mohsen zargar

In recent years ulcerative colitis is a disease common has increased significantly. The risk factors of this disease include; genetic background, environmental factors and bacteria. The important factors in terms of genetic background are family history in first cousins, genetic markers and race and in terms of environmental factors is diet. Based on researches, it is identified that gastrointestinal microbiota is involved in the development of ulcerative colitis and one of the most important bacteria is Escherichia coli with pks gene. pks genomic island is frequently harboured by Escherichia coli strains of the B2 phylogenetic group. pks gene produces a genotoxin as secondary metabolite called colibactin which creates DNA damage in the epithelial cells in the intestine. Mammalian cells exposed to live pks+ bacteria exhibit DNA-double strand breaks and undergo cell-cycle arrest and death. In this study, we investigate the role of E. coli bacteria with pks gene as well as colibactin mechanism on the cell metabolism in the intestine.

It is important to increase lipid content with the aim of using it in food supplements and biodiesel. Changing the concentration of salinity and nitrogen is one of the important and practical strategies in this direction. Chlorella vulgaris EP33 microalga, isolated and identified from the waters of the northern regions of Iran, can be used as a lipid source. In this study, central composite design in Response Surface Methodology is used including 3 replications at the central point and 11 experiments to optimize lipid accumulation. Lipid content was measured. The results showed that the highest lipid content was obtained in the optimal conditions of nitrogen 10 and salinity 115 mM (0.503 g/g dry biomass) and the growth rate in these conditions was half of the optimal conditions in nitrogen 10 and zero salinity. The experimental values and the values predicted by the software also had logical relationships, which indicated the appropriateness of the used models as well as the compatibility of the Response Surface Methodology to determine the optimal conditions. By changing the concentration of some effective factors in lipid production, it can be used for economic optimization of lipid production with practical purposes. In this study, it was observed that nitrogen supply increases the tolerance level of microalgae to salinity as a practical way to increase lipid production. The results of optimization of process variables through response surface methodology reflect the leading research towards increasing lipid content using an economically efficient technological approach.

Successful delivery of a gene to a target cell requires the development of a safer and more efficient gene transfer system. This study aimed to evaluate the transfection efficiency of cationic virosome derived from vesicular stomatitis virus (VSV) as a hybrid nano-carrier compared to two commercial transfection reagents including Lipofectamine™ 2000 and, GenJet™ in HEK-293 and, Vero cell lines.

The transfection efficiency of VSV cationic virosome, Lipofectamine™ 2000, and GenJet™ was evaluated in HEK-293 and Vero cell lines using pEGFP-N1 plasmid transfection, fluorescent microscopy, and flow cytometry methods. Also, the toxicity of cationic virosome and commercial transfection reagents was investigated by the MTT test. The inhibitory effect of NH4Cl on virosome transfection efficiency was analyzed by fluorescent microscopy and flow cytometry.

Our findings showed that the highest level of EGFP expression was obtained in cells transfected with Lipofectamine™ 2000. Transfection efficiency was significantly increased in both cells transfected with virosome/pEGFP-N1 compared to pEGFP-N1/GenJet™ (P< 0.05, P< 0.01). In addition, the results of cell viability analysis by MTT were consistent with the results obtained from the evaluation of transfection efficiency. Cells transfected with lipofectamine™ 2000 showed the highest survival rate. Cell viability was significantly higher in cells transfected with VSV cationic virosomes compared to cells transfected with GenJet™ (P< 0.05). The results showed that transfection was inhibited in HEK-293 cells treated with NH4Cl.

VSV-derived cationic virosome containing VSV-G is an efficient hybrid nanocarrier with broad cellular tropism, which provides new insight into its application as a gene delivery system in gene therapy studies.

One of the factors causing colorectal cancer is infection with a specific strain of Escherichia coli (E.coli) that has a PKS genomic island with two clbB and clbN genes. One of the ways of human bacterial contamination is to consume vegetables irrigated with water contaminated with bacteria. These two genes cause the activation of the message transmission pathway and the DNA mutation and tumorigenesis by producing the toxin Bactin. The main aim of the present study is to investigate clbB and clbN genes in Escherichia coli isolated from vegetables irrigated with surface water and urban waste.

