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Aims: Adolescence is one the most precarious periods of life, concerning the drug abuse. The social cost of the drug abuse and injury among adolescents is extraordinary and requires intervention. The theory of planned behavior (TPB) is perhaps the most influential theory for prediction of social and health behaviors including drug abuse. This study aimed at designing and implementing a curriculum based on the TPB for preventing adolescents from drug abuse. Methods and Materials: This quasi-experimental study was conducted in Hamadan, west Iran. We recruited 140 male high school students from randomly selected schools: they were divided into experimental group, n = 70 and control group, n = 70. The experimental group received 20 hours educational program based on the TPB. The control group receives no intervention. Findings: Compared to the control group, experimental group have significantly elevated post test scores for attitude (19.07 vs. 15.28, p < .001), subjective norm (18.08 vs. 16.45, p < .001), perceived behavioral control (51.67 vs. 54.82, p < .001); and their intention to use drug significantly decreased(p = 0.082) Conclusions: The TPB-based educational program may be effective in prevention of substance abuse among adolescents.

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Aims: Drug abuse among college students continues as a major public-health concern. Theory-driven research is necessary to address and find causes. The current research investigates the utility of Theory of Planned Behavior (TPB) in designing and implementing a drug abuse educational prevention program among medical college students. Methods: This quasi-experimental study was conducted among 120 college students in two groups: experimental and control, who were randomly enrolled at the baseline survey. We used a questionnaire, which included three sections of background data (11 questions), knowledge about the side effects of drug abuse questionnaire (16 questions), and TPB-based questionnaire (20 questions). Educational planning was based on active learning with using group discussion, printed leaflet, and audio-visual CD. The participants were followed up after 2-month intervention. Data were analyzed by the SPSS software version 16 using appropriate statistical tests such as stepwise multiple logistic regressions and t-test. Findings: Almost 6.7% of the participants had a history of drug abuse. The three predictors of 1) attitude, 2) subjective norms, and 3) perceived behavioral control accounted for 48 % of the variation in the outcome measure of the intention to drug abuse. There was a significant improvement in average response for knowledge about the side effects of drug abuse and TPB variables among the students who were under intervention (P < 0.05). Conclusions: Designing intervention to reduce positive attitude and subjective norms toward drug abuse among college students could be useful to substance abuse prevention.

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Multidrug resistance in Acinetobacter baumannii is a growing public health concern all over the world. In the current study, the isolation and antimicrobial resistance pattern and detection of blaOXA-51 and lpxC genes by multiplex PCR method was performed.
All the isolates demonstrated high levels of resistance rates to amikacin, ciprofloxacin, meropenem, imipenem, ceftriaxone, gentamicin, and colistin. Screening of two resistance genes by multiplex PCR showed that all the isolates contained blaOXA-51 and lpxC genes. As we previously reported, nosocomial infections caused by A. baumannii isolates are a major cause of morbidity and mortality in our hospital.
 

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Background:  Pseudomonas aeruginosa is one of the main causes of nosocomial infections with a mortality rate up to 40-50%. Resistance to antibiotics is a global challenge in the treatment of infections caused by this bacterium.  The Class A beta-lactamases genes, including bla_SHV, bla_PER, bla_VEB, are the most common causes of resistance in this microorganism. This study was conducted to determine antibiotic resistance pattern and the presence of bla_per, bla_veb, bla_shv and bla_oxa-10 genes in clinical isolates of P. aeruginosa isolated from patients in a hospital in Bandar Abbas.
Materials and Methods:  This cross-sectional study was conducted on 72 P. aeruginosa clinical isolates. Antibiotic susceptibility testing was performed by disk diffusion method according to the clinical Laboratory Standard Institute. MIC (Minimum inhibitory concentration) of ceftazidime was performed by E-Test. Polymerase chain reaction (PCR) was performed to identify bla_shv, bla_veb-1, bla_oxa-10, and bla_per-1 genes.
Results:  Most of the isolates were detected from intensive care unit and urine samples. The highest resistance rate which was observed to sulfamethoxazole and ceftazidime, were 68 (94.44%) and 44 (61.11%), respectively.  27.8% of these isolates were multidrug resistance. Among 44 ceftazidime resistance isolates, 15 isolates (34%) showed MIC ≥32 µg.ml in the E- test. The prevalence rates of genes were 4.16, 12.5, 8.33, and 1.38% for bla_Oxa-10, bla_Shv, bla_Veb-1, and bla_Per-1 genes, respectively.
Conclusion:  The ceftazidime resistance rate and the prevalence rate of resistance genes in the present study were lower than other Iranian studies.  However, isolation of these genes is alarming that excessive use of antibiotics can lead to over expression of resistance genes and bacterial efflux pumps and the emergence of MDR phenotypes.

