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Brucella is a facultative intracellular gram-negative coccobacillus. It is nonsporulating and reproduced in macrophage phagosomes. The use of nanostructures as drug and vaccine carriers has recently received attention due to their ability to control the release profile and protect the drug molecules. This study presents a suitable nano-polyethyleneimine formulation to be used as an immunoadjuvant and LPS along with trivalent candidate antigens of TF, BP26, and omp31 to selectively stimulate the immune response. After designing and evaluating the immunogenic structure by databases and bioinformatics software, recombinant protein cloning and gene expression were performed in Escherichia coli BL21 bacteria. This protein was extracted from the cultured cells, purified by Ni–NTA column. After placing the antigen inside the polyethyleneimine nanostructure, various properties of the nanoparticles, including their size, zeta potential, and retention rate for injection and inhalation of mice, diffusion efficacy, and antigen binding evaluation were evaluated. Mice were treated with different groups of antigens and nanoparticles on days 0, 10, 24, and 38. Two weeks after the last injection, the level of cytokines were investigated in spleen cells, including IFN-γ, IL-4, and IL-12. The serum concentration of IgG2a and IgG1 antibodies were also assessed. The response was consistent with significant production of IgG1, IgG2a, IFN-γ21, IL-12, and IL-4 compared to the controls (P < 0.05). Compared to the positive and negative control groups, recombinant protein and nanoparticles showed a good response in subsequent injections with live bacterial strains. The present study also revealed the potential of the developed recombinant protein as a candidate in the design and manufacture of subunit vaccines against Brucella species. This protein stimulates cellular and humoral immune responses compared to the positive control groups. These findings can be useful in the prevention and control of brucellosis and pave the way for further research by researchers around the world. [ABSTRACT FROM AUTHOR]

As an important source of human food, milk can be a carrier of human pathogenic bacteria, including tuberculous and nontuberculous mycobacteria (NTM), in its raw and unpasteurized state. In this research, 175 raw milk samples and 175 traditional cheese samples were collected from traditional dairy stores in 22 regions of Tehran in a 9- month period from August 2019 to May 2020. Samples were prepared and transferred to a specialized laboratory, where they were inoculated in Lowenstein-Jensen (LJ) medium containing glycerol or sodium pyruvate, as well as Herrold's egg-yolk with and without Mycobactin J. to determine the sample's identity of samples. The recommended 16S rRNA (1436 bp) and hsp65 (644 bp) gene fragments from the positive isolates identified in Ziehl–Neelsen (Z-N) staining were amplified and sequenced using PCR and compared with the sequences of the gene fragments of reference strains available in the global GenBank database. No mycobacterial species were isolated from traditional cheese samples in microbial culture. In case of raw milk samples, a total of four bacteria were collected, all of which were found in the genetic differential testing to be NTM, including n = 1 Mycobacterium heraklionense, n = 2 Mycolicibacterium fortuitum, and n = 1 Mycobacterium thermoresistibile. The analysis of the results obtained by isolate sequencing using the 16S rRNA gene showed higher discriminatory power and percentage similarities in the identification of the isolates than the hsp65 gene. [ABSTRACT FROM AUTHOR]

Recently, opportunistic pathogens like Acinetobacter baumannii and Pseudomonas aeruginosa have caused concern due to their ability to cause antibiotic resistance in weakened immune systems. As a result, researchers are always seeking efficient antimicrobial agents to tackle this issue. The hypothesis of the recent study was that probiotic products derived from bacteria would be effective in reducing drug resistance in other bacteria. This research aimed to investigate the antimicrobial properties of probiotic products from various bacterial strains, including Lactobacillus rhamnosus, Pediococcus acidilactisi, Bacillus coagulans, Bacillus subtilis, and Bacillus licheniformis. These were tested against multi-drug-resistant (MDR) standard strains A. baumannii and P. aeruginosa. B. licheniformis was found to be the most effective probiotic strain, possessing the LanA and LanM lantibiotic genes. The lipopeptide nature of the probiotic product was confirmed through high-performance liquid chromatography (HPLC) and Fourier-transform infrared spectroscopy (FTIR) techniques. The anti-biofilm and antimicrobial properties of this probiotic were measured using an SEM electron microscope and minimum inhibitory concentration (MIC) test. Real-time PCR (qPCR) was used to compare the expression of bap and luxI genes, which are considered virulence factors of drug-resistant bacteria, before and after treatment with antimicrobial agents. The MIC results showed that the probiotic product prevented the growth of bacteria at lower concentrations compared to antibiotics. In addition, the ΔΔCqs indicated that gene expression was significantly down-regulated following treatment with the obtained probiotic product. It was found that B. licheniformis probiotic products could reduce drug resistance in other bacteria, making it a potential solution to antibiotic resistance. [ABSTRACT FROM AUTHOR]

