Soins palliatifs à domicile (formation des médecins généralistes et coordination avec les réseaux de soins palliatifs)

Résumé françaisDIJON-BU Médecine Pharmacie (212312103) / SudocSudocFranceF

Profil clinique et sociodémographique de 168 salariés adressés pour souffrance mentale au travail en consultation psychiatrique de pathologie professionnelle au CHU d'Angers

ANGERS-BU Médecine-Pharmacie (490072105) / SudocSudocFranceF

Multiple independent transmission cycles of a tick-borne pathogen within a local host community

Many pathogens are maintained by multiple host species and involve multiple strains with potentially different phenotypic characteristics. Disentangling transmission patterns in such systems is often challenging, yet investigating how different host species contribute to transmission is crucial to properly assess and manage disease risk. We aim to reveal transmission cycles of bacteria within the Borrelia burgdorferi species complex, which include Lyme disease agents. We characterized Borrelia genotypes found in 488 infected Ixodes ricinus nymphs collected in the Sénart Forest located near Paris (France). These genotypes were compared to those observed in three sympatric species of small mammals and network analyses reveal four independent transmission cycles. Statistical modelling shows that two cycles involving chipmunks, an introduced species, and non-sampled host species such as birds, are responsible for the majority of tick infections. In contrast, the cycle involving native bank voles only accounts for a small proportion of infected ticks. Genotypes associated with the two primary transmission cycles were isolated from Lyme disease patients, confirming the epidemiological threat posed by these strains. Our work demonstrates that combining high-throughput sequence typing with networks tools and statistical modeling is a promising approach for characterizing transmission cycles of multi-host pathogens in complex ecological settings

Impact des mycotoxines en concentration limitée sur la lignée germinale du poulet

National audienc

Impact des principales fusariotoxines, seules ou en association, sur les fonctions testiculaires du poulet de chair

Mycotoxins are secondary metabolites produced by molds. The presence of these contaminants in animal feed isa major problem because mycotoxins have various adverse effects on health, affecting in particular certainfunctions such as reproduction. The objective of our approach is to evaluate the impact of the main fusariotoxins,in vivo and in vitro, on the testicular functions of broiler chickens. For the in vivo test, 5 groups of 12 broilers(Ross PM3) received the control or experimentally contaminated diet from hatch to slaughter (35 days of age).The diets were contaminated in: deoxynivalenol (DON, 5 mg / kg), fumonisins (FBs, 20 mg / kg), zearalenone(ZEA, 0.5 mg / kg) in single contamination or containing the 3 mycotoxins. The mycotoxins required for theexperiments were obtained by culturing toxigenic fungal strains.Analysis of the testis growth and histological examination has shown that the proliferative activity of the testis isincreased in animals exposed to FBs compared to the control group. On the other hand, no difference was foundin markers of cell death (caspase 3 activity and TUNEL immunostaining), of inflammation (IL6, IL1β andIFNɣ), or in oxidative stress (antioxidant capacity and catalase activity). In vitro experiments using purifiedmycotoxins diluted in a solvent (DMSO) were tested on chicken testicular cell cultures after 96 h of exposure.The results confirmed the in vivo data showed no effect at low dose. However, high doses (FB1: 100 nM, ZEA:30 μM, DON 1 μM) have an impact on cell viability.In conclusion, in vitro, only high doses can lead to testicular lesions but in vivo the maximum concentrationsacceptable did not induce any significant effect on the testes of 35 days-old chicken.Les mycotoxines sont des métabolites secondaires produits par certaines moisissures. La présence de cescontaminants dans les aliments destinés aux animaux est un problème majeur, car les mycotoxines peuvent avoir des effets néfastes variés sur leur santé, en impactant notamment certaines fonctions telle que la reproduction. L’objectif de notre démarche est d’évaluer l’impact des principales fusariotoxines, in vivo et in vitro sur les fonctions testiculaires du poulet de chair. Pour l’essai in vivo, 5 groupes de 12 poulets de chair (Ross PM3) ont reçu de la naissance à l’abattage (35 jours d’âge) les aliments suivants : un aliment témoin sain ou un des 4 aliments expérimentalement contaminés avec du déoxynivalénol (DON, 5mg/kg), des fumonisines (FBs, 20 mg/kg), de la zéaralénone (ZEA, 0,5 mg/kg) en contamination unique ou contenant les 3 mycotoxines. Les mycotoxines nécessaires aux expérimentations ont été obtenues par culture de souches fongiques toxinogènes. L’analyse de la croissance et l’examen histologique du testicule ont montré que l’activité proliférative du testicule, est augmentée chez les animaux exposés aux FBs, en comparaison du groupe témoin. Par contre, aucune différence sur les marqueurs de mortalité cellulaire (activité caspase 3 et immunomarquage TUNEL), d’inflammation (IL6, IL1β et IFNɣ), ou de stress oxydatif (capacité antioxydante et activité de la catalase) n’a été révélée entre les lots. Des mycotoxines purifiées et diluées dans un solvant (DMSO) ont été testés sur des cultures testiculaires de poulets après 96h d’exposition. Les résultats ont confirmé les données in vivo montrant aucun effet à faible dose et un effet négatif des doses élevées (FB1: 100 nM ; ZEA : 30 μM, DON 1μM). En conclusion, in vitro, seules des fortes doses peuvent conduire à des lésions testiculaires mais in vivo les doses maximales autorisées n’induisent pas d’effet négatif notable sur les testicules de poulets élevés jusqu’à 35j

