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author:("saudi, S")
1.  The Effects of Plasma Treated Electrospun Nanofibrous Poly (ε-caprolactone) Scaffolds with Different Orientations on Mouse Embryonic Stem Cell Proliferation  
Cell Journal (Yakhteh)  2014;16(3):245-254.
Assessments of cell reactions such as motility, orientation and activation to the topography of the substratum will assist with the fabrication of a proper implantable scaffold for future tissue engineering applications.The current challenge is to analyze the orientation effect of elecrospun nanofibers of poly (ε-caprolactone) (PCL) on viability and proliferation of mouse embryonic stem cells (mESCs).
Materials and Methods
In this experimental study, we used the electrospinning method to fabricate nanofibrous PCL scaffolds. Chemical and mechanical characterizations were specified by the contact angle and tensile test. O2plasma treatment was used to improve surface hydrophilicity. We used the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay to evaluate mESCs adhesion and proliferation before and after surface modification. The influence of the orientation of the nanofibers on mESCs growth was evaluated by scanning electron microscopy (SEM). Statistical analysis was performed using one-way analysis of variance (ANOVA) With differences considered statistically significant at p≤0.05.
The results showed that plasma treatment improved the hydrophilic property of PCL scaffolds. MTT assay showed a significant increase in proliferation of mESCs on plasma treated PCL (p-PCL) scaffolds compared to non-treated PCL (p=0.05). However gelatin coated tissue culture plate (TCP) had a better effect in initial cell attachment after one day of cell seeding. There was more cell proliferation on day 3 in aligned plasma treated (AP) nanofibers compared to the TCP. SEM showed optical density of the cell colonies. Aligned nanofibrous scaffolds had larger colony sizes and spread more than random nanofibrous scaffolds.
This study showed that plasma treating of scaffolds was a more suitable substrate for growth and cell attachment. In addition, aligned nanofibrous scaffolds highly supported the proliferation and spreading of mESCs when compared to random nanofibrous scaffolds and TCP.
PMCID: PMC4204185  PMID: 24611137
Embryonic Stem Cells; Nanofibers; Poly (ε-caprolactone); Surface Modification; Cell Proliferation
2.  Bacteriologic Profile of Pericardial Infections After Cardiac Surgery: Study in an Iranian Cardiovascular Tertiary Care Center 
Bacterial pericarditis is an important cause of post-surgery mortality and morbidity. This can be a preventable complication and the involved pathogens vary according to the time and location.
The aim of this study was to investigate the bacteriologic profile in patients with pericardial infections after cardiac surgery in the largest tertiary care center for cardiovascular diseases in Iran. The results can be applied for prevention, diagnosis, and treatment of similar patients in Iran.
Patients and Methods:
This prospective study was performed in Rajaie Cardiovascular Medical and Research Center (RCMRC), the largest tertiary care center for cardiovascular disease in Iran from March 2011 to March 2012. Patients who had undergone cardiac surgery with cardiopulmonary bypass and showed suggestive sign and symptoms of pericardial infections were registered and samples from their pericardial fluids were obtained to perform standard bacteriologic and antibiogram tests.
A total of 158 patients were registered. Bacteriologic findings were positive in 30 patients (19%). Staphylococcus epidermidis was the most frequent isolated organism, which was found in 22 patients (73.3%) with eight of them being methicillin-resistant strains.
The bacteriologic profile in our patient is specific to our own community. Knowledge about this profile can help us to improve prevention, diagnosis, and treatment of the affected patients.
PMCID: PMC4253795  PMID: 25478545
Microbial Sensitivity Test; Methicillin-Resistant Staphylococcus Aureus; Drug Resistance, Microbial; Pericardial Effusion; Cardiac Surgical Procedures; Adverse Effects
3.  Unsaturated Fatty Acid, cis-2-Decenoic Acid, in Combination with Disinfectants or Antibiotics Removes Pre-Established Biofilms Formed by Food-Related Bacteria 
PLoS ONE  2014;9(7):e101677.
