In utero alcohol exposure impairs vessel-associated positioning and differentiation of oligodendrocytes in the developing neocortex.

Prenatal alcohol exposure (PAE) is a major cause of nongenetic mental retardation and can lead to fetal alcohol syndrome (FAS), the most severe manifestation of fetal alcohol spectrum disorder (FASD). FASD infants present behavioral disabilities resulting from neurodevelopmental defects. Both grey and white matter lesions have been characterized and are associated with apoptotic death and/or ectopic migration profiles. In the last decade, it was shown that PAE impairs brain angiogenesis, and the radial organization of cortical microvessels is lost. Concurrently, several studies have reported that tangential migration of oligodendrocyte precursors (OPCs) originating from ganglionic eminences is vascular associated. Because numerous migrating oligodendrocytes enter the developing neocortex, the present study aimed to determine whether migrating OPCs interacted with radial cortical microvessels and whether alcohol-induced vascular impairments were associated with altered positioning and differentiation of cortical oligodendrocytes. Using a 3D morphometric analysis, the results revealed that in both human and mouse cortices, 15 to 40% of Olig2-positive cells were in close association with radial cortical microvessels, respectively. Despite perinatal vascular disorganization, PAE did not modify the vessel association of Olig2-positive cells but impaired their positioning between deep and superficial cortical layers. At the molecular level, PAE markedly but transiently reduced the expression of CNPase and MBP, two differentiation markers of immature and mature oligodendrocytes. In particular, PAE inverted their distribution profiles in cortical layers V and VI and reduced the thickness of the myelin sheath of efferent axons. These perinatal oligo-vascular defects were associated with motor disabilities that persisted in adults. Altogether, the present study provides the first evidence that Olig2-positive cells entering the neocortex are associated with radial microvessels. PAE disorganized the cortical microvasculature and delayed the positioning and differentiation of oligodendrocytes. Although most of these oligovascular defects occurred in perinatal life, the offspring developed long-term motor troubles. Altogether, these data suggest that alcohol-induced oligo-vascular impairments contribute to the neurodevelopmental issues described in FASD.

Behaviour of doxycycline, oxytetracycline, tetracycline and flumequine during manure up-cycling for fertilizer production.

The fate of four widely used veterinary antibiotics (doxycycline, flumequine, oxytetracycline and tetracycline) during manure upcycling was investigated at laboratory and pilot scale. The pilot was operated continuously, while the laboratory scale in batch mode. Both set-ups consisted of anaerobic digestion, ammonia stripping and a solid liquid separation step. A partial nitritation anammox process was used to treat the laboratory scale effluent. In the pilot installation, pig manure as feed, natural occurring antibiotics levels were reduced by 92% for doxycycline, 88% for flumequine, 95% for oxytetracycline and 100% for tetracycline. In the laboratory scale set-up, antibiotic free sludge was used and the four substances were spiked. The input antibiotics concentration was reduced by 85% for doxycycline, 46% for flumequine, 97% for oxytetracycline and 100% for tetracycline. In both set-ups the centrifuge cake was identified as the major emission pathway for residual antibiotics. Manure upcycling, while producing fertilizers, can be considered effective in reducing the residual antibiotic load.

[A sensitive, specific and predictive isolation medium developed for Stenotrophomonas maltophilia study in healthcare settings]. / La mise au point d'un milieu sensible, spécifique et prédictif de recherche de Stenotrophomonas maltophilia dans l'environnement des soins.

