Human Galectins Induce Conversion of Dermal Fibroblasts into Myofibroblasts and Production of Extracellular Matrix: Potential Application in Tissue Engineering and Wound Repair

Members of the galectin family of endogenous lectins are potent adhesion/growth-regulatory effectors. Their multi-functionality opens possibilities for their use in bioapplications. We studied whether human galectins induce the conversion of human dermal fibroblasts into myofibroblasts (MFBs) and the production of a bioactive extracellular matrix scaffold is suitable for cell culture. Testing a panel of galectins of all three subgroups, including natural and engineered variants, we detected activity for the proto-type galectin-1 and galectin-7, the chimera-type galectin-3 and the tandem-repeat-type galectin-4. The activity of galectin-1 required the integrity of the carbohydrate recognition domain. It was independent of the presence of TGF-beta 1, but it yielded an additive effect. The resulting MFBs, relevant, for example, for tumor progression, generated a matrix scaffold rich in fibronectin and galectin-1 that supported keratinocyte culture without feeder cells. Of note, keratinocytes cultured on this substratum presented a stem-like cell phenotype with small size and keratin-19 expression. In vivo in rats, galectin-1 had a positive effect on skin wound closure 21 days after surgery. In conclusion, we describe the differential potential of certain human galectins to induce the conversion of dermal fibroblasts into MFBs and the generation of a bioactive cell culture substratum. Copyright (C) 2011 S. Karger AG, Base

Qualitative aspects and validation of a screening method for pesticides in vegetables and fruits based on liquid chromatography coupled to full scan high resolution (Orbitrap) mass spectrometry

The analytical capabilities of liquid chromatography with single-stage high-resolution mass spectrometry have been investigated with emphasis on qualitative aspects related to selective detection during screening and to identification. The study involved 21 different vegetable and fruit commodities, a screening database of 556 pesticides for evaluation of false positives, and a test set of 130 pesticides spiked to the commodities at 0.01, 0.05, and 0.20 mg/kg for evaluation of false negatives. The final method involved a QuEChERS-based sample preparation (without dSPE clean up) and full scan acquisition using alternating scan events without/with fragmentation, at a resolving power of 50,000. Analyte detection was based on extraction of the exact mass (±5 ppm) of the major adduct ion at the database retention time ±30 s and the presence of a second diagnostic ion. Various options for the additional ion were investigated and compared (other adduct ions, M + 1 or M + 2 isotopes, fragments). The two-ion approach for selective detection of the pesticides in the full scan data was compared with two alternative approaches based on response thresholds. Using the two-ion approach, the number of false positives out of 11,676 pesticide/commodity combinations targeted was 36 (0.3 %). The percentage of false negatives, assessed for 2,730 pesticide/commodity combinations, was 13 %, 3 %, and 1 % at the 0.01-, 0.05-, and 0.20-mg/kg level, respectively (slightly higher with fully automated detection). Following the SANCO/12495/2011 protocol for validation of screening methods, the screening detection limit was determined for 130 pesticides and found to be 0.01, 0.05, and ≥0.20 mg/kg for 86, 30, and 14 pesticides, respectively. For the detected pesticides in the spiked samples, the ability for unambiguous identification according to EU criteria was evaluated. A proposal for adaption of the criteria was made

3D pic simulations of collisionless shocks at lunar magnetic anomalies and their role in forming lunar swirls

The authors would like to thank the Science and Technology Facilities Council for fundamental physics and computing resources that were provided by funding from STFC’s Scientific Computing Department, and would like to thank the European Research Council (ERC 2010 AdG Grant 267841) and FCT (Portugal) grants SFRH/BD/75558/2010 for support.Investigation of the lunar crustal magnetic anomalies offers a comprehensive long-term data set of observations of small-scale magnetic fields and their interaction with the solar wind. In this paper a review of the observations of lunar mini-magnetospheres is compared quantifiably with theoretical kinetic-scale plasma physics and 3D particle-in-cell simulations. The aim of this paper is to provide a complete picture of all the aspects of the phenomena and to show how the observations from all the different and international missions interrelate. The analysis shows that the simulations are consistent with the formation of miniature (smaller than the ion Larmor orbit) collisionless shocks and miniature magnetospheric cavities, which has not been demonstrated previously. The simulations reproduce the finesse and form of the differential proton patterns that are believed to be responsible for the creation of both the "lunar swirls" and "dark lanes." Using a mature plasma physics code like OSIRIS allows us, for the first time, to make a side-by-side comparison between model and space observations. This is shown for all of the key plasma parameters observed to date by spacecraft, including the spectral imaging data of the lunar swirls. The analysis of miniature magnetic structures offers insight into multi-scale mechanisms and kinetic-scale aspects of planetary magnetospheres.Publisher PDFPeer reviewe