Vegetables irrigated with surface water, well and urban waste were collected from three regions of Tehran. Their E.coli bacteria were isolated and identified and confirmed. Then, PCR test was performed for clbB and clbN genes of all isolated E.coli bacteria.

The obtained microbial and biochemical results confirmed the E.coli bacteria isolated from the investigated vegetables. The molecular results showed that the highest and lowest frequencies for the samples that simultaneously contained both studied genes were related to vegetables irrigated with urban waste and vegetables irrigated with well water (P≤0.05). This result was almost the same for the vegetables of all three studied regions.

Considering the high frequency of E.coli bacteria isolated from vegetables irrigated with municipal waste and in order to prevent bacterial infection and consequently colorectal cancer, complete disinfection of vegetables and non-irrigation of vegetables in areas with waste are suggested. Keywords: E.coli, clbB, clbN, Vegetables, Urban waste, Surface water.

Recently, ciprofloxacin resistance in Staphylococcus aureus strains, due to efflux pumps, has become a significant challenge. Therefore, this study was performed to evaluate the frequency of norA, norB, and norC efflux pump genes and their roles in resistance to ciprofloxacin in clinical isolates of S. aureus.

A total of one hundred clinical blood samples were collected from patient in Qom hospitals and S. aureus isolates were identified by standard microbiological tests. Antimicrobial susceptibility patterns were determined by the disk diffusion method using CLSI guidelines. Subsequently, the presence of norA, norB, and norC efflux pump genes in ciprofloxacin isolates was detected using the PCR method.

Among one hundred clinical samples, 36 S. aureus isolates were recovered and the results of antibiotic susceptibility tests showed that twenty of them were resistant to ciprofloxacin. 15 isolates were resistant to norfloxacin and one isolate was resistant to ofloxacin. Moreover, the norA, norB, and norC genes were found in 58%, 30%, and 41% of ciprofloxacin-resistant isolates, respectively.

Based on the results of this study, norA, norB, and norC efflux pumps may play a significant role in the development of resistance to ciprofloxacin in clinical isolates of S. aureus. Detecting these genes may prove useful in suggesting an effective treatment model for infections caused by S. aureus.

Brucellosis is one of the most common diseases between humans and animals. Therefore, the need for prevention and production of an efficient vaccine is necessary. The aim of the present study is to prepare a niosomal nanostructure containing trivalent immunogen (TF, Bp26 and Omp31) of Brucella as a nanovaccine candidate.

In this study, after designing the immunogen structure by bioinformatics databases and software, in order to evaluate the immunogenicity of the designed recombinant protein, clone and gene expression were carried out in E.coli BL21. The protein extracted from the culture of said cells was purified by Ni-NTA column. Thin layer coating method was used to prepare niosomes carrying trivalent immunogen and were evaluated using DLS and Zetasizer characterization tests. Then, the amount of trivalent immunogen loading and release was calculated.

The results of the characterization confirmed the successful fabrication of niosomal nanosystem containing trivalent immunogen. The results showed that the produced niosomes are in a suitable range of size (100 nm). Trivalent immunogen with high efficiency (81.96%) is encapsulated in the system. The release of trivalent immunogen from Niosomal nanosystem was reported to be 97% after 96 hours. In addition, the trivalent immunogen release pattern of the coated system was more controlled and slower. This confirms the positive effect of the niosome nanosystem.

The use of nisome as a nanovaccine agent has an effective role in controlling antigen release and can be considered as a vaccine candidate and increase the protective immune response against Brucella.

As an important factor in pathogenicity, the ability of Staphylococcus aureus to produce biofilm increases its stability in the environment and living host. Biofilms formed by S.aureus, especially those related to the implant of medical devices, can act as a physical barrier against antibiotics and the host's immune system, leading to chronic or persistent infections. Hence, implementation of efficient diagnostic tests for the detection of biofilm formation can help reduce the disease burden. The purpose of this study was to assess different methods for the detection of biofilm formation in 40 S.aureus isolates.

