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In foundries, various ores are used. Genotoxic assessment of ore-particles was the important aim of this study. In this regard, Ferrochromium, Ferrosilicon, Ferromanganese, and graphite were collected from an iron-casting industry. Also, the analysis has been performed by inductively coupled plasma optical emission spectroscopy (ICP-OES) and Fourier transform-infrared spectroscopy (FT-IR). The effective particle doses for A549-cells and genetic damages were evaluated using MTT and comet assay, respectively. The analysis indicated that, the samples contain Cr, Al, Cu, Fe, Mn, Zn, Ni, Pb, and SiO2. Ferrosilicon was known as the highest toxic ore. Ore particles significantly induced DNA breaks (p < 0.01) in a dose-dependent manner. A mixture of heavy-metals and silica in trace amounts caused genetic impairment. Moreover, the human health risk of the green–melting procedure is still notable in the casting industry. [ABSTRACT FROM AUTHOR]

Reteplase is a third generation tissue plasminogen activator (tPA) with a modified structure and prolonged half-life in comparison to native tPA. As a non-glycosylated protein, reteplase is expressed in Escherichia coli . Due to presence of several disulfide bonds, high level production of reteplase is complicated and needs extra steps for conversion to biologically active form. Auto-induction represents a method for high-yield growth of bacterial cells and higher expression of recombinant proteins. Here we have tried to optimize the auto-induction procedure for soluble and active expression of reteplase in E. coli . Results showed that using auto-induction strategy at 37 °C, Rosetta-gami (DE3) had the highest level of active and soluble reteplase production in comparison to E. coli strains BL21 (DE3), and Shuffel T7. Temperature dominantly affected the level of active reteplase production. Decreasing the temperature to 25 and 18 °C increased the level of active reteplase by 20 and 60%, respectively. The composition of auto-induction medium also dramatically changed the active production of reteplase in cytoplasm. Using higher enriched auto-induction medium, super broth base including trace elements, significantly increased biologically active reteplase by 30%. It is demonstrated here that auto-induction is a powerful method for expression of biologically active reteplase in oxidative cytoplasm of Rosetta-gami. Optimizing expression condition by decreasing temperature and using an enriched auto-induction medium resulted in at least three times higher level of active reteplase production. Production of correctly folded and active reteplase in spite of its complex structure helps for removal of inefficient and cumbersome step of refolding. [ABSTRACT FROM AUTHOR]

Context: Reactive oxygen species (ROS) are known to be one of the main causes of neurodegenerative disorders, and flavonoids play characteristic roles in a variety of biological activities, and specially are known to be antioxidant reagents. Objective: In this study, we investigated neuroprotective effects of digitoflavone to suppress H2O2-induced cell death in neuron-like PC12 cells. Material and methods: PC12 cells were pre-treated with digitoflavone for 2 h and then cells were exposed to H2O2for 18 h. The cells’ viability was evaluated by MTT assay. Rhodamine 123 staining was used for the determination of mitochondrial membrane potential (ΔΨm). The intracellular ROS aggregation was determined by using 2′,7′-dichlorofluorescein diacetate. Also, the level of mitochondrial biogenesis factors was measured by western blot. The antioxidant capacity of digitoflavone was also determined by measuring reduced glutathione (GSH) level and catalase (CAT) activity quantification. Results: Digitoflavone significantly elevated cells’ viability at concentrations of 10 and 20 µM. Also, digitoflavone attenuated intracellular level of ROS, and stabilized ΔΨm. Moreover, digitoflavone increased phosphorylation of AMP-activated protein kinase (AMPK) and, consequently, elevated mitochondrial biogenesis factors which were reduced after H2O2exposure. We emphasized on the protective effect of digitoflavone through increasing mitochondrial biogenesis by specifically inhibiting AMPK. Antioxidant ability of digitoflavone was indicated by the elevation of GSH level and CAT activity. Conclusion: As a result, digitoflavone stabilize ΔΨm, enhanced cell viability through inducing mitochondrial biogenesis pathway, and increased antioxidant capacity of the cells which lead to better combating the oxidative stress. [ABSTRACT FROM AUTHOR]

