The Potential Role of Carbon Nanoparticles in Lymph Node Tracing, Recurrent Laryngeal Nerve Identification and Parathyroid Preservation During Thyroid Surgery: A Systematic Review

Background/Objective: Carbon nanoparticles (CNs) are a novel injected suspension used during thyroidectomy in order to black stain the thyroid gland and the lymph nodes while maintaining the anatomic color of the parathyroid glands and the laryngeal nerves. The aim of this systematic review is to investigate the benefits of carbon nanoparticles in thyroid surgical procedures and examine their role in lymph node tracing, parathyroid preservation and recurrent laryngeal nerve protection. Methods: A systematic review of the literature in PubMed/Medline database was performed. Articles reporting randomized clinical trials, prospective and retrospective studies that compared the use of carbon nanoparticles in one group of patients with a control-blank group were included. Results: The search strategy retrieved 22 studies of the literature. Fourteen studies calculated a greater number of lymph nodes detected/dissected in the central neck zone to the patients using CN solution and 1 article noted a higher rate of lymp h nodes resected in the lateral neck zone in the same group of patients. A significant increase in the number of metastatic lymph nodes retrieved in the CN group was found in 7 studies. Twenty -one studies suggested that the use of CNs for protection of the parathyroid glands was beneficial. Transient hypoparathyroidism and transient hypocalcemia were presented with a significant lower incidence in the CN group in 13 and in 8 studies respectively. Conclusion: Carbon nanoparticles may improve both central and lateral neck dissection and enhance parathyroid gland.

Physical-Mechanical Model of Fibrous Polymerized Bar Deformation at the Neck Zone

In the paper the author suggests a model of mechanical deformation of a polymerized bar made of fibres in the neck with regard to forces interacting with a matrix. In the paper, the author suggests an experimental-theoretical method that allows one to define the character of deformation non-homogeneity in the neck area. In particular, analytic dependence of mechanical properties of the material on longitudinal coordinate of the sample is established. Numerical comparison of theoretical results with experimental ones is given.

Numerical study of bluff-body non-premixed flame structures using laminar flamelet model

A laminar flamelet model is applied for bluff-body stabilized flames to study the flow field, mixing pattern, and the flame structure at two different velocities. The k - ɛ turbulence model is applied for accounting the turbulence fluctuations. It is found that the recirculation zone dominates the near field, while the far field structure is similar to the jet flow. The intermediate neck zone is the intense mixing region. The computation shows that the fuel jet velocity has significant effect on the structure of the flow field, which in turn has significant effect on the combustion characteristics. The laminar flamelet model is found to be adequate for simulating the temperature and the flame composition inside the recirculation zone. The flamelet model has, however, failed to account for the local extinction in the neck zone. Possible limitation of the laminar flamelet model to predict the local extinction is discussed.

Immunohistochemical Study of the Expression of MUC6 Mucin and Co-expression of Other Secreted Mucins (MUC5AC and MUC2) in Human Gastric Carcinomas

To investigate the expression of MUC6 mucin in gastric carcinomas, we generated a novel monoclonal antibody (MAb CLH5) using an MUC6 synthetic peptide. MAb CLH5 reacted exclusively with the MUC6 peptide and with native and deglycosylated mucin extracts from gastric tissues. MAb CLH5 immunoreactivity was observed in normal gastric mucosa restricted to pyloric glands of the antrum and mucopeptic cells of the neck zone of the body region. In a series of 104 gastric carcinomas, 31 (29.8%) were immunoreactive for MUC6. The expression of MUC6 was not associated with histomorphological type or with clinicopathological features of the carcinomas. Analysis of the co-expression of MUC6 with other secreted mucins (MUC5AC and MUC2) in 20 gastric carcinomas revealed that different mucin core proteins are co-expressed in 55% of the cases. MUC6 was co-expressed and co-localized with MUC5AC in 45% and with MUC2 in 5% of the cases. Expression of MUC2 alone was observed in 25% of the cases. All carcinomas expressing MUC2 mucin in more than 50% of the cells were of the mucinous type according to the WHO classification. The co-expression of mucins was independent of the histomorphological type and stage of the tumors. In conclusion, we observed, using a novel well-characterized MAb, that MUC6 is a good marker of mucopeptic cell differentiation and is expressed in 30% of gastric carcinomas, independent of the clinicopathological features of the cases. Furthermore, we found that co-expression and co-localization of mucins in gastric carcinomas is independent of histomorphology and staging. Finally, we observed that intestinal mucin MUC2 is expressed as the most prominent mucin of the mucins tested in mucinous-type gastric carcinomas.