Transoral robotic surgery for obstructive sleep apnea syndrome: Principles and technique

Objective:The present study is a review of transoral robotic surgery (TORS) for the treatment of obstructive sleep apnea-hypopnea syndrome (OSAHS).Methods:The review presents the experience of the robotic center that developed the technique with regards to patient selection,surgical method,and post-operative care.In addition,the review provides results of a systematic review and meta-analysis of the complications and clinical outcomes of TORS when applied in the management of OSAHS.Results:The rate of success,defined as 50％ reduction of pre-operative AHI and an overall AHI ＜20 events/h,is achieved in up to 76.6％ of patients with a range between 53.8％ and 83.3％.The safety of this approach is reasonable as the main complication (bleeding) affected 4.2％ of patients (range 4.2％-5.3％).However,transient dysphagia (7.2％;range 5％-14％) does compromise the quality of life and must be discussed with patients preoperatively.Conclusions:TORS for the treatment of OSAHS appears to be a promising and safe procedure for patients seeking an alternative to traditional therapy.Appropriate patient selection remains an important consideration for successful implementation of this novel surgical approach requiring further research.

Three-dimensional collagen-based scaffold model to study the microenvironment and drug-resistance mechanisms of oropharyngeal squamous cell carcinomas

Objective:Squamous cell carcinoma(SCC)represents the most common histotype of all head and neck malignancies and includes oropharyngeal squamous cell carcinoma(OSCC),a tumor associated with different clinical outcomes and linked to human papilloma virus(HPV)status.Translational research has few available in vitro models with which to study the different pathophysiological behavior of OSCCs.The present study proposes a 3-dimensional(3 D)biomimetic collagen-based scaffold to mimic the tumor microenvironment and the crosstalk between the extracellular matrix(ECM)and cancer cells.Methods:We compared the phenotypic and genetic features of HPV-positive and HPV-negative OSCC cell lines cultured on common monolayer supports and on scaffolds.We also explored cancer cell adaptation to the 3 D microenvironment and its impact on the efficacy of drugs tested on cell lines and primary cultures.Results:HPV-positive and HPV-negative cell lines were successfully grown in the 3 D model and displayed different collagen fiber organization.The 3 D cultures induced an increased expression of markers related to epithelial–mesenchymal transition(EMT)and to matrix interactions and showed different migration behavior,as confirmed by zebrafish embryo xenografts.The expression of hypoxia-inducible factor 1α(1α)and glycolysis markers were indicative of the development of a hypoxic microenvironment inside the scaffold area.Furthermore,the 3 D cultures activated drug-resistance signaling pathways in both cell lines and primary cultures.Conclusions:Our results suggest that collagen-based scaffolds could be a suitable model for the reproduction of the pathophysiological features of OSCCs.Moreover,3 D architecture appears capable of inducing drug-resistance processes that can be studied to better our understanding of the different clinical outcomes of HPV-positive and HPV-negative patients with OSCCs.

Acute anemia after dental extraction:A case report

A patient treated with a vitamin K antagonist (VKA) since the implantation of two mechanical heart valves developed acute anemia after the extraction of a tooth. This case report and data in the literature indicate a need for specific measures before, during, and after oral surgery in patients taking anticoagulant therapy: 1) the bleeding risk should be evaluated before the procedure. The INR should be measured routinely, 2) the procedure should be scheduled early in the week to allow an evaluation at the fibrinolysis peak, i.e., 48 to 72 hours after surgery, which is the time of greatest risk of delayed bleeding, 3) the surgical procedure should be appropriate for the elevated bleeding risk, 4) postoperative monitoring is of the most importance, as bleeding is usually delayed in patients on VKA therapy, 5) when poor treatment adherence is expected, day-hospital admission is useful to ensure that the postoperative protocol is implemented properly and to detect early bleeding. The treatment of post-extraction acute anemia includes local hemostasis protocol with the revision of the socket followed by red-blood-cell pack transfusion. A daily fluindione dosage control, and a normal hemoglobin level will allow the patient to leave the hospital.

Gene-activated matrix harboring a miR20a-expressing plasmid promotes rat cranial bone augmentation

Gene-activated matrix(GAM)has a potential usefulness in bone engineering as an alternate strategy for the lasting release of osteogenic proteins but efficient methods to generate non-viral GAM remain to be established.In this study,we investigated whether an atelocollagen-based GAM containing naked-plasmid(p)DNAs encoding microRNA(miR)20a,which may promote osteogenesis in vivo via multiple pathways associated with the osteogenic differentiation of mesenchymal stem/progenitor cells(MSCs),facilitates rat cranial bone augmentation.First,we confirmed the osteoblastic differentiation functions of generated pDNA encoding miR20a(pmiR20a)in vitro,and its transfection regulated the expression of several of target genes,such as Bambi1 and PPARc,in rat bone marrow MSCs and induced the increased expression of BMP4.Then,when GAMs fabricated by mixing 100 ll of 2%bovine atelocollagen,20mg b-TCP granules and 0.5mg(3.3 lg/ll)AcGFP plasmid-vectors encoding miR20a were transplanted to rat cranial bone surface,the promoted vertical bone augmentation was clearly recognized up to 8 weeks after transplantation,as were upregulation of VEGFs and BMP4 expressions at the early stages of transplantation.Thus,GAM-based miR delivery may provide an alternative non-viral approach by improving transgene efficacy via a small sequence that can regulate the multiple pathways.