Assessment of synergistic activity of rhamnolipid and linezolid against methicillin-resistant Staphylococcus aureus in-vitro and in-vivo with Galleria mellonella larvae model.

Antibiotic resistance, one of the most crucial public health problems, has increased the interest in synergy studies of antibiotics with existing antibiotics and natural compounds to make current treatment more effective in addition to new drug development. In this study, the effectiveness of rhamnolipid and linezolid on the Galleria mellonella larvae model in-vitro and in-vivo against Methicillin-resistant Staphylococcus aureus isolates, which are problematic in treatment, were investigated. Four S.aureus (One ATCC 29213 strain and three methicillin-resistant strains) were used in the study. Two MRSA isolates were resistant to linezolid, and one was susceptible. Partial synergy was observed in one resistant strain, and although no synergy was observed in the other resistant strain, the minimum inhibitory concentration of the resistant strain decreased from 16 to 4 µg/mL with a four-fold decrease and reached the susceptibility limit. No change was observed in the MIC of linezolid-susceptible strains. The G.mellonella larval model demonstrated that combined therapy was more effective than monotherapy by survival function tests and CFU determination. RML/LNZ combination improved survival compared to monotherapy and decreased the bacterial burden from 108 to 103.

Demonstration of the efficacy of curcumin on carbapenem-resistant Pseudomonas aeruginosa with Galleria mellonella larvae model.

Due to increasing antimicrobial resistance, studies where new treatment options are investigated along with the synergistic effects of natural products with antibiotics have arisen. Pseudomonas aeruginosa (P. aeruginosa) is an opportunistic pathogen and infection with multi-drug resistant (MDR) P. aeruginosa poses a critical problem during treatment. Curcumin (CUR) is listed in the literature as one of the promising natural ingredients with its strong antimicrobial activity. In our study, our aim was to investigate the in vitro synergistic effect of CUR with imipenem (IMP) and Colistin (CST) in MDR P. aeruginosa isolates and in vivo activity on Galleria mellonella (G. mellonella) larvae. Three clinical isolates of MDR P. aeruginosa, which were determined to be phenotypically resistant to carbapenems, were used, and KPC and OXA48 resistance genes were determined by PCR method. The synergistic effect of CUR with antibiotics were investigated by the checkerboard method. Larval survival and bacterial load were compared with the in vivo study. In this study, IMP MIC values were significantly reduced (two to eight-fold decrease) in the presence of CUR, and partial synergy was observed. For CST, this value decreased two-fold. Bacterial load was evaluated to investigate the effect of antimicrobials during infection. While the CFUs increased over time in non-treated larvae as compared to the initial inoculum, bacterial load was significantly decreased for the groups treated with CUR, IMP and CST compared to the untreated group (p < 0.05). It was concluded CUR-antibiotic combinations can provide an alternative approach in the treatment of infections with MDR bacteria.

The comparison of lytic activity of isolated phage and commercial Intesti bacteriophage on ESBL producer E. coli and determination of Ec_P6 phage efficacy with in vivo Galleria mellonella larvae model.

