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3D‐printed scaffolds can better mimic the function of human skin, both biologically and mechanically. Within the scope of this study, the effect of the addition of different amounts (10, 15, 20 mg) of gentamicin sulfate (GS) to a 10 mL solution of natural and synthetic polymers is investigated. Sodium alginate (SA), gelatin‐methacryloyl (GelMA), and polyvinyl alcohol (PVA) are chosen as bioactive materials. The surface morphology and pore structures are visualized by scanning electron microscopy (SEM). According to the results, it is observed that the pore sizes of all scaffolds are smaller than 270 µm, the lowest value (130 µm) is obtained in the scaffold loaded with 15 mg GS, and it also has the highest tensile strength value (12.5 ± 7.6 MPa). Similarly, it is observed that the tensile strength (9.7 ± 4.5 MPa) is high in scaffold loaded with 20 mg GS. The biocompatibility test is performed with fibroblast cells, and the results show that the scaffolds are biocompatible with cells. The antibacterial test is carried out against the S.aureous and E. coli and the results indicate that all GS‐loaded scaffolds demonstrate antibacterial activity. [ABSTRACT FROM AUTHOR]

This study compared the cytotoxicity and antimicrobial activity of hypochlorous acid (HOCl) at 50 ppm and 200 ppm and 0.2% chlorhexidine (CHX) at various time intervals, in vitro. Cell viability and cytotoxicity of human gingival fibroblasts (HGF) were evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test and the lactate dehydrogenase assay. Antimicrobial effects on Aggregatibacter actinomycetemcomitans and Candida albicans were determined using the time-kill method. All solutions exhibited a significant impact on HGFs in a dose- and time-dependent manner. 50 ppm HOCl demonstrated the highest cell viability, followed by 200 ppm HOCl. Both HOCl solutions were less cytotoxic to HGFs than 0.2% CHX. 50 ppm and 200 ppm HOCl demonstrated stronger efficiencies than CHX against A. actinomycetemcomitans and C. albicans. The data suggest that HOCl solutions have potential as an alternative antiseptic to CHX due to their lower cytotoxicity and superior antimicrobial activity, but optimal dosage of HOCl requires further investigations. [ABSTRACT FROM AUTHOR]

The aim is to investigate how Umbilical Cord-Derived Mesenchymal Stem Cells conditioned medium (UC-MSC-CM) can promote wound healing and epithelial barrier function. UC-MSCs were differentiated into osteocytes, adipocytes, and chondrocytes to determine their multipotency. Flow cytometric analyses confirmed positive surface markers (CD90, CD73, CD105) and the absence of negative markers (CD34, CD11b, CD19, HLA_DR). We prepared conditioned medium (CM) from these cells. UC-MSC CM was tested in in vitro wound healing experiments using scratch assays and transepithelial electrical resistance measurements at 6th, 12th, and 24th hours to assess its regenerative effects. UC-MSCs were found to be multipotent in the characterization and differentiation analysis, demonstrating their potential for use in regenerative medicine. In our wound model design, UC-MSC-CM significantly accelerated the healing process 75% and 92.7% at 12 and 24 hours respectively compared to the control group. According to TEER analyzes epithelial barrier resistance showed 200 O.cm2 with UC-MSC-CM healing process at the 12th and 24th hours while the control group showed 145 O.cm2 and 185 O.cm2 at the same time points, respectively. The study demonstrates the potential of UC-MSCs in repairing epithelial barriers and wound injuries. The UC-MSCCM accelerates wound closure as the healing process advances and enhances barrier integrity and permeability. These findings highlight UC-MSC-CM as a cell-free therapy for regenerative medicine and wound healing. Further research should focus on understanding the underlying mechanisms and optimizing its therapeutic applications to revolutionize wound management and treatment. [ABSTRACT FROM AUTHOR]

