Investigation into antibacterial and wound healing properties of platelets lysate against Acinetobacter baumannii and Klebsiella pneumoniae burn wound infections.

BACKGROUND AND AIM: Treatment of burn wound infections has become a global challenge due to the spread of multidrug-resistant bacteria; therefore, the development of new treatment options for the mentioned infections is essential. Platelets have drawn much attention for this purpose because they are a safe and cost-effective source of different antimicrobial peptides and growth factors. The present study evaluated antibacterial effects and wound healing properties of Platelet-derived Biomaterial (PdB) against Acinetobacter baumannii and Klebsiella pneumoniae burn wound infections. METHODS: PdB was prepared through the freezing and thawing process and then, in vitro antibacterial effect was determined by disk diffusion and broth microdilution methods. Afterward, burn wound was inflicted on 56 rats, infected with both bacteria, and topical administration was performed to evaluate antibacterial effects and wound healing properties of PdB. RESULTS: In vitro results showed that PdB inhibited the growth of A. baumannii in the highest dose (0.5), while we did not detect any inhibitory effects against K. pneumoniae. By contrast, PdB significantly inhibited the growth of bacteria in treated animal wounds compared to the control groups (P value < 0.05). Macroscopic assessments pointed to the significant enhancement of wound closure in the treated animals. In addition, histopathological examination demonstrated that treatment of rats with PdB led to a considerable increase in re-epithelialization and attenuated the formation of granulation tissue (P value < 0.05). CONCLUSION: The use of topical PdB is an attractive strategy for treating A. baumannii and K. pneumoniae burn wound infections because it inhibits bacterial growth and promotes wound healing properties.

Comparison of three interventional approaches to prevent ventilator-associated pneumonia in intensive care units (ICUs): A clinical trial study.

BACKGROUND: Ventilator-associated pneumonia (VAP) is an infectious pulmonary disease that develops after 48 hours of ventilation. To date, several methods have been proposed to reduce VAP occurrence, such as the VAP prevention bundle, which involves raising the head of the bed, reducing sedation, avoiding deep vein thrombosis, and preventing peptic ulcer in the gastrointestinal system. The purpose of this study was to evaluate the role of personnel in hand washing, case airway suctioning, and systematic monitoring in the prevention of VAP. METHODS: In the current clinical trial, 129 patients hospitalized and intubated at Vali-e-Asr Hospital ICU in Arak, Iran, were included in the study and randomized to one of the three VAP prevention methods: group A, VAP prevention bundle measures; group B, group A measures plus washing of patients' mouth with 0.12% chlorhexidine and suction of secretion every six hours; and finally group C, group B measures plus 72-hour suction package. Demographic information, VAP diagnosis, and outcome of each patient were recorded in the special checklist. RESULTS: The age of the patients ranged from 18 years to 93 years with a mean of 54.6 ± 21.8 years. There was no significant difference in age, sex, Clinical Pulmonary Infection Score (CPIS), and Glasgow Coma Scale (GCS) between the three groups. However, there is a significant relationship between chest X-ray (CXR) index and pneumonia in the three groups (p < 0.05). The prevalence of pneumonia is generally seen to be higher in patients who were local, diffuse, or patchy than those who had no infiltration (p < 0.05). CONCLUSION: This study showed that the application of VAP prevention bundle measures, mouthwash with chlorhexidine, personnel hand washing, airway suctioning, and systematic monitoring is an efficient approach to the prevention of VAP in ICUs.

Investigation of a novel bilayered PCL/PVA electrospun nanofiber incorporated Chitosan-LL37 and Chitosan-VEGF nanoparticles as an advanced antibacterial cell growth-promoting wound dressing.

