فهرست مطالب

Iranian Biomedical Journal - Volume:21 Issue: 4, Jul 2017

Iranian Biomedical Journal
Volume:21 Issue: 4, Jul 2017

  • تاریخ انتشار: 1396/03/17
  • تعداد عناوین: 10
|
  • Mohammad Hossein Asghari, Milad Moloudizargari, Mohammad Abdollahi Pages 203-204
  • Najmeh Zarei, Vahid Khalaj Page 205
  • Shahriyar Abdoli, Farzin Roohvand, Ladan Teimoori-Toolabi, Mohammad Ali Shokrgozar, Mina Bahrololoumi, Kayhan Azadmanesh Pages 206-217
    Background
    Oncolytic herpes simplex virus (oHSV)-based vectors lacking γ34.5 gene, are considered as ideal templates to construct efficient vectors for (targeted) cancer gene therapy. Herein, we reported the construction of three single/dually-flourescence labeled and γ34.5-deleted, recombinant HSV-1 vectors for rapid generation and easy selection/isolation of different HSV-Based vectors.
    Methods
    Generation of recombinant viruses was performed with conventional homologous recombination methods using green fluorescent protein (GFP) and BleCherry harboring shuttle vectors. Viruses were isolated by direct fluorescence observation and standard plaque purifying methods and confirmed by PCR and sequencing and flow cytometry. XTT and plaque assay titration were performed on Vero, U87MG, and T98 GBM cell lines.
    Results
    We generated three recombinant viruses, HSV-GFP, HSV-GR (Green-Red), and HSV-Red. The HSV-GFP showed two log higher titer (1010 PFU) than wild type (108 PFU). In contrast, HSV-GR and HSV-Red showed one log lower titer (107 PFU) than parental HSV. Cytotoxicity analysis showed that HSV-GR and HSV-Red can lyse target tumor cells at multiplicity of infection of 10 and 1 (P
    Conclusion
    Our oHSVs provide a simple and an efficient platform for construction and rapid isolation of 2nd and 3rd generation oHSVs by replacing the inserted dyes with transgenes and also for rapid identification via fluorescence activated cell sorting. These vectors can also be used for tracing the efficacy of therapeutic agents on target cells, imaging of neural or tumoral cells in vitro/in vivo and as oncolytic agents in cancer therapy.
    Keywords: Oncolytic viruses, Herpes simplex virus, Homologous recombination, Flow cytometry, Fluorescence microscopy
  • Jamal Mohammadi Ayenehdeh, Bahareh Niknam, Seyed Mahmoud Hashemi, Hossein Rahavi, Nima Rezaei, Masoud Soleimani, Nader Tajik Pages 218-227
    Background
    Islet transplantation could be an ideal alternative treatment to insulin therapy for type 1 diabetes Mellitus (T1DM). This clinical and experimental field requires a model that covers problems such as requiring a large number of functional and viable islets, the optimal transplantation site, and the prevention of islet dispersion. Hence, the methods of choice for isolation of functional islets and transplantation are crucial.
    Methods
    The present study has introduced an experimental model that overcomes some critical issues in islet transplantation, including in situ pancreas perfusion by digestive enzymes through common bile duct. In comparison with conventional methods, we inflated the pancreas in Petri dishes with only 1 ml collagenase type XI solution, which was followed by hand-picking isolation or Ficoll gradient separation to purify the islets. Then we used a hydrogel composite in which the islets were embedded and transplanted into the peritoneal cavity of the streptozotocin-induced diabetic C57BL/6.
    Results
    As compared to the yield of the classical methods, in our modified technique, the mean yield of isolation was about 130-200 viable islets/mouse pancreas. In vitro glucose-mediated insulin secretion assay indicated an appropriate response in isolated islets. In addition, data from in vivo experiments revealed that the allograft remarkably maintained blood glucose levels under 400 mg/dl and hydrogel composite prevents the passage of immune cells.
    Conclusion
    In the model presented here, the rapid islet isolation technique and the application of biomimetic hydrogel wrapping of islets could facilitate islet transplantation procedures.
