Three-dimensional reconstruction of the temporal bone: Comparison of in situ, CT, and CBCT measurements.

OBJECTIVE: To evaluate the accuracy of three-dimensional (3D) Cone Beam Computed Tomography (CBCT) and Computed Tomography (CT) reconstructions of human temporal bones compared with in situ measurements. MATERIAL AND METHODS: Experimental anatomical study of 10 human temporal bones. Wilcoxon's test was used to compare 8 distances on each temporal bone measured in situ and then on 3D CT and CBCT reconstructions. Six landmarks were used: external auditory canal (EAC), tip of the mastoid process, tip of the occiput, zygoma, a point situated 1cm above the tip of the mastoid process (T0) (open technique: lower limit of the mastoidectomy), head of stapes. RESULTS: No significant difference was observed between the 3 measuring techniques for any of the distances studied (P>0.05). DISCUSSION: This study demonstrates the equivalence of CBCT and CT for temporal bone measurements. CONCLUSION: CBCT is a new imaging modality providing 3D reconstructions of the temporal bone that are as reliable as those obtained by CT. As a result of better spatial resolution compared to CT, CBCT is associated with a significantly lower radiation dose. This technique constitutes a morphological progress, as CBCT is comparable to CT, allowing investigation of pathological ears with a lower radiation dose.

Familial aggregation in giant cell arteritis and polymyalgia rheumatica: a comprehensive literature review including 4 new families.

OBJECTIVE: To review personal and published observations of giant cell (temporal) arteritis (GCA) or polymyal-gia rheumatica (PMR) with familial or conjugal aggregation and emphasise on epidemiological, clinical and genetic features of such cases. METHODS: We pooled data obtained from all cases of GCA or PMR with familial aggregation recruited in the department since 1976 and those from reports of familial or conjugal GCA or PMR published in the French-English literature since 1970. RESULTS: During the study period, we diagnosed 460 patients (128 with isolated PMR, 227 with isolated GCA, 105 with PMR/CGA). No conjugal couples were observed in the whole series. No familial cases were identified among PMR patients, whereas the prevalence of familial GCA was 1 in 83 (1 in 250 to 500 expected by chance), as we identified 4 patients (brother-brother, sister with history of affected sister, and daughter with priory affected mother). An additional pair of sisters with TA, recruited several months after diagnosis, is also presented. Pooling data from 85 patients (74 with GCA) including our patients, representing 32 families and 8 conjugal pairs, enabled us to draw the following observations: 1) partial or full agreement in the clinical picture (GCA, PMR, or GCA/PMR) was observed in 96% of the siblings pairs, suggesting a common pathogenic mechanism; 2) five kindred were described in whom at least three members were affected; 3) the lag between manifested diseases in familial or conjugal pairs averaged 5.7 years, with synchronous or close disease occurrence in only 26% of the pairs; 4) 18 of 32 assessed patients (56%) carried the DR4 antigen. CONCLUSION: Our survey on familial aggregation of GCA and PMR accumulated data pointing to a genetic predisposition. However, environmental contagious factors could have trigger synchronous disease onset in up to one-fourth of the cases.

Application of the Bahe's pseudolattice theory to water-1-butyl-3-methylimidazolium tetrafluoroborate (bmimBF4) mixtures at 298.15K: Part II. Acidity scales.

Molten salts at room temperature and their mixtures with water or molecular solvents are excellent candidates for future replacement of most of organic solvents used in many industrial processes. To make this possible and to allow efficient application, it is necessary to determine physico-chemical parameters (such as the acidity scales) for these reaction media. This work follows a study of the autoprotolysis constants (K(s)) of water-1-butyl-3-methylimidazolium tetrafluoroborate (bmimBF(4)) mixtures at 298.15K over the composition range of 0-77.43 vol.% bmimBF(4) [I. Bou Malham, P. Letellier, M. Turmine, Talanta 72 (2007) 155-164]. In this second analysis, we determined the values of the dissociation constant (pK(a)) of various conjugate acid-base pairs for the same water-bmimBF(4) mixtures, to establish acidity scales for each medium. These data can be used to produce proton buffer solutions and thus to control the acidity level of water-ionic liquid (IL) mixtures. We compare the values of pK(a) for acid-base pairs in water-bmimBF(4) mixtures with published values for water-methanol mixtures.