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Metformin enhances insulin's effect and increases cells’ sensitivity to insulin. In this paper, nanocomposite was designed and used in the metformin release system, which was able to release the required drug in a controlled manner. In this research, nanoparticles of zinc oxide (ZnO) were prepared via the sol-gel method. The experimental design central composite response surface method was applied for the optimization of the nanoparticles based on varied variables such as the weight of zinc acetate (gr) (X ₁) and the volume of triethanolamine (ml) (X₂). The particle size of the optimized nanoparticle was reported to be 28 ± 21.27 nm; zeta potential and PdI were 25.54 ± 1.64 mV, 0.168 ± 0.05 respectively. The chitosan polymer was used to improve environmental compatibility and increase drug release control; finally, metformin was loaded on the optimized nanocomposite. Structural properties were analyzed using scanning electron microscopy (SEM) X-Ray Diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), and Dynamic Light Scattering (DLS). The SEM images showed that the average nanocomposite size was 40 nm. The results of XRD patterns and SEM images were also consistent with each other and the average particle size was the same. Infrared spectrophotometry showed the presence of chitosan used to coat nanoparticles on their surfaces and confirmed the loading of metformin. An in-vitro metformin release from the nanocomposite was conducted in PBS (pH=7.4) and analyzed by a spectrophotometer at 233 nm. Metformin has a high solubility in water, and since it is difficult to prepare a slow release form of high-solubility drugs, the aim of this study was to design a slow-release formulation of metformin with a suitable profile that could control release without explosive release for up to 120 hours.

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Abstract
Research Subject: Breast cancer is one of the most common cancer in the world with the highest mortality rate in women. Chemotherapy is the typical therapy for the cancer. However, it has side effects due to damage to healthy cells. Targeted drug delivery by nano carriers to the cancerous cells reduces the toxic side effects on normal cells. Serum albumin is a widely used drug carrier because of its availability, ease of preparation, and binding ability to various ligands. Attachment of iron oxide nanoparticles to albumin can control their distribution by applying an external magnetic field.
Research Approach: In this study, albumin nanoparticles attached to superparamagnetic iron oxide nanoparticles (SPIONs) were synthesized and loaded with 5-Fluorouracil (5-FU) anticancer drug by using the desolvation technique. The produced nanoparticles were characterized in terms of size, surface charge, and drug entrapment, by dynamic light scattering (DLS) and UV-Vis spectrophotometry. The cytotoxic effects of 5FU-loaded magnetic albumin nanoparticles and free 5FU on MCF7 cells were evaluated with the MTT assay. The internalization of nanoparticles in MCF-7 cells was confirmed by Prussian blue staining. In the end, the effects of nanoparticles on cell cycle and apoptosis were evaluated by flow cytometry using propidium iodide.
Main Results: The mean particle size and zeta potential of 5FU loaded albumin nanoparticles and albumin magnetic nanoparticles were 220 nm, -25.8 mV, and 221 nm, -28 mV respectively. Drug entrapment efficiency and drug loading efficiency were also, 20%, 1%, and 15.8%, and 0.06% for albumin nanoparticles and magnetic albumin nanoparticles in turn. The drug-loaded magnetic albumin nanoparticles showed higher cytotoxicity than the free drug on MCF-7 cells. The flow cytometry cell cycle analysis showed more cytotoxicity of albumin nanoparticles in comparison with other groups. According to these results, it can be said that 5-FU loaded magnetic albumin nanoparticles were more effective and deserve further studies in the cancer treatment.
Keywords: Albumin magnetic nanoparticles, 5-fluorouracil, targeted drug delivery, MCF-7 cell line

