Formulation of silymarin surface modified vesicles: In vitro characterization to cell viability assessment.

Silymarin (SLR) is a poorly water-soluble bioactive compound with a wide range of therapeutic activities. Nanosized silymarin vesicles (F1-F6) were prepared by the solvent evaporation rehydration method. The silymarin vesicles were evaluated for vesicle size, surface charge, entrapment efficiency, and drug release studies. The optimized SLR lipid vesicle (F3) was further modified with the addition of the cationic polymer chitosan. After that, the modified vesicle (F3C1) was assessed for permeation flux, antimicrobial activity, cell viability, and molecular docking studies. The silymarin vesicles showed nanometric size (<250 nm), low polydispersibility index (<0.05), negative surface charge, and high SLR entrapment (85-95 %). The drug release study result demonstrated a maximum drug release of 91.2 ± 2.8 %. After adding chitosan to the surface, there was a significant change in the size, polydispersibility index, surface charge (positive), and encapsulation efficiency. The drug release was found to be prolonged, and the permeation flux was also increased in comparison to free SLR. A comparative antimicrobial result was observed in comparison to the free SLR and standard drug. The cell viability assay also demonstrated a low IC50 value for F3C1 against the cell line.

Synthesis of (R)-(6-Methoxyquinolin-4-yl)[(1S,2S,4S,5R)-5-vinylquinuclidin-2-yl]methanol Tetraphenylborate Ion-Pair Complex: Characterization, Antimicrobial, and Computational Study.

The (R)-(6-Methoxyquinolin-4-yl)[(1S,2S,4S,5R)-5-vinylquinuclidin-2-yl]methanol (quinine)-tetraphenylborate complex was synthesized by reacting sodium tetraphenyl borate with quinine in deionized water at room temperature through an ion-pair reaction (green chemistry) at room temperature. The solid complex was characterized by several physicochemical methods. The formation of ion-pair complex between bio-active molecules and/or organic molecules is crucial to comprehending the relationships between bioactive molecules and receptor interactions. The complex under study was examined for antimicrobial activity. All theoretical calculations were carried out in vacuum and water using the B3LYP level 6-311G(d,p) levels of theory. The theoretical computation allowed for the prediction and visualization of ionic interactions, which explained the complex's stability. The results of energy optimization showed that the Q-TPB complex is stable with a negative complexation energy. The obtained geometries showed that the boron (B-) and nitrogen (N+) in piperidine of the two molecules tetraphenylborate and quinine are close to each other, which makes it possible for ions to interact. The modest energy gap between HOMO and LUMO showed that the compound was stable. The computation of the electron transitions of the two models by density functional theory (TD-DFT) in the solvent at the theoretical level B3LYP/6-311G(d,p) allowed for the detection of three UV/visible absorption bands for both models and the discovery of a charge transfer between the host and the guest. The UV absorption, infrared, and H NMR are comparable with the experimental part.

Synthesis of 4-Amino-N-[2 (diethylamino)Ethyl]Benzamide Tetraphenylborate Ion-Associate Complex: Characterization, Antibacterial and Computational Study.

The 4-amino-N-[2 (diethylamino) ethyl] benzamide (procainamide)-tetraphenylborate complex was synthesized by reacting sodium tetraphenyl borate with 4-amino-N-[2 (diethylamino) ethyl] benzamide, chloride salt, and procainamide in deionized water at room temperature through an ion-associate reaction (green chemistry) at room temperature, and characterized by several physicochemical methods. The formation of ion-associate complex between bio-active molecules and/or organic molecules is crucial to comprehending the relationships between bioactive molecules and receptor interactions. The solid complex was characterized by infrared spectra, NMR, elemental analysis, and mass spectrometry, indicating the formation of ion-associate or ion-pair complex. The complex under study was examined for antibacterial activity. The ground state electronic characteristics of the S1 and S2 complex configurations were computed using the density functional theory (DFT) approach, using B3LYP level 6-311 G(d,p) basis sets. R2 = 0.9765 and 0.9556, respectively, indicate a strong correlation between the observed and theoretical 1H-NMR, and the relative error of vibrational frequencies for both configurations was acceptable, as well. HOMO and LUMO frontier molecular orbitals and molecular electrostatics using the optimized were used to obtain a potential map of the chemical. The n → π* UV absorption peak of the UV cutoff edge was detected for both configurations of the complex. Spectroscopic methods were structures used to characterize the structure (FT-IR and 1HNMR). In the ground state, DFT/B3LYP/6-311G(d,p) basis sets were used to determine the electrical and geometric properties of the S1 and S2 configurations of the title complex. Comparing the observed and calculated values for the S1 and S2 forms, the HOMO-LUMO energy gap of compounds was 3182 and 3231 eV, respectively. The small energy gap between HOMO and LUMO indicated that the compound was stable. In addition, the MEP reveals that positive potential sites were around the PR molecule, whereas negative potential sites were surrounding the TPB site of atoms. The UV absorption of both arrangements is comparable to the experimental UV spectrum.