[Salivary nitrates. New perspectives concerning the physiological function of saliva]. / Les nitrates salivaires. Nouvellesperspectives concernant les fonctions physiologiques de la salive.

For many years, nitrate ions have been thought to be "toxic agents", but scientific reality seems very different. The source of nitrate ions is double: exogenous and endogenous, and the metabolism of nitrates is partly salivary. The strong concentration of nitrate ions in saliva has many beneficial physiological effects. Salivary nitrate has anti-infectious effects on the oral cavity and all along the digestive tract. They give cardiovascular protection, are instrumental in the adaptive relaxation of the stomach by acting on smooth stomach muscles and have a protective action on the gastric mucosa.

Application of the Bahe's pseudolattice-theory to water-1-butyl-3-methylimidazolium tetrafluoroborate (bmimBF(4)) mixtures at 298.15K Part I. Autoprotolysis constants.

The autoprotolysis constants (K(s)) of water - 1-butyl-3-methylimidazolium tetrafluoroborate (bmimBF(4)) mixtures were determined at 298K over the composition range of 0 to 77.43vol.% bmimBF(4) using potentiometric method with a glass electrode. A slight increase in the autoprotolysis constant was observed when the salt was added to the water. The value of the ionic product of the medium then decreases as the bmimBF(4) content increases from about 20vol.%. The acid-base properties of these media were perfectly described by Bahe's approaches that were completed by Varela et al. concerning structured electrolyte solutions with large short-range interactions.

[Photodistribution of varicella in an adult]. / Photodistribution d'une varicelle chez un adulte.

INTRODUCTION: Exacerbation of viral exanthema has been described after different types of aggression such as sun exposure. Photoaggravation of varicella is unusual. CASE REPORT: We report the case of a 25 year-old woman who presented with varicella mainly distributed on the neckline and the top of the back. During the viral incubation she had been sunburnt in these areas. DISCUSSION: The clinical lesions and the evolution of a photoaggravated varicella differs from those of classical varicella. The vesicles are selectively distributed on areas previously sunburned or suntanned. The more tanned or more erythematous the area is, the greater the number of lesions. They are often at the same stage of development and the course can be shortened with only one or two progressive phases. Inflammatory modifications secondary to ultraviolet exposure induces in photoexposed areas an increase in vascular flow and also an increase in capillary permeability, which can promote diapedesis of the lymphocytes or the transit of viral particles. Therefore, sun exposure during the incubation of the virus can enhance the deposit of viral pArticles in the cutaneous areas submitted actinic stress. The amount of virus in sun exposed areas is greater than in the non-exposed ones.

A potentiometric study of the adsorption of a cationic surfactant onto laponite in water-methanol and water-dimethylsulfoxide mixtures.

We studied the adsorption of a cationic surfactant, dodecyltrimethylammonium bromide (DTABr), onto laponite in water-methanol and water-DMSO mixtures at 298 K. Adsorption isotherms were determined by potentiometric methods using DTA(+) and Br(-)-selective electrodes. All of the isotherm shapes in the mixture were classical. Activity coefficients were determined for the transfer between water and hydroorganic mixtures. Comparison of the adsorption isotherms obtained for different surfactant chemical potentials showed that at higher concentrations of free surfactant, the aggregation state does not depend on the nature of the surrounding media. A study of the influence of the ionic strength showed that there is a common intersection point in each hydroorganic mixture. This point corresponds to the charge compensation point and depends on the nature of the surrounding medium.

Lower limb giant cell arteritis and temporal arteritis: followup of 8 cases.

