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Dengue is the arboviral disease that has massively spread in intertropical regions these past few years. The rise in imported cases of dengue and the rapid spread of the Aedes vector mosquitoes in continental France since 2004 explain the occurrence of indigenous dengue cases among the nonimmune population and points to an epidemic risk. Severe dengue cases are rare, but lethality is highest among children under 5 years of age. Like pediatricians in tropical regions, we must learn how dengue presents in metropolitan France and how it can be managed, and pay special attention to severe and potentially fatal forms. The epidemiological, pathophysiological, clinical, diagnostic, and therapeutic characteristics of dengue are presented herein.

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Child travelers are numerous, exposed to the risk of diseases, both infectious and noninfectious, for which practitioners often lack experience. The assessment of febrile returning child travelers is becoming more frequent and challenging. The question of previous travel should be foremost in the checklist of the interview of any febrile child traveler, because this implies a possible tropical disease such as malaria that may be life-threatening. These need to be investigated and treated effectively and rapidly. There are highly contagious infections that could pose public health risks requiring implementation of hygienic and public health measures. A detailed immunization, medical, and travel history for exposure to infectious risks using geographic, seasonal, environmental, sociocultural, and epidemiological data are needed. Along with clinical examination and elementary first-line investigations, the history should guide second-line exams, which will provide the etiology and optimal treatment in approximately 75 % of cases. The majority of children will have a cosmopolitan infection that resolves spontaneously or is simple to treat. Malaria will need urgent and specific treatment. This article describes guidance on first-line evaluation and management of febrile child travelers as recommended in France.

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Treatment of 1-[axial]-(trimethylsilylethynyl)cyclohexan-1-ol with dicobalt octacarbonyl results in a conformational ring flip such that the bulky dicobalt-alkyne cluster moiety now occupies the favored equatorial site. However, when a 4-tert-butyl substituent is present, the coordinated alkynyl group retains its original axial or equatorial position. Complexation of trans-[diaxial]-1,4-bis(triphenylsilylethynyl)cyclohexane-1,4-diol brings about a chair-to-chair conformational inversion such that both cluster fragments now occupy equatorial sites. In contrast, cis-1,4-bis(triphenylsilylethynyl)cyclohexane-1,4-diol reacts with Co(2)(CO)(8) to yield the twist-boat conformer in which the two axial hydroxy substituents exhibit intra-molecular hydrogen bonding. Likewise, the corresponding reaction of cis-1,4-bis(trimethylsilylethynyl)cyclohexane-1,4-diol with Co(2)(CO)(8) leads to a twist-boat, but in this case, the molecules are linked through inter-molecular hydrogen bonds. Eight of these cobalt clusters have been characterized by X-ray crystallography, and the potential use of twist-boats in synthesis is discussed.

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Thirty-one Listeria strains were tested for sensitivity to four class IIa bacteriocins, namely, enterocin A, mesentericin Y105, divercin V41, and pediocin AcH, and to nisin A. Class IIa bacteriocins displayed surprisingly similar antimicrobial patterns ranging from highly susceptible to fully resistant strains, whereas nisin A showed a different pattern in which all Listeria strains were inhibited. Particularly, it was observed that the strain Listeria monocytogenes V7 could not be inhibited by any of the class lIa bacteriocins tested. These observations suggest that Listeria strains resistant to the whole range of class IIa bacteriocins may occur in natural environments, which could be of great concern with regard to the use of these peptides as food preservatives.

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Enterocin A produced by Enterococcus faecium EFM01 displayed a narrow antimicrobial spectrum, mainly directed against Listeria spp. In particular, the bacteriocin was extremely active against 13 Listeria monocytogenes strains. This high specificity of action of enterocin A for Listeria spp. relative to lactic acid bacteria, together with its broad range of activity from pH 4.0 to pH 9.0, are factors which may be of great interest with respect to the potential antilisterial use of this bacteriocin in fermented foods. Assessment of the effect of enterocin A concentration on the extent and kinetics of bactericidal activity on L. monocytogenes Lm 6 (107 cfu ml-1 in culture broth), suggested that viability losses of higher than 5 log10, and time intervals necessary for maximum loss of viability of less than 2 h, could not be obtained. Moreover, it was shown that both parameters are closely dependent on the Listeria strain used. On the other hand, at concentrations inducing destruction of approximately 2 log10 cycles, maximum loss of viability was achieved within time intervals which varied widely from one lactic acid bacteria bacteriocin to another.

