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Hassan S.,Research Institute for Environmental science | Daryoush A.,Research Institute for Environmental science | Sadegh O.M.,Research and Technology
African Journal of Microbiology Research | Year: 2011

Bioremediation is a simple and effective technology for metal extraction from low-grade contaminated soils and mineral concentrates. Metal remove from sulfide minerals is based on the activity of mesophilic and chemolithotrophic bacteria, mainly Acidithiobacillus ferrooxidans which convert insoluble metal sulfides into soluble metal sulfates. In this study bioremediation experiments carried out in 1 L Erlenmeyer flasks containing 300 ml basal medium of A. ferrooxidans and 5% (w/v) PbS with 45 and 75 meshes and also this condition repeated for Acidithiobacillus thiooxidans. The results showed that A. ferrooxidans had grown on the galena and obtained energy from it. Also, the galena was oxidized to form lead sulfate. The most important species for oxidizing galena concentrate showed A. ferrooxidans, because these species were more effective than A. thiooxidans in our bioremediation experiments. Anglesite (PbSO4) was the important product of the galena bacterial oxidation. In these experiments the highest quantity of dissolute lead was 34% approximately in A. ferrooxidans cultures. The low solubility of lead sulphate indicated that this process is not commercially feasible for the recovery of lead on mines. In view of these results, bioremediation appears to have some potential for remediation of Pb contaminated soils. © 2011 Academic Journals.

Ebrahimi B.,Research Institute for Environmental science | Ebrahimi B.,Shahid Bahonar University of Kerman | Yaghoobi M.M.,Research Institute for Environmental science | Nejad M.A.,Shahid Bahonar University of Kerman | And 2 more authors.
Yakhteh | Year: 2010

Objective: The objective of this study was to isolate and culture human dental pulp stem cells to study important stem cell markers in them. Materials and Methods: Dental stem cells were isolated from human pulp and cultured in alpha-modified eagle's medium (α-MEM) supplemented with 20% fetal bovine serum (FBS) in a 37°C incubator with 5% CO2 and photographed under inverted microscope. The expressions of the important stem cell markers were analyzed by reverse transcription polymerase chain reaction (RT-PCR) and agarose gel electrophoresis in the cells at different passages. Results: Cells isolated from dental pulp showed a high rate of proliferation and were cultured to more than 15 passages in vitro. The study of gene expression by RT-PCR showed that these cells expressed nucleostemin, cyclin D1, Oct-4 and nanog (major components of the PluriNet) in different passages as well as under serum-free conditions. Conclusion: Cells isolated from dental pulp are genuine pluripotent stem cells with high potential for self-renewal. The expression of the stem cell markers in human dental pulp stem cells indicate that they have a great potential for cell therapy and regenerative medicine, even they were isolated from adult teeth.

Nejad A.L.,Research Institute for Environmental science | Yaghoobi M.M.,Research Institute for Environmental science
Iranian Journal of Basic Medical Sciences | Year: 2012

Objective(s) P53 is an important tumor suppressor, which is mutated in later stages of many cancers and leads to resistance to chemotherapy. The aim of this study was to reveal mutations of TP53 in colorectal cancer in Kerman province. Materials and Methods A total of Forty-three colon cancer specimens as paraffin block or fresh tissues, which passed stage IIIA, were selected. Three exons 5, 7 and 8 of P53 were amplified by PCR technique and sequenced directly. Results The results showed two deletions at codon 140 and 142 in one tumor sample. GAT→AAT mutation at codon 184, and CGG→TGG mutation at codon 248 were seen in some tumor samples. Some mutations were also observed in middle of intron 7 in some tumor or normal tissues. Conclusion Some of those patients with mutation in P53 gene had metastasis in other organs. Therefore, genetic test before chemotherapy is helpful for successful treatment.

Nabiabad H.S.,Tarbiat Modares University | Nabiabad H.S.,Research Institute for Environmental science | Yaghoobi M.M.,Research Institute for Environmental science | Javaran M.J.,Tarbiat Modares University | Hosseinkhani S.,Tarbiat Modares University
Preparative Biochemistry and Biotechnology | Year: 2011

Recombinant tissue-type plasminogen activator (rt-PA) has been produced in different hosts. In this research, transgenic tobacco was selected for production of human rt-PA. Transgenic plants were analyzed by polymerase chain reaction (PCR) and reverse-transcription (RT)-PCR. The protein was extracted by Lysine Sepharose chromatography column and was further purified by HiTrap desalting column. The function of eluted protein was analyzed on zymography gel. The results showed that the 1.7-kb cDNA of tissue-type plasminogen activator (t-PA) (as well as a shortened 650-bp transcript of t-PA) has been expressed in transgenic plants. The anticipated 63-kD protein band and an additional 53-kD protein were observed in transgenic plants. Finally, zymography assay revealed that the purified rt-PA has anticipated appropriate activity comparable to a positive control drug (Alteplase). On the whole, we can say that transgenic tobacco is a good alternative host for production of t-PA. Copyright © Taylor & Francis Group, LLC.

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