Among 8 patients with giant cell arteritis (GCA) (6 women, 2 men) whose clinical presentations were compatible with temporal arteritis (TA), 6 were followed for 37-105 (mean 74.9) months, one died shortly after treatment onset, and the last was asymptomatic (10 mg steroids/day) when lost to followup at 29 months. All 8 patients had bilateral leg claudication of recent onset; for 6 patients, this was the first symptom. All leg angiograms showed multiple, bilateral, long and smooth stenoses, thromboses, or both. Biopsies of diseased leg arteries from 4 patients provided histological proof of GCA; another case was histologically proven post mortem. Among the 5 patients who met at least 3 American College of Rheumatology criteria of GCA or TA, 3 without histologically documented leg GCA also had biopsy proven temporal GCA (n = 1), or headaches and claudication and angiographic inflammatory arteritis of the arms (n = 2). All patients received steroids; 3 had bypasses, one with endarterectomy. Five are asymptomatic after 24-100 months of steroids (mean 50.6). Revascularization was not successful; one amputation was necessary. Large artery involvement in GCA can affect the legs. Bilateral and rapidly progressive intermittent claudication of recent onset is the most common symptom, even in the absence of headaches or the presence of a silent inflammatory syndrome. Early diagnosis allows rapid initiation of steroid therapy, which is usually able to generate a sufficiently good response to avoid vascular surgery.

Ion-selective electrode for dodecyldimethylamine oxide: a "twice-Nernstian" slope for the determination of a neutral component

An electrode originally sensitive to dodecyltrimethylammonium (DTA+) was proven to be sensitive to dodecyldimethylamine oxide (DDAO), a surfactant with acidobasic properties. The response of the electrode was tested from pH 2 to 9.3. Its slope is Nernstian when the surfactant is entirely protonated. At a pH where the molecule is mainly under the neutral form, the electrode responds with a "twice-Nernstian" slope around 120 mV/decade. The validity of this electrode for measurements was checked by confronting the evolution of the critical micelle concentration of DDAO vs pH with data already published and by determining the complexation constant of DDAO and beta-cyclodextrin. A possible explanation of the "twice-Nernstian" slope, using a dimer of DDAO is proposed.

Thermodynamic Approach to the Wetting of Solids by Surface-Active Agents: A Supplementary Approach to the Gibbs Formalism.

The adsorption of a solute on a solid can be followed by contact angle measurements of a drop of the solution on the solid. The Gibbs isotherm model can be used for quantitative interpretation of wettability variations. Its use in linking the wettability to the adsorption isotherm involves assimilating the Gibbs' planes to the surfaces themselves. Within this framework, these interpretations lead to the conclusion that adsorption of surface-active agents is greater on solid-vapor interfaces than on solid-liquid interfaces, for hydrophilic solids. This is not the only approach. Thermodynamics allows other formalisms, the conclusions of which can be completely different. We present a thermodynamic approach which explicitly reveals relationships between surface tensions and contents of surfaces, without referring to the Gibbs' plane. This permits us to explain the behavior of a drop of surfactant solution put on hydrophilic or hydrophobic solids with conclusions different from those reached using the Gibbs approach. We show that all these thermodynamic approaches are linked; they do not dismiss one another but give different views of the same phenomenon. Copyright 2000 Academic Press.

A randomized, multicenter, controlled trial using intravenous pulses of methylprednisolone in the initial treatment of simple forms of giant cell arteritis: a one year followup study of 164 patients.

OBJECTIVE: (1) To evaluate the corticosteroid sparing effect of an initial intravenous (i.v.) pulse of methylprednisolone (MP) in the treatment of simple forms of giant cell arteritis (GCA). (2) To analyze corticosteroid response, steroid related side effects, and GCA complications. METHODS: Patients received a 240 mg i.v. pulse of MP followed by 0.7 mg/kg/day oral prednisone (Group 1) or 0.7 mg/kg/day prednisone without an i.v. pulse (Group 2, controls), or a 240 mg i.v. pulse of MP followed by 0.5 mg/kg/day prednisone (Group 3). Corticosteroid dosage was reduced after normalization of 2 biological inflammatory variables to obtain half-dosage after 4 weeks in Groups 1 and 2 and 20 mg/day after 2 weeks in Group 3. Tapering was systematically attempted from the 6th month of treatment. RESULTS: One hundred sixty-four patients were included in the trial (1992-96). Cumulative doses of corticosteroids after one year were identical for all groups (p = 0.39). No significant differences were observed in the time required for normalization of C-reactive protein, corticosteroid resistance (13.5%), and corticosteroid related side effects (39% of patients; p = 0.37). Corticosteroid resistant patients received larger doses and showed a high risk of GCA related complications (p = 0.02). CONCLUSION: MP pulses have no significant longterm, corticosteroid sparing effects in the treatment of simple forms of GCA and should be limited to complicated forms. Moreover, corticosteroid resistance is a real risk factor for GCA complications.