Background: In the biological method, using nonpathogenic and extremophile bacteria systems are not only safe and highly efficient but also a trump card for synthesizing nanoparticles. Halomonas elongata QW6 IBRC-M 10,214 (He10214) and Salinicoccus iranensis IBRC-M 10,198 (Si10198), indigenous halophilic bacteria, can be used for synthesizing selenium nanoparticles (SeNPs). Methods: SeNP biosynthesis was optimized in two halophilic bacteria and characterized by UV–Vis, Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), X-ray powder diffraction (XRD), zeta potential, and energy dispersive X-ray (EDX). Results: Optimized conditions for synthesizing SeNPs was at 300 °C at 150 rpm for 72 h and 6 mM or 8 mM concentration of Na2SeO3. UV–Vis indicated a sharp absorption peak at 294 nm. Spherical-shaped nanoparticles by a diameter of 30–100 nm were observed in FESEM and TEM microscopy images. The produced SeNPs were identified by a peak in FTIR spectra. In XRD analysis, the highest peak diffraction had a relationship with SeNPs. The zeta potential analysis showed SeNP production, and elemental selenium was confirmed by EDX. Conclusions: Halophilic bacteria, owing to easy manipulation to create optimization conditions and high resistance, could serve as appropriate organisms for the bioproduction of nanoparticles. The biological method, due to effectiveness, flexibility, biocompatibility, and low cost, could be used for the synthesis of reproducible and stable nanoparticles. [ABSTRACT FROM AUTHOR]

Despite the huge efforts of microbiologists, infectious diseases have yet remained one of the leading causes of death in humans, further highlighting the research priority for controlling opportunistic pathogens. Many researchers have used antibacterial peptides to solve the problem of antibiotic resistance. This research is thus conducted to investigate the antibacterial and anti-biofilm activity of a novel modified cecropin–melittin 11-peptide with improved therapeutic properties and lower side effects. After synthesis and purification of mCM11 (NH2-WRLFRRILRVL-NH2) by solid-phase synthesis and HPLC methods, respectively, the antibacterial and biofilm inhibitory activities were explored in vitro. TMHMM was used to confirm the reaction of mCM11 on the plasma membrane of the prokaryotic cells. The interaction between mCM11 on Acinetobacter baumannii strains was investigated by molecular docking using ClusPro2.0. Hemolysis and therapeutic indexes were also calculated to quantify the relative safety and adverse effects of mCM11. According to the results, mCM11 has a high inhibitory and lethal effect on A. baumannii strains due to its cationic properties and new specific sequence. Molecular docking revealed the release of a significant amount of energy when mCM11 binds to the surface of A. baumannii in an appropriate site. The findings indicated that mCM11 IC50 (4 μg/mL) lysed 2.78% of RBCs; moreover, 8 strains of Acinetobacter baumannii showed a favorable therapeutic index. The mCM11 exhibits strong antibacterial and antibiofilm activities against A. baumannii strains, suggesting its potential therapeutic role in infections caused by these strains. Similar to its impact on A. baumannii, mCM11 could be a suitable alternative to antibiotics in combat against antibiotic-resistant bacteria in the in vivo experiments. [ABSTRACT FROM AUTHOR]

