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This work aimed to select a safe and bacteriocin-producing isolate of Lactobacillus to use it as a probiotic for treating Pseudomonas aeruginosa associated with burn infections. For this purpose, 151 burn wound swabs were collected from patients to isolate the most common multi-drug resistance Pseudomonas aeruginosa that could be used as an indicator. In addition, thirty-six Lactobacillus isolates were collected from different sources and subjected to a screening program to evaluate their antagonism activities against MDR P. aeruginosa. Based on results, the isolate Lactobacillus HLB12 showed a highest bacteriocin production which was further characterized as Limosilactobacillus fermentum through 16s ribosomal RNA. Several tests were performed to study the properties of Limosilactobacillus fermentum HLB12, particularly its biosafety and suitability to be a successful probiotic. Results showed that L. fermentum HLB12 was resistant to β-lactams group such as ticarcillin/clavulanate. Whereas it was sensitive to amikacin, ciprofloxacin and levofloxacin. Moreover, the results confirmed that L. fermentum HLB12 was safe as a probiotic without any health impacts as it has no hemolytic activity. Furthermore, results revealed that this bacterium was strongly adherent and good biofilm producer, had high autoaggregation capability and high ability of adhering with Pseudomonas aeruginosa. Limosilactobacillus fermentum cells were successfully incorporated into a gel base formula. The results revealed that cells kept their viability over 21 days with an ability to produce and release the bacteriocin. The formula was tested in vitro and results showed a high antagonistic activity against Pseudomonas aeruginosa. Next, the formula was tested in vivo to treat rabbit models with full-thickness skin burn. Upon examining the healing process, results showed signs of remodeling stage by day four and scar tissue formation by day nine. The results supported the idea of using probiotic as an alternative method for the treatment with antibiotics. [ABSTRACT FROM AUTHOR]

Normal skin is the first line of defense in the human body. A burn injury makes the skin susceptible to bacterial infection, thereby delaying wound healing and ultimately leading to sepsis. The chances of biofilm formation are high in burn wounds due to the presence of avascular necrotic tissue. The most common pathogen to cause burn infection and biofilm is Pseudomonas aeruginosa. The purpose of this study was to create a microemulsion (ME) formulation for topical application to treat bacterial burn infection. In the present study, tea tree oil was used as the oil phase, Tween 80 and transcutol were used as surfactants, and water served as the aqueous phase. Pseudo ternary phase diagrams were used to determine the design space. The ranges of components as suggested by the design were chosen, optimization of the microemulsion was performed, and in vitro drug release was assessed. Based on the characterization studies performed, it was found that the microemulsion were formulated properly, and the particle size obtained was within the desired microemulsion range of 10 to 300 nm. The I release study showed that the microemulsion followed an immediate release profile. The formulation was further tested based on its ability to inhibit biofilm formation and bacterial growth. The prepared microemulsion was capable of inhibiting biofilm formation. [ABSTRACT FROM AUTHOR]

Mucormycosis is an uncommon infection but is increasing in prevalence. Cutaneous disease is associated with burns and traumatic injuries. Cutaneous mucormycosis is the least deadly form but mortality is still approximately 36%. Burn superinfection with mucormycosis is increasingly common and can be an insidious process that may not present until the disease disseminates. We present the case of a 30-year-old male who presented to the emergency department for a rash. A rash with yellow crusting was noted to involve his scalp, face, ear, right shoulder, and parts of both feet. He had been placed on antibiotics by an urgent care a few days prior to presenting. He denied systemic symptoms, chemical exposure, change in detergent, autoimmune diseases, or travel. The patient has a history of intravenous opioid and dissociative abuse and had multiple episodes of syncope—including at his work in a factory where there were hot metals, refrigerants, and numerous corrosive chemicals. Surgical debridement revealed mucormycosis on pathology. The patient was treated with isavuconazole, surgical debridement, and skin grafting. He experienced complete recovery. [ABSTRACT FROM AUTHOR]

Klebsiella pneumoniae is among the most frequent microorganisms isolated from infections of burn wounds. This cross-sectional study aimed to investigate the distribution of multi-drug resistant (MDR) K. pneumoniae in two burn hospitals and the antibiotic resistance profile in different burn regions of the same patient. It was performed in two hospitals (Al-Zahraa and Al-Karama) in Al-Kut, Iraq, between January and May 2022. Totally, 100 burn swabs were collected from 40 patients of both genders suffering from burn wound infections, with ages ranging between 3 and 50 years. Klebsiella pneumoniae were isolated and identified using conventional methods followed by VITEK®2 system and confirmed via polymerase chain reaction targeting the gapA gene. Then, the antimicrobial susceptibility pattern was studied by the VITEK®2 system. Of the 100 burn wound swabs, 20 isolates were K. pneumoniae. Fifty five percent (11 out of 20) of K. pneumoniae isolated in the current study were MDR and 35% of the isolates had the extended spectrum beta-lactamase (ESBL) which is the main antibiotic resistance mechanism. Furthermore, the bacteria isolated from different burned areas of the same patient showed variable pattern of antibiotic susceptibility. To conclude, K. pneumoniae contaminating the burn wards in the Iraqi hospitals are mostly MDR, against which tigecycline is the most effective antibiotic. [ABSTRACT FROM AUTHOR]

Prolonged inflammation and infection in burns may cause inadequate healing. Platelet granules contain anti-inflammatory mediators that impact wound healing. Synthetic platelets (SPs) avoid portability and storage difficulties of natural platelets and can be loaded with bioactive agents. We evaluated wound healing outcomes in deep partial-thickness (DPT) burns treated topically with SP loaded with antibiotics. Thirty DPT burns were created on the dorsum of two Red Duroc hybrid pigs. Six wounds were randomized into five groups: SP alone, SP loaded with gentamicin vesicles, SP with gentamicin mixture, vehicle control (saline), or dry gauze. Wounds were assessed from postburn days 3-90. Primary outcome was re-epithelialization percentage at postburn day 28. Secondary outcomes included wound contraction percentage, superficial blood flow relative to normal skin controls, and bacterial load score. Results showed that re-epithelialization with the standard of care (SOC) was 98%, SP alone measured 100%, SP loaded with gentamicin vesicles was 100%, and SP with gentamicin mixture was 100%. Wound contraction was 5.7% in the SOC and was ∼10% in both the SP loaded with gentamicin vesicles and SP with gentamicin mixture groups. Superficial blood flow in the SOC was 102.5%, SP alone was 170%, the SP loaded was 155%, and gentamicin mixture 162.5%. Bacterial load score in the SOC was 2.2/5.0 and was significantly less at 0.8/5.0 in SP loaded with gentamicin vesicles (P > 0.05). SP and gentamicin mixture scored 2.7 and 2.3/5.0. Topical SP treatment did not significantly improve outcomes. However, SP loaded with gentamicin-infused vesicles decreased bacterial load. [ABSTRACT FROM AUTHOR]

One of the most common bacteria in nosocomial and burn infections is Pseudomonas aeruginosa. Due to the high antibiotic resistance of P. aeruginosa and the lack of other effective therapeutic agents, treating diseases caused by this bacterium could be challenging. Therefore, finding novel solutions to control and prevent highly resistant strains of P. aeruginosa is paramount. After isolation and identification of Lactobacilli with known probiotic properties such as L. acidophilus, L. paracasei, L. rhamnosus, and L. bulgaricus using PCR technique, and preparation of their corresponding phage (PAO1 Φ), probiotics and phage were used individually and in combination to treat burn infection caused by P. aeruginosa in a mouse model. The results revealed that the combination of phage with probiotics can be highly effective for treating P. aeruginosa burn infections. Our study showed that the most effective multiple cocktails of Lactobacilli for the treatment of P. aeruginosa infection, were L. rhamnosus + L. bulgaricus + L. paracasei cocktail in mixture with phage (PAO1 Φ). The study proposes an alternative method for the treatment of P. aeruginosa infections. The combination of probiotics with phage could be proposed as a new therapeutic agent for treating P. aeruginosa infections. [ABSTRACT FROM AUTHOR]

