Assessment of cytogenetic damage in lymphocytes and in exfoliated nasal cells of dental laboratory technicians exposed to chromium, cobalt, and nickel

Dental laboratory technicians may be exposed to metal alloys that are used in the production of crowns, bridges and removable partial dentures. These alloys consist of 35–65% cobalt, 20–30% chromium, 0–30% nickel, and small amounts of molybdenum, silica, beryllium, boron and carbon. The aim of this study was to assess whether dental technicians are occupationally exposed to chromium, cobalt and nickel, by analyzing urinary excretion levels of these metals and to investigate the genotoxic effects of occupational exposure associated with dental prostheses production operations by analyzing cytokinesis-blocked micronucleus (CB-MN) frequencies in peripheral lymphocytes and micronucleus (MN) frequencies in exfoliated nasal cells from 27 dental laboratory technicians and 15 control subjects. The differences in the urinary excretion of metals between technicians and controls were statistically significant. The mean (±S.D.) CB-MN frequencies (‰) in peripheral lymphocytes were 4.00 (±2.98) among the dental technicians and 1.40 (±1.30) among the controls, a statistically significant difference (P<0.005). The mean (±S.D.) MN frequencies (‰) in nasal cells were 3.50 (±1.80) among the dental technicians and 1.19 (±0.53) among the controls, which was also a statistically significant difference (P<0.005). There was a significant correlation between duration of exposure and MN frequencies in lymphocytes (r=0.642, P<0.01), but not in nasal cells of technicians. Our data reveal that in vivo exposure to chromium, nickel and cobalt metals is evident and that this occupational exposure may contribute to the observed genotoxic damage in two types of cells, e.g. lymphocytes and exfoliated nasal cells. However, it cannot be determined which compound(s) are responsible for the genotoxic damage observed in this study.     

Evaluation of deleted in malignant brain tumors 1 (DMBT1) gene expression in bladder carcinoma cases: preliminary study

This study was undertaken to evaluate the expression of DMBT1 in bladder cancer and its correlation with clinico-pathological parameters analyzed in bladder carcinoma patients. We investigated DMBT1 in 56 paraffin embedded specimens of transitional cell carcinoma of the urinary bladder. We assessed DMBT1 gene expression at mRNA level by RT-PCR. Our results show 100% expression of DMBT1 in bladder carcinoma samples. Due to this preliminary results; gene expression was compared to tumor grade, and a significant difference was detected between grade 1 and 3 (p?=?0.028). The down-regulation of DMBT1 gene expression in carcinomas suggests the possible role in bladder cancer.     

Acantholimon doganii sp. nov. (Plumbaginaceae) with persistent circinnate leaf bases, from Turkey

The new species Acantholimon doganii Y. Bağcı, Doğu & Akaydın is described and illustrated. Diagnostic morphological characteristics in closely related species are discussed and the conservation status of the new species is analysed. A revised key to the Turkish Acantholimon species with persistent circinnate leaf basis is also provided.     

Plantar shear stress distributions: comparing actual and predicted frictional forces at the foot-ground interface

Plantar shear stresses are believed to play a major role in diabetic ulceration. Due to the lack of commercial devices that can measure plantar shear distribution, a number of mathematical models have been developed to predict plantar frictional forces. This study assessed the accuracy of these models using a custom-built platform capable of measuring plantar stresses simultaneously. A total of 48 (38 healthy and 10 diabetic) human subjects (75+/-20 kg, 41+/-20 years, 32 males, 16 females) were recruited in the study. Plantar force data were collected for 2s at 50 Hz. Two models (M1 and M2) reported in the literature by different groups were used to predict local shear stresses. Root mean squared errors (RMSE) were calculated to compare model data with the actual data, focusing on three parameters: location, magnitude and timing of peak shear components. RMSE values of estimated peak AP and ML shear locations were 3.1 and 2.2 cm for M1 and 3.1 and 2.1cm for M2, respectively. Magnitude RMS error values for M1 were found to be 86.6 kPa in AP shear and 38.5 kPa in ML shear, whereas these values were determined to be 97.8 and 63.5 kPa, respectively by M2. Time to peak shear RMSE values averaged 17.2% in terms of the gait duration. In conclusion, distribution of plantar shear should be measured rather than predicted, particularly if one is interested in the magnitudes of shear components.     

Effects of meteorin-like hormone on endocrine function of hypothalamo-hypophysial system and peripheral uncoupling proteins in rats

Molecular Biology Reports - Meteorin-like hormone (Metrnl) is a peptide secreted from the adipose tissue and modulates the whole-body energy metabolism. Metrnl release into the circulation is...     

A novel method for constructing an acellular 3D biomatrix from bovine spinal cord for neural tissue engineering applications

In this study, we aimed at generating 3-dimensional (3D) decellularized bovine spinal cord extracellular matrix-based scaffolds (3D-dCBS) for neural tissue engineering applications. Within this scope, bovine spinal cord tissue pieces were homogenized in 0.1 M NaOH and this viscous mixture was molded to attain 3D bioscaffolds. After resultant bioscaffolds were chemically crosslinked, the decellularization process was conducted with detergent, buffer, and enzyme solutions. Nuclear remnants in the native tissue and 3D-dCBS were determined with DNA content analysis and agarose gel electrophoresis. Afterward, 3D-dCBS were biochemically characterized in depth via glycosaminoglycan (GAG) content, hydroxyproline (HYP) assay, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Cellular survival of human adipose-derived mesenchymal stem cells (hAMSCs) on the 3D-dCBS for 3rd, 7th, and 10th days was assessed via MTT assay. Scaffold and cell/scaffold constructs were also evaluated with scanning electron microscopy and histochemical studies. DNA contents for native and 3D-dCBS were respectively found to be 520.76 ± 18.11 and 28.80 ± 0.20 ng/mg dry weight (n = 3), indicating a successful decellularization process. GAG content, HYP assay, and SDS-PAGE results proved that the extracellular matrix was substantially preserved during the decellularization process. In conclusion, it is believed that the novel decellularization method may allow fabricating 3D bioscaffolds with desired geometry from soft nervous system tissues.     

Comparison of infertility rates in communities from boron-rich and boron-poor territories

As a part of a large-scale work aimed at studying the health effects of boron (B) in residents of a country with the world’s largest supply, developmental effects of B are presented. Spontaneous abortions, stillbirths, and congenital malformations in addition to early infant mortality were questioned in the field by home visits. Although the number of families so far ascertained is rather small, the rates related to spontaneous abortions and stillbirths from high B exposure vs low B exposure subpopulations revealed no differences of significance, providing no evidence that B affects human development adversely.     

Stromal cell-derived factor-1-CXC chemokine receptor 4 interactions play a central role in CD4+ T cell accumulation in rheumatoid arthritis synovium

Rheumatoid arthritis (RA) is characterized by the accumulation of CD4(+) memory T cells in the inflamed synovium. To address the mechanism, we analyzed chemokine receptor expression and found that the frequency of CXC chemokine receptor (CXCR)4 expressing synovial tissue CD4(+) memory T cells was significantly elevated. CXCR4 expression could be enhanced by IL-15, whereas stromal cell-derived factor (SDF)-1, the ligand of CXCR4, was expressed in the RA synovium and could be increased by CD40 stimulation. SDF-1 stimulated migration of rheumatoid synovial T cells and also inhibited activation-induced apoptosis of T cells. These results indicate that SDF-1-CXCR4 interactions play important roles in CD4(+) memory T cell accumulation in the RA synovium, and emphasize the role of stromal cells in regulating rheumatoid inflammation.