Two glycerol uptake systems contribute to the high osmotolerance of Zygosaccharomyces rouxii

The accumulation of glycerol is essential for yeast viability upon hyperosmotic stress. Here we show that the osmotolerant yeast Zygosaccharomyces rouxii has two genes, ZrSTL1 and ZrSTL2, encoding transporters mediating the active uptake of glycerol in symport with protons, contributing to cell osmotolerance and intracellular pH homeostasis. The growth of mutants lacking one or both transporters is affected depending on the growth medium, carbon source, strain auxotrophies, osmotic conditions and the presence of external glycerol. These transporters are localised in the plasma membrane, they transport glycerol with similar kinetic parameters and besides their expected involvement in the cell survival of hyperosmotic stress, they surprisingly both contribute to an efficient survival of hypoosmotic shock and to the maintenance of intracellular pH homeostasis under non-stressed conditions. Unlike STL1 in Sa. cerevisiae, the two Z. rouxii STL genes are not repressed by glucose, but their expression and activity are downregulated by fructose and upregulated by non-fermentable carbon sources, with ZrSTL1 being more influenced than ZrSTL2. In summary, both transporters are highly important, though Z. rouxii CBS 732(T) cells do not use external glycerol as a source of carbon.The help of Dr. P. Ergang with the real-time PCR experiments is gratefully acknowledged. We thank O. Zimmermannova for critical reading of the paper. This work was supported by the following grants: Grant Agency of the Czech Republic P503/ 10/0307, institutional concept RVO:6798582, Grant Agency of the Charles University 299611/2011/B-Bio/PrF, an Lifelong Learning Programme ERASMUS practical placement grant and by Fundo Europeu de Desenvolvimento Regional – Programa Operacional de Fatores de Competitividade – COMPETE and by national funds from Fundação para a Ciência e Tecnologia through the project PEstC/BIA/UI4050/ 2011.info:eu-repo/semantics/publishedVersio

Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

Background Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide.Methods A multimethods analysis was performed as part of the GlobalSurg 3 study-a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital.Findings Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3.85 [95% CI 2.58-5.75]; p<0.0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63.0% vs 82.7%; OR 0.35 [0.23-0.53]; p<0.0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer.Interpretation Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised

Some new porphodimethene chemistry: Synthesis of meso-formylporphyrins

Treatment of dipyrromethane-1,9-dicarboxylic acids with triethyl orthoformate and trifluoroacetic acid gives the expected symmetrically substituted porphyrin, along with small amounts of meso-formyl and meso-diformyl-porphyrins. The 5,15 regioselectivity of the formyl groups in the disubstituted product and NOE experiments suggest that serendipitous formylation takes place at the intermediate porphodimethene stage. © 1994

Oxidation of Monoterpenes Catalysed by a Water-Soluble Mn-III PEG-Porphyrin in a Biphasic Medium

© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim It is well established that the transformation of abundant and cheap natural products, such as terpenoids, can produce other more valuable compounds. Thymoquinone, which has a commercial value significantly higher than that of its precursors, can be obtained by oxidation of carvacrol and thymol. In this work, a new water-soluble Mn III PEG-porphyrin is reported as catalyst in a water/hexane (1:1) biphasic medium for the oxidation of carvacrol and thymol into thymoquinone. The reactions were performed using tert-butyl hydroperoxide as oxidant in the presence of ammonium acetate as co-catalyst, reaching 94 and 78 % of conversion after 5 h of reaction for thymol and carvacrol, respectively. Experiments with oregano essential oil as substrate revealed selective transformation of thymol and carvacrol into thymoquinone. The main advantage of this biphasic system based on a water-soluble catalyst and on substrates and products soluble in hexane, is the straightforward isolation, recovery and recycling of the catalyst by simple phase separation. Recycling studies of the Mn III PEG-porphyrin using thymol as substrate showed high conversion values throughout four catalytic cycles.status: publishe

Galactodendritic porphyrinic conjugates as new biomimetic catalysts for oxidation reactions

This work employed [5,10,15,20-tetrakis(pentafluorophenyl)porphyrin] ([H-2(TPPF20)], H(2)P1) as the platform to prepare a tetrasubstituted galactodendritic conjugate porphyrin (H(2)P3). After metalation with excess copper(II) acetate, H(2)P3 afforded a new solid porphyrin material, Cu(4)CuP3S. This work also assessed the ability of the copper(II) complex (CuP3) of H(2)P3 to coordinate with zinc(II) acetate, to yield the new material Zn4CuP3S. UVvisible, Fourier transform infrared, and electron paramagnetic resonance spectroscopies aided full characterization of the synthesized solids. (Z)-Cyclooctene epoxidation under heterogeneous conditions helped to evaluate the catalytic activity of Cu(4)CuP3S and Zn(4)CuP3S. The efficiency of Cu(4)CuP3S in the oxidation of another organic substrate, catechol, was also investigated. According to the results obtained in the heterogeneous process, Cu(4)CuP3S mimicked the activity of cytochrome P-450 and catecholase. In addition, Cu(4)CuP3S was reusable after recovery and reactivation. The data obtained herein were compared with the results achieved for the copper complex (CuP1) of [H-2(TPPF20)] and for CuP3 under homogeneous conditions