Osteonecrosis Mandibular Extended to Bisphosphonates: A Very Rare Extensive Case.

After the first report of bisphosphonate-related osteonecrosis of the jaw (BRONJ) in 2003, it has increased significantly since then. We report a very rare extensive case never seen before in our experience of bone exposure with necrosis reaching the mandibular inferior border. Although the treatment modalities are not yet established, most researchers have recommended conservative approaches. The surgery was to be as conservative as possible, with a resection of the mandibular range followed by reconstruction using titanium plate with space maintainer. The authors would like to share their approach, management, and awareness.

[Craniofacial adulthood rhabdomyosarcoma: a case with poor prognosis]. / Rhabdomyosarcome cranio-facial de l'adulte: un cas de mauvais pronostic.

Rhabdomyosarcoma is the more frequent mesenchymal tumor in children and in adolescents. It accounts for 60 -70% of mesenchymal tumors and approximately 5% of all solid tumors occurring at these ages. Almost half of rhabdomyosarcomas occur in the head and the neck. We report the case of a 20-year old patient with a new histological, aggressive temporo-parietal rhabdomyosarcoma.

Sarcomatoid Carcinoma of the Maxilla: A Case Report with Literature Review.

Sarcomatoid carcinoma is a very rare malignant and aggressive tumor that can involve the maxillary sinus. We report the case of a 46 y/o male who presented a tumor of the right maxillary sinus with extension to the right nasal cavity. The diagnosis of sarcomatoid carcinoma was set by histology and immunohistochemistry. The patient received concomitant cisplatin based chemoradiotherapy with no response after 3 months of treatment. He died 6 months later. Through the present case and the review of literature we discuss all aspects of this entity: clinical presentation, differential diagnoses, pathology, treatment and prognosis.

Hyperparathyroidism-jaw tumour syndrome detected by aggressive generalized osteitis fibrosa cystica.

Severe hyperparathyroidism can affect bone metabolism and be in the origine of multiple brown tumours (generalized osteitis fibrosa cystica). When associated with fibro-ossifying tumours of the jaw, it realizes a rare genetic syndrome referred as Hyperparathyroidism-jaw tumour HPT-JT. We report the case of a patient we treated for HPT-JT, and literature review.

Bcl-2 overexpression in type II epithelial cells does not prevent hyperoxia-induced acute lung injury in mice.

Bcl-2 is an anti-apoptotic molecule preventing oxidative stress damage and cell death. We have previously shown that Bcl-2 is able to prevent hyperoxia-induced cell death when overexpressed in a murine fibrosarcoma cell line L929. We hypothesized that its specific overexpression in pulmonary epithelial type II cells could prevent hyperoxia-induced lung injury by protecting the epithelial side of the alveolo-capillary barrier. In the present work, we first showed that in vitro Bcl-2 can rescue murine pulmonary epithelial cells (MLE12) from oxygen-induced cell apoptosis, as shown by analysis of LDH release, annexin V/propidium staining, and caspase-3 activity. We then generated transgenic mice overexpressing specifically Bcl-2 in lung epithelial type II cells under surfactant protein C (SP-C) promoter (Tg-Bcl-2) and exposed them to hyperoxia. Bcl-2 did not hinder hyperoxia-induced mitochondria and DNA oxidative damage of type II cell in vivo. Accordingly, lung damage was identical in both Tg-Bcl-2 and littermate mice strains, as measured by lung weight, bronchoalveolar lavage, and protein content. Nevertheless, we observed a significant lower number of TUNEL-positive cells in type II cells isolated from Tg-Bcl-2 mice exposed to hyperoxia compared with cells isolated from littermate mice. In summary, these results show that although Bcl-2 overexpression is able to prevent hyperoxia-induced cell death at single cell level in vitro and ex vivo, it is not sufficient to prevent cell death of parenchymal cells and to protect the lung from acute damage in mice.

Oncogenic association of the Cbp/PAG adaptor protein with the Lyn tyrosine kinase in human B-NHL rafts.

