Multiplex microarray PCR Unyvero BCU system to accelerate relevant antimicrobial treatment in polymicrobial bloodstream infection.

PURPOSE: To evaluate the performance of a rapid multiplex microarray-based method (Unyvero BCU system, BCU) to identify microorganisms and detect antimicrobial resistance directly from positive blood culture (BC) bottles with polymicrobial growth, and to assess relevance of information provided for timely guidance of polymicrobial bloodstream infection treatment. METHODS: Accuracy, time-to-actionable results and potential impact of BCU on antimicrobial treatment were compared with those of standard of care during a prospective study for the sample analysis (November 2017-November 2018) and a retrospective study for the clinical data analysis and the time-to-result analysis. The study was complemented with an experimental study, based on spiked blood cultures to assess the ability of the method to detect antimicrobial resistance genes. RESULTS: Sixty-five clinical polymicrobial BC samples (163 total microorganisms) and 30 simulated polymicrobial BC samples (60 strains) were included. BCU reported 84.6% samples as polymicrobial, correctly identified all the bacteria of the mix for 72.3% samples (47/65) and detected bacteria that were missed by the conventional culture for 13.8% samples. All identifications and antimicrobial resistances were accurately detected for 61.5% (40/65) samples. Limitations concerned the detection of anaerobes, enterococci and enterobacterial susceptibility to third generation cephalosporins. BCU results would have guided antimicrobial treatment for 50.8% of the cases (33/65) in a timely and relevant manner, had no impact for 27.7% (18/65) and been misleading for 18.5% (12/65). CONCLUSIONS: Despite some limitations, the Unyvero BCU system is a rapid and reliable method for polymicrobial BC sample analysis.

Prenatal diagnosis of lobar bronchial atresia.

We report three cases of fetal lobar bronchial atresia referred to our Fetal Medicine Center during the mid-trimester of pregnancy over the last 15 years. Lobar bronchial atresia can mimic a main stem bronchial atresia on mid-trimester ultrasound examination as it induces extensive lobar enlargement, major mediastinal shift and eversion of the diaphragm. It was associated with severe pulmonary hypoplasia in all three cases, even though polyhydramnios and ascites were absent in two. Termination of pregnancy was performed at parental request after extensive counseling in each of the cases and necropsy confirmed one or two enlarged lung lobes leading to major compression of the remaining lobe(s) of the ipsilateral lung, the contralateral lung and the heart. No other anomalies were observed and the karyotype was normal in all cases.

[Learning curve of vacuum extraction in residency: a preliminary study]. / Courbe d'apprentissage de la ventouse obstétricale par les internes : étude préliminaire.

OBJECTIVES: The aim of this study was to assess the lurning curve of young residents for vacuum extraction. MATERIALS AND METHODS: All vacuum extractions performed in our department by five residents (< or =5th semester) during a study period of nine months were systematically supervised by a senior who fulfilled an assessment questionnaire from which was calculated a score reflecting the quality of the extraction. RESULTS: Fifty-four vacuum extractions were assessed with a mean of 10.8+/-2.9 (range, 10-13) procedures by resident. We compared the group including the six first procedures performed by each resident (group 1, n = 30) with the group including the following procedures (group 2, n = 24). We observed in the group 2 compared to the group 1, a significant improvement of the scores mean (12.3+/-5.4 vs 8.4+/-6.2, p = 0.016) and a significant reduction of the need for manual assistance by the senior (12.5% vs 40%, p = 0.034). CONCLUSION: We report a method for the learning and assessment of vacuum extraction feasible at "the bed" of the patient. This approach allows to observe a significant progression of the resident for the technique of vacuum extraction on a dozen of procedures.

Untargeted analysis of nanoLC-HRMS data by ANOVA-PCA to highlight metabolites in Gammarus fossarum after in vivo exposure to pharmaceuticals.

In Western Europe, river water quality can be assessed using sentinel species such as the amphipod Gammarus fossarum. In this work of environmental metabolomics, the objective was to develop suitable chemometrics methods, using a limited number of individuals, to assess the modification of the metabolism of G. fossarum exposed to two human pharmaceuticals. Males and females gammarids were exposed to a mixture of the anxiolytic oxazepam and the antiepileptic carbamazepine (1000 ng L-1) for 14 days under laboratory conditions according to a full factorial design 2² (repeated 5 times). They were analyzed at the single individual scale using a method including a µQuEChERS type extraction followed by a nanoliquid chromatography analysis coupled to high-resolution mass spectrometry. The molecular fingerprints obtained were investigated using XCMS. Several corrections of experimental drifts (by using lock mass and Quality Control samples) were tested prior to using APCA + method for the exploitation of the unbalanced designed data. Signal reproducibility was greatly improved by the lock mass normalisation. From the experimental design, a significant effect of both experimental factors "exposure to the mixture" and "gammarid gender" on the signals measured were highlighted by APCA+. Finally, the results obtained made it possible to identify variables responsible for each of the factor effects.

