Journal of Sciences, Islamic Republic of Iran
Year:2005 | Volume:16 | Issue:2|Papers Count:18

Hemophilia A is an X-linked recessive bleeding disorder, widely prevalent throughout the world, for which, replacement therapy is a current treatment done by infusion of either human plasma derived FVIII or recombinant FVIII. In order to produce a recombinant form of biologically active human coagulation factor VIII, a mammalian expression system is necessary for proper post-translational modifications. In this regard, two types of mammalian cell lines, COS7 and CHO, were transfected with a recombinant plasmid, constructed by insertion of a NotI restriction fragment containing B-domain-deleted cDNA of hFVIII in pcDNA3 plasmid, downstream of CMV promoter. By performing one-stage clotting assay as well as ELISA test on the conditioned media collected from transfected cells, we confirmed transient and stable expression of rhFVIII in the transfected COS7 and CHO cells, respectively. The presence of rhFVIII mRNA was also demonstrated by performing RT-PCR on total cellular RNA, extracted from the stably transfected CHO cells. The highest amount of produced active rhFVIII in the stably transfected CHO cells was estimated to be around 0.1 U/ml of the cultured media. By applying southern blotting experiment on the digested as well as high molecular weight chromosomal DNA, prepared from the stably transfected CHO cells, we have demonstrated the presence of the rhFVIII expressing plasmid in the CHO cells. The recombinant plasmid as well as the stable FVIII expressing cell line developed in this study has provided useful bases for further molecular studies of various important factors influencing the expression efficiency of rhFVIII.

Drinking water is the fastest and most direct form of nitrate consumption by the population. High concentrations of nitrate in drinking water can be hazardous to health, especially for infants and pregnant women. Nitrate contamination of drinking water is endogenously reduced to nitrite and subsequent nitrosation reactions give rise to carcinogenic N-nitroso compounds. The objective of this study was to determine the quantities of NO3 - in the consuming drinking water in Isfahan. In this study, 513 water samples were collected from different houses from municipalities of three different zones of Isfahan. Each house was sampled five times during July, August and September of 2004. The average Nitrate concentration for the total samples was 22.8 ± 10.4 mg/L. Nitrate concentrations ranged from 6.6 to 63.5 mg/L. Nitrate concentrations exceeded the maximum contaminant level of 45 mg/L in 19 water samples (3.7%), whereas 332 samples (64.7%) had nitrate concentrations of less than 25 mg/L. There was a significant difference between three zones for monitoring nitrate with averages 16.4 ± 4.9, 18.7 ± 8.9 and 31.2 ± 8.7 mg/L for zone 1, 2 and 3 respectively. Based on results of this study, with one unremarkable exception, the nitrate levels found in the water analyzed were optimum for human consumption and complied with WHO and current European Legislation.

Although the application of biodegradative genetically engineered micro organisms (GEMs) for bioremediation is very promising, the risks of their release should be assessed before their introduction into the environment. Lux-marked Ralstonia eutropha H850Lr (formerly Alcaligenes eutrophus H850Lr) was introduced into sterile and non-sterile soil microcosms at matric potentials -2.11, -30, -750, and -1500 kPa. Viable cell concentration and luminescence activity of R. eutropha H850Lr was measured by plate counting and luminometry respectively. R. eutropha H850Lr could survive better in non-sterile soil at -30 kPa than other matric potentials. Luminescence values were closely related to viable cell concentrations indicating the usefulness of a Bioluminescence-marker system for tracking the above bacterium in the environment. Statistical analysis showed a significant effect of matric potential on viable cell concentrations. The luminescence activities in the soil environment emphasize that these factors should be considered during application of GEMs in the natural environment.

Herpes Simplex Virus Type 1 (HSV-1) is a member of the Herpesviridae family that causes herpetic disease in human. During the last 25-30 years, many investigations have been conducted on pathogenesis and molecular biology of this virus in several countries. In Iran HSV-1 has been isolated from patients and detected using immunological techniques. In this study, we investigated the molecular aspects of two Iranian isolated viruses by PCR-RFLP of HSV-1 DNA Polymerase gene. The result of Southern blot hybridization indicated that the Iranian isolates are HSV type 1. Moreover, the restriction pattern of the Iranian isolates is different from the KOS strain for DpnI enzyme. It is proposed to use this difference as a molecular marker of the Iranian strain.