B-non-Hodgkin lymphomas (B-NHLs) use a raft-associated signalosome made of the constitutively active Lyn kinase, the tyrosine phosphorylated Cbp/PAG adaptor, and tyrosine phosphorylated STAT3 transcription factor. No such "signalosome" is found in rafts of ALK(+) T lymphoma and Hodgkin-derived cell lines, despite similar Cbp/PAG, Lyn, and STAT3 expression and similar amounts of raft sphingolipids. Stable association of the signalosome with B-NHL rafts requires (1) a Lyn kinase (auto)phosphorylated in its regulatory and active site tyrosines, (2) a Cbp/PAG adaptor phosphorylated at tyrosine 317 and bound to Lyn SH2 via phosphotyrosine 299 and neighboring residues, and (3) a tyrosine phosphorylated STAT3 linked via SH2 to the regulatory, C-terminal tyrosine of Lyn. No Csk appears to be part of this B-NHL signalosome. An oncogenic role for Lyn was shown after exposure of B-NHL lines to Lyn inhibitors that prevented Lyn and Cbp/PAG phosphorylation, dissociated the signalosome from rafts, and eventually induced death. Cell death followed decreases in Lyn or Cbp/PAG expression levels in one mantle cell lymphoma line, but not in a Hodgkin-derived one. The Lyn-Cbp/PAG signalosome appears to control proliferation and survival in most B-NHLs and constitutes a therapeutic target in B-NHL cells that exhibit oncogenic "addiction" to the Lyn kinase.

The frontal sinus: a culprit or a victim? A review of 40 cases.

PURPOSE: Frontal sinus fractures represent 2-12% of facial trauma. The purpose of this article is to discuss proper management of these fractures and to evaluate the indications for treatment, the complications and the morphologic results of surgery. MATERIAL AND METHODS: The records of 40 patients admitted to this department with a frontal sinus fracture were reviewed. Sex, age, the circumstances of injury, the imaging techniques, fracture patterns, associated injuries, length of hospital stay, surgical approaches and the complications were analysed. The operations included 3 main options: cranialization, obliteration or reconstruction of the frontal sinus. RESULTS: There were 32 men and 8 women (average 34 years). The most common cause of injury was motor vehicle accidents. Conventional radiography of the face was complemented by computed tomography and 3D reconstructions. Isolated anterior table fractures were found in 72.5% and combined anterior/posterior table fractures in 27.5% of the cases. The treatment was surgical for 70% of the patients; the average length of hospitalization was 1 week. Postoperative complications were: 1 brain abscess, 2 cases of frontal sinusitis and 2 cases of chronic headache. CONCLUSION: Long-term complications in frontal sinus fractures are intracranial infection, sinusitis and forehead defects. To avoid these it was decided to treat all displaced fractures surgically in displaced anterior table fractures the sinus was obliterated with cancellous bone and in displaced posterior table fractures the sinus was cranialized.

A novel class of secA alleles that exert a signal-sequence-dependent effect on protein export in Escherichia coli.

The murine plasminogen activator inhibitor 2 (PAI2) signal sequence inefficiently promotes the export of E. coli alkaline phosphatase (AP). High-level expression of PAI2::AP chimeric proteins from the arabinose P(BAD) promoter is toxic and confers an Ara(S) phenotype. Most Ara(R) suppressors map to secA, as determined by sequencing 21 independent alleles. Mutations occur throughout the gene, including both nucleotide binding domains (NBDI and NBDII) and the putative signal sequence binding domain (SSBD). Using malE and phoA signal sequence mutants, we showed that the vast majority of these secA suppressors exhibit weak Sec phenotypes. Eight of these secA mutations were further characterized in detail. Phenotypically, these eight suppressors can be divided into three groups, each localized to one domain of SecA. Most mutations allow near-normal levels of wild-type preprotein export, but they enhance the secretion defect conferred by signal sequence mutations. Interestingly, one group exerts a selective effect on the export of PAI2::AP when compared to that of AP. In conclusion, this novel class of secA mutations, selected as suppressors of a toxic signal sequence, differs from the classical secA (prlD) mutations, selected as suppressors of defective signal sequences, although both types of mutations affect signal sequence recognition.