Photochemical activation of an azido manganese-monosubstituted keggin polyoxometalate: on the road to a Mn(V)-nitrido derivative.

The manganese(V)-nitrido polyoxometalate derivative [PW(11)O(39){Mn(V)N}](5-) has been synthesized by photochemical activation of the parent manganese(III)-azido derivative [PW(11)O(39)Mn(III)N(3)](5-). It was characterized by mass spectrometry, (31)P NMR, UV-vis, and IR spectroscopies. An electrochemistry study indicated that only the Mn(V) state was stable. The photoactivation of the manganese(III)-azido derivative proceeds through two competitive routes, yielding to the targeted product of photooxidation {Mn(V)N} or the undesirable product of photoreduction {Mn(II)L} (L = H(2)O, N(3)), depending on the photolysis conditions. A simplified photolysis mechanism involving two different excited states was proposed to account for the temperature and wavelength dependence.

[Proliferative retinal vasculitis and multiple sclerosis: a case report]. / Vascularites rétiniennes proliférantes et sclérose en plaques. A propos d'un cas.

INTRODUCTION: Retinal periphlebitis can precede the neurological effects of multiple sclerosis and reveal the disease. Although these occurrences of vasculitis are noted in 10% - 35% of multiple sclerosis patients, proliferative retinopathy is, on the contrary, an exceptional complication. CASE REPORT: We report the case of a 28-year-old woman who presented bilateral, proliferative, retinal vasculitis complicated with recurrent vitreous hemorrhages occurring with multiple sclerosis. Initially, there was a unilateral, central venous thrombosis in a particularly ischemic and proliferative form. After a neurological, biological and radiological check-up, the diagnosis of multiple sclerosis was pronounced and treatment with Interferon was started. A pan-retinal laser photocoagulation and vitrectomy with proliferative membrane peeling were performed. After a follow-up of 2.5 years, a bilateral epiretinal membrane on the macula with a chronic macular edema persisted, with visual acuity limited to 0.2 Parinaud 4 in the right eye and 0.5 Parinaud 2 in the left eye. DISCUSSION: This case shows that the diagnosis of multiple sclerosis must be established in cases of ischemic retinal vasculitis, especially as the literature does not seem to report a correlation between the retinal vascular affect and how far multiple sclerosis has progressed. Moreover, the visual prognosis of these proliferative lesions remains uncertain. CONCLUSION: Multiple sclerosis can be revealed initially, although exceptionally, by bilateral, proliferative and severe retinal vasculitis complicated with recurrent vitreous hemorrhages and tractional retinal detachment.

[Prediction of growth and dento-facial orthopedics. Importance and accuracy of superposition]. / Prévisions de croissance et orthopédie dento-faciale.

For a long time, the orthodontists have tried to predict the growth to come. They have atempted to know if there are relationships between height and facial growth and if a better knowledge of general development of child had an interest to their therapeutic decision. The author compare the methods of estimation and prediction of height and facial growth; and he thinks that these methods are not enough exact and safe and they have a little utility to the practionner. The author purpose to replace them by the search of radiologics signs which need anyone measurement and which the good prediction value is very adequate to the daily dento-facial orthopedic pratice.

Synthesis and photophysical and cation-binding properties of mono- and tetranaphthylcalix[4]arenes as highly sensitive and selective fluorescent sensors for sodium.