Rifampin interacts with the beta-subunit of RNA Polymerase (rpoB), thereby hindering transcription. Mutations in the rpoB locus confer conformational changes leading to defective binding of the drug to rpoB and consequently resistance. Polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) and direct sequencing have been established as a rapid screening test for the detection of mutation in rpoB gene, which is responsible for rifampin resistance of Mycobacterium tuberculosis species. In this study, a total of 37 strains of M. tuberculosis, 16 sensitive and 15 resistant of Isfahan isolates, and 6 resistant strains obtained from Pasteur institute of Iran, were used. They were confirmed as M. tuberculosis by conventional methods and amplification of DR gene a region that belongs to M. tuberculosis complex group. Their sensitivity or resistance to Rifampin was initially determined by proportion method. The 193-bp region of the rpoB gene was then amplified and PCR-SSCP patterns of rifampin resistance (RIFr) and rifampin susceptible (RIFs) strains were determined by electrophoresis on 10% acrylamide gels and silver staining. Also 8 samples of 193-bp rpoB amplicons with different PCRSSCP patterns from Rifr and one from Rifs were sequenced. By PCR-SSCP analysis, 7 PCR-SSCP distinguishable patterns were recognized in the Isfahan RIFr strains. Although 6 of these patterns were different from sensitive strain, one pattern was identical to sensitive standard strain H37Rv. Six resistant strains from Pasteur institute of Iran demonstrated two patterns that one of them was alike to pattern 4 of Isfahan RIFr but other was different. 15 out of 16 RIFs isolates demonstrated PCR-SSCP banding patterns similar to that of sensitive standard strain H37Rv. However, one of the sensitive isolates demonstrated different pattern. After determinations the rpoB sequences of the resistance strains, different mutations were seen in codon 523(GGG/GGT), 526(CAC/TAC), 531(TCG/TTG) and 511(CTG/TTG). This study demonstrated the high specificity (93.8%) and sensitivity (95.2%) of PCR-SSCP method. Presence of different PCR-SSCP banding patterns that were observed in this study is in accordance with the results of similar studies in other parts of the world. The two most prevalent mutations were missense mutations at the positions Ser-531 (TCG/ TTG: Ser/Leu) and His-526 (CAC/TAC: His/Tyr). This finding is comparable to the results of early studies demonstrating the rpoB mutation frequencies in isolates from other parts of the world.

2-Phenyl-1-(3",5" -dichloro-2"-benzo(b)thiophenoylamino)-4-arylidine-5- imidazolones (2a-j) were prepared from the 2-hydrazinocarbonyl-3,5- dichlorobenzo[b]thiophene 1 by the reaction with different oxazolinone which were prepared by the condensation of substituted benzaldehyde with benzoyl glycine in presence of sodium acetate and acetic anhydride. Reaction of 1 with different aromatic isothiocyanate afforded the corresponding N1-(3",5"- dichlorobenzo[b]thiophen-2"-y1)-N4-substituted aryl thiosemicarbazides (3a-j). Compounds (3a-j) on reaction with sodium hydroxide yielded 3-(3",5"- dichlorobenzo[b]thiophen-2"-y1)-4-aryl-5-mercapto-1,2,4-triazoles (4a-j). The pharmacological evaluations were performed for their antitubercular and antimicrobial activities. Some novel imidazolones and 1,2,4-triazoles were synthesized and evaluated for in vitro antibacterial activity against Escherichia coli ATCC 25922, Proteus vulgaris ATCC 6380, Bacillus megaterium ATCC 14581, Staphylococcus aureus ATCC 29213, and antifungal activity against Aspergillus niger ATCC 9029. The in vitro antimycobacterial activity of the new compounds was also investigated against Mycobacterium tuberculosis H37RV (ATCC 27294) in BACTEC 12B medium using the ALAMAR radiometric system. The structures of new compounds were supported by IR, 1H-NMR and Mass spectral data.

