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Background: Preclinical and clinical studies show that local and systemic antitumor efficacy is achievable by in situ vaccination (ISV) using plant virus nanoparticles in which immunostimulatory reagents are directly administered into the tumor rather than systemically. Aim: To investigate a minimally studied plant virus nanoparticle, alfalfa mosaic virus (AMV), for ISV treatment of 4T1, the very aggressive and metastatic murine triple-negative breast cancer model. Materials & methods: AMV nanoparticles were propagated and characterized. Their treatment impact on in vivo tumors were analyzed using determination of inherent immunogenicity, cytokine analysis, western blotting analysis and immunohistochemistry methodologies. Results: AMV used as an ISV significantly slowed down tumor progression and prolonged survival through immune mechanisms (p

Purpose: This study aimed to design gentamicin-conjugated poly (amidoamine) (PAMAM) dendrimers to increase the therapeutic efficiency of gentamicin against Pseudomonas aeruginosa. Methods: Gentamicin-presenting dendrimers were synthesized using MAL-PEG3400-NHS as a redox-sensitive linker to attach gentamicin to the surface of G4 PAMAM dendrimers. The gentamicin molecules were thiolated by using Traut reagent. Then, the functionalized gentamicin molecules were attached to PEGylated PAMAM dendrimers through simple and high selectively maleimide (MAL)-thiol reaction. The structure of gentamicin-conjugated PAMAM dendrimers was characterized and confirmed using nuclear magnetic resonance (NMR), dynamic light scattering (DLS), zeta potential analysis, and transmission electron microscopy (TEM) imaging. The antibacterial properties of the synthesized complex were examined on P. aeruginosa and compared to gentamycin alone. Results: NMR, DLS, zeta potential analysis, and TEM imaging revealed the successful conjugation of gentamicin to PAMAM dendrimers. Data showed the appropriate physicochemical properties of the synthesized nanoparticles. We found a 3-fold increase in the antibacterial properties of gentamicin conjugated to the surface of PAMAM dendrimers compared to non-conjugated gentamicin. Based on data, the anti-biofilm effects of PAMAM-Gentamicin dendrimers increased at least 13 times more than the gentamicin in normal conditions. Conclusion: Data confirmed that PAMAM dendrimer harboring gentamicin could be touted as a novel smart drug delivery system in infectious conditions.

Background Carbapenem-resistant Enterobacteriaceae (CRE) is a major concern leading to morbidity and mortality in the world. CRE often is becoming a cause of therapeutic failure in both hospital and community-acquired infections. Aim This study aimed to investigate the resistance mechanisms of CRE by phenotypic and molecular methods. Materials and methods Sixty CRE (50 Klebsiella pneumoniae, 6 Escherichia coli, and 4 Enterobacter spp.) were isolated from October 2018 to June 2019. Antimicrobial susceptibility testing was carried out using phenotypic methods. The carbapenem resistance mechanisms including efflux pump hyperexpression, AmpC overproduction, carbapenemase genes, and deficiency in OmpK35 and OmpK36 were determined by phenotypic and molecular methods, respectively. Results Sixty CRE (50 Klebsiella pneumoniae, 6 Escherichia coli, and 4 Enterobacter spp.) were isolated from October 2018 to June 2019. Amikacin was found to be the most effective drug against CRE isolates. All isolates were resistant to imipenem and meropenem by the micro-broth dilution. AmpC overproduction was observed in all Enterobacter spp. and three K. pneumoniae isolates. No efflux pump activity was found. Carba NP test and Modified Hodge Test could find carbapenemase in 59 (98%) isolates and 57 (95%) isolates, respectively. The most common carbapenemase gene was bla OXA-48-like (72.8%) followed by bla NDM (50.8%), bla IMP (18.6%), bla VIM (11.8%), and bla KPC (6.7%). The ompK35 and ompK36 genes were not detected in 10 and 7 K. pneumoniae isolates, respectively. Conclusion The amikacin is considered as a very efficient antibiotic for the treatment of CRE isolates in our region. Carbapenemase production and overproduction of AmpC are the main carbapenem resistance mechanisms in CRE isolates. Finally, Carba NP test is a rapid and reliable test for early detection of carbapenemase-producing isolates.

