Influence d'une hospitalisation prénatale sur les facteurs de stress parentaux lors d'une naissance prématurée [Influence of prenatal hospitalization on parental stressful experience in the case of a premature birth].

OBJECTIVES: To investigate the influence of prenatal hospitalization before a premature birth, on the parental stressful experience, parental symptoms of post-traumatic stress and quality of parent-infant interaction during the hospitalization in neonatology. POPULATION AND METHODS: Population: 51 preterm infants born and 25 full term infants control. Four groups: controls, premature without prenatal hospitalization, premature with a short (<8 days) prenatal hospitalization and premature with a long (≥8 days) prenatal hospitalization. Instruments: the Parental Stressor Scale: Neonatal Intensive Care Unit (PSS: NICU, Miles et al., 1993 [14]) and the Perinatal PTSD Questionnaire (PPQ, Quinnell and Hynan, 1999 [16]). RESULTS: When prenatal hospitalization of the mother occurred, parents acknowledged increased stress induced by the environmental factors during the infant's hospitalization. Furthermore, mothers from the group with a short prenatal hospitalization presented significantly more symptoms of post-traumatic stress. Parents presenting more symptoms of post-traumatic stress describe a significantly more difficult interaction with their infant in neonatology. CONCLUSION: This study highlights the necessity to deliver special care to women hospitalized shortly (<8 days) prior to the delivery of their premature baby. This group is at high risk of presenting post-traumatic stress symptoms, which could have a negative impact on the quality of parent-infant interactions.

Importance of genotypic and phenotypic tolerance in the treatment of experimental endocarditis due to Streptococcus gordonii.

Genotypic and phenotypic tolerance was studied in penicillin treatment of experimental endocarditis due to nontolerant and tolerant Streptococcus gordonii and to their backcross transformants. The organisms were matched for in vitro and in vivo growth rates. Rats with aortic endocarditis were treated for 3 or 5 days, starting 12, 24, or 48 h after inoculation. When started at 12 h, during fast intravegetation growth, 3 days of treatment cured 80% of the nontolerant parent compared with &lt;30% of the tolerant derivative (P &lt; .005). When started at 24 or 48 h and if intravegetation growth had reached a plateau, 3 days of treatment failed against both bacteria. However, a significant difference between the 2 organisms was restored when treatment was extended to 5 days. Thus, genotypic tolerance conferred a survival advantage in both fast- and slow-growing bacteria, demonstrating that the in vitro-defined tolerant phenotype also carried the risk of treatment failure in vivo.

New evidence for the social embeddedness of infants' early triangular capacities.

Infants appear to be active participants in complex interactional sequences with their parents far earlier than previously theorized. In this report, we document the capacity of 3-month-old infants to share attention with two partners (mothers and fathers) simultaneously, and trace links between this capacity and early family group-level dynamics. During comprehensive evaluations of the family's emergent coparenting alliance completed in 113 homes, we charted infants' eye gaze patterns during two different mother-father-infant assessment paradigms. Triangular capacities (operationalized as the frequency of rapid multishift gaze transitions between parents during interactions) were stable across interaction context. Infants exhibiting more advanced triangular capacities belonged to families showing evidence of better coparental adjustment. Theoretical and practice implications of these findings are discussed.

Biotic Factors Affecting Expression of the 2,4-Diacetylphloroglucinol Biosynthesis Gene phlA in Pseudomonas fluorescens Biocontrol Strain CHA0 in the Rhizosphere.

ABSTRACT Production of the polyketide antimicrobial metabolite 2,4-diacetyl-phloroglucinol (DAPG) is a key factor in the biocontrol activity of Pseudomonas fluorescens CHA0. Strain CHA0 carrying a translational phlA'-'lacZ fusion was used to monitor expression of the phl biosynthetic genes in vitro and in the rhizosphere. Expression of the reporter gene accurately reflected actual production of DAPG in vitro and in planta as determined by direct extraction of the antimicrobial compound. In a gnotobiotic system containing a clay and sand-based artificial soil, reporter gene expression was significantly greater in the rhizospheres of two monocots (maize and wheat) compared with gene expression in the rhizospheres of two dicots (bean and cucumber). We observed this host genotype effect on bacterial gene expression also at the level of cultivars. Significant differences were found among six additional maize cultivars tested under gnotobiotic conditions. There was no difference between transgenic maize expressing the Bacillus thuringiensis insecticidal gene cry1Ab and the near-isogenic parent line. Plant age had a significant impact on gene expression. Using maize as a model, expression of the phlA'-'lacZ reporter gene peaked at 24 h after planting of pregerminated seedlings, and dropped to a fourth of that value within 48 h, remaining at that level throughout 22 days of plant growth. Root infection by Pythium ultimum stimulated bacterial gene expression on both cucumber and maize, and this was independent of differences in rhizosphere colonization on these host plants. To our knowledge, this is the first comprehensive evaluation of how biotic factors that commonly confront bacterial inoculants in agricultural systems (host genotype, host age, and pathogen infection) modulate the expression of key biocontrol genes for disease suppression.