The syntheses and properties of two calixarene-based fluorescent molecular sensors are reported. These comprise tert-butylcalix[4]arene either with one appended fluorophore and three ester groups (Calix-AMN1). or with four appended fluorophores (Calix-AMN4). The fluorophore is 6-acyl-2-methoxynaphthalene (AMN), which contains an electron-donating substituent (methoxy group) conjugated to an electron-withdrawing substituent (carbonyl group); this allows photoinduced charge transfer (PCT) to occur upon excitation. The investigated fluoroionophores thus belong to the family of PCT fluorescent molecular sensors. In addition to the expected red shifts of the absorption and emission spectra upon cation binding, a drastic enhancement of the fluorescence quantum yield-in an "off- on" fashion comparable to that seen in photoinduced electron transfer (PET) molecular sensors-was observed. For Calix-AMN1. it increases from 10(-3) for the free ligand to 0.68 for the complex with Ca2+. This exceptional behaviour can be interpreted in terms of the relative locations of the npi* and pipi* levels, which depend on the charge density of the bound cation. For Calix-AMN4. in addition to the photophysical effects observed for Calix-AMN1, interactions between the chromophores by complexation with some cations have been found in the ground state (hypochromic effect) and in the excited state (excimer formation). Steady-state fluorescence anisotropy measurements for the system Na+ is included in Calix-AMN4, show a depolarization effect due to energy transfer (homotransfer) between the fluorophores. Regarding the complexing properties, a high selectivity for Na+ over K+, Li+, Ca2+ and Mg2+ was observed in ethanol and ethanol-water mixtures. The selectivity (Na+/other cations) expressed as the ratio of the stability constants was found to be more than 400.

[Proposal for a classification of Class II Division 1: contribution of Delaire's analysis]. / Proposition d'une classification des classes II division 1: contribution de l'analyse de Delaire.

Class II division 1 dental malocclusions are present in various forms depending on the site, direction and degree of discrepancy between the arches. The ability to recognize the origin of the malocclusion is essential to decide how, and when it is necessary to treat. In this study, the Delaire's analysis was performed for 111 individuals with a Class II division I malocclusion; a classification of these cases is proposed, according to the presence or the absence of a skeletal discrepancy. In 87% of the cases, a Class II division 1 dental malocclusion was associated with a Class II skeletal discrepancy (50% maxillary prognathism, 23.5% normal maxillary relationship and 13.5% maxillary retrognathism). The lines of the cranial base, the shape and size of the mandible varied considerably. In only 6% of cases, the dental malocclusion was associated with a skeletal Class I relationship, and in 7% of cases with a Class III relationship: it was often related to retruded mandibular teeth. It was shown that Class II division 1 dental malocclusions may result from differing causes: therefore, the identification of their etiology seems essential to provide the best possible treatment, at the right period in time.

[Vertical development of the face and cervical spine. Diagnostic and therapeutic significance in orthodontics and maxillofacial surgery]. / Développement vertical de la face et du rachis cervical. Intérêts diagnostique et thérapeutique en ODF et en chirurgie maxillo-faciale.

Vertical growth of the cervical spine, of the mandibula and the upper maxilla are normally anatomically and physiologically correlated. At a very early age the relationships are established between the cervical spine and the angle of the mandibula which is normally level with C2's antero-inferior angle. A parallelism can be noticed between the rhythms of the vertical growth of the cervical spine and the changes of the maxillary in relation to the skull. So relationships are gradually established between the palate level, the top of the odontoid, and the foramen magnum. These relationships are well objectivized on a lateral teleradiography by Delaire' analysis. Lateral teleradiography of the situation of the angle of the mandibula, in relation to the basis of the C2 body should be systematic. It provides much information concerning the growth potential of the condylar unit, and makes possible a differential diagnosis between true or false posterior vertical insufficiency (PVI) and true or false posterior vertical excess (PVE) and to recognize clinical types of skeletal class II and class III of vertical origin.

[The evolution of the lower jaw and the jaw joint, from reptiles to man]. / L'évolution de la mâchoire inférieure et de l'articulation des mâchoires, des reptiles à l'homme.