BackgroundRecent studies demonstrated that the speed of synthesis, biocompatibility, and antimicrobial activity of gold (Au) and silver (Ag) metals is enhanced when biosynthesized in nano-sized particles. In the present study, Au NPs and Ag NPs were synthesized via a biological process using aqueous Ginger root extract and characterized by various spectroscopic methods. Methods & ResultsThe NPs were found to be in hexagonal and spherical shapes. The average particle size for Au and Ag NPs was found to be 20 nm and 15 nm, respectively. The dynamic light scattering (DLS) method has shown that the zeta potential values of synthesized NPs were found to be 5.7 mv and 7.11mv, respectively. Gas chromatography-mass spectrometry (GC-MS) analysis of Ginger root extract revealed 25 compounds. The synthesized NPs showed significant activity against Staphylococcus aureus and Escherichia coli in vitro with IC50 and IC90 values for Au and Ag NPs, respectively, noted to be 7.5 and 7.3 µg/ml and 15 and 15.2 µg/ml for both bacterial strains. The protein leakage level was high and morphological changes occurred in bacteria treated with biosynthesized NPs. ConclusionThese results suggest that the biosynthesized metallic NPs show potential for application as antibacterial agents with enhanced activities.

Additional file 2. Supplementary file 2.

Bacterial nanocellulose (BNC) is a type of 3-dimensionally structured polymer gel produced by Acetobacter that has recently attracted increased interest in wound healing concerns. To produce an effective antibacterial wound dressing, researchers investigated the manufacturing and structural features of honey-infused BNC reinforced gelatin/aldehyde-modified Guar gum films (H/BNC/Ge/AD-GG). Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), mechanical characteristics, water solubility, and degradability were all used to assess the produced films. In addition, the influence of honey addition on the produced films' various properties has been examined. Antibacterial activity, better degradation capability, improved mechanical qualities, and excellent cell adhesion and proliferation by NIH-3T3 fibroblast cells were among the outcomes. The cytotoxicity assay in vitro revealed good cytocompatibility. As a result of the findings, the produced H/BNC/Ge/AD-GG films appear to have a high potential for antibacterial wound dressing applications.

Background:In late December 2019, a new infectious respiratory disease (COVID-19) was reported in a number of patients with a history of exposure to the Huanan seafood market in China. The World Health Organization officially announced the COVID-19 pandemic on March 11, 2020. Here, we provided an overview of the epidemiologic, diagnostic and treatment approaches associated with COVID-19.Methods:We reviewed the publications indexed in major biomedical databases by December 20, 2020 or earlier (updated on May 16, 2021). Search keywords included a combination of: COVID-19, Coronavirus disease 2019, SARS-CoV-2, Epidemiology, Prevention, Diagnosis, Vaccine, and Treatment. We also used available information about COVID-19 from valid sources such as WHO.Results and Conclusion:At the time of writing this review, while most of the countries authorized COVID-19 vaccines for emergency use starting December 8, 2020, there is no a definite cure for it. This review synthesizes current knowledge of virology, epidemiology, clinical symptoms, diagnostic approaches, common treatment strategies, novel potential therapeutic options for control and prevention of COVID-19 infection, available vaccines, public health and clinical implications.

Antibiotic resistance is one of the serious health-threatening issues globally, the control of which is indispensable for rapid diagnosis and treatment because of the high prevalence and risks of pathogenicity. Traditional and molecular techniques are relatively expensive, complex, and non-portable, requiring facilities, trained personnel, and high-tech laboratories. Widespread and timely-detection is vital to the better crisis management of rapidly spreading infective diseases, especially in low-tech regions and resource-limited settings. Hence, the need for inexpensive, fast, simple, mobile, and accessible point-of-care (POC) diagnostics is highly demanding. Among different biosensing methods, the isothermal amplification of nucleic acids is favorite due to their simplicity, high sensitivity/specificity, rapidity, and portability, all because they require a constant temperature to work. Isothermal amplification methods are utilized for detecting various targets, including DNA, RNA, cells, proteins, small molecules, ions, and viruses. In this paper, we discuss various platforms, applications, and potentials of isothermal amplification techniques for biosensing of antimicrobial resistance. We also evaluate the potential of these methods, coupled with the novel and rapidly-evolving platforms offered by nanotechnology and microfluidic devices.

