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Background: The alarming rise of resistant microorganisms is becoming a serious health threat today. Consequently, there is a pressing need to obtain novel compounds with antimicrobial properties. In this regard, lichens are promising substances with antimicrobial potential to control different microbial strains, including fungi, Gram-positive and Gram-negative bacteria, and viruses. Objectives: This study explored the efficacy of Dermatocarpon miniatum in treating burn wound infections. We examined twenty-four Methicillin-resistant Staphylococcus aureus (MRSA) isolated from patients admitted to Imam Moussa Kazem Hospital of Isfahan, Iran.Methods: In this interventional study, we assessed the antibacterial activity of D. miniatum against MRSA using the microdilution broth method. Biofilm inhibitory was evaluated through microtiter plate technique. Additionally, the effect of D. miniatum on the icaA gene expression was analyzed by real-time PCR. Results: The methanolic extract of D. miniatum exhibited significant antibacterial activity against MRSA strains. Additionally, at a concentration of ½ MIC, the extract demonstrated a 65% inhibition of biofilm formation. Moreover, a sub-MIC concentration (1/4) of D. miniatum was effective in reducing the expression of the icaA gene.Conclusion: The results of the present study reveal that D. miniatum extract can be used as a promising antibacterial agent against MRSA strains commonly found in wound biofilms.

Abstract Gastroenteritis infection is a major public health concern worldwide, especially in developing countries due to the high annual mortality rate. The antimicrobial and antibiofilm activity of human mesenchymal stem cell-derived conditioned medium (hMSCsCM) encapsulated in chitosan nanoparticles (ChNPs) was studied in vitro and in vivo against common gastroenteritis bacteria. The synthesized ChNPs were characterized using Zeta potential, scanning electron microscopy (SEM), and dynamic light scattering (DLS) techniques. HMSC-derived conditioned medium incorporated into chitosan NPs (hMSCsCM-ChNPs) composite was fabricated by chitosan nanoparticles loaded with BM-MSCs (positive for CD73 and CD44 markers). The antimicrobial and antibiofilm activity of composite was investigated against four common gastroenteritis bacteria (Campylobacter jejuni ATCC29428, Salmonella enteritidis ATCC13076, Shigella dysenteriae PTCC1188, and E. coli ATCC25922) in-vitro and in-vivo. Majority of ChNPs (96%) had an average particle size of 329 nm with zeta potential 7.08 mV. The SEM images confirmed the synthesis of spherical shape for ChNPs and a near-spherical shape for hMSCsCM-ChNPs. Entrapment efficiency of hMSCsCM-ChNPs was 75%. Kinetic profiling revealed that the release rate of mesenchymal stem cells was reduced following the pH reduction. The antibacterial activity of hMSCsCM-ChNPs was significantly greater than that of hMSCsCM and ChNPs at dilutions of 1:2 to 1:8 (P 106 CFU/ml to approximately (102 to 10) after 72 h. Both in vitro and in vivo assays demonstrated the antimicrobial and antibiofilm activities of ChNPs at a concentration of 0.1% and hMSCsCM at a concentration of 1000 μg/ml to be inferior to that of hMSCsCM-ChNPs (1000 μg/ml + 0.1%) composite. These results indicated the existence of a synergistic effect between ChNPs and hMSCsCM. The designed composite exhibited notable antibiofilm and antibacterial activities, demonstrating optimal release in simulated intestinal lumen conditions. The utilization of this composite is proposed as a novel treatment approach to combat gastroenteritis bacteria in the context of more challenging infections.