Biofilm formation by food-related bacteria and food-related pathogenesis are significant problems in the food industry. Even though much disinfection and mechanical procedure exist for removal of biofilms, they may fail to eliminate pre-established biofilms. cis-2 decenoic acid (CDA), an unsaturated fatty acid messenger produced by Pseudomonas aeruginosa, is reportedly capable of inducing the dispersion of established biofilms by multiple types of microorganisms. However, whether CDA has potential to boost the actions of certain antimicrobials is unknown. Here, the activity of CDA as an inducer of pre-established biofilms dispersal, formed by four main food pathogens; Staphylococcus aureus, Bacillus cereus, Salmonella enterica and E. coli, was measured using both semi-batch and continuous cultures bioassays. To assess the ability of CDA combined biocides treatments to remove pre-established biofilms formed on stainless steel discs, CFU counts were performed for both treated and untreated cultures. Eradication of the biofilms by CDA combined antibiotics was evaluated using crystal violet staining. The effect of CDA combined treatments (antibiotics and disinfectants) on biofilm surface area and bacteria viability was evaluated using fluorescence microscopy, digital image analysis and LIVE/DEAD staining. MICs were also determined to assess the probable inhibitory effects of CDA combined treatments on the growth of tested microorganisms' planktonic cells. Treatment of pre-established biofilms with only 310 nM CDA resulted in at least two-fold increase in the number of planktonic cells in all cultures. While antibiotics or disinfectants alone exerted a trivial effect on CFU counts and percentage of surface area covered by the biofilms, combinational treatments with both 310 nM CDA and antibiotics or disinfectants led to approximate 80% reduction in biofilm biomass. These data suggests that combined treatments with CDA would pave the way toward developing new strategies to control biofilms with widespread applications in industry as well as medicine.
PMCID: PMC4084997  PMID: 25000301
4.  Biochemical and Neurotransmitters Changes Associated with Tramadol in Streptozotocin-Induced Diabetes in Rats 
BioMed Research International  2014;2014:238780.
The incidence of diabetes is increasing worldwide. Chronic neuropathic pain occurs in approximately 25% of diabetic patients. Tramadol, an atypical analgesic with a unique dual mechanism of action, is used in the management of painful diabetic neuropathy. It acts on monoamine transporters to inhibit the reuptake of norepinephrine (NE), serotonin (5-HT), and dopamine (DA). The purpose of this study was to evaluate the effects of diabetes on the brain neurotransmitter alterations induced by tramadol in rats, and to study the hepatic and renal toxicities of the drug. Eighty Sprague-Dawley rats were divided randomly into two sets: the normal set and the diabetic set. Diabetes was induced in rats. Tramadol was administered orally once daily for 28 days. The levels of DA, NE, and 5-HT in cerebral cortex, thalamus/hypothalamus, midbrain, and brainstem were evaluated in rats. In addition, the renal toxicity and histopathological effects of the drug were assessed. The induction of diabetes altered neurotransmitter levels. Oral administration of tramadol significantly decreased the neurotransmitter levels. Diabetes significantly altered the effects of tramadol in all brain regions. Tramadol affected function and histology of the liver and kidney. The clinical effects of tramadol in diabetic patients should be stressed.
PMCID: PMC4058222  PMID: 24971322
5.  Partial Optimization of Endo-1, 4-Β-Xylanase Production by Aureobasidium pullulans Using Agro-Industrial Residues 
Objective(s) : Although bacteria and molds are the pioneering microorganisms for production of many enzymes, yet yeasts provide safe and reliable sources of enzymes with applications in food and feed.