Background and Aim: Pseudomonas aeruginosa (P. aeruginosa) is an important causative organism of burn infection. Several virulence factors are implicated in P. aeruginosa colonization and invasion, making P. aeruginosa infection's outcome worse. Type III secretion system (T3SS) effector proteins are among these virulence factors. The present study evaluated the frequency of genes encoding T3SS effectors as a virulence determinant in P. aeruginosa isolates from burn patients. Materials and Methods: Wound swabs were collected from burn patients admitted to the Plastic and Reconstructive Surgery Center, Mansoura University, Egypt, and identified by different microbiological testing methods. The modified Kirby Bauer's disc diffusion method was used to test the antibiotic susceptibility of P. aeruginosa isolates against different antibiotics. Prevalence and the presence of exo genes that encode type T3SS proteins (exoS, exoT, exoU, and exoY) in P. aeruginosa isolates were evaluated by the multiplex PCR. Chi-square and Fisher's test were used for statistical analysis. Results: A total of 45 P. aeruginosa isolates were identified from 101 burn patients, including 27 males and 18 females, with a mean age of 15.78±2.65 years old. P. aeruginosa isolates were mostly susceptible to piperacillin/tazobactam and imipenem (73.33 and 62.22%), respectively; while the lowest susceptibility rates were in ceftazidime (4.44%), Tobramycin (4.44%), and ceftriaxone (6.67%). The exoY and exoT genes were detected in 100% of the P. aeruginosa isolates, while 62.22% and 42.22% of clinical isolates harbored exoS and exoU genes, respectively. Conclusion: This study established a correlation between T3SS proteins, particularly exoS and exoU genes and antimicrobial resistance in P. aeruginosa isolates from burn infection. [ABSTRACT FROM AUTHOR]

Abstract Failure in the treatment of P. aeruginosa, due to its broad spectrum of resistance, has been associated with increased patient mortality. One alternative approach for infection control is quorum quenching which was found to decrease virulence of such pathogen. In this study, the efficiency of a recombinant Ahl-1 lactonase formulated as a hydrogel was investigated to control the infection of multidrug resistant (MDR) P. aeruginosa infected burn using a murine model. The recombinant N-acylhomoserine lactonase (Ahl-1) was formulated as a hydrogel. To test its ability to control the infection of MDR P. aeruginosa, a thermal injury model was used. Survival rate, and systemic spread of the infection were evaluated. Histopathological examination of the animal dorsal skin was also done for monitoring the healing and cellular changes at the site of infection. Survival rate in the treated group was 100% relative to 40% in the control group. A decrease of up to 3 logs of bacterial count in the blood samples of the treated animals relative to the control group and a decrease of up to 4 logs and 2.3 logs of bacteria in lung and liver samples, respectively were observed. Histopathological examination revealed more enhanced healing process in the treated group. Accordingly, by promoting healing of infected MDR P. aeruginosa burn and by reducing systemic spread of the infection as well as decreasing mortality rate, Ahl-1 hydrogel application is a promising strategy that can be used to combat and control P. aeruginosa burn infections.

Vibrio vulnificus is an invasive marine bacterium that causes a variety of serious infectious diseases. With the increasing multidrug-resistant variants, treatment of V. vulnificus infections is becoming more difficult. In this study, we explored antimicrobial blue light (aBL; 405 nm wavelength) for the treatment of V. vulnificus infections. We first assessed the efficacy of aBL against five strains of V. vulnificus in vitro. Next, we identified and quantified intracellular porphyrins in V. vulnificus to provide mechanistic insights. Additionally, we measured intracellular reactive oxygen species (ROS) production and bacterial membrane permeabilization following aBL exposures. Lastly, we conducted a preclinical study to investigate the efficacy and safety of aBL for the prevention and treatment of burn infections caused by V. vulnificus in mice. We found that aBL effectively killed V. vulnificus in vitro in both planktonic and biofilm states, with up to a 5.17- and 4.57-log10 CFU reduction being achieved, respectively, following an aBL exposure of 216 J/cm2. Protoporphyrin IX and coproporphyrins were predominant in all the strains. Additionally, intracellular ROS was significantly increased following aBL exposures (P < 0.01), and there was evidence of aBL-induced permeabilization of the bacterial membrane (P < 0.0001). In the preclinical studies, we found that female mice treated with aBL 30min after bacterial inoculation showed a survival rate of 81%following 7 days of observation, while only 28% survival was observed in untreated female mice (P < 0.001). At 6 h post-inoculation, an 86% survival was achieved in aBL-treated female mice (P = 0.0002). For male mice, 86 and 63% survival rates were achieved when aBL treatment was given 30min and 6 h after bacterial inoculation, respectively, compared to 32%survival in the untreatedmice (P = 0.0004 and P = 0.04). aBL did not reduce cellular proliferation or induce apoptosis. We found five cytokines were significantly upregulated in the males after aBL treatment, including MCSF (P < 0.001), MCP-5 (P < 0.01), TNF RII (P < 0.01), CXCL1 (P < 0.01), and TIMP-1 (P < 0.05), and one in the females (TIMP-1; P < 0.05), suggesting that aBL may induce certain inflammatory processes. In conclusion, aBL may potentially be applied to prevent and treat V. vulnificus infections. [ABSTRACT FROM AUTHOR]

Vibrio vulnificus is an invasive marine bacterium that causes a variety of serious infectious diseases. With the increasing multidrug-resistant variants, treatment of V. vulnificus infections is becoming more difficult. In this study, we explored antimicrobial blue light (aBL; 405 nm wavelength) for the treatment of V. vulnificus infections. We first assessed the efficacy of aBL against five strains of V. vulnificus in vitro. Next, we identified and quantified intracellular porphyrins in V. vulnificus to provide mechanistic insights. Additionally, we measured intracellular reactive oxygen species (ROS) production and bacterial membrane permeabilization following aBL exposures. Lastly, we conducted a preclinical study to investigate the efficacy and safety of aBL for the prevention and treatment of burn infections caused by V. vulnificus in mice. We found that aBL effectively killed V. vulnificus in vitro in both planktonic and biofilm states, with up to a 5.17- and 4.57-log10 CFU reduction being achieved, respectively, following an aBL exposure of 216 J/cm2. Protoporphyrin IX and coproporphyrins were predominant in all the strains. Additionally, intracellular ROS was significantly increased following aBL exposures (P < 0.01), and there was evidence of aBL-induced permeabilization of the bacterial membrane (P < 0.0001). In the preclinical studies, we found that female mice treated with aBL 30 min after bacterial inoculation showed a survival rate of 81% following 7 days of observation, while only 28% survival was observed in untreated female mice (P < 0.001). At 6 h post-inoculation, an 86% survival was achieved in aBL-treated female mice (P = 0.0002). For male mice, 86 and 63% survival rates were achieved when aBL treatment was given 30 min and 6 h after bacterial inoculation, respectively, compared to 32% survival in the untreated mice (P = 0.0004 and P = 0.04). aBL did not reduce cellular proliferation or induce apoptosis. We found five cytokines were significantly upregulated in the males after aBL treatment, including MCSF (P < 0.001), MCP-5 (P < 0.01), TNF RII (P < 0.01), CXCL1 (P < 0.01), and TIMP-1 (P < 0.05), and one in the females (TIMP-1; P < 0.05), suggesting that aBL may induce certain inflammatory processes. In conclusion, aBL may potentially be applied to prevent and treat V. vulnificus infections.

In this study, 225 isolates of Pseudomonas aeruginosa were recovered from burn wounds in major hospitals in Duhok and Erbil, Iraq, between April 2015 and September 2015. A total of 136 of these isolates were from men, comprising 60.4% of the total, whereas 89 (39.6%) were recovered from women. One hundred of these isolates were selected (50 from each province of Erbil and Duhok) and subjected to 16 different antibiotics using the disc diffusion method. The isolates showed a high level of resistance to most of the tested antibiotics, with 90% of the isolates being multidrug resistant. Imipenem was considered as the most effective antibiotic against these isolates with a resistant rate of 47%. The genome of all of these isolates were successfully amplified and produced a single band for the 16S rDNA locus with a molecular weight of about 956 base pairs, which was used to confirm, at the molecular level, that all these isolates were indeed P. aeruginosa. The results of the detection of five virulence-related genes including opr1, toxA, exoS, lasB, and nan1 revealed that 10 of these isolates, accounting for 10%, lacked any of the tested virulence markers. The opr1 gene, as a marker for the presence of a pathogenicity island, was the most dominant marker among all the virulence markers and was detected in 90 isolates (90%), followed by the toxA and exoS genes, which were both observed in 86 (86%) isolates, whereas the lasB gene was found in 82 (82%) isolates and the nan1 gene in 35 (35%) of the isolates, respectively.