Background: Borna disease virus (BDV) is an evolutionary old RNA virus, which infects brain and blood cells of humans, their primate ancestors, and other mammals. Human infection has been correlated to mood disorders and schizophrenia, but the impact of BDV on mental-health still remains controversial due to poor methodological and cross-national comparability. Method: This first report from the Middle East aimed to determine BDV infection prevalence in Iranian acute psychiatric disorder patients and healthy controls through circulating immune complexes (CIC), antibodies (Ab) and antigen (pAg) in blood plasma using a standardized triple enzyme immune assay (EIA). Samples of 314 subjects (114 psychiatric cases, 69 blood donors, and 131 healthy controls) were assayed and data analyzed quantitatively and qualitatively. Results: CICs revealed a BDV prevalence of one third (29.5%) in healthy Iranian controls (27.5% controls; 33.3% blood donors). In psychiatric patients CIC prevalence was higher than in controls (40.4%) and significantly correlating with bipolar patients exhibiting overt clinical symptoms (p = 0.005, OR = 1.65). CIC values were significantly elevated in bipolar (p = 0.001) and major depressive disorder (p = 0.029) patients as compared to controls, and in females compared to males (p = 0.031). Conclusion: This study supports a similarly high prevalence of subclinical human BDV infections in Iran as reported for central Europe, and provides again an indication for the correlation of BDV infection and mood disorders. Further studies should address the morbidity risk for healthy carriers and those with elevated CIC levels, along with gender disparities. [ABSTRACT FROM AUTHOR]

Introduction: Brain-Derived Neurotrophic Factor (BDNF) and its receptor, TrkB, in the hippocampus are targets for adverse effects of stress paradigms; in addition, BDNF and its receptor play key role in the pathology of brain diseases like depression. In the present study, we evaluated the possible role of hippocampal BDNF in depression during pregnancy, Methods: To achieve the purpose, repeated restrain stress (1 or 3 hours daily for 7 days) during the last week of pregnancy was used and alteration in the gene expression of hippocampal BDNF and TrkB evaluated by semi-quantitative PCR. Results: The results showed that in stress group the level of ACTH and Corticosterone is increased showing that our model was efficient in inducing psychological stress; we also found that BDNF and TrkB expression are decreased in 3 hours stress group but not in 1 hour stress compared to control group. Discussion: Our results imply that decrease in BDNF and its receptor could contribute in some adverse effects of stress during pregnancy such as elevation of depressive like behavior. [ABSTRACT FROM AUTHOR]

Human Interferon β (INF-β) is a member of cytokines family which different studies have shown its immunomodulatory and antiviral activities. In this study an expression vector was designed and constructed for expression of human INF-β-1b either in shake flasks or bench top bioreactor. The designed vector was constructed based upon pET-25b(+) with T7 promoter. Recombinant human beta interferon (rhINF-β) was codon optimized and overexpressed as a soluble, N-terminal pelB fusion protein and secreted into the periplasmic space of Escherichia coli BL21 (DE3). The sugar, Isopropyl-β-D-thiogalactopyranoside (IPTG) was used as a chemical inducer for rhINF-β production in the shake flasks and bench top bioreactor. Timing of beta interferon expression was controlled by using the T7 promoter. The rhINF-β protein was extracted from periplasmic space by osmotic shock treatment and the expression of the beta interferon encoding gene in random selected transformants, was confirmed by western and dot blot methods. The maximum of product formation achieved at the OD600nm = 3.42 was found to be 35 % of the total protein content of the strain which translates to 0.32 g L-1. The constructed vector could efficiently overexpress the rhINF-β into the periplasmic space of E. coli. The obtained yield of the produced rhINF-β was more than previous reports. The system is easily adapted to include other vectors, tags or fusions and therefore has the potential to be broadly applicable to express other recombinant proteins. [ABSTRACT FROM AUTHOR]