Materials and Methods: Single xylanase producer yeast was isolated from plant residues based on formation of transparent halo zones on xylan agar plates. The isolate showed much greater endo-1, 4-β-xylanase activity of 2.73 IU/ml after optimization of the initial extrinsic conditions. It was shown that the strain was also able to produce β-xylosidase (0.179 IU/ml) and α-arabinofuranosidase (0.063 IU/ml). Identification of the isolate was carried out and the endo-1, 4-β-xylanaseproduction by feeding the yeast cells on agro-industrial residues was optimized using one factor at a time approach.
Results: The enzyme producer strain was identified as Aureobasidiumpullulans. Based on the optimization approach, an incubation time of 48 hr at 27°C, inoculum size of 2% (v/v), initial pH value of 4 and agitation rate of 90 rpm were found to be the optimal conditions for achieving maximum yield of the enzyme. Xylan, containing agricultural residues, was evaluated as low-cost alternative carbon source for production of xylanolytic enzymes. The production of xylanase enzyme in media containing wheat bran as the sole carbon source was very similar to that of the medium containing pure beechwoodxylan.
Conclusion:This finding indicates the feasibility of growing of A. pullulans strain SN090 on wheat bran as an alternate economical substrate in order for reducing the costs of enzyme production and using this fortified agro-industrial byproduct in formulation of animal feed.
PMCID: PMC3933801  PMID: 24570830
Aureobasidiumpullulans; Endo-1; 4-β-xylanase; Extracellular enzyme; Optimization
6.  Evaluation of the Relationship between the Incubation Time and Carotenoid Production in Rhodotorula Slooffiae and R. Mucilaginosa Isolated from Leather Tanning Wastewater  
Objective(s): Carotenoids which are naturally synthesized by fungi such as yeasts can act as an antioxidant which is closely related to their ability to decrease the risk of a variety of degenerative diseases. In recent years, the increase of demand for carotenoids obtained from natural sources has promoted major efforts to improve carotenoid production from biological sources such as pigmented yeasts. The aim of this study was comparing incubation time and carotenoid production in Rhodotorula slooffiae and R. mucilaginosa isolated from leather tanning wastewater.
Materials and Methods: To isolate the carotenoid pigment, cells were suspended in acetone and broken using a homogenizer, followed by centrifugation and separation of supernatant. In order to study the effect of incubation time, samples were held at 30 ˚С in a shaker at 150 rpm for 24, 48, 72, 96, and 120 hr. For analytical evaluation, pigments were measured spectrophotometrically at 450 nm using the extinction coefficient E1%450=2500.
Results: The results showed that the content of total carotenoid in R. slooffiae was the highest when samples were incubated for 72 hr. Overall, R. mucilaginosa had more potential to produce carotenoid. The best incubation periods for R. slooffiae and R. mucilaginosa were 72 hr and 48 hr, respectively.
Conclusion: It seemed that the maximum rate of total carotenoid was not directly associated with the maximum amount of cell biomass and the type of carotenoid and their relative amount may vary depending on genus of yeast.
PMCID: PMC3874099  PMID: 24379970
Antioxidant; Carotenoid; Incubation time; Rhodotorula Spectrophotometry
7.  Incidence of Catheter-Related Infections in Hospitalized Cardiovascular Patients 
Catheter Related Blood stream Infections (CRBSI) are prevalent and a potentially fatal complication pertaining to cardiovascular implant devices. There have been no major studies on bacterial colonization of catheters in cardiovascular patients in Iran.
To evaluate the incidence of catheter colonization of bacteria in the largest Iranian cardiovascular center.
Patients and Methods:
March 2011 to 2012, Cauterization procedures performed on 60 patients hospitalized in Rajaie Cardiovascular Medical and Research Center, Tehran, Iran, with arterial or venous catheterization, inserted 48 hours or more, catheter evaluations done by culture methods. Blood cultures were also obtained simultaneously.
Forty-four out of 60 catheters (73.3%) were positive with a significant colony count. Of 44 positive cases, 11 patients had positive blood culture. Three most frequently isolated microorganisms were Staph Albus [14 (32%)], Entrococcu [12 (27%)] and Acinetobacter [5 (11%)]. gram-positive cocci were sensitive to Vancomycin and Linezolid and gram-negative bacilli were sensitive to Amikacin, Gentamicin, Tobramycin and Imipenem.