BACKGROUND: Stenotrophomonas maltophilia (Smalto) is a prominent nosocomial pathogen, commonly isolated in the hospital environment. Multiple Smalto nosocomial outbreaks have been linked to contaminated water sources. This study aimed to develop a medium able to ease healthcare environment Smalto isolation. METHODS: Financed, from March 2007 to June 2008, by a university hospital of Amiens' clinical research program, this study allowed Stenotrophomonas maltophilia selective medium with coloured indicator (SM2i) development. SM2i is constituted of Mueller Hinton agar (MH), maltose, DL-methionine, bromothymol blue. The mixture sterilized is refreshed at 50 degrees C, its pH adjusted to 7.1, and render selective by addition of vancomycin, imipenem and amphotericin B. Then, SM2i agar is sunk into 90 cm diameter Petri dish dated and stored at 4 degrees C for 4 weeks. SM2i is developed using Pasteur Institute culture type collection (CIP) strains of Smalto, Burkholderia cepacia, Pseudomonas aeruginosa (Psa) and a Smalto strain of our hygiene laboratory collection. It was validate on Psa imipenem-resistant and Enterococcus faecium vancomycin-resistant strains, then, tested on cold water first jet and faucet cotton-swabs samples. SM2i tests were made in comparison with the MH agar, MH agar plus four paper disks loaded 10 microg of imipenem and Cetrimed agar. Its sensitivity, specificity, positive (PPV) and negative (NPV) predictive values, accuracy, likehood-ratio (LR) and Youden index have been determined. RESULTS: SM2i agar is better in culturing Smalto test-strains. On SM2i, Smalto colonies are smooth, round, greeny, olive or lime green, have a green olive centre with a peripheral lighter or a dark green centre with an olive green suburb surrounded by a blue halo. SM2i is a selective, specific, predictive, accurate medium to search for Smalto in healthcare environment. In 122 pairs of cold water first jet and taps cotton-swabs samples, Smalto was isolated from 14.8% of water samples, 10.7% of cotton-swabs samples. It was isolated alone in 6.6% of water samples and 2.5% of swab samples. Thus, smalto has biocontaminated 17.2% of cold water taps. Compared to MH agar, SM2i sensitivity, specificity, PPV, NPV, accuracy, LR were 100, 100, 100, 100, 100% and infinity, and 87.5, 100, 100, 98.1, 98.4% and infinity for water and cotton-swabs samples respectively. CONCLUSION: SM2i is a selective, specific, predictive medium which can allow easily isolating and identifying accurately Smalto in environmental samples. Its evaluation on clinical samples is on going.

[Stenotrophomonas maltophilia and Pseudomonas aeruginosa water-associated microbiologic risk assessment in Amiens' University Hospital Centre]. / Evaluation des risques microbiologiques hydriques associés à Stenotrophomonas maltophilia et Pseudomonas aeruginosa au CHU d'Amiens.

BACKGROUND: Pseudomonas aeruginosa (Psa) and Stenotrophomonas maltophilia (Smalto) are major opportunistic waterborne pathogens causing hospital-acquired infections. This study aimed to assess the biocontamination level of cold water used in Amiens' university hospital wards, from March to June 2008. METHODS: We cultivated 122 pairs of cold water first jet and taps cotton-swabs on Cetrimide agar for Psa, on Stenotrophomonas maltophilia selective medium with coloured indicator (SM2i) for Smalto, on Mueller Hinton agar used as isolation medium reference for both, 48h at 30 degrees C. Data analysed with Epi-Info 6.04dFr were compared with chi(2) test, significant at p<.05. RESULTS: Psa and Smalto were isolated in 26.2 and 14.8% of water samples and in 21.3 and 10.7% of swab samples respectively. They were associated in 11.5% of water samples and 5% of swab samples. Psa was alone in 13.1% of water samples and 7.4% of swab samples whereas Smalto was found in 6.6% of water and 2.5% of swabs. Psa and Smalto were isolated from 14.8% of water samples and 8.2% of swab samples of the same tap. Finally, respectively 35.2 and 17.2% of the cold water taps were biocontaminated by Psa and Smalto. In fact, microbiologic water taps contamination risk was two-fold higher for Psa than for Smalto, p<.001, without variation between wards. CONCLUSION: Sm2i and Cetrimide are suited and efficient medium respectively for Smalto and Psa isolation. Cold-water samples are sufficient for waterborne pathogens biocontamination risk appraisal. Our results urged healthcare workers on efficient water fittings microbiologic risk control to prevent healthcare associated waterborne infections, notably due to Psa and Smalto.