The evolution of the mandible shows two characteristic features: transformation of the angular, articular and square bones in reptiles into the tympanic bone, malleus and incus of the middle ear respectively; and specific volume expansion of the tooth-bearing bone which in mammals comprises the entire mandible. Posture, locomotion and mastication are the basic evolutionary factors which simultaneously provoked 1) a displacement of the temporal regions, 2) a transformation of the face lowering and widening the lower jaw and 3) an elongation of the sutures uniting the different bones in the reptile jaw bone, progressively leading to their separation and transversal orientation. These transformations were accentuated in the biped. Thus in man the temporomandibular joint is in a very lateral and elevated position near the mastoids. The mandibular condyls are elongated transversally with a medial cantilever. The medial part of the meniscus is drawn medially by the lateral pterygoid while the lateral part is drawn laterally by the temporal and masseter fibers. The ramus is oriented vertically and lies close to the cervical spine. The dental arches are displaced posteriorly on the bone and have lost their anterior abutment. The strongest occlusal forces are displaced to the posterior part of the arches and are transmitted vertically to the intra-articular meniscus. All these phenomena are termed extreme adaptations and the temporomandibular joint would (apparently) suffer if the evolution continued. The architectural features of temporomandibular joint overload can be deducted by comparison with the "ideal" architectural conditions for the craniofacial equilibrium.

Maxillary development revisited: relevance to the orthopaedic treatment of Class III malocclusions.

Normal development of the maxilla results not only from movements of its constituent skeletal units and bony apposition-resorption superficially, but also from the specific development of the antero-lateral regions. In Class III cases, correction of the skeletal dysmorphosis requires not only that the maxilla is in a correct position (in relation to the mandible) and that the correct occlusion is achieved, but also that there is good development of the exo-peri-premaxilla. This requires normalization of muscular posture (labio-mental, lingual, velo-pharyngeal) and of orofacial functions (nasal ventilation, swallowing, mastication). Postero-anterior traction using an orthopaedic mask can only accomplish part of the treatment of Class III. The action must always be complimented by other therapy aimed at correcting the underdevelopment of the antero-lateral regions. Facemask therapy is not only simple sagittal distraction, but is truly a method for treatment of Class III which is well understood and achieves excellent results. Taking into account the great diversity of anatomical forms of Class III malocclusion, it is not surprising that extra-oral postero-anterior traction gives widely varying results. The quality, however, depends principally on the method used. Orthodontists must not hesitate to call for the assistance of a surgeon each time the functional treatment is insufficient, particularly in cleft patients where the results depend more on surgical procedures, both primary and secondary, than on dentofacial orthopaedics.

Treatment of the craniofacial complications of Beckwith-Wiedemann syndrome.

Variable degrees of macroglossia have been noted in patients with Beckwith-Wiedemann syndrome. Past studies have shown that a major effect of the macroglossia is protrusion of dentoalveolar structures, resulting in an anterior open bite and a prognathic mandibular appearance secondary to an abnormally obtuse gonial angle and increased effective mandibular length. In our series of 11 Beckwith-Wiedemann syndrome patients we have observed that early correction of the macroglossia by means of partial glossectomy has resulted in decreased anterior open bite and mandibular prognathism as compared with patients managed conservatively.

Primary closure of the cleft alveolus: a functional approach.

The growth and development of the premaxilla in both normal and cleft lip and palate subjects is described and its relevance in surgery of the cleft alveolus discussed. Embryologically, the cleft alveolus results from failure of fusion of the median nasal and maxillary processes. Consequently, ossification centres in the premaxilla and maxilla cannot migrate and unite such that normal growth and development in the territory of the premaxillary-maxillary suture cannot occur. Functional repair of the cleft lip and soft palate encourages spontaneous alignment of the alveolar segments, facilitating the introduction of vascularized periosteum across the bony defect by gingivoperiosteoplasty. Early reconstruction in the region of the premaxillary-maxillary suture encourages a more normal development of the alveolus, particularly in the bilateral cleft subject.

Histochemical analysis of cleft palate muscle.

