Self-assembly of the anti-fungal polyene amphotericin B into giant helically-twisted nanotapes

The amphiphilic polyene amphotericin B, a powerful treatment for systemic fungal infections, is shown to exhibit a critical aggregation concentration, and to form giant helically-twisted nanostructures via self-assembly in basic aqueous solution

Global patient outcomes after elective surgery: prospective cohort study in 27 low-, middle- and high-income countries.

BACKGROUND: As global initiatives increase patient access to surgical treatments, there remains a need to understand the adverse effects of surgery and define appropriate levels of perioperative care. METHODS: We designed a prospective international 7-day cohort study of outcomes following elective adult inpatient surgery in 27 countries. The primary outcome was in-hospital complications. Secondary outcomes were death following a complication (failure to rescue) and death in hospital. Process measures were admission to critical care immediately after surgery or to treat a complication and duration of hospital stay. A single definition of critical care was used for all countries. RESULTS: A total of 474 hospitals in 19 high-, 7 middle- and 1 low-income country were included in the primary analysis. Data included 44 814 patients with a median hospital stay of 4 (range 2-7) days. A total of 7508 patients (16.8%) developed one or more postoperative complication and 207 died (0.5%). The overall mortality among patients who developed complications was 2.8%. Mortality following complications ranged from 2.4% for pulmonary embolism to 43.9% for cardiac arrest. A total of 4360 (9.7%) patients were admitted to a critical care unit as routine immediately after surgery, of whom 2198 (50.4%) developed a complication, with 105 (2.4%) deaths. A total of 1233 patients (16.4%) were admitted to a critical care unit to treat complications, with 119 (9.7%) deaths. Despite lower baseline risk, outcomes were similar in low- and middle-income compared with high-income countries. CONCLUSIONS: Poor patient outcomes are common after inpatient surgery. Global initiatives to increase access to surgical treatments should also address the need for safe perioperative care. STUDY REGISTRATION: ISRCTN5181700

Determination of organophosphorus pesticide residues in fruits by gas chromatography with ITD and NPD detection

Several widely used organophosphorus insecticides, diazinon, methyl-parathion, fenitrothion, malathion, fenthion and methidathion were selected for inclusion in this work. A comparative study of the multiresidue determination of these compounds in citrus fruit and grapes has been carried out by gas chromatography with nitrogen-phosphorus and ion trap detection. Samples were spiked with 0.1, 0.5 and 1 mg kg-1 of each pesticide and blended in a Sorvall homogeniser with ethyl acetate. Column clean-up on Florisil was necessary for citrus peel extracts. The average recoveries varied from 81 to 107% with a relative standard deviation between 0.3 and 9.5% for GC-ITD and from 86 to 104% with a relative standard deviation ranging from 1.4 to 8.0% for GC-NPD. The detection limit of the method was 10 ng g-1 or less for each organophosphorus insecticide, with both detectors. This method was applied to the analysis of treated lemons and 0.25 mg kg-1 of fenitrothion in fruit was detected a week after treatment and identified by its mass spectrum. The results obtained showed that the proposed methods are reproducible and sensitive enough for the simultaneous determination of these insecticides in fruits at residue level

Alachlor persistence under Spanish field conditions and applicability of simulation models

Alachlor persistence was studied in three corn fields from two regions of Spain. The effect of soil temperature and soil moisture content on the rates of alachlor degradation was measured under controlled conditions in soil samples from the same fields. Laboratory data in conjunction with meteorological records were used in two computer models to predict alachlor persistence in the fields. The Walker model was used with a correction on the Linacre equation to take into account the Spanish field conditions. The degradation predicted with this model was faster than the data measured in the fields. The LEACHP v.3 model was used, with a modification in the subroutine that simulates the influence of temperature and moisture content on the degradation component. There was an acceptable agreement between measured and predicted residue levels with the LEACHP model in the three fields. Alachlor persistence and model prediction were discussed. © 1994 Williams & Wilkins

Analysis of triallate residues in cereals and soil by gas chromatography with ion-trap detection