Purpose: This study was conducted to compare dental plaque scores obtained through clinical examinations and various imaging techniques, as well as to assess the effectiveness of herbal and conventional toothpastes for plaque removal. Materials and Methods: Thirty volunteers were divided into 3 groups. Each group was given a different toothpaste (from 2 herbal toothpastes and a conventional toothpaste) with which to brush their teeth for 21 days. Both initially and after brushing, dental plaque samples were collected, and plaque on the buccal surfaces of anterior teeth was scored using several imaging systems after staining with a disclosing agent. Specifically, digital dental photography, intraoral digital scanning, and FluoreCam imaging were employed to capture intraoral images. The Turesky Modified QuigleyHein Plaque Index was used for clinical examination and image analysis. Quantitative polymerase chain reaction analyses and correlational assessments between clinical examination and imaging scores were conducted before and after toothpaste use. The Shapiro-Wilk test and Pearson correlations were utilized. Results: The lowest mean value was observed in the clinical examination without staining, while the highest was obtained using the FluoreCam method. No significant change was found in the level of any microorganism assessed following toothpaste use (P<0.05), with the exception of a decrease in S. mutans levels after using conventional toothpaste (P<0.05). Conclusion: Herbal toothpaste demonstrated plaque-removal effectiveness comparable to that of conventional toothpaste. The use of imaging methods for measuring plaque index has been suggested as a means to educate patients about plaque control and promote ongoing oral care. [ABSTRACT FROM AUTHOR]

Infections caused by antibiotic-resistant pathogens pose a major threat worldwide. There is an urgent need to develop effective strategies to solve this problem. The antibacterial activity of adult mesenchymal stem cells (MSCs) has recently been determined against various bacterial isolates. New approaches, such as Toll-like receptor activation, were used to enhance their antibacterial potency. This study examines the antibacterial activity of TLR agonist (TLR2/TLR1 and/or TLR2/TLR6) activated adipose-derived canine MSCs (AD-MSCs) on multi)drug resistant isolates including Staphylococcus aureus, Escherichia coli, Enterococcus faecalis, and Pseudomonas aeruginosa regarding bacterial growth, and minimum inhibitory concentration (MIC) determination. Effects on bacterial morphology were assessed by electron microscopy. Our results showed that the AD-MSCs conditioned medium primed with different TLR agonists inhibited the growth of E. coli and S. aureus, but it had a decreased effect on E. faecalis and P. aeruginosa. Despite this, AD-MSCs conditioned medium prepared with the combination of TLR agonists exhibited antibacterial activity against all isolates. These findings were in parallel with MIC levels of conditioned media. We conclude that adipose-derived canine MSCs primed with TLR agonists (TLR2/TLR1 and TLR2/TLR6 combination) possess antimicrobial activity against multi-drug resistant isolates of E. coli, S. aureus, E. faecalis and P. aeruginosa. Further studies for testing in in vivo models are being planned to assess the potential application of AD-MSCs as an adjunct treatment modality for multi drug resistant infections. [ABSTRACT FROM AUTHOR]

In this study, a dental membrane scaffold was fabricated using a 3D printing technique, and the antimicrobial effect of pomegranate seed and peel extract were investigated. For the production of the dental membrane scaffold, a combination of polyvinyl alcohol, starch, and pomegranate seed and peel extracts was used. The aim of the scaffold was to cover the damaged area and aid in the healing process. This can be achieved due to the high antimicrobial and antioxidant content of pomegranate seed and peel extracts (PPE: PSE). Moreover, the addition of starch and PPE: PSE improved the biocompatibility of the scaffold, and their biocompatibility was tested using human gingival fibroblast (HGF) cells. The addition of PPE: PSE into the scaffolds resulted in a significant antimicrobial effect on S. aureus and E. faecalis bacteria. Moreover, different concentrations of starch (1%, 2%, 3% w/v) and pomegranate peel and seed extract (3%, 5%, 7%, 9%, and 11% PE v/v) were analyzed to obtain the ideal dental membrane structure. The optimum starch concentration was chosen as 2% w/v due to it giving the scaffold the highest mechanical tensile strength (23.8607 ± 4.0796 MPa). The pore sizes of each scaffold were studied by SEM analysis, and pore sizes were arranged between 155.86 and 280.96 μm without any plugging problems. Pomegranate seed and peel extracts were obtained by applying the standard extraction method. High-performance liquid chromatography was performed using the diode-array detection (HPLC-DAD) technique to analyze the phenolic content of the pomegranate seed and peel extracts. Two phenolic components of the pomegranate seed and peel extracts were investigated in the following amounts: fumaric acid (17.56 μg analyte/mg extract) and quinic acid (18.79 μg analyte/mg extract) in pomegranate seed extract and fumaric acid (26.95 μg analyte/mg extract) and quinic acid (33.79 μg analyte/mg extract) in pomegranate peel extract. [ABSTRACT FROM AUTHOR]