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Aim: The objective of this study was to determine the occurrence and antimicrobial resistance pattern of Staphylococcus aureus strains, as one of the important foodborne pathogens, isolated from unpacked ice creams.
Materials & Methods: A total of 122 unpacked ice cream samples were randomly collected from different localities in East Azerbaijan province and transferred to the laboratory using a cool box and screened for the presence of S. aureus strains. Also, the isolates resistance to antibiotics was determined by disk diffusion method.
Findings: In total, 21.3% of the ice creams samples were contaminated with S. aureus strains. Furthermore, antibiotic susceptibility testing revealed that the highest resistance was against penicillin and erythromycin, whereas the highest susceptibility was observed against gentamicin and rifampin. A warning issue was the significant resistance to vancomycin.
Conclusions: The relative high isolation and antimicrobial resistance rates detected in S. aureus strains isolated from unpacked ice creams underline the necessity for applying strict standards at all processing steps by food control agencies and emphasize the need for educational efforts for those personnel involved in products preparation procedures in order to promote food hygiene. It is worth noting that the emergence of resistance to vancomycin, as the last line of treatment for staphylococcal infections, is a worrying global health concern. Moreover, this study highlighted that poor adherence to personal hygiene and health principles during the food products preparation and/or storage could be a potential factor in the spread of pathogenic bacteria and resistance genes in the community.

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 Research subject: Low solubility of pharmaceutical compounds leads to increasing the required drug dosage and their side effects as well as reducing their therapeutic efficiency. Producing pharmaceutical micro/nanoparticles with homogenous morphology and narrow size distribution is one of the confirmed approaches for their solubility enhancement. So, selection and designing an appropriate method for this purpose is one of the most important research fields of pharmaceutical industries. Over the past three decades, supercritical carbon dioxide (sc-CO₂) based methods as a clean and green technologies have been received much attention in various fields of pharmaceutical industries. However, in order to design and development of these methods for producing micro/nanoparticles, determination of the compounds solubility in sc-CO₂ is essential.
Research approach: In this research, well known empirical models (Adachi and Lu, Ch and Madras, Hozahzbr et al., Bian et al., Mendez-Santiago-Teja), as well as the artificial neural network model were applied for prediction the solubility of six anticancer drugs (Aprepitant, 5-Fluorouracil, Imatinib mesylate, Capecitabine, Letrozole, Docetaxel) in sc-CO₂.
 In order to evaluate the accuracy of these models, a comparison was made between the calculated solubility values and the available experimental data, based on several statistical criteria, such as the average absolute relative deviation (AARD%), adjusted correlation coefficient (R_adj) and F-value.
Main results: According to obtained results, Adachi and Lu model with AARD% value of 12.12% and R_adj value of 0.97 provided acceptable results for solubility of mentioned drugs in sc-CO₂. Also, in comparison between empirical and artificial neural network models, the latter one with AARD% value of 1.65% and R_adj value of 0.9960 was appointed as the most appropriate model for correlation of drugs solubility data.

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Aims: The need for new antibacterial drugs is justified because many pathogens are currently resistant to available antibacterial drugs, and this is an alarming threat to the health of future generations. 1, 3, 4‑Oxadiazole has been shown to pose a wide range of antibacterial activity. Some of the marketed drugs also possess this heterocyclic moiety.  
Materials & Methods: The new derivatives of 1, 3, 4-oxadiazole were synthesized using a single-stage, high-yield method. Then, to measure the antibacterial activity of prepared derivatives agar well diffusion method was employed, and the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) were determined at a concentration of 1mg/mL with three replications.
Findings: Compounds 4a, 4d, and 4i exhibited a promising antibacterial activity against Acinetobacter baumannii PTCC1855. Among the three compounds mentioned, compound 4i showed the best performance with IZ=22±0.75 m.m , MIC=500µg/mL and MBC=125µg/mL at a concentration of 1mg/mL.
Conclusion: The new 1, 3, 4‑Oxadiazole derivative (4i) was shown to be a promising compound for pharmaceutical applications, by adding other functional groups to its structure, it is possible to increase the destructive power of the compound.

