[An epidemiological study of early consultations of newborns in pediatric emergency units]. / Étude épidémiologique des consultations précoces de nouveau-nés aux services d'accueil des urgences pédiatriques.

BACKGROUND: The number of visits to the pediatric emergency services has increased in the past 20 years in France and around the world, especially for neonates (under 28 days of age). OBJECTIVES: Determine for neonates the reasons requiring medical consultation in the emergency pediatric unit of Saint-Etienne University Hospital (France) and isolate the proportion of "non-urgent" preventable consultations that could be managed outside of emergency units. METHOD: Epidemiological, retrospective study on computerized data on neonates who were referred to the pediatric emergency unit of the Saint-Étienne University Hospital from 1 January to 31 December 2011. Four composite criteria "child not addressed by a healthcare professional; severity score G1, G2, G3 based on an internal scale; no further review undertaken; and return home" were used to define "non-urgent" consultations. RESULTS: A total of 419 infants were included in the study. The leading reasons for consultations were crying (14.1%), vomiting (11.9%), chest tightness (10.7%), fever (8.1%), and diarrhea (7%). The main diagnoses were acute nasopharyngitis (11.5%), gastroesophageal reflux (10%), colic (8.1%), and excessive parental anxiety (7.6%). The percentage of "non-urgent" consultations was 52.4%. CONCLUSIONS: Final diagnoses are quite similar to the reasons for consultation. The baby's unexplained crying and the inexperience of young parents resulted in an irrational anxiety. This study highlights the need for parental support at home after discharge from the maternity ward and the use of large-scale educational initiatives.

Glycolipid-anchored acetylcholinesterases from rabbit lymphocytes and erythrocytes differ in their sensitivity to phosphatidylinositol-specific phospholipase C.

The type of membrane association of acetylcholinesterase (AChE, EC 3.1.1.7) was studied in rabbit lymphocytes and erythrocytes. In both cases, the unique AChE molecular form was an amphiphilic dimer (referred to as G2a) anchored in the membrane by a glycosylphosphatidylinositol. In lymphocytes, G2a AChE was directly converted into its hydrophilic G2h counterpart by a treatment with Bacillus thuringiensis phosphatidylinositol-phospholipase C (PI-PLC, EC 3.1.4.10). In erythrocytes, AChE was resistant to PI-PLC but was rendered sensitive by a prior deacylation with alkaline hydroxylamine. This observation suggests that, as previously reported for human erythrocyte AChE, an acylation of the inositol ring in the glycolipid anchor of rabbit erythrocyte AChE (that does not occur in lymphocytes) prevents the cleavage.

Acetylcholinesterases of the nematode Steinernema carpocapsae. Characterization of two types of amphiphilic forms differing in their mode of membrane association.

We analyzed the molecular forms of acetylcholinesterase (AChE) in the nematode Steinernema carpocapsae. Two major AChEs are involved in acetylcholine hydrolysis. The first class of AChE is highly sensitive to eserine (IC50 = 0.05 microM). The corresponding molecular forms are: an amphiphilic 14S form converted into a hydrophilic 14.5S form by mild proteolysis and two hydrophilic 12S and 7S forms. Reduction of the amphiphilic 14S form with 10 mM dithiothreitol produces hydrophilic 7S and 4S forms, indicating that it is an oligomer of hydrophilic catalytic subunits linked by disulfide bond(s) to a hydrophobic structural element that confers the amphiphilicity to the complex. Sedimentation coefficients suggest that 4S, 7S, 12S forms correspond to hydrophilic monomer, dimer, tetramer and that the 14S form is also a tetramer linked to one structural element. The second class of AChE is less sensitive to eserine (IC50 = 0.1 mM). Corresponding molecular forms are hydrophilic and amphiphilic 4S forms (monomers) and a major amphiphilic 7S form converted into a hydrophilic dimer by Bacillus thuringiensis phosphatidylinositol-specific phospholipase C. This amphiphilic 7S form thus possesses a glycolipid anchor. It appears that Steinernema (a very primitive invertebrate) presents AChEs with two types of membrane association that closely resemble those described for amphiphilic G2 and G4 forms of AChE in more evolved animals.