The use of reclaimed water to irrigate agricultural crops has increased in recent years as a consequence of water shortage constituting a potential risk for human health. The main objective of this ...study was to evaluate the impact on the soil-plant system and determining the accumulation of carbamazepine (CBZ), diclofenac (DCF), ketoprofen (KTP) and naproxen (NPX) in the edible part of lettuce under commonly used agricultural practices in commercial production. For this purpose, red oak baby lettuce (Lactuca sativa L.) was irrigated with reclaimed water fortified with different concentrations of pharmaceuticals. The study was carried out in two different scenarios: soil and tray. The tray experiments were conducted with substrate and took place at three different seasons of the year. Lettuce tissue sampled from these experiments were analysed 3 times during the lettuce growing cycle (first, second and third harvest). The practices of first harvest regrowth were also evaluated. For all experiments, CBZ showed the highest accumulation in lettuce leaves of the pharmaceuticals tested, showing a correlation between irrigation exposure time and pharmaceutical uptake. Unexpectedly, DCF was the compound with the highest uptake levels after regrowth practices. Results suggested that pharmaceuticals uptake could be directly associated with the irrigation method and possible accumulation in soil and substrates, while concentration of pharmaceuticals in substrates were 10 times higher. Based on the concentration values detected in lettuce leaves, the risk assessment suggests that no compounds imply any risk to human health, except CBZ for those on vegetarian diets in the tray scenario. Although commercial agricultural practices are usually not considered with regards to risk reduction, in this experiment we demonstrated that climatic conditions are a key factor in pharmaceuticals uptake and different agricultural practices (soil cropping and drip irrigation) can limit the presence of pharmaceutical compounds in crops.
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•A correlation between irrigation exposure time and pharmaceutical uptake.•The uptake of pharmaceuticals is directly associated with the irrigation method and the possible accumulation in soils and substrates.•The pharmaceutical concentration in substrate were 10 times higher than in soil.•The consumption of lettuce grown in trays may pose a health risk regarding carbamazepine for vegetarians.•Climatic conditions and different agricultural practices are a key factor in pharmaceuticals uptake.
Although previous studies have reported Leptospira carriage in kidneys and urine of cats, the role of these animals in leptospirosis epidemiology remains poorly understood. Using molecular methods, ...we investigated Leptospira renal carriage in 172 feral cats from Reunion Island, an oceanic geographically isolated island located in the South West Indian Ocean. Only one out of the 172 analysed specimens tested positive for Leptospira DNA through quantitative real-time polymerase chain reaction. Using this positive sample, we could obtain sequences at three Leptospira loci (rrs2, lipL32 and lipL41) allowing to report for the first time Leptospira borgpetersenii naturally infecting cats. Comparisons with bacterial sequences from both acute human cases and animal reservoirs revealed similarities with Leptospira sequences previously reported on Reunion Island. However, the low prevalence (0.6%) reported herein does not support any major role of feral cats in leptospirosis epidemiology on Reunion Island, contrasting with results recently reported on another Indian Ocean Island, Christmas Island. The significance of these discrepancies is discussed.
We report herein the investigation of a leptospirosis outbreak occurring in triathlon competitors on Réunion Island, Indian Ocean. All participants were contacted by phone or email and answered a ...questionnaire. Detection and molecular characterization of pathogenic Leptospira was conducted in inpatients and in rodents trapped at the vicinity of the event. Of the 160 athletes competing, 101 (63·1%) agreed to participate in the study. Leptospirosis was biologically confirmed for 9/10 suspected cases either by real-time PCR or serological tests (MAT or ELISA). The total attack rate, children's attack rate, swimmers’ attack rate, and the attack rate in adult swimmers were respectively estimated at 8·1% 95% confidence interval (CI) 4·3–14·7, 0%, 12·7% (95% CI 6·8–22·4) and 23·1% (95% CI 12·6–33·8). Leptospirosis cases reported significantly more wounds risk ratio (RR) 4·5, 95% CI 1·6–13, wore complete neoprene suits less often (RR 4·3, 95% CI 1·3–14·5) and were most frequently unlicensed (RR 6·6, 95% CI 2·9–14·8). The epidemiological investigation supported that some measures such as the use of neoprene suits proved efficient in protecting swimmers against infection. PCR detection in rats revealed high Leptospira infection rates. Partial sequencing of the 16S gene and serology on both human and animal samples strongly suggests that rats were the main contaminators and were likely at the origin of the infection in humans.