Benzo[g]quinazolines as antifungal against candidiasis: Screening, molecular docking, and QSAR investigations.

Candida albicans, an opportunistic pathogen, is the most common type of fungus and represents a substantial source of human invasive disease (nosocomial infection). This category of fungi are part of our microbiota, and given the appropriate environmental conditions, it has the potential to cause both superficial and systemic infections. There is a soaring resistance against the available anticandidal agents. The purpose of this research is to investigate the activity of certain previously synthesized benzo[g]quinazolines against C. albicans in vitro by using the cup-plate diffusion method. There was a marked difference in the effectiveness of the target compounds 1-6 against the sample of C. albicans that was tested. Benzo[g]quinazolines 1 (inhibition zone = 20 mm) and 2 (inhibition zone = 22 mm) had good effects in comparison to fluconazole (inhibition zone = 26 mm). A docking study was conducted between benzo[g]quinazolines 1-6 and Candida spp. CYP51 to establish the binding mode compared with fluconazole and VT-1161 (oteseconazole) as reference medicines, and it was determined that binding at the active site of Candida spp. CYP51 occurred in the same manner. Quantitative structure-activity relationship (QSAR) investigation was performed to further characterize the identified anticandidal agents and recognize the major regulatory components governing such activity. In future studies, the benzo[g]quinazoline scaffold could serve as a model for the design and development of novel derivatives with antifungal potential.

Carbonic Anhydrase Inhibition Activities of Schiff's Bases Based on Quinazoline-Linked Benzenesulfonamide.

Human carbonic anhydrase (CA, EC 4.2.1.1) (hCA) isoforms I, II, IX, and XII were investigated for their inhibitory activity with a series of new Schiff's bases based on quinazoline scaffold 4-27. The hCA I isoform was efficiently inhibited by Schiff's bases 4-6, 10-19, 22-27 and had an inhibition constant (Ki) value of 52.8-991.7 nM compared with AAZ (Ki, 250 nM). Amongst the quinazoline derivatives, the compounds 2, 3, 4, 10, 11, 16, 18, 24, 26, and 27 were proven to be effective hCA II inhibitors, with Ki values of 10.8-52.6 nM, measuring up to AAZ (Ki, 12 nM). Compounds 2-27 revealed compelling hCA IX inhibitory interest with Ki values of 10.5-99.6 nM, rivaling AAZ (Ki, 25.0 nM). Quinazoline derivatives 3, 10, 11, 13, 15-19, and 24 possessed potent hCA XII inhibitory activities with KI values of 5.4-25.5 nM vs. 5.7 nM of AAZ. Schiff's bases 7, 8, 9, and 21 represented attractive antitumor hCA IX carbonic anhydrase inhibitors (CAIs) with KI rates (22.0, 34.8, 49.2, and 45.3 nM, respectively). Compounds 5, 7, 8, 9, 14, 18, 19, and 21 showed hCA I inhibitors on hCA IX with a selectivity index of 22.46-107, while derivatives 12, 14, and 18 showed selective hCA I inhibitors on hCA XII with a selectivity profile of 45.04-58.58, in contrast to AAZ (SI, 10.0 and 43.86). Compounds 2, 5, 7-14, 19-23, and 25 showed a selectivity profile for hCA II inhibitors over hCA IX with a selectivity index of 2.02-19.67, whereas derivatives 5, 7, 8, 13, 14, 15, 17, 20, 21, and 22 showed selective hCA II inhibitors on hCA XII with a selectivity profile of 4.84-26.60 balanced to AAZ (SI, 0.48 and 2.10).

Clinical Efficacy of Single Use of Three Different Mouthrinses on the Level of Streptococcus mutans in Saliva.

