Relationship between biological parameters and bioaccumulation of some organochlorines (pesticides,PCB) by fishes in the River Seine (France)

The accumulation of organochlorine compounds (α, β and γ HCH, HCB, pp'DDE pp'DDT and polychlorobiphenyls) by fishes of two different species, the Roach (Rutilus rutilus) and the Perch (Perca fluviatilis), predator of the Roach, have been studied at two stations situated on the catchment basin of the Seine. Only polychlorobiphenyls show high contents in these fishes. The polychlorobiphenyl compositions of these organisms correspond to those found in most environments. There is no systematic relationship between the bioconcentration and the size of the fish. The reproductive cycle appears to have a significant impact on the organochlorine contents. Moreover, the extent of PCB amplification with trophic level depends partly on the mode of expression of their contents, related either to body weight or to lipid weight. Thus the PCB body contents in the Perch are slightly higher than in the Roach, whereas, regarding lipid weight, the contents are twice as high as in the predator species. In the Roach, body contents of micropollutants are only two six times higher than in Molluscs (Anodonta cygnea, Vivipara vivipara). The Roach and the zebra mussel show important differences in the PCB composition, whereas there are none between the Perch and the Roach; in the latter species, they do not seem to change with age.     

On the use of tree leaves as bioindicators of the contamination of air by organochlorines in France

The possibility of using leaves from plane trees (Platanus vulgaris S.) as bioindicators of the pollution of air by organochlorines has been studied in Paris, the Paris region and throughout France. Extracts were obtained by mechanical shaking and analyzed by capillary column gas chromatography. Inter- and intraspecific variations in the concentrations of polychlorinated biphenyls are seen to show a factor 3. In these conditions contents throughout France can be considered homogeneous. This type of biomonitoring would then appear to be capable of discerning, on a continental scale, variations of a factor 10 in atmospheric concentrations. Air/leaf bioconcentration factors are around 10⁵ for PCBs and 10⁴ for lindane.     

River bed restoration boosts habitat mosaics and the demography of two rare non-aquatic vertebrates

Many river revitalization projects are currently under development, but we still lack proper assessments of their effects on biodiversity, especially regarding non-aquatic vertebrates. We analysed the progressive changes in habitat mosaics, and the demographic response of two rare species of wading birds along a Swiss section of the Rhone river over a period of three decades. During the period preceding revitalization, the diversity of the habitat mosaic had been steadily declining. This impoverishment could however be reverted after 1994, when the revitalization was initiated: in 2006, the re-established habitat matrix was more diverse than at any time during the previous 27 years. The formerly channelized stream underwent radical transformation as it mutated into a heterogeneous braided river boosting pioneer riverine habitats. This has led the two wading bird species to establish significantly more territories than before the revitalization operations. Population size of Actitis hypoleucos and Charadrius dubius increased by 83% and 20%, respectively, between 1995 and 2007. During the same period, A. hypoleucos declined dramatically in Switzerland as a whole, whilst C. dubius showed no distinct population trend. The response of the two waders may have resulted from an increase in the number of lateral arms of the river, where the availability of productive temporary ponds provides excellent foraging opportunities. A significant proportion of these habitats was created by a targeted extraction of sediments with the objective to promote biodiversity while maintaining economic activity and improving security against floods. This suggests that gravel exploitation is not incompatible with efficient river restoration.     

Interfacial and oil/water emulsions characterization of potato protein isolates

Interfacial and emulsifying properties of potato protein isolate (PPI) have been studied to evaluate its potential application to stabilize oil/water emulsions at two pH values (2 and 8). The amount, type, and solubility of proteins and the size of aggregates have been determined in aqueous dispersion. Air-water and oil-water interfacial properties (adsorption, spreading, and viscoelastic properties) have been determined as a function of concentration and pH using soluble phases of PPI. The behavior of PPI stabilized oil/water emulsions has been then analyzed by droplet size distribution measurements and interfacial concentration. PPI exhibits low solubility over a wide range of pH values, with the presence of submicrometer aggregates. The pH value exerts a negligible effect on interfacial tension (oil-water) or surface pressure (air-water) but displays very important differences in viscoelastic properties of the interfacial films formed between oil and water. In this sense, pH 8 provides a major elastic response at oil-water interfaces as compared to pH 2. In relation with this result, a much higher ability to produce fine and stable emulsions is noticed at pH 8 as compared to pH 2. Consequently, there is an evident relationship between the rheological properties of the oil-water interfacial films and the macroscopic emulsion behavior.     