Background: The nanotechnology considers as one of the most promising technologies in the treatment of diseases and the manufacture of drugs with high efficiency. This review highlighted on the designing of nanoparticles (NPs) for therapeutics. The size of nanoparticle important in reaching to the target and get out from the body by kidney. Nanostructured and nanocrystalline nanomaterials are the two basic types of nanomaterials. The safe of nanoparticle is one of the most attractive attribute of nanoparticle when it will chose as a medicine. Dendrimers are extensively employed in therapeutic implementation because of their structural attribution of this component. Moreover, the capsid protein of virus is extremely natural nanoparticles can be used in medicine. Nanogels can be used for biological sensors, and other biological applications and administration of pharmaceuticals. Beside that there are many nanoparticles that have many medical applications, i.e. nanodiamonds (NDs), metallic NPs, quantum dots (QDs), Silica-Based NPs (SBNPs), Lipid-Based Nanoparticles (Liposomes). Conclusion: One of the most important applications of NPs, which was highlighted in this review, is the use of nanoparticles in the treatment of microbial contaminated burns. Finally, it can be concluded that the using of NPs and nanomaterials with no cytotoxic effect in medication are considered one of the most important technologies that have emerged in recent years.

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Hossein Rahimi,1 Shahla Roudbarmohammadi,1 Hamid Delavari H,2 Maryam Roudbary31Department of Medical Mycology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran; 2Department of Materials Engineering, Faculty of Engineering, Tarbiat Modares University, Tehran, Iran; 3Department of Medical Mycology and Parasitology, School of Medicine, Iran University of Medical Sciences, Tehran, IranBackground: Candida albicans as an opportunistic fungus is one of the most important causes of late-onset morbidity and mortality in patients with major burns and severely impaired immune system. In recent years, the emergence of resistance to opportunistic fungi and toxicity of antimicrobial drugs make it necessary to develop new drugs.Methods: In the present study, we investigated anticandidal effects of indolicidin, as a representative of host defense peptide, conjugated with gold nanoparticles in fluconazole-resistant clinical isolates of C. albicans. After characterizing the conjugation of indolicidin using biophysical methodologies, the cytotoxicity and hemolytic activity of the nanocomplex were examined. In addition, the expression level of ERG11, responsible for antifungal resistance, and the immunomodulatory effect of peptide-nanomaterial conjugates were assessed.Results: Our data indicated that the nanocomplex was nontoxic for the fibroblast cells and erythrocytes. Treatment with the nanocomplex significantly reduced the expression levels of the ERG11 gene in fluconazole-resistant C. albicans isolates and the iNOS gene in macrophages.Conclusion: The study data provides a chance to develop innovative therapies for the treatment of C. albicans burn infections. However, further investigation is required to examine the efficiency of the nanocomplex.Keywords: burn infection, Candida albicans, indolicidin, gold nanoparticles, antimicrobial peptides

Failure in the treatment of P. aeruginosa, due to its broad spectrum of resistance, has been associated with increased patient mortality. One alternative approach for infection control is quorum quenching which was found to decrease virulence of such pathogen. In this study, the efficiency of a recombinant Ahl-1 lactonase formulated as a hydrogel was investigated to control the infection of multidrug resistant (MDR) P. aeruginosa infected burn using a murine model. The recombinant N-acylhomoserine lactonase (Ahl-1) was formulated as a hydrogel. To test its ability to control the infection of MDR P. aeruginosa, a thermal injury model was used. Survival rate, and systemic spread of the infection were evaluated. Histopathological examination of the animal dorsal skin was also done for monitoring the healing and cellular changes at the site of infection. Survival rate in the treated group was 100% relative to 40% in the control group. A decrease of up to 3 logs of bacterial count in the blood samples of the treated animals relative to the control group and a decrease of up to 4 logs and 2.3 logs of bacteria in lung and liver samples, respectively were observed. Histopathological examination revealed more enhanced healing process in the treated group. Accordingly, by promoting healing of infected MDR P. aeruginosa burn and by reducing systemic spread of the infection as well as decreasing mortality rate, Ahl-1 hydrogel application is a promising strategy that can be used to combat and control P. aeruginosa burn infections. [ABSTRACT FROM AUTHOR]

Infection is the leading cause of complications and deaths after burns. However, the difference in infection patterns between the burn intensive care unit (BICU) and burn common wards (BCW) have not been clearly investigated. The present study aimed to compare the infection profile, antimicrobial resistance, and their changing patterns in burn patients in BICU and BCW. Clinical samples were analyzed between January 1, 2011, and December 31, 2019, in the Institute of Burn Research in Southwest China. The patient information, pathogen distribution, sources, and antimicrobial resistance were retrospectively collected. A total of 3457 and 4219 strains were detected in BICU and BCW, respectively. Wound secretions accounted for 86.6% and 44.9% in BCW and BICU, respectively. Compared with samples in BCW, samples in BICU had more fungi (11.8% vs. 8.1%), more Gram-negative bacteria (60.0% vs. 50.8%), and less Gram-positive bacteria (28.2% vs. 41.1%). Acinetobacter baumannii were the most common pathogen in BICU, compared with Staphylococcus aureus in BCW. S. aureus was the most frequent pathogen in wound secretions and tissues from both BICU and BCW. However, A. baumannii were the first in blood, sputum, and catheter samples from BICU. Overall, the multidrug-resistance (MDR) rate was higher in BICU than in BCW. However, the gap between BICU and BCW gradually shortened from 2011 to 2019. The prevalence of MDR A. baumannii and Klebsiella pneumonia significantly increased, especially in BCW. Furthermore, Carbapenem resistance among K. pneumoniae significantly increased in BICU (4.5% in 2011 vs. 40% in 2019) and BCW (0 in 2011 vs. 40% in 2019). However, the percentage of MDR P. aeruginosa sharply dropped from 85.7% to 24.5% in BICU. The incidence of MRSA was significantly higher in BICU than in BCW (94.2% vs. 71.0%) and stayed at a high level in BICU (89.5% to 96.3%). C. tropicalis and C. albicans were the two most frequent fungi. No resistance to Amphotericin B was detected. Our study shows that the infection profile is different between BICU and BCW, and multidrug resistance is more serious in BICU than BCW. Therefore, different infection-control strategies should be emphasized in different burn populations.

Infection is the leading cause of complications and deaths after burns. However, the difference in infection patterns between the burn intensive care unit (BICU) and burn common wards (BCW) have not been clearly investigated. The present study aimed to compare the infection profile, antimicrobial resistance, and their changing patterns in burn patients in BICU and BCW. Clinical samples were analyzed between January 1, 2011, and December 31, 2019, in the Institute of Burn Research in Southwest China. The patient information, pathogen distribution, sources, and antimicrobial resistance were retrospectively collected. A total of 3457 and 4219 strains were detected in BICU and BCW, respectively. Wound secretions accounted for 86.6% and 44.9% in BCW and BICU, respectively. Compared with samples in BCW, samples in BICU had more fungi (11.8% vs. 8.1%), more Gram-negative bacteria (60.0% vs. 50.8%), and less Gram-positive bacteria (28.2% vs. 41.1%). Acinetobacter baumannii were the most common pathogen in BICU, compared with Staphylococcus aureus in BCW. S. aureus was the most frequent pathogen in wound secretions and tissues from both BICU and BCW. However, A. baumannii were the first in blood, sputum, and catheter samples from BICU. Overall, the multidrug-resistance (MDR) rate was higher in BICU than in BCW. However, the gap between BICU and BCW gradually shortened from 2011 to 2019. The prevalence of MDR A. baumannii and Klebsiella pneumonia significantly increased, especially in BCW. Furthermore, Carbapenem resistance among K. pneumoniae significantly increased in BICU (4.5% in 2011 vs. 40% in 2019) and BCW (0 in 2011 vs. 40% in 2019). However, the percentage of MDR P. aeruginosa sharply dropped from 85.7% to 24.5% in BICU. The incidence of MRSA was significantly higher in BICU than in BCW (94.2% vs. 71.0%) and stayed at a high level in BICU (89.5% to 96.3%). C. tropicalis and C. albicans were the two most frequent fungi. No resistance to Amphotericin B was detected. Our study shows that the infection profile is different between BICU and BCW, and multidrug resistance is more serious in BICU than BCW. Therefore, different infection-control strategies should be emphasized in different burn populations. [ABSTRACT FROM AUTHOR]

