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Background: Pathobionts, bacteria that are typically human commensals but can cause disease, contribute significantly to antimicrobial resistance. Staphylococcus epidermidis is a prototypical pathobiont as it is a ubiquitous human commensal but also a leading cause of healthcare-associated bacteremia. We sought to determine the etiology of a recent increase in invasive S. epidermidis isolates resistant to linezolid., Methods: Whole-genome sequencing (WGS) was performed on 176 S. epidermidis bloodstream isolates collected at the MD Anderson Cancer Center in Houston, Texas, between 2013 and 2016. Molecular relationships were assessed via complementary phylogenomic approaches. Abundance of the linezolid resistance determinant cfr was determined in stool samples via reverse-transcription quantitative polymerase chain reaction., Results: Thirty-nine of the 176 strains were linezolid resistant (22%). Thirty-one of the 39 linezolid-resistant S. epidermidis infections were caused by a particular clone resistant to multiple antimicrobials that spread among leukemia patients and carried cfr on a 49-kb plasmid (herein called pMB151a). The 6 kb of pMB151a surrounding the cfr gene was nearly 100% identical to a cfr-containing plasmid isolated from livestock-associated staphylococci in China. Analysis of serial stool samples from leukemia patients revealed progressive staphylococcal domination of the intestinal microflora and an increase in cfr abundance following linezolid use., Conclusions: The combination of linezolid use plus transmission of a multidrug-resistant clone drove expansion of invasive, linezolid-resistant S. epidermidis. Our results lend support to the notion that a combination of antibiotic stewardship plus infection control measures may help to control the spread of a multidrug-resistant pathobiont.

Study of depression in North-Africa and Sub-Saharan Africa has shown that, since the seventies, the clinical expression of depression is markedly different from that of depression in the West. Several authors have noted the rareness of guilt themes and the frequency of persecution themes and somatic complaints in depressed Africans, even those living in the West. More recent studies have shown an evolution in depressive symptoms in North-Africa with an increase in guilt and a decrease in persecution and somatic complaints. This shift in symptoms brings the expression of depression closer to that observed in the West. Our study addresses delusional depression: in 73 cases of delusional depression, delusions of guilt were present in 31% of cases, persecution in 48% and hallucinations in 31.5%. A comparison of the sub-groups consulting in 1991 and a second sub-group consulting in 1998 shows a marked increase in guilt (23.5 versus 39%).

In recent years research on the neuronal substrate for mental disorders has considerably developed thanks to new brain imaging methods. Functional brain imaging has attracted several workers in their investigations of psychiatric diseases. Some authors have addressed the position of imaging in the diagnosis and, above all, prognosis of acute psychotic disorders. In the following paper, the authors review the published results. Both structural and functional imaging confirm the hypothesis of a neurophysiological contribution to acute psychotic disorders, as shown by ventricular dilatation and functional abnormalities. Nonetheless, imaging does not seem to have a precise and absolute diagnostic and prognostic value, although of undeniable heuristic interest.

Since the discovery of the neuroleptics in 1952, french psychiatrists have proposed a classification of neuroleptics taking into account the pharmalogical and therapeutic differences between these drugs. They distinguished three different clinical effects of neuroleptics: sedative effects, effects on the positive symptoms of schizophrenia and effects on the negative symptoms. However these agents have many side effects including the extrapyramidal syndrome (EPS), akathisia, dystonia and parkinsonism. These side effects occur in up to 75% of patients receiving typical neuroleptics and are the main cause of non-compliance. Since the eighties, clozapine was introduced for use in refractory patients because it has a better efficacy (than haloperidol) specifically on negative symptoms, a better tolerance and fewer effects. After clozapine, several new antipsychotic agents are now available, such as risperidone, olanzapine, sertindole, quietapine, ziprasidone ... Their therapeutical effects are probably linked with a dual antagonist effect on 5HT2 and D2 receptors. The present article reviews the evolution of the use of these new agents, their real efficacy, their adverse effects and their expanding indications. Future research will more clearly establish appropriate treatment guidelines for their use. These new antipsychotics should add a positive modification in schizophrenia care and in some mood disorders. The approach consisting on individualizing dimensions and clusters analysis might be useful to test the efficiency of each antipsychotic on a syndromic dimension.