Comparison of the dental health status of 8 to 14-year-old children in France and in Jordan, a country of endemic fluorisis

In the present paper, data obtained from a survey dealing with dental carie, dental fluorosis and gingival health, involving 2618 Jordanian schoolchildren, aged 8 to 14, were compared with data from another survey dealing with 1058 schoolchildren of the same age groups living in a non-fluoridated area in the west of France. As regards dental carie in temporary teeth,  up to the age of 12, the dft and dfs scores were higher in France than in Jordan. Over the age of 12, the difference was no longer significant. As regards dental carie in permanent teeth, the data showing that Jordanian children are less subject to caries than the French were very highly significant. Also, it was shown that caries index in girls was higher than in boys.These data were not significant in the French survey, but highly significant in the Jordanian investigation.A possible explanation is that, due to the custom of the country, boys in Jordan drink much more tea (with high fluoride content) than girls. As regards gingival health, an interesting finding was that, compared to the French children, the percentage of Jordanian children presenting gingivitis is remarkably low. The fluoride content of the dental plaque might play a restricting and preventing role.Les résultats d’une enquête sur la carie dentaire, la fluorose et la gingivite, menée en Jordanie chez 2618 écoliers de 8 à 14 ans, ont été comparés avec ceux d’une enquête menée en France chez 1058 écoliers de mêmes âges, dans l’Ouest de la France, où l’eau de boisson n’est pas fluorée. En ce qui concerne la carie des dents temporaires, les indices en France sont plus élevés qu’en Jordanie, mais la différence n’est plus significative après l’âge de 12 ans. Pour les dents permanentes, les résultats indiquent, de façon très significative, que les enfants Jordaniens sont moins atteints par la carie que les français. Les filles, dans les deux enquêtes, sont plus atteintes que les garçons, mais la différence n’est pas significative dans l’enquête française, alors qu’elle est très significative dans l’enquête jordanienne. La raison pourrait être qu’en Jordanie, la coutume du pays veut que les garçons participent très tôt aux rites de la vie quotidienne et boivent davantage de thé (très fluoré) que les filles. En ce qui concerne la gingivite, le pourcentage des enfants atteints en Jordanie est très bas, comparé à ce qu’il est en France. Le contenu en fluor de la plaque pourrait jouer un rôle limitatif et protecteur

Morphologic examination of the temporal bone by cone beam computed tomography: Comparison with multislice helical computed tomography

SummaryIntroductionHigh-resolution CT imaging is essential to diagnosis and follow-up of temporal bone pathology. Morphologically, CT is the reference examination. The requirement of long-term follow-up thus exposes patients to cumulative radiation doses. Limiting exposure to ionizing radiation is an increasing concern of public health authorities. The principal advantage of Cone Beam CT (CBCT) lies in a significant reduction in radiation dose. The main objective of the present study was to assess the morphologic concordance between CBCT and Multislice Helical Computed Tomography (MSCT) on 20 anatomic landmarks corresponding to regions of interest in clinical practice. The secondary objectives were to compare the two techniques qualitatively in stapes and footplate assessment and measurement of footplate thickness, and quantitatively in terms of dosimetry.Material and methodsAn experimental anatomical study was performed on 12 temporal bones from fresh human cadavers of unknown clinical history. Each underwent CBCT and MSCT.ResultsThere was no significant difference in morphologic assessment of the temporal bones on the two techniques. Exploration of the stapes, incudostapedial joint, anterior stapediovestibular joint and footplate was qualitatively more precise on CBCT, and footplate thickness showed less overestimation than on MSCT. CBCT delivered 22 times less radiation than MSCT under the present experimental conditions.ConclusionCBCT provides reliable morphologic assessment of temporal bone, thanks to higher spatial resolution than on MSCT, with significantly reduced radiation dose