Tuning recombinant protein expression is an approach which can be successfully employed for increasing the yield of recombinant protein production in high cell density cultures. On the other hand, most of the previous results reported the optimization induction conditions during batch and continuous culture of recombinant E. coli, and consequently fed-batch culture have received less attention. Hence, in this research induction conditions for the over-production of recombinant interferon-γ including the amount of inducer, induction time and post-induction duration during chemical induction were optimized. E. coli BL21 (DE3) (pET3a-hifnγ) was used to over-express human interferon-gamma (hIFN-γ) in an exponential fed-batch procedure with a maximum attainable specific growth rate of 0.55 h-1 at the beginning of feeding and 0.4 h-1 in induction time. The factors were considered as the amount of inducer (IPTG) in the range of 0.565-22 mg g-1 L-1 at seven levels, cell density at induction time as 53, 65 and 75 g (dry cell weight) L-1, induction duration at different intervals of 3, 4, and 5 h after induction time. The final concentration of biomass and interferon gamma reached to 127 g L-1 (DCW) and 51 g (hIFN-γ) L-1 after 17 h, and also the final specific yield and overall productivity were obtained 0.4 g (hIFN-γ) g-1 DCW and 3 g (hIFN-γ) L-1 h-1, respectively, which are the highest amounts of reported specific yield and productivity for recombinant proteins production. [ABSTRACT FROM AUTHOR]

Abstract: Enteroviridae such as coxsackievirus are important infectious agents causing viral heart diseases. Viral protease 2A (2Apro) initiates the virus life cycle, and is an excellent target for developing antiviral drugs. Here, to evaluate the validity of the 2Apro as a proper therapeutic target, and based on the existing information and molecular dynamics, a 16-mer peptide was designed to specifically target the active site of protease 2Apro in order to block the activity of CVB3 2Apro. We showed that the peptide could compete with endogenous substrate in a concentration-dependent manner. Further, we established a HeLa cell line that expressed 2Apro. Expression of 2Apro resulted in significant morphological alteration and eventual cell death. Western blot and viability assay showed that the 16-mer peptide (200 μg/ml) could significantly block 2Apro activity and its cytotoxic effect. Future modification of the 16-mer peptide can improve its affinity for 2Apro and therefore develop effective antiviral drug. [Copyright &y& Elsevier]

Abstract: Alzheimer''s disease (AD) a progressive neurodegenerative disorder of later life, is characterized by brain deposition of amyloid β-protein (Aβ) plaques, accumulation of intracellular neurofibrillatory tangles, synaptic loss and neuronal cell death. There is significant evidence that oxidative stress is a critical event in the pathogenesis of AD. In the present study Aβ formation was induced in NT2N neurons, one of the most appropriate cell line models in AD. Our results indicate that oxidative stress resulting from the treatment of H2O2/FeSO4 and/or 4-hydroxy-2-noenal (HNE) can be inhibited in the presence of tBHQ, a known inducer of nuclear factor-erythroid 2 related factor 2 (Nrf2) in NT2N neurons and can therefore be used to elucidate the relationship between oxidative stress, Aβ formation and Nrf2. The role of Nrf2 was confirmed using retinoic acid as an inhibitor of Nrf2. It provides the first documentation that tBHQ not only protects the neurons against cell death but also decreases amyloid β formation. Moreover, the results indicate that oxidative stress fosters Aβ formation in NT2N neurons, creating a vicious neurodegenerative loop. [Copyright &y& Elsevier]