Aim: In this study, we examined the factors affecting the psychological symptoms and quality of life of the caregiver parents of the cerebral palsy patients. Materials and Methods: This cross-sectional study was conducted between May-September 2013 in fifty CP patients and their caregivers. Demographic information, parents' education, family type, households, patients' siblings, drug usage, rehabilitation hospitalizations (NoRH), and gross motor function levels were recorded. The caregivers completed the psychometric symptom checklist (SCL-90-R) and the QoL questionary (SF-36). Factors affecting SCL-90-R and SF-36 were evaluated by correlation and regression analysis. Results: The proportion of symptomatic parents in the psychiatric evaluation ranged from 26% to 58% in subheadings. Psychological symptoms were mostly correlated with low QoL. Quality of life was lower than the population average in all subheadings. GHI and paranoid thoughts were positively correlated with NoRH. Households' number was negatively correlated with NoRH (p=0.045, p=0.032, p=0.025). Interpersonal sensitivity and the siblings' number were positively correlated (p=0.005). Father's primary school graduation was a risk factor for increased anxiety (OR=0.446, p=0.030). The female CP was a risk for paranoid thoughts (OR=0.410, p=0.025). For SF-36, median scores were low in all components. The nuclear family was a risk factor for low physical components score (OR=-8.123, p=0.009). Not using any medications was a risk factor for a lower mental component score (OR=7.953, p=0.008). Conclusion: The caregiver parents had low QoL and more psychological symptoms. Public healthcare policymakers should plan projects to improve the psychological health and QOL of caregivers. [ABSTRACT FROM AUTHOR]

Skin diseases are commonly treated with antihistamines, antibiotics, laser therapy, topical medications, local vitamins, or steroids. Since conventional treatments for wound healing (skin allografts, amnion, xenografts, etc.) have disadvantages such as antigenicity of the donor tissue, risk of infection, or lack of basement membrane, skin tissue engineering has become a popular new approach. The current study presents the design and fabrication of a new wound-dressing material by the addition of Juglone (5-hydroxy-1,4-naphthoquinone) to a 25% Polycaprolactone (PCL) scaffold. Juglone (J) is a significant allelochemical found in walnut trees and, in this study is used as a bioactive material. The effects of different amounts of J (1.25, 2.5, 5, 7.5, and 10 mg) on the biocompatibility, mechanical, chemical, thermal, morphological, and antimicrobial properties of the 3D-printed 25% PCL scaffolds were investigated. The addition of J increased the pore diameter of the 25% PCL scaffold. The maximum pore size (290.72 ± 14 µm) was observed for the highest amount of J (10 mg). The biocompatibility tests on the scaffolds demonstrated biocompatible behavior from the first day of incubation, the 25% PCL/7.5 J scaffold having the highest viability value (118%) among all of the J-loaded scaffolds. Drug release of J into phosphate buffered saline (PBS) at pH 7.4 showed that J was completely released from all 25% PCL/J scaffolds within 7 days of incubation. [ABSTRACT FROM AUTHOR]

Management of wastewater (WW) and protection of the aquatic ecosystem have become a major problem recently. Our objective was to determinate the chemical load and genotoxic potential of WWs before and after advance treatment, and also to foresee whether the pollutants harm the receiving environments where they were discharged. WW samples were collected from influent and effluent of an advanced wastewater treatment plant (AWTP) and discharge of School of Medicine (SoM). Spectrophotometric analyses showed that Pb levels in WWs were found to be over the cut of f limit independent from seasonal change. Nitrogen (N) load is detected quite high before the treatment process. According to AMES test, mutagenic effect of AWTP in the absence of liver enzymes were found to be higher in influent (IR: 7.15; TA100) whereas lower in effluent (IR: 4.04; TA100). According to our results, advanced biological treatment might be insufficient in adequate elimination of Pb, N and P. However, further studies are required to validate our results. [ABSTRACT FROM AUTHOR]