Le rôle de la consommation du thé dans la fluorose dentaire en Jordanie

2.516 children of both sexes, six to fourteen years old, were examined in Jordan in the course of an epidemiological study. 81,11 % of girls and 76,43% of boys presented severe forms of dental fluorosis according to DEAN’s index.Drinking water analysis revealed fluoride concentrations ranging from 0,27 to 1,4 mg F/l. These concentrations are neighbouring optimum tolerated fluoride supplementation in drinking water. However high annual temperature mean and ten hours daily sunshining must also be taken in consideration. For social and climatic reasons, jordanian children drink daily high quantities of tea. Analysis of tea prepared on jordanian way revealed a concentration of 1,2 mg F/l. This continuous intake of fluoride might explain the high severity of dental fluorosis in Jordan.Dans le cadre d’une enquête sur la fluorose dentaire en Jordanie, 2.516 enfants de six à quatorze ans, filles et garçons, répartis sur l’ensemble du pays ont été examinés. 81,11% des filles et 76,43% des garçons se situent dans les deux classes les plus sévères de la fluorose selon la classification de DEAN.L’analyse de l’eau de consommation a relevé des concentrations en fluor variant de 0,27 mg F/l à 1,4 mg F/l, selon les régions et les sources. Ces concentrations en fluor ne dépassent pas le seuil tolérable pour éviter la fluorose dentaire. Mais à cela, s’ajoute une moyenne annuelle de température élevée ( 14 º à 24º C) et une moyenne d’ensoleillement journalier de dix heures. Pour des raisons sociales et climatiques, la population jordanienne consomme dès l’enfance, une grande quantité de boisson journalière, essentiellement sous forme de thé. Le dosage de fluor dans le thé préparé selon la méthode jordanienne a donné une concentration moyenne de 1,2 mg F/l.Cette absorption continue de thé apporte un excès de fluor permettant vraisemblablement d’expliquer en partie la sévérité de la fluorose dentaire en Jordanie

Growth hormone secretagogues exert differential effects on skeletal muscle calcium homeostasis in male rats depending on the peptidyl/non-peptidyl structure

TheorexigenicandanaboliceffectsinducedbyghrelinandthesyntheticGHsecretagogues(GHSs) are thought to positively contribute to therapeutic approaches and the adjunct treatment of a number of diseases associated with muscle wasting such as cachexia and sarcopenia. However, manyquestionsaboutthepotentialutilityandsafetyofGHSsinboththerapyandskeletalmuscle functionremainunanswered.Byusingfura-2cytofluorimetrictechnique,wedeterminedtheacute effectsofghrelin,aswellasofpeptidylandnonpeptidylsyntheticGHSsoncalciumhomeostasis, a critical biomarker of muscle function, in isolated tendon-to-tendon male rat skeletal muscle fibers.ThesyntheticnonpeptidylGHSs,butnotpeptidylghrelinandhexarelin,wereabletosignificantlyincreaserestingcytosoliccalcium[Ca2]i.ThenonpeptidylGHS-induced[Ca2] iincrease was independent of GHS-receptor 1a but was antagonized by both thapsigargin/caffeine and cyclosporineA,indicatingtheinvolvementofthesarcoplasmicreticulumandmitochondria.EvaluationoftheeffectsofapseudopeptidylGHSandanonpeptidylantagonistoftheGHS-receptor 1a together with a drug-modeling study suggest the conclusion that the lipophilic nonpeptidyl structureofthetestedcompoundsisthekeychemicalfeaturecrucialfortheGHS-inducedcalcium alterationsintheskeletalmuscle.Thus,syntheticGHSscanhavedifferenteffectsonskeletalmuscle fibersdependingontheirmolecularstructures.Thecalciumhomeostasisdysregulationspecifically induced by the nonpeptidyl GHSs used in this study could potentially counteract the beneficial effects associated with these drugs in the treatment of muscle wasting of cachexia- or other age-related disorders