Background: Infection is the most common complication and cause of death in patients suffering burn injuries. These patients are susceptible to infection and burn wound sepsis secondary to the alterations in their physiology. Diagnosis and management of infections rely on physical examination, cultures, and the pathology of the burn wound. Method: We performed an electronic search for articles in the Google Scholar and PubMed databases using the search terms "burn sepsis," "burn infection," and "burn critical care." Results: Multiple factors increase burn patients' risk of invasive infection and sepsis, including underlying factors and co-morbidities, the percent total body surface area of the burn, delays in burn wound excision, and microbial virulence/bacterial count. Organisms causing burn wound infection differ, depending on the time since injury and its location; and diagnosis is multi-factorial. The most common pathogens remain Staphylococcus and Pseudomonas spp. Conclusion: Overall, the recognition of burn sepsis is based on clinical findings. Treatment consists of a combination of local dressings, early burn excision, and systemic antimicrobial therapy. The mortality rate has decreased significantly over the past 10 years, but continued efforts at timely management and infection prevention are essential. [ABSTRACT FROM AUTHOR]

Burn injury and wound is a pig problem that assists the pathogens to grow and cause infection. 149 burn injury swabs were taken from different site of the patients’ body ages (11-53 years old). All samples were tested to isolate the sigificant microorganisms that found in burn injury. Antibiotics test was performed by using disc diffusion way that stated by Kirby-Baucer. Results appeared that the most frequent pathogen in burn injury was Pseudomonas aeruginosa 33(22.14%) and followed by E.coli 31(20.8%), Staphylococcus aureus 28(18.79%), Proteus vulgaris 26(17.48%), Coagulase-negative Staphylococci 12(8.05%), Proteus mirabilis 10(6.71%), Klebsiella pneumonia 5(3.35%) and Candida spp. 4(2.68%) respectively. Antibiotic test showed that Staphylococcus aureus was a high resistance against Gentamycin and ciprofloxacin, but it was sensitive to Vancomycin and Imipenem. Coagulase negative Staphylococci showed a resistance to Gentamicin, Ciprofloxacin and Ceftazidime, but it was sensitive to Amikacin, Oxacillin, Cefotaxim, Vancomycin, Imipenem and Cefepime. P. aeruginosa showed resistance against Cefotaxime, Aztreonam, Gentamicin and Ceftazidime. Whlist it showed a high sensitivity against Imipenem, Cefepime and Tobramycin. E.coli showed a high resistance against Ceftriaxone, Ciprofloxacin and Cephalothin. whilst it showed a high sensitivity against Ticarcillin/clavulanic acid, Imipenem, Cefepime and Tobramycin. Proteus vulgaris showed a high resistance against Ceftriaxone, Ceftazidime, Amikacin, Cephalothin and Gentamicin. Whilst it showed a high sensitivity against Cefotaxime, Aztreonam, Ticarcillin/clavulanic acid and Imipenem. Proteus mirabilis showed resistance against Amikacin, Ciprofloxacin, Ceftriaxone, Gentamicin and Cephalothin. Whilst it showed a high sensitivity against Ceftazidime, Cefotaxime, Aztreonam, Ticarcillin/clavulanic acid, Imipenem, Cefepime and Tobramycin. Klebsiella pneumonia showed resistance against Ciprofloxacin, Ceftazidime, Cefotaxime and Aztreonam. whilst it showed a high sensitivity against Ceftriaxone, Amikacin, Gentamicin, Cephalothin, Ticarcillin/clavulanic acid, Imipenem, Cefepime and Tobramycin. The current study was aimed to determine the most frequent pathogens in burn injury and test their antibiotics susceptibility in hospitalize patients in Najaf city. [ABSTRACT FROM AUTHOR]

Background and purpose: Pseudomonas aeruginosa is one of the most important pathogens of burn infections in hospitals. It causes infection by producing some virulence factors such as exoS and exoT cytotoxins. The aim of this study was to evaluate the frequency of exoS and exoT genes among P.aeruginosa isolated from wound infections in burn patients and the relationship between the presences of these genes and antibiotic resistance. Materials and methods: In this descriptive cross-sectional study, the wounds of 80 burned patients in Sari Zare Hospital were sampled during April, May, and June 2016. After identification by biochemical tests, 18 isolates of P.aeruginosa were obtained. Antimicrobial susceptibility to 8 antibiotics was determined by disk diffusion method. PCR was performed for detection of exoS and exoT genes. Data was analyzed in SPSS V21 applying Chi-square. The significance level was considered at P

Bingjie Mai,1,2 Yiru Gao,1,2 Min Li,1,2 Xiaobing Wang,1,2 Kun Zhang,1,2 Quanhong Liu,1,2 Chuanshan Xu,3 Pan Wang1,2 1Key Laboratory of Medicinal Resources and Natural Pharmaceutical Chemistry, Ministry of Education, 2National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest China, College of Life Sciences, Shaanxi Normal University, Xi’an, 3School of Chinese Medicine, Faculty of Medicine, Chinese University of Hong Kong, Hong Kong, China Background and objectives: Antibiotic resistance has emerged as one of the most important determinants of outcome in patients with serious infections, along with the virulence of the underlying pathogen. Photodynamic antimicrobial chemotherapy (PACT) has been proposed as an alternative approach for the inactivation of bacteria. This study aims to evaluate the antibacterial effect of sinoporphyrin sodium (DVDMS)-mediated PACT on Staphylococcus aureus and multidrug resistant S. aureus in vitro and in vivo.Materials and methods: Bacteria were incubated with DVDMS and exposed to treatment with light. After PACT treatment, colony-forming units were counted to estimate the bactericidal effect. Intracellular reactive oxygen-species production was detected by flow cytometry. Flow cytometry and fluorescence-microscopy detection of bacterial cell-membrane permeability. Enzyme-linked immunosorbent assays were used to determine expression of VEGF, TGFβ1, TNFα, IL6, and bFGF factors in burn infection.Results: DVDMS-PACT effectively killed bacterial proliferation. Intracellular ROS levels were enhanced obviously in the PACT-treatment group. SYTO 9 and propidium iodide staining showed a decrease in the ratio of green:red fluorescence intensity in the PACT-treatment group in comparison to the control group. Enzyme-linked immunosorbent-assay results revealed that in the healing process, the expression of bFGF, TGFβ1, and VEGF in the treatment group were higher than in the control group, which inhibited inflammation-factor secretion. In addition, skin-tissue bacteria were reduced after treatment.Conclusion: These results indicate that DVDMS-PACT presents significant bactericidal activity and promotes wound healing after burn infections. Keywords: PACT, antibacterial efficacy, burn infection, MDR

Background: Systemic inflammatory response syndrome (SIRS) can occur as a physiological response without indicating a burn infection. The Centers for Disease Control and Prevention's (CDC's) clinical sepsis criteria for infection screening may not be accurate with burn patients, especially for diagnosing central line-associated bloodstream infections (CLABSIs). New clinical sepsis criteria were therefore proposed by the American Burn Association (ABA) in 2007. Nonetheless, no study has compared the accuracy of the ABA and CDC clinical sepsis criteria for burn-CLABSI diagnoses. Objective: The present study aimed to investigate the relative accuracies of the ABA and CDC clinical sepsis criteria for burn- CLABSI diagnoses, and to report the CLABSI incidence at Siriraj Hospital's Burn Unit. Materials and Methods: A retrospective chart review was conducted of burn patients admitted to the Burn Unit 2007 to 2015. Patients with central venous catheter insertions were included. Details of demographic data; comorbidities; burn type; total burn surface area; and type, duration, and purpose of the central lines were analyzed. The sensitivities and specificities of the ABA and CDC clinical sepsis criteria for CLABSI diagnoses were compared. Results: Of the 101 patients enrolled, CLABSIs were diagnosed in 38 (37.8%). The most common infection site was the internal jugular vein (33%), with CLABSIs occurring most frequently with non-dialysis double lumen catheters. The sensitivity and specificity of the ABA criteria were 76.3% and 93.6%, respectively, with an 85.9% accuracy. Conclusion: The ABA clinical sepsis criteria can be used to diagnose CLABSI in burn patients with acceptable accuracy and a higher specificity than the CDC criteria. [ABSTRACT FROM AUTHOR]