Copyright of Journal of the Society of Thoracic Carido-Vascular Anaesthesia & Intensive Care is the property of Gogus Kalp Damar Anestezi ve Yogun Bakim Dernegi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Juglone (5-hydroxy-1,4-naphthoquinone) (J) is a naphthoquinone structured allelochemical that is mostly found in the roots, leaves, nut-hulls, bark, and wood of walnut (Juglans regia). In this study, the biocompatibility, mechanical, thermal, chemical, morphological, and antimicrobial properties of the poly(lactic acid) (PLA) (w/v)/J (10, 20, 30 mg) electrospun scaffolds were investigated. Based on the results of the study, it was shown that juglone addition increased the antimicrobial properties of the scaffolds against the Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), compared to the neat PLA film after 24 h of contact time. According to the tensile test results, the addition of J made the scaffolds more flexible but decreased the mechanical strength. The cytotoxicity properties of the J-added scaffolds demonstrated a toxic behavior on the first day of incubation. However, with an increase in the J ratio, the fibroblast cell metabolic activity increased for all incubation periods. [ABSTRACT FROM AUTHOR]

Objective: In this study, we aimed to compare the efficiency of different immobilization media to facilitate breakdown of whey proteins by Streptococcus thermophilus (S. thermophilus). Materials and Methods: S. thermophilus was isolated from yoghurt. High-protein whey powder was present in fermentation media and two-phase dispersion technique was used for immobilization of S. thermophilus in agar, agarose and κ-carrageenan. Total protein after fermentation of whey proteins with S. thermophilus in different media was measured. We have also performed sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis to observe changes in individual whey proteins after fermentation in different media. Results: Total protein concentration showed a significant decrease at the end of 24 hours of fermentation in all media. SDS-PAGE results showed that the amount of both α-lactalbumin and β-lactoglobulin were reduced in all immobilization media compared to control. The effect of κ-carrageenan was considerably higher compared to other media. Conclusion: Our results showed that immobilization in κ-carrageenan increased the breakdown of whey proteins by S. thermophilus and can be used to increase fermentation efficiency. [ABSTRACT FROM AUTHOR]

Objective: Nowadays, the treatment of infections caused by hospital-acquired resistant bacteria has become very difficult. It is known that hospital infections can be limited and kept to a minimum with the use of appropriate sterilization--disinfection methods. In our study, we aimed to investigate the inhibition effect of ozone--which is low cost, has a nontoxic effect on humans, and does not leave chemical residues and wastes--on resistant microorganisms that cause nosocomial infections. Methods: In this study, 80 strains of bacteria with various resistance patterns and isolated as a causative agent of nosocomial infection were included. Ten strains of each bacterium-- MRSA, VRE, MDR Pseudomonas aeruginosa, ESBL (+) Klebsiella pneumoniae, carbapenemase (+) K. pneumoniae, colistin-resistant K. pneumoniae, colistin-resistant Acinetobacter baumannii complex, and colistin sensitive A. baumannii complex--were used. One liter of sterile distilled water (DW) was saturated with ozone for 1 h. A quantity of 0.1 mL of bacterial suspension was added onto 9.9 mL ozonated DW (final bacterial concentration 106 cfu/mL). From the suspensions kept at room temperature, samples were inoculated as a count plate on sheep blood agar with a 10 µL calibrated loop at 10 and 30 min. After 24 h of incubation, the number of growing colonies was calculated by evaluating the Petri dishes. Results: The bacterial inhibition rates of ozonated water at 10 and 30 min exposure times were detected as 97.29--100% for Gram-positive nosocomial-resistant pathogens and 94.76-- 99.99% for Gram-negative nosocomial-resistant pathogens, respectively. Conclusion: It has been determined that ozonated water can provide a very high antibacterial effect in vitro at a very low cost. In other studies, the antiviral activity of ozone, including SARS-CoV-2, has also been shown. The data we obtained suggest that ozone can be used in various disinfection--sterilization processes in hospitals. We believe that a cost-effective solution can be produced by supporting such studies with clinical research. [ABSTRACT FROM AUTHOR]