    Keywords: Islet pancreas_isolation_transplantation_Type 1 diabetes mellitus
  • Zeinab Nematollahi, Mohammad Tafazzoli-Shadpour, Ali Zamanian, Amir Seyedsalehi, Mohammad-Behgam Shadmehr, Fariba Ghorbani, Fereshte Mirahmadi Pages 228-239
    Background
    Since the treatments of long tracheal lesions are associated with some limitations, tissue engineered trachea is considered as an alternative option. This study aimed at preparing a composite scaffold, based on natural and synthetic materials for tracheal tissue engineering.
    Methods
    Nine chitosan silk-based scaffolds were fabricated using three freezing rates (0.5, 1, and 2°C/min) and glutaraldehyde (GA) concentrations (0, 0.4, and 0.8 wt%). Samples were characterized, and scaffolds having mechanical properties compatible with those of human trachea and proper biodegradability were selected for chondrocyte cell seeding and subsequent biological assessments.
    Results
    The pore sizes were highly influenced by the freezing rate and varied from 135.3×372.1 to 37.8×83.4 µm. Swelling and biodegradability behaviors were more affected by GA rather than freezing rate. Tensile strength raised from 120 kPa to 350 kPa by an increment of freezing rate and GA concentration. In addition, marked stiffening was demonstrated by increasing elastic modulus from 1.5 MPa to 12.2 MPa. Samples having 1 and 2°C/min of freezing rate and 0.8 wt% GA concentration made a non-toxic, porous structure with tensile strength and elastic modulus in the range of human trachea, facilitating the chondrocyte proliferation. The results of 21-day cell culture indicated that glycosaminoglycans content was significantly higher for the rate of 2°C/min (12.04 µg/min) rather than the other (9.6 µg/min).
    Conclusion
    A homogenous porous structure was created by freeze drying. This allows the fabrication of a chitosan silk scaffold cross-linked by GA for cartilage tissue regeneration with application in tracheal regeneration.
    Keywords: Chitosan, Trachea, Therapeutic Substitution, Regeneration, Tissue Scaffold
  • Abbas Shali, Garshasb Rigi, Majid Pornour, Gholamreza Ahmadian Pages 240-248
    Background
    Improved cyan fluorescent protein (ICFP) is a monochromic, green fluorescent protein (GFP) derivative produced by Aequorea macrodactyla in a process similar to GFP. This protein has strong absorption spectra at wavelengths 426-446 nm. ICFP can be used in cell, organelle or intracellular protein labeling, investigating the protein-protein interactions as well as assessing the promoter activities.
    Methods
    In our previous study, the promoters of two chitinases (ChiS and ChiL) from Bacillus pumilus SG2 were assessed in B. subtilis and their regulatory elements were characterized. In the present study, icfp was cloned downstream of several truncated promoters obtained in the former study, and ICFP expression was evaluated in B. subtilis.
    Results
    Extracellular expression and secretion of ICFP were analyzed under the control of different truncated versions of ChiSL promoters grown on different media. Results from SDS-PAGE and fluorimetric analyses showed that there were different expression rates of CFP; however, the UPChi-ICFP3 construct exhibited a higher level of expression and secretion in the culture medium.
    Conclusion
    Our presented results revealed that inserting this truncated form of Chi promoter upstream of the ICFP, as a reporter gene, in B. subtilis led to an approximately ten fold increase in ICFP expression.
    Keywords: Cyan fluorescent protein, Medical reporter gene, Medical screenable marker, Medicinal Protein Engineering
  • Maurice George Ekpenyong, Sylvester Peter Antai, Atim David Asitok, Bassey Offiong Ekpo Pages 249-260
    Background
    A glycolipopeptide biosurfactant produced by Pseudomonas aeruginosa strain IKW1 reduced the surface tension of fermentation broth from 71.31 to 24.62 dynes/cm at a critical micelle concentration of 20.80 mg/L. The compound proved suitable for applications in emulsion stabilization in food, as well as in cosmetic and pharmaceutical formulations.
    Methods
    In the present study, Plackett-Burman design (PBD) and response surface method (RSM) were employed to screen and optimize concentrations of trace nutrients in the fermentation medium, to increase surfactant yield.