Chronic wounds have become a growing concern as they can have a profound impact on individuals, potentially resulting in mortality. It is crucial to prevent and manage bacterial infections, particularly drug-resistant ones. Antimicrobial peptides, such as LL-37, can firmly eliminate pathogens. Additionally, the process of angiogenesis, facilitated by growth factors like VEGF, is essential for tissue repair and wound healing. To enhance the stability and bioavailability of therapeutic agents, targeted delivery strategies utilizing Chitosan-based carriers have been employed. Electrospun biopolymers in advanced wound dressings have revolutionized wound care by providing a more effective and efficient solution for promoting tissue regeneration and speeding up the healing process. The present investigation utilized Chitosan nanoparticles to encapsulate the recombinant LL37 peptide and VEGF. An in-depth investigation was carried out to analyze the biophysical and morphological traits of the LL37-CSNPs and VEGF-CSNPs. The first support layer consisted of PCL electrospun nanofiber, followed by the electrospinning of PVA/CsLL37, PVA/CsVEGF, and PVA/CsLL37/CsVEGF onto the PCL layer. An in vitro examination assessed the fabricated nanofibers' morphological, mechanical, and biological characteristics. The antimicrobial effects were tested on methicillin-resistant Staphylococcus aureus (MRSA). The in vivo experiments assessed the antibacterial and wound-healing capabilities of the nanofibers. The findings validated the continuous release of LL37 and VEGF. The composite material PCL/PVA/CsLL37/CsVEGF demonstrated potent bactericidal and antioxidant characteristics. The cytotoxic assay demonstrated the biocompatibility of the fabricated nano mats and their potential to accelerate fibroblast cell proliferation. The efficacy of PVA/CsLL37/CsVEGF in promoting wound healing was confirmed through an in vivo wound healing assay. Furthermore, the histological analysis provided evidence of faster epidermal formation and improved antibacterial activity in wounds covered with PVA/CsLL37/CsVEGF. Adding LL37 and VEGF to the composite material improves the immune response and promotes blood vessel formation, accelerating wound healing and decreasing inflammation.

PLGA-Based Nanoplatforms in Drug Delivery for Inhibition and Destruction of Microbial Biofilm.

The biofilm community of microorganisms has been identified as the dominant mode of microbial growth in nature and a common characteristic of different microorganisms such as Pseudomonas aeruginosa, Staphylococcus aureus, and Staphylococcus epidermidis. The biofilm structure helps in the protection from environmental threats including host immune system and antimicrobial agents. Thus, the biofilm community has led to a higher prevalence of multidrug-resistant (MDR) strains in recent years. In this regard, the use of a new class of antibiotics, natural compounds, and anti-biofilm enzymes has been considered for the destruction of the microbial biofilm. However, different drawbacks such as low penetration, high susceptibility to degradation, instability, and poor solubility in aqueous solutions limit the use of anti-biofilm agents (ABAs) in a clinical setting. As such, recent studies have been using poly lactic-co-glycolic acid (PLGA)-based nanoplatforms (PLGA NPFs) for delivery of ABAs that have reported promising results. These particles, due to proper drug loading and release kinetics, could suppress microbial attachment, colonization, and biofilm formation for a long time. Additionally, PLGA NPFs, because of the high drug-loading efficiencies, hydrophilic surface, negative charge, and electrostatic interaction, lead to effective penetration of antibiotics to the deeper layer of the biofilm, thereby eliminating the microbial biofilm. Thus, PLGA NPFs could be considered as a potential candidate for coating catheters and other medical material surfaces for inhibition and destruction of the microbial biofilm. However, the exact interaction of PLGA NPFs and the microbial biofilm should be evaluated in animal studies. Additionally, a future goal will be to develop PLGA formulations as systems that can be used for the treatment of the MDR microbial biofilm, since the exact interactions of PLGA NPFs and these biofilm structures are not elucidated. In the present review article, we have discussed various aspects of PLGA usage for inhibition and destruction of the microbial biofilm along with different methods and procedures that have been used for improving PLGA NPF efficacy against the microbial biofilm.

