Potential effects of a low-molecular-weight fucoidan extracted from brown algae on bone biomaterial osteoconductive properties.

In this work, we first tested the influence of low-molecular-weight (LMW) fucoidan extracted from pheophicae cell wall on bidimensional cultured normal human osteoblasts' behaviors. Second, by impregnation procedure with LMW fucoidan of bone biomaterial (Lubboc), we explored in this bone extracellular matrix context its capabilities to support human osteoblastic behavior in 3D culture. In bidimensionnal cultures, we evidenced that LMW fucoidan promotes human osteoblast proliferation and collagen type I expression and favors precocious alkaline phosphatase activity. Furthermore, with LMW fucoidan, von Kossa's staining was positive at 30 days and positive only at 45 days in the absence of LMW fucoidan. In our three-dimensional culture models with the biomaterial pretreated with LMW fucoidan, osteoblasts promptly overgrew the pretreated biomaterial. We also evidenced that osteoblasts increased proliferation with pretreated biomaterial when compared with untreated biomaterial. Osteoblasts secreted osteocalcin and expressed BMP2 receptor on control material as well as with LMW fucoidan impregnated biomaterial. In conclusion, in our experimental conditions, LMW fucoidan stimulated expression of osteoblastic markers differentiation such as alkaline phosphatase activity, collagen type I expression, and mineral deposition; furthermore, cell proliferation was favored. These findings suggest that fucoidan could be clinically useful for bone regeneration and bone substitute design.

[Chronic hepatitis B virus and hepatitis C virus infections. Hidtology-classification--examination]. / Chronische Hepatitis-B-Virus- und Hepatitis-C-Virus-Infektion. Histologie--Klassifikation--Begutachtung.

Clinicians disagree over the need to perform liver biopsy in chronic infections with hepatitis B and C viruses, with opinions ranging from "useless" to "conditionally advisable" to "absolutely necessary." The frequency of liver biopsies has generally been declining, which entails decreased practical knowledge in the morphological examination of liver biopsies. As a result certain basic considerations must occasionally reemphasized.

[Pneumosinus dilatans. Long-term result of modelling osteoplasties]. / Pneumosinus dilatans. Résultat à long terme des ostéoplasties modelantes.

Pneumosinus dilatans is a rare disease characterized by an evolutive hyperpneumatization of the sinuses. The frontal sinus is most often involved, but any other sinus of the face can be affected. Three cases of pneumosinus dilatans, including two in the frontal sinus and one in the maxillary sinus, are reported. Modelling osteoplasty without drainage of the sinus was performed in all three cases and yielded satisfactory and stable results with a minimal period of observation of 5 years. The long-term effectiveness of modelling osteoplasty must be taken into account to study the physiopathology of pneumosinus dilatans. The most likely etiopathogenetic hypothesis is a disorder in the local growth of the sinus.

[Value of preserving mandibular continuity in transmandibular bucco-pharyngectomy. Apropos of 11 cases]. / Intérêt de la conservation de la continuité mandibulaire dans les bucco-pharyngectomies transmandibulaires. A propos de 11 observations.

84 transmandibular bucco-pharyngectomies were carried out over 6 years between 1983 and 1988. Eleven, i.e. 13%, were performed with preservation of mandibular continuity. Histological examination of resected bone fragments did not demonstrate any bony invasion in 65 cases; in contrast, in 8 cases, extension of the tumour to involve bone was likely due to the topography of the tumour and the results of pre-operative X-ray examination.

[Rhinoplasty with the external approach. Report of 23 cases]. / La rhinoplastie par voie externe. A propos de 23 cas.

23 external rhinoplasties were carried out over a 4-year period between 1986 and 1989. In 19 cases, they related to major malformations or traumatic sequelae requiring a spindle or columella bone graft. In 14 out of these 19 cases, an iliac graft was used. This approach requires a specific technique but it allows an accurate dissection of all the nose structures and grafting under excellent conditions.

[Plexiform tumor of the uterus]. / Plexiformer Tumor des Uterus.

Uterine plexiform tumors are morphologically distinctive lesions. Usually they are incidental microscopic findings in hysterectomy specimens that have been removed for other reasons. The rarity and the complex histomorphology of the small intramyometrial tumors may cause confusion in the diagnosis. In the reported case immunohistochemistry was performed. The results point to the disputed histogenesis that plexiform tumors are of smooth muscle origin. All plexiform tumors reported in the literature showed a benign clinical course; also in cases with intravascular extension as in intravascular leiomyomatosis.