Boronic acids for sensing and other applications - a mini-review of papers published in 2013

Boronic acids are increasingly utilised in diverse areas of research. Including the interactions of boronic acids with diols and strong Lewis bases as fluoride or cyanide anions, which leads to their utility in various sensing applications. The sensing applications can be homogeneous assays or heterogeneous detection. Detection can be at the interface of the sensing material or within the bulk sample. Furthermore, the key interaction of boronic acids with diols allows utilisation in various areas ranging from biological labelling, protein manipulation and modification, separation and the development of therapeutics. All the above uses and applications are covered by this mini-review of papers published during 2013

In vitro susceptibility of Plasmodium falciparum isolates from Abidjan (Côte d'Ivoire) to artemisinin, chloroquine, dihydroartemisinin and pyronaridine

Côte d'Ivoire is an endemic area for Plasmodium falciparum malaria, with perennial transmission in the southern forest and seasonal transmission in the northern savannah. Change of first-line treatment of uncomplicated malaria to artemisinin-combination therapy (ACT) is widespread in the country as elsewhere in Africa. The present study was conducted to assess the in vitro response of Plasmodium. falciparum to antimalarial drugs currently used in the country (chloroquine, artemisinin and dihydroartemisinin) and new drugs that could be used in the near future (pyronaridine) and to analyse the pattern of cross-resistance between these drugs. The standard in vitro drug sensitivity microtechnique recommended by the World Health Organization was used to assess the sensitivity of Plasmodium falciparum isolates collected in Abidjan (Côte d'Ivoire) between April and December 2006. Of 128 in vitro tests performed, 112 (87.5%) were successful. Among them, 32, 27, 25, and 28 P. falciparum isolates grew satisfactorily and yield interpretable results for chloroquine, pyronaridine, artemisinin, and dihydroartemisinin respectively. The proportions of resistant isolates were 56.2% for chloroquine, 48% for pyronaridine, 36% for artemisinin and 3.6% for dihydroartemisinin. The most potent drug was dihydroartemisinin with a geometric mean IC50 of 2.72 nM ranged from 1.45 to 3.99 nM. No multi-resistant isolates (showing resistance to more than three drugs) were found. A positive correlation was found between the IC50 values for the following drugs: chloroquine and pyronaridine (r=0.45), pyronaridine and dihydroartemisinin (r=0.40), chloroquine and artemisinin (r=0.68), artemisinin and dihydroartemisinin (r=0.62). Data suggested cross-resistance between these drugs and warrant an improved surveillance programme for drug resistance to malaria in Côte d'Ivoire

In vitro susceptibility of Plasmodium falciparum isolates from Abidjan (Côte d’Ivoire) to artemisinin, chloroquine, dihydroartemisinin and pyronaridine