Wound healing performance of PCL/chitosan based electrospun nanofiber electrosprayed with curcumin loaded chitosan nanoparticles.

In this study, the electrospun poly(ε-caprolactone) (PCL)/Chitosan (CS)/curcumin (CUR) nanofiber was fabricated successfully with curcumin loaded chitosan nano-encapsulated particles (CURCSNPs). The morphology of the produced CURCSNPs, PCL, PCL/CS, PCL/CS/CUR, and PCL/CS/CUR electrosprayed with CURCSNPs were analyzed by scanning electron microscopy (SEM). The physicochemical properties and biological characteristics of fabricated nanofibers such as antibacterial, antioxidant, cell viability, and in vivo wound healing efficiency and histological assay were tested. The electrospraying of CURCSNPs on surface PCL/CS/CUR nanofiber resulted in the enhanced antibacterial, antioxidant, cell proliferation efficiencies and higher swelling and water vapor transition rates. In vivo examination and Histological analysis showed PCL/CS/CUR electrosprayed with CURCSNPs led to significant improvement of complete well-organized wound healing process in MRSA infected wounds. These results suggest that the application of PCL/CS/CUR electrosprayed with CURCSNPs as a wound dressing significantly facilitates wound healing with notable antibacterial, antioxidant, and cell proliferation properties.

Wound healing properties and antimicrobial activity of platelet-derived biomaterials.

We analyzed the potential antibacterial effects of two different PdB against methicillin-resistant S. aureus and P. aeruginosa. The third-degree burn wound healing effects of PdB was also studied. Blood samples were obtained from 10 healthy volunteers and biological assays of the PdB were performed and the antimicrobial activity against MRSA and P. aeruginosa was determined using disk diffusion (DD), broth microdilution (BMD), and time-kill assay methods. 48 Wistar albino rats were burned and infected with MRSA. Two groups were injected PdB, the control groups were treated with plasma and received no treatment respectively. In the next step, the rats were euthanized and skin biopsies were collected and histopathologic changes were examined. The results of DD and BMD showed that both PdB performed very well on MRSA, whereas P. aeruginosa was only inhibited by F-PdB and was less susceptible than MRSA to PdBs. The time-kill assay also showed that F-PdB has an antibacterial effect at 4 hours for two strains. Histopathological studies showed that the treated groups had less inflammatory cells and necrotic tissues. Our data suggest that PdB may possess a clinical utility as a novel topical antimicrobial and wound healing agent for infected burn wounds.

Comparing the Effect of Echinacea and Chlorhexidine Mouthwash on the Microbial Flora of Intubated Patients Admitted to the Intensive Care Unit.

BACKGROUND: Providing intubated patients admitted to the intensive care units with oral healthcare is one of the main tasks of nurses in order to prevent Ventilator-Associated Pneumonia (VAP). This study aimed at comparing the effects of two mouthwash solutions (echinacea and chlorhexidine) on the oral microbial flora of patients hospitalized in the intensive care units. MATERIALS AND METHODS: In this clinical trial, 70 patients aged between18 and 65 years undergoing tracheal intubation through the mouth in three hospitals in Arak, were selected using simple random sampling and were randomly divided into two groups: the intervention group and the control group. The oral health checklist was used to collect the data (before and after the intervention). The samples were obtained from the orally intubated patients and were then cultured in selective media. Afterwards, the aerobic microbial growth was investigated in all culture media. The data were analyzed using SPSS software. RESULTS: The microbial flora in the echinacea group significantly decreased after the intervention (p < 0.0001) and it was also the case withmicrobial flora of the patients in the chlorhexidine group (p < 0.001). After 4 days, the oral microbial flora of the patients in the intervention group was lower than that of the patients in the control group (p < 0.001). CONCLUSIONS: The results showed that the echinacea solution was more effective in decreasing the oral microbial flora of patients in the intensive care unit. Given the benefits of the components of the herb Echinacea, it can be suggested as a viable alternative to chlorhexidine.