[Malformation of the facial canal, meningitis and cerebrospinal otorrhea]. / Malformations du canal facial, méningite et otorrhée cérébro-spinale.

CSF fistulas into the middle ear due to labyrinthine or tegmental anomalies are well known. They predispose to recurrent meningitis if they do not receive appropriate surgical treatment. CSF fistulas due to facial canal anomalies are extremely rare and predispose to the same risk of meningitis. The case reported enables a comparison to be made with the three other cases of the same form of anomaly found in the literature, and the diagnostic and therapeutic difficulties are also discussed.

The diagnostic significance of periportal hepatic necrosis and inflammation.

In this review the several types of cell damage and cell death which may be found in liver biopsy specimens are defined. We describe the different processes which occur at the portal/parenchymal or septal/parenchymal interface, viz. periportal spillover, periportal hepatitis, classic or lymphocytic piecemeal necrosis and biliary piecemeal necrosis. The diagnostic implications of these lesions in relation to the clinicopathological diagnosis and prognosis in various liver diseases are discussed.

[Perilymphatic fistula. Diagnostic and therapeutic difficulties]. / Fistules péri-lympathiques. Difficultés diagnostiques et thérapeutiques.

The symptoms and signs of perilymphatic fistulae (PLF) are very varied and frequently misleading. The operative demonstration of a perilymph leak is not always obvious and the therapeutic results are sometimes disappointing. The study of 26 cases demonstrates certain concepts concerning the diagnostic and therapeutic difficulties. Any atypical cochleovestibular symptoms, particularly occurring in a traumatic context, should suggest the possibility of PLF. Exploratory surgery must be performed according to a rigorous protocol in order to demonstrate the fistula. Search for a fenestra ovalis sign due to pressure on the membrane of the fenestra rotunda may help to reveal a lesion of the annular ligament. Simple filling of the breach is not always effective, especially at the level of the stapes. Stapedectomy frequently constitutes the best solution for fistulae of the fenestra ovalis.

Hepatoprotection by malotilate against carbon tetrachloride-alcohol-induced liver fibrosis.

Subchronic treatment of male rats with carbon tetrachloride (CCl4, twice weekly 0.2 ml/kg p.o.) and feeding a 5% alcohol solution instead of drinking water led to a nearly complete liver cirrhosis in all animals within 4 weeks. This was also documented by a three fold increase in hepatic total hydroxyproline content. Steatosis was quantified by enhanced liver triglyceride concentrations and acute necroses by increments of serum enzyme activities (GPT, SDH). Daily oral treatment with malotilate (100 mg/kg) totally prevented the development of liver cirrhosis, hepatic hydroxyproline accumulation and increases in serum enzyme activities induced by CCl4-alcohol. In cianidanol-treated rats (100 mg/kg p.o.) only portoseptal fibrosis was seen, however hydroxyproline and triglyceride accumulation as well as enhanced serum enzyme activities were not suppressed. D-penicillamine (300 mg/kg p.o.) and colchicine (50 micrograms/kg i.p.) failed to protect rats against CCl4-alcohol induced fibrosis, necrosis and steatosis in this model.

Effect of subchronic cholestasis on microsomal mixed-function oxidases and the glutathione-conjugating enzyme system in rat liver.

Bile duct ligation in male rats for two weeks led to a marked increase in both serum sorbitol dehydrogenase activity and serum bile acid concentration indicating cholestatic liver injury. Furthermore, a rise in the hepatic hydroxyproline level indicating collagen accumulation was observed. As a consequence of these alterations, the hepatic microsomal mixed-function oxidase system was impaired as evidenced by a decrease in cytochrome P-450 content and in the activities of NADPH-cytochrome c reductase and aminopyrine-demethylase. While the hepatic glutathione content remained unaffected, the cytosolic GSH S-transferase activity was clearly suppressed due to subchronic cholestasis.

[Conduction deafness and collapse of the auditory meatus. Value and limitations of the stapedial reflex in conduction deafness]. / Surdité de transmission et collapsus du meat auditif. Intérêt et limites du réflexe stapédien dans les surdités de transmission.

Collapse of the auditory meatus constitutes an audiometric trap provoking a false transmission deafness. It can also permanently affect audition, whether it be primary in origin or post-mastoidectomy. The association of conservation of the stapedial reflex and transmission deafness is noticed immediately, but this is in fact compatible with an interruption in the chain by incus luxation. These notions must be known in order to avoid operation in false transmission deafness, and inversely to decide when to explore the cavity in certain post-mastoidectomy sequelae with meatal collapse.