Presence of Pharmaceuticals and Hormones in Waters from Sewage Treatment Plants

This paper describes the presence of 33 pharmaceuticals and hormones in waters from two sewage treatment plants (STPs) situated in Catalonia, in northeastern Spain. The target compounds were one psychoactive stimulant, one antiepileptic, four analgesics and non-steroidal anti-inflammatories, one lipid regulators, two anti-ulcer agents, nine antibiotics (sulfonamides and macrolides), two beta-blockers, two metabolites, and 11 hormones (free and conjugates). The determination was performed using liquid chromatography coupled to tandem mass spectrometry after enrichment by solid-phase extraction with Oasis HLB sorbent. Most of the pharmaceuticals were found in both influent and effluent samples from the two STPs. The most frequently detected were caffeine, acetaminophen, carbamazepine, diclofenac, ibuprofen, naproxen, sulfamethoxazole, sulfapyridine, sulfathiazole, ranitidine, omeprazole, estrone 3-sulfate, and estradiol 17-glucuronide. Specifically, the highest concentrations found in influents were 19,850?ng/L (acetaminophen), 9,945?ng/L (caffeine), 4,215?ng/L (ibuprofen), 5,695?ng/L (sulfamethoxazole), and 5,140?ng/L (sulfathiazole). Most of the pharmaceuticals present in influent waters were found in effluents at lower concentrations. The highest concentrations in effluents were 970?ng/L (caffeine), 670?ng/L (sulfamethoxazole), 510?ng/L (bezafibrate), and 1,032?ng/L (diclofenac).     

Influence of difloxacin-contaminated manure on microbial community structure and function in soils

Difloxacin (DIF) belongs to the fluoroquinolones, a frequently detected group of antibiotics in the environment. It is excreted in pig manure to a large extent and may consequently reach soils in potentially effective concentrations via manuring. The aim of this study was to assess the effects of DIF-spiked manure on microbial communities and selected functions in soils in a microcosm experiment up to 1 month after application. To test a dose dependency of the effects, three different concentrations of DIF (1, 10 and 100 mg/kg of soil) were used. Microcosms with application of pure manure, as well as untreated microcosms served as control. The addition of pure manure resulted in an increase of microbial biomass and soil respiration as well as a reduced bacteria/fungi ratio. Due to the fast and strong immobilisation of DIF, effects of the antbiotic compound were only visible up to 8 days after application (microbial biomass; respiration; potential denitrification; ratio of bacteria/fungi). As expected these short-term effects resulted in reduced potential denitrification rates as well as a reduced bacteria/fungal ratio in the treatments were DIF has been applied. Surprisingly, microbial biomass values as well as respiration rates were increased by DIF application. Other parameters like nitrate and ammonium content in soil were not influenced by DIF application at any time point. Long-term effects (32 days after application) were only visible for the potential nitrification rates. For those parameters that were influenced by the DIF application a clear dose dependency could not be described.     

<Emphasis Type="Italic">In vitro</Emphasis> morphogenic response of leaf sheath of <Emphasis Type="Italic">Phyllostachys bambusoides</Emphasis>

Nodal segments from secondary branches of saplings of Phyllostachys bambusoides were inoculated in MS medium to assess the in vitro morphogenic response of leaf sheath through the induction to callogenesis by Picloram(4-amino-3,5,6-trichloropicolinic acid) at different concentrations of carbohydrate under the same conditions with presence or absence of luminosity.In our experiment,secondary explants were kept in MS medium containing 8.0 mg·L-1 of Picloram for the callus formation.Calluses were transferred in MS medium supplemented with sucrose,fructose and glucose(control,2%,4% and 6%).Results show that Picloram induced the callogenesis in leaf sheath.The secondary embryogenesis was formed in yellow-globular callus.The sucrose as carbohydrate source in the absence of light was more efficient to induce rhizogenesis.Glucose was more efficiency in the presence of light.Callogenic induction and further embryogenesis evidenced the competence and determination of leaf sheath cells.     