Infection following burn injury is critical, especially for patients with large total body surface area burns and in skin graft donor sites. Although various aspects of a-tocopherol acetate (a-TA) beneficial effects on wound healing have been validated, it appears that no study has specifically addressed its antimicrobial potential. The purpose of this study was to explore the therapeutic efficacy of topical application of a-TA in terms of bacterial load reduction. Between January 2018 and June 2018, 20 patients with mid-deep and deep burn wounds were included in the present study (average TBSA approximately 42%, range 25-67%). Patient average age was 47.75 years (range 25-72 years), 8 were male. In each patient two clinically similar areas were identified and treated every 24 hours with topical application of α-TA in the form of Filme Olio® (Group 1) and conventional medication (Group 2). All the patients had positive results for bacterial cultures before treatment. Despite the presence of initial bacterial infection, a quicker reduction of exudates and pain and a progressive and faster bacterial load reduction was observed in Group 1. Negative cultures were obtained after 3 days on average in Group 1 (range 1-6 days) and 8 days in Group 2 (range 5-9 days). This study clearly shows the importance of the therapeutic targeting of infection in the treatment of burns. α-TA may represent a safe, simple and inexpensive method for improving the healing of difficult wounds with local infection. [ABSTRACT FROM AUTHOR]

Children with burn injuries are prone to increased risk for infection. Pantoea agglomerans is a particularly uncommon microorganism related to burn wound infections. A previously healthy, 28-month-old-boy was admitted with scald due to hot water. His general condition was moderate with normal vital signs. He had full thickness (right anterior forearm, 1.5%) and partial thickness (upper part of left arm, 0.5%; left anterior forearm, 2%; right thigh, 1%; right leg, 0.5%; left thigh, 0.5%; and left leg, 1%) burn wounds with totally estimated surface area percentage of 7%. Laboratory findings (hemogram, C-reactive protein, erythrocyte sedimentation rate, and blood biochemistry) were unremarkable. As well as hemodynamic stabilization and nutritional support, daily dressing with silver sulfadiazine was performed. Ten days later, grafting was carried out as the wound on right anterior forearm did not heal. Prophylactic intravenous cefazolin treatment (50mg/kg/day) was started. Four days after operation, he had 38.8°C fever and wound infection was realized. Gram stain of the swab revealed gram negative rods. Antibiotic treatment changed to ceftriaxone (75 mg/kg/day). While blood culture was negative, swab culture grew Pantoea agglomerans, resistant to cefazolin, sensitive to ceftriaxone. His fever subsided after 24 hours of ceftriaxone treatment and he was discharged on the 10th day. His immunological investigation was normal. One week later on control examination, his lesion was epithelized. Burn wound infections in pediatric age group can be caused by rare organisms. Other than presence of immunodeficiency, a graft tissue may ease this situation. [Med-Science 2016; 5(3.000): 878-83]

Introduction: Burns are one of the most common and devastating forms of trauma. Patients with serious thermal injury require immediate specialized care in order to minimize morbidity and mortality. (1) The main purpose of this study was to determine the prevalence of bacterial wound infection in critically ill burn patients in surgical intensive care unit in Egypt. Objectives: The aim of this study was to determine the bacterial isolates in sever burn wound infection, suitability to antibiotics and there are mortalities. Methods: We conducted a one year retrospective study in the surgical ICU. Wound swab Culture and sensitivity reports of admitted patients. All the patients of all age groups suffering with flame burnt and both sexes having complete Culture and sensitivity reports were included. Results: The main finding of the current study described herein was the percent of isolates from burn wound (60%). The most common organism was pseudomonas (49%). Multidrug resistant gram negative organisms represent about 60% of the isolates. Pattern of antibiotic sensitivity was 84% for colistin, 39% for amikacin and 35% for imipenem. The mortalities in our study were 80%.

Abstract Background and Objectives: Pseudomonas aeruginosa is the most common organism, which is separated from the burn infections. Due to increased antibiotic resistance, there are many problems to deal with the infections caused by Pseudomonas aeruginosa. This study aimed to determine the resistance to antibiotics against clinical isolates of Pseudomonas using phenotype methods. Material and Methods: 100 strains of Pseudomonas aeruginosa were collected from the burn patients in Taleghani hospital in Ahwaz, Iran, during a six-month period. After phenotypically initial identification, antibiotic sensitivity of isolated strains to conventional antibiotics against Pseudomonas aeruginosa was determined using a disk diffusion technique, and Phenotypic screening for MBLs production was performed. Results: the maximum percentage was related to wound infection and the frequencies of the resistance to imipenem, meropenem, piperacillin, piperacillin-tazobactam, ceftazidime, gentamicin, amikacin, and ciprofloxacin, doripenem, ertapenem and colistin sulphate, were 70%, 53%, 83%, 67%, 91%, 88%, 84%, 84%, 33%, 90%, and 0%, respectively. The use of CD Test methods was approved for determining resistance to Carbapenems. Conclusion: antibiotic resistance to Pseudomonas aeruginosa is increasing and colistin sulphate is the most effective antibiotic. Keywords: Pseudomonas Aeruginosa; Burn Infection; Antibiotic Resistance.

The aim of this study was to evaluate the topical bactericidal activity of peptide PV3 against a MDR isolate of Pseudomonas aeruginosa in a mouse model of burn infection. The structural analysis of PV3 by circular dichroism spectroscopy indicated a low peptide helical content in water, whereas a high helical content was observed in the presence of the more hydrophobic 50% (v/v) trifluoroethanol/water buffer. A confocal microscopy analysis indicated that the main action of PV3 occurred at the membrane of bacteria. Peptide PV3 exhibited superior in vitro anti‐Pseudomonas activity and killing kinetics as compared with doripenem. A single dose of the topically applied peptide PV3 (4 × MBC, 120 min) was found to be sufficient to eradicate MDRP. aeruginosa in a bacterially infected mouse burn wound model, whereas doripenem (4 × MBC) failed to eradicate the initial inoculum. This indicates a potent and fast PV3‐associated bactericidal activity, contrary to doripenem. An in‐depth analysis of mouse skin by histopathology revealed that peptide PV3 (4 × MBC) did not induce any topical skin toxicity. Overall, the data strongly suggest that peptide PV3 might be a potent candidate antimicrobial agent active on antibiotic‐resistant isolates of pathogenic bacteria. [ABSTRACT FROM AUTHOR]

In addition to the nature and extent of the thermal injury influencing infections, the type and quantity of microorganisms that colonize the burn wound appear to influence the risk of invasive wound infection. A total of 80 patients with second degree burns were enrolled in this study with a gender ratio of 1.22:1 (44 females and 36 males). They were at both Imam Ali and Al-kindy hospitals in Baghdad. Culturing of the burn areas and antibiotic sensitivity were tested at three different times (48 h, 5th day and 10th day) of the patients entry to the burn units in hospitals to detect the most frequent microorganisms isolated from burn injuries and then determine the antibiotic they are sensitive to. The most frequent microorganisms were Pseudomonas aeruginosa, followed by Klebsiella pneumoniae and then S. aureus, while Acinetobacter baumannii has a clear percentage. Mixed culture have been also found in both survivor and non-survivor, especially P. aeruginosa and K. pneumoniae. A high percentage of resistance was found among clinical isolates in general to the commonly used antibiotics. [ABSTRACT FROM AUTHOR]

Curcumin is an effective wound healing agent in burn therapy, but due to its low bioavailability, it is required to be formulated for topical therapy. Liposomal nanocarriers are developed as stable and efficient dermal delivery systems. In this study, we prepared curcumin-propylene glycol liposomes (Cur-PgL) to treat animals subjected to second degree burns. The characterization tests confirmed the production of monodisperse nanoliposomes of average size of about 145 nm with high entrapment efficiency percentage and a sustained release behavior. TEM analysis of nanocarriers showed no aggregation in long time storage up to 60 days. The biocompatibility of the Cur-PgL formulation was evaluated by ISO standards. We found that Cur-PgL 0.3% was the effective dose in injured rats without any side effects on intact skin. The cytotoxicity of the Cur-PgL 0.3% nanovesicles was also assessed on human dermal fibroblast (HDF) cells. The results showed no detectable cytotoxicity, but considerable cytotoxicity was observed in higher concentration of 1.5 and 3 mg/ml of free and PgL forms of curcumin. Eight days of application of Cur-PgL on burned rats resulted in a significant ( P<0.001) recovery of wound repair parameters, and after 18 days, wound contraction occurred significantly ( P < 0.001) compared to the other groups. The antibacterial activity of the Cur-PgL formulation was found to be similar to the silver sulfadiazine (SSD) cream 1% regarding the inhibition of the bacterial growth. In conclusion, the low dose of curcumin nanoliposomal formulation efficiently improved injuries and infections of burn wounds and it can be considered in burn therapy. [ABSTRACT FROM AUTHOR]