A series of sila-organosulfur compounds containing 1,2,3-triazole cores were screened for their cytotoxic activity on human breast cancer cell line MCF-7. Most of the tested compounds exhibited moderate to good activity against the cancer cells. Especially, the compound 4-((2-(trimethylsilyl)ethynylthio)methyl)-1-benzyl-1H-1,2,3-triazole 3a from series of sila-substituted thioalkyne 1,2,3-triazoles (STATs) and the compounds 3-(1-Benzyl-1H-1,2,3-triazol-4-yl)-1-mercapto-1,1-bis(trimethylsilyl)propane-2-thione 4a and 1-Mercapto-1,1-bis(trimethylsilyl)-3-(1-phenethyl-1H-1,2,3-triazol-4-yl)propane-2-thione 4e from series of sila-substituted mercapto-thione 1,2,3-triazoles (SMTTs)exhibited promising cytotoxicity against MCF-7 with IC50 values of 35.17, 32.63 and 30.3 μg/mL, respectively. In addition, the possible mechanisms for inhibition of cell growth and induction of apoptotic cell death were explored by DAPI staining, cell cycle analysis and qRT-PCR. The synthetic compounds were evaluated for their in vitro anti-bacterial activities, and as a result the most prominent effects were observed for 3e and 4e. Especially, 3e was found to be quite active against all the tested strains with the MIC values ranging from 15 to 62 μg/mL, except P. aeruginosa. The results of the time-kill assay suggested that the compound of 3e completely inhibited the growth of both gram-negative bacteria A. baumannii and gram-positive bacteria S. aureus. In addition, SEM analysis confirmed morphostructural damage of the bacteria. Our findings could be applicable for developing dual targeting anti-cancer/anti-bacterial therapeutics. This article is protected by copyright. All rights reserved.

Graphical abstract, Highlights • MERS-CoV, SARS-CoV-1/2 as members of β-CoVs family have many similar pathogenicity. • Frequency of emerging β-CoVs infections reported in males are higher than females. • Sex-hormones and X-chromosome related genes may be the cause of these sex differences. • Immune response of women might protect further against MERS, SARS-CoV1/2 infections. • Sex-based immune-responses may provide new insights for upcoming immunotherapies., Emerging beta-coronaviruses (β-CoVs), including Severe Acute Respiratory Syndrome CoV-1 (SARS-CoV-1), Middle East Respiratory Syndrome-CoV (MERS-CoV), and Severe Acute Respiratory Syndrome CoV-2 (SARS-CoV-2, the cause of COVID19) are responsible for acute respiratory illnesses in human. The epidemiological features of the SARS, MERS, and new COVID-19 have revealed sex-dependent variations in the infection, frequency, treatment, and fatality rates of these syndromes. Females are likely less susceptible to viral infections, perhaps due to their steroid hormone levels, the impact of X-linked genes, and the sex-based immune responses. Although mostly inactive, the X chromosome makes the female's immune system more robust. The extra immune-regulatory genes of the X chromosome are associated with lower levels of viral load and decreased infection rate. Moreover, a higher titer of the antibodies and their longer blood circulation half-life are involved in a more durable immune protection in females. The activation rate of the immune cells and the production of TLR7 and IFN are more prominent in females. Although the bi-allelic expression of the immune regulatory genes can sometimes lead to autoimmune reactions, the higher titer of TLR7 in females is further associated with a stronger anti-viral immune response. Considering these sex-related differences and the similarities between the SARS, MERS, and COVID-19, we will discuss them in immune responses against the β-CoVs-associated syndromes. We aim to provide information on sex-based disease susceptibility and response. A better understanding of the evasion strategies of pathogens and the host immune responses can provide worthful insights into immunotherapy, and vaccine development approaches.

