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We have investigated the mechanism of shikonin function on protection of dopaminergic neurons against 6-OHDA-induced neurotoxicity. Treatment of rat pheochromocytoma cell line PC12 by serial dilutions of shikonin determined 10 μM of the compound as its optimum concentration for protection saving nearly 70 % of the cells against toxicity. Reverse transcription-PCR analysis of shikonin-treated cells showed threefold increase in mRNA levels of glutathione peroxidase-1 (GPX-1) as a representative component of the intracellular anti-oxidant defense system. To elucidate shikonin-GPX1 relationships and maximize protection, we transduced PC12 cells using recombinant lentivirus vectors that harbored GPX-1 coding sequence. This change upregulated GPX-1 expression, increased peroxidase activity and made neuronal cells resistant to 6-OHDA-mediated toxicity. More importantly, addition of shikonin to GPX1-overexpressing PC12 cells augmented GPX-1 protein content by eightfold leading to fivefold increase of enzymatic activity, 91 % cell survival against neurotoxicity and concomitant increases in intracellular glutathione (GSH) levels. Depletion of intracellular GSH rendered all cell groups highly susceptible to toxicity; however, shikonin was capable of partially saving them. Subsequently, GSH-independent superoxide dismutase mRNA was found upregulated by shikonin. As signs of apoptosis inhibition, the compound upregulated Bcl-2, downregulated Bax, and prevented cell nuclei from undergoing morphological changes typical of apoptosis. Also, a co-staining method demonstrated GPX-1 overexpression significantly increases the percent of live cells that is maximized by shikonin treatment. Our data indicate that shikonin as an antioxidant compound protects dopaminergic neurons against 6-OHDA toxicity and enhances their survival via both glutathione-dependent and direct anti-apoptotic pathways.

Electrified interfaces have been used to produce fine particles. Here, we investigate the behavior of planar electrified interface in the presence of vertical electric field. Corn oil and four KCl aqueous solutions with different concentrations are employed. During the experiments, for the first time, four distinct behaviors of electrified interfaces were disclosed and named as: Hump figure of interface, Taylor cone appearance and its rotary motion on the interface, intermittent jetting and thorough ascending of the interface. Taylor cones' mean droplet diameter and their angles, discharging velocity at the tip of the cone, the frequency of Taylor cones appearance, and their merging to each other are studied in this paper. Additionally, the circumstances of interface levitation affected by electric field are some of the major results of this study to gain some insight into the electrified interfaces issue., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Background: Anthropometry is the biologic science of human body measurement. Craniofacial anthropometry discusses the characteristics on the measures of different soft and hard tissues of the head and face, and it is considered an important paraclinical record for the growth and development of the index and also for the diagnosis and curing orthodontic matters. Studying the craniofacial anthropometrics ratios is very useful in sciences such as dentistry, medicine, maxillofacial surgery, growth and development studies, plastic surgery, bioengineering, and nonmedical branches such as respiratory equipment and eye-glasses industries., Objectives: The aims of this study were to determine Iranian cranial and facial anthropometric ratios and compare anthropometric ratios between Iranian and Canadian populations., Methods: This cross-sectional analytical study was done randomly on 564 four-to-eleven-year-old boys from Shirvan (North Khorasan, Iran) with normal face patterns. Facial and cranial ratios were estimated and compared. Data were analyzed by SPSS software. The mean values of these parameters were calculated .Finally, the regression line and the growth coefficient were determined for each parameter. Furthermore, the mean anthropometric measurement of Iranians was compared with Canadians. Student t test was used for comparing the measured values., Results: Iranian population when born has hypereuryprosopic face and hypercephalic cranium form. While getting older, the midface height increases, face becomes more prominent, chin becomes shorter, and the face and cranium change to eurycephalic and hyperleptoprosopic form, respectively. Comparison of results related to the face and cranium size between Iranian and Canadian boys (4-11 years old) showed that many craniofacial ratios have significant differences (P < 0.05)., Conclusions: Approximately, all of the anthropometric measurements in Iranian population and Canadians were significantly different. Considering the significant difference in the facial and cranial anthropologic ratios and size among Iranians and Canadians, the results obtained from Canadians should not be applied as criteria for treatment plans. Because of the wide population affinity combinations in Iran, more studies, with wider variations, should be conducted among different Iranian population affinity.