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Showing 9 results for Gene Expression

Nasrollahi Omran, A, Nazemi, A, Kihanian, Sh, Aryana , N,
Volume 8, Issue 5 (1-2015)
Abstract

Abstract Background and Objective: With the development of drug resistance in strains of fungi, there is a considerable resistance of Candida albicans strains to fluconazole. Molecular studies are developing to determine the relationship of such a drug resistance with the increased gene expression of enzymes produced in drug-resistant Candida isolates. We aimed to evaluate the relationship between extracellular lipase gene (LIP8) expression of Candida albicans isolated from candidiasis and sensitivity or resistance to fluconazole. Material and Methods: Drug susceptibility of Candida albicans was performed in oral and vaginal candidiasis to determine the proportion of strains sensitive or resistant to fluconazole using NCCLS method. To evaluate and compare the expression of these genes in the susceptible and resistant strains, RT real-time PCR reaction was used. Results: Of 46 Candida albicans, 20 were susceptible, 12 were semi-susceptible and 14 were resistant to fluconazole. By using PCR reaction, the results showed that the expression of this gene in fluconazole-susceptible isolates was moderate, while it was high in the isolates resistant to fluconazole. Conclusion: The results of lipase gene (LIP8) expression showed that the additional expression of some genes of the enzymes responsible for virulence of Candida may also play a role in resistance to fluconazole. Keywords: Candidiasis, Lipase Gene Expression, RT real-time PCR, Fluconazole
Nahid Ariana, Ali Nazemi , Ayatollah Nasrollahi Omran,
Volume 9, Issue 4 (10-2015)
Abstract

Abstract

      Background and objectives: More Candida albicans strains are reported resistant to fluconazole in patients with AIDS, cancer and organ recipients. Fluconazole resistance can be attributed to changes in pathways of sterol biosynthesis, mutation in or overexpression of ERG11 and the expression of CDR1, CDR2, and MDR1. This study aimed to compare the expression of CDR1, CDR2, and MDR1 in C. albicans resistant and susceptible to fluconazole.

       Methods: MIC testing for fluconazole was performed on C. albicans isolates isolated from patients with oral and vaginal candidiasis to determine resistant and susceptible strains. Then real time PCR was performed on the resistant and susceptible isolates and the expression of CDR1, CDR2, and MDR1 was compared in C. albicans.

     Results: Of 46 Candida albicans isolates, 20 susceptible isolates, 12 semi-susceptible isolates and 14 resistant isolates were identified by MIC. After real time PCR was performed, Candida albicans isolates susceptible to fluconazole showed moderate expression of CDR1, CDR2, and MDR1 genes, while resistant isolates showed slight or no expression.

      Conclusion: Increased expression of CDR1, CDR2, and MDR1 had less and insignificant role in resistance to fluconazole.

      Keywords: Candida Albicans, Gene Expression, Real time PCR method


Hadi Koohsari , Ezzat Allah Ghaemi , Nour Amir Mozaffari , Abdolvahab Moradi ,
Volume 10, Issue 1 (3-2016)
Abstract

Abstract

      Background and Objective: Agr is the most important regulatory system for the expression of Staphylococcus aureus virulence factors in different conditions. Agr acts as a quorum sensing system in this bacterium which is activated by increased cell concentration during the transition from logarithmic growth phase to stationary phase. Its role is to upregulate the secretory virulence factors such as alpha-hemolysin and inhibit the transcription of surface proteins including protein A-encoding gene. The aim of this study was to assess the relationship between the agr system expression and some virulence factors of Staphylococcus aureus in Brain-heart infusion (BHI) culture medium.

     Methods: The expression level of agrA and RNAIII genes from the agr locus along with the expression of hla, spa and mecA genes in BHI broth were assessed in different growth phases using Real time-PCR. Also, gyrB was used as an internal control in this study.

     Results: The growth curve of the five tested isolates in BHI broth at 24 hours showed that all the isolates had relatively similar growth patterns. AgrA gene expression in the stationary phase was decreased by 0.89-fold compared with the logarithmic phase. Although the expression of RNAIII gene increased by 3-fold, hla expression decreased by 0.47-fold.

     Conclusion: An inactive agr system is observed in the BHI broth medium. BHI broth medium contains high amounts of suitable nutrients for the growth of Staphylococcus aureus, thus the bacteria do not require the activity of the agr system for the regulation of the virulence genes in these conditions.