Abstract The objective of this study was to synthesize a novel antibacterial and anticancer nanoformulation using aloe vera-derived carbon quantum dots (Cdot) and chromium-doped alumina nanoparticles (Al2O3:Cr/Cdot NPs) via a sol–gel method. X-ray diffraction (XRD) analysis confirmed crystalline NPs with a size range of 10–12 nm, while energy-dispersive X-ray spectroscopy (EDS) revealed their elemental composition without impurities. Fourier-transform infrared spectroscopy (FT-IR) indicated strong interactions between Cdot and Al2O3:Cr NPs, forming a robust heterostructure. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images provided visual confirmation of monodisperse, spherical NPs, ensuring uniformity for further applications. Evaluation of reactive oxygen species (ROS) demonstrated superior generation of singlet oxygen and hydroxyl radicals by Al2O3:Cr/Cdot NPs, essential for photodynamic therapy. Minimum inhibitory concentration (MIC) tests revealed potent antibacterial activity against drug-resistant bacteria, inhibiting biofilm formation by 89% and 95% for MRSA and P. aeruginosa PAO1, respectively. Furthermore, the anticancer activity of Al2O3:Cr/Cdot NPs was assessed using C26 cells, demonstrating enhanced cytotoxicity upon UVA exposure. The NPs exhibited an inhibitory concentration (IC50) of 20 μg/mL without UVA exposure, decreasing to 10 μg/mL with UVA exposure, highlighting the synergistic effect of UVA light in enhancing cytotoxicity. Overall, these findings underscore the significant potential of Al2O3:Cr/Cdot NPs as multifunctional agents for addressing drug-resistant bacteria and advancing cancer therapy, offering promising avenues for nanomedicine research and development.

Background: Mycobacterium tuberculosis affects the lungs in 85% of all cases and the remaining 15% through extra pulmonary affecting other parts of the body such as lymph nodes, pleura, and the genitourinary system. This study aimed to investigate extra-pulmonary tuberculosis (TB) associated factors, failure of treatment, and trends between 2004-2017 in Kashan, Iran. Materials and Methods: This study was conducted during 2004-2017 on newly registered extrapulmonary tuberculosis patients referred to TB Referral Center in Isfahan province, Kashan city, Iran. Information (demographic characteristics, related factors of the disease, and treatment status) of 197 extrapulmonary tuberculosis (EPTB) patients was extracted from Medical case records. Results: In total, 527 cases of Tuberculosis were reported, of which, 159 (30.17%) were confirmed extrapulmonary TB. Eighty-five (53.5%) and 74 (46.5%) were male and female, respectively. Also, 74 (46.5%), and 84 (53.5%) of EPTB were from Iran, and Afghanistan immigrants, respectively. The average age of patients was 41.9±2.18. Among underlying diseases in extrapulmonary TB positive, diabetes mellitus (DM) was predominant with a prevalence of 31 (19.5%), while, 128 (80.5%) cases did not show any underlying disease. Most of the patients were in the age group (21-40 years) with a frequency of 60 (37.7%), and the lowest of patients belonged to the age group (>80 years) with a frequency of 9 (5.7%). No correlation was found between related factors and infection with EPTB (p> 0.05). Conclusion: Our findings showed that the prevalence of EPTB in Kashan was relatively high, but, a relative decrease was shown during 2004-2017, which with preventative measures can be reduced the prevalence.

The emergence, spread, and persistence of multidrug-resistant (MDR) bacteria have become a public health threat. Therefore, it is urgent to investigate novel antimicrobial materials without antibacterial resistance. In this regard, Copper/graphitic carbon nitride nanocomposites (Cu/g-C3N4 NCs) with different loading amounts of Cu nanoparticles (NPs) have been successfully prepared via the co-precipitation-sonication approach. The purity of the nanostructures was verified by the X-ray diffraction (XRD) pattern. The antibacterial activity of Cu/g-C3N4 NCs versus tested bacteria were determined by the microdilution technique. Inhibition of biofilm formation was also evaluated using the microtiter plate method. In addition, the ability of Cu/g-C3N4 NCs to the expression level of the icaA gene was assessed by the Real-Time PCR technique. Our results showed that the doping of graphitic carbon nitride with Cu-NPs can improve the antibacterial activity of g-C3N4. So, sample 4 (Cu:g-C3N4 1;1), with higher Cu content, had the highest antibacterial activity toward tested bacteria. The result also showed that sample 4 recorded the largest inhibition zone diameters against tested bacteria, including Staphylococcus aureus (29 mm) and Pseudomonas aeruginosa (16 mm). In addition, Cu/g-C3N4 NCs exhibited a 65% reduction in biofilm formation for Staphylococcus aureus. Moreover, icaA gene was down-regulated after treatment with Cu/g-C3N4 NCs. In conclusion, our study showed that extract Cu/g-C3N4 NCs can use as a promising anti-biofilm agent against biofilm–producing bacteria.