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Aims: Helicobacter pylori is a bacterium that colonizes the gastric mucosa and is the main cause of gastritis as well as ulcer and gastric cancer. Due to the clinical significance and international increase in H. pylori multidrug resistance, it is necessary to search for new strategies improving eradication rates. Natural compounds have been demonstrated to have antimicrobial effect and the ability to restore the efficacy of conventional drugs. The objective of this work was to evaluate the antimicrobial effect of the hydroalcoholic extract of Curcuma longa L. (Cu) against H. pylori isolates.
Materials & Methods: The minimum bactericidal concentration of the extract was determined by means of the MTT assay; also, the combination and dose reduction indices for levofloxacin (LVX), metronidazole (MET), and rifampicin (RIF) antimicrobial agents were determined by checkerboard format. Interaction analysis was performed using the CompuSyn program.
Findings: About 90% of H. pylori isolates studied (9/10) were sensitive to the hydroalcoholic extract. Synergism was observed in more than 50% of Cu-LVX, Cu-MET, and Cu-RIF combinations. Additionally, for different concentrations of the extract, reduction rates in antimicrobial agents were determined to be between 0.5 and 360 times.
Conclusions: The hydroalcoholic extract of turmeric showed a good potential to be used as an antimicrobial agent in the treatment of H. pylori infection, either alone or in combination with antibiotics used, suggesting the renewal of the effectiveness of conventional antimicrobials in reducing the phenomenon of antimicrobial resistance.

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ta http-equiv=Content-Type content="text/html; charset=utf-8">ta name=ProgId content=Word.Document>ta name=Generator content="Microsoft Word 15">Aims: Antibiotic resistance is recognized as one of the most challenging public health problems in the world. The need for new antibacterial and antifungal drugs is justified because many pathogens are currently resistant to available drugs. Several components of 1, 3, 4‑oxadiazoles have been shown to pose a wide range of antibacterial activities.
Materials & Methods: The new derivatives of 1, 3, 4-oxadiazole were synthesized using a single-stage method. The structure of derivatives was evaluated by IR, H-NMR, C-NMR, and GC-Mass methods. Then to measure the antibacterial and antifungal activities of the prepared derivatives at a concentration of 0.5 mg/mL, agar well diffusion method was employed, and the minimum inhibitory concentration (MIC) and the minimum bactericidal/fungicidal concentration (MBC/MFC) were determined with three replications.
Findings: The study of antibacterial properties of the prepared derivatives showed the highest activity of the compounds 4b-g against Enterococcus faecalis strains, among which the compound 4g with IZ= 55.66 ± 0.5 mm and MIC=31.25 mg/mL had the greatest effect compared to the others. Also, the compound 4f with MIC= 125 mg/mL had a powerful effect against E. faecalis strains. In the case of fungal samples, the highest activity of the compound 4b was with IZ=12.33±0.5 mm against Candida glabrata and with IZ=13.33±0.5 mm against C. krusei strains.
Conclusion: The new 1, 3, 4‑oxadiazole derivatives (4b, 4d, and 4g) with tolyl, dimetylphenyl, and methoxyphenyl groups were shown to be a promising compounds for pharmaceutical applications so that by adding other functional groups to their structure, it is possible to increase the destructive power of these compounds.