Purpose: Clofarabine, a purine nucleoside analogue and inhibitor of Ribonucleotide Reductase (RR), is used for treatment of leukemia. Clofarabine-induced defect in DNA replication, induces p53 and subsequently P53R2 genes as subunit of RR. clofarabine deregulated P53R2 gene expression leading to the elevated levels of P53R2 which impose resistance to DNA damaging drugs. In this study the apoptotic and cytotoxic effects of clofarabine has been investigated on breast cancer cell line. Methods: Cofarabine cytotoxicity on T47D cells has been studied by MTT assay. T47D cells were exposed to the different concentrations of clofarabine for 24, 48 and 72 hours intervals. Relative expression of P53R2 gene has been studied using real-time PCR. Moreover, after treating with clofarabine the apoptotic and necrotic cells were detected using Annexin V and propodium iodide (PI) reagents by flowcytometry technique. Results: MTT assay results showed that the clofarabine IC50 on T47D cell line were 3 and 2.5µM after 48 and 72 h exposure, respectively. Clofarabine did not show any significant cytotoxic effect after 24 h exposure. The analysis of qRT-PCR showed a significant increase in P53R2 gene expression in treated cells with both 2.5 and 3 μM doses and also, the results of flowcytometry revealed 26.91 and 74.46 percent apoptosis induction in 48 and 72h treatments respectively in comparison to the control groups. Conclusion: Our results showed that apoptotic and cytotoxic effects of clofarabine on T47D cell line were in time and dose dependent manner; therefore it could be considered a new candidate in breast cancer therapy.

The objectives of the study were to isolate and characterize the bacteriocin producing enterococci in 30 enterococcal poultry isolates from north-west of Iran and to determine the prevalence of bacteriocin structural genes among them. Methods: The obtained isolates were assessed for antibacterial action against 6 indicator strains. The PCR method was applied to detect previously identified enterocin genes. Results: Based on our results 4 (13.3%) of the examined poultry enterococcal isolates were considered as potential bacteriocinogenic strains, all of them identified to be Enterococcus faecium via phenotypic and genotypic examinations. At least one of the detected Bac+ isolates had antibacterial activities against Bacillus cereus, Listeria monocytogenes, Enterococcus faecalis and Enterococcus hirea with no activity against Escherichia coli or Staphylococcus aureus. Conclusion: Genes encoding Enterocin A and enterocin LA50A/B are fairly distributed among the studied poultry enterococci.

Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most common organisms isolated from clinical samples, and has been associated with morbidity and mortality among hospitalized patients. The aim of this study was to evaluate the prevalence and antibiotic susceptibility patterns among MRSA and methicillin-sensitive S. aureus (MSSA) isolates collected from four hospitals in Iran.A total of 183 isolates of S. aureus were collected from various clinical specimens of four hospitals in Iran. The isolates were identified by using the conventional biochemical tests. Three methods-oxacillin agar disk diffusion, oxacillin agar screening, and PCR- were applied to determine susceptibility to oxacillin. The conventional disk agar diffusion test was used to evaluate the antibiotic sensitivity of our isolates against 15 antibiotics, according to the guidelines of the Clinical and Laboratory Standards Institute (CLSI).Of 183 isolates, 77 isolates (42.1%) were found to be MRSA, by the PCR method. The highest antibiotic resistance was found to be against penicillin, co-trimoxazole, erythromycin, and tetracycline respectively. All isolates were susceptible to vancomycin, according to the results of disk agar diffusion. Among other antibiotics, teicoplanin (84%) and fusidic acid (80.5%) were more active against MRSA isolates. For the different methods evaluated, the sensitivities and specificities were as follows: for disk agar diffusion (84.9% and 95.9%) and for agar screening test with oxacillin concentrations of 0.6 μg/ml (70.8% and 97.4%), 4 μg/ml (96.1%and 97.2%) and 6 μg/ml (96% and 96.3%), respectively.The results of our study showed that 47% of S. aureus isolates were MRSA. Overall, in this research study, resistance to all test antimicrobial agents in MRSA isolates were higher than that of MSSA isolates. Our results also revealed that 85% of mecA-positive isolates and 15% of mecA-negative isolates were resistant to methicillin; while 96% of mecA-negative isolates were sensitive to methicillin. Meanwhile 4% of mecA-positive isolates were also sensitive to methicillin.