AIM AND OBJECTIVE: The aim of this cross-sectional population-based clinical study was to assess the effect of single use of three different mouthrinses on the level of salivary Streptococcus mutans of 8 to 10-year-old Saudi children. MATERIALS AND METHODS: Convenient samples of 52 Saudi children aged 8-10 years were randomly allocated into four groups of 13 each. Saliva samples were collected to assess the level of S. mutans at baseline before rinsing with the assigned mouthrinse or control. Three mouthrinses, Avalon Avohex, Listerine Miswak, and Optima Aloe Dent Mouthrinse, were randomly distributed to the children. Each participant was instructed to rinse for 2 minutes using 10 mL of the assigned mouthrinse. Saliva samples were collected after rinsing and colony forming unit (CFU) of S. mutans per mL of saliva was calculated. Statistical analysis was performed to compare S. mutans count at baselines and postintervention values of each experimental group and control using paired t-test and one-way ANOVA. All statistical analyses were set at a significance level of p < 0.05. RESULTS: All test groups showed a reduction in salivary S. mutans compared to that at baseline. Statistically significant reduction (p > 0.05) in bacterial count was seen in Avalon Avohex group. CONCLUSION: A single-time rinse of chlorhexidine extract mouthrinse for 2 minutes effectively reduced the number of S. mutans of 8 to 10-year-old Saudi children. CLINICAL SIGNIFICANCE: Rinsing with chlorhexidine extract mouthrinse should be considered as a potential method in prevention of dental caries in children.

Genetic diversity of carbapenem-resistant Klebsiella Pneumoniae causing neonatal sepsis in intensive care unit, Cairo, Egypt.

Neonatal sepsis is a great challenge for clinicians and infection control practitioners, especially in facilities with limited resources. Carbapenem-resistant Klebsiella pneumoniae (CRKP) is rapidly increasing and carriages a major threat to neonates. We aimed to examine phenotypes causing neonatal late onset sepsis (NLOS) in comparison with neonatal early onset sepsis (NEOS) with further investigations of genotypes, and genetic relatedness of CRKP in neonatal late-onset sepsis. Our study included 88 neonates diagnosed with sepsis: 58 with (NLOS) and 30 with (NEOS) from November 2015 to April 2016, at neonatal intensive care unit (NICU) of Cairo University Hospital. K. pneumoniae was the most common encountered pathogen in the NLOS group (37.9%) with a mean sepsis score of 6.39 when compared to the NEOS group (p < 0.05). In Klebsiella group, C-reactive protein and interleukin-6 levels were significantly high (p ˂ 0.001) and 56.5% of the isolates were meropenem resistant. The most prevalent carbapenemase gene was OXA-48 which was identified in 14/23 (60.8%) followed by NDM-1 which was identified in 12/23 (52.2%) as detected by multiplex PCR. Coexistence of both carbapenemases was found in 52.2% (12/23). The blaKPC, blaIMP, and blaVIM genes were not harbored in the isolates. By investigating the genetic relatedness of CRKP by pulsed-field gel electrophoresis, 23 isolates of K. pneumoniae revealed various pulsed-field gel electrophoresis (PFGE) patterns, demonstrating that the isolates were non-clonal. Awareness of the existing phenotypes and genotypes is important for proper treatment and infection control practices.

Emergence of colistin resistance in multidrug-resistant Klebsiella pneumoniae and Escherichia coli strains isolated from cancer patients.

BACKGROUND: Colistin resistance is mainly driven by alterations in the Gram-negative outer membrane lipopolysaccharides and is caused, in most cases, by mutations in mgrB gene. However, the recent emergence of plasmid-encoded colistin resistance among Enterobacteriaceae strains represents a serious threat to global public health. In this paper we have investigated the rates of colistin resistance and the underlying mechanisms in 450 Klebsiella pneumoniae and Escherichia coli isolates obtained from cancer patients in Egypt. METHODS: Colistin susceptibility and minimum inhibitory concentrations were determined according to the European Committee on Antimicrobial Susceptibility Testing, by broth microdilution, and by E-test. The mcr-1, mcr-2 and mgrB genes were detected by PCR and then sequenced. Clonal diversity in colistin-resistant K. pneumoniae was evaluated by multilocus sequence typing. RESULTS: Forty (8.8%) colistin-resistant isolates, including 22 K. pneumoniae and 18 E. coli, were isolated over 18 months. Of these, 50% were carbapenem-resistant, out of which nine were blaOXA-48 and seven blaNDM-1 positive. The mechanisms of colistin resistance could be revealed only in three of the 40 resistant strains, being represented by mcr-1 in one blaNDM-1-positive E. coli strain and in one K. pneumoniae ST11 and by mgrB mutations, detected in one K. pneumoniae isolate. None of the studied isolates harbored mcr-2. CONCLUSIONS: Our results demonstrate a high frequency of colistin resistance in enterobacterial strains isolated from cancer patients, but a low prevalence of the most well known resistance mechanisms.

