Humans are ubiquitously exposed to multiple environmental contaminants. Consequences of combined action on the reproductive system remain unknown. This study aimed to assess single and joint effects of cadmium and diazinon exposure on sperm quality parameters. Male adult Wistar rats were randomized into 4 groups of ten animals each. Group A was used as a control, animals from group B were exposed to cadmium (30 mg/L), rats from group C were administered with diazinon (40 mg/L), and rats from group D were exposed simultaneously to cadmium (30 mg/L) and diazinon (40 mg/L) via drinking water for 90 days. Sperm morphology and motility were evaluated using a bright field microscope and a computer-assisted semen analysis. The percentage of motile spermatozoa and morphologically normal sperm was markedly reduced in rats from the group B. Rats from the C group showed an increase in velocity parameters, amplitude of lateral head displacement, decrease in beat-cross frequency, and an increase in abnormal sperm morphology. Simultaneous coexposure to cadmium and diazinon increased distance and velocity parameters, and amplitude of lateral head displacement. Reductions were observed in straightness, linearity, wobble, and beat-cross frequency. The decreased normal sperm morphology rates were related to defects of the sperm tail. Exposure to cadmium and diazinon at relatively low doses impairs sperm quality and can reduce male fertility. Cadmium and diazinon caused significant changes on sperm morphology with varying effects on motility patterns. These parameters were significantly higher in the group D as compared to the group C. The findings have important implications for reproductive risk assessment of combined exposures to multiple chemicals.

The study investigated the associations of rs9340799:A > G (XbaI) and rs2234693:T > C (PvuII) polymorphisms in the estrogen receptor 1 gene (ESR1) with femoral neck (BMD-FN) and lumbar spine bone mineral density (BMD-LS), biochemical markers of bone turnover, calcium and phosphate levels, fracture prevalence, and a response to two types of anti-osteoporotic therapy in postmenopausal women from southern Slovakia. We analysed 343 postmenopausal Slovak women (62.40 ± 0.46 years). The influence of rs9340799 (AA vs. AG + GG) and rs2234693 (TT vs. TC + CC) genotypes on BMD and biochemical markers was evaluated by covariance analysis adjusted for age and BMI. Binary logistic regression was used to evaluate the genotype effect on fracture prevalence. Pharmacogenetic part of the study included women who received a regular therapy of HT (17ß estradiol with progesterone; 1 mg/day for both; N = 76) or SERMs/raloxifene (60 mg/day; N = 64) during 48 months. The genotype-based BMD change was assessed by variance analysis for repeated measurements. Women with AA genotype of rs9340799 had higher BMD-FN (+ 0.12 ± 0.57 of T-score) and BMD-LS (+ 0.17 ± 0.08 of T-score) in comparison with AG + GG. The rs2234693 polymorphism did not affect any of the monitored parameters. No effect of any ESR1 polymorphisms was found on fracture prevalence. Both types of anti-osteoporotic therapy had a positive effect on BMD improvement in FN and LS sites. Considering the effect of the ESR1 gene within the HT, the subjects with rs9340799/AA genotype showed worse response than those with GG genotype (− 0.26 ± 0.10 of BMD-FN T-score; − 0.35 ± 0.10 of BMD-LS T-score) and also with AG genotype (− 0.22 ± 0.08 of BMD-LS T-score). The rs2234693/TT genotype responded poorer in BMD-LS in comparison with TC (− 0.22 ± 0.08 of T-score) and CC (− 0.35 ± 0.09 of T-score). The effect of the ESR1 gene on raloxifene therapy was reported only in BMD-LS. Subjects with rs9340799/AA genotype had a − 0.30 ± 0.11 of T-score worse response compared to AG genotype. The rs2234693/TT genotype showed − 0.39 ± 0.11 and − 0.46 ± 0.15 lower T-scores in comparison with TC and CC genotypes, respectively. The rs9340799 polymorphism may contribute to decreased BMD in postmenopausal women from southern Slovakia; however, this is not related to higher fracture prevalence. Concurrently, both polymorphisms affected a response to analysed anti-osteoporotic therapies.

Chronic exposure to cadmium (Cd), even at low concentrations, has an adverse impact on the skeletal system. Histologically, primary and secondary osteons as basic structural elements of compact bone can also be affected by several toxicants leading to changes in bone vascularization and mechanical properties of the bone. The current study was designed to investigate the effect of subchronic peroral exposure to Cd on femoral bone structure including histomorphometry of the osteons in adult male rats. In our study, 20 one-month-old male Wistar rats were randomly divided into two experimental groups. In the first group, young males received a drinking water containing 30 mg of CdCl2/L, for 90 days. Ten one-month-old males without Cd intoxication served as a control group. After 90 days of daily peroral exposure, body weight, femoral weight, femoral length, cortical bone thickness and histological structure of the femora were analysed. We found that subchronic peroral application of Cd had no significant effect on body weight, femoral length and cortical bone thickness in adult rats. On the other hand, femoral weight was significantly increased (P < 0.05) in Cd-intoxicated rats. These rats also displayed different microstructure in the middle part of the compact bone where vascular canals expanded into central area of substantia compacta and supplied primary and secondary osteons. Additionally, a few resorption lacunae which are connected with an early stage of osteoporosis were identified in these individuals. Histomorphometrical evaluations showed that all variables (area, perimeter, maximum and minimum diameter) of the primary osteons' vascular canals, Haversian canals and secondary osteons were significantly decreased (P < 0.05) in the Cd group rats. This fact points to alterations in bone vascularization. Subchronic peroral exposure to Cd significantly influences femoral weight and histological structure of compact bone in adult male rats. It induces an early stage of osteoporosis and causes reduced bone vascularization. Histomorphometrical changes of primary and secondary osteons allow for the conclusion that the bone mechanical properties could be weakened in the Cd group rats. The current study significantly expands the knowledge on damaging action of Cd on the bone.

While gross morphological changes in the skeleton between males and females are well know, differences between sexes in the histomorphology are less known. It is important to have knowledge on the bone structure of rabbits, as this is a widely used species in biomedical research. A study was performed to evaluate the association between sex and the compact bone morphology of the femoral diaphysis in juvenile rabbits.

Age estimation based on the counting of incremental lines in dental cementum is a method frequently used for the estimation of the age at death for humans in bioarchaeology, and increasingly, forensic anthropology. Assessment of applicability, precision, and method reproducibility continue to be the focus of research in this area, and are occasionally accompanied by significant controversy. Differences in methodological techniques for data collection (e.g. number of sections, factor of magnification for counting or interpreting “outliers”) are presented. Potential influences on method reliability are discussed, especially for their applicability in forensic contexts.