Antibiotic resistance is one of the crucial public health challenges. As a result of rising resistance, as an alternative to antimicrobials, demands for bacteriophage therapy have increased significantly over the years. The objective of this study was to isolate and characterize potentially therapeutic phages active against Escherichia coli (E. coli) and compare the efficacy with commercial Intesti bacteriophage on the extended-spectrum beta-lactamase (ESBL) positive E. coli (ESBL-EC) and performed the effectiveness of bacteriophage using the Galleria mellonella (G. mellonella) larvae model. Intesti bacteriophage is a polyvalent bacteriophage-based drug. The isolated bacteriophages were obtained from the river and clinical isolates of E. coli were used for the enrichment of bacteriophage isolation. The phages were first screened based on plaque morphology and host ranges determined on clinical strains. The susceptibility of phages was determined against 50 clinical isolates of E. coli and eight different laboratory isolates using the spot test technique. E. coli lytic phage Ec_P6 was used to determine the therapeutic and preventive effects on the G. mellonella larvae model. The slides were prepared by G. mellonella hemolymph for cytologic examination, stained with May Grünwald Giemsa (MGG), and evaluated by light microscopy. The results of the activities revealed lytic spectra ranging from 24% to 97%. Overall strains were susceptible to one or more phages from the panel. It was proved that Intesti bacteriophage is very effective in a wide variety of strains of E. coli including test strains, also showed that isolated Ec_P6 phage is as effective as commercial phage. The best MOI of this phage was 0.01, and infectivity decreased above 60 °C. The results suggest that phage is stable at pH values ranging between 5.0 and 9.0. In vivo study was found that in E. coli infection to achieve a survival high rate the infected larvae should be after 2 h treated with 0.01 MOI phage (10 µL, 106 PFU/mL) and colistin doses (10 µL, 2.5 mg/kg). It also prevented infection, increasing the survival of the larvae compared to the untreated control group. Ec_P6 phage was found to have a potential for the treatment of E. coli infections.

Antifungal and Anti-Virulent Activity of Origanum majorana L. Essential Oil on Candida albicans and In Vivo Toxicity in the Galleria mellonella Larval Model.

The aim of this study was to investigate and compare in detail both the antifungal activity in vitro (with planktonic and biofilm-forming cells) and the essential oil composition (EOs) of naturally growing (OMN) and cultivated (OMC) samples of Origanum majorana L. (marjoram). The essential oil composition was analyzed using GC-MS. The major constituent of both EOs was carvacrol: 75.3% and 84%, respectively. Both essential oils showed high antifungal activity against clinically relevant Candida spp. with IC50 and IC90 less than or equal to 0.5 µg mL-1 and inhibition of biofilm with a concentration of 3.5 µg mL-1 or less. Cultivated marjoram oil showed higher anti-biofilm activity against C. albicans. In addition, OMC showed greater inhibition of germ-tube formation (inhibition by 83% in Spider media), the major virulence factor of C. albicans at a concentration of 0.125 µg mL-1. Both EOs modulated cell surface hydrophobicity (CSH), but OMN proved to be more active with a CSH% up to 58.41%. The efficacy of O. majorana EOs was also investigated using Galleria mellonella larvae as a model. It was observed that while the larvae of the control group infected with C. albicans (6.0 × 108 cells) and not receiving treatment died in the controls carried out after 24 h, all larvae in the infected treatment group survived at the end of the 96th hour. When the treatment group and the infected group were evaluated in terms of vital activities, it was found that the difference was statistically significant (p < 0.001). The infection of larvae with C. albicans and the effects of O. majorana EOs on the hemocytes of the model organism and the blastospores of C. albicans were evaluated by light microscopy on slides stained with Giemsa. Cytological examination in the treatment group revealed that C. albicans blastospores were phagocytosed and morphological changes occurred in hemocytes. Our results indicated that the essential oil of both samples showed strong antifungal activities against planktonic and biofilm-forming C. albicans cells and also had an influence on putative virulence factors (germ-tube formation and its length and on CSH).

The Retrospective Analysis and the Demographics of Upper Extremity Injury Patients and Their Problems in the First 24 Hours After Operation.

OBJECTIVES: In this study, we analyzed patients with upper extremity injuries concerning patient demographics, injury type and etiological factors, and the most common problems encountered during the first 24 hours that were noted in the retrospective analysis. METHODS: In this study, a total of 82 patients who presented to the emergency plastic surgery clinic in Sisli Hamidiye Etfal Research and Training Hospital, postoperatively these patients were checked after surgery for first 24 hours concerning pain, nausea and vomiting, edema, agitation, arm immobilization arm and vascular patency. RESULTS: Among etiological factors, 54 patients were sharp-object trauma, 10 patients punched a hard object, 15 patients had work hazard, two patients had traffic accident, one patient from the fight. When these patients were postoperatively analyzed, in 45% patients pain, in 7% nausea and in 14 % bleeding were observed. Plaster was placed in 100% of the patients in order and their arms were elevated to reduce edema. During the first four hours, in 2% of the patients, edema was seen, 16% agitation, 8%vascular problems. CONCLUSION: When the type of injury is subcategorized to injuries of several compartments (nerve, tendon, muscle, artery, vein), the early postoperative challanges are more easily and correctly handled.

