ABSTRACT
Background: Design of experiments is a rapid and cost-effective approach for optimization of recombinant protein production process. In our previous study, we generated a potent dual-acting fusion protein, anti-CD22 scFv-apoptin, to target B-cell malignant cell lines. In the present investigation, we report the effect of different variables on the expression levels of this fusion protein
Methods: Four variables [cell optical density at induction, IPTG concentration, induction temperature, and induction time] were tested using experimental design
Results: Our findings demonstrated that among the examined variables, only the induction time had a significant positive effect on the protein expression yield
Conclusion: Experimental design was successfully applied in this study. The optimized condition obtained in the current study can be applied in future commercial production of this novel fusion protein
ABSTRACT
Bakground: Aspergillus fumigatus is an airborne opportunistic fungal pathogen that can cause fatal infections in immunocompromised patients. Although the current anti-fungal therapies are relatively efficient, some issues such as drug toxicity, drug interactions, and the emergence of drug-resistant fungi have promoted the intense research toward finding the novel drug targets
Methods: In search of new antifungal drug targets, we have used a bioinformatics approach to identify novel drug targets. We compared the whole proteome of this organism with yeast Saccharomyces cerevisiae to come up with 153 specific proteins. Further screening of these proteins revealed 50 potential molecular targets in A. fumigatus. Amongst them, RNA-binding protein [RBP] was selected for further examination. The aspergillus fumigatus RBP [AfuRBP], as a peptidylprolyl isomerase, was evaluated by homology modeling and bioinformatics tools. RBP-deficient mutant strains of A. fumigatus were generated and characterized. Furthermore, the susceptibility of these strains to known peptidylprolyl isomerase inhibitors was assessed
Results: AfuRBP-deficient mutants demonstrated a normal growth phenotype. MIC assay results using inhibitors of peptidylprolyl isomerase confirmed a higher sensitivity of these mutants compared to the wild type
Conclusion: Our bioinformatics approach revealed a number of fungal-specific proteins that may be considered as new targets for drug discovery purposes. Peptidylprolyl isomerase, as a possible drug target, was evaluated against two potential inhibitors and the promising results were investigated mechanistically. Future studies would confirm the impact of such target on the antifungal discovery investigations
ABSTRACT
Background: endoscopic submucosal dissection [ESD] is a novel technique for removal of early mucosal neoplasms of gastrointestinal tract. While it has been widely used in Japan and eastern Asian countries, there have been no data available from Iran. Here we report our experience with this method in a single, private, non-tertiary care, and non-referral hospital in Iran
Materials and Methods: demographics, outcomes, and complications of ESD of six lesions in six patients performed at a single center during 2013-2016 were retrospectively evaluated
Results: the mean [range] age of the patients was 60.5 [40-71] years. Of them three had gastric lesions and three had rectal lesions. Two gastric lesions were HGD [High Grade Dysplasia] and one was intramucosal carcinoma. Rectal lesions were villous adenoma in one case and two T1 adenocarcinomas in two other cases. The mean [range] size of the lesions size was 3.1 cm [2.5-8 cm]. Complete removal was achieved in all the patients both endoscopically and histopathologically. Microscopic perforation occurred in one case, which was managed conservatively without a need for surgical intervention. No significant late bleeding was observed. No surgery was needed either for completion of removal or control of complications. During mean follow-up of 20 months no recurrence occurred
Conclusions: our first experience with ESD shows its high rate of effectiveness with acceptable complication rate and success rate. Proper patient selection and use of standard techniques and instruments are required to produce clinically acceptable outcomes for patients in need of this method to cure their early mucosal neoplasia
ABSTRACT
Background: Starting to work from early age can have negative impact on the growth and nutritional status, especially if the children are employed in dangerous jobs. This study aimed to assess nutritional status and growth in working children who were working in Kermanshah.
Materials and Methods: This survey was a case-control study that wasdoneon90 working childrenand90not- working children in Kermanshah. Information related to anthropometric indices with measurements of height and weight, demographic data using demographic questionnaire and food intake using food frequency questionnaire were collected. To compare growth of children with standards we use body mass index percentiles for sex and age provided by Centres for Disease Control and Prevention [CDC].Data analysis was performed using SPSS software version 16.
Results: Mean of age working children was 16.4 +/- 1.8 years and 15.7% of them were illiterate. Consumption of all food groups except the miscellaneous group in working children was significantly lower than not- working children[p<0.001].The prevalence of stunting in working children was 10% more than the not- working children. The prevalence of malnutrition based on body mass index in working children[36.1%], was approximately 50% more than the not- working children[16.5%], [P <0.01].
Conclusion: The finding so this study showed that indicators of nutritional status in working children have not favourable condition. This could bea risk factor for health of this group of children and a warning for affecting of them by kind of disease.