Objective: As the number of commercially available wound dressings is increasing rapidly, it is important for clinicians to understand the strengths and limitations of each and to recognise relationships between wound type and dressing properties to obtain optimal healing results. Our aim is to test the antimicrobial activity of two dressings. Method: A hydroconductive (HC) dressing and a silver-impregnated foam (SIF) dressing were compared for their potential to reduce the levels meticillin-resistant Staphylococcus aureus (MRSA). We also assessed MRSA-derived biologically active components in liquid or agar matrices, simplified models for heavily exuding or dry wounds respectively, and in an in vivo animal model with MRSA infected wounds. Results: In the agar model (dry wounds) both dressings showed a strong reduction in MRSA activities within 24 hours post-application. The antibacterial effects of the SIF dressing were more pronounced in the liquid model, however, at an increasing cytotoxic cost. In agreement with these in vitro results, assessment of dressings using an MRSA-infected wound in an rat model showed a decrease in MRSA which was significant 7 days post-burn and inoculation, with more compromised viability of MRSA. Dressings showed a similar capability to reduced and eliminate toxic shock syndrome toxin (TSST-1) at day 7 post-burn in the animal model but not at day 4, where the SIF dressing was more potent Conclusion: These results confirm the advantages of using silver in reducing bacterial load in wound treatment, except for conditions of highly exuding wounds where the cytotoxic properties of silver may offset these advantages and HC dressing use is more suitable Declaration of interest: This work was funded in part by SteadMed. Medical. [ABSTRACT FROM AUTHOR]

Burn injuries are one of the major global health problems. Despite aggressive local and systemic treatment to minimize infection, severe burn wounds continue to become infected with environmental and nosocomial pathogens at relatively high rates. We developed an ultrasound assisted sol–gel technique to prepare treated cotton fibers by coating fabric surface with NiO/organic polymer/enzyme matrix forin vitroevaluation of antibacterial activity. The surface modification was performed to bond more efficiently NiO nanoparticles using cellulase enzyme, to reduce initial bacterial attachment on the hydrophilic surface using poly(ethylene glycol), and to promote ultrasonic generation and to overcome agglomeration of the nanoparticles, respectively. Disk diffusion method was used to quantify the efficacy of NiO-based cottons againstPseudomonas aeruginosaandStaphylococcus aureusas two most burn wound pathogens isolated from burn wound swabs and tissue biopsies of hospitalized burn patients.Almost bacterial isolates showed high resistance to the commonly used antibiotics for burn infection treatment.In vitroantibacterial evaluation showed that the modified cottons exhibited excellent biocidal action against both high-resistant isolated Gram-positive and Gram-negative bacteria. [ABSTRACT FROM AUTHOR]

Infection is a major cause of mortality and morbidity among burn patients. An effective measure to reduce infection is routine monitoring of bacterial infection and antimicrobial susceptibility patterns at the burn unit. This will help to create a burn centre-specific empirical antibiotic therapy protocol. A retrospective, descriptive study was conducted at the Cipto Mangunkusumo Hospital (RSCM) Burn Unit between September-November 2016. Data regarding bacterial culture isolates, antimicrobial susceptibility spectrum, and the number of burn patients diagnosed with sepsis were collected. There were 36 patients with positive bacterial cultures, with the isolates changing continuously between Klebsiella pneumonia (17%), Pseudomonas Aeruginosa (12%) and Acinetobacter baumannii (11%). High resistance was found for 10 antimicrobials, particularly cephalosporins. The three bacteria were only sensitive to carbapenem, aminoglycosides and tigecycline. Fourteen patients were diagnosed with sepsis (38.9%), 10 died. Two major sepsis-causing bacteria were P. aeruginosa (33.3%) and K. pneumoniae (28.9%). Bacterial isolates in our setting changed every month. Almost all bacterial isolates are multi-drug resistant, highly resistant to the empirical therapy given (ceftriaxone), leading to outbreaks of sepsis and increased mortality rates. Carbapenem (imipenem, meropenem and doripenem) and aminoglycosides (amikacin) combination was the selected empirical therapy. [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa is most common cause of nosocomial infections in burn centers. This opportunistic and multidrug resistant bacterium causes severe problems for hospitalized burn patients. Samples were collected from patients attending Burn& Plastic Surgery Hospital in Duhok / Iraq, between September 2011 and March 2012, for preliminary identification of P. aeroginosa using conventional methods, then confirmed with the use of BD -PhoenixTM Automated Microbiology System. Isolates were considered Multi Drug Resistant Pseudomonas aeroginosa (MDRPa) if they showed resistance to the three or more classes of antipseudomonal agents. Accordingly thirty isolates were found MDRPa. The pattern of resistance revealed that the highest resistance was for Gentamicin 96.7%, Cefepime 96.7%, Ceftazidime 90% and Aztreonam 83.3%,while lowest resistance was detected against Amikacin 36.7% and Colistin 3.3% .The results of disc diffusion assay demonstrated that antibacterial activities of black seed oil acetone extract at 1:1,1:10,1:25 concentrations were found effective against all tested MDRPa isolates, which were statistically significant (P < 0.05),while at highest dilution 1:75 . All MDRPa isolates showed lowest activity of oil extract . The antimicrobial effects of water extract showed lowest and poor activity against all tested bacteria.

Introduction Burns are one of the most common and devastating forms of trauma. Patients with serious thermal injury require immediate specialized care in order to minimize morbidity and mortality. (1) The main purpose of this study was to determine the prevalence of bacterial wound infection in critically ill burn patients in surgical intensive care unit in Egypt. Objectives The aim of this study was to determine the bacterial isolates in sever burn wound infection, suitability to antibiotics and there are mortalities. Methods We conducted a one year retrospective study in the surgical ICU. Wound swab Culture and sensitivity reports of admitted patients. All the patients of all age groups suffering with flame burnt and both sexes having complete Culture and sensitivity reports were included. Results The main finding of the current study described herein was the percent of isolates from burn wound (60%). The most common organism was pseudomonas (49%). Multidrug resistant gram negative organisms represent about 60% of the isolates. Pattern of antibiotic sensitivity was 84% for colistin, 39% for amikacin and 35% for imipenem. The mortalities in our study were 80%. [ABSTRACT FROM AUTHOR]

Burn wound infection is the leading cause of mortality among burn wound patients. One of the most commonly isolated bacterial burn wound pathogens is Pseudomonas aeruginosa , a notorious nosocomial multidrug-resistant pathogen. As a consequence of its recalcitrance to frontline antibiotic therapy, there is an urgent need to develop alternative treatment avenues to tackle this pathogen. One potential alternative infection prevention measure is to seed the wound bed with probiotic bacteria. Several species of Lactobacillus, a common commensal bacterium, have been previously reported to display growth inhibition activity against wound pathogens. Various species of this genus have also been shown to augment the wound healing process, which makes it a promising potential therapeutic agent. Due to the complexity of the burn wound trauma and burn wound infection, an in vivo model is required for the development of novel therapeutics. There are multiple in vivo models that are currently available, the most common among them being the murine model. However, mammalian burn wound infection models are logistically challenging, do not lend themselves to screening approaches and come with significant concerns around ethics and animal welfare. Recently, an invertebrate burn wound and infection model using G. mellonella has been established. This model addresses several of the challenges of more advanced animal models, such as affordability, maintenance and reduced ethical concerns. This study validates the capacity of this model to screen for potential wound probiotics by demonstrating that a variety of Lactobacillus spp . can limit P. aeruginosa burn wound infection and improve survival.