The study findings revealed that the catheter infection in our patients had sources other than normal skin flora. These results will assist in determining the possible source of the infections, furthermore, how they are transmitted, moreover aid in controlling and preventing these dangerous in- infections.
PMCID: PMC4253759  PMID: 25478502
Catheter-Related Infections; Cardiovascular Diseases; Bacteremia; Hospitalization; Iran
8.  Comparative Study of The Effect of LPS on The Function of BALB/c and C57BL/6 Peritoneal Macrophages 
Cell Journal (Yakhteh)  2013;15(1):45-54.
Macrophages influence their environment and surrounding immune cells as soon as stimulators affect them. Different sources of macrophages induce different reactions in their neighboring immune cells,which result in non-uniform immunologic outcomes. In this experimental research, we compare the behavior of peritoneal macrophages to lipopolysaccharide (LPS) stimulation from BALB/cmice as an indicator of a type 2 immune response and from C57BL/6 mice as an indicator of a type 1 immune response.
Materials and Methods:
In this experimental study, peritoneal macrophages prepared from thioglycolate stimulated BALB/c and C57BL/6 micewere treated with 1µg/ml LPS. At different time points after LPS treatment, nitric oxide (NO), interferon gamma (IFN-λ), interleukin 4 (IL-4),transforming growth factor β1(TGF-β1), interleukin 17 (IL-17), and interleukin 10(IL-10) production were measured in the supernatants of all macrophage cultures. Indoleamine 2, 3 dioxygenase (IDO) and phagocytic activitywere analyzed in the different experimental groups. The supernatant effects of LPS-treated macrophages on splenocyte proliferation was assessed by the colorimetric method using a 3-(4,5-Dimethylthiazol- 2-yl)-2, 5-diphenyltetrazolium bromide (MTT) reagent.
According to cytokine analysis, different mouse strains show different cytokine patterns in response to LPS. C57BL/6 macrophages produced more IL-17, IL-10, and IFN-λ, while BALB/c macrophages produced more TGF-β1 and IL-4. There was no significant difference in IDO activity between strains (p≤0.05). BALB/c mice produced more NO inthe first 24 hours after LPS treatment,but C57BL/6 produced more NO at 72 hours post-LPS treatment. Macrophages from both strains hada suppressor effect on splenocyte proliferation, but this effect was stronger in BALB/c mice.
The results show that macrophages from different genetic backgrounds respond differently to the same stimulus in aspects of type, intensity, and time of response. The consideration of these aspects will enableresearchers to use correct treatment programs for immune-regulation or immunotherapy.
PMCID: PMC3660024  PMID: 23700560
Macrophage; Thioglycolate; LPS; BALB/c; C57BL/6
9.  Prediction of oocyte developmental competence in ovine using glucose-6-phosphate dehydrogenase (G6PDH) activity determined at retrieval time 
To determine whether G6PDH-activity measured by Brilliant Cresyl Blue known as BCB dye, predicts developmental competence within cohorts of ovine oocytes.
Ovine oocytes were exposed to BCB staining and categorized into two groups: BCB+ (blue cytoplasm, low G6PDH-activity) and BCB- (colorless cytoplasm, high G6PDH-activity). After maturation in vitro, oocytes were subjected to fertilization followed by in vitro embryo culture.
We observed a significant difference in oocyte diameter considering BCB+ and BCB- oocytes. BCB+ and Control groups showed significantly higher maturation rates compared to BCB- group. There were significantly more cleaved embryos in BCB+ and control groups than in BCB- group. Blastocyst rate was significantly higher for BCB+ group compared to control and BCB- groups with control group being significantly higher than BCB- group.
G6PDH-activity is a strong predictive marker of oocyte competence and may be useful in identifying oocytes with a good prognosis for further develop.