Residual antimalarials in malaria patients from Tanzania--implications on drug efficacy assessment and spread of parasite resistance.

Repeated antimalarial treatment for febrile episodes and self-treatment are common in malaria-endemic areas. The intake of antimalarials prior to participating in an in vivo study may alter treatment outcome and affect the interpretation of both efficacy and safety outcomes. We report the findings from baseline plasma sampling of malaria patients prior to inclusion into an in vivo study in Tanzania and discuss the implications of residual concentrations of antimalarials in this setting. In an in vivo study conducted in a rural area of Tanzania in 2008, baseline plasma samples from patients reporting no antimalarial intake within the last 28 days were screened for the presence of 14 antimalarials (parent drugs or metabolites) using liquid chromatography-tandem mass spectrometry. Among the 148 patients enrolled, 110 (74.3%) had at least one antimalarial in their plasma: 80 (54.1%) had lumefantrine above the lower limit of calibration (LLC = 4 ng/mL), 7 (4.7%) desbutyl-lumefantrine (4 ng/mL), 77 (52.0%) sulfadoxine (0.5 ng/mL), 15 (10.1%) pyrimethamine (0.5 ng/mL), 16 (10.8%) quinine (2.5 ng/mL) and none chloroquine (2.5 ng/mL). The proportion of patients with detectable antimalarial drug levels prior to enrollment into the study is worrying. Indeed artemether-lumefantrine was supposed to be available only at government health facilities. Although sulfadoxine-pyrimethamine is only recommended for intermittent preventive treatment in pregnancy (IPTp), it was still widely used in public and private health facilities and sold in drug shops. Self-reporting of previous drug intake is unreliable and thus screening for the presence of antimalarial drug levels should be considered in future in vivo studies to allow for accurate assessment of treatment outcome. Furthermore, persisting sub-therapeutic drug levels of antimalarials in a population could promote the spread of drug resistance. The knowledge on drug pressure in a given population is important to monitor standard treatment policy implementation.

Maturation-dependent effects of chlorpyrifos and parathion and their oxygen analogs on acetylcholinesterase and neuronal and glial markers in aggregating brain cell cultures.

An in vitro model, the aggregating brain cell culture of fetal rat telencephalon, has been used to study the maturation-dependent sensitivity of brain cells to two organophosphorus pesticides (OPs), chlorpyrifos and parathion, and to their oxon derivatives. Immature (DIV 5-15) or differentiated (DIV 25-35) brain cells were treated continuously for 10 days. Acetylcholinesterase (AChE) inhibitory potency for the OPs was compared to that of eserine (physostigmine), a reversible AChE inhibitor. Oxon derivatives were more potent AChE inhibitors than the parent compounds, and parathion was more potent than chlorpyrifos. No maturation-dependent differences for AChE inhibition were found for chlorpyrifos and eserine, whereas for parathion and paraoxon there was a tendency to be more effective in immature cultures, while the opposite was true for chlorpyrifos-oxon. Toxic effects, assessed by measuring protein content as an index of general cytotoxicity, and various enzyme activities as cell-type-specific neuronal and glial markers (ChAT and GAD, for cholinergic and GABAergic neurons, respectively, and GS and CNP, for astrocytes and oligodendrocytes, respectively) were only found at more than 70% of AChE inhibition. Immature compared to differentiated cholinergic neurons appeared to be more sensitive to OP treatments. The oxon derivates were found to be more toxic on neurons than the parent compounds, and chlorpyrifos was more toxic than parathion. Eserine was not neurotoxic. These results indicate that inhibition of AChE remains the most sensitive macromolecular target of OP exposure, since toxic effects were found at concentrations in which AChE was inhibited. Furthermore, the compound-specific reactions, the differential pattern of toxicity of OPs compared to eserine, and the higher sensitivity of immature brain cells suggest that the toxic effects and inhibition of AChE are unrelated.