The postburn infections especially antibiotic-resistant bacterial infections have been recognized as a significant and major public health problem. Staphylococcus aureus, Escherichia coli, Acinetobacter, Klebsiella pneumoniae, and Pseudomonas aeruginosa are among very important bacterial pathogens isolated from postburn infections. The present study has evaluated the antimicrobial activity of some plant extracts ( Melissa officinalis and Lawsonia inermis) against some bacterial pathogens causing burn wound infection. The minimal inhibitory concentration (MIC) and the minimal bactericidal concentration (MBC) of the extracts were determined using the microdilution method. Aqueous and alcoholic extracts of L. inermis leaves or powder and hydro-alcoholic extract of M. officinalis were studied. All extracts had the highest antibacterial activity against S. aureus. Although there was no significant difference between antibacterial activity of L. inermis leaves and powder extracts, significant difference was observed between alcoholic and aqueous extracts of this plant. In addition, the results showed that alcoholic extract of L. inermis powder and M. officinalis extracts showed synergistic effect. Overall, these findings support the potential benefits of M. officinalis and L. inermis extracts in the treatment of burn infections. [ABSTRACT FROM AUTHOR]

• GEN&aPDT continuously inhibited the growth and reproduction of planktonic S. aureus and MDR S. aureus for 15 h. • The cell envelope and biofilms of the hospital-acquired multidrug were effectively destroyed by GEN&aPDT. • GEN&aPDT led to changes in the expression of oxidative stress- and Agr system related genes in S. aureus and MDR S. aureus , in which ROS played a regulatory role. • In the burn infection model, GEN&aPDT cotreatment can effectively promote wound healing. Multi-resistant bacteria, partially a result of the abuse of antibiotics, have greatly diminished the effectiveness of antibiotics. The combination of antibiotics with other therapies like antimicrobial photodynamic therapy (aPDT) may provide a useful strategy for fighting resistant bacteria. Here, the synergistic bactericidal effects of toluidine blue (TB)-aPDT and gentamicin (GEN) were evaluated in vitro and in vivo. The Post-antibacterial effects were measured at 600 nm (OD600) by a microplate reader. The bacterial envelope and biofilm were observed by a field emission scanning electron microscope. The expression of oxidative stress and Agr system-related genes was analyzed by qRT-PCR after GEN combined with TB-aPDT (GEN&aPDT). Besides, the burn infection model was established to investigate the cloning efficiency of immobilized bacteria, wound healing and inflammatory factors in the lesions. GEN&aPDT could inhibit the growth of Staphylococcus aureus (S. aureus) and multidrug-resistant S. aureus (MDR S. aureus) for up to 15 h, and destroyed the cell envelope and biofilm structure of S. aureus and MDR S. aureus. During the process, ROS played an important role, inducing oxidative stress and downregulating the expression of AgrA, AgrB and PSM in the Agr system, resulting in decreased bacterial virulence and infectivity. In addition, GEN&aPDT cotreatment could effectively promoted wound healing in burn-infected mice by reducing the numbers of bacterial colonization in the wound, decreasing the content of inflammatory factors, and increasing the expression of growth factors. The present study confirmed a bactericidal synergy between GEN and aPDT in vitro and in vivo , therein, the oxidative stress exhibited an important role in decreasing bacterial virulence and infectivity, which may bring new ideas for the treatment of bacterial resistance. [ABSTRACT FROM AUTHOR]

Abstract: Background: In this experimental animal study, the effects of three different topical antimicrobial dressings on Candida albicans contaminated full-thickness burn in rats were analyzed. Methods: In total 32 adult Wistar rats (body weight 200–220g) were used. Silver-coated dressing (Acticoat™®), chlorhexidine acetate 0.5% (Bactigrass®) and Mycostatine (Nystatin®) were compared to assess the antifungal effect of a once-daily application on experimental rat 15% full-skin thickness burn wound seeded 24h earlier with a 108 CFU/mL standard strain of C. albicans ATCC 90028. All the animals were sacrificed at post burn day 7. The quantitative counts of seeded organism in burn eschar and subjacent muscle were determined, in addition to the cultures of left ventricle blood and lung biopsies. Results: While there were significant differences between Acticoat™® group (4±10×104) and control group (5±6×106), and between Nystatin group (4±4×104) and control group (P =0.01, P =0.01), there were no significant differences between chlorhexidine acetate 0.5% group (2±3×104) and control group (P =0.7) respectively. Acticoat™® and Nystatin were sufficient to prevent to C. albicans from invading to the muscle and from causing systemic infection. Conclusions: The animal data suggest that nystatin is the most effective agents in the treatment of C. albicans-contaminated burn wounds, and Acticoat™® is a choice of treatment on fungal burn wound infection with antibacterial effect and the particular advantage of limiting the frequency of replacement of the dressing. [Copyright &y& Elsevier]

Abstract: Purpose: Topical treatment of burn wounds is essential as reduced blood supply in the burned tissues restricts the effect of systemic antibiotics. On the burn surface, microorganisms exist within a complex structure termed a biofilm, which enhances bacterial resistance to antimicrobial agents significantly. Since bacteria differ in their ability to develop biofilms, the susceptibility of these biofilms to topically applied antibiotics varies, making it essential to identify which topical antibiotics efficiently disrupt or prevent biofilms produced by these pathogens. Yet, a simple in vitro assay to compare the susceptibility of biofilms produced by burn wound isolates to different topical antibiotics has not been reported. Methods: Biofilms were developed by inoculating cellulose disks on agar plates with burn wound isolates and incubating for 24h. The biofilms were then covered for 24h with untreated gauze or gauze coated with antibiotic ointment and remaining microorganisms were quantified and visualized microscopically. Results: Mupirocin and triple antibiotic ointments significantly reduced biofilms produced by the Staphylococcus aureus and Pseudomonas aeruginosa burn wound isolates tested, as did gentamicin ointment, with the exception of one P. aeruginosa clinical isolate. Conclusions: The described assay is a practical and reproducible approach to identify topical antibiotics most effective in eliminating biofilms produced by burn wound isolates. [Copyright &y& Elsevier]

Abstract: In this animal study, three topical antibacterial dressings, Acticoat™, chlorhexidine acetate 0.5% and silver sulfadiazine 1%, were compared in the treatment of Acinetobacter baumannii contamination of burns. All treatments were effective and prevented the organism invading the muscle and causing systemic infection, so there were significant differences between the results of the treatment groups and the control group. Mean eschar concentrations did not differ significantly between the silver sulfadiazine and chlorhexidine acetate groups, but there were significant differences between these and the Acticoat™ group, indicating that Acticoat™ eliminated A. baumannii from the tissues more effectively. [Copyright &y& Elsevier]

Abstract: Infections in burn patients are usually caused by multidrug-resistant micro-organisms. Tigecycline, a derivative of glycylcyclines, is an effective antibiotic against the resistant strains. The aim of this study is to determine the in vitro activity of tigecycline against the multidrug-resistant bacteria isolated from burn patients. Fourty-seven bacteria isolated from 118 patients hospitalized in the burn unit during 2003–2006 were included in the study. Gram-negative bacteria that were resistant to at least six broad-spectrum antibiotics, methicillin-resistant staphylococci and ampicillin-resistant enterococci were studied. Minimal inhibitory concentration values of tigecycline against these bacteria were tested by E-test strips. Susceptibility breakpoints were determined according to the previous studies; ≤0.25mg/L for enterococci, ≤0.5mg/L for staphylococci and ≤2mg/L for Acinetobacter baumannii. Thirty-six percent of the materials were obtained from tissue specimens, 30% from wound, 25% from blood and 9% from other samples (e.g., catheter, tracheal aspiration, urine). MIC90 values were 2, 0.25 and 1.5mg/L and susceptibility rates were 99.4%, 93.6%, 85.5% for A. baumannii, enterococci and MRSA, respectively. To conclude, this study demonstrated that tigecycline exhibits in vitro activity against clinical isolates of MDR A. baumannii, MRSA, and Enterococcus spp. isolated from burn patients. Tigecycline is a promising therapeutic option for difficult to treat burn infections due to these pathogens. [Copyright &y& Elsevier]

Abstract: The goal of this study was to evaluate the efficacy of Alpha ointment in the treatment of burn wounds and compare its results with silver sulfadiazine (SS). Similar burn ulcers were produced on anterior surface of thigh of 60 rats. The wounds were infected with Pseudomonas aeruginosa and dressing and debridement was performed daily. The first group of rats received topical SS, the second group received Alpha ointment and the third (control group) received no medication. Wound healing, contraction, culture, and scar formation were evaluated at the end of the second and 10th week. Alpha ointment was equally effective as SS, considering wound healing and contraction. Wound infection was significantly less common in Alpha ointment group compared to the other two groups (p <0.05). Alpha ointment is a less expensive drug with an acceptable result compared to SS. Therefore, we recommend it as an alternative to SS, especially in patients with low economical backgrounds or in those who show adverse reactions to SS. [Copyright &y& Elsevier]