Research has clarified the abnormal insertions and orientations of the involved musculature in cleft palate. However, little is known about the physiologic aspects of these muscles, specifically from a histochemical perspective. In this study, 30 muscle specimens were removed from the palatal cleft margin in patients undergoing primary palatoplasty. Nine patients had combined cleft lip and palate deformity, and seven had an isolated cleft palate. Biopsies were taken from the area of the musculus uvulus in all specimens and examined by histochemical techniques. The percentage of type 1 and type 2 fibers was different in isolated cleft palate as compared with cleft lip and palate specimens, being, respectively, 56.7 percent type 1 and 43.3 percent type 2 and 62.0 percent type 1 and 38.0 percent type 2 fibers. This is the opposite ratio from other facial muscles but is in line with the literature regarding normal palatal muscle. Isolated cleft palate muscle fibers also were minimally decreased in diameter as compared with normal facial muscle. Fiber diameters of the combined cleft lip and palate muscles were severely decreased in size compared with those muscles found in the cleft lip. Abnormal mitochondrial accumulations also were found in cleft lip and palate muscle specimens but not in isolated cleft palate muscle specimens. We consider the decrease in muscle diameter found in isolated cleft palate to be secondary to functional atrophy, while that in the cleft lip and palate specimens is secondary to a primary hypoplasia together with a functional atrophy.(ABSTRACT TRUNCATED AT 250 WORDS)

Functional primary closure of cleft lip.

A technique of primary closure of the cleft lip is described. It is based on a complete understanding of the anatomy of the entire facial musculature such that it can be restored to normality and so encourage normal function and development.

Primary closure of cleft palate: a functional approach.

The role of the different zones of palatal mucosa in maxillary growth are considered and their relevance in surgery of cleft palate discussed. A method of cleft palate repair is described, based on a functional repair of the soft palate, followed by later closure of the hard palate taking into account the anatomy and physiology of the palatal mucosa.

Clinical observations of cleft lip and palate.

In surgical management of cleft lip and palate, appreciation of the special anatomy and physiology of the human premaxilla is more important than the question of whether it is a separate bone. To take advantage of the potential of the premaxilla, both primary and secondary surgical procedures must strive to establish a nearly normal medial septal system and nasolabial musculature. To complement accurate muscle surgery of the lip and soft palate, the characteristics and functions of the mucoperiosteum that covers the palate must be respected. The quality of subsequent facial growth can be monitored with the architectural craniofacial cephalometric analysis. By adopting a physiologic approach to cephalometrics, the clinician can avoid some common errors of interpretation.

Facial balance in cleft lip and palate. I. Normal development and cleft palate.

A full understanding of balanced facial growth, based on a complete knowledge of the anatomy and physiology of the region, is essential if cleft lip and palate is to be treated successfully. The cleft abnormality is the cause of underdevelopment and subsequent loss of function. Cleft surgery must aim to restore normal anatomy and physiology with emphasis on muscle reconstruction of the lip and soft palate if normal facial development is to be achieved.

Facial balance in cleft lip and palate. II. Cleft lip and palate and secondary deformities.

The cleft abnormality is the cause of underdevelopment and subsequent loss of function. Primary cleft surgery and surgery to correct the secondary deformities of previous non-functional repair should aim to restore normal anatomy and physiology, with an emphasis on muscle reconstruction of the lip and soft palate if normal facial development is to be encouraged.

Macrostomia, ectropion, atrophic skin, hypertrichosis: another observation.

We report on a boy with bilateral ectropion, ocular hypertelorism, bulbous nose, macrostomia with thin lips, abnormal ears, hypertrichosis of the forehead, neck and back, atrophic skin with hypoplastic nipples. Cause and inheritance are unknown.

[Medicolegal considerations. Apropos of tooth germ transplantation between 2 twins]. / Considérations médico-légales. A propos de la transplantation de germes dentaires entre deux jumeaux.

With regard to medicolegal problems, semantics are of considerable importance: indeed, depending on whether we call grafting or transplantation of an organ the operation that takes a living organ to reimplant it in the same person or the operation that takes a living organ from a donor to reimplant it in a recipient, the issues raised are completely different. The transposition of a dental organ does not raise any particular problems apart from the technical requirements to be met; there is no special problem of prevention or ethics to be taken into consideration. The problem is a completely different one when it means taking a living organ from a living or dead subject and reimplanting it in another subject. All measures decreed from the point of view of law and regulations that are dictated by considerations of prevention and ethics must then be strictly applied.