The problems of drug resistance in bacteria have become one of the daily challenges of the clinical treatment of patients, which inevitably forces us to use agents other than common antibiotics. Among these, we can take help from different properties and applications of nanoparticles (NPs). In this work, we evaluate the antibacterial activity of biosynthesized selenium nanoparticles (SeNPs) against standard strains of multidrug‐resistant Pseudomonas aeruginosa and Acinetobacter baumannii. The production of biosynthesized SeNPs was proved by ultraviolet‐visible, Fourier transform infrared, X‐ray diffractometer, Field Emission Scanning Electron Microscopy, Dynamic light scattering, and Zeta potential methods. The cytotoxicity effect of SeNPs was investigated by MTT assay. Disk diffusion agar (DDA) and minimum inhibitory concentration (MIC) tests were performed on the mentioned bacteria using different classes of standard antibiotics and SeNPs separately. The impact of SeNPs combined with the desired antibiotics for better treatment of these infections was evaluated by checkerboard assay to determine the synergism effect. After the confirmation results based on the biosynthesis of SeNPs, both standard bacterial strains were susceptible to SeNPs and had a zone of inhibition using the DDA test. Also, the results of MICs showed that biosynthesized SeNPs in lower concentrations than antibiotics cause no growth of bacteria. On the other hand, according to the checkerboard assay, SeNPs had a synergistic effect with conventional antibiotics. The antibacterial sensitivity tests demonstrated the inhibition of bacterial growth in the presence of lower concentrations of SeNPs than common antibiotics. This property can be exerted in future applications to solve the drug resistance obstacle of microorganisms in bacterial diseases. [ABSTRACT FROM AUTHOR]

Objectives: 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. Materials and Methods: 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 for S. 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: 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. Conclusions: Extract of A. repens and its fractions have an antibacterial and antibiofilm effect on S. aureus and S. epidermidis without significant cytotoxic effect. [ABSTRACT FROM AUTHOR]

The application of biological nanoparticles (NPs) can be considered as a way to overcome the problem of antifungal resistance in pathogenic fungi. This study takes a new approach to biosynthesized NPs influence on the expression of CYP51A and HSP90 antifungal resistance genes in Aspergillus fumigatus and A. flavus, and comparison with antifungal agents. Selenium NPs (Se‐NPs) were biosynthesized using Aspergillus strains and their production was proved by several methods including, UV–Vis, XRD, FTIR, FESEM, and EDX techniques. The minimum inhibitory concentrations (MICs) of Aspergillus strains were determined using the CLSI M38‐A2 broth microdilution method. The differences in expression levels of CYP51A and HSP90 genes were examined between untreated and treated of A. fumigatus and A. flavus using itraconazole and amphotericin B and biosynthesized Se‐NPs through real‐time PCR. After confirming the results of NPs synthesis, the MIC of itraconazole and amphotericin B against A. fumigatus and A. flavus was 4 μg/ml. Based on the real‐time PCR results, the obtained ∆∆CTs for these strains were −0.18, −1.46, and −1.14. Whereas the MIC values for treated samples with Se‐NPs have decreased to 0.5 μg/ml, and the ∆∆CTs for these were −0.25, −1.76, and −1.68. The expression of CYP51A and HSP90 genes was significantly down‐regulated through the use of Se‐NPs against A. fumigatus and A. flavus. [ABSTRACT FROM AUTHOR]

The biosynthesis of nanoparticles stands as an uncomplicated, biocompatible, inexpensive, and secure approach for replacing the available chemical and physical methods. In this paper, Selenium nanoparticles (Se-NPs) and silver nanoparticles (Ag-NPs) were biosynthesized using Nepeta and Berberine plant extracts, respectively. UV–Vis, FT-IR, and FESEM/EDAX techniques were applied for confirming the synthesis of nanoparticles. In addition, the method of Minimum Inhibitory Concentration (MIC) was utilized to perform a sensitivity test on fungal species' leachates through the usage of Duplicate. The application biosynthesized Se-NPs and Ag-NPs at concentrations of 1 µg/mL and below caused no growth of fungal agents. However, antifungal drugs at concentrations higher than 1 µg/mL and even up to 64 µg/mL inhibited the growth of these drug-resistant fungi. A comparison of the results showed that even these nanoparticles in some cases have a better effect than the group of antifungal drugs. Therefore, the usage of biosynthesized nanoparticles is considered to be more convenient and economical due to the increasing drug resistance of opportunistic and pathogenic microorganisms towards the exerted target drugs. [ABSTRACT FROM AUTHOR]

