Critical evaluation of the use of total reflection X-ray fluorescence spectrometry for the analysis of whole blood samples: application to patients with thyroid gland diseases.

Multielemental analysis of whole blood can provide significant information for the evaluation of nutritional status and diagnosis of certain diseases as well as for the assessment of exposure to potentially toxic metals. However, the quantification of multiple elements in whole blood is not easy partly because of the wide variation in element concentrations (from ng L-1 to g L-1) and the complex matrix. The aim of this work was to develop a fast, sustainable, and reliable analytical method, in combination with low-power TXRF, for multielemental analysis of blood samples. Firstly, a set of experiments were carried out to select the best diluent type and dilution factor using the control material SeronormTM Trace Elements Whole Blood L-1. A critical evaluation of the parameters affecting the sample deposition on the reflector was also carried out including a study of the shape and element distribution of the deposited residue on the reflector by micro X-ray fluorescence spectrometry. Using the best analytical conditions, limits of detection estimated were in the low milligrams per kilogram range and similar to those obtained using more complex sample treatments such as digestion. Accuracy and precision of the results were in most cases acceptable (recoveries 89-102%, RSD 6-8%, n = 5). Only underestimated values were obtained for light elements such as potassium. To prove the applicability of the method, several blood samples from control and thyroid disease patients were analyzed. Despite the fact that more samples need to be analyzed, it seems that Zn and Br contents in some of the patients are significantly higher compared to control samples. Graphical abstract.

Cytogenetic status and oxidative stress parameters in patients with thyroid diseases.

Since the incidence of cancer has increased over the years, adequate prevention programmes are needed. Thyroid cancer is one of the fastest growing cancer types in the world. In this study we performed a case-control study of 100 untreated patients with thyroid diseases (papillary thyroid cancer, follicular thyroid adenoma, and other thyroid diseases) and 100 control volunteers. Oxidative status differed among the two investigated groups. The patients' group had 1.60-fold higher concentrations of malondialdehyde and 1.26-fold higher concentrations of protein carbonyls. At the same time, the concentrations of glutathione and catalase activity were by 32% and 35% lower, respectively. A similar effect was observed for the cytogenetic status where higher comet assay tail intensity (1.84-fold) and the total numbers of chromosome aberrations (1.47-fold), micronuclei (2.32-fold), nucleoplasmic bridges (3.98-fold), and nuclear buds (2.34-fold) were detected. As for protein expression in thyroid tissue, 97.89% were positive for either B-Raf or Ret. Interestingly, the papillary thyroid cancer patients more frequently expressed B-Raf proteins compared to the follicular thyroid adenoma patients and patients with other thyroid diseases. Human biomonitoring studies enable a risk assessment of general population, such data could be used to identify risk subgroups.

A case-control study of genotoxicity endpoints in patients with papillary thyroid cancer.

Thyroid cancer is one of the fastest growing cancer types worldwide. Using the cytokinesis-block micronucleus (CBMN) and comet assays, we performed a case-control study of 23 untreated papillary thyroid cancer (PTC) patients and 23 healthy volunteers. PTC patients showed higher basal DNA damage in peripheral blood lymphocytes. The CBMN assay indicated that the numbers of micronuclei, nuclear buds, and nucleoplasmic bridges among the cases were 2.67-, 2.79-, and 7.72-fold higher, respectively, than among the controls (p < 0.05). Comet assay tail lengths and tail intensities were 1.20- and 1.94-fold higher, respectively (p < 0.05). In additional, 14 thyroid tissues from PTC patients were probed for Raf-B and Ret expression; all samples were positive for at least one of these proteins.

The value of frozen section in intraoperative surgical management of thyroid follicular carcinoma.

BACKGROUND: Preoperative and intraoperative diagnosis of follicular carcinoma (FC), resulting in one-stage surgical treatment of follicular thyroid tumors, is an important issue in thyroid surgery. METHODS: In the 10-year period there were 4158 operations performed on thyroid gland. There were 1559 patients with follicular tumors, 70 (4.4%) of them having FC. We analyzed the groups of patients with FC determined on frozen section (FS) and permanent section (PS) according to duration of clinical symptoms, ultrasound (US) examination, tumor size, patient gender and age, intensity of invasion, localization, and multiple or solitary occurrence of tumor. RESULTS: FC was diagnosed in 39 (55.7%) patients on frozen section (FS). Among the encapsulated (minimal invasion) carcinomas, the FS was accurate in 19 of 33 (57.6%) FC and in 5 of 15 (27.8%) Hürthle cell carcinomas (HCC); among extensively invasive carcinoma in 11 of 14 (78.6%) FC and in 4 of 5 (80.0%) HCC. FC was significantly more common in men (p <.001) and in the right lobe (p <.05). We did not find statistically significant differences concerning duration of symptoms, US examination, tumor size, patient age, and multiple or solitary occurrence of the tumor between the patients with FC diagnosed on FS and the patients with FC diagnosed on PS. CONCLUSIONS: The intraoperative diagnosis of FC is difficult. Although the percentage of false-negative results was relatively high (44.3%), there were no false-positive results. This means that the second operation was avoided in 55.7% of the patients, and no unnecessary thyroidectomies were performed. FS biopsy is an important method in surgery of follicular tumors. Improved technical support and the ability to analyze a greater number of slides will increase the accuracy of the method.