Pair-rule genes cooperate to activate en stripe 15 and refine its margins during germ band elongation in the D. melanogaster embryo.

Patterns of gene expression have been well documented during embryogenesis for the Drosophila melanogaster trunk segments. The same is not the case for the terminal segments. Here, gene expression patterns are followed during embryogenesis in the caudal segments (A8-A10 and the anal plate), with special attention paid to the novel regulation of engrailed (en). Chosen for this study are the pair-rule genes even-skipped (eve), fushi tarazu (ftz), runt (run), hairy (h), paired (prd) and odd-skipped (odd), and the segment polarity gene (en). The results demonstrate a progressive and coupled translocation of gene expression distally for all genes studied, suggesting that the most posterior segments are determined later than trunk segments.

Subperiosteal subtemporal approach: technique and applications.

The authors describe a craniofacial surgical approach that they have used since 1987. Based on existing anatomical continuity between the subtemporal plane and the cranial periosteum, it consists of a direct subperiosteal subtemporal cleavage. Preservation of continuity between the muscle and the periosteum allows the operator to return the temporalis muscle to a normal position at the end of the operation when the scalp is sutured. This approach avoids superficial cleaving of the temporalis muscle or section and reinsertion to the fronto-orbital rim. It also allows access to the upper third of the face without jeopardizing the frontal ramus of the facial nerve.

The effect of the type of colloid on the efficacy of hypertonic saline colloid mixtures in hemorrhagic shock: dextran versus hydroxyethyl starch.

Colloids increase and prolong the efficacy of hypertonic saline solutions in hemorrhagic shock. We compared the efficacy of dextran 60 and hydroxyethyl starch (HES) 200,000/0.5 at iso-oncotic concentrations of 6.5 or 6% in a 7.5% NaCI solution. Thirty-two rabbits were bled to maintain a mean arterial pressure at 35 mmHg. Twenty-five percent of the shed blood volume was replaced after 40 min by bolus infusion either with hypertonic dextran (HS-DEX) (n = 16) or with hypertonic hydroxyethyl starch (HS-HES) (n = 16). The animals were then observed for a 120-min period. In both groups immediate and complete restoration of cardiovascular function was achieved in up to 30 min and adequate restoration maintained for 60 min after infusion. During the subsequent 60 min signs of insufficient oxygen supply indicated the recurrence of near shock levels. Greater stability of hemodynamic efficacy was observed when dextran was added to hypertonic saline. The decrease in mean arterial pressure was lower in the dextran group (P < 0.05). The subsequent increase in avDO2 (v. cava sup.) was approximately 50% lower with dextran (1 ml/dl compared to 1.8 ml/dl); (P < 0.05). These differences occurred primarily within the initial 15 min although the differences in mean arterial pressure were recorded only after 30-60 min. A 50% reduction in lactate levels (1.1 compared to 2.0 mmol; P < 0.05) in immediate response to reinfusion indicates an increased lactate absorption and thus improved perfusion of poorly perfused tissue in the dextran group. A further, important difference may be due to the different effects on the microcirculation. As evidenced by a decline in the end-expiratory arterial CO2 gradient, dextran effected a significant (P < 0.01) improvement in decreased pulmonary CO2 emission during shock. This indicates a greater rise of blood flow in poorly perfused, ventilated pulmonary areas. In summary, in our model dextran appeared to be the superior colloid compared to HES, particularly during the first hour after initiation of treatment, although direct proof of an improved long term outcome has not been demonstrated.

[Orbito-palpebral prosthesis retained by intraosseous implants]. / Prothèse orbito-palpébrale fixée par implants endo-osseux.