    Results
    The PBD selected 5 out of the 12 screened significant trace nutrients. The RSM, on the other hand, resulted in the production of 84.44 g glycolipopeptide/L in the optimized medium containing 1.25 mg/L nickel, 0.125 mg/L zinc, 0.075 mg/L iron, 0.0104 mg/L boron, and 0.025 mg/L copper.
    Conclusion
    Significant second-order quadratic models for biomass (P
    Keywords: Pseudomonas aeruginosa, Surface-active agents, Fermentation, Nickel, Copper
  • Jai Prakash, Balraj Mittal, Apurva Srivastava, Shally Awasthi, Pranjal Srivastava, Neena Srivastava Pages 261-269
    Background
    Obesity is a very common disorder resulting from an imbalance between food intake and energy expenditure, and it has a substantial impact on the development of chronic diseases. The aim of this study was to examine the association of INSIG2 (rs7566605) gene polymorphism with obesity and obesity associated phenotypes in North Indian subjects.
    Methods
    The variants were investigated for association in 642 obese and non-obese individuals. The genotyping of INSIG2 (rs7566605) single nucleotide polymorphism was analyzed by the TaqMan allelic discrimination protocol.
    Results
    A significant association was observed for INSIG2 (rs7566605) single nucleotide polymorphism with obesity and obesity-related phenotypes. Furthermore, a significant relationship was found between the rs7566605 and insulin, homeostasis model of assessment-insulin resistance, the percentage of body fat, fat mass, leptin, and adiponectin.
    Conclusion
    The present study observed significant association between INSIG2 (rs7566605) single nucleotide polymorphism and obesity, as well as obesity-associated phenotypes in North Indian population.
    Keywords: INSIG2, Body mass index, Insulin, Insulin resistance, Polymorphism
  • Meghdad Abdollahpour-Alitappeh, Majid Lotfinia, Sepand Razavi-Vakhshourpour, Saeed Jahandideh, Hamid Najminejad, Koushan Sineh Sepehr, Reza Moazami, Elnaz Shams, Mahdi Habibi-Anbouhi, Mohsen Abolhassani Pages 270-274
    Background
    Reduction/alkylation is one of the leading strategies for the development of antibody drug conjugates (ADCs). Precise control of the reduction process would not only yield a defined number of free thiols per antibody but also result in development of more homogenous conjugates.
    Methods
    In the present study, we investigated the effect of various dithiothreitol (DTT) concentrations, temperature conditions, and DTT exposure times on antibody reduction. After antibody reduction, the Ellman's test and SDS-PAGE analysis were used to evaluate free thiols produced and confirm the reduction process, respectively.
    Results
    DTT concentration seems to be a potential factor in the reduction process. Concentrations of 0.1, 1, 5, 10, 20, 50, and 100 mM DTT at 37°C for 30 minutes resulted in approximately 0.4, 1.2, 5.4, 7, 8, 8, and 8 thiols per antibody, respectively.
    Conclusion
    Optimized site-specific conjugation can provide better process control and reproducibility for the development of disulfide-based ADCs.
    Keywords: Conjugation, Dithiothreitol, Antibody drug conjugate
  • Ensieh Lotfali, Ali Ghajari, Parivash Kordbacheh, Farideh Zaini, Hossein Mirhendi, Rasoul Mohammadi, Fatemeh Noorbakhsh, Sassan Rezaie Pages 275-281
    Background
    Candida parapsilosis is one of the five common strains of yeasts involved in invasive candidiasis. The expression analysis of sterol biosynthesis pathway genes, which are associated with resistance, can assist the better understanding of antifungal resistance mechanisms.
    Methods
    The antifungal susceptibility of 120 clinical C. parapsilosis isolates was examined. The changes in the gene expression related to resistance were analyzed.
    Results
    Eight strains were resistant to fluconazole (FLC), itraconazole (ITC), and amphotericin B (AMB). The regulation variations included increased mRNA levels of ERG3, ERG6, and ERG11 and decreased mRNA levels of ERG3 and ERG6 in response to FLC. ERG11 mRNA level increases in response to ITC and AMB.
    Conclusion
    The mechanism of resistance to azoles in C. parapsilosis is very similar to C. Albicans. This feature may help to design new treatment strategy for candidiasis.
    Keywords: Candida parapsilosis, Gene expression, Ergosterol biosynthesis