collaterals are caused by splenic artery thrombosis.</p

Optimizing community-driven development through sage tradition in Cameroon

Powering community development requires a re-invention of traditional authority. This paper interrogates this proposition: how does sage tradition engender social resilience and what is the impact of traditional authority on the modern governance architecture? Sage tradition construed culturally as elder-led authority is anchored on wisdom and respect for elders—a pivotal asset in community development transactions. Informed by indigenous knowledge, social capital and asset-based concepts, an empirical account of strategic leadership by the elderly is proffered, uncovering indigenous governance in the North West Region, Cameroon. A pyramidal power structure validates village elders as key players in advancing social justice. They offer counsel and arbitrate in community affairs and mobilise community members for infrastructure provision—community halls, equipping schools, digging roads, building bridges and supply of fresh water. Though elder esteemed traditions prove perfunctory, findings show communities are benefiting from the accumulated, incremental cultural assets factored into local development. The paper concludes that thriving cultural assets should be amalgamated through a policy drive that taps into the utility of traditional authority, in synergy with modern state institutions to bolster social development, address poverty and social inequality

Gentamicin supplemented polyvinylidenfluoride mesh materials enhance tissue integration due to a transcriptionally reduced MMP-2 protein expression

<p>Abstract</p> <p>Background</p> <p>A beneficial effect of gentamicin supplemented mesh material on tissue integration is known. To further elucidate the interaction of collagen and MMP-2 in chronic foreign body reaction and to determine the significance of the MMP-2-specific regulatory element (RE-1) that is known to mediate 80% of the MMP-2 promoter activity, the spatial and temporal transcriptional regulation of the MMP-2 gene was analyzed at the cellular level.</p> <p>Methods</p> <p>A PVDF mesh material was surface modified by plasma-induced graft polymerization of acrylic acid (PVDF+PAAc). Three different gentamicin concentrations were bound to the provided active sites of the grafted mesh surfaces (2, 5 and 8 μg/mg). 75 male transgenic MMP-2/LacZ mice harbouring the LacZ reporter gene under control of MMP-2 regulatory sequence -1241/+423, excluding the RE-1 were randomized to five groups. Bilateral of the abdominal midline one of the five different meshes was implanted subcutaneously in each animal. MMP-2 gene transcription (anti-ß-galactosidase staining) and MMP-2 protein expression (anti-MMP-2 staining) were analyzed semiquantitatively by immunohistochemistry 7, 21 and 90 days after mesh implantation. The collagen type I/III ratio was analyzed by cross polarization microscopy to determine the quality of mesh integration.</p> <p>Results</p> <p>The perifilamentary ß-galactosidase expression as well as the collagen type I/III ratio increased up to the 90^thday for all mesh modifications, whereas no significant changes could be observed for MMP-2 protein expression between days 21 and 90. Both the 5 and 8 μg/mg gentamicin group showed significantly reduced levels of ß-galactosidase expression and MMP-2 positive stained cells when compared to the PVDF group on day 7, 21 and 90 respectively (5 μg/mg: p < 0.05 each; 8 μg/mg: p < 0.05 each). Though the type I/III collagen ratio increased over time for all mesh modifications significant differences to the PVDF mesh were only detected for the 8 μg/mg group at all 3 time points (p < 0.05 each).</p> <p>Conclusions</p> <p>Our current data indicate that lack of RE-1 is correlated with increased mesh induced MMP-2-gene expression for coated as well as for non-coated mesh materials. Gentamicin coating reduced MMP-2 transcription and protein expression. For the 8 μg/mg group this effect is associated with an increased type I/III collagen ratio. These findings suggest that gentamicin is beneficial for tissue integration after mesh implantation, which possibly is mediated via RE-1.</p

Situation, Figuration und Gewalt. Versuch eines gewaltsoziologischen Dialoges zwischen Randall Collins und Norbert Elias am Beispiel sexueller Kriegsgewalt

Ebner J, Stopfinger M. Situation, Figuration und Gewalt. Versuch eines gewaltsoziologischen Dialoges zwischen Randall Collins und Norbert Elias am Beispiel sexueller Kriegsgewalt. Österreichische Zeitschrift für Soziologie. 2020;45(S1):43-67.In diesem Beitrag werden zwei in der soziologischen Gewaltforschung etablierte Ansätze – die mikrosoziologisch-situationistische Gewalttheorie von Randall Collins und die figurations- bzw. prozesssoziologische Perspektive von Norbert Elias – auf ihre Eignung für die Analyse von sexueller Kriegsgewalt überprüft. Nach einer kurzen Diskussion des Forschungsstandes zu sexueller Kriegsgewalt wird dieses Thema einmal mit Collins und einmal mit Elias beleuchtet. Danach werden die beiden Zugänge einander gegenübergestellt, um Unterschiede und Gemeinsamkeiten herauszuarbeiten. Darauf aufbauend wird versucht, die Fruchtbarkeit eines „pragmatischen Dialoges“ zwischen einem mikro- und einem figurationssoziologisch inspirierten Ansatz auszuloten. Abschließend wird diskutiert, welche Folgerungen sich daraus für die Forschung zu sexueller Kriegsgewalt ergeben.In this paper, two approaches established in sociological violence research – Randall Collins’ micro-sociological theory of violence and Norbert Elias’ figuration- and process-sociological perspective—are examined for their suitability for the analysis of sexual violence in war. After a brief discussion of the current state of research on sexual violence in war, this topic will be examined once with Collins and once with Elias. The two approaches are then juxtaposed in order to highlight differences and similarities. Building on this, the fruitfulness of a “pragmatic dialogue” between a micro- and a figuration-sociologically inspired approach will be explored. The concluding section discusses the implications for research on sexual violence in war