Abstract: In burn victims, invasion by the bacteria is not unexpected, despite advances in antibiotics, and it has been reported that in the absence of topical therapy, the superficial areas of burn wound contain up to 100 million organisms per gram of tissue within 48h following the injury. We examined the autopsy reports of 334 cases who died because of complicated burns and who underwent medico-legal autopsy during a period of 5 years to study the rate of infection/sepsis. It was observed that in 65% of fatal burn cases, septicemia was the cause of death. Pseudomonas aeuroginosa and Klebsiella sp. were the most common organism, isolated either singly or in combination in 29% and 28% cases, respectively. High mortality from burns in young married women has been recognized as an alarming and contentious problem in India, particularly among the low socio-economic groups. We found that the females aged 21–25 were the most common victims accounting for 37% of burn fatalities due to septicemia. It was concluded that to carry out periodic review of patterns of isolation and susceptibility profiles of microorganisms infecting burn wounds should be a routine in all burn units. In view of the limited resources of developing countries, we recommend the use of available scoring systems to estimate burn outcome so that the best care can be directed to those who have a better chance of improvement. [Copyright &y& Elsevier]

Abstract: Objective: To determine the concordance between superficial cultures (SC) and quantitative cultures (QC) in the diagnosis of wound infection in burn patients. Method: Sample: All SC and QC taken from the same patient, site and during the same surgery were analysed. Variables: On the SC, the microorganism (MO) and its amount defined subjectively by the microbiologist was recorded (negative, very low, low, regular and abundant). On the QC, the MO and its amount were expressed as colony forming units per gram of tissue (CFUs/g). Statistics: Kappa index of agreement beyond chance; Wilcoxon and Kruskall-Wallis for continuous variables and χ 2 for categorical variables were used with a p <0.05 indicating statistical significance. Results: One thousand four hundred and forty three pairs of cultures were analyzed. The concordance between SC and QC (Kappa index) was 52%. On the SC, only when the microbiologist subjectively informed “abundant” MOs there was a significant difference (p <0.0001). There were 6.1% of QCs with more than 105 CFUs/g and the most frequent MOs isolated were: S. aureus (27.9%), E. coli (11.6%), P. aeruginosa (11.6%), E. faecalis (11.6%) and S. epidermidis (7.0%). Conclusions: SC has a moderate concordance with the QC showing a low reliability between the two methods. The subjective information given by the microbiology technician in the SC is not precise. A study in which the two methods be compared blindly against the reference standard, in a prospective cohort of patients, it is needed to discriminate which of two methods it is the most accurate one determining sensitivity and specificity. [Copyright &y& Elsevier]

Resistance to silver compounds as determined by bacterial plasmids and genes has been defined by molecular genetics. Silver resistance conferred by the Salmonella plasmid pMGH100 involves nine genes in three transcription units. A sensor/responder (SilRS) two-component transcriptional regulatory system governs synthesis of a periplasmic Ag(I)-binding protein (SilE) and two efflux pumps (a P-type ATPase (SilP) plus a three-protein chemiosmotic RND Ag(I)/H+ exchange system (SilCBA)). The same genes were identified on five of 19 additional IncH incompatibility class plasmids but thus far not on other plasmids. Of 70 random enteric isolates from a local hospital, isolates from catheters and other Ag-exposed sites, and total genomes of enteric bacteria, 10 have recognizable sil genes. The centrally located six genes are found and functional in the chromosome of Escherichia coli K-12, and also occur on the genome of E. coli O157:H7. The use of molecular epidemiological tools will establish the range and diversity of such resistance systems in clinical and non-clinical sources. Silver compounds are used widely as effective antimicrobial agents to combat pathogens (bacteria, viruses and eukaryotic microorganisms) in the clinic and for public health hygiene. Silver cations (Ag+) are microcidal at low concentrations and used to treat burns, wounds and ulcers. Ag is used to coat catheters to retard microbial biofilm development. Ag is used in hygiene products including face creams, ‘alternative medicine’ health supplements, supermarket products for washing vegetables, and water filtration cartridges. Ag is generally without adverse effects for humans, and argyria (irreversible discoloration of the skin resulting from subepithelial silver deposits) is rare and mostly of cosmetic concern. [Copyright &y& Elsevier]

Antimicrobial resistance-related infections of Gram-negative pathogens pose a huge threat to global public health. Lysins, peptidoglycan hydrolases from bacteriophages, are expected as an alternative weapon against drug-resistant bacteria. In the present study, we report a new lysin LysP53 from Acinetobacter baumannii phage 53. Bioinformatic analysis revealed that LysP53 contains a positively charged N-terminal region and a putative peptidase catalytic domain. In vitro biochemical experiments showed that LysP53 is active against multiple antibiotic-resistant Gram-negative bacteria, including A. baumannii , Pseudomonas aeruginosa , Klebsiella pneumoniae , and Escherichia coli , with a reduction of 5 logs in viable A. baumannii number after exposure to 100 μg/mL LysP53 for 1 h. Further studies showed that LysP53 contains a functional antimicrobial peptide, i.e., N-terminal 33 aa, with a comparable spectrum of activity to LysP53. In an A. baumannii -associated mouse model of burn infection, a single dose of 14 μg/mouse LysP53 (57.6 μM) showed higher decolonization efficacy than 4 μg/mouse minocycline- (874 μM; p < 0.05) and buffer-treated groups ( p <0.001), leading to a bacterial reduction of 3 logs. Our findings collectively establish that LysP53 could be a promising candidate in the treatment of topical infections caused by multiple Gram-negative pathogens.

Objective: The incidence of severe infectious complications after burn injury increases mortality by 40%. However, traditional approaches for managing burn infections are not always effective. High-voltage, pulsed electric field (PEF) treatment shortly after a burn injury has demonstrated an antimicrobial effect in vivo ; however, the working parameters and long-term effects of PEF treatment have not yet been investigated. Approach: Nine sets of PEF parameters were investigated to optimize the applied voltage, pulse duration, and frequency or pulse repetition for disinfection of Pseudomonas aeruginosa infection in a stable mouse burn wound model. The bacterial load after PEF administration was monitored for 3 days through bioluminescence imaging. Histological assessments and inflammation response analyses were performed at 1 and 24 h after the therapy. Results: Among all tested PEF parameters, the best disinfection efficacy of P. aeruginosa infection was achieved with a combination of 500 V, 100 μs, and 200 pulses delivered at 3 Hz through two plate electrodes positioned 1 mm apart for up to 3 days after the injury. Histological examinations revealed fewer inflammatory signs in PEF-treated wounds compared with untreated infected burns. Moreover, the expression levels of multiple inflammatory-related cytokines (interleukin [IL]-1α/β, IL-6, IL-10, leukemia inhibitory factor [LIF], and tumor necrosis factor-alpha [TNF-α]), chemokines (macrophage inflammatory protein [MIP]-1α/β and monocyte chemoattractant protein-1 [MCP-1]), and inflammation-related factors (vascular endothelial growth factor [VEGF], macrophage colony-stimulating factor [M-CSF], and granulocyte-macrophage colony-stimulating factor [G-CSF]) were significantly decreased in the infected burn wound after PEF treatment. Innovation: We showed that PEF treatment on infected wounds reduces the P. aeruginosa load and modulates inflammatory responses. Conclusion: The data presented in this study suggest that PEF treatment is a potent candidate for antimicrobial therapy for P. aeruginosa burn infections.

Peroxidase-mimicking nanozymes that can generate toxic hydroxyl radicals ( . OH) hold great promise as antibacterial alternatives. However, most of them display optimal performance under strongly acidic conditions (pH 3-4), and are thus not feasible for many medical uses, including burn infections with a wound pH close to neutral. Herein, we report a copper-based nanozyme (CuCo 2 S 4 ) that exhibits intrinsic peroxidase-like activity and can convert H 2 O 2 into . OH at neutral pH. In particular, bimetallic CuCo 2 S 4 nanoparticles (NPs) exhibited enhanced peroxidase-like activity and antibacterial capacity, superior to that of the corresponding monometallic CuS and CoS NPs. The CuCo 2 S 4 nanozymes possessed excellent ability to kill various bacteria, including methicillin-resistant Staphylococcus aureus (MRSA). Furthermore, this CuCo 2 S 4 nanozymes could effectively disrupt MRSA biofilms in vitro and accelerate MRSA-infected burn healing in vivo. This work provides a new peroxidase mimic to combat bacteria in neutral pH milieu and this CuCo 2 S 4 nanozyme could be a promising antibacterial agent for the treatment of burn infections., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)