A total of 40 non-duplicate S. aureus clinical isolates were identified. Biofilm formation was detected by Tissue Culture Plate (TCP), tube method (TM) and Congo red agar (CRA) methods and PCR assay was used to detect icaA and icaD genes. 

Among all S. aureus isolates, 21(52.5%) contained both icaA and icaD genes and icaD gene was present in all biofilm positive isolates. Tissue culture plate, Congo red agar, and tube method detected 30%, 42.5%, and 67.5% biofilm formation isolates, respectively.

According to the results, tissue culture plate with supplemented glucose showed the best correlation with the results of molecular assay and can be used as a reliable method to detect biofilm formation in clinical isolates of S. aureus.

Halophilic microorganisms have the potential to produce new biomolecules, including anti-cancer compounds, for medical applications. The purpose of this study was to evaluate the anti-cancer properties of pigments extracted from native Iranian halophilic Archaeon.

Pigment extract of Haloarcula sp. previously isolated and identified from Aran-Bidgol Lake was extracted. The effect of the extracted pigment on MDA-MB-468 breast cancer cell line was tested by MTT method and PI and FITC staining. Cells with different concentrations of pigment extract were incubated for 24, 48 and 72 hours. Finally, the expression of apoptotic genes, including BAX, CASP3, CASP7, CASP9, P21, P53, and SOX2, was examined by Real-Time PCR. Statistical analyses of the data were performed using the t-test and Repeated-Measures ANOVA.

Compared to untreated cells, the pigment extract inhibited the viability of MDA-MB-468 cells significantly after 48 hours at a concentration of 45.95 μg/ml (p*<0.05). In addition, the total population of early and late apoptotic cells (44.4%) increased in the studied cell line, which was associated with a
significant enhancement of the expression of the P53, BAX, CASP7, and CASP9 genes.

Halophilic archaea can be considered a suitable source of natural pigments with anti-cancer activity and potential benefits in chemotherapy.

Although there are different methods for the production of nanoparticles, today the synthesis of nanoparticles with biological methods has attracted the attention of researchers because it is an easy, environmentally friendly, and cost-effective method. The present study investigates the biosynthesis of gold nanoparticles using Lactobacillus paracasei (MN809528) exopolysaccharide and studies the antibacterial, anti-biofilm, and antioxidant properties.

For the synthesis of gold nanoparticles, 30 ml of 1% exopolysaccharide (0.1 g) solution was added to an equal volume of 1 mM aqueous HAuCl4 solution and mixed well using stirred (180 rpm) for 48 h at room temperature. The characterization of synthesized gold nanoparticles was performed using UV-VIS, FT-IR, DLS, XRD, EDX, FE-SEM spectroscopic analysis. Antibacterial activity of produced gold nanoparticles by agar well diffusion method, anti-biofilm activity by 96 well microplate dilution method, and antioxidant activity of nanoparticles using DPPH radical adsorption capability were examined.

Spectroscopic data showed the presence of a peak at 524 nm, which is specific to gold nanoparticles. Examination of the shape and size of nanoparticles with FE-SEM showed that the produced nanoparticles were spherical in shape and their average size is 2o-50 nm. Antibacterial activity of gold nanoparticles at a concentration of 50 µg /ml was observed against all bacterial tests. However, the highest antibacterial activity was observed against Acinetobacter baumannii (ATCC 17978). In the present study, the gold nanoparticles produced acted as biofilm and DPPH radical inhibitors.

The results of the study show that Lactobacillus paracasei (MN809528) is a good biological source for the synthesis of gold nanoparticles. The study is the first report on the production of gold nanoparticles by exopolysaccharides isolated from indigenous lactic acid bacteria.