Synthesis and Spectroscopic Identification of Certain Imidazole-Semicarbazone Conjugates Bearing Benzodioxole Moieties: New Antifungal Agents.

During the last three decades the extent of life-threatening fungal infections has increased remarkably worldwide. Synthesis and structure elucidation of certain imidazole-semicarbazone conjugates 5a⁻o are reported. Single crystal X-ray analysis of compound 5e unequivocally confirmed its assigned chemical structure and the (E)-configuration of its imine double bond. Compound 5e crystallized in the triclinic system, P-1, a = 6.3561 (3) Å, b = 12.5095 (8) Å, c = 14.5411 (9) Å, α = 67.073 (4)°, ß = 79.989 (4)°, γ =84.370 (4)°, V = 1048.05 (11) ų, Z = 2. In addition, DIZ and MIC assays were used to examine the in vitro antifungal activity of the title conjugates 5a⁻o against four fungal strains. Compound 5e, bearing a 4-ethoxyphenyl fragment, showed the best MIC value (0.304 µmol/mL) against both C. tropicalis and C. parapsilosis species, while compounds 5c (MIC = 0.311 µmol/mL), 5k, and 5l (MIC = 0.287 µmol/mL) exhibited the best anti-C. albicans activity.

Evaluation of wound healing activity of henna, pomegranate and myrrh herbal ointment blend.

This study assessed the wound healing potential and antimicrobial activity of henna, pomegranate and myrrh extract formulations and their blend in excision, and dead space wound models in rats in comparison to a marketed ointment (gentamycin). The natural extracts were used in ointment formulations alone or in a combination of three extracts at a total concentration of 15% w/w in medications. The percent of wound contraction in case of henna, myrrh, pomegranate, the blend and gentamycin (10 mg/kg) were 85.90-98.5%, 88.35-99.52%, 93.55-100%, 97.30-100%, and 90.25-100% from days 16 to 20, respectively. The blended formulation showed the highest increase in the percent of wound contraction and decrease in the epithelisation period compared to other formulations and showed comparable results to the standard ointment. The histological studies of excision biopsy at day 24 showed healed skin structures with normal epithelisation, the restoration of adnexa and fibrosis within the dermis in all of the formulation- and gentamycin-treated groups while the control group lagged behind in the formation of the amount of ground substance in the granulation tissue. The formulations showed antimicrobial activity against Candida, Staphylococcus aureus, mucous membrane infections and E. coli topical infections. The study proved the wound healing potential and antimicrobial activity of the herbal extract.

The emergence of a novel sequence type of MDR Acinetobacter baumannii from the intensive care unit of an Egyptian tertiary care hospital.

BACKGROUND AND AIM OF WORK: Acinetobacter baumannii is known for nosocomial outbreaks worldwide. In this study, we aimed to investigate the antibiotic susceptibility patterns and the clonal relationship of A. baumannii isolates from the intensive care unit (ICU) of an Egyptian hospital. METHODS: In the present study, 50 clinical isolates of multidrug resistant (MDR)-A. baumannii were obtained from patients admitted into the ICU from June to December 2015. All isolates were analyzed for antimicrobial susceptibilities. Multiplex PCR was performed to detect genes encoding oxacillinase genes (bla OXA-51-like, bla OXA-23-like, bla OXA-24-like, and bla OXA-58-like). Multilocus sequence typing (MLST) based on the seven-gene scheme (gltA, gyrB, gdhB, recA, cpn60, gpi, rpoD) was used to examine these isolates. RESULTS: All A. baumannii clinical isolates showed the same resistance pattern, characterized by resistance to most common antibiotics including imipenem (MIC ≥ 8µ/mL), with the only exception being colistin. Most isolates were positive for bla OXA-51-like and bla OXA-23-like (100 and 96%, respectively); however, bla OXA-24-like and bla OXA-58-like were not detected. MLST analysis identified different sequence types (ST195, ST208, ST231, ST441, ST499, and ST723) and a new sequence type (ST13929) with other sporadic strains. CONCLUSIONS: MDR A. baumannii strains harboring bla OXA-23-like genes were widely circulating in this ICU. MLST was a powerful tool for identifying and epidemiologically typing our strains. Strict infection control measures must be implemented to contain the worldwide spread of MDR A. baumannii in ICUs.

