Comparative Study of Optical Markers to Assess Bait System Efficiency Concerning Vaccine Release in the Oral Cavity of Dogs

Oral vaccination of dogs against rabies has the potential to achieve mass coverage and thus deplete the virus of its most important reservoir host species. There is, however, no established non-invasive method to evaluate vaccine release in the oral cavity, following bait ingestion. In this study, two pre-selected marker methods in conjunction with their acceptance were assessed in local Thai dogs. Shelter dogs (n = 47) were offered one of four randomized bait formulations; bait type A-, containing Green S (E142) in a fructose solution; type B-, containing Patent Blue V (E131) in a fructose solution; type C-, containing the medium used for delivery of oral rabies vaccine in baits commercially produced; and type D-, containing denatonium benzoate, which was to serve as the negative control, due to its perceived bitterness. Patent Blue V was found to possess overall stronger dyeing capacities compared to Green S. Furthermore, there was no significant difference in the acceptance or bait handling of Patent Blue V baits compared to those containing the oral rabies vaccine medium alone, suggesting the potential use of this dye as a surrogate for rabies vaccine when testing newly developed bait formats.

Exploratory Study of the Clinical Value of Near-Infrared Sentinel Lymph Node Mapping With Indocyanine Green in Vulvar Cancer Patients

BackgroundThis study aimed to evaluate the clinical value of indocyanine green sentinel lymph node (SLN) mapping in patients with vulvar cancer. The conventional procedure of SLN mapping in vulvar cancer includes peritumoral injection of technetium-99m nanocolloid before surgery and intraoperative injection of a blue dye. However, these techniques harbor some limitations. Near-infrared fluorescence imaging with indocyanine green has gained popularity in SLN mapping in different types of cancer.MethodsWe analyzed retrospectively vulvar cancer patients at our institution between 2013 and 2020 undergoing indocyanine green SLN mapping by applying video telescope operating microscope system technology.Results64 groins of 34 patients were analyzed. In 53 groins we used technetium-99m nanocolloid, in four patent blue, and in five both techniques, additionally to indocyanine green for SLN detection. In total, 120 SLNs were identified and removed. The SLN detection rate of indocyanine green was comparable to technetium-99m nanocolloid (p=.143) and higher than patent blue (p=.003). The best results were achieved using a combination of ICG and technetium-99m nanocolloid (detection rate of 96.9%). SLN detection rates of indocyanine green were significantly higher in patients with positive lymph nodes (p=.035) and lymphatic space invasion (p=.004) compared to technetium-99m nanocolloid.ConclusionIndocyanine green SLN mapping in vulvar cancer is feasible and safe, with reasonable detection rates. Due to its easy application and few side effects, it offers a sound alternative to the conventional SLN mapping techniques in vulvar cancer. In patients with lymph node metastasis, indocyanine green even outperformed technetium-99m nanocolloid in terms of detection rate.

Natural Blues: Structure Meets Function in Anthocyanins

Choices of blue food colourants are extremely limited, with only two options in the USA, synthetic blue no. 1 and no. 2, and a third available in Europe, patent blue V. The food industry is investing heavily in finding naturally derived replacements, with limited success to date. Here, we review the complex and multifold mechanisms whereby blue pigmentation by anthocyanins is achieved in nature. Our aim is to explain how structure determines the functionality of anthocyanin pigments, particularly their colour and their stability. Where possible, we describe the impact of progressive decorations on colour and stability, drawn from extensive but diverse physico-chemical studies. We also consider briefly how this understanding could be harnessed to develop blue food colourants on the basis of the understanding of how anthocyanins create blues in nature.

O69: THE SENTINEL LYMPH NODE TECHNIQUE IN THE ENDOMETRIAL CANCER

Introduction The sentinel lymph node (SLN) concept represents advancement in the management of the endometrial cancer (EC). We aim to assess the performance of the SLN procedure; its positive predictive value (PPV) and negative predictive value (NPV); in stage I of EC (FIGO2009). Method A prospective study is conducted in our institution. We perform a double detection of the SLN (radiolabel Tc 99 microsulfur colloid and a color method using patent blue) followed by pelvic lymphadenectomy with or without paraaortic lymphadenectomy. A pelvic MRI is performed to determine myometrial invasion and nodal status. The injection of Tc 99m colloid occurs the day prior to surgery. The injection into the stroma of the cervix at the 3 and 9 o'clock positions was performed by an oncologist surgeon with the assistance of a nuclear medicine physician. Preoperative lymphoscintigraphy was obtained after 90-120 minutes. We inject into the cervical stroma 2cc of patent blue similar to the Tc99 injection. A gamma detecting probe is used to locate radioactive lymph nodes. The SLNs identified then are labelled as radioactive and/or blue. No frozen-section analysis was performed. Results For the pathological analysis of the SLN, Haematoxylin Eosin is used. If there is no metastasis detected, an ultra staging protocol using different anti-cytokeratines is conducted. Studies have shown that this approach is possible having satisfactory results when conducted by dedicated surgical, radiology and pathology team. We look forward to our outcomes to illustrate those results. Take-home message Sentinel lymph node is a good alternative for gynecological cancer