Coronavirus disease 2019 spreads worldwide and needs detection systems capable of rapid diagnostic of this virus (SARS-CoV-2). The aim of this study is to design the homemade RT-PCR method for the Detection and phylogenetic analysis of this virus

The genes selected for diagnosis were E and M genes for this virus. PCR product was cloned in pTZ57R/T plasmid for preparation of positive control. In order to determine the sensitivity of this molecular method, the genes mentioned in the clone pTZ57R/T vector and the Limit of detection (LOD) the genes were determined and phylogenetic analysis was performed using partial E and M gene sequences.

PCR product was observed for E and M genes 156 and 547 bp on the Agarose gel. The LOD of the E and M gene was 60 and 82 copies. There was also a positive response to the samples of patients who were positive by other methods.

Since this virus is considered to be the cause of a pandemic in different countries all over the world, the present study is very important as a method of rapid and low-cost molecular diagnosis for monitoring this virus. Phylogenetic analysis is necessary for epidemiological studies for the control and prevention of the disease.

The presence of microbiome in the blood samples of healthy individuals has been addressed. However, no information can be found on the healthy human blood microbiome of Iranian subjects. The current study is thus aimed to investigate the existence of bacteria or bacterial DNA in healthy individuals.

Blood samples of healthy subjects were incubated in BHI broth at 37 °C for 72 h. The 16S rRNA PCR and sequencing were performed to analyze bacterial isolates. The 16S rRNA PCR was directly carried out on DNA samples extracted from the blood of healthy individuals. Next generation sequencing (NGS) was conducted on blood samples with culture-positive results.

Fifty blood samples were tested, and six samples were positive by culture as confirmed by Gram staining and microscopy. The obtained 16S rRNA sequences of cultured bacterial isolates revealed the presence of Bacilli and Staphylococcus species by clustering in the GeneBank database (≥97% identity). The 16S rRNA gene sequencing results of one non-cultured blood specimen showed the presence of Burkholderia. NGS results illustrated the presence of Romboutsia, Lactobacillus, Streptococcus, Bacteroides, and Staphylococcus in the blood samples of positive cultures.

The dormant blood microbiome of healthy individuals may give the idea that the steady transfer of bacteria into the blood does not necessarily lead to sepsis. However, the origins and identities of blood-associated bacterial rDNA sequences need more evaluation in the healthy population.

Canine parvovirus type 2 (CPV 2) suddenly appeared as a pathogen in dogs in the late 1970s, causing a severe and often fatal gastrointestinal illness. The original CPV 2 was replaced by three types of variants, CPV 2a, CPV 2b and CPV 2c, which to date have achieved global distribution in varying proportions. All previous studies in Iran were based on partial VP2 gene sequence. The aim of this study was to provide genome analysis to describe CPV strains collected in Tehran, Iran.

Rectal swab samples were collected in 2019 and tested using serological methods. Out of forty positive samples, nine samples were selected for further analysis using various molecular methods.

The results revealed a high prevalence of CPV-2a, CPV-2b and CPV2-C variants. Phylogenetic analysis showed that in Tehran the CPV 2b, CPV 2a and CPV-2 C strains were related to a cluster of specimens. Thus, the results suggested that CPV 2 sequences is not the results potential recombination events here.

Continuous monitoring and molecular characterization of CPV2 samples is necessary not only to identify possible genetic and antigenic changes that may interfere with the effectiveness of vaccines, but also to better understand the mechanisms of CPV 2 evolution in Iran.

Acroptilon repens (L.) DC is an Asian native plant belongs to the Asteraceae family. It has been cultivated the United States and Canada in recent years. This study investigated the effects of antibacterial, anti-biofilm, and cytotoxicity of A. repens ethanolic extract and its components.

We used disk diffusion and well diffusion strategies to screen antimicrobial activity of A. repens against Staphylococcus aureus and Staphylococcus epidermidis. Then, the minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) of extract and fractions were determined by the small dilution broth methodology forS. aureus and S. epidermidis. The impact of extract and fractions on biofilm formation was evaluated by microtiter plate assay The MTT assay determined the toxicity effect of samples on Vero cells. The results are expressed because of the viability.