Objective(s): Klebsiella pneumoniae is the common cause of pneumonia in hospitalized patients, particularly in intensive care units (ICU). The infection can transfer by medical equipment such as mechanical ventilators. This study aimed to investigate the molecular typing of the extended-spectrum beta-lactamase-producing K. pneumoniae isolates recovered from Beheshti Hospital, Kashan, Iran. Materials and Methods: K. pneumoniae isolates producing ESBLs have been collected from the samples obtained from Shahid Beheshti hospital, Kashan, Iran. Antimicrobial susceptibility was determined using the Kirby Bauer disk diffusion method. The presence of ESBLs was evaluated using CLSI for ESBL screening by the double-disk diffusion method. Molecular typing was conducted by pulsed-field gel electrophoresis (PFGE). In total, 89 K. pneumoniae isolates were recovered, of which 47.1% were ESBL producers.Results: Results showed that all of the clinical and environmental isolates were resistant to ceftriaxone, meropenem, cefazolin, cefotaxime, cephalothin, and piperacillin-tazobactam. All isolates were grouped under four clusters (A-D). The major cluster was related to the C cluster with 22 isolates (19 clinical and 3 environmental). Seventy-two percent of isolates were from the ICU ward. There was no correlation between antibiotic resistance patterns and PFGE clusters (P=0.2).Conclusion: We observed a common molecular signature among both clinical and environmental K. pneumoniae isolates, indicating a similar genotype and likely a common origin for ESBL producer isolates found in different hospital wards. Therefore, hospitals need to implement an effective infection control system to decrease the spreading of ESBL strains within the hospitals and subsequently the transmission of the infection to patients.

Bacterial contamination of medical devices is a great concern for public health and an increasing risk for hospital-acquired infections. The ongoing increase in antibiotic-resistant bacterial strains highlights the urgent need to find new effective alternatives to antibiotics. Hyaluronic acid (HA) is a valuable polymer in biomedical applications, partly due to its bactericidal effects on different platforms such as contact lenses, cleaning solutions, wound dressings, cosmetic formulations, etc. Because the pure form of HA is rapidly hydrolyzed, nanotechnology-based approaches have been investigated to improve its clinical utility. Moreover, a combination of HA with other bactericidal molecules could improve the antibacterial effects on drug-resistant bacterial strains, and improve the management of hard-to-heal wound infections. This review summarizes the structure, production, and properties of HA, and its various platforms as a carrier in drug delivery. Herein, we discuss recent works on numerous types of HA-based nanoparticles to overcome the limitations of traditional antibiotics in the treatment of bacterial infections. Advances in the fabrication of controlled release of antimicrobial agents from HA-based nanosystems can allow the complete eradication of pathogenic microorganisms.

Antibiotic resistant microorganisms have become an enormous global challenge, and are predicted to cause hundreds of millions of deaths. Therefore, the search for novel/alternative antimicrobial agents is a grand global challenge. Cellulose is an abundant biopolymer with the advantages of low cost, biodegradability, and biocompatibility. With the recent growth of nanotechnology and nanomedicine, numerous researchers have investigated nanofibril cellulose to try to develop an anti-bacterial biomaterial. However, nanofibril cellulose has no inherent antibacterial activity, and therefore cannot be used on its own. To empower cellulose with anti-bacterial properties, new efficient nanomaterials have been designed based on cellulose-based nanofibrils as potential wound dressings, food packaging, and for other antibacterial applications. In this review we summarize reports concerning the therapeutic potential of cellulose-based nanofibrils against various bacterial infections