ABSTRACT
Infectious Bursal Disease Virus [IBDV] causes a highly immunosuppressive disease in chickens and is a pathogen of major economic importance to the poultry industry worldwide. The VP2 protein is the major host-protective immunogen of IBDV and has been considered as a potential subunit vaccine against the disease. VP2 coding sequence was cloned in an inducible fungal vector and the protein was expressed in Aspergillus niger [A. niger]. Aiming at a high level of expression, a multicopy AMA1-pyrG-based episomal construct driven by a strong inducible promoter, glaA, was prepared and used in transformation of A. niger pyrG[-] protoplasts. SDS-PAGE and western blot analysis was carried out to confirm the expression of the protein. A number of pyrG[+] positive transformants were isolated and the presence of expression cassette was confirmed. Western blot analysis of one of these recombinant strains using monospecific anti-VP2 antibodies demonstrated the successful expression of the protein. The recombinant protein was also detected by serum obtained from immunized chicken. In the present study, we have generated a recombinant A. niger strain expressing VP2 protein intracellulary. This recombinant strain of A. niger may have potential applications in oral vaccination against IBDV in poultry industry
Subject(s)
Animals , Infectious bursal disease virus , Recombinant ProteinsABSTRACT
Bone morphogenetic protein-7 [BMP-7] is a multifunctional growth factor predominantly recognized for its osteoinductive properties. Due to the high cost of this protein, the availability of BMP-7 for treatment is limited. The heterologous production of recombinant hBMP-7 has been performed in a number of expression systems. In this study a novel form of BMP-7 was expressed in eukaryotic and prokaryotic hosts. For expression in the prokaryotic system, the novel protein was secreted to the periplasmic space of Escherichia coli using a pelB signal sequence followed by singlestep purification by Ni2+-charged column chromatography. In the mammalian cell expression system, we transferred a full-length cDNA encoding precursor of the novel protein to CHO cells then selected stable clones by using the appropriate antibiotic concentration. Expressions in both systems were confirmed by Western blot analysis. The novel recombinant protein was produced as a 36-38 kDa dimer in the CHO cell line and a 16 kDa monomer in the Escherichia coli system. Quantitative analysis according to ELISA showed that the expression levels of the mutant protein in the eukaryotic and prokaryotic expression systems were 40 ng/ml and 135 ng/ml of the culture media, respectively. In this study, the expression level in Escherichia coli was at least three times more than observed in the CHO cells. However, further optimization is required to obtain a dimer protein in Escherichia coli. The results show that periplasmic expression may be suitable for the production of complex proteins such as BMPs
Subject(s)
Prokaryotic Cells , Eukaryotic Cells , Mutant Proteins , Escherichia coli , CHO CellsABSTRACT
Infertility can be a major concern for couples trying to conceive, and occupational hazards may constitute a main cause of infertility in men. Studies conducted throughout the world indicate that physical and chemical hazards in the workplace can have a negative impact on male fertility. The main objective of this study was to determine the frequency of occupational categories of men who attended an infertility clinic, and to evaluate the differences in the semen quality parameters among occupational categories. This cross-sectional study was conducted on 1164 males who were referred to the Infertility Research Center in Tehran for treatment of infertility in order to evaluate the effects of certain occupations on infertility. The participants were divided into several categories according to their occupations and evaluated by means of a questionnaire for duration of infertility, BMI, sperm count, percentage of normal sperm morphology and percentages of sperm with class A and class B motilities. Descriptive statistics, analysis of variance, and correlations were conducted using SPSS 16.0 for Windows. There were no statistically significant differences in the mean sperm count or sperm morphology between occupational categories. Assessment of the differences in the frequency of sperm motility classes between occupational categories revealed a significant difference only in the frequency of sperm with class B motility. The lowest mean percentages of sperm with class B motility were seen in those involved in the transportation industry, a finding in agreement with a number of other researches. Our findings revealed an association between occupation and sperm motility. Since our study population was relatively small and in many cases exposures to work hazards were brief, a larger study group must be evaluated in order to support the preliminary results of this study
ABSTRACT
DNA coding for the core antigen from hepatitis B Virus [HBcAg] was amplified, cloned and propagated in E. coli. The core protein was expressed in E. coli and the product was readily detected by Western blot. This protein can be used as a diagnostic material in serum screening tests. To increase the level of expression of this antigen in bacteria, two plasmids were constructed in which the gene coding for Nterminal part of the human IL-2 has been fused to 5'-terminus of the core antigen gene under control of the tryptophan promoter. Although the expression level of core antigen from hepatitis B Virus in E. coli was increased in fusion forms, but the size of fusion partner could affect the antigenicity, particle formation and assembly of the core antigen. The native and the two fusion forms of the core antigens from hepatitis B Virus were evaluated as a diagnostic material in serum screening