Occult Contralateral Lateral Lymph Node Metastases in Unilateral N1b Papillary Thyroid Carcinoma

World Journal of Surgery - Therapeutic lateral neck dissection (ND) is recommended for N1b papillary thyroid carcinoma (PTC), while prophylactic contralateral lateral ND is not. Given the paucity...     

Intraoperative Near-infrared Imaging for Parathyroid Gland Identification by Auto-fluorescence: A Feasibility Study

Background

Parathyroid glands (PGs) can be particularly hard to distinguish from surrounding tissue and thus can be damaged or removed during thyroidectomy. Postoperative hypoparathyroidism is the most common complication after thyroidectomy. Very recently, it has been found that the parathyroid tissue shows near-infrared (NIR) auto-fluorescence which could be used for intraoperative detection, without any use of contrast agents. The work described here presents a histological validation ex vivo of the NIR imaging procedure and evaluates intraoperative PG detection by NIR auto-fluorescence using for the first time to our knowledge a commercially available clinical NIR imaging device.

Methods

Ex vivo study on resected operative specimens combined with a prospective in vivo study of consecutive patients who underwent total or partial thyroid, or parathyroid surgery at a comprehensive cancer center. During surgery, any tissue suspected to be a potential PG by the surgeon was imaged with the Fluobeam 800 ^® system. NIR imaging was compared to conventional histology (ex vivo) and/or visual identification by the surgeon (in vivo).

Results

We have validated NIR auto-fluorescence with an ex vivo study including 28 specimens. Sensitivity and specificity were 94.1 and 80 %, respectively. Intraoperative NIR imaging was performed in 35 patients and 81 parathyroids were identified. In 80/81 cases, the fluorescence signal was subjectively obvious on real-time visualization. We determined that PG fluorescence is 2.93 ± 1.59 times greater than thyroid fluorescence in vivo.

Conclusions

Real-time NIR imaging based on parathyroid auto-fluorescence is fast, safe, and non-invasive and shows very encouraging results, for intraoperative parathyroid identification.

     

Supernumerary outer hair cells arise external to the last row of sensory cells in the organ of corti

During the development of the mammalian inner ear, the number of hair cells produced is highly regulated and remains constant throughout life. The mechanism underlying this regulation is beginning to be understood although many aspects still remain obscure. When late embryonic or early postnatal rat organs of Corti were cultured, the production of supernumerary hair cells was observed. This overproduction of sensory cells could be modulated by the addition of several growth factors. In this study, we examined explants of rat organs of Corti that produced supernumerary hair cells. In the supernumerary hair cell region, up to two rows of inner hair cells and five rows of outer hair cells were observed. Morphological evaluation of these specimens revealed that less mature hair cells were located in the most external rows of these sensory cells. When a supernumerary hair cell was produced, a supporting cell (i.e. Deiters' cell) was also produced, strongly suggesting that the conversion of a Deiters' cell into a hair cell was not the mechanism that produced these extra hair cells. Based on these results, we propose that prosensory cells located at the external edge of the organ of Corti retain a capacity to form hair cells and that it is these prosensory cells that differentiate into supernumerary hair cells and Deiters' cells.     

Striatal PSA-NCAM(+) precursor cells from the newborn rat express functional glycine receptors

Immunocytochemical analysis showed that ionotropic glycine receptors are expressed in neurogenic progenitors purified from the newborn rat striatum and expressing the polysialylated form of the neural cell adhesion molecule, both in vitro and in situ. To ascertain whether glycine receptors were functional in vitro, whole-cell patch-clamp recordings demonstrated that glycine triggers inward strychnine-sensitive currents in the majority of these cells. Moreover, we found that glycine receptors expressed by these neurogenic progenitors display intermediate electrophysiological characteristics between those of glycine receptors expressed by neural stem cells and by mature interneurons from the rat striatum. Altogether, the present data show that functional strychnine-sensitive glycine receptors are expressed in neurogenic progenitors purified from the newborn rat striatum.     

Recurrent immuno-allergic hepatitis related to amoxicillin-clavulanic acid

We report on a patient who presented, on 2 occasions at one-year interval after a treatment with the amoxicillin-clavulanic acid association, a clinical and biological picture in keeping with the diagnosis of immuno-allergic hepatocellular hepatitis. On liver biopsies, the most characteristic finding was portal and lobular eosinophilic infiltration without cholestasis and biliary ducts damage.