Synthesis, Single Crystal X-ray Analysis, and Antifungal Profiling of Certain New Oximino Ethers Bearing Imidazole Nuclei.

Fungal infections threaten human health, particularly in immune-compromised patients worldwide. Although there are a large number of antifungal agents available, the desired clinical attributes for the treatment of fungal infections have not yet been achieved. Azoles are the mainstay class of the clinically used antifungal agents. In the current study, the synthesis, spectroscopic characterization, and antifungal activity of certain new oximino ethers Va-n bearing imidazole nuclei are reported. The (E)-configuration of the imine double bond of the synthesized compounds Va-n has been confirmed via single crystal X-ray analysis of compound Vi as a representative example of this class of compounds. The molecular structure of compound Vi was crystallized in the monoclinic, P21/c, a = 18.7879(14) Å, b = 5.8944(4) Å, c = 16.7621(12) Å, ß = 93.063(3)°, V = 1855.5(2) ų, Z = 4. The in vitro antifungal activity of the synthesized compounds Va-n were evaluated using diameter of the inhibition zone (DIZ) and minimum inhibitory concentration (MIC) assays against different fungal strains. Compound Ve manifested anti-Candida albicans activity with an MIC value of 0.050 µmol/mL, being almost equipotent with the reference antifungal drug fluconazole (FLC),while compounds Vi and Vn are the most active congeners against Candida parapsilosis, being equipotent and about twenty-three times more potent than FLC with an MIC value of 0.002 µmol/mL. The results of the current report might support the development of new potent and safer antifungal azoles.

Synthesis, X-ray Single Crystal Structure, Molecular Docking and DFT Computations on N-[(1E)-1-(2H-1,3-Benzodioxol-5-yl)-3-(1H-imidazol-1-yl)propylidene]-hydroxylamine: A New Potential Antifungal Agent Precursor.

Mycoses are serious health problem, especially in immunocompromised individuals. A new imidazole-bearing compound containing an oxime functionality was synthesized and characterized with different spectroscopic techniques to be used for the preparation of new antifungal agents. The stereochemistry of the oxime double bond was unequivocally determined via the single crystal X-ray technique. The title compound 4, C13H13N3O3·C3H8O, crystallizes in the monoclinic space group P21with a = 9.0963(3) Å, b = 14.7244(6) Å, c = 10.7035(4) Å, ß = 94.298 (3)°, V = 1429.57(9) ų, Z = 2. The molecules were packed in the crystal structure by eight intermolecular hydrogen bond interactions. A comprehensive spectral analysis of the title molecule 4 has been performed based on the scaled quantum mechanical (SQM) force field obtained by density-functional theory (DFT) calculations. A molecular docking study illustrated the binding mode of the title compound 4 into its target protein. The preliminary antifungal activity of the title compound 4 was determined using a broth microdilution assay.

Synthesis, antitumor and antimicrobial activity of some new 6-methyl-3-phenyl-4(3H)-quinazolinone analogues: in silico studies.

Some new derivatives of substituted-4(3H)-quinazolinones were synthesized and evaluated for their in vitro antitumor and antimicrobial activities. The results of this study demonstrated that compound 5 yielded selective activities toward NSC Lung Cancer EKVX cell line, Colon Cancer HCT-15 cell line and Breast Cancer MDA-MB-231/ATCC cell line, while NSC Lung Cancer EKVX cell line and CNS Cancer SF-295 cell line were sensitive to compound 8. Additionally, compounds 12 and 13 showed moderate effectiveness toward numerous cell lines belonging to different tumor subpanels. On the other hand, the results of antimicrobial screening revealed that compounds 1, 9 and 14 are the most active against Staphylococcus aureus ATCC 29213 with minimum inhibitory concentration (MIC) of 16, 32 and 32 µg/mL respectively, while compound 14 possessed antimicrobial activities against all tested strains with the lowest MIC compared with other tested compounds. In silico study, ADME-Tox prediction and molecular docking methodology were used to study the antitumor activity and to identify the structural features required for antitumor activity.

Design, Synthesis, Antimicrobial Evaluation and Molecular Modeling Study of 1,2,4-Triazole-Based 4-Thiazolidinones.