Background & Objective: Lichens are the result of the symbiosis of fungi and algae or a cyanobacterium. Various biological activities of some lichen and their components such as: antifungal, anti-bacterial, anti-tumor, anti-inflammatory, antiprotozoal substances are known. In the present study, antifungal activity of methanolic extract of Protoparmeliopsis muralis against Aspergillus flavus is investigated on rats. Materials & Methods: 500 g of Protoparmeliopsis muralis was collected from KaneGonbad mountains in Ilam province, the methanol extract was prepared by soxhle. In order to determine the antifungal activity in in vivo conditions, a wound was created and infected with Aspergillus flavus. Having infected the wound, the researchers divided the rats into 4 subgroups: negative control group, treated with Kotrimoksazol, %5 ointment extract methanolic P. muralis, and with %10 ointment extract methanolic P. muralis. Treatment continued until complete healing of the wound. Finally, the percentage of wound healing was calculated. Results: The result of the present study demonstrated that methanolic extract of P. muralis decreased the area of wound in the treatment group compared to the control group. Conclusion: The antifungal and antioxidant activity of the extract of Protoparmeliopsis muralis accelerated the wound healing process.

Introduction: Daily increasing of bacteria resistance (specially Staphylococcus aureus) to various antibiotics in particular penicillin and methicillin has always led the scientists to look for new medicines. Materials and methods: 600 g of Fulgensia fulgens was collected from KaneGonbad mountains in Ilam province, the methanol extract was prepared by soxhle. In vitro antimicrobial activity of the extract against two gram-positive bacteria (S. aureus and Entrococcus faecalis) and two gram-negative bacteria (Pseudomonas aeruginosa and Escherchia coli) was tested by the use of disc diffusion method and microdilution (with determination of MIC and MBC). Wound was made on the dorsal surface of therat and wound infections caused by S.aureus for determination of in vivo antibacterial effect. Than rats were randomly divided into three groups; control, treated with tetracycline ointment and treated with 10% ointment of F. fulgens extract. Finally, wound areas wear measured on days 3, 5, 7, 9 and 11. Results: Average inhibitory zone diameter of methanolic F. fulgens extract against S. aureus ranged between 11.21 mm to 33.01 mm. According to the wound area on 11th day, it could be concluded that there was a statistically significant difference between the control group (0.63 cm2) and two treatment groups (0) (p

Introduction: Lichens are symbiotic associations of a fungus with green alga or cyanobacteria. Their secondary metabolites are produced by the mycobiont, and accumulate as extracellular tiny crystals on the outer surfaces of the hyphae. Th metabolites have unique biological activities such as antimicrobial, antifungal, antiviral, antiprotozoal, anti-proliferative, anti-tumor, antioxidant, and anti-inflammatory. Materials and methods: Protoparmeliopsis muralis was collected from KaneGonbad mountains in Ilam province and identified by using chemical tests and survey of the anatomical characters. Then TLC and HPLC were carried. The excision wound (5cm long and 2mm deep) was created on skin. Then wounds were infected with Staphylococcus aureus by sterile swab . Rats were randomly placed into three groups: 1- control group, 2- treated group with 5 percent ointment of methanolic extract of P. muralis , and 3- treated group with 10 percent ointment of the extract . Finally an amount of wound healing were measured on days 1, 3, 5, 7, 9 and 11 . Results: By using Thin layers Chromatography and High Performance Liquid Chromatography, the existence of psoromic acid, usnic acid, zeorin and fumarprotocetraric acids were confirmed. The result of the present study demonstrated that methanolic extract P. muralis considerably decreased the area of wound in the treatment group to the control group. Discussion and conclusion: Usnic acid is the major compound in the thallus, it seems that this substance is responsible for special anti-microbial effects and wound healing of this species. Methanolic extract of P. muralis accelerates S. aureus infected wound healing process and decreases the necessary duration of complete wound healing .