Clinical characteristics and predictive score of dengue vs. chikungunya virus infections.

BACKGROUND: Chikungunya (CHIKV) and dengue viruses (DENV) are two arboviruses with epidemic potential and similar clinical presentations. The potential life-threatening risk associated with DENV justifies an immediate biological assessment and medical follow-up which may be delayed for CHIKV. OBJECTIVES: To compare the clinical variables that would help differentiate patients infected with CHIKV or DENV, and then to compute a predictive score. PATIENTS AND METHOD: Retrospective case-control study comparing CHIKV-infected patients diagnosed by RT-PCR in 2014 with patients infected with DENV diagnosed by positive NS1 antigen test in 2013. Children aged<15 years and pregnant women were excluded. Clinical and biological variables were compared, and a multivariate analysis was performed. A clinical score was developed using the ß coefficients to differentiate the infections. RESULTS: Over the study period 168 patients infected with CHIKV were compared with 452 patients with DENV. The clinical variables independently associated with CHIKV was joint and back pain, and those associated with DENV were headache, muscle pain, nausea/vomiting, diarrhea, and hemorrhagic signs. The clinical score had 98% sensitivity for DENV and a ROC curve of 0.96. CONCLUSION: These two infections have a similar clinical presentation but the use of the proposed clinical score during the acute phase of the disease would make it possible to identify cases of DENV during a CHIKV epidemic to suggest adequate patient management.

[Inductively coupled plasma mass spectrometry. Perspectives in analysis and in biology]. / Spectrométrie de Masse à Plasma couplé par induction (ICP-MS). Potentialités en analyse et en biologie.

ICP-MS is an instrumental method of multi-elementary qualitative and quantitative analysis. It associates with a mass spectrometer (MS) an ion source composed of a plasma torch fed with inductive coupling with a high frequency electromagnetic generator (ICP), similar to that used as a light source in highly-successful Atomics Emission Spectrometry (AES). ICP-MS can be applied to simultaneous analysis of numerous metallic and metalloid elements (80 or so). Its sensitiveness is all in all far better than that available with previous spectrometric techniques, which nevertheless remain more advantageous for processing certain low atomic mass elements. Thanks to its broad dynamic range, ICP-MS allows quantification of an array of elementary concentrations within a single sample. ICP-MS offers particularly interesting perspectives in geochemistry and metal processing, as well as in biochemistry and food or toxicology and environmental analysis. Implementation is rapid and the technique is suitable for series or continuous analyses, or for analysis of any evolving medium such as effluents from gas or liquid chromatography or from capillary electrophoresis, making it a valuable tool for speciation analyses. Finally it enables non-radioactive isotopic labeling, essential for nutritional studies of trace elements, and sufficiently accurate isotopic dilutions, even with more accessible machines.

[Hysteroscopic myomectomy: recurrence and satisfaction survey at short- and long-term]. / Myomectomie hystéroscopique: récidive et enquête de satisfaction à court et long terme.

OBJECTIVES: To assess the postoperative results at short- and long-term after hysteroscopic resection of submucosal myoma giving rise to symptoms. PATIENTS AND METHODS: Retrospective study (University Hospital Estaing, Clermont-Ferrand, France) including patients operated by hysteroscopy in 2004 for one or more submucosal myomas giving rise to symptoms. A survey concerning relapse of symptoms and patient satisfaction was made by phone 4 and 6 years after surgery. RESULTS: Seventy-two patients (mean age: 45.6 years [18-70]) underwent hysteroscopy. At the time of the first survey, the rate of recurrence was 22% (n=15) with 87.5% of cases of recurrence in the first year. Nineteen percent of the patients needed subsequent treatment. The significant factors for the risk of failure of treatment included younger age, number and large size myoma, intramural extension and incomplete resection. In 2010, the overall failure rate was 31.7% (n=20). Fifty percent of the patients who had an incomplete resection required no further treatment. CONCLUSION: In 70% of cases, hysteroscopic resection remains efficient at long-term. Repeat surgery should not be systematic after incomplete resection. The patients must be fully informed, and especially with respect to the risk factors for recurrence.

Determination of chromium in whole blood by DRC-ICP-MS: spectral and non-spectral interferences.