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Aims: Recently, overuse and misuse of antibiotics have led to the development of multidrug-resistant bacteria and infectious diseases caused by these organisms, increasing morbidity and mortality rate in patients. Pseudomonas aeruginosa as a common Gram-negative pathogen is predominantly responsible for hospital-acquired infections. In this study, the prevalence of multidrug-resistant (MDR), extensively drug-resistant (XDR), and pandrug-resistant (PDR) P. aeruginosa strains isolated from clinical specimens of patients admitted to a teaching hospital in Gorgan, Iran, was determined.
Materials & Methods: Clinical samples of blood, urine, burn wound, eye, and secretions (pleural fluid, tracheal or bronchial aspirates and sputum) were collected from all hospitalized patients during a three-month period from April to June 2019. Using conventional biochemical methods, P. aeruginosa strains were identified, and the antibiotic resistance pattern was determined by Kirby-Bauer disc diffusion method.
Findings: A total of 40 (25.4%) P. aeruginosa strains were isolated from 377 clinical specimens. Most of the P. aeruginosa strains were isolated from wound (35%) and urine (30%) samples. Most of the P. aeruginosa positive samples were recovered from intensive care unit (32.5%) and burn ward (30%). The highest susceptibility was shown to fosfomycin (100%), and the lowest susceptibility was observed to ceftazidime (87.5%), followed by aztreonam (60%). Based on the results, 52.5 and 20% of the isolates were MDR and XDR, respectively. All of the MDR isolates exhibited susceptibility to colistin. No PDR phenotype was observed.
Conclusion: Continuous monitoring of drug resistant strains among clinical isolates of P. aeruginosa must be done to adopt effective strategies to decrease the threat of antimicrobial resistance.

 

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Background: In recent years, the widespread prevalence of Multidrug-Resistant (MDR) Staphylococcus aureus strains and the increase in the number of Extensively Drug-Resistant (XDR) and Pandrug-Resistant (PDR) phenotypes amongst S. aureus strains have become one of the greatest challenges. This study aimed to determine the incidence of MDR, XDR, and PDR phenotypes in S. aureus strains in a teaching hospital in Gorgan, Golestan province, Iran.
Materials & Methods: Clinical samples of blood, urine, wound, and sputum were collected from all hospitalized patients during April to June 2019. S. aureus strains were identified using conventional biochemical methods, and antibiotic susceptibility assessment was performed by Kirby-Bauer disc diffusion method.
Findings: A total of 73 isolates were identified as S. aureus. The majority of S. aureus isolates were collected from wound specimens (31 out of 73). Most of the isolates were recovered from internal ward (35 out of 73), followed by intensive care unit (ICU) (16 out of 73). The highest susceptibility was observed to glycopeptides category (100%), and the lowest susceptibility was observed to erythromycin (54.7%), followed by cefoxitin (49.3%). Out of the 73 isolates, 32 (43.8%) were found to be methicillin-resistant S. aureus (MRSA) isolates. Among MRSA isolates, 96.8 and 12.5% were MDR and XDR, respectively. All of the MRSA isolates, were susceptible to vancomycin. No PDR phenotype was observed among the isolates as all of them were sensitive to vancomycin (100%).
Conclusion: Based on the obtained results, the highest and lowest antibiotic resistance was observed against erythromycin and vancomycin, respectively, which is consistent with similar studies conducted in the country. Therefore, these antibiotics should not be used in the empirical therapy of S. aureus infections

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Background: This study aimed to determine antibacterial activity of ethanolic extract of Matricaria chamomilla (chamomile) against methicillin-resistant Staphylococcus aureus (MRSA) and multidrug-resistant (MDR) Pseudomonas aeruginosa strains isolated from clinical specimens.
Materials & Methods: The plant samples were collected, and the flowers and leaves were separated and dried completely in the shade. After grinding, extraction was performed using the maceration method. The extracts of both flowers and leaves were dried at 37°C for 24 hrs. About 500 mg of the dried plant extract was dissolved in 10 mL of 5% dimethyl sulfoxide and sterilized by filtration through a 0.45 µm membrane filter. For the antibacterial assay, agar well diffusion and broth microdilution methods were used.
Findings: No inhibitory effect was observed for both extracts against MDR P. aeruginosa isolates in agar well diffusion method. In broth microdilution method, the leaves extract showed inhibitory effect, and its MIC and MBC were determined at 12.5 and 25 mg/mL concentrations, respectively. The flowers extract showed antibacterial activity against most MRSA isolates. The extract of leaves demonstrated inhibitory effect on 7 MRSA isolates. The MIC and MBC of flowers extract were determined at concentrations of 6.25 and 12.5 mg/mL for most MRSA isolates, while MIC and MBC of leaves extract were 12.5 and 25 mg/mL for a few MRSA isolates, respectively.
Conclusion: In this study, the ethanolic extract of chamomile leaves showed antibacterial activity against MDR P. aeruginosa isolates; meanwhile, the flowers extract showed better activity against MRSA isolates.