Amphiphilic poly(oxanorbornene)s are promising synthetic polymers that mimic the structural properties and antimicrobial functions of naturally occurring antimicrobial peptides. Here, poly(oxanorbornene)s bearing pendant zinc(II) phthalocyanine and triphenyl(ethyl) phosphonium functionalities are synthesized by ring‐opening metathesis polymerization (ROMP). Fluorescence, singlet oxygen and triplet quantum yields of polymers are measured in dimethyl sulfoxide and aqueous medium. The singlet oxygen quantum yields of copolymers with the highest triphenyl and triethyl phosphonium content are found to be 0.29 and 0.41, respectively. Then, antimicrobial activities of polymers against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) are investigated under both dark and light conditions. Synergistic effect of zinc(II) phthalocyanine and phosphonium‐containing poly(oxanorbornene) is observed that the conjugate possessing the most triphenyl phosphonium side chains has the highest activity under light against both gram‐positive and gram‐negative bacterial strains after 80 min irradiation, reducing the survival of E. coli or S. aureus by 99.9999%. Hemolytic concentrations of the copolymers are found between 8 and 512 µg mL−1. Scanning electron microscopy (SEM) proves that the bacteria membrane deforms after contacting with the biocidal polymer. [ABSTRACT FROM AUTHOR]

Urinary tract infections are one of the most common bacterial infections and rapid diagnosis of the infection is essential for appropriate antibiotic therapy. The goal of our study was to identify urinary pathogens directly by MALDI-TOF MS and to perform antibiotic susceptibility tests in order to shorten the period spent for culturing. Urine samples submitted for culture to the Clinical Microbiology Laboratory were enrolled in this study. Urine samples were screened for leukocyte and bacteria amount by flow cytometry. Samples with bacterial load of 106–107/mL were tested directly by MALDI-TOF MS and antibiotic susceptibility tests (AST) were performed. In total, 538 positive urine samples were evaluated in our study. MALDI-TOF MS identified the microorganism directly from the urine sample in 91.8% of these samples and the concordance rate of conventional identification and direct detection was 95.8% for Gram-negatives at the genus and species level. Escherichia coli (n :401) was the most frequently isolated microorganism, followed by Klebsiella pneumoniae (n :57). AST results were generated for 111 of these urine samples and the concordance was 90% and 87% for E. coli and K. pneumoniae , respectively. Our results showed that screening of urine samples with flow cytometry to detect positive samples and identification of uropathogens directly by MALDI-TOF MS with an accuracy of over 90% can be a suitable method particularly for Gram-negative bacteria in clinical microbiology laboratories. [ABSTRACT FROM AUTHOR]

High-fat diet (HFD) consumption leads to metabolic disorders, gastrointestinal dysfunction and intestinal dysbiosis. Antibiotics also disrupt the composition of intestinal microbiota. The aim of the present study was to investigate the impact of a short-term feeding with HFD on oxidative status, enteric microbiota, intestinal motility and the effects of antibiotics and/or melatonin treatments on diet-induced hepato-intestinal dysfunction and inflammation. Male Sprague–Dawley rats were pair-fed with either standard chow or HFD (45 % fat) and were given tap water or melatonin (4 mg/kg per d) or melatonin plus antibiotics (ABX; neomycin, ampicillin, metronidazole; each 1 g/l) in drinking water for 2 weeks. On the 14th day, colonic motility was measured and the next day intestinal transit was assessed using charcoal propagation. Trunk blood, liver and intestine samples were removed for biochemical and histopathological evaluations, and faeces were collected for microbiota analysis. A 2-week HFD feeding increased blood glucose level and perirenal fat weight, induced low-level hepatic and intestinal inflammation, delayed intestinal transit, led to deterioration of epithelial tight junctions and overgrowth of colonic bacteria. Melatonin intake in HFD-fed rats reduced ileal inflammation, colonic motility and perirenal fat accumulation. ABX abolished increases in fat accumulation and blood glucose, reduced ileal oxidative damage, suppressed HFD-induced overgrowth in colonic bacteria, and reversed HFD-induced delay in intestinal transit; however, hepatic neutrophil accumulation, hepatic injury and dysfunction were further enhanced. In conclusion, the results demonstrate that even a short-term HFD ingestion results in hepato-intestinal inflammatory state and alterations in bacterial populations, which may be worsened with antibiotic intake, but alleviated by melatonin. [ABSTRACT FROM AUTHOR]