Thermocapillary actuation of liquid flow on chemically patterned surfaces

We have investigated the thermocapillary flow of a Newtonian liquid on hydrophilic microstripes which are lithographically defined on a hydrophobic surface. The speed of the microstreams is studied as a function of the stripe width w, the applied thermal gradient |dT/dx| and the liquid volume V deposited on a connecting reservoir pad. Numerical solutions of the flow speed as a function of downstream position show excellent agreement with experiment. The only adjustable parameter is the inlet film height, which is controlled by the ratio of the reservoir pressure to the shear stress applied to the liquid stream. In the limiting cases where this ratio is either much smaller or much larger than unity, the rivulet speed shows a power law dependency on w, |dT/dx| and V. In this study we demonstrate that thermocapillary driven flow on chemically patterned surfaces can provide an elegant and tunable method for the transport of ultrasmall liquid volumes in emerging microfluidic technologies

Molecular Weight Dependence of Spreading Rates of Ultrathin Polymeric Films

We study experimentally the molecular weight $M$ dependence of spreading rates of molecularly thin precursor films, growing at the bottom of droplets of polymer liquids. In accord with previous observations, we find that the radial extension R(t) of the film grows with time as R(t) = (D_{exp} t)^{1/2}. Our data substantiate the M-dependence of D_{exp}; we show that it follows D_{exp} \sim M^{-\gamma}, where the exponent \gamma is dependent on the chemical composition of the solid surface, determining its frictional properties with respect to the molecular transport. In the specific case of hydrophilic substrates, the frictional properties can be modified by the change of the relative humidity (RH). We find that \gamma \approx 1 at low RH and tends to zero when RH gets progressively increased. We propose simple theoretical arguments which explain the observed behavior in the limits of low and high RH.Comment: 4 pages, 2 figures, to appear in PR

Identification of baryon resonances in central heavy-ion collisions at energies between 1 and 2 AGeV

The mass distributions of baryon resonances populated in near-central collisions of Au on Au and Ni on Ni are deduced by defolding the $p_t$ spectra of charged pions by a method which does not depend on a specific resonance shape. In addition the mass distributions of resonances are obtained from the invariant masses of $(p, \pi^{\pm})$ pairs. With both methods the deduced mass distributions are shifted by an average value of -60 MeV/c$^2$ relative to the mass distribution of the free $\Delta(1232)$ resonance, the distributions descent almost exponentially towards mass values of 2000 MeV/c^2. The observed differences between $(p, \pi^-)$ and $(p, \pi^+)$ pairs indicate a contribution of isospin $I = 1/2$ resonances. The attempt to consistently describe the deduced mass distributions and the reconstructed kinetic energy spectra of the resonances leads to new insights about the freeze out conditions, i.e. to rather low temperatures and large expansion velocities.Comment: 30 pages, 13 figures, Latex using documentstyle[12pt,a4,epsfig], to appear in Eur. Phys. J.

Stopping and Radial Flow in Central 58Ni + 58Ni Collisions between 1 and 2 AGeV

The production of charged pions, protons and deuterons has been studied in central collisions of 58Ni on 58Ni at incident beam energies of 1.06, 1.45 and 1.93 AGeV. The dependence of transverse-momentum and rapidity spectra on the beam energy and on the centrality of the collison is presented. It is shown that the scaling of the mean rapidity shift of protons established for AGS and SPS energies is valid down to 1 AGeV. The degree of nuclear stopping is discussed; the IQMD transport model reproduces the measured proton rapidity spectra for the most central events reasonably well, but does not show any sensitivity between the soft and the hard equation of state (EoS). A radial flow analysis, using the midrapidity transverse-momentum spectra, delivers freeze-out temperatures T and radial flow velocities beta_r which increase with beam energy up to 2 AGeV; in comparison to existing data of Au on Au over a large range of energies only beta_r shows a system size dependence

Abundance of Delta Resonances in 58Ni+58Ni Collisions between 1 and 2 AGeV

Charged pion spectra measured in 58Ni-58Ni collisions at 1.06, 1.45 and 1.93 AGeV are interpreted in terms of a thermal model including the decay of Delta resonances. The transverse momentum spectra of pions are well reproduced by adding the pions originating from the Delta-resonance decay to the component of thermal pions, deduced from the high transverse momentum part of the pion spectra. About 10 and 18% of the nucleons are excited to Delta states at freeze-out for beam energies of 1 and 2 AGeV, respectively.Comment: 14 pages, LaTeX with 3 included figures; submitted to Physics Letters