Treatment of Benign C2 Tumors with Transoral Curettage and Posterior Instrumentation with Minimum 2-Year Follow-Up: Technical Note.

Background: Tumors of the axis (C2) are rare, which represents unique surgical challenges. Aim: To describe clinical outcomes and efficacy of transoral curettage and posterior instrumentation for treating C2 tumors, with a minimum 2-year follow-up. Setting and Design: This was a retrospective study conducted at a grade 3A hospital in China. Materials and Methods: From August 2015 to May 2017, patients diagnosed with benign C2 tumors were collected in the retrospective study. The Weinstein-Boriani-Biagini anatomic zone classification was used to characterize the tumors. The Japanese Orthopedic Association (JOA) score and the visual analog scale (VAS) pain scores were recorded pre and postoperatively. All patients were treated with posterior instrumentation and transoral curettage for tumor excision and iliac crest graft for arthrodesis. Results: Five patients were included in this report. The tumors involving C2 were all benign tumors. The JOA and VAS scores improved significantly at a 3-month follow-up, and the clinical symptoms were stable at the 12-month follow-up. Computed tomography (CT) scans at a 6-month follow-up showed solid arthrodesis in all patients. With a minimum 2-year follow-up, there was no implant loosening or tumor recurrence. Conclusion: The transoral curettage coupled with posterior instrumentation with iliac crest graft provides a reasonable option for the treatment of benign C2 tumors.

Differentiation of Pigment in Eggs Using Carbon ((13)C/(12)C) and Nitrogen ((15)N/(14)N) Stable Isotopes.

Consumers prefer natural and healthy food, but artificial pigments are often abused in egg products. The study aimed at differentiating the origin of pigments in eggs by applying the technique of carbon ((13)C/(12)C) and nitrogen ((15)N/(14)N) stable isotope analysis. Five hundred sixty laying hens were randomly distributed into 14 treatments, which were divided into four groups: maize, carophyll red pigment, carophyll yellow pigment, and a mixture of carophyll red and yellow pigments. Eggs were collected and pretreated to determe the values of the Roche Yolk Color Fan (RCF), δ(13)C, and δ(15)N. With increasing maize content, the RCF and δ(13)C values of yolks increased. Moreover, the RCF values in the three pigment groups were significantly influenced by the artificial colors, but δ(13)C values were not significantly different, regardless of the existence of pigment. The δ(15)N values in all treatments did not vary as regularly as the carbon stable isotope. A strong positive correlation was found between RCF and δ(13)C in the maize group, but no such correlation was be observed in the pigment groups. It is concluded that carbon stable isotope ratio analysis (δ(13)C) of the yolk can be used to differentiate the origin of the pigment added to eggs.