Objective To investigate the effects of plant-derived phenolic compounds ( i.e. caffeic acid, cinnamic acid, ferulic acid and vanillic acid) on the production of quorum sensing regulated virulence factors such as pyocyanin, biofilm formation and swarming motility of Pseudomonas aeruginosa ( P. aeruginosa ) isolates. Methods Fourteen clinical P. aeruginosa isolates obtained from urine samples and P. aeruginosa PA01 strain were included in the study. The antibacterial effects of phenolic compounds were screened by well diffusion assay. Pyocyanin and biofilm activity were measured from culture supernatants and the absorbance values were measured using a spectrophotometer. Swarming plates supplemented with phenolic acids were point inoculated with P. aeruginosa strains and the ability to swarm was determined by measuring the distance of swarming from the central inoculation site. Results Tested phenolic compounds reduced the production of pyocyanin and biofilm formation without affecting growth compared to untreated cultures. Moreover, these compounds blocked about 50% of biofilm production and swarming motility in P. aeruginosa isolates. Conclusions We may suggest that if swarming and consecutive biofilm formation could be inhibited by the natural products as shown in our study, the bacteria could not attach to the surfaces and produce chronic infections. Antimicrobials and natural products could be combined and the dosage of antimicrobials could be reduced to overcome antimicrobial resistance and drug side effects. [ABSTRACT FROM AUTHOR]

In this study, an experimental investigation of oblique cuttingprocess is presented for titanium alloy Ti-6Al-4V, AISI 4340, andAl 7075. Important process parameters such as shear angle, friction angle, shear stress, and chip flow angle are analyzed. Transformation of the data from the orthogonal cutting test results to oblique cutting process is applied, and the results are compared with actual oblique cutting tests. Effects of hone radius on cutting forces and flank contact length are also investigated. It is observed that the shear angle, friction angle, and shear stress in oblique cutting have the same trend with the ones obtained from the orthogonal cutting tests. The transformed oblique force coefficients from orthogonal tests have about 10% discrepancy in the feed and tangential directions. For the chip flow angle, the predictions based on kinematic and force balance results yield better results than Stabler's chip flow law. Finally, it is shown that the method of oblique transformation applied on the orthogonal cutting data yields more accurate results using the predicted chip flow angles compared to the ones obtained by the Stabler's rule. [ABSTRACT FROM AUTHOR]

Purpose: The effect of extremely low frequency electromagnetic fields (ELF-EMF) on bacteria has attracted attention due to its potential for beneficial uses. This research aimed to determine the effect of ELF-EMF on bacterial membrane namely the membrane potential, surface potential, hydrophobicity, respiratory activity and growth. Materials and methods: Gram-positiveStaphylococcus aureusand Gram-negativeEscherichia coliwere subjected to ELF-EMF, 50 Hz, 1 mT for 2 h. Membrane potential was determined by fluorescence spectroscopy with or without EDTA (Ethylenediaminetetraacetic acid) with DisC3(5) (3,3-dipropylthiacarbocyanine iodide), zeta potential measurements were performed by electrophoretic mobility, hydrophobicity of the membrane was measured with MATH (Microbial Adhesion to Hydrocarbons) test, respiratory activity was determined with CTC (5-Cyano-2,3-ditolyl tetrazolium chloride), colony forming unit (CFU) and DAPI (4′,6-diamidino-2-phenylindole, dihydrochloride) was used for growth determinations. Results: ELF-EMF caused changes in physicochemical properties of both Gram-positive and Gram-negative bacteria. Hyperpolarization was seen inS. aureusand EDTA-treatedE. coli. Surface potential showed a positive shift inS. aureuscontrariwise to the negative shift seen in EDTA-untreatedE. coli. Respiratory activity increased in both bacteria. A slight decrease in growth was observed. Conclusion: These results show that ELF-EMF affects the crucial physicochemical processes in both Gram-positive and Gram-negative bacteria which need further research. [ABSTRACT FROM AUTHOR]

