Matúš Kúdela

Salivary thiobarbituric acid reacting substances and malondialdehyde - Their relationship to reported smoking and to parodontal status described by the papillary bleeding index

Background. Thiobarbituric reacting substances (TBARS) are markers of lipoperoxidation. The best-known specific TBARS is malondialdehyde (MDA). Results from our previous studies have shown that TBARS can be measured in saliva and are increased in patients with gingivitis. Whether MDA is the main TBARS in saliva from patients with altered parodontal status is unknown. Aim. To observe the relationship between the parodontal status and TBARS, MDA and the number of epithelial cells in saliva. Subjects & Methods. In Study I saliva and plasma samples of 15 patients (8F, 7M) suffering from inflammatory periodontal diseases were gathered and TBARS levels were measured in these samples. In Study II saliva samples from 217 consecutive stomatologic patients were collected and analysed for TBARS spectrofluorometrically, MDA by high-performance liquid chromatography and epithelial cell count by light microscopy. Papillary bleeding index (PBI) was determined in standard stomatologic examination. Results. In Study I results from our previous studies showing no correlation between salivary and plasma TBARS levels were confirmed. This indicates that the local salivary level of TBARS is unlikely to be directly affected by systemic oxidative stress. In Study II higher PBI was associated independently (adjusted for age and sex) tightly with higher TBARS (p < 0.001) and with lower number of epithelial cells in saliva (p < 0.05). Smokers had higher salivary MDA levels (p < 0.003) and lower number of epithelial cells in saliva (p < 0.01). Conclusion. Salivary TBARS are a simple parameter that partially reflects the parodontal status with a potential usefulness in the clinical stomatology. We show herein that salivary MDA is dependent on age and smoking, but there is no correlation between MDA and PBI. Further studies should uncover the main salivary TBARS compound in patients with altered parodontal status and trace the origin of these salivary lipoperoxidation markers.

Endocrine and cognitive effects of short-time soybean consumption in women.

Background: Soy phytoestrogens are known to influence the hormonal status acting as partial estrogen agonists. Soy-derived food supplements are advised for hormone replacement therapy, prevention of atherosclerosis, age-related cognitive decline and even hormone-dependent cancer, although results from clinical studies are controversial. Whether increased soybean intake can affect the endocrine status and cognitive abilities is largely unknown. Aim: To observe the effects of 1 week of increased soybean intake on sex hormone levels and spatial cognitive abilities in women. Subjects and Methods: 16 young healthy female volunteers were asked to eat 900 g of soybeans within 1 week. Salivary testosterone (T), free and total plasma T, salivary and plasma estradiol (E) were measured by radioimmunoassay before and after the study period. Mental rotation (MR) and spatial visualization (SV) psychological tests were done at the days of sampling. Results: Soybean intake increased total plasma T levels (p < 0.02) while decreasing salivary T (p < 0.01) and not altering free plasma T levels. Salivary and plasma E levels were not changed. The results of MR and SV tests were improved after the study period. Conclusion: Short-time increased soybean intake alters the level of total plasma and salivary T and improves spatial cognition in women. Whether this effect is mediated by modulation of estrogen receptors, changes in sex hormone-binding globulin production or changes in activity of steroid-competent enzymes needs further study.

Intelligence and salivary testosterone levels in prepubertal children.

BACKGROUND Hormones are one of the regulatory systems influencing brain-cognition interactions and subsequent emotions and behavior in humans and animals. Sex hormones have been found to influence brain structures prenatally, so as to prepare targeted neuronal circuits for activation during and after puberty. Testosterone is believed to affect cognition and thinking in humans as well as between-sex differences in cognitive abilities. AIM The aim of this paper was to investigate associations between testosterone and different levels of intelligence in young prepubertal children of both sexes. METHODS Two hundred and eighty four prepubertal children of both sexes between 6 and 9 years of age provided saliva samples. Of these, 107 were intellectually gifted (IQ above 130), 100 children of average intelligence--randomly chosen from general population (IQ between 70 and 130), and 77 children mentally challenged (IQ less than 70). RESULTS Our results have revealed the differences in salivary testosterone levels in boys grouped according to IQ, intellectually gifted and mentally challenged boys having lower salivary testosterone levels than their peers characterized by average intelligence proposing the common biological characteristic of minority IQ groups on both ends of the Gauss curve. In girls, no differences in salivary testosterone levels were found among IQ groups. CONCLUSIONS Our findings are the first that present the relationship between testosterone and the broad range of general IQ in childhood. The boys of average intelligence had significantly higher testosterone levels than both mentally challenged and intellectually gifted boys, with the latter two groups showing no significant difference between each other. The functional implications of the brain-cognition interactions remain to be fully explored with regard to the internal milieu influencing neural substrate.