Biosynthesis of nanoparticles can replace the available chemical and physical methods by offering new procedures as green syntheses that have proved to be simple, biocompatible, safe, and cost‐effective. Recently, antifungal resistance has been reported against different species of Aspergillus and Candida opportunistic fungi. Selenium nanoparticles (Se‐NPs) were biosynthesized using standard strains of A. flavus and C. albicans. The presence of NPs was confirmed by UV‐Vis, FT‐IR, FESEM, EDX, XRD, and Zeta potential. Common fungal strains were cultured in Sabouraud dextrose agar medium to perform the sensitivity test based on the minimum inhibitory concentration (MIC) method in duplicate. The utilization of Se‐NPs at concentrations of 1, 0.5, and 0.25 μg/mL or in some strains even more minor than 0.125 μg/mL resulted in zero growth of fungal agents. However, antifungal drugs inhibited their growth at concentrations of 2, 4, 8, 16, and 64 μg/mL itraconazole (ITC). Also, MIC breakpoints for amphotericin B (AMB) and anidulafungin (AFG) were 2 μg/mL for defining resistance in some isolates. Based on the obtained results, biological NPs produced by Aspergillus and Candida at different concentrations exhibited favourable inhibitory effects on the growth of fungal strains. [ABSTRACT FROM AUTHOR]

Background: Drug resistant Acinetobacter baumannii have emerged as a major problem in many hospitals and intensive care units. The aim of this study was to determine the antibiotic resistance pattern and the prevalence of metallo-beta-lactamase genes among nosocomial A. baumannii isolates from Qom/ Iran. Methods: For this study, a total of 108 A. baumannii isolates were collected from hospitalized patients in four teaching hospitals of Qom/ Iran. Antibiotic susceptibility profile of isolates was tested by Kirby-Bauer disc diffusion method and distribution of MBL genes among carbapenemresistant isolates was determined by polymerase chain reaction (PCR) method. Results: According to the results, 97 (89.81%) isolates of 108 A. baumannii isolates were resistant to carbapenem. All isolates carried bla oxa-51like gene. Among carbapenem resistant isolates, 79.38% carried bla VIM and 1.03% had bla IMP genes. Among the MBL- producing isolates, 7 isolates were MDR, 73 ones were XDR and 5 isolates were PDR. Conclusion: This study also revealed that suceptibility to carbapenems in the population of A. baumannii isolates reduced and the bla VIM gene was the most prevalent metallo-beta-lactamase genotype among carbapenem resistant A. baumannii isolates in this area. MBL-producing A. baumannii in recent years has become a serious concern. Rapid identification and good infection control are requiered to reduce their impact. [ABSTRACT FROM AUTHOR]

Drug-resistant infectious diseases have increased in recent years. Accordingly, plenty of researches are exploring novel approaches to overcome this problem. In this era, antimicrobial peptides have been identified as potential antibacterial agents. The Modified CM11 (mCM11) was designed with the C-terminal amidation and substitution of lysine with arginine. The designed peptide was synthesized by the solid-phase method and Rink amide p-methyl-benzhydryl amine resin. The synthesized peptide was evaluated using Mass Spectrometry (MS), High-Performance Liquid Chromatography (HPLC), and Circular Dichroism (CD). Finally, the antibacterial, cytotoxic, and apoptotic effect of the mCM11 peptide was investigated. The new peptide indicated a beta-sheet structure with a molecular weight of 1527.50 D and purity of 96%. The peptide exerted a potent antimicrobial activity against gram-negative and positive bacteria. The minimum inhibitory concentration (MIC) and minimum bacterial concentration (MBC) ranged from 16 to 64 µg/ml, and 16 to 128 µg/ml, respectively. The IC50 of mCM11 was 16 µg/ml and its cytotoxicity in SH-SY5Y cell line revealed a dose-dependent manner. Also, apoptosis analysis of eukaryotic cells revealed a decline in late apoptosis and necrosis in comparison with untreated cells. The mCM11 indicated a considerable antibacterial effect against a wide range of pathogenic bacterial strains. Further, it did not represent any late apoptotic and necrosis impact on the eukaryotic cell line. All of these findings may confirm the potential role of this new peptide as an effective therapeutic agent. [ABSTRACT FROM AUTHOR]

Background: 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. Materials and Methods: 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. Results: 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. Conclusion: 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. [ABSTRACT FROM AUTHOR]