Côte d’Ivoire is an endemic area for Plasmodium falciparum malaria, with perennial transmission in the southern forest and seasonal transmission in the northern savannah. Change of first-line treatment of uncomplicated malaria to artemisinin-combination therapy (ACT) is widespread in the country as elsewhere in Africa. The present study was conducted to assess the in vitro response of Plasmodium. falciparum to antimalarial drugs  currently used in the country (chloroquine, artemisinin and dihydroartemisinin) and new drugs that could be used in the near future (pyronaridine) and to analyse the pattern of cross-resistance between these drugs. The standard in vitro drug sensitivity microtechnique recommended by the World Health Organization was used to assess the sensitivity of Plasmodium falciparum isolates collected in Abidjan (Côte d’Ivoire) between April and December 2006. Of 128 in vitro tests performed, 112 (87.5%) were successful. Among them, 32, 27, 25, and 28 P. falciparum isolates grew satisfactorily and yield interpretable results for chloroquine, pyronaridine, artemisinin, and dihydroartemisinin respectively. The proportions of resistant isolates were 56.2% for chloroquine, 48% for pyronaridine, 36% for artemisinin and 3.6% for dihydroartemisinin. The most potent drug was dihydroartemisinin with a geometric mean IC50 of 2.72 nM ranged from 1.45 to 3.99 nM. No multi-resistant isolates (showing resistance to more than three drugs) were found. A positive correlation was found between the IC50 values for the following drugs: chloroquine and pyronaridine (r=0.45), pyronaridine and dihydroartemisinin (r=0.40), chloroquine and artemisinin (r=0.68), artemisinin and dihydroartemisinin (r=0.62). Data suggested cross-resistance between these drugs and warrant an improved surveillance programme for drug resistance to malaria in Côte d’Ivoire

Control of Strobilurin Fungicides in Wheat Using Direct Analysis in Real Time Accurate Time-of-Flight and Desorption Electrospray Ionization Linear Ion Trap Mass Spectrometry

Ambient mass spectrometry has been used for the analysis of strobilurin residues in wheat. The use of this novel, challenging technique, employing a direct analysis in a real time (DART) ion-source coupled with a time-of-flight mass spectrometer (TOF MS) and a desorption electrospray ionization (DESI) source coupled with a linear ion trap tandem MS (LIT MSn), permitted a direct screen of the occurrence of target fungicides in treated grains in less than 1 min. For quantification purpose by DART-TOF MS, an ethyl acetate extract had to be prepared. With the use of a prochloraz as an internal standard, the performance characteristics obtained by repeated analyses of extract, spiked at 50 ¿g kg¿1 with six strobilurins (azoxystrobin, picoxystrobin, dimoxystrobin, kresoxim-methyl, pyraclostrobin, and trifloxystrobin), were in the following range: recoveries 78¿92%, repeatability (RSD) 8¿15%, linearity (R2) 0.9900¿0.9978. The analysis of wheat with incurred strobilurin residues demonstrated good trueness of data generated by the DART-TOF MS method; the results were in a good agreement with those obtained by the conventional approach, i.e., by the QuEChERS sample handling procedure followed by identification/quantification employing high-performance liquid chromatography coupled with tandem mass spectrometry (LC¿MS/MS). Tandem mass spectrometry using DESI-LIT MSn provided a sufficient number of product ions for confirmation of the identity of azoxystrobin and pyraclostrobin in incurred wheat samples

Lorazepam photofate under photolysis andTiO2-assisted photocatalysis: Identification and evolution profiles of by-products formed during phototreatment of a WWTP effluent

This manuscript reports on the study of Lorazepam (LZP) phototransformation pathways under artificial UV and natural solar irradiation, through photolytic and TiO2-assisted photocatalytic processes. Three experimental set-ups were employed: two lab-scale photoreactors, each provided with an UV lamp (one medium pressure mercury lamp and one blacklight blue lamp), and a pilot-scale Solar Plant with Compound Parabolic Collectors (CPCs). Samples collected along the different phototreatment experiments were analyzed by ultra-high performance liquid chromatography-quadrupole-time-of-flight-mass spectrometry (UHPLC/QqToF-MS). The key assumption of the analytical approach was that related compounds (LZP and its by-products (LBPs)) provide identical "diagnostic fragment ions". Identification was also based on the chlorine atoms specific isotopic pattern, as well as accurate masses. Six major LBPs were identified and elucidated, with nominal [M+H]+ masses of 337, 303, 319, 275, 291 and 293Da. The proposed LZP photodegradation mechanism included the initial opening of the diazepinone seven-membered ring, followed by a rearrangement into a highly stabilized six-membered aromatic ring and subsequent cleavage and/or hydroxylation reactions. The evolution profiles of LBPs were described for each of the three experimental prototypes and the CPCs Solar Pilot Plant proved to be the most efficient one. Finally, LZP photocatalytic degradation was further assessed on a municipal effluent, where the photoproducts generated showed to be more persistent than LZP itself. © 2013 Elsevier Ltd