A series of 2-(4-nitro-1-imidazolylmethyl)-1,3,4-oxadiazole, 1,3,4-triazole and 3-(4-nitro-1-imidazolylmethyl)-1,2,4-triazole derivatives were synthesized and tested for their antimicrobial activity. Some of the tested compounds were active against Staphylococcus aureus, Staphylococcus epidermidis, Bacillus subtilis, Clostridium difficile, Aspergillus niger and Cryptococcus neoformans.

Qaleh-Zari is a Fe-oxide Cu-Ag-Au vein type deposit located 180 km south of Birjand, in  eastern Iran. Host rocks are mainly Tertiary calc-alkaline to K-rich calc-alkaline with transition to shoshonitic andesite and andesitic basalts, but in the central part shale and sandstone of Jurassic age. Andesitic rocks from the western region of Qaleh-Zari were dated to 40.5 ± 2 Ma. Four trends of faults and joints are identified in the mine area. Cu-Ag-Au mineralization is present only in the oldest sets of faults and joints that crosscut the Tertiary and Jurassic units. Three major subparallel steep quartz veins are identified. No.1 vein is about 650 m long and No.3 vein is less than 500 m long. No.2 vein is traced for more than 3.5 km horizontally along strike (N40° W) and more than 350 m down dip. Specularite and quartz are the most abundant primary oxides. Chalcopyrite is the only hypogene copper mineral. Silver is present as sulfosalt minerals. Paragenesis: Stage I: specularite, quartz, Fe-chlorite, chalcopyrite and sulfosalts. Specularite deposited first and forms 10 to 25 percent of the vein. Stage II: quartz, chalcopyrite, pyrite, chlorite ± hematite ± sulfosalt minerals. Stage III: quartz ± pyrite ± chalcopyrite. Stage IV: hematite, quartz, and ± calcite. The ores grade typically 2-9% Cu, 100-650 ppm Ag, and 0.5-35 ppm Au. Homogenization temperatures of fluid inclusions associated with Cu, Ag, and Au deposition were varying between 360°C and 240°C. The salinity of the fluid was between 1 to 6 wt % NaCl equiv and the CO2 content was low (less than 1 mole %). The δ34SCDT values of pyrite and chalcopyrite were between 0.4 to 2.2‰, which was consistent with a magmatic-hydrothermal or leached volcanic source. The δ13CPDB values of calcite were between 16.9 to 17.4‰ and the calculated δ13CPDB of the fluid is between −3.8 and −3.0‰. The δ18OSMOW of the carbonates were between 16.96 and 19.40‰. Calculated fluid δ18OSMOW values were 7.4 to 9.8‰, which overlapped the range of magmatic water. The C and O isotopic values of calcite were similar to porphyry copper deposits, possibly indicating magmatic affinities for the ore fluids. Based on the presence of hematite, chalcopyrite, Fe-rich chlorite and locally pyrite, and on the absence of magnetite and pyrrhotite, the ore fluid was very oxidized. Oxygen fugacity was estimated to have been between 10−27 and 10−32, and the fugacity of H2S was less than 10−3.5.

A parallel algorithm for generating t-ary tree sequences in reverse B-order is presented. The algorithm generates t-ary trees by 0-1 sequences, and each 0-1 sequences is generated in constant average time O(1). The algorithm is executed on a CREW SM SIMD model, and is adaptive and cost-optimal. Prior to the discussion of the parallel algorithm a new sequential generation with O(1) average time complexity, and ranking and unranking algorithms with O(t n) time complexity is also given.

Very smooth thin films of iridium have been deposited on super polished fused silica (SiO2) substrates using dc magnetron sputtering in argon plasma. The influence of deposition process parameters on film micro roughness has been investigated. In addition, film optical constants have been determined using variable angle spectroscopic ellipsometery, over the spectra range from vacuum ultraviolet to middle infrared (140 nm-35 μm) Also the surface roughnesses were measured by atomic force microscopy (AFM).