PMCID: PMC3270133  PMID: 21870182
Ovine; Oocyte; Glucose-6-phosphate dehydrogenase; BCB; Developmental competence
10.  Degradation of a textile reactive azo dye by a combined biological-photocatalytic process: Candida tropicalis Jks2 -Tio2/Uv 
In the present study, the decolorization and degradation of Reactive Black 5 (RB5) azo dye was investigated by biological, photocatalytic (UV/TiO2) and combined processes. Application of Candida tropicalis JKS2 in treatment of the synthetic medium containing RB5 indicated complete decolorization of the dye with 200 mg/L in less than 24 h. Degradation of the aromatic rings, resulting from the destruction of the dye, did not occur during the biological treatment. Mineralization of 50 mg/L RB5 solution was obtained after 80 min by photocatalytic process (in presence of 0.2 g/L TiO2). COD (chemical oxygen demand) was not detectable after complete decolorization of 50 mg/L RB5 solution. However, photocatalytic process was not effective in the removal of the dye at high concentrations (≥200 mg/L). With 200 mg/L concentration, 74.9% of decolorization was achieved after 4 h illumination under photocatalytic process and the absorbance peak in UV region (attributed to aromatic rings) was not completely removed. A two-step treatment process, namely, biological treatment by yeast followed by photocatalytic degradation, was also assessed. In the combined process (with 200 mg/L RB5), absorbance peak in UV region significantly disappeared after 2 h illumination and about 60% COD removal was achieved in the biological step. It is suggested that the combined process is more effective than the biological and photocatalytic treatments in the remediation of aromatic rings.
PMCID: PMC3570398  PMID: 23369285
Azo dyes; Candida tropicalis; Combined wastewater treatment
12.  Cloning and Expression of Leishmania infantum LPG3 Gene by the Lizard Leishmania Expression System 
Various prokaryotic and eukaryotic expression systems have been developed for the production of recombinant proteins. In the present study, we used a new protein expression system based on the Iranian Lizard Leishmania, a trypanosomatid protozoan as a host, for the expression of LPG3 gene from Leishmania infantum (L.infantum).
The LPG3 gene was cloned in the expression cassette for integration into the small subunit of the ribosomal RNA locus of Lizard Leishmania genome by electroporation. Expression of the recombinant LPG3 protein was confirmed by western blotting and immunofluorescence staining.
Western blotting confirmed the expression and production of rLPG3 protein. Immunofluoresence analysis also revealed the staining throughout the cytoplasm of transfected parasites, indicating that the protein has been expressed.
These results demonstrate that Leishmania cells can be suggested an expression system for the production of recombinant LPG3 (rLPG3) to further research in vaccine designing against leishmaniasis.
PMCID: PMC3558223  PMID: 23407850
Leishmania infantum; Leishmania; Recombinant proteins; Vaccines
13.  Minimal phenotypic test for simple differentiation of Xanthomonas campestris from other yellow-pigmented bacteria isolated from soil 
Background and Objectives
Isolation of Xanthomonas campestris from soil has a wide range of applications from monitoring of phytopathogenic populations in soil to screening of improved xanthan-producing strains. Identification of Xanthomonas campestris and its pathovars requires pathogenicity tests in addition to phenotypic and molecular characterization.
Materials and Methods
Thirty phenotypic tests were carried out on 57 yellow-pigmented bacterial isolates obtained from soil of cabbage farms after screening on Selective Xanthomonas (SX) agar and transferring on Yeast Malt agar. Absorption spectra of pigments and capability of biopolymer production were determined for the isolates. Some characteristics of the biopolymer produced and presence of a X. campestris-specific gene marker were investigated for nine putative X. campestris isolates.