Background and Objective: The prevalence of the infections caused by Candida species has led to a significant increase in their resistance to antifungal compounds. The aim of this study was to i) investigate drug resistance ii) evaluate the incidence of Candida albicans drug resistance pattern in the vaginal samples of women referring to health centers of Qom province, and iii) examine the effect of Zn nanoparticles combined with fluconazole against C. albicans isolates. Methods: This experimental, descriptive study was performed on 120 patients of candidiasis. In order to identify Candida albicans, direct experiments, differential culture, Germ tube test and sugar assimilation test (API20C kit) were conducted. The effect of different antifungal drugs and zinc nanoparticles and the synergistic effect of fluconazole with zinc nanoparticles were investigated by disk diffusion method. Minimum Inhibitory Concentration (MICs) of all cases was further specified. Results: Of the 120 samples, 50 (41.6%) were identified as Candida albicans. These strains were resistant to certain antifungal drugs while others were semi-sensitive and sensitive. The lowest and the highest mean diameter of inhibition zone in all Candida albicans isolates belonged to ketoconazole (15.64 mm) and fluconazole nano-ZnO (26.76mm), respectively. The lowest and the highest MICs were observed in fluconazole- nano-ZnO and nano-ZnO, respectively. Conclusion: The synergistic effect of Zn nanoparticles with fluconazole can be conducive to the treatment of vaginal candidiasis. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to investigate the association between dietary inflammatory index (DII) and metabolic syndrome (MetS) and its components using data of Ravansar non-communicable diseases (RaNCD) cohort study. Patients and Methods: The present cross-sectional study was performed using the information of 6538 participants in the RaNCD study in Iran. A validated 125-item food frequency questionnaire (FFQ) was used to acquire DII scores. MetS was defined based on national cholesterol education program-adult treatment panel III (NCEP-ATP III) criteria. The association between DII and MetS and its components was investigated by the logistic regression model using STATA software. Results: A significant association was found between DII and MetS (OR trend: 1.08, 95% CI: 1.01– 1.15, P =0.017), triglyceride (TG) (OR trend: 1.06, 95% CI: 1.00– 1.12, P=0.030), fasting blood glucose (FBG) (OR trend: 1.10, 95% CI: 1.01– 1.20, P=0.018) and high density lipoprotein cholesterol (HDL-C) (OR trend: 1.07, 95% CI: 1.02– 1.12, P= 0.005) after adjustment for all covariates. Also, there was a significant relationship between DII score and waist circumference (WC) (OR trend: 1.07, 95% CI: 1.01– 1.14, P=0.016). Conclusion: Higher DII score (a pro-inflammatory diet) had a significant association with the risk of MetS and its components, even after adjustment for different potential confounding factors including socio-demographic data and lifestyle habits. However, further longitudinal investigations with more dietary parameters are needed to elucidate the role of the pro-inflammatory diet in the etiology of MetS. [ABSTRACT FROM AUTHOR]

Background: Carbapenem-resistant Pseudomonas aeruginosa has emerged as a serious problem in many hospitals and intensive care units. The purpose of this study was to determine the antibiotic susceptibility profile and the distribution of metallo-betalactamase genes among P. aeruginosa isolates from Qom province of Iran. Methods: In this study, 200 P. aeruginosa isolates were collected from several clinical samples in hospitals affiliated to Qom University of Medical Sciences, Qomprovince, Iran. The antibiotic susceptibility of the isolates was tested by the Kirby-Bauer disc diffusion test and the distribution of MBL genes among carbapenem-resistant isolates was determined by polymerase chain reaction (PCR) method. Results: Among carbapenem non-susceptible isolates of P. aeruginosa, 38% (76 isolates) were multidrug resistant, 26% (52 isolates) were pan-drug-resistantand5% (10 isolates) were extensive drug resistant. 52% of the isolates were resistant to carbapenems. Among carbapenem non-susceptible isolates of P. aeruginosa, 40 isolates (38.4%) exhibited MBL production. Of 40 MBL-producing isolates, 38 isolates (36.5%) contained the blaIMP gene and two (1.9%) isolates contained the blaVIM gene. Conclusions: Outbreaks of MBL-producing P. aeruginosa isolates will be a serious problem in hospitals in the future and rapid identification of these isolates is necessary to control further dissemination of MBL resistance genes. This is the first report of the rates of MDR, XDR, PDR, and MBL-producing P. aeruginosa isolated from hospitals affiliated toQomUniversity of Medical Sciences inQom province of Iran. [ABSTRACT FROM AUTHOR]