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Background: Urinary tract infections (UTIs) cause a wide range of infections in individuals; they are common nosocomial infections that have recently become difficult to treat because of the increased emergence of multidrug-resistant bacteria. The present study aimed to determine and compare the minimum inhibitory concentration of gentamicin alone and in combination with cetirizine against Escherichia coli strains isolated from hospitalized patients with UTI.
Materials & Methods: This study was performed on 76 E. coli strains isolated from a total of 103 samples of patients admitted to three hospitals in Gonbad-e Kavus. Kirby Bauer disk diffusion and broth microdilution tests were used to determine antibiotic susceptibility and the minimum inhibitory concentration (MIC) of gentamicin alone and in combination with cetirizine according to CLSI M100-S25 (2015) criteria.
Findings: Evaluation of the minimum inhibitory concentration of gentamicin-cetirizine combination against E. coli isolates showed that none were able to grow at a concentration of 8 µg/mL. The concentration of gentamicin in combination with cetirizine, inhibiting 90% of E. coli isolates (MIC90), was 4 μg/mL, which was 16 times lower than that of gentamicin alone (MIC90= 64 μg/mL) (p=.02).    
Conclusion: Gentamicin in combination with cetirizine was found to be more potent in inhibiting E. coli isolates than gentamicin alone. Therefore, the results of this study could provide a clear perspective for dealing with drug-resistant pathogens.

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Backgrounds: Nowadays, the need for replacement of new drug structures is felt more than ever due to the spread of microbial resistance. S-triazoles are significant five-membered heterocyclic scaffolds due to their wide range of biological activities.
Materials & Methods: A new series of Schiff bases (5a-f) were synthesized by the reaction of 4-amino-S-triazoles (3a-c) with furan and benzaldehyde 4(d-e). Then a novel series of triazole thioglycosides (7a-f) were synthesized by the reaction of Schiff bases (5a-f) and T-O-acetyle-α-D-glucopyranosyle-Br in the presence of potassium carbonate as a weak base in acetone. The structure of the products was confirmed by FT-IR, H-NMR, and C-NMR assays. The antimicrobial properties of the newly synthesized compounds were studied against four bacterial strains, including Bacillus cereus, Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli, and two fungal strains, including Aspergillus niger and Candida albicans.
Findings: The synthesized compounds exhibited better antifungal activity than antibacterial activity, espetially 7d. Among all the compounds, the compound 7d was found to have the highest activity against C. albicans with IZ=18±0.7 mm, MIC=250 mg/mL, and MFC= 250 mg/mL.
Conclusion: The present study results indicated that compounds containing S-triazole had the potential to be used in a wide variety of new antifungal formulations.

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In this study, nano drug delivery system based on graphene oxide and reduced graphene oxide- polyglycerol hybrids were constructed. Functionalization of nano graphene oxide and reduced graphene oxide was accomplished through noncovalent interaction between the π conjugated system of graphene materials and the aromatic segment in the focal point of polyglycerol polymer. Polyglycerol is a hydrophilic and biocompatible polymer that its conjugation with graphene materials was increased the colloidal stability and decreased the nonspecific interaction of graphene materials. Curcumin as an anticancer hydrophobic natural drug with low systemic bioavailability was simply loaded on these nanohybrids via π-π stacking force between the π conjugated systems of graphene materials and curcumin. Result showed that loading capacity of curcumin for reduced graphene oxide hybrid (49%) is higher than graphene oxide hybrid due to restored of π conjugated system in reduced graphene oxide. Anticancer efficiency of these drug hybrids was investigated by MTT assay. Results showed that these drug carriers have sufficient biocompatibility. Also these nano drug delivery systems showed a cytotoxic effect that was comparable to that of free curcumin. The reduced graphene oxide hybrid is preferred for delivery of curcumin due to its higher loading capacity that can provide efficient dose of drug in low level of carrier