The present study introduces a set of simple phenotypic tests including urease, acid production from sucrose, mucoid growth on 5% sucrose, starch hydrolysis, growth in 4% NaCl, motility and utilization of asparagine as sole carbon and nitrogen source for quick and inexpensive tentative identification of Xanthomonas campestris. Validation of these tests was confirmed in 100% of the cases by characterization of bacterial exopolysaccharide as xanthan and production of genus-specific xanthomonadin pigment. Moreover, tracking of hrc gene among putative X. campestris isolates gave positive results in 80% of cases.
The Minimal simple phenotypic tests facilitate the screening and differentiation of putative X. campestris isolates from other false bacterial strains isolated from soil on semiselective SX agar.
PMCID: PMC3279810  PMID: 22347588
biochemical tests; soil; xanthan; Xanthomonas campestris; yellow-pigmented bacteria
14.  N-terminally fusion of Her2/neu to HSP70 decreases efficiency of Her2/neu DNA vaccine 
Cell Stress & Chaperones  2010;15(5):631-638.
DNA vaccines consisted of tumor-associated antigen (TAA) are well suited for immunotherapy against tumor. The construct can contain TAA fused to an appropriate molecule (biologic adjuvant) to improve the efficacy of anti-tumor immune response. Heat shock protein 70 (HSP70) has been shown to be an excellent candidate, capable of cross-priming TAA by antigen presenting cells leading to a robust T-cell response. However, the relationship between strong T-cell responses and tumor rejection is not always mutually exclusive, for which TAA loss or activation of suppressive mechanisms may occur. HSP70 fused to downstream of Her2/neu as DNA vaccine has been shown to be efficient against Her2-expressing tumors. In this study, we examined if N-terminally fusion of Her2/neu to HSP70 could also improve efficiency of Her2/neu DNA vaccine. Therefore, mice with an established Her2/neu expressing tumor were immunized with DNA vaccine consisting of extracellular and trans-membrane domain (EC+TM) of rat Her2/neu alone or N-terminally fused to HSP70 and immune response was evaluated. Administration of rat Her2/neu led to partial control of tumor progression. Surprisingly, fusion of HSP70 to N-terminal of rat Her2/neu led to tumor progression. Our result proposes that fusion direction of biologic adjuvant is an important consideration when Her2/neu is used.
PMCID: PMC3006617  PMID: 20224916
HSP70; Her2; Biologic adjuvant; Regulatory T cells
15.  Molecular Evolution, Structure, and Function of Peroxidasins 
Chemistry & Biodiversity  2012;9(9):1776-1793.
Peroxidasins represent the subfamily 2 of the peroxidase-cyclooxygenase superfamily and are closely related to chordata peroxidases (subfamily 1) and peroxinectins (subfamily 3). They are multidomain proteins containing a heme peroxidase domain with high homology to human lactoperoxidase that mediates one- and two-electron oxidation reactions. Additional domains of the secreted and glycosylated metalloproteins are type C-like immunoglobulin domains, typical leucine-rich repeats, as well as a von Willebrand factor C module. These are typical motifs of extracellular proteins that mediate protein–protein interactions. We have reconstructed the phylogeny of this new family of oxidoreductases and show the presence of four invertebrate clades as well as one vertebrate clade that includes also two different human representatives. The variability of domain assembly in the various clades was analyzed, as was the occurrence of relevant catalytic residues in the peroxidase domain based on the knowledge of catalysis of the mammalian homologues. Finally, the few reports on expression, localization, enzymatic activity, and physiological roles in the model organisms Drosophila melanogaster, Caenorhabditis elegans, and Homo sapiens are critically reviewed. Roles attributed to peroxidasins include antimicrobial defense, extracellular matrix formation, and consolidation at various developmental stages. Many research questions need to be solved in future, including detailed biochemical/physical studies and elucidation of the three dimensional structure of a model peroxidasin as well as the relation and interplay of the domains and the in vivo functions in various organisms including man.
PMCID: PMC3533774  PMID: 22976969
Peroxidasin; Peroxidase; Immunoglobulin domain; Leucin-rich repeat domain; von Willebrand factor C

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