Objective(s): Antibiotic resistance in Acinetobacter baumannii and outbreaks caused by this organism have been reported from several areas of the world. The present study aimed at determining the antibiotic susceptibility profiles and the distribution of OXA-type beta-lactamases among Iranian Acinetobacter baumannii isolates from Qom of Iran. Materials and Methods: For this study, 108 non-duplicate A. baumannii isolates were obtained from clinical specimens in four teaching hospitals in Qom in the central of Iran. The antimicrobial susceptibility of isolates was tested by standard disk diffusion and prevalence of bla OXA genes was investigated by PCR method. Results: Among 97 carbapenem non-susceptible isolates of A. baumannii, 90.72% (88 isolates) isolates showed extensive drug resistance to multiple antibiotics. Among carbapenem resistant isolates, 100% carried blaOXA-51-like, 82.47% carried blaOXA-23-like, 55.67% carried blaOXA-58-like, 22.68% carried blaOXA-40-like and 14.43% had blaOXA-143-like resistance genes. Conclusion: This study demonstrated high genetic diversity of OXA genes among isolates of A. baumannii in Qom, Iran. [ABSTRACT FROM AUTHOR]

Forward osmosis (FO) has gained attention recently due to its low cost and energy consumption while it happens naturally. However, finding a proper draw agent for this process is a challenging task. Magnetic nanoparticles, especially with modified surfaces, have been reported as a promising draw agent, which can be easily recovered by using a magnetic field. Here, an attempt was made to study the effect of different superparamagnetic iron oxide nanoparticles (SPIONs) surface engineering on the osmotic pressure, hydrophilicity, degree of agglomeration of nanoparticles and also water flux. In this study, the osmotic potential of naked Fe3O4, silica-coated superparamagnetic iron oxide nanoparticles (SPION@SiO2), hyperbranched polyglycerol/carboxylate-functionalized SPION (SPION@SiO2@HPG and SPION@SiO2@HPG-CO2H) were evaluated for FO process. The effect of ionized SPIONs on the water flux has been studied for the first time, too. The SPIONs were characterized by scanning electron microscopy, transmission electron microscopy, X-ray powder diffraction, Fourier transform infrared, vibrating sample magnetometer and thermogravimetric analysis. The average of water flux in a long-term performance of FO for the introduced draw agents increased in the order of SPION < SPION@SiO2 < SPION@SiO2@HPG2@HPG-CO2H due to higher hydrophilicity and lesser agglomerations and precipitation. It was surprisingly observed that water flux of ionic magnetic draw solution behaves differently comparing with the non-ionic ones. It was revealed that ionic SPIONs at high concentration led to the formation of non-ideal polyelectrolyte solution that produces a high osmotic pressure. However, by the permeation of water, a transition from non-ideal to ideal solution at some point was observed during FO process. [ABSTRACT FROM AUTHOR]

Objective(s): Helicobacter pylori infection occurs worldwide, but the prevalence of this infection varies greatly among different countries and population groups. The aim of this study was to determine the seroprevalence of anti-Helicobacter pylori and anti-cytotoxin-associated gene A (CagA) antibodies in asymptomatic healthy population in the center of Iran and to investigate the relation with different parameters. Materials and Methods: Totally, 525 individuals aged 17-60 years were enrolled in study. The serum samples of participants were tested for anti-H. pylori IgG and anti-CagA IgG by enzymelinked immunosorbent method (ELISA). ABO blood grouping was also done by hemagglutination test. Results: The seroprevalence of anti-H. pylori IgG was 74.2% and their rates increased with age. The seroprevalence of anti-H. pylori IgG was higher in males (74.6%) than in females (71.6%). There was statistically inverse association between H. pylori infection and education level (P=0.04) and marital status (P=0.000). The most prevalent blood group was type AB with positive Rhphenotype (82.4%). In H. pylori infected individuals the seroprevalence of anti-CagA antibody was 46.9%. The seroprevalence of anti-CagA IgG was in males 48.6% and in females 31.6%. There was no statistically significant association between anti-CagA IgG positivity and age, occupation, socioeconomic status, ABO blood groups and Rh status. Conclusion: These results showed that H. pylori infection was common in the asymptomatic individuals. Almost half of the infected individuals acquire CagA-positive strains of H. pylori. Moreover, it seems that males are more susceptible to infection with CagA-positive strains compared to females. [ABSTRACT FROM AUTHOR]

