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Biomacromolecular Journal - Volume:2 Issue: 1, Summer 2016

Biomacromolecular Journal
Volume:2 Issue: 1, Summer 2016

  • تاریخ انتشار: 1395/07/11
  • تعداد عناوین: 7
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  • Gabor Somlyai*, Behnam Javaheri, Hadi Davari, Zolt, Aacute, N. Gy, Ouml, Ngyi, Ildik, Oacute, Somlyai, Kirk A. Tamaddonl., Aacute, Szl, Oacute, G. Boros Pages 1-7
    The two stable isotopes of hydrogen, protium (1H) and deuterium (2H) differ in their physicochemical nature. Deuterium-depleted water (DDW) significantly inhibited the growth rate of different tumor cell lines in culture media and xenotransplanted MDA-MB-231, MCF-7 human breast adenocarcinomas and PC-3 human prostate tumors in vivo. The apoptosis-triggering effect of DDW was demonstrated both in vitro and in vivo. The anti-cancer effect of D-depletion was also confirmed in a double-blind, randomized, 4-month-long, human phase II clinical trial on prostate cancer. D-depletion, as an adjuvant, caused 3-7 fold increases of median survival time (MST) in lung cancer, two-fold in advanced breast cancer and it also effectively prevented recurrences of early stage breast cancer. It is suggested that the cell cycle regulating system is able to recognize the changes in the 2H/1H ratio. Two key events takes place in the cell at the same time: the binding of growth hormone to the receptor activates the H+transport system, which preferentially eliminates H, resulting in an increased 2H/1H ratio, which is essential to start cell division; the properly working mitochondria, the terminal complex of mitochondrial electron transport chain reducing molecular oxygen to DDW, which reduces the 2H/1H ratio and inhibits the cell growth. The balance between the activated H+transport system and the DDW producing mitochondria which determine the 2H/1H ratio in the cells is proposed as the key mechanism to regulate cell growth.
    Keywords: Deuterium depleted water, DDW, Cell growth, Clinical, Cancer
  • Neda Assari, Seiedabdolmajid Angaji *, Saeed Morovvati Pages 8-14
    Urokinase might play a role in the formation of kidney stones. This study was done to determine the association between  T/C polymorphism at the 3′-untranslated region of urokinase gene and calcium kidney stones. This Case-Control study was carried out on 70 cases with a history of calcium kidney stones and 70 controls from the Baqiyatallah hospital of Tehran in 2013. The study of polymorphism was performed by Allele-specific PCR method. Mutant T allele frequency was %41 in cases and %18 in controls. Hardy-Weinberg equilibrium (HWE) was tested using chi-square test. The chi-square showed that the control population is in HWE, and as expected, the patient group does not follow HWE. The odds ratio for the risk of the T allele was 1.7 (%95 confidence interval 0.2988-1.158). A significant association was found between the urokinase gene T/C polymorphism and the formation of calcium kidney stones. Also, effect modification was examined for both sexes and different age groups. According to the results, T polymorphism in the 3’-UTR of urokinase gene may increase with age.
    Keywords: Single nucleotide polymorphism, 3', Untranslated region, AS, PCR, Hardy, Weinberg equilibrium
  • Rezvan Kohzadi, Ahmad Molaeirad*, Mahdi Alijanianzadeh, Nasrin Kamali, Mansour Mohtashamifar Pages 15-20
    A label-free electrochemical nucleic acid aptasensor for the detection of methamphetamine (MA) by the immobilization of thiolated self-assembled DNA sequences on a gold nanoparticles-chitosan modified electrode is constructed. When MA was complexed specifically to the aptamer, the configuration of the nucleic acid aptamer switched to a locked structure and the interface of the biosensor changed, resulting in a variation of the corresponding peak current of an electrochemical probe ([Fe(CN)6]3-/4-). Two different methods of cyclic voltammetry (CV) and microcantilever were employed to determine MA detection limit. Under the optimized experimental conditions, the presented sensor exhibits a nice specificity towards MA. The detection limits for MA in electrode and microcantilever were obtained 10 and 0.7 nM. The proposed aptasensor can be easily regenerated by the denaturalization of aptamer-target complexes in a heated water bath at 80-90 °C. Besides, this biosensor has a high reproducibility and selectivity, which can be a promising method to detect MA in real samples.