Results showed that A. repens extract and fragments inhibit the growth of gram-positive bacteria. The ethanolic extract and its fractions showed stronger inhibition zones for S. aureus and S. epidermidis. According to the antibiofilm test, the ethanolic extract and water fraction of A. repens have the highest antibiofilm effect on S. aureus and S. epidermidis. The value of LC50 (50% mortality) in MTT assay results was 30, 60, 30, and 2/5 mg/mL for ethanolic extract, chloroform, ethyl acetate and water fractions of A. repens, respectively.

Extract of A. repens and its fractions have an antibacterial and antibiofilm effect on S. aureus and S. epidermidis without significant cytotoxic effect.

Klebsiella can cause urinary tract infections that is associated with drug resistance. Capsule production as a means of resistance can prevent host immune system responses. This study investigated the effect of a PLGA nanoparticles vaccine containing capsule antigen.

Vaccination of 20 mice with an age of 3-5 weeks (with a weight range of 22±18 g) was performed in four groups of capsules, PLGA, PLGA-capsule combination (PLGA+CPS) and control (PBS). In this study, the fabrication of nanoparticles was investigated by zetasizer and FITR tests. Microbial loading was also performed on the bladder.One-way analysis of variance and Tukey post hoc test were used for statistical analysis .

The results of confirmation tests of zetaiser showed that the nanoparticle size and the size of PLGA nanoparticles containing capsule antigen molecule were 178.7 and 159.4 nm, respectively.The result of FTIR and the shapes of the corresponding peaks confirmed the presence of antigen functional groups in the nanoparticle structure and the formation of ester bonds.The resut of FTIR test also indicates the success of PLGA nanoparticles containing capsule antigen , the results of microbial challenge showed that in the control and PLGA groups, due to the fact that PLGA nanoparticles vaccine contain capsule antigen were not used, a significant increase was observed in terms of the number of colonies compared to other groups  )p<0/05( .

PLGA nanoparticles containing capsule antigen molecules have a better ability than pure capsules and can significantly reduce tissue damage.

Influenza vaccines based on conserved proteins are being developed persistently. The conserved protein vaccines based on Nucleoprotein (NP) are highly protected vaccines against influenza viruses that can be used as a Universal vaccine. Aluminum hydroxide (Alum) is the most common adjuvant used in vaccine formulation to improve immunization by altering the epitopes’ folds. However, due to its toxic effects on the nervous system, especially in infants and young children exposed to multiple vaccine injections during brain development, it is better to use more desirable options such as carbohydrate-based adjuvants. Sucrose ester (SE) is a carbohydrate and non-ionic surfactant that is compatible with the human body and environmentally friendly. This study evaluated the immunogenicity of recombinant NP molecule prepared in a prokaryotic with the accompaniment of sucrose ester adjuvant against lethal influenza virus challenge in a Balb/c mice model.

The recombinant vector of PET-28a-NP was used to produce NP molecule. The vaccines containing an NP with or without Alum or sucrose ester adjuvants were injected into the mice. The Effectiveness and immunogenicity were examined by evaluating the humeral immunity induction by Immunoglobulin G (IgG), and its subunits production, and cellular immunity induction by Interferon-Gamma (IFN-γ) and Interleukin-4 (IL-4) production by ELISA Method and also animal’s surveillance was documented. The study took part at the Influenza and other respiratory viruses department of Pasteur institute of Iran in November 2018.

The animals’ surveillance in the Np group was 57.1%, NP+SE was (71.4%), and NP+SE was 64.28%. Also, IgG and its subunits, IL4, and IFN-γ production in both Alum and SE combined vaccines compared to NP alone were significant.

In combination with the carbohydrate adjuvant containing sucrose ester compared to the formulation with alum adjuvant, the NP could provide proper and considerable protection and immunity against the homologous strain (H1N1) of the Influenza A virus. It is recommended that SE usage as an adjuvant results in an adequate immune response and less toxic effect.