    


Mohammad Arjmand , Ezatallah Ghaemi , Ailar Jamalli ,
Volume 11, Issue 1 (2-2017)
Abstract

ABSTRACT
        Background and Objectives: Biofilm is a population of bacteria growing on a surface and enclosed in an exopolysaccharides matrix, which increases resistance to antimicrobial agents and immune response. Uropathogenic Escherichia coli (UPEC) are biofilm-forming bacteria and the most common cause of urinary tract infections (UTIs). This study evaluated the effect of different concentrations of glucose, NaCl, blood, serum and urine on biofilm formation and antigen 43 (Ag43) gene expression, as a main gene involved in biofilm formation.
        Methods: Among E. coli isolates from patients with UTI, four extended-spectrum beta-lactamase (ESBL) and non-ESBL strains, and a standard UPEC strain were selected. Biofilm formation of the strains in brain heart infusion (BHI) broth with different concentrations of glucose, NaCl, sheep blood, serum and human urine was evaluated using microplate method and crystal violet staining. Ag43 gene expression was investigated using Real-Time polymerase chain reaction, SYBR Green dye, and specific primers.
           Results: Presence of glucose at all concentrations reduced biofilm formation. Presence of 1% NaCl, 1% sheep blood, 10% bovine serum, and 5% urine significantly increased biofilm formation. Expression of Ag43 by the strains grown under 1% glucose, 1% NaCl, 1% sheep blood, 10% bovine serum and 5% urine decreased.
         Conclusion: All environmental factors other than glucose may increase biofilm formation of E. coli at different concentrations. This is not affected by factors such as isolation from inpatient or outpatients and type of strains (ESBL or non-ESBL). Contrary to our expectations, Ag43 expression is independent of environmental factors and decreases even under the most suitable concentrations.
          Keywords: Biofilms, Uropathogenic Escherichia coli, UTI, Antigen 43, Real-Time PCR.

Mahshid Zandi , Mohammad Ebrahimifard, Abdolvahab Moradi,
Volume 11, Issue 3 (6-2017)
Abstract

ABSTRACT
       Background and Objective: MiRNAs are small RNAs that are expressed in most eukaryotes, and can regulate gene expression by attaching to the 3’ end of target mRNA. MicroRNA-101 (miR-101) post-transcriptional regulation is important for host-virus interactions. In addition, miR-101 has a tumor suppressive role in liver cancer and metastasis, and induces apoptosis in tumor cells. We examined miR-101 expression in patients with chronic hepatitis B, hepatitis B virus (HBV)-associated cirrhosis and healthy individuals.
       Methods: The study was performed on 108 whole blood samples (36 samples from each group) collected in EDTA tubes. RNA was extraction by RNX-plus kit according to the manufacturer’s protocol. Finally, miRNA expression was evaluated using relative real time PCR.
         Results: A 2.4-fold increase was observed in miR-101 expression in patients with chronic hepatitis B, while there was a 3.5-fold increase in miR-101 expression in patients with HBV-associated cirrhosis compared with healthy controls (P=0.003). MiR-101 overexpression in patients with HBV-associated cirrhosis was more notable that in patients with chronic hepatitis B.
         Conclusion: According to the results, evaluating miR-101 expression may predict disease progression from chronic hepatitis B to HBV-associated cirrhosis.
         Keywords: MicroRNAs, Chronic Hepatitis B, Liver Cirrhosis, MiR-101.

Kazem Maftuni , Peyman Zare ,
Volume 11, Issue 5 (9-2017)
Abstract

ABSTRACT
           Background and objective: Considering the toxic side effects of chemotherapy in treatment of cancer, anticancer drugs of natural origin including probiotic Lactobacillus strains have recently attracted a lot of attention.
Methods: After culturing chronic myeloid leukemia cell line K562 in 96-well plates, effects of different concentrations of culture supernatant from Lactobacillus casei on differentiation of the cells were investigated after 48 and 72 hours under an inverted microscope. Number of live cells and percentage of viable cells were determined by trypan blue exclusion test of cell viability. Cytotoxicity was assessed by MTT assay. Data analysis was performed by SPSS (version) 22 using one-way analysis of variance and Tukey's test at significance level of 0.05.
          Results: Secondary metabolites from the probiotic bacteria L. casei induced cellular differentiation, exerted anti-cancer effects and inhibited growth in K562 cells. Apoptotic cell death was confirmed by MTT and DNA fragmentation assays in a way that increasing the dilution from 1.2 to 1.32 significantly increased the viability of cells (P=0.001). In addition, increasing the dilution significantly increased the number of live cells in the first 48 hours (P=0.001).
        Conclusion: Culture supernatant of L. casei reduces the number of live cells, and induces apoptosis and monocytic differentiation in K562 cells in a dose- and time-dependent manner. Therefore, combined chemotherapy and differentiation therapy using such supernatants could be useful for treatment of cancer.
        Keywords: Cell differentiation, K562 cell line, Probiotic, Lactobacillus casei.
Shima Kazemi , Monir Doudi , Gholm Reza Amiri ,
Volume 11, Issue 6 (11-2017)
Abstract