    Keywords: Aptasensor, Methamphetamine, Detection limit
  • Elham Mozaffari, Elham Tazikeh, Lemeski*, Ali Akbar Saboury Pages 21-30
    Human serum albumin (HSA) is the most abundant protein in the blood plasma. Drug binding to HSA is crucial to study the absorption, distribution, metabolism, efficiency and bioavailability of drug molecules. In this study, isothermal titration calorimetry and molecular dynamics simulation of HSA and its complex with indometacin (IM) were performed to investigate thermodynamics parameters and the structural changes induced by the ligand binding, respectively. To estimate the binding affinity of drug molecule to subdomains IB and IIA in HSA protein, binding free energies were calculated using the Molecular Mechanics Poisson-Boltzmann Surface Area (MM-PBSA). The binding association constant (Ka) and the standard Gibbs free energy changes (G) of indometacin binding to the protein obtained from ITC technique are 9.12 103 M-1 and -5422 Kcal mol-1, respectively. All results indicate that the binding affinity of the drug molecule to subdomain IIA is more than that of subdomain IB of HSA. Thus the obtained thermodynamics characteristics, hydrophobic forces most likely played a major role, but hydrogen bonding also could not be ignored. One of the most important finding is that the subdomain IIA of HSA is the main binding site for indomethacin that confirmed by molecular dynamics simulation.
    Keywords: Human serum albumin (HSA), Isothermal titration calorimetry (ITC), Molecular dynamics simulation (MD), Indomethacin (IM), Molecular mechanics poisson, boltzmann surface area (MM, PBSA)
  • Sharareh Sajjadi, Hedayatollah Ghourchian*, Parvaneh Rahimi Pages 31-40
    Choline oxidase (ChOx) was chosen as a model enzyme for evaluating the performance of CNTs’ functional groups for development of enzyme electrodes. CNTs were functionalized with carboxylic acid, amine or amide groups. Carboxylic acid, amine and amide functionalized CNTs were obtained by acid treatment, ethylenediamine or tetraethylenepentamine chemically modification and ammonia plasma treatment, respectively. The CNTs with different functional groups were mixed with 1-butyl-3-methylimidazolium tetrafluoroborate as a typical room temperature ionic liquid. ChOx was adsorbed on the thus prepared nanocomposites containing different modified electrodes and its electron transfer and electroanalytical response towards choline was investigated. The resulting data showed that the ammonia plasma treated nanocomposite had higher apparent heterogeneous electron transfer rate constant (2.74 s-1) than the others, indicating more facile and rapid rates of electron transfer; while, nanocomposites modified with tetraethylenepentamine functionalized CNTs showed the most sensitive response towards choline (1.09×103 A M-1 m-2) with the lowest detection limit of 5.81×10-6 M. Consequently, tetraethylenepentamine modified electrodes were more convenient for choline biosensing applications.
    Keywords: Carbon nanotubes, Functionalization, Ionic liquid, Choline oxidase
  • Tayebeh Nazari, Mahdi Alijanianzadeh*, Ahmad Molaeirad, Maryam Khayati Pages 41-46
    Proteases are important enzymes that their role in various industries is undeniable. However, keeping enzymes stable during its activity in harsh conditions is so important. In this study, protease enzyme was immobilized on the porous silica particles and its stability in different temperatures and pHs was evaluated. First silica particles were aminated by 3-aminopropyltriethoxysilane then the protease enzyme was immobilized on the modified silica by glutaraldehyde cross-linking method and the immobilized enzyme’s activity was maintained for more than 40 days. Measuring the free subtilisin carlsberg enzyme activity and immobilized enzyme was performed according to the Lowry method. In another part, the effects of different pHs and temperatures on free and immobilized protease were evaluated. The immobilized protease activity was measured in temperature range between 25-75◦C and pH range 6.5-12. The absorption was read in 660nm. It is shown that the optimum temperature for immobilizaed enzyme is 50°C. The results showed that immobilized protease is more stable than free protease.
    Keywords: Alkaline serine protease, Subtilisin, Silica gel, Immobilization, Cross, linking
  • Abdollah Ramzanighara*, Fereshteh Ezzatighadi, Taghi Ghanbari Pages 47-52
    The number of patients with end-stage renal disease is growing rapidly in Asia. Patients with end stage renal disease failure (ESRD) undergoing long term hemodialysis (HD) are at risk for high oxidative stress. There is paucity of information with regard to oxidative stress during HD. Therefore, the aim of the present study was to evaluate catalase enzyme activity in erythrocytes and the total antioxidant capacity (TAC) in plasma before, during and after dialysis in hemodialysis patients. The cross-sectional study carried out in thirty four patients (16 males and 18 females) having mean age of 55 ± 16 years undergoing HD three times per week were included. The enzyme activity of catalase was measured by UV Spectrophotometric method and total antioxidant capacity in plasma were observed by ferric reducing ability of plasma (FRAP) assay method. All tests were performed before, during and after the process of dialysis. The prevalence of erythrocyte catalase enzyme activity was observed to be significantly decreased (P
    Keywords: Catalase, Total antioxidant, Hemodialysis, Oxidative stress