Nonconvulsive status epilepticus: the role of morphine and its antagonist.

A 77-year-old woman with no history of epilepsy presented a probable nonconvulsive status epilepticus while receiving continuous intravenous morphine for back pain relating to vertebral metastasis of a malignant lymphoma. A generalized tonic-clonic seizure occurred a few minutes after injection of the morphine antagonist naloxone. No cerebral lesion was detected. This observation supports the notion of a possible pro-epileptogenic effect of opioid substances in association with metabolic and other toxic factors. Various hypotheses as to the complex actions of morphine and its antagonist in epileptogenesis are discussed.

Cervical cord and dorsal medullary infarction presenting with retro-orbital pain.

A 36-year-old woman experienced an excruciating right retro-orbital paroxysmal headache after a stroke of the anterior two-thirds of the right hemicord at the C1 level (anterior spinal artery territory) and the dorsal medulla (posterior spinal artery territory). A right vertebral artery dissection was demonstrated. This unusual infarct mimicked a cluster headache attack or paroxysmal hemicrania.

The Use of Thermodynamics for the Indirect Determination of Neutral Surfactants Activities in Mixtures of Potassium Polyvinyl Sulfate (PVSK), Dodecyltrimethylammonium Bromide (DTABr), and N-Dodecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate (SB12).

Mixtures of zwitterionic and cationic surfactants were studied in the presence of an anionic polyelectrolyte. We used N-dodecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate (SB12), dodecyltrimethyl ammonium bromide (DTA+Br-), and polyvinyl sulfate (potassium salt) (PVS-K+). The composition of the system was determined by measuring the activity of DTABr with an ion-selective electrode, and deducing the activity of SB12 from thermodynamic equations. This method provides information about the distribution of all species (activities of both surfactants and composition of the micelles), by experimental determination of only one quantity. SB12 affected the adsorption of DTABr onto PVSK. Copyright 1999 Academic Press.

Suspected hepatitis B vaccination related vasculitis.

Recombinant hepatitis B vaccination is widely used and severe side effects are rare. We describe 3 cases of vasculitis occurring after such immunization that are thought to have been vaccine induced. Vasculitides are now recognized as possible severe adverse side effects of immunization.

Constant chemical potential titration. Application to determination of nonionic surfactant concentrations.

Titration is most often associated with the idea of a stoichiometric reaction. Generally, it is not considered possible to titrate a compound against a reagent unless the titration reaction is near total and if the result is not a product of well-defined stoichiometry. In this work, we illustrate that accurate titration is possible with compounds and reagents that interact to form an association of undefined stoichiometry. Our model is the potentiometric titration of nonionic surfactant with cationic surfactant using a cationic surfactant-selective electrode. The result of this reaction is mixed micelles, the composition of which depends on the concentrations of the two surfactants in solution.

Construction and use of a detergent-sensitive electrode to measure dodecyl sulfate activity and binding.

We describe the construction and use of a dodecyl sulfate-sensitive electrode cell to measure the activity of the detergent in biological samples. The electrode is based on the incorporation of a cetyltrimethylammonium/dodecyl sulfate complex in a siloxane polymer membrane. The cell records changes in the activity of SDS from 10(-6) to 10(-5) M SDS up to the critical micellar concentration. In aqueous solutions the cell follows Nernst' law with an electrometric response which is not affected by protein per se, but is modified by supporting electrolytes like NaCl. We demonstrate by comparison with equilibrium dialysis that the electrode can be used both to detect the high-affinity binding sites of serum albumin for SDS and to follow cooperative binding of the detergent to serum albumin, ovalbumin, and beta-lactoglobulin in the concentration interval 10(-4)-10(-3) M of unbound SDS. We conclude that the electrode has properties which should enable its use to monitor changes in SDS activity during interaction with biological material. The electrode may also be used to measure the activity of other detergents which, like SDS, form a sparingly soluble complex with cetyltrimethylammonium bromide.