Triallate residues in barley seedlings and soil samples were determined by gas chromatography with ion-trap detection. Soil was extracted with methanol on a mechanical shaker, and plants were extracted with acetonitrile in a Sorvall homogenizer. After evaporation of the organic solvents, the residue was dissolved in hexane, and plants extracts were cleaned-up on an alumina column. Gas chromatographic analysis was carried out using a BP-1 fused-silica capillary column with helium as carrier gas. To quantitate residues the total-ion chromatogram was obtained and then the selected-ion monitoring chromatograms were displayed at m/z 86 for triallate and at m/z 154 for the internal standard, methyl-(4-amino-2-chloro)-benzoate. The average recovery through the method from barley and soil samples was always higher than 80%. The limit of detection in the selected-ion mode was 0.01 mg/kg. Barley and soil samples treated with triallate were also analysed. A good agreement was observed between results obtained by this method and by gas chromatography with nitrogen-phosphorus detection. © 1991

Determination of fungicide residues in peach trees

The residue analyses of three fungicides, thiram, captan and benomyl, have been accomplished in peach trees. Thiram was extracted with hexaneethyl acetate (8020 v/v) and determined after a column cleanup by reverse-phase HPLC with a mixture of acetonitrile0.3 ammonia at 280 nm. Captan was extracted with acetonitrilewater (21) and determined by GLC-ECD after a partition and a column clean-up. Benomyl was extracted with ethyl acetate and determined, as MBC, by reverse-phase HPLC with methanol0.3 ammonia, after a partition and a column clean-up. Recoveries through the methods were always higher than 70%. The detection limits were 0.5 ppm for thiram, 0.02 ppm for captan and 0.2 ppm for benomyl, based on a 5 g sample. Residue levels in peach twigs, treated with fungicide solutions, are reported.© 1989, Taylor & Francis Group, LLC. All rights reserved

Enhancement of wheat tolerance to triallaic with the safener MON 5501

The triallate tolerance of wheat (Triticum aestivum L.) cultivars Marius and Mexicali was determined under growth‐chamber conditions. Mexicali was found to tolerate triallate at levels about fourfold higher than Marius. The susceptible wheat cultivar was protected against triallate by seed treatment with MON 5501. The herbicide concentration in the aerial part of the plants was determined by gas chromatography. Triallate levels were similar in both cultivars treated with 0.5 mg 1−1 of triallate. The safener did not affect the triallate content per plant in the susceptible wheat cultivar treated with 1 mg 1−1 of herbicide. Augmentation de la tolerance du blé au triallate avec le phytoprotecteur MON 5501 La tolerance au triallate des cultivars de ble Marius et Mexicali a été déterminée en chambre climatique. Mexicali s'est avéré 4 fois plus tolérant que Marius. Le cultivar de blé sensible a été protege du triallate par un traitement des grains avec MON 5501. La concentration en herbicide dans la partie aérienne des plantes a été determined par chromatographie gazeuse. Les taux de triallate ont été equivalents chez les 2 cultivars traites avec 0,5 mg l−1 de triallate. Le phytoprotecteur n'a pas affecté lateneur en triallate par plante chez le cultivar sensible traite avec 1 mg 1−1 d'herbicide. Verbesserung der Toleranz von Weizen gegenuber Triallat mil dem Antidot MON 5501 Die Triallat‐Toleranz der Weizensorten ‘Marius’ und ‘Mexicali’ wurde im Phytotron bestimmt. ‘Mexicali’ war etwa 4mal toleranter als ‘Marius’. Die empfindliche Weizensorte wurde durch Beizung mit MON 5501 gegen Triallat geschützt. Die Herbizidkonzentration in den oberirdischen Pflanzenteilen wurde gaschromatographisch bestimmt Der Wirkstoff‐Gehalt war in beiden mit 0,5 mg 1−1 Triallat behandelten Sorten ahnlich hoch. Das Antidot hatte keinen Einfluβ auf den Triallat‐Gehalt der empfindlichen Weizensorte, die mit 1 mg 1−1 behandelt worden war. Copyright © 1992, Wiley Blackwell. All rights reserve

Determination of cereal herbicide residues in environmental samples by gas chromatography

Gas chromatographic analysis of cereal herbicide residues in water, soil, plant and air is reviewed. Herbicides widely used in spring and winter cereals, i.e.;phenoxyacids, benzonitriles, ureas, triazines, dinitroanilines, chloroacetamides and thiocarbamates, are considered. The main procedures used in the residue analysis, extraction, clean-up, derivatization and gas chromatographic determination are summarized and discussed