ABSTRACT
           Background and Objectives: Development of ecofriendly processes for the synthesis of metal nanoparticles is of great importance in the field of nanotechnology. Microorganisms such as bacteria could be suitable candidates for bioproduction of nanoparticles due to their simplicity and high compatibility with the environment. The aim of this study was to use bacteria isolates from the effluent of wastewater treatment plants to produce silver nanoparticles.
         Methods: For identifying silver-resistant microorganisms, we used the agar diffusion method using PHG II medium containing 0.5 mM silver to determine minimum inhibitory concentration. Bacterial identification was done with biochemical testing and polymerase chain reaction (colony PCR). Finally, silver nanoparticles were produced in the desired bacteria, and the properties of these nanoparticles were studied.
         Results: We found five silver-resistant bacteria among which Stenotrophomonas maltophilia strain MS8 showed the highest resistance (MIC= 6 mM). The bacterium was able to synthesize silver nanoparticles in spherical shapes. The results obtained from visual observations using UV-VIS, TEM and XRD showed that the bacterium was able to reduce silver ions into silver nanoparticles with maximum size of 20 nm.
Conclusion: Based on our findings, this bacterium could be useful for biosynthesis of silver nanoparticles.
          KEYWORDS: Bacteria, Biosynthesis, Minimum Inhibitory Concentration. 

Amir Taghipoor Asramy , Abbas Ghanbari-Niaki , Shirin Hakemi , Mehran Naghizadeh Qomi , Mohammad Mehdi Moghanny Bashi ,
Volume 12, Issue 1 (1-2018)
Abstract

ABSTRACT
          Background and Objectives: The aim of this study was to evaluate the effect of 12 weeks of intense endurance training and bee pollen consumption on ABCA1 gene expression in small intestine, liver and gastrocnemius muscle tissues of male rats.
           Methods: In this study, 24 male Wistar rats (aged 6-8 weeks and weighing 90-110 g) were randomly divided into four groups of saline-control (n=6), saline-training (n=6), bee pollen-control (n=6) and bee pollen-training (n=6). The training groups exercised on a treadmill for 12 weeks (30 m/min, 90 min/day, five days/week). The bee pollen groups were given bee pollen orally (500 mg/Kg) for 12 weeks. Data were analyzed using two-way ANOVA at significance level of 0.05.
          Results: ABCA1 gene expression was highest in the liver, gastrocnemius muscle and small intestine, respectively. The findings also revealed that the intense endurance training caused a non-significant increase in ABCA1 gene expression in the small intestine and liver. However, the training caused a non-significant decrease in ABCA1 gene expression in the gastrocnemius muscle. In addition, consumption of bee pollen significantly increased ABCA1 gene expression in the small intestine and gastrocnemius muscle of male rats. However, the effect of bee pollen on the gene’s expression in the liver was not statistically significant.
           Conclusion: Based on our findings, it can be concluded that consumption of bee pollen has more beneficial effects on the ABCA1 gene expression and reverse cholesterol transport compared with the intense endurance training.
           Keywords: ABCA1 protein, Pollen, exercise.

Babisan Askari , Amir Rashidlamir , Asra Askari , Masoumeh Habibian , Arash Saadatniya ,
Volume 12, Issue 2 (3-2018)
Abstract

ABSTRACT
            Background and objectives: Cardiovascular disease is the leading cause of death worldwide. This study examined the effects of cardiac rehabilitation exercise on lipid profile and expression of peroxisome proliferator-activated receptor alpha (PPAR-α) gene in patients who underwent coronary artery bypass grafting.
           Methods: In this quasi-experimental study, after screening, patients who underwent coronary artery bypass grafting (CABG) were randomly divided into an experimental group (n=12) and a control group (n=12). After the surgery and discharge from hospital, the experimental group performed rehabilitation exercise for two months, while the control group did not perform any exercise after discharge from the hospital and the initial phase of rehabilitation. Fasting blood samples were collected before and after the last training session to evaluate biochemical variables and PPAR-α gene expression of lymphocytes. PPAR-α expression level was assessed by qRT-PCR. Statistical analysis was done in the SPSS software (version 20) using repeated measures.
            Results: In the follow-up after the two-month cardiac rehabilitation exercise, the PPAR-α gene was significantly overexpressed and plasma HDL levels increased significantly in the training group compared with the control group (P<0.05). Although the concentrations of LDL and triglycerides decreased in the experimental group, this reduction was not statistically significant (P>0.05).
            Conclusion: The results indicate that the protocols carried out in the study could be utilized for improving HDL levels and cardiovascular function in CABG patients.
            keywords: Cardiac Rehabilitation, Gene Expression, PPAR-α.


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