Outbreaks of blackflies and related problems in Serbia: past and present situation

Due to the repeated outbreaks of blackflies, consequent economical losses and health problems, Serbia was considered as the most threatened European country in the past. During the last century (up to `60s), Simulium colombaschense caused enormous losses of livestock. Significant losses in poultry production caused by S. maculatum were also reported in 1958, while S. erythrocephalum caused severe dermatological problems in humans in 1965 and 1970. In the last fifteen years, repeated outbreaks of blackflies and reemerging of bite related problems in humans were recorded in some parts of Serbia. The research objective was to update the knowledge of blackfly pest species distribution in Serbia, with a special attention to endangered regions in the present and the past. Samplings were conducted in the period 2003-2012. Immature stages were collected from submerged substrates: in the Danube river and its tributaries, the Nera river and the Nisava river. Adults were sampled close to the breeding sites by application of CO2 baited traps or by light traps. In the lowlands 11 blackfly species were recorded. Two mammophilic species have been dominant: S. erythrocephalum in the Danube and S. ornatum (complex) in confluent streams. In 2010, S. erythrocephalum was recorded for the first time in the hilly area in southeastern Serbia. Periods of high adult population density of those two species coincided with the bite cases reports. In the Iron Gate region, 21 mainly mammophilic species were recorded in the Danube confluents exclusively. S. colombaschense, the main pest species in the past, was detected only in the Nera river, about 30 km upstream from the entrance of the Iron Gate. Present state of blackfly fauna composition indicates the existing risk of outbreaks of some species in the future. Acknowledgements: The study was supported by The Ministry of Education, Science and Technological Development of the Republic of Serbia (projects TR31084 and III43007).

Salivary markers of oxidative stress are related to age and oral health in adult non‐smokers

BACKGROUND Salivary concentrations of thiobarbituric acid-reacting substances (TBARS) are associated with the periodontal status assessed as papillary bleeding index (PBI). Whether this association is age independent is currently unclear. Salivary concentrations of advanced oxidation protein products (AOPPs) and advanced glycation end products (AGEs) have not been assessed in relation to age or oral health yet. The aim of our study was to analyse salivary markers of oxidative stress in dental patients in relation to age, gender and oral health. METHODS Consecutive adult non-smoking dental patients were enrolled (n = 204; aged 19-83 years). PBI and the caries index (CI) were assessed. Markers of oxidative stress, such as TBARS, AOPPs and AGEs, and the total antioxidant capacity (TAC) were measured in saliva samples taken before clinical examination. RESULTS Linear regression showed that salivary TBARS, AGEs and TAC significantly increase with age (r squared = 5.3%, 2.1% and 5%, respectively). PBI is an independent predictor of salivary TBARS (r squared = 5.5%), and the CI negatively affected AOPPs (r = 3.2%) and positively affected TBARS (r = 2.5%). Gender did not affect any of the analysed parameters. CONCLUSIONS Age as a significant contributor to the variance should be taken into account in studies focusing on salivary markers of oxidative stress. The relationship between PBI and salivary TBARS confirms results from previous studies. In addition, our results show that the association is age independent. Negative association between the CI and AOPPs might be related to recent findings that AOPP might be actually a marker of non-enzymatic antioxidant status.

Circatrigintan cycle of salivary testosterone in human male

Background. Circadian and circannual cycles of testosterone (T) in men are known. The results of our previous study have shown indices for the existence of a male circalunar cycle of T similar to the female one. Objective. The purpose of this study was to investigate possible infradian rhythms of salivary T in young healthy men. Subjects & Methods. Saliva samples from 31 healthy men (18–25 years of age) were collected every second day (for 1 month) and every third day (during the following 1.5 months). T levels were determined by radioimmunoassay. Data were statistically analyzed for infradian rhythmic changes using two different methods: moving averages – zones of extremes, and analysis of rhythmic variance. Results. The data showed rhythmic variations with 2 different infradian periods. The differences between extreme values of the circatrigintan (period of 30 days) and circavigintan (period of 20 days) cycles were found to be highly significant (p < 1E-9; p < 1E-8). Conclusion. We believe that this is the first study demonstrating the existence of circatrigintan and circavigintan rhythms of testosterone in human males. Our findings might have implications in human physiology and pathophysiology.

