Tomato Systemin induces resistance against Plectosphaerella cucumerina in Arabidopsis through the induction of phenolic compounds and priming of tryptophan derivatives.

Phytocytokines are endogenous danger peptides that are actively released after a pest or pathogen attack, triggering an amplification of plant immune responses. Here, we found that Systemin, a peptide from tomato, has a substantial impact at the molecular level in Arabidopsis plants that leads to induced resistance against Plectosphaerella cucumerina. Using transcriptional and metabolomics approaches, and loss-of-function mutants to analyse the molecular mechanisms underlying induced resistance against the necrotroph, we decipher the enhanced molecular responses in Systemin-treated plants following infection. Some protein complexes involved in the response to other damage signals, including the BAK1-BIK1 protein complex and heterotrimeric G proteins, as well as MPK activation, were among the early signalling events triggered by Systemin in Arabidopsis upon infection. Non-targeted analysis of the late responses underlying Systemin-Induced Resistance1 (Sys-IR) showed that phenolic and indolic compounds were the most representative groups in the Systemin metabolic fingerprint. Lack of flavonoids resulted in the impairment of Sys-IR. On the other hand, some indolic compounds showed a priming profile and were also essential for functional Sys-IR. Evidence presented here shows that plants can sense heterologous peptides from other species as danger signals driving the participation of common protein cascades activated in the PTI and promoting enhanced resistance against necrotrophic fungus.

Mycorrhizal tomato plants fine tunes the growth-defence balance upon N depleted root environments.

In low nutritive environments, the uptake of N by arbuscular mycorrhizal (AM) fungi may confer competitive advantages for the host. The present study aims to understand how mycorrhizal tomato plants perceive and then prepare for an N depletion in the root environment. Plants colonized by Rhizophagus irregularis displayed improved responses to a lack of N than nonmycorrhizal (NM) plants. These responses were accomplished by a complex metabolic and transcriptional rearrangement that mostly affected the gibberellic acid and jasmonic acid pathways involving DELLA and JAZ1 genes, which were responsive to changes in the C/N imbalance of the plant. N starved mycorrhizal plants showed lower C/N equilibrium in the shoots than starved NM plants and concomitantly a downregulation of the JAZ1 repressor and the increased expression of the DELLA gene, which translated into a more active oxylipin pathway in mycorrhizal plants. In addition, the results support a priorization in AM plants of stress responses over growth. Therefore, these plants were better prepared for an expected stress. Furthermore, most metabolites that were severely reduced in NM plants following the N depletion remained unaltered in starved AM plants compared with those normally fertilized, suggesting that the symbiosis buffered the stress, improving plant development in a stressed environment.

[Maxillary sinus infection by Bacillus licheniformis: a case report from Djibouti]. / Sinusite maxillaire due à Bacillus licheniformis: à propos d'un cas survenu à Djibouti.

Aerobic, spore-forming gram-positive Bacillus spp infections are rare and reported mainly in immunocompromised hosts. We report a case of acute unilateral maxillary sinusitis, caused by Bacillus licheniformis, in a 35-year-old French soldier stationed in Djibouti. It was easily identifiable due to its typical culture and resistance profile. This case is interesting for two reasons: first, it is, to our knowledge, the first case of sinusitis attributed to this microbe, and second, it has rarely been described in immunocompetent patients without altered skin or mucous membranes.

[Mycobacterium simiae pneumonia: a case report]. / Pneumopathie à Mycobacterium simiae: à propos d'un cas.

We report a case of Mycobacterium simiae pneumonia in an immunocompetent women aged 55 years, after a stay in Thailand. The diagnosis was based on culture isolation of non-tuberculous mycobacteria from bronchoalveolar lavage. The culture isolate was identified as M. simiae by biochemical and molecular methods. The patient was treated. Her condition remained stable for 5 years. During the sixth years, a relapse occurred, and a new treatment was prescribed. This is a rare case in view of the absence of any predisposing factor. M. simiae should be considered a possible causative agent of pulmonary disease, even in immunocompetent patients.