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Coral and hydroxyapatite may be used as substitution biomaterials for bone grafts. In this work, we extracted the implants from the femora to study the kinetics of elementary mineral transformation of the osseous substitutes. The use of physical analysis methods such as PIXE (particle-induced X-ray emission) shows that coral and hydroxyapatite, after their implantation in vivo, reach a mineral composition comparable with that of bone. For the first time we have measured the concentration of mineral elements, at different time intervals after implantation, along a cross-section. The distribution according to mineral elements (Ca, P, Sr, Zn, Fe) in the implant, in the receiver site and also at the interface, showed that the kinetics of coral resorption was faster than that of hydroxyapatite; in the same way, the osseous attack was not global but, rather, centripetal.

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An epithermal neutron activation method is used to determine the concentration of mineral elements in human dental enamel. A large number (252) of samples from ancient and modern origins are analyzed. The analytical results are mathematically processed using a statistical multivariant method. This allows to differentiate deciduous from permanent teeth and decayed from sound enamel. It is also possible to distinguish the teeth coming from two different necropoles. The origin and the localization of determined elements in the mineralized part, or in the aqueous-organic part, of enamel is suggested. Their role, as witnessed in the physiopathological phenomena of dental enamel, is discussed.

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Dental enamel is considered to be a biological interface depending on two phenomena the surroundings and the individual's general metabolism. The analysis of its chemical composition is becoming more and more developed. A neutron activation method has been elaborated and applied to these analyses. The results obtained and their statistical interpretation emphasize the fundamental importance of trace elements as a result of their role in the main physiopathological phenomenon peculiar to dental enamel.

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A sensitive capillary gas chromatographic method was developed for the determination of fengabine (a GABAergic antidepressant drug) and some of its metabolites in plasma samples. The method involves a single and rapid liquid-liquid extraction of the parent drug and metabolites from plasma buffered at pH 5, evaporation of the organic phase under nitrogen, derivatization to tert.-butyldimethylsilyl ethers and esters and automatic gas chromatography on a fused-silica, silicone-bonded capillary column coupled to an electron-capture detector. The detection limit for fengabine and other compounds is lower than 1 ng/ml in plasma; the method was successfully applied to pharmacokinetic and drug monitoring clinical studies and tested on more than 2000 biological samples and was found not to suffer from endogenous or exogenous interferences.

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The amount of free water in 50 samples of air-dried enamel from permanent and deciduous teeth was measured by the Karl Fischer method. Samples included both contemporary and burial specimens. The mean values obtained showed that free water constituted about 1% of enamel mass. However, the range of individual values varied considerably, from 0.56 to 1.48%. The proportion of free water did not seem to depend on the patient's age, the type of tooth, or the relationship between the tooth and its oral environment. On the other hand, the deciduous enamel tested displayed a mean free water content that was three times the mean for the permanent teeth (3.01 vs. 1.00%) and the five burial teeth, a mean content of 1.68%.

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A high-performance liquid chromatographic method has been developed for the simultaneous determination of alpidem and its metabolites in human plasma. The method involved a single extraction of the parent drug and metabolites into diethyl ether from alkalinized plasma, evaporation of the organic solution and chromatography of the extracts on a C18 column coupled to a fluorimetric detector. An internal standard was used for the quantitative determination of the compounds. The method was selective for alpidem and three of its metabolites and has a limit of detection of less than 1 ng ml-1 for all the compounds. Since the chromatographic run took more than 20 min, the chromatographic process was fully automated and performed overnight.

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After 32 days of administration to rats of dysprosium in drinking water, this element has been studied by neutron activation analysis in the intra-oral part of the incisors as well as in the molar crowns. This element was absent in the intra-osseous parts of the incisors, the femurs and the liver. After intravenous injection of 13 mg or 26 mg of Dy in several doses over 32 days, this element was found in the incisor formation and maturation zones as well as in the part having erupted in the oral cavity. It was also found in the molars, the femurs and the liver. The structural study has shown that no cytotoxic effect was observed with the dysprosium doses used. Dentinogenesis and amelogenesis were not disturbed. The final structures were homogeneous. By comparing the two administration ways of dysprosium we have at our disposal a study model using an inducible tracer of the incorporation of adsorption of a mineral element in dental structures during early or late maturations.

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Congenital CSF otorrhea is seldom the cause of meningitis but has to be looked for especially if associated with a dead ear or with recurrent meningitis. Polytomograms of the mastoids are essential to rule out any abnormality of the internal ear. Three patients with a congenital CSF otorrhea and associated meningitis are reviewed. They all presented a Mondini type of dysplasia and had an oval window fistula. They were treated successfully with fascia and muscle obliteration of the vestibule.

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