Background & Aims of the Study:

 This study aimed to investigate, for the first time, the ability of single-cell oil production from low-cost carbon sources using Kocuria Y205 native Iranian bacterial isolates from the soil.

Whey and lignocellulose compounds were used as carbon sources and yeast extract as a nitrogen source. Also, the isolated cultivation was done on Mineral Salts Medium (MSM) culture media. Molecular analysis based on 16s rRNA gene sequence was performed to identify isolated. Fourier-Transform Infrared Spectroscopy (FTIR) analysis was used to confirm the presence of carbon groups. GC analysis was also used to identify the fatty acids Sudan black. Finally, a Transmission Electron Microscopy (TEM) electron microscopy image was taken to view the stored lipid granule.

The highest rate of lipid production among all carbon sources in different periods of cultivation by whey was 24.57% after 48 hours, and also, the highest rate of lipid production for lignocellulose compounds was 15.29% after 48 hours.

This study shows that the newly isolated Kocuria Y 205 has excellent ability to use whey and lignocellulose compounds as waste containing carbon resources for the growth, production, and storage of microbial oil. It can be used in industrial applications, too.

Hepatitis B virus (HBV) is a human carcinogenesis agent. Interleukin 10 (IL-10) is a key anti-inflammatory cytokine, and single nucleotide polymorphisms in IL-10gene promoter are correlated with infections caused by HBV.This research intended to assess the prevalence and genotype of HBV as well as the association between the polymorphisms of -819 and -1082 in the IL-10 gene with HBV in individuals with HBV infection in Qom Province, Iran

In this cross-sectional research, 360individuals with chronic HBV infection and control group were involved between July2018 and March2019. HBV diagnosis was evaluated using ELISA and nested PCR assays. To determine polymorphisms in the IL-10 gene promoter in HBV positive and control samples, an allele-specific polymerase chain reaction technique was employed.

The constructed phylogenetic trees for the HBsAg gene revealed that all sequences under study belong to genotype D and also, the majority of HBV samples presented similar sequences to the Iranian samples. Genotype frequencies of TT, TC and CC (polymorphism -819) were 82.2%, 11.6% and 6.1% for patients and 85%, 10.5% and 4.4% in control groups, respectively. Also, frequency of genotypes of AA, AG and GG (polymorphism -1082) were 45%, 43.8% and 11.1% for patients and 42.2%, 46.1% and 11.6% in control groups, respectively.

Here, we found no association among IL-10 gene polymorphisms in control and HBV-infected groups. However, more studies about the frequency of chronic HBV infection are necessary to be conducted.

Multi-drug-resistant Enterobacter aerogenes is associated with various infectious diseases that cannot be easily treated by antibiotics. However, bacteriophages have potential therapeutic applications in the control of multi-drug-resistant bacteria. In this study, we aimed to isolate and characterize of a lytic bacteriophage that can lyse specifically the multi-drug-resistant (MDR) E. aerogenes.

Lytic bacteriophage was isolated from Qaem hospital wastewater and characterized morphologically and genetically. Next-generation sequencing was used to complete genome analysis of the isolated bacteriophage.

Based on the transmission electron microscopy feature, the isolated bacteriophage (vB-Ea-5) belongs to the family Myoviridae. vB-Ea-5 had a latent period of 25 minutes, a burst size of 13 PFU/ml, and a burst time of 40 min. Genome sequencing revealed that vB-Ea-5 has a 135324 bp genome with 41.41% GC content. The vB-Ea-5 genome codes 212 ORFs 90 of which were categorized into several functional classes such as DNA replication and modification, transcriptional regulation, packaging, structural proteins, and a host lysis protein (Holin). No antibiotic resistance and toxin genes were detected in the genome. SDS-PAGE of vB-Ea-5 proteins exhibited three major and four minor bands with a molecular weight ranging from 18 to 50 kD.

Our study suggests vB-Ea-5 as a potential candidate for phage therapy against MDR E. aerogenes infections.

the aim of this study was the isolation of phages able to lyse some strains of MDR-K. pneumoniae (named vB_Kp1 and vB_Kp2) and E. aerogenes (named vB_Ea1) from swages.