Purpose: To determine the effect of extremely low frequency (<300 Hz) electromagnetic fields (ELF-EMF) on the growth rate of Gram-positive and Gram-negative bacteria and to determine any morphological changes that might have been caused by ELF-EMF. Materials and methods: Six bacterial strains, three Gram-negative and three Gram-positive were subjected to 50 Hz, 0.5 mT ELF-EMF for 6 h. To determine growth rate after ELF-EMF application, bacteria exposed to ELF-EMF for 3 h were collected, transferred to fresh medium and cultured without field application for another 4 h. Growth-rate was determined by optical density (OD) measurements made every hour. Morphological changes were determined with Transmission electron microscopy (TEM) for two gram-negative and two gram-positive strains collected after 3 h of field application. Results: A decrease in growth rate with respect to control samples was observed for all strains during ELF-EMF application. The decrease in growth-rate continued when exposed bacteria were cultured without field application. Significant ultrastructural changes were observed in all bacterial strains, which were seen to resemble the alterations caused by cationic peptides. Conclusion: This study shows that ELF-EMF induces a decrease in growth rate and morphological changes for both Gram-negative and Gram-positive bacteria. [ABSTRACT FROM AUTHOR]

In this research, polyvinyl-alcohol (PVA)/gelatin (GEL)/propolis (Ps) biocompatible nanofiber patches were fabricated via electrospinning technique. The controlled release of Propolis, surface wettability behaviors, antimicrobial activities against the S. aureus and P. aeruginosa, and biocompatibility properties with the mesenchymal stem cells (MSCs) were investigated in detail. By adding 0.5, 1, and 3 wt.% GEL into the 13 wt.% PVA, the morphological and mechanical results suggested that 13 wt.% PVA/0.5 wt.% GEL patch can be an ideal matrix for 3 and 5 wt.% propolis addition. Morphological results revealed that the diameters of the electrospun nanofiber patches were increased with GEL (from 290 nm to 400 nm) and Ps addition and crosslinking process cause the formation of thicker nanofibers. The tensile strength and elongation at break enhancement were also determined for 13 wt.% PVA/0.5 wt.% GEL/3 wt.% Ps patch. Propolis was released quickly in the first hour and arrived at a plateau. Cell culture and contact angle results confirmed that the 3 wt.% addition of propolis reinforced mesenchymal stem cell proliferation and wettability properties of the patches. The antimicrobial activity demonstrated that propolis loaded patches had antibacterial activity against the S. aureus, but for P. aeruginosa, more studies should be performed. [ABSTRACT FROM AUTHOR]

In this study, the main aim was to fabricate propolis (Ps)-containing wound dressing patches using 3D printing technology. Different combinations and structures of propolis (Ps)-incorporated sodium alginate (SA) scaffolds were developed. The morphological studies showed that the porosity of developed scaffolds was optimized when 20% (v/v) of Ps was added to the solution. The pore sizes decreased by increasing Ps concentration up to a certain level due to its adhesive properties. The mechanical, swelling-degradation (weight loss) behaviors, and Ps release kinetics were highlighted for the scaffold stability. An antimicrobial assay was employed to test and screen antimicrobial behavior of Ps against Escherichia coli and Staphylococcus aureus strains. The results show that the Ps-added scaffolds have an excellent antibacterial activity because of Ps compounds. An in vitro cytotoxicity test was also applied on the scaffold by using the extract method on the human dermal fibroblasts (HFFF2) cell line. The 3D-printed SA–Ps scaffolds are very useful structures for wound dressing applications. [ABSTRACT FROM AUTHOR]