A three-pronged attack against AIDS infection in the lab.

Education, protective supplies, and a formal policy of precautions against blood-borne infection eased employee fears of AIDS.

Comparison of four extraction methods for the analysis of 24 pesticides in soil samples with gas chromatography-mass spectrometry and liquid chromatography-ion trap-mass spectrometry.

With a view to analyse multiresidues of pesticides in soil samples, a new ultrasonic solvent extraction (USE) was compared to the European Norm DIN 12393 for foodstuff (extraction with acetone, partitioning with ethylacetate/cyclohexane and clean-up with gel permeation chromatography (GPC)), the QuECheRS method and a pressurised liquid extraction (PLE) method. Pesticides were analysed with both GC-MS and HPLC-MS/MS. The reference materials were the EUROSOIL 7 and its subsoil SO26 as well as a sea sand. All the substances were observed to be linear in the range of 4-800 ng g(-1) for the European Norm DIN 12393, 7-1400 ng g(-1) for the USE method and 20-4000 ng g(-1) for the QueCheRS and the PLE methods. Limits of detection (LOD) and limits of quantification (LOQ) were with HPLC between 0.006 and 0.23 ng g(-1) and between 0.022 and 0.77 ng g(-1), respectively, with the exception of diuron (LOD up to 11.8 ng g(-1); LOQ up to 39.2 ng g(-1)). With GC they ranged from 3.0 to 87.5 ng g(-1) and from 10 to 292 ng g(-1), respectively. All substances could be recovered with USE as well as with the QuECheRS method; the European Norm DIN 12393 could not recover carbendazim and metamitron; the PLE carbendazim, metamitron and monolinuron. For the remaining substances, recoveries at a 500 ng g(-1) fortification level ranged from 10.9 to 96.3% with the USE. In comparison, the QuECheRS method was the most efficient extraction method with recoveries from 27.3 to 120.9%. It was followed by the European Norm DIN 12393 with recoveries between 6.8 and 108.1% and the PLE with recoveries from 12.2 to 153.2%. Recoveries were higher from the EUROSOIL 7 than from the SO 26. The repeatability expressed in term of standard deviation was below 20% for all substances and all materials.

Pesticide and non-dioxin-like polychlorinated biphenyls (NDL-PCBs) residues in foodstuffs from Ismailia city, Egypt.

Samples of vegetables and cereals from Egypt were screened for 113 pesticides, of which 68 were quantified, using gas chromatography-mass spectrometry (GC/MS) with limits of detection (LODs) ranging from 0.02 to 1.9 µg kg⁻¹. In addition, the residues of 17 non-dioxin-like polychlorinated biphenyls (NDL-PCBs) were measured in samples of animal origin (meat, dairy products and seafood) using high-resolution gas chromatography (HRGC)/high-resolution mass spectroscopy (HRMS). None of the cereal samples and 72.7% of the vegetables contained any detectable levels of the pesticides. Detectable residues, not exceeding the current European Union maximum residue limits (MRLs) were found in 27.3% of vegetables. The estimated daily intake for detected pesticides was well below their corresponding acceptable daily intake (ADI), with exposure ranges between 0.002% of the ADI for profenofos and 0.2% of the ADI for lambda-cyhalothrin. The sum concentration of 17 PCBs congeners varied between 2.5 and 322 ng g⁻¹ fat, corresponding to 1.7-216 ng g⁻¹ fat for the seven indicator PCBs. The highest values were measured in seafood, the lowest in dairy products. Hexa-CB 153, 138 and hepta-CB180 were the congeners with the highest contribution. PCBs congener profiles found in most of the samples were consistent with the expected profile for Aroclor 1260 and 1262. PCBs' contamination levels reported in this paper were many times lower than in developed countries, except for chicken samples. Also, the dietary intake of seven indicator PCBs due to the consumption of food of animal origin (4.84 ng kg⁻¹ body weight day⁻¹) from Ismailia city, Egypt, is several times lower than the intake in European Union countries.