Gene therapy is defined as the direct transfer of genetic material to tissues or cells for the treatment of inherited disorders and acquired diseases. For gene delivery, magnetic nanoparticles (MNPs) are typically combined with a delivery platform to encapsulate the gene, and promote cell uptake. Delivery technologies that have been used with MNPs contain polymeric, viral, as well as non-viral platforms. In this review, we focus on targeted gene delivery using MNPs.

Background: Tetracycline is an antibiotic widely used for the treatment of Helicobacter pylori infection, but its effectiveness is decreasing due to increasing bacterial resistance. The aim of this study was to investigate the occurrence of 16S rRNA mutations associated with resistance or reduced susceptibility to tetracycline ofHelicobacter pylori by real-time PCR (RT-PCR) assays from culture. Materials and Methods: Tetracycline susceptibility and minimal inhibition concentration (MIC) was determined by the Epsilometer test (Etest) method. A LightCycler assay developed to detect these mutations was applied to DNA extracted from culture. The 16S rRNA of these isolates was sequenced and resistance-associated mutations were identified. From 104 isolates of H. pylori examined, 11 showed resistance to tetracycline. Results: LightCycler assay was applied to DNA extracted from 11 tetracycline-susceptible and 11 tetracycline resistance H. pylori isolates. In our study the sequencing of the H. pylori wild types in 16 s rRNA gene were AGA 926-928 with MIC (0.016 to 0.5µg/ml), while the sequencing and MIC for resistant were GGA and AGC, (0.75 to 1.5µg/ml), respectively. Also we found a novel mutation in 2 strains with 84°C as their melting temperatures and exhibition of an A939C mutation. Conclusions: We conclude that real-time PCR is an excellent method for determination of H. pylori tetracycline resistance related mutations that could be used directly on biopsy specimens.

Diagnosis and treatment of lung cancer have been characterized with a variety of challenges. However, with the advancement in magnetic nanoparticle (MNP) technology, many challenges in the diagnosis and treatment of lung cancer are on the decline. The MNPs have led to many break-through in cancer therapy. This paper seeks to establish the role of MNPs in diagnosis and treatment of lung cancer. It proposes that the existing challenges in the diagnosis and treatment of lung cancer can be addressed through application of MNPs in the process.

Nowadays the control of multidrug resistant (MDR) and pandrug resistant (PDR) bacteria has been the subject of extensive research. In this study an effective strategy was developed to destroy bacteria using low-level laser photothermal therapy combined with biocompatible surface-modified AuNPs. First, chitosan, poly(N-isopropylacrylamide)-co-(2-dimethylamino ethyl methacrylate) P(NIPAAM-co-DMAEMA) and poly(lactic-co-glycolic acid) (PLGA) modified AuNPs were synthesized and fully characterized. Afterwards, P. aeruginosa and A. baumannii (Two Gram-negative strains of bacteria) were exposed to different doses of low level NIR laser (810 nm) radiation in the presence or absence of the as-prepared surface-modified AuNPs (in a 1:1 ratio) and the killing efficiency of the radiated laser doses was calculated based on pour-plate colony count for each condition. Chitosan, P(NIPAAM-co-DMAEMA) and PLGA modified AuNPs were synthesized with a core/shell size of 108, 10 and 120 nm, respectively which was confirmed with DLS and TEM studies. Successful polymerization and surface coating of AuNPs was confirmed by FT-IR and 1H NMR. A decreasing trend in the viability of both bacteria was observed along with an increase of the laser dose for all three types of polymer-coated AuNPs. PLGA@AuNPs exhibited the most effective NIR-induced photothermal killing on both bacteria. In other words, 10 J cm-2 and 30 J cm-2 doses were enough to destroy almost all P. aeruginosa, and A. baumannii, respectively. Our study suggests the usefulness of low-level laser in plasmonic photothermal treatment. The suggested strategy, as a new method of anti-bacterial intervention, can be used for the eradication of infections such as wound infections in order to accelerate the healing process. In addition, the offered strategy can be suggested in the treatment of other bio-threats such as cancerous diseases in vivo. Refereed/Peer-reviewed