Faecal carriage of extended-spectrum ß-lactamase-producing enterobacteria among soldiers at admission in a French military hospital after aeromedical evacuation from overseas.

The aim of this study was to assess the faecal carriage of carbapenemase-producing enterobacteria (CPE) and extended-spectrum ß-lactamase (ESBL)-producing enterobacteria among soldiers at admission in a French military hospital after aeromedical evacuation from overseas. During a period of 1 year, 83 rectal swabs collected in French soldiers at admission were screened for multidrug-resistant enterobacteria with a chromogenic medium. ESBL detection was performed with the double-disc synergy test in the absence or presence of cloxacillin. The genotypic characterisation of resistance mechanisms, sequence typing and phylotyping was performed by polymerase chain reaction (PCR) and sequencing with bacterial DNA extracted from isolates. No CPE was detected. Eleven ESBL Escherichia coli isolates belonging to four phylogenetic groups were detected, including ten CTX-M-15 and one CTX-M-14. The overall gut colonisation with ESBL-producing bacteria (13.25 %) was 6-fold higher than that reported in soldiers in the suburbs of Paris in 2009. ESBL faecal carriage was particularly high (34.48 %) in soldiers repatriated from Afghanistan (risk ratio = 18.62; p = 0.0001). This study highlights the importance of systematic additional contact precautions and CPE/ESBL screening in soldiers repatriated from overseas in French hospitals.

An 8-year survey of strains identified in blood cultures in a clinical haematology unit.

The aim of our study was to determine the epidemiological profile and the antibiotic susceptibility of bacteria and fungi identified from blood cultures in the patients of the clinical haematology unit. A retrospective study was carried out over an 8-year period (2003-2010) in the clinical haematology unit of the Percy Military Medical Center. During this period, we collected 723 isolates: Gram-negative bacilli (70.8%) and Gram-positive cocci (18.7%). The four most commonly isolated species were Escherichia coli (18.5%), Pseudomonas aeruginosa (14.8%), Stenotrophomonas maltophilia (6.2%) and Staphylococcus epidermidis (5.4%). The rate of methicillin-resistant Staphylococcus aureus was 6.45% and that of coagulase-negative staphylococci 61.2%. No resistance to glycopeptides was observed. In E. coli, as in the Klebsiella-Enterobacter-Serratia group, a 27% resistance to fluoroquinolones was observed. Concerning P. aeruginosa, the phenotypes were distributed over penicillinase (23.4%) and cephalosporinase (13.1% were resistant to ceftazidime). The impermeability rate of imipenem was 9.3%. The aggressiveness and duration of haematological treatments explains why infections remain one of the main complications of neutropenia. The emergence of new or unusual bacteria is highly likely. Antibiotic selective pressure and long periods of hospitalization could explain the emergence of multiresistant bacteria. As a consequence, epidemiological surveillance is indispensable.

[Evaluation of a hand hygiene technique in healthcare workers]. / Evaluación de la técnica de higiene de manos en profesionales asistenciales.

OBJECTIVE: To evaluate the quality of hand hygiene in healthcare workers and the influence of wearing jewellery. METHODS: A sample of 293 healthcare professionals of different categories and on different shifts was studied. Hand hygiene was evaluated by a fluorescent agent that allowed us to determine the areas of the hand that had been in contact with the solution. Each hand was divided into 6 zones to quantify the quality of hygiene, the maximum score was 12 points. The wearing of jewellery was quantified. RESULTS: The mean score obtained was 8.3 (SD 2.0) out of 12 points. At least one untreated area of the hand was found in 95.2% of subjects. The results in fingers, thumbs and wrists were significantly lower than those obtained in other areas of the hand (p<.001), being dirty in over 50% of the participants. A dirty wrist was observed in 90% of those who wore a watch and in 92.7% of those wearing a bracelet,and the 84.3% of subjects who wore a ring had dirty fingers. CONCLUSIONS: Healthcare workers did not apply the technique of hand hygiene effectively. Areas where the alcoholic solution did not act as often were: thumbs, fingers and wrist. The use of watches, bracelets and rings prevent good hygiene.