Features and Strategies in the Management of Choanal Atresia: A 6-Year Retrospective Analysis.

INTRODUCTION: Choanal atresia although rare, is the most common inborn nasal deformity and an important cause of newborn airway obstruction. This study aims to describe a single-center experience in the management of choanal atresia and emphasize the ambiguous issues regarding its surgical repair. PATIENTS AND METHODS: The authors retrospectively analyzed the treatment strategy of 18 patients with choanal atresia and their outcomes during the follow-up period. RESULTS: Bilateral choanal atresia was diagnosed in 9 patients, 6 of those had mixed bony-membranous type (67% versus 33% who had pure bony type). Almost half of the 18 patients had a mixed bony-membranous type of atresia (56%). Interestingly, 89% of patients with bilateral atresia underwent transnasal endoscopic repair with stenting, compared to 44% of those with unilateral atresia (P = 0.04). A trend to preference of stent procedure in patients with bony type was also observed, in comparison with mixed bony-membranous type (89% versus 50%, P = 0.09). No significant difference in the need for revision treatment was noticed among the two treatment groups. CONCLUSIONS: Both in our data and literature there is no clear supremacy of stenting. Considering the high incidence of re-stenosis, all patients should be under close follow up for a long-term period. Inevitably, further investigation is necessary to establish an ideal surgical procedure.

Primary Lymphangioma of the Palatine Tonsil in a 9-Year-Old Boy: A Case Presentation and Literature Review.

Primary lymphangiomas or lymphangiomatous polyps of the palatine tonsil are rare benign lesions that are described infrequently in the literature. The majority of the published cases concern adults. We report a case of a lymphangiomatous lesion of the right palatine tonsil of a 9-year-old boy. Our clinical suspicion was confirmed by the histological examination after tonsillectomy and the diagnosis of primary lymphangioma of the tonsil was made. In this case we discuss the clinical and histopathological features of this lesion and present a short review of the current literature.

A low cost-video assisted-pneumatic oto-endoscopy system.

Pneumatic otoscopes do not support video assisted clinical examination, as they are not equipped with built-in cameras, so diagnosis is based on real-time direct observation rather than on video studying. On the other hand, classic rigid endoscopes usually provide otologists with a clear view of the tympanic membrane and its mobility, allowing subsequent video recording. Unfortunately, rigid endoscopes cannot be used for pneumatic otoscopy, unless they are properly fitted for such use. The aim of this paper is to present a low cost-video assisted-pneumatic oto-endoscopy system based on a conventional rigid endoscope.

Nitric oxide stimulates interleukin-6 production in skeletal myotubes.

Strenuous exercise leads to the up-regulation of interleukin-6 (IL-6) production and enhanced nitric oxide (NO) release within the contracting skeletal muscles. In this study, we investigated whether NO regulates IL-6 production in C2C12 myotubes. These cells exhibited a concentration-dependent increase in IL-6 production upon stimulation with NO donors (Z)-1-[N-(2-aminoethyl)-N-(2-ammonioethyl)amino]diazen-1-ium-1,2-diolate (DETA-NONOate), (Z)-1-[N-(3-aminopropyl)-N-(n-propyl)amino]diazen-1-ium-1,2-diolate (PAPA-NONOate), and sodium nitroprusside (SNP). This treatment did not alter cGMP levels nor did the soluble guanylyl cyclase (sGC) inhibitor, 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one(ODQ), alter this response. The NO-independent sGC activator 5-cyclopropyl-2-[1-(2-fluoro-benzyl)-1H-pyrazolo[3,4-b]pyridin-3-yl]-pyrimidin-4-ylamine (BAY41-2272) and cyclic guanosine monophosphate (cGMP) analog 8Br-cGMP failed to induce IL-6 production. Upon exposure to NO donors, we observed an increase in Erk1/2 and p38 MAPK phosphorylation but not in SAPK/JNK. In addition, NO-induced IL-6 release was inhibited in a concentration-dependent fashion by the MEK1/2 inhibitor PD98059 and the p38 MAPK inhibitor SB203580 but not by the SAPK/JNK inhibitor SP600125. We conclude that NO-stimulated IL-6 production in differentiated C2C12 myotubes is cGMP-independent and mediated by activation of MAPK pathways.

Synthesis and biological evaluation of oxadiazole derivatives as inhibitors of soluble guanylyl cyclase.

Soluble guanylyl cyclase (sGC) is an ubiquitously expressed enzyme that generates the second messenger cGMP and hence, leads to a number of physiological responses including vasodilation, inhibition of platelet aggregation and neurotransmission. Whilst many activating and stimulating modulators of sGC were identified and studied in recent years, only two selective inhibitors are known: ODQ and NS 2028. Furthermore, a synthetic approach to these inhibitors has not been reported yet. Herein, we describe a novel and efficient synthesis of these inhibitors, as well as the preparation of three different classes of NS 2028 analogues. Biological evaluation of this library using rat aortic smooth muscle cells revealed four new compounds with good to moderate sGC inhibitory activity. Our experiments underline the major importance of the oxadiazole ring in ODQ and NS 2028 for the efficiency of this class of inhibitors.

Effects of modulation of the NO/cGMP pathway in tumor cell lines derived from the upper airway tract.

Nitric oxide (NO) is known to be expressed in a variety of cell types and exert its effects through autocrine and paracrine mechanisms. To characterize the NO/cGMP pathway in tumor cells of the upper airway tract, we studied the cell lines Detroit 562, FaDu and FAT7. Using isoform-specific antibodies, we were unable to detect expression of NO synthases in the above-mentioned cells lines. To evaluate whether tumor cells respond to NO, we exposed cells to the NO donor sodium nitroprusside (SNP). Stimulation of Detroit 562 and FaDu with SNP (10 micromol/l to 1 mmol/l) led to a concentration-dependent increase in cGMP accumulation. In addition, incubation of cells with SNP, but not 8 Br-cGMP, reduced Detroit 562 cell number. As exposure of cells to SNP decreased (3)H-thymidine incorporation without inducing DNA fragmentation, we attributed the observed decrease in cell number to inhibition of cell proliferation rather than induction of apoptosis. On the other hand, exposure of Detroit 562 to high concentrations of SNP (1 mmol/l) led to apoptosis and increased the release of vascular endothelial growth factor. We conclude that, although human cell lines derived from the upper airway tract do not produce NO, they respond to NO released by neighboring cells and that exposure to NO exerts an anti-proliferative/apoptotic effect that is independent of cGMP generation.