Recent data indicates an increasing rate of vancomycin resistance in clinical enterococcal isolates worldwide. The nosocomial enterococci are likely to harbor virulence elements that increase their ability to colonize hospitalized patients. The aim of this study was to characterize virulence determinants in vancomycin-resistant enterococci (VRE) obtained from various clinical sources. During the years 2008 to 2010, a total of 48 VRE isolates were obtained from three University teaching hospitals in Northwest, Iran. Initially, phenotypic speciation was done and minimum inhibitory concentrations (MICs) of vancomycin were determined by agar dilution method and E-test. Then, species identification and resistance genotypes along with detection of virulence genes (asa1, esp, gelE, ace and cpd) of the isolates were performed by multiplex PCR. Thirty eight isolates were identified as vancomycin-resistant Enterococcus faecium (VREfm) and ten as E. faecalis (VREfs). Irrespective of the species, vanA gene (89.58%) was dominant and three phenotypically vancomycin susceptible E. faecium isolates carried the vanB gene. Among virulence genes investigated, the esp was found in 27(71%) VREfm strains, but did not in any VREfs. Other virulence determinants were highly detected in VREfs strains. Our data indicate a high prevalence of E. faecium harboring vancomycin resistance with vanA genotype and the two VRE species displayed different virulence genes.

Objectives: Surface attributes of a restoration play an important role in adherence of plaque bacteria. Prophylaxis methods may be involved in modification of or damaging the restoration surface. The aim of the present study was to evaluate the effect of two prophylaxis methods on adherence of Streptococcus mutans to the surface of two restorative materials. Study design: A total of 60 specimens were prepared from each material; a microfilled composite resin (HelioProgress) and a giomer (Beautifil II). For each material, the specimens were randomly divided into three groups (n=20). Group 1: no prophylaxis treatment (control); Group 2: prophylaxis with pumice and rubber cup; Group 3: prophylaxis with air-powder polishing device (APD). The surfaces of selected specimens from each group were evaluated under a scanning electron microscope (SEM), and the surface topography formed by the two prophylaxis methods was determined by atomic force microscopy (AFM). Adherence of Streptococcus mutans to the surface of specimens was determined by the plate counting method following immersion in a bacterial innoculum for 4 hours, rinsing and sonication. Data were analyzed by two-way ANOVA and post hoc Tukey test for multiple comparisons. Statistical significance was set at P

The objective of the present research was to formulate poly(lactide-co-glycolide) nanoparticles loaded with azithromycin with appropriate physicochemical properties and antimicrobial activity. Azithromycin-loaded poly(lactide-co-glycolide) (PLGA) nanoparticles (NPs) were prepared in three different ratios of drug to polymer by nanoprecipitation technique. Antibacterial activity of these nanoparticles was examined against gram-negative intra cellular microorganism Salmonella typhi. The antibacterial effect was investigated using serial dilution technique to achieve the minimum inhibitory concentration (MIC) of nanoparticles. The results showed that physicochemical properties were affected by drug to polymer ratio. The results showed that nanoscale size particles ranging from 212 to 252nm were achieved. Physicochemical properties were affected by drug to polymer ratio. The highest entrapment efficiency (78.5+/-4.2%) was obtained when the ratio of drug to polymer was 1:3. Zeta (zeta) potential of the nanoparticles was fairly negative. The DSC thermograms and X-ray diffraction patterns revealed that the drug in the nanoparticles was in amorphous state. FT-IR spectroscopy demonstrated no detectable interactions between the drug and polymer in molecular level. In vitro release study showed two phases: an initial burst for 4h followed by a very slow release pattern during a period of 24h. The results of antimicrobial activity test showed that the nanoparticles were more effective than pure azithromycin against S. typhi with the nanoparticles showing equal antibacterial effect at 1/8 concentration of the intact drug. In conclusion, the azithromycin nanoparticle preparations showed appropriate physicochemical and improved antimicrobial properties which can be useful for oral administration.