Comparison of the development <Emphasis Type="Italic">in planta</Emphasis> of a pyrrolnitrin-resistant mutant of <Emphasis Type="Italic">Botrytis cinerea</Emphasis> and its sensitive wild-type parent isolate

Botrytis cinerea is able to build-up resistance to pyrrolnitrin, an antibiotic produced by diverse biocontrol agents, possibly compromising the durability of this method of disease control. The development of two near-isogenic lines of B. cinerea differing in their level of resistance to pyrrolnitrin was compared in tomato plants and on PDA medium. In tomato plants, significant differences in the percentage of infected petioles 1 day after inoculation and in symptom progression on petioles and stems were observed between the resistant mutant and the sensitive wild-type parent, suggesting a difference in their level of aggressiveness. Cytohistological investigations revealed that conidia of both near-isogenic lines germinated 6 h after inoculation and mycelium developed within petiole tissues 12 h after inoculation. However, while the wild-type parent isolate spread throughout the petiole and rapidly invaded the stem tissues via the leaf-abscission zone 72 h after inoculation, the pyrrolnitrin-resistant mutant failed to extend beyond petiole tissues to invade the stem. Moreover, 72 h after inoculation, the mycelial development of the pyrrolnitrin-resistant mutant was accompanied by abnormal glycogen accumulation and chlamydospore-like cell formation. In contrast, wild-type parent mycelium was normally structured with intensive colonization of stem tissues. Additionally, on PDA medium the mycelium of the pyrrolnitrin-resistant mutant was less vigorous than the wild-type isolate. These results suggest that the acquisition of pyrrolnitrin-resistance in B. cinerea is accompanied by changes in mycelial structure and reduction in mycelial growth, leading to a noticeable loss of aggressiveness on tomato plants.     

Plasma and urine concentrations of marbofloxacin following single subcutaneous administration to cats

The pharmacokinetic properties of marbofoxacin, a third generation fluoroquinolone, were investigated in 12 healthy adult cats after single subcutaneous (SC) administration of 2 mg/kg BW (Part I, n=8 cats) and 4 mg/kg BW (Part II, n=4 cats). In each part of the study blood and urine samples were collected before treatment and thereafter for 5 days. The plasma and urine concentrations of marbofloxacin were determined by HPLC with UV detection. Pharmacokinetic calculations were performed for each treated animal using an open one-compartment-model with first-order elimination after SC dosing. Marbofloxacin in plasma (means): Maximum concentrations (Cmax) of about 1.2 and 3.0 microg/ml were measured 2.3 and 4 hours (tmax) after dosing of 2 and 4 mg/kg BW, respectively. Elimination from the body was low with a total clearance (Cl/F) of approximately 0.1 l/h/kg for both dosages. The half-life (t 1/2) for this process was calculated with 8-10 hours. AUC increased almost proportional when doubling the dose, i.e., 19.77 +/- 6.25 microg * h/ml (2 mg/kg BW) and 51.26 +/- 11.83 microg * h/ml (4 mg/kg BW). Plasma kinetics measured were in accordance with data from literature. Marbofloxacin in urine (means): Maximum drug concentrations were detected 4 and 8 hours after dosing with 70 microg/ml (2 mg/kg BW) and 160 microg/ml (4 mg/kg BW), respectively. Inhibitory effects of the urinary matrix on the antimicrobial activity of the drug were taken into account when performing PK/PD calculations. However, a concentration-dependent bactericidal activity (Cmax/MIC > 8-10) which is claimed for fluoroquinolones was sufficiently met with focus on Escherichia (E.) coli (MIC90 0.5 microg/ml). In the same matrix a threshold value of 1.0 microg/ml was undercut 82 and 116 hours after SC dosing, respectively. Hence, a time-dependent bacteria killing kinetic (T > MIC) which may be of relevance for some Gram-positive germs like Staphylococcus spp. (MIC90 1.0 microg/ml) should be covered, too.