Mycoplasma hominis profile in women: Culture, kit, molecular diagnosis, antimicrobial resistance, and treatment.

OBJECTIVES: Mycoplasma hominis (M.hominis) infections are sexually transmitted and usually associated with urogenital and respiratory diseases. The aim of our study was to (i) detect M. hominis in the vaginal and urine samples of sexually active women using three different detection methods and (ii) to determine the antimicrobial susceptibility and recurrence after the treatment. METHODS: Both vaginal and urine samples were collected from 110 sexually active women at the Obstetrics and Gynecology Clinic, Baskent University Ankara Hospital, Turkey, between March 2015 and February 2016. The presence of M. hominis in the vaginal and urine samples was detected by in vitro culture, two biochemical diagnostics kits (Mycoplasma IES (Autobio, China) and Mycoplasma IST-2 (BioMérieux, France) and PCR. The antibiotic susceptibility of each sample was tested using the kits. The women positive for M. hominis were treated either singly or along with their sexual partners by tetracycline. RESULTS: M. hominis was detected in 72 of 220 (32.7%) samples (both vaginal and urine). Of which 37 showed contrary results with two different kits and then were confirmed by PCR. In 13 samples the IES kit identified M. hominis missed by IST-2, and in 8 samples the MIST-2 kit identified M. hominis missed by IES, while both kits missed 6 samples that were agar culture positive for M. hominis." The highest susceptibility rate was observed against pristinamycin (100%), followed by 91%, 83%, and 75% for doxycycline, tetracycline, and josamycin, respectively. Twenty-five patients treated with tetracycline were followed after one month. The recurrence of M. hominis was not observed in any of the 18 cases where both sexual partners were treated but recurred in 5 of the 7 singly treated women. CONCLUSIONS: The rate of M. hominis detection was significantly higher in the vaginal samples compared to the urine samples. The probability of detecting M. hominis by IST-2 kit was 1.18 times less than IES kit (p < 0.001). When the relationship between the samples was examined, the difference between IES and IST-2 for detecting M. hominis was statistically significant (p < 0.01). Antibiotic susceptibility tests indicated that the tetracycline group of antibiotics was effective in eliminating M. hominis when given to both the sexual partners.

Performance of CarbaNP and CIM tests in OXA-48 carbapenemase-producing Enterobacteriaceae.

This study applied two phenotypic tests, namely "Carbapenemase Nordmann-Poirel" (CarbaNP) test and "Carbapenem Inactivation Method" (CIM), against the isolates carrying the carbapenem resistance genes. The study included 83 carbapenem-resistant Enterobacteriaceae isolates producing oxacillinase-48 (OXA-48) and 30 carbapenem-sensitive Enterobacteriaceae isolates. Out of the total isolates studied, 77 isolates (92.77%) were identified as Klebsiella pneumoniae and six isolates (7.23%) were identified as Escherichia coli by Matrix Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry. Polymerase chain reaction (PCR) method used to detect resistance genes found that 74 isolates (89.16%) produced OXA-48 carbapenemase, whereas nine isolates (10.84%) produced both OXA-48 and New Delhi metallo-beta-lactamase-1 (NDM-1). The isolates producing both OXA-48 and NDM-1 were found to be positive by both phenotypic tests. Among isolates carrying only blaOXA-48 gene alone, nine isolates (13.04%) for CarbaNP test and two isolates for CIM test (2.90%) displayed false negative results, respectively. The sensitivity of CarbaNP and CIM tests was found to be 89.16% and 97.59%, respectively, whereas the specificity was determined to be 100% for both tests. These findings suggest that CarbaNP and CIM tests are useful tools to identify the carbapenemase producers. Molecular methods like PCR are recommended to verify false negative tests predicted to have OXA-48 activity.