Metal nanoparticles, such as nanoparticles synthesized using gold, have numerous uncommon chemical and physical properties due to the effects of their quantum size and their large surface area, in comparison with other metal atoms or bulk metal. Gold nanoparticles (GNPs), in particular, are very attractive because of their size and shape-dependent properties. Metal nanoparticles have gathered extensive attention due to their uncommon properties and promising applications in photonics, electronics, biochemical sensing, and imaging. This review covers recent advances in the synthesis of GNPs.

Breast cancer is the most commonly diagnosed cancer and the leading cause of cancer death among women worldwide. Herbal medicines have tremendous potential as promising agents for the treatment of cancer. Curcumin is a natural polyphenol which has many anticancer effects. Because of its low aqueous solubility, low bioavailability, and quick degradation and metabolism, curcumin was released using PLGA-PEG nanoparticles. Herein, the efficiency of pure curcumin and curcumin-loaded PLGA-PEG in MCF-7 human breast cancer cell lines was studied. (1)H NMR, FT-IR and SEM demonstrated PLGA-PEG structure and curcumin loaded on nanoparticles. Subsequently, the cytotoxic effects of free curcumin and curcumin-loaded PLGA-PEG were determined via an MTT assay. Our study confirmed that curcumin-loaded PLGA-PEG has more cytotoxic effects on the MCF-7 breast cancer cell line and could be exploited as a potential source for developing novel drugs against breast cancer.

The properties of graphene, carbon sheets that are only one atom wide, have led researchers and companies to consider its synthesis, properties, and the applications in numerous fields. High-quality graphene is physically powerful, light, nearly transparent, and an exceptional conductor of heat and electricity. Its interactions with other materials and with light and its naturally two-dimensional nature produce unique properties, such as the bipolar transistor effect, ballistic transport of charges, and large quantum oscillations. The following review introduces the many potential applications of graphene.

Background: Coagulase-negative staphylococci (CNS) are a common cause of nosocomial infections. In recent years, an increase in the incidence of methicillin-resistant coagulase-negative staphylococci (MRCNS) has led to the severity of the disease. Objectives: The aim of this study was to isolate and identify MRCNS strains by oxacillin disk agar diffusion, oxacillin agar screening, and polymerase chain reaction (PCR) and to evaluate their antibacterial resistance patterns. Patients and Methods: Totally, 122 CNS isolates were collected from the clinical specimens of four hospitals in Iran. Susceptibility testing was performed by disk agar diffusion against 15 antimicrobial agents. Then, disk agar diffusion, agar screening, and PCR were applied to determine susceptibility to oxacillin. Results: Out of the 122 isolates, 92 isolates were found to be MRCNS by PCR. The sensitivities and specificities of disk agar diffusion and agar screening were 89.2% and 69% and 93.8% and 96.3%, respectively. Also, 93 CNS isolates were resistant to Methicillin according to disk agar diffusion. Discussion: Our results indicated that agar screening was superior to oxacillin disk agar diffusion. A comparison between the antibiotic sensitivity patterns of the MRCNS and the Methicillin-Susceptible Coagulase-Negative Staphylococci (MSCNS) showed that the MRCNS were predominantly multiple-drug resistant isolates as the simultaneous resistance rate to 4 or more antibiotics in the MRCNS and MSCNS was 93% and 56%, respectively.