A severe Chikungunya (CHIK) outbreak recently hit several countries of the Indian Ocean. On La Réunion Island, Aedes albopictus was incriminated as the major vector. This mosquito species is ...naturally co‐infected with two distinct strains of the endosymbiont Wolbachia, namely wAlbA and wAlbB, which are increasingly attracting interest as potential tools for vector control. A PCR quantitative assay was developed to investigate Wolbachia/mosquito host interactions. We show that Wolbachia densities are slightly decreased in CHIK virus (CHIKV)‐infected females. We measured the impact of CHIKV replication on a lysogenic virus: WO bacteriophage. Our data indicate that WO is sheltered by wAlbB, likely at a single copy per bacteria, and that CHIKV replication is not a physiological stress triggering WO entrance into the lytic cycle.
A quorum-sensing mechanism involving the pheromone ComX and the ComP-ComA two-component system controls natural competence in Bacillus subtilis. ComX is expressed as a cytoplasmic inactive precursor ...that is released into the extracellular medium as a cleaved, modified decapeptide. This process requires the product of comQ. In the presence of ComX, the membrane-localized ComP histidine kinase activates the response regulator ComA. We compared the sequences of the quorum-sensing genes from four closely related bacilli, and we report extensive genetic polymorphism extending through comQ, comX, and the 5' two-thirds of comP. This part of ComP encodes the membrane-localized and linker domains of the sensor protein. We also determined the sequences of the comX genes of four additional wild-type bacilli and tested the in vivo activities of all eight pheromones on isogenic strains containing four different ComP receptor proteins. A striking pattern of specificity was discovered, providing strong evidence that the pheromone contacts ComP directly. Furthermore, we show that coexpression of comQ and comX in Escherichia coli leads to the production of active pheromone in the medium, demonstrating that comQ is the only dedicated protein required for the processing, modification, and release of active competence pheromone. Some of the implications of these findings for the evolution and the mechanism of the quorum-sensing system are discussed.
Almond trees (Prunus amygdalus L. 'Marta') were subjected to 4 irrigation treatments: I) full irrigation at 110% of ETc (FI) II) partial rootzone drying at 50% of ETc, periodically supplied to only ...one side of the root system, (PRD); III) regulated deficit irrigation at 100% of ETc until June and at 30% of ETc from June until harvest (RDI); IV) rain fed (NI). In August 2007, almonds were harvested, hulled, dried and stored in shell at room temperature for 9 months. Yield average (per ha) was recorded. At harvest, kernel and nut dimensions and weight were determined. Initially and after 2, 5 and 9 months of storage peel color, rupture force, sensorial analysis and oil content (on the kernels), acidity, peroxide value and tocopherols content (on the oil), and antioxidant activity, total phenols and sugar composition (on the defatted powder) were carried out. Yield resulted significantly lower for NI trees than for FI trees, while RDI and PRD trees showed intermediate values. NI kernels and nuts had the lowest weight and size. NI kernels showed a different peel color from the other treatments, while rupture force decreased during storage regardless of irrigation. NI kernels had higher total sugar and sucrose content, with no difference among other treatments. FI, PRD and RDI samples did not show difference in antioxidant activity during storage, while NI showed a statistically lower value than PRD, the highest decrease rate in phenols content, and also received the lowest sensorial evaluation for appearance. Oil acidity and peroxide values increased during storage, regardless of irrigation. Oil from NI samples had higher α-tocopherol content than RDI and FI, after 5 months of storage. In conclusion, PRD and RDI did not significantly affect the yield and produced almonds similar in quality to those obtained by FI, reducing the use of water.
Objectives
The present study, which is part of the ISRCTN16968287 clinical assay, is aimed at determining the effects of cranberry syrup or trimethoprim treatment for UTI.
Methods
This Phase III ...randomised clinical trial was conducted at the San Cecilio Clinical Hospital (Granada, Spain) with a study population of 192 patients, aged between 1 month and 13 years. Criteria for inclusion were a background of recurrent UTI, associated or otherwise with vesico-ureteral reflux of any degree, or renal pelvic dilatation associated with urinary infection. Each child was randomly given 0.2 mL/Kg/day of either cranberry syrup or trimethoprim (8 mg/mL). The primary and secondary objectives, respectively, were to determine the risk of UTI and the levels of phenolic acids in urine associated with each intervention.
Results
With respect to UTI, the cranberry treatment was non-inferior to trimethoprim. Increased urinary excretion of ferulic acid was associated with a greater risk of UTI developing in infants aged under 1 year (RR 1.06; CI 95% 1.024–1.1; P = 0.001).