Use of inter-simple sequence repeat (ISSR) markers for discrimination between and within species of blackflies (Diptera: Simuliidae)

The present study is the first report of fingerprinting in blackflies (Diptera: Simuliidae), using inter-simple sequence repeat (ISSR) markers. Among five primers tested, three tetranucleotide repeat primers ((GACA)4, (ACTG)4, (ACAG)4) generated a high proportion of polymorphic bands. Seven species representing various genera, subgenera or species groups were compared. No similar profiles were found. Intraspecific and interspecific banding patterns were analysed for two species in the Prosimulium hirtipes (Fries, 1824) species group and four species in the Simulium variegatum (Meigen, 1818) species group. The UPGMA cluster analysis based on Jaccard’s coefficient demonstrated the intraspecific and interspecific diversity and the resolving power of the ISSR markers to differentiate blackfly species and populations. In Simulium maximum (Knoz, 1961), geographically defined populations were successfully discriminated.

Cryptic Biodiversity and the Origins of Pest Status Revealed in the Macrogenome of Simulium colombaschense (Diptera: Simuliidae), History’s Most Destructive Black Fly

The European black fly Simulium (Simulium) colombaschense (Scopoli), once responsible for as many as 22,000 livestock deaths per year, is chromosomally mapped, permitting its evolutionary relationships and pest drivers to be inferred. The species is 12 fixed inversions removed from the standard sequence of the subgenus Simulium. Three of these fixed inversions, 38 autosomal polymorphisms, and a complex set of 12 X and 6 Y chromosomes in 29 zygotic combinations uniquely characterize S. colombaschense and reveal 5 cytoforms: ‘A’ in the Danube watershed, ‘B’ in Italy’s Adige River, ‘C’ in the Aliakmonas River of Greece, ‘D’ in the Aoös drainage in Greece, and ‘E’ in the Belá River of Slovakia. ‘C’ and ‘D’ are reproductively isolated from one another, and ‘B’ is considered a cytotype of ‘A,’ the probable name bearer of colombaschense. The species status of ‘E’ cannot be determined without additional collections. Three derived polytene sequences, based on outgroup comparisons, place S. colombaschense in a clade of species composed of the S. jenningsi, S. malyschevi, and S. reptans species groups. Only cytoforms ‘A’ and ‘B’ are pests. Within the Simuliidae, pest status is reached through one of two principal pathways, both of which promote the production of large populations of blood-seeking flies: (1) colonization of the world’s largest rivers (habitat specialization) or (2) colonization of multiple habitat types (habitat generalization). Evolutionary acquisition of the ability to colonize large rivers by an ancestor of the S. jenningsi-malyschevi-reptans clade set the scene for the pest status of S. colombaschense and other big-river members of the clade. In an ironic twist, the macrogenome of S. colombaschense reveals that the name associated with history’s worst simuliid pest represents a complex of species, two or more of which are nonpests potentially vulnerable to loss of their limited habitat.

Increased one week soybean consumption affects spatial abilities but not sex hormone status in men

Background Increased soybean intake is often recommended for the prevention of hormone-dependent cancer, cardiovascular diseases and age-related cognitive decline. Although isolated phytoestrogens have shown these positive effects, the evidence for such influence of increased consumption of soybeans is lacking. Aim To prove the effects of short-term increased soybean intake on sex hormone levels and spatial cognitive parameters in men. Subjects and methods Seven young healthy men were asked to eat 900 g soybeans during 1 week. Sex hormone levels were determined in saliva and plasma, and mental rotation and spatial visualization were quantified by standard psychometric tests. All parameters were assessed before and after the study. Results Plasma estradiol, total and free testosterone, as well as salivary testosterone and estradiol remained unchained. Spatial cognitive performance was improved after increased soybean intake when considering spatial visualization (P=0.03). The results for mental rotation showed similar dynamics, but the changes were not significant. Conclusion Short-term increased soybean intake does not affect sex hormone status, but improves spatial cognitive performance in young healthy men.

Spatial Abilities in Prepubertal Intellectually Gifted Boys and Genetic Polymorphisms Related to Testosterone Metabolism

Spatial abilities are known to be related to testosterone levels in men. Polymorphisms of genes related to androgen metabolism, however, have not been previously analyzed in association with spatial abilities. Our study analyzes genetic polymorphisms of androgen receptor (AR), aromatase (CYP19), and 5-alpha reductase (SRD5A2) in relation to mental rotation and spatial visualization in prepubertal intellectually gifted boys. DNA samples of 36 boys with an average age of 10.0 ± 0.7 years and an IQ higher than 130 were isolated from buccal cells in saliva. DNA was subsequently used for amplification by PCR. The CYP19 C1558-T polymorphism and SRD5A2 A49T polymorphism were determined by RFLP analysis, and the AR (CAG)n polymorphism was determined by fragment analysis. Salivary testosterone levels were measured with radioimmunoassay. Spatial abilities (mental rotation and spatial visualization) were assessed using standard psychometric tests. AR and CYP19 polymorphisms were not associated with spatial abilities...