Dendrimers are nano-sized, radially symmetric molecules with well-defined, homogeneous, and monodisperse structure that has a typically symmetric core, an inner shell, and an outer shell. Their three traditional macromolecular architectural classes are broadly recognized to generate rather polydisperse products of different molecular weights. A variety of dendrimers exist, and each has biological properties such as polyvalency, self-assembling, electrostatic interactions, chemical stability, low cytotoxicity, and solubility. These varied characteristics make dendrimers a good choice in the medical field, and this review covers their diverse applications.

An agar well diffusion bioassay method for determination of clarithromycin in human plasma, using Micrococcus Luteus ATCC 9341 as the assay organism, was compared with a selective high-performance liquid chromatographic (HPLC) method with UV detection. Spiked plasma was used to prepare standard and control samples for both methods. The results of the bioassay analyses with spiked plasma samples were concordant by HPLC methods (R2 =0.871, P < 0.001).The Bland-Altman method also showed good agreement between the results of two methods. HPLC demonstrated an improved precision (0.88-19.86% versus 4.51-26.78%) and accuracy (99.27-103.42 % versus 78.52-131.19 %), compared to those of the bioassay method. The range of linearity obtained by both methods (from 62.5 to 3000 ng/ml for HPLC and from 250 to 3000 ng/ml for the bioassay) includes the range of concentrations of clarithromycin which are considered clinically relevant. However, comparison between HPLC and microbiological assays after oral administration of clarithromycin in healthy volunteers indicated significant differences between the two methods in mean plasma concentration–time profiles. The Bland-Altman method revealed no agreement between the two methods, which can be explained by the presence of active metabolites of clarithromycin in plasma.

Background: Currently, there are evidences for the existence of diverse strains of Helicobacter pylori with different levels of virulence. In other way, the most important reason of therapeutic failure is resistance to the antibiotics. Objectives: The aim of this study was to evaluate the relationship between H. pylori drug resistance and the presence of cagA gene. Patients and Methods: Gastric biopsy specimens were cultured for H. pylori isolation. Resistance to antimicrobial agents, including clarithromycin, metronidazole, and amoxicillin were detected by modified disk agar diffusion tests. The cagA gene was detected using PCR, and the results were analyzed by χ2 and Fishers exact tests using SPSS software version 16. Results: A total of 123 H. pylori-positive patients (68 males, 55 females, mean age 35 ± 18 years old) were studied. The rate of resistance to clarithromycin, metronidazole and amoxicillin were 17.07, 78.86 and 27.64%, respectively. In this study, the cagA was detected in 84 of 123 strains (68.3%). The frequency of resistance to clarithromycin, metronidazole and amoxicillin in cagA positive confirmed microorganisms were, 16 (13.01%), 67 (54.47%) and 24 (19.51%), respectively. While the results for cagA negative ones were 5 (4.06%), 30 (24.39%) and 10 (8.13%), respectively. Conclusions: Our results indicated that the overall antibiotic resistance of H. pylori was high, and the relationship between drug resistance and cagA status was not statistically significant. Therefore, different treatment regimens are not recommended for patients with H. pylori- cagA positive infections.

Objective Seroprevalence of H. pylori infection in Iran exceeds 65% of pediatric population. In this study, we intended to find association between the virulence genes (cagA and vacA) and clinical presentations. Methods H. pylori isolates were achieved from the gastric mucosa of children. In each case, the gastric biopsy specimens were cultured and the organisms identified. Detection of different genotypes was carried out by PCR method. Findings A total of 106 biopsy specimens were cultured and 33 H. pylori isolates obtained. Among these 33 H. pylori strains 24 (73%) were cagA-positive. Genotypes of vacA s1m2, s1m1, s2m2, and s2m1 were 45.5%, 30.3%, 21.2%, and 3%, respectively. Most female patients were infected with genotype s1m2. The vacA-m1 strains were significantly more common in patients with nodular gastritis. There were no statistical differences between the vacA and cagA genotypes and clinical outcomes. Conclusion The frequency of cagA genotype was high. In this study, nodular gastritis was a common finding and was rather significantly associated with m1 allele of vacA.