Different Klebsiella pneumoniae and Enterobacter aerogenesis strains isolated from clinical specimens (January to September 2018) in three Hospitals in Amol, (Mazandaran, Iran). Kirby Bauer’s disc diffusion method was used for determination of resistance profiles of these isolates using different antibiotics. The resistant strains to multi tested antibiotics (MDR) were selected to investigate the effect of isolated phages from wastewater and hospital sewage. Presence of phage investigated by plaque formation and after enriching and concentrating the isolated bacteriophages and staining the samples, a transmitting electron microscope (TEM) was used to observe the morphology of the bacteriophages. Phage identification tests including host range and One-step growth were performed.

 TEM analysis revealed that tree phages have an icosahedral capsid and long contractile tail. Therefore, they are a member of the Myoviridae family. Phages were able to lyse 14 (56%) of the 25 strains of multidrug-resistant bacteria isolated. The one-step growth curve showed large burst sizes and short latent times.

The formation of clear plaques shows the high lyse power of phages, so they have good potential for further analysis for clinical use as a therapeutic agent in the future.

Iran has a high incidence rate for gastric cancer among the Middle East countries. In addition to gastric cancer, peptic ulcer is also life-threatening; thus, investigating the prevalence of Helicobacter pylori infection and other risk factors are essential. The present study was aimed to assess the frequency of H. pylori and the cagA-positive strains in patients with gastric cancer or peptic ulcer at a teaching hospital in Qom, one of the most populated cities of Iran.

The presence of H. pylori was investigated in gastric cancer and peptic ulcer biopsy specimens using the standard culture method. PCR analysis was performed to detect the presence of the cagA gene.

The frequency of H. pylori isolates among 86 investigated biopsies was 20 (23.2%). Likewise, the rate of H. pylori was the highest when samples were examined from patients with gastric cancer (25.8%), while it was 21.8% when obtained from peptic ulcer patients. The frequency of the cagA gene in H. pylori isolates was 9 (56.2%), as confirmed by PCR.

Our results indicated that H. Pylori infection and its virulent strains are frequent and widely spread in Qom city. The cagA gene was present in almost half of H. pylori isolates from peptic ulcer or gastric cancer patients. Therefore, it is necessary to screen it in all cases with H. pylori infection for early detection of gastric cancer.

The last two decades witnessed the spread of the first generation of influenza viruses. Influenza virosomes are promising tools in vaccine and immunotherapy programs because of their applications in various medical fields. The aim of the present study was to construct cationic virosomes derived from
influenza virus using dialyzable detergent (DCPC) and cationic lipid (DOTAP) in vitro.

Influenza A / Puerto Rico / 34.8 (H1N1) strain was propagated in MDCK cell line. The influenza virus envelope was dissolved using DCPC as a dialyzable detergent, and finally it was removed by dialysis and the cationic virosome was synthesized through adding cationic lipid (DOTAP). Cytotoxicity and presence of HA and NA proteins were evaluated by cell viability assay (MTT assay) and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), respectively. Also, macroscopic and morphology studies of virosomes were performed by transmission electron microscopy (TEM).

The final concentration of virosomes was 1.5 mg/ml. The presence of HA and NA proteins was confirmed by SDS-PAGE. Cell survival was significantly decreased after 48 hours of treatment with
different concentrations of cationic virosomes (P<0.05).

The use of a detergent (DCPC) and also a cationic lipid (DOTAP) is an effective procedure for reconstruction of influenza virus envelope without any alteration in surface glycoproteins (HA, NA). The methoed used in the present study for producing influenza virosome will be a promising candidate for
developing influenza vaccines.

Microorganisms that store lipids due to nutrient deficiencies (especially nitrogen) produce microbial oils following inhibition of growth. Based on the structure of fatty acids, microbial oils have industrial applications. The main purpose of this study, the first in Iran, was to evaluate the production of single-cell oil from Rhodococcus erythropolis PTCC 1767 using low-cost materials.