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Research subject: The purpose of this research is to prepare three types of biodegradable scaffolds composed of polyglycerin, sebacic acid, and polycaprolactone diol, synthesized with varying molecular weights and polymer concentrations.
Research approach; Polycaprolactone diol (PCL-diol) with different molecular weights was synthesized via ring-opening polymerization. It was then reacted with sebacic acid and glycerol to enhance the hydrophilicity of the resulting polymers. The drug Teriflunomide was loaded into the system, and its release rate was investigated by immersion in a simulated body environment (phosphate buffer, pH = 7.4) using the dialysis bag method.
Main results: FTIR analysis confirmed the presence of ester, ether, and hydroxyl peaks in the structures of all three scaffolds: PGS–PCL-diol 200, PGS–PCL-diol 500, and PGS–PCL-diol 900. The thermal behavior of the scaffolds was characterized using TGA and DSC methods. Results indicated that the PGS–PCL-diol 900 scaffold experienced 15% more weight loss than the other two. The DMTA test showed that the glass transition temperature of PGS–PCL-diol 900 is higher than that of the other scaffolds, and it also demonstrated the highest network density. Degradability analysis revealed that the PGS–PCL-diol 500 scaffold exhibited the highest degradation rate, with 3.9% greater and faster degradation than the other two samples on the second day. SEM images showed that cells effectively penetrated the scaffolds, forming a well-structured three-dimensional network. The MTT test confirmed good cell attachment and scaffold adhesion. In this study, a composite scaffold with a three-dimensional structure was designed and produced in film form. It was cross-linked without any additives, and each analysis was conducted based on variations in polymer chain length and scaffold molecular weight.
 

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Backgrounds: This study aimed to assess the molecular characteristics of methicillin-resistant Staphylococcus aureus (MRSA) strains isolated from community-acquired (CA) and hospital-acquired (HA) infections in Bandar Abbas, southern Iran.
Materials & Methods: This descriptive cross-sectional study was conducted on 110 S. aureus strains isolated from 59 outpatients and 51 inpatients during 2018-2019. Antimicrobial susceptibility testing was performed using disc diffusion method. Epsilometer test was used to measure vancomycin minimum inhibitory concentration (MIC). Cefoxitin disc (30 μg) was used to screen MRSA isolates. The presence of mecA gene was examined by PCR method.  Staphylococcal cassette chromosome mec (SCCmec) types were detected in S. aureus isolates using multiplex-PCR. Chi-square and Fisher's exact tests were used to analyze the results.
Findings: Out of 110 isolates, 45 (40.9%) isolates carried the mecA gene: 20 (39.2%) isolates from inpatients and 25 (42.4%) isolates from outpatients. MRSA isolates showed the highest resistance to azithromycin (69.8%), tetracycline (60.4%), and clindamycin (32.1%), respectively. Vancomycin MIC against MRSA isolates ranged from 0.75 to 5 μg/mL. SCCmec type I, III, IV, and V were detected in 20 (44.4%), three (6.7%), 16 (35.5%), and six (13.3%) isolates, respectively.
Conclusion: The predominant SCCmec types were type I and type IV, which were detected in CA- and HA-MRSA isolates, respectively. No significant difference in the presence of SCCmec type III and antibiotic resistance was found between CA- and HA-MRSA isolates, indicating the possibility of cross-infection between these isolates. Developing appropriate treatment protocols to prevent the spread of MRSA infections in the community is currently an urgent need.