The use of intraosseous implants, whose tolerance is continually improving, constitutes an important progress in the field of prosthetic rehabilitation. In particular, titanium implants largely resolve the problem of retention of craniofacial prostheses. Our experience, based on that of Swedish authors concerning the extra-oral use of intraosseous implants, was sufficiently convincing to adopt this effective technique in our patients candidates for prosthetic rehabilitation. The case of a patient rehabilitated by means of an orbito-palpebral prosthesis is presented after a brief biomechanical review and presentation of the technique. Our results, although preliminary, are very encouraging in terms of the technical aspects as well as patient comfort. A further study could reinforce our decision.

[Recent developments in esthetic rhinoplasty]. / Développements récents dans la rhinoplastie esthétique.

Over the last two decades, the concepts of cosmetic rhinoplasty have advanced, essentially due to the influence of J. Sheen. The importance of the anatomy of osteocartilaginous structures, their dynamic role, and the repercussions of their modification on the external shape has led to a more conservative surgery. Innovations have essentially concerned nose tip surgery and cartilage grafts. The revival of external approach and its popularity constituted the second major development; this can be explained by the direct, visualisation of cartilaginous structures and by the desire or necessity to preserve or reconstruct these structures. The indications for cartilage grafts have become more frequent and graft techniques have been developed and refined. The difficulties encountered in the use of autologous grafts have favoured the development of many new implants. Parietal cranial grafts occupy an increasingly important place in the indications for nasal bone grafts.

Heterotopic neuroglial tissue of the face. Report of six cases and review of the literature.

We report six cases of heterotopic neuroglial tissue of the face. All cases appeared at birth with a laterofacial mass and, in most cases, a respiratory disorder. The initial diagnosis has frequently been lymphangioma. But the rapidly growing character of the mass with resistance to high dose corticoid therapy, the fluid aspect at computerized tomography imaging with no connection to the central nervous system, and the presence of cerebrospinal fluid at the needle puncture were the most helpful features in narrowing the differential diagnoses. Patients were treated by surgical removal of the mass. The pathologic study showed the presence of neuroglial tissue. The management of the patients is discussed. The thirteen previous cases reported in the literature and our six cases lead to a discussion on the embryologic origin of this rare entity--the cephalic neural crest.

[Aneurysmal cyst of the mandible: radiologic approach and therapy of this benign tumor]. / Kyste anévrismal de la mandibule: approche radiologique et thérapeutique de cette tumeur bénigne.

The authors present a case of mandibular aneurysmal bone cyst with emphasis on the radiological aspects. The presence of fluid-fluid levels on CT and MR images is highly suggestive of ABC especially where there is no evidence of solid lesion. These findings help narrow differential diagnoses before making a therapeutic decision.

[Temporomandibular ankylosis in children: apropos of 30 cases]. / Ankylose temporo-mandibulaire de l'enfant: à propos de 30 observations.

Temporomandibular joint ankylosis in children is responsible for facial growth disorder. A series of 30 cases is presented. Patients are aged from 3 months to 15 years (mean = 7.6 years). Infection is the most frequent etiology. Recurrence rate is higher in bilateral cases. Early surgical treatment followed by meconotherapy led us to 93% satisfactory results.

Comparative studies with Fluosol, Dextran, their mixture, or autologous blood in experimental hypovolemic shock.

In 42 rabbits blood pressure was held at 40 mmHg/15 min. Various treatments resulted in equal recovery from shock in 4 groups. There is, however, some evidence that: (1) Dextran 40 was superior regarding microcirculation; (2) Fluosol added more oxygen to the tissues; and (3) a combined treatment showed both effects.

[Pseudo-tumoral osteitis of the mandible in children]. / Ostéite pseudo-tumorale de la mandibule chez l'enfant.

Infections with a dental origin are sometimes complicated with chronic osteoperiostitis and are seen clinically as a pseudotumour. We present a case together with the diagnostic and therapeutic approaches.

[Orbito-palpebral prosthesis and intraosseous implants]. / Epithèse orbito-palpébrales et implants intra-osseux.

Authors report their experience of the use of intraosseous implants for orbito-palpebral prosthesis. Principles are reminded and advantages discussed.