In the present study, Rhodococcus erythropolis PTCC 1767 as bacterial strain, whey, wheat straw, glucose, and glycerol were used for carbon sources and yeast extract was used for the nitrogen source. The bacterial strain was cultured in the MSM medium. FTIR analysis was performed to confirm the presence of carbon groups, GC analysis for identifying fatty acids, and Sudan black staining and imaging with a Transmission Electron Microscope (TEM) for observing the lipid granules stored inside the cell.

The highest lipid production in the presence of carbon sources was related to whey in 96 hours with 23.22% and the maximum lipid production was obtained using wheat straw in 72 hours with 20%.

The results of the present study demonstrated that Rhodococcus strains have the ability of bioconversion of low-cost carbon sources wheat straw and the whey to microbial oils and this can serve as a platform for eco-friendly biotechnological processes.

Nowadays, one of the barriers of gene therapy in the treatment of the CNS diseases is the lack of proper and safe carrier systems to cross the blood brain barrier (BBB). Virosomes are virus like particles which can be used in brain if made from neurotropic viruses. The aim of the study was to construct cationic virosomes derived from vesicular stomatitis virus using dialyzable short chain phospholipid (DCPC) and cationic lipid (DOTAP) in-vitro.

The vesicular stomatitis virus was propagated in Vero cell line. Subsequently, the harvested virus was concentrated and purified using ultrafiltration and ultracentrifugation and finally, the virosome was synthesized by DCPC detergent and the addition of cationic lipid. Particle size distribution of virosome nanoparticles, cellular cytotoxicity and glycoprotein of vesicular stomatitis virus (VSV-G) were determined by measuring dynamic light scattering using zetasizer, MTT assay and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), respectively.

The harvested viruses were concentrated and purified by ultrafiltration and ultracentrifugation and the final concentration was 0.8 mg/ml. The cationic virosome mean size was 186.6 nm and, the cell viability was significantly decreased after 48 hours of treatment with different concentrations of virosome compared to the control group. The VSV-G protein with molecular weight of 63 kDa was approved by SDS-PAGE.

The use of DCPC is an efficient method for solubilization and reconstruction of vesicular stomatitis virus envelope and does not alter the surface VSV-G. Due to the VSV-G protein and its wide range cell tropism, this cationic virosome can also be a promising candidate for crossing the BBB in order to efficient gene delivery and therapy of CNS diseases.

 Hepatitis B virus (HBV) and hepatitis D virus (HDV) infections are known as major health concerns world-wide. Nucleoside analogs (NAs) are widely used in anti-HBV therapy. However, HBV resistance to Nas may result in disease recurrence.

 The present study aimed to evaluate the prevalence of HBV and HDV infections, and to investigate the presence of YMDD motif in HBV-infected patients.

 In this cross-sectional study, a total of 1600 blood specimens were collected from HBV-suspected patients, who referred to diagnostic centers in Qom Province, Iran from July 2018 to March 2019 before and after lamivudine therapy. The presence of HBV in the specimens was investigated using ELISA and nested PCR assays. Also, HDV and YMDD motif were detected in HBV-infected patients using the PCR technique. In order to confirm the presence of HDAg gene of HDV, the PCR products of some HBV/HDV-positive specimens were subjected to direct sequencing.

 The number of HBsAg positive patients was 180 (11.25%) (P < 0.05) according to ELISA and nested PCR assays; these patients were in the age range of 32 - 38 years. Also, 11 (6.1%) patients were infected with HBV/HDV. The frequency of lamivudine resistance mutation in the YMDD region was 28 (15.5%) among chronic HBV patients. The constructed phylogenetic trees for HDAg gene of HDV showed that most HBV/HDV isolates had similar sequences to the Iranian isolates.

 The present results showed that it is important to increase our knowledge about the frequency of chronic HBV and HDV infections. Also, development of new antiviral medications is important for prevention and prompt and appropriate treatment.