Quantification of chromium in whole blood has been performed by ICP-quadrupole MS. The spectrometer was equipped with a dynamic reaction cell (DRC) with ammonia as reaction gas. The rejection parameter q (RPq) of the DRC and the flow rate of ammonia (NH3) were optimized and set at 0.7 and 0.6 mL min(-1), respectively. Blood was diluted 1:51 (v/v) with an aqueous solution containing 0.1 mg L(-1) NH4OH, 0.1 g L(-1) EDTA, 5 mg L(-1) n-butanol, and 0.1 per thousand Triton X100. Non-spectral matrix effects observed when using the DRC were confirmed by use of vanadium. External calibration with blank and standard solutions prepared in purified water led to biased results for quality control samples. Standard addition calibration was therefore used and its validity verified. By comparing the slopes and calculating residues, it was proved that the plot obtained with standard additions and the plot obtained from blood samples of different concentrations were aligned down to 0.05 microg L(-1) after dilution.

Cell surface localization of proteolysis of human endothelial angiotensin I-converting enzyme. Effect of the amino-terminal domain in the solubilization process.

Angiotensin-converting enzyme (ACE) belongs to the type I class of ectoproteins and is solubilized by Chinese hamster ovary cells transfected with the full-length human ACE cDNA. ACE release in Chinese hamster ovary cells involves a proteolytic cleavage occurring in the carboxyl-terminal region, between Arg-1137 and Leu-1138. The subcellular localization of ACE proteolysis was established by pulse-chase experiments, cell surface immunolabeling, and biotinylation of radiolabeled mature proteins. The proteolysis of ACE takes place primarily at the plasma membrane. The solubilization of ACE is less than 2% within 1 h, is increased 2.4-fold by phorbol esters, but is not influenced by ionophores. An ACE mutant lacking the transmembrane domain and the cytosolic part (ACE delta COOH), is secreted at a faster rate without a carboxyl-terminal cleavage, and phorbol esters or ionophores have no effect on its rate of production in the medium. Therefore, the proteolysis of ACE is dependent on the presence of the membrane anchor and suggests that the secretase(s) involved is also membrane-associated. An ACE mutant lacking the amino-terminal domain (ACECF) is secreted 10-fold faster compared with wild-type ACE. The solubilization of ACECF occurs at the plasma membrane and is stimulated 2.7-fold by phorbol esters, and the cleavage site is localized between Arg-1227 and Val-1228. The amino-terminal domain of ACE slows down the proteolysis and seems to act as a "conformational inhibitor" of the proteolytic process, possibly via interactions with the "stalk" of ACE and the secretase(s) itself.

Autoinduction of 2,4-diacetylphloroglucinol biosynthesis in the biocontrol agent Pseudomonas fluorescens CHA0 and repression by the bacterial metabolites salicylate and pyoluteorin.

The antimicrobial metabolite 2,4-diacetylphloroglucinol (2,4-DAPG) contributes to the capacity of Pseudomonas fluorescens strain CHA0 to control plant diseases caused by soilborne pathogens. A 2, 4-DAPG-negative Tn5 insertion mutant of strain CHA0 was isolated, and the nucleotide sequence of the 4-kb genomic DNA region adjacent to the Tn5 insertion site was determined. Four open reading frames were identified, two of which were homologous to phlA, the first gene of the 2,4-DAPG biosynthetic operon, and to the phlF gene encoding a pathway-specific transcriptional repressor. The Tn5 insertion was located in an open reading frame, tentatively named phlH, which is not related to known phl genes. In wild-type CHA0, 2, 4-DAPG production paralleled expression of a phlA'-'lacZ translational fusion, reaching a maximum in the late exponential growth phase. Thereafter, the compound appeared to be degraded to monoacetylphloroglucinol by the bacterium. 2,4-DAPG was identified as the active compound in extracts from culture supernatants of strain CHA0 specifically inducing phlA'-'lacZ expression about sixfold during exponential growth. Induction by exogenous 2,4-DAPG was most conspicuous in a phlA mutant, which was unable to produce 2, 4-DAPG. In a phlF mutant, 2,4-DAPG production was enhanced severalfold and phlA'-'lacZ was expressed at a level corresponding to that in the wild type with 2,4-DAPG added. The phlF mutant was insensitive to 2,4-DAPG addition. A transcriptional phlA-lacZ fusion was used to demonstrate that the repressor PhlF acts at the level of transcription. Expression of phlA'-'lacZ and 2,4-DAPG synthesis in strain CHA0 was strongly repressed by the bacterial extracellular metabolites salicylate and pyoluteorin as well as by fusaric acid, a toxin produced by the pythopathogenic fungus Fusarium. In the phlF mutant, these compounds did not affect phlA'-'lacZ expression and 2, 4-DAPG production. PhlF-mediated induction by 2,4-DAPG and repression by salicylate of phlA'-'lacZ expression was confirmed by using Escherichia coli as a heterologous host. In conclusion, our results show that autoinduction of 2,4-DAPG biosynthesis can be countered by certain bacterial (and fungal) metabolites. This mechanism, which depends on phlF function, may help P. fluorescens to produce homeostatically balanced amounts of extracellular metabolites.