Conclusions
The results obtained show the excretion of ferulic acid is higher in infants aged under 1 year, giving rise to an increased risk of UTI, for both treatment options.
Genetic competence in both
Bacillus subtilis and
Streptococcus pneumoniae, as well as virulence in
Staphylococcus aureus, are regulated by quorum-sensing mechanisms that use two-component signal ...transduction systems to respond to extracellular peptide pheromones. Recent data indicate that in all three systems closely related strains express markedly different pheromones and polytopic membrane receptor proteins. This polymorphism may function as a sexual isolation mechanims. In
B. subtilis the downstream segment of the competence regulatory pathway acts by controlling the stability of a key transcription factor. In
S. pneumoniae the downstream segment involves the transcriptional activation of a minor sigma factor that is in turn responsible for the expression of late competence genes.
Les rickettsioses des groupes typhus (GT) et boutonneux (GB) sont des zoonoses responsables de 10 à 20 % des fièvres inexpliquées en milieu tropical. Leur mortalité est de 2 à 5 %. Dans notre région, ...aucun cas de fièvre boutonneuse n’a été rapporté malgré l’identification de certains de leurs agents (R. africae, R. felis) dans des vecteurs parasites du bétail, de rongeurs ou d’oiseaux marins (puces et tiques). À contrario, une cinquantaine de cas autochtones de typhus murin a été rapportée depuis la découverte d’un premier cas index en 2011. Dans ce contexte, nos objectifs étaient d’estimer la séroprévalence des rickettsioses du GT et du GB dans notre population, de rechercher des arguments en faveur de leur émergence ou de leur endémicité et d’en identifier les facteurs de risque.
Une étude transversale de séroprévalence a été menée à partir de 241 sérums représentatifs de la population, collectés en 2009 dans le cadre de l’étude CoPanFlu, soit deux ans avant le diagnostic du cas index. Les données sociodémographiques et la localisation du domicile selon le découpage administratif en microrégions (nord, sud, ouest, est) ont été utilisées pour rechercher une agrégation géographique des cas. La détection des IgG anti-rickettsia a été réalisée par immunofluorescence en utilisant des antigènes de R. typhi (GT) et de R. rickettsii (GB). Un titre supérieur ou égal à 1/64 a été considéré comme marqueur d’une infection ancienne.
La prévalence est de 16,2 % (n=39) pour les IgG anti-R. typhi ; de 18,7 % (n=45) pour les IgG anti-R. rickettsii et 12,4 % (n=30) des sérums présentent des IgG dirigées contre les deux antigènes. Dans un modèle ajusté sur le sexe et la microrégion, la proportion de sujets séropositifs pour les IgG anti-R. rickettsii est significativement plus élevée à partir de l’âge de 20 ans : 18,8 % (n=13) pour les 20–39 ans, 21,9 % (n=23) pour les 49–59 ans et 22,0 % (n=9) pour les 60 ans et plus, alors qu’elle est de 0 % pour les 0–19 ans. La proportion des IgG anti-R. typhi n’est pas significativement différente selon les classes d’âge. Fait important, la localisation du domicile dans la microrégion ouest est associée à la séropositivité quel que soit le sérogroupe.
Nos résultats suggèrent que la population a été exposée au typhus murin ainsi qu’à des rickettsioses du GB avant l’identification du cas index. La concentration des exposés dans l’ouest est en accord avec l’incidence décrite chez les malades et avec la distribution des vecteurs. Une étude sérologique complémentaire (adsorption croisée, Western blot) sur un échantillon plus large serait nécessaire pour confirmer ces résultats.
Summary
The Rok (YkuW) protein acts as a negative regulator of comK, which encodes
the competence transcription factor of Bacillus subtilis. In the absence of
Rok, ComK is overproduced, and when ...excess Rok is present comK transcription
is inhibited. Rok acts transcriptionally to repress comK expression but does
not affect ComK stability, which is controlled by the MecA switch. Gel‐shift assays
show that Rok binds directly to a DNA fragment that contains the comK promoter.
SinR and AbrB act negatively on rok transcription, and the inactivation of
rok bypasses the positive requirements for sinR and abrB for
the expression of comK. Therefore, the dependence of comK expression
on SinR and AbrB may be a result of their repression of rok transcription.
It has also been shown in vivo that Rok and ComK can indivi‐dually repress
rok transcription, and that Rok and ComK bind to the rok promoter in
vitro. These interactions establish feedback loops, and the roles of these circuits are discussed.
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