n expression cassette containing kringle 2 and serine protease domains (K2S), tissue plasminogen activator (tPA), together with a signal sequence derived from Leishmania tarentolae and two fragments of the small subunit ribosomal RNA locus, was introduced into L. tarentolae. The transfected cells produced recombinant K2S (rK2S) protein extracellularly with serine protease activity. Expression and enzyme activity of rK2S in the supernatant was 930 i.u./ml. The specific activity of purified rK2S was 7.4 U/mg of protein. Replacement of the human signal sequence tPA with the signal sequence derived from Leishmania increased the secretion of recombinant protein up to 30 times. [ABSTRACT FROM AUTHOR]

Tuberculosis (TB) is one of the most common zoonotic infectious diseases in the world. Identification of Mycobacterium isolates is essential for proper treatment of TB. The aim of this study was to identify Mycobacterium isolates collected from TB patients in Alborz Province, Iran, by region of differentiation (RD)-typing. Fifty samples from tuberculosis patients were cultured in pyruvate and glycerinated Lowenstein–Jensen medium. DNA was extracted from the isolates by the van Solingen method and subjected to polymerase chain reaction (PCR)-16SrRNA, PCR-IS6110, and RD-typing with primers RD1, RD4, RD9, and RD12, respectively. Out of 50 isolates, only one isolate appeared negative in IS6110-PCR and was considered nontuberculosis complex. The remaining isolates gave PCR products of approximately 543 bp, 245 bp, 146 bp, 172 bp, 235 bp, and 369 bp with 16s-rRNA, IS6110-PCR, RD-1, RD-4, RD-9, and RD-12 PCR, respectively. PCR-restriction fragment length polymorphism of oxyR pseudogene confirmed the results. All isolates except one from Alborz Province appeared positive for Mycobacterium tuberculosis . Based on the obtained results, all isolates except one were identified as M. tuberculosis . The only negative isolate appeared 93% and 97% similar to Nocardia or Mycobacterium sp. ( Mycobacterium neoaurum ), respectively, based on sequencing and alignment of 16s-rRNA and hsp65. Accurate identification of Mycobacterium isolates is of utmost importance for proper and immediate treatment of TB patients. In this study, RD-typing appeared to be a suitable method for correct identification of M. tuberculosis isolates. [ABSTRACT FROM AUTHOR]

Objective/Background Mycobacterium tuberculosis , the etiologic agent of tuberculosis, causes large-scale morbidity and mortality, particularly in developing countries. In recent years, there has been a significant increase in the drug-resistant ability of M. tuberculosis , triggering a major public health crisis. A detailed analysis of the evolution of the mycobacterial genome helps to better understand the genotype–phenotype relationship in this bacterium. Different strain typing methods have already revealed the worldwide diversity of mycobacterial isolates. Therefore, DNA-fingerprinting tools have been developed to improve tuberculosis case detection and control. Molecular typing techniques allow to detect and follow the spread of individual strains of the M. tuberculosis complex (MTC), complementing conventional epidemiological methods. Among these techniques, restriction fragment length polymorphism (RFLP) has been considered the standard method for genotyping of MTC. The aim of this work was to isolate M. tuberculosis from rodents in cattle farms contaminated with MTC located in the city of Booin-Zahra, Iran. Methods A total of 100 samples were collected from the rodents in the contaminated farms and analyzed for the presence of Mycobacterium by growing the samples on Lowenstein–Jensen medium. All isolates were further identified by RFLP and DNA hybridization studies. Results As much as five samples showed the presence of Mycobacterium and these were subjected to PCR-16SrRNA, PCR-IS6110, and RD Typing (RD1, RD4, RD9, and RD12) methods. Further differentiation was performed with Pvu II digestion (RFLP) and DNA hybridization using the polymorphic guanine/cytosine-rich repetitive sequences (PGRS) probe. The PGRS probe results classified two of the isolates as belonging to one cluster, whereas the remaining isolates were classified as belonging to different clusters. An analysis of the obtained genetic pattern and a comparison of these patterns with the genetic pattern of other infected farms allowed us to record the similarities and difference. The results indicated the transmission of Mycobacterium from infected rodents to the cows located in the same farm. Conclusion These results highlight the possible danger of transmission of Mycobacterium among animals. [ABSTRACT FROM AUTHOR]