Carbon Monoxide Oxidation Promoted by a Highly Active Strained PdO Layer at the Surface of Au 30 Pd 70 (110)

International audienceThe evolution of the Au30Pd70(110) surface was studied by coupling grazing incidence X-ray diffraction and mass spectrometry under oxygen-rich conditions at moderate temperatures (300 to 470 K). This allows us to correlate the depth profile of its structure to its catalytic properties for carbon monoxide (CO) oxidation. Under increasing pressure from ultrahigh vacuum up to 100 mbar, both oxygen and CO induce Pd segregation, even at room temperature. However, in pure oxygen the surface is reorganized with a (1 × 2) missing row reconstruction, whereas in pure CO it is strongly roughened. When oxygen pressure is increased a phase corresponding to the initial step of the oxidation with oxygen dissolution in the subsurface region appears at first. Then, from about 400 K onward, an oxidized thin Pd layer (≤1 nm) is formed growing in the [100]PdO direction. This PdO phase is strained and does not coincide with the P42/mmc structure usually observed for this oxide under ambient conditions. It is more probably consistent with the high pressure I4/mmm PdO structure strained by epitaxy on the underneath alloy. For higher oxidizing conditions and layer thickness, the oxide will then relax to the usual PdO structure. This strained oxide is easily reduced by CO and exhibits a very high activity for CO oxidation. Its catalytic performance at 470 K is comparable to the one found on surfaces of pure palladium at higher temperatures. Furthermore, on the clean Au30Pd70(110) surface, surface oxidation is hindered up to 470 K if CO is introduced prior to oxygen. This indicates that when Pd is alloyed with gold, its binding with CO is stronger than with oxygen. The weakening of the Pd–O binding by surrounding gold atoms is the key of the formation of a well-ordered and very active thin PdO film on Au30Pd70(110)

Oxygen-Induced Changes of the Au 30 Pd 70 (110) Surface Structure and Composition under Increasing O 2 Pressure

SSCI-VIDE+ATARI+MAA:EEHInternational audienc

On Surface Oxidation Issues Arising during CO Oxidation on a PdAu(110) Surface. An In Situ Study by Complementary Environmental Methods (STM, SXRD, XPS)

International audienc

Host specificity, pathogen exposure, and superinfections impact the distribution of Anaplasma phagocytophilum genotypes in ticks, roe deer, and livestock in a fragmented agricultural landscape

In Press, Accepted ManuscriptHost specificity, pathogen exposure, and superinfections impact the distribution of [i] Anaplasma phagocytophilum[/i] genotypes in ticks, roe deer, and livestock in a fragmented agricultural landscap

Covalent binding of antitumor benzoacronycines to double-stranded DNA induces helix opening and the formation of single-stranded DNA: Unique consequences of a novel DNA-bonding mechanism

The majority of DNA-binding small molecules known thus far stabilize duplex DNA against heat denaturation. A high, drug-induced increase in the melting temperature (T-m) of DNA is generally viewed as a good criterion to select DNA ligands and is a common feature of several anticancer drugs such as intercalators (e.g., anthracyclines) and alkylators (e.g., ecteinascidin 743). The reverse situation (destabilization of DNA to facilitate its denaturation) may be an attractive option for the identification of therapeutic agents acting on the DNA structure. We have identified the tumor-active benzoacronycine derivative S23906-1 [(+/-)-cis-1, 2-diacetoxy-6-methoxy-3,3,14-trimethyl 1,2,3,14-tetrahydro-7H-benzo[b]pyrano[3,2]acridin-7- one] as a potent DNA alkylating agent endowed with a helicase-like activity. Using complementary molecular approaches, we show that covalent binding to DNA of the diacetate compound S23906-1 and its monoacetate analogue S28687-1 induces a marked destabilization of the double helix with the formation of alkylated ssDNA. The DNA-bonding properties and effects on DNA structure of a series of benzoacronycine derivatives, including the dicarbamate analogue S29385-1, were studied using complementary biochemical (electromobility shift assay, nuclease S1 mapping) and spectroscopic (fluorescence and T-m measurements) approaches. Alkylation of guanines in DNA by S28687-1 leads to a local denaturation of DNA, which becomes susceptible to cleavage by nuclease S1 and significantly decreases the T-m of DNA. The drug also directly alkylates single-strand DNA, but mass spectrometry experiments indicate that guanines in duplexes are largely preferred over single-stranded structures. This molecular study expands the repertoire of DNA-binding mechanisms and provides a new dimension for DNA recognition by small molecules