Corticosterone induces neuroanatomical and neurochemical changes in the hippocampus that are associated with cognitive impairments. In the present study corticosterone induced cell death in primary hippocampal neurons cultured in Neurobasal + B27 medium. Insulin prevents neuronal cell death induced in a concentration dependent manner. The neuroprotective effect of insulin was reversed by LY294002, a phosphatidylinositol 3′-kinase (PI3 kinase) inhibitor, whereas the mitogen-activated protein kinase (MAPK) inhibitor PD98059, an upstream blocker of MAPK had no effect. Western blot analyses showed that insulin induced the activation of protein kinase B (Akt). These results suggest that insulin can prevent neuronal cell death induced by corticosterone in hippocampal neurons by modulating the activity of the PI3 kinase/Akt pathway. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Abstract: Reported here is the overexpression, purification and partial characterization of recombinant coxsakievirus B3 2A protease (CVB3 2Apro) from bacterial cells transformed with a plasmid containing the CVB3 2Apro cDNA sequences. The structural investigation showed that the protein contains mostly β-strand elements and requires Zn2+ ions as a structural component which appeared to be inhibitory if added exogenously. The purified enzyme activity was optimal at 4°C and had a short half-life at physiological temperature. This feature can be the result of the presence of a high content of β-structure and also hydrophobic residues in its structure. [Copyright &y& Elsevier]

Background: There is no cell line susceptible to hepatitis D virus (HDV) infection and capable of stable replication of its genome. Different genetic-based approaches have been introduced to initiate HDV replication events so far. Methods: In order to construct a replicative model for HDV made from a unique genome sequence, two monomeric units of HDV full-length cDNA were joined together through a four-step cloning scheme. The resulting vector (pcDNA3.1-D2) containing two tandem repeats of HDV cDNA under CMV promoter control was then used in transfection experiments into COS7 and HuH7 cell lines. Results: HDV replication markers including expression of hepatitis δ antigen (HDAg), the only HDV-specific antigen, and synthesis of antigenomic RNA were shown in both transfected cell lines, indicating initiation of HDV genome replication. Conclusions: Our results suggested that pcDNA3.1-D2, a vector containing a cDNA dimer of the HDV genome, originated from a unique full-length HDV molecule that is capable of replicating in cultured cells. This vector can be used conveniently for transfection experiments to study HDV molecular biology. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Intracerebroventricular (ICV) administration of streptozotocin (STZ) has been used as a metabolic model of sporadic Alzheimer's disease (AD). Erythropoietin (EPO) possesses neuroprotective and memory‐improving effects, which might be advantageous in treating different characteristics of AD. Nevertheless, the hematopoietic effect of EPO has hindered its application as a neuroprotective agent. Previous studies have shown that a new Epo derivative called carbamylated Erythropoietin‐Fc (CEPO‐Fc), yield noticeable neuroprotective effects without affecting hematopoiesis. In this study, the neuroprotective effects of CEPO‐Fc on icv‐STZ induced memory impairment and hippocampal apoptosis were examined. Method: Adult male Wistar rats weighing 250‐300 g were used. STZ was administered on days 1 and 3 (3 mg/kg in divided doses/icv), and CEPO‐Fc was administered at the dose of 5000 IU/ip/daily during days 4‐14. The animals were trained in Morris water maze during days 15‐17, and the memory retention test was performed on the 18th day. Following behavioral studies, the animals were sacrificed and their hippocampi isolated to determine the amounts of cleaved caspase‐3 (the landmark of apoptosis). Result: The results showed that CEPO‐Fc treatment at the dose of 5000 IU/kg/ip was able to prevent the learning and memory deficit induced by icv‐STZ. Western blot analysis revealed that STZ prompted the cleavage of caspase‐3 in the hippocampus while pretreatment with CEPO‐Fc significantly reduced the cleavage of this protein. Conclusion: Collectively, our findings suggest that CEPO‐Fc could restore STZ‐induced learning and memory impairment as well as apoptosis in the hippocampal region in a rat model of sporadic AD induced by icv‐STZ. [ABSTRACT FROM AUTHOR]