Betonica bulgarica is an endemic species distributed in Bulgaria. The chemical composition of the essential oil analysed by GC–MS (Gas chromatography–mass spectrometry) and the content of trace elements analysed by ICP–MS (Inductively coupled plasma mass spectrometry) were determined. Additionally, a study on the types and distribution of trichomes was done using a microscope with a camera. The essential oil was characterized using a high concentration of sesquiterpene hydrocarbons, whose major compounds are β-caryophyllene (17.4%), germacrene D (9.9%), and β-bourbonene (6.7%). The contents of manganese (177.2 µg/g) and strontium (156.8 µg/g) were highest among the investigated micronutrients. Two types of trichomes were identified on the adaxial and abaxial epidermises of the leaves of B. bulgarica—covering and glandular. Peltate stacked glandular trichomes with a four-celled head of type B were observed on the leaf surface.

Introduction: Metal ions, released from dental alloys due to corrosion, come in contact with the cells of the surrounding tissues and may spread throughout the body via the gastrointestinal system, thus inducing dose-dependent cytopathological effects. This study aimed to assess and compare the salivary cobalt and chromium concentrations in individuals aged 18–65 years with and without dental restorations containing metal alloys. Methods: Participants were divided into two main groups according to the existence of metal alloys in the oral cavity—18 patients had fixed prosthetic restorations made of metal alloys, and 17 patients had no metal objects in their oral cavity. Each main group was subdivided into two subgroups according to the type of saliva sample—with or without additional stimulation. Salivary cobalt and chromium concentrations were measured by inductively coupled plasma mass spectrometry. A non-parametric Mann–Whitney test and Spearman’s rank correlation coefficient were applied, and the level of significance was set to p < 0.05. Results: The results showed that the chromium level in non-stimulated saliva was higher in the group of patients with metal dental restorations. No statistical difference was found in cobalt levels. There was no statistical difference in Co or Cr concentrations in stimulated saliva between the studied groups. A positive correlation was found between Cr and Co concentrations in non-stimulated saliva and between cobalt concentrations in stimulated and non-stimulated saliva. Conclusions: Metal alloys in the oral cavity induced elevated chromium levels in non-stimulated saliva, and a correlation between chromium and cobalt ion concentration was found. A detailed examination of patients and their medical history prior to prosthetic treatment is advisable in order to avoid any undesired health effects.

Background. CAD/CAM technologies facilitate using powder CoCr alloys to produce metal-ceramic dental restorations. However, base alloys may induce oxidative stress in the oral cavity due to corrosion and ion release. This study evaluated resistance to corrosion and release of metal ions from 3D printed CoCr dental alloy and their effect on oral oxidative stress. Methods. Metal-ceramic crowns with 3D printed copings from CoCr alloy EOS CobaltChrome SP2 (EOS, Germany) were fabricated for 35 patients. Inductively coupled plasma mass spectrometry (ICP-MS) was used for measuring the concentration of Co and Cr ions in non-stimulated saliva before prosthetic treatment (BPT), at 2 h and 7 days after the dental treatment (APT2, APT7, respectively). Open circuit potentials (Eocp) were evaluated at APT2 and APT7. Estimating oral oxidative stress, measurements of 8-isoprostaglandin F2-alpha were conducted using liquid chromatography-tandem mass spectrometry (LC-MS/MS) at stages BPT, APT2, and APT7. Results. Salivary Co level increased at APT2 and decreased to the initial levels at APT7. No statistical difference was found between the levels of 8-isoPGF2-alpha measured, and between the Eocp measurements at APT2 and APT7. Conclusions. The studied alloy showed stable corrosion resistance and the metal ion release did not induce oral oxidative stress.

Thyroid dysfunction is frequently associated with disturbances of calcium and phosphorus homeostasis. Previous studies on bone and mineral metabolism in women with autoimmune thyroiditis (AIT) and hypothyroidism have conflicting results. The aim of the present work was to study the parameters of calcium-phosphorus metabolism in women with newly diagnosed autoimmune hypothyroidism and to compare them with those of the control group of healthy women. The study included 64 women with newly diagnosed autoimmune hypothyroidism. A comparison was made with the data of 75 age-, BMI- and menopausal state-matched healthy women. FT3, FT4, TSH, TPO-Ab, TG-Ab, total and ionized serum calcium, inorganic phosphate, magnesium, parathyroid hormone (PTH) and 25(OH) vitamin D were studied. Total and ionized calcium were lower in hypothyroid women in the absence of statistically significant difference compared to the controls. Intergroup analysis revealed no differences in serum phosphorus and 25(OH)D levels. Serum magnesium and PTH were significantly higher in hypothyroid group. These results coincide with some of the studies that examine the parameters of bone and mineral metabolism in hypothyroidism. Bone turnover is suppressed due to impaired mobilization of calcium from the bone, leading to decreased serum calcium levels and elevated PTH. We found a significant effect of thyroid hormones on magnesium homeostasis. The study did not find differences in vitamin D status between the groups. The observed inverse correlation between 25(OH)D and TgAb supports the concept of pathogenic relationship between vitamin D and the development of AIT.

Background: Environmental and physiological factors influence human ionom, which requires the development of reliable region-specific reference intervals (RIs). This study aimed to establish population-based RIs of copper (Cu), zinc (Zn), selenium (Se), rubidium (Rb), and magnesium (Mg), in relation to age, sex, and physical activity. Methods: The RIs were established according to the CLSI EP28-A3c guidelines. A reference group of 120 directly selected healthy volunteers of Bulgarian nationality (60 males and 60 females, aged 18 to 65 years) were included in the study. The participants were separated into two groups: low (2 h/week, n=60) physical activity. Serum levels of Cu, Zn, Se, Rb, and Mg (sCu, sZn, sSe, sRb, sMg), were determined via collision cell inductively coupled plasma mass spectrometry (ICP-MS). Results: The RIs in this study are generally comparable to those in other countries. However, 43% of the participants had sSe lower than the threshold of 80 µg/L, correlating with the optimal expression of key selenoproteins. A significant sex-related difference was found for Cu (male vs female, p = 0.003), as well as an age-related significant difference for Cu between the groups of women below and above 30 years of age (p = 0.001). Conclusions: In this study, we verified the RIs of sCu, sZn, sSe, and sMg for the Bulgarian population with ICP-MS. A RI of sRb, missing up to the present was established, thus filling the gap. Specific sex-, age-, and physical activity-related associations of the elements were elucidated.