A series of 3-(2H-1,2,4-triazol-5-yl)-1,3-thiazolidin-4-one derivatives (7c-l) was designed and synthesized. Their structures have been elucidated based on analytical and spectral data. They were evaluated for their antibacterial and antifungal activities. Compound 7h showed the highest activity against all tested strains, except P. vulgaris, with MIC 8 µg/mL and 4 µg/mL against S. aureus and C. albicans, respectively. Furthermore, Compounds 7c, 7h, and 7j demonstrated moderate anti-mycobacterium activity. The binding mode of the synthesized thiazolidinones to bacterial MurB enzyme was also studied. Good interactions between the docked compounds to the MurB active site were observed primarily with Asn83, Arg310, Arg188 and Ser82 amino acid residues.

Synthesis of Pyrazole-Thiobarbituric Acid Derivatives: Antimicrobial Activity and Docking Studies.

A one-pot reaction was described that results in various pyrazole-thiobarbituric acid derivatives as new pharmacophore agents. These new heterocycles were synthesized in high yields with a broad substrate scope under mild reaction conditions in water mediated by NHEt2. The molecular structures of the synthesized compounds were assigned based on different spectroscopic techniques. The new compounds were evaluated for their antibacterial and antifungal activity. Compounds 4h and 4l were the most active compounds against C. albicans with MIC = 4 µg/L. Compound 4c exhibited the best activity against S. aureus and E. faecalis with MIC = 16 µg/L. However, compounds 4l and 4o were the most active against B. subtilis with MIC = 16 µg/L. Molecular docking studies for the final compounds and standard drugs were performed using the OpenEye program.

Diversity of Molecular Mechanisms Conferring Carbapenem Resistance to Pseudomonas aeruginosa Isolates from Saudi Arabia.

Background. This study described various molecular and epidemiological characters determining antibiotic resistance patterns in Pseudomonas aeruginosa isolates. Methods. A total of 34 carbapenem-resistant P. aeruginosa clinical isolates were isolated from samples collected at a tertiary hospital in Riyadh, Saudi Arabia, from January to December 2011. Susceptibility testing, serotyping, molecular characterization of carbapenem resistance, and pulsed-field gel electrophoresis (PFGE) were performed. Results. All isolates were resistant to ceftazidime, and more than half were highly resistant (minimum inhibitory concentration (MIC) > 256 mg/L). Fifteen isolates had MIC values ≥64 mg/L for any of the carbapenems examined. Vietnamese extended-spectrum ß-lactamase (VEB-1) (n = 16/34) and oxacillinase (OXA-10) (n = 14/34) were the most prevalent extended-spectrum ß-lactamase and penicillinase, respectively. Verona imipenemase (VIM-1, VIM-2, VIM-4, VIM-11, and VIM-28) and imipenemase (IMP-7) variants were found in metallo-ß-lactamase producers. A decrease in outer membrane porin gene (oprD) expression was seen in nine isolates, and an increase in efflux pump gene (MexAB) expression was detected in five isolates. Six serotypes (O:1, O:4, O:7, O:10, O:11, and O:15) were found among the 34 isolates. The predominant serotype was O:11 (16 isolates), followed by O:15 (nine isolates). PFGE analysis of the 34 carbapenem-resistant P. aeruginosa isolates revealed 14 different pulsotypes. Conclusions. These results revealed diverse mechanisms conferring carbapenem resistance to P. aeruginosa isolates from Saudi Arabia.

The transferability of blaOXA-23 gene in multidrug-resistant Acinetobacter baumannii isolates from Saudi Arabia and Egypt.

Carbapenem-resistant Acinetobacter spp. have been increasingly reported worldwide including Saudi Arabia and Egypt. We examined 64, non-repetitive, Acinetobacter baumannii isolates collected in 2013 and 2014 from four different medical centres (two from Saudi Arabia and two from Egypt). All the isolates were resistant to ceftazidime and ciprofloxacin. The intI1 harbouring blaGES-11 and aac-6'-1b was detected in 19% (n=12) of the isolates. ISAba1 over-expression of blaADC gene was observed in 65% (n=42) of isolates. Of all the isolates 19% (n=12) had ISAba1 upstream of the blaOXA-51-like gene, 69% (n=44) carried the blaOXA-23 gene within the Tn2006 structure, 8% (n=5) had blaOXA-24-like gene and 9% (n=6) harboured either blaVIM-2 or blaNDM-1 gene. Eighty nine percent (n=57) of isolates were resistant to imipenem and had an MIC of ≥8mg/L. Pulsed-field gel electrophoresis (PFGE) typing revealed the presence of 23 different PFGE. Three PFGE types were very widespread, ST236 (CC104) (PFGE type 1, n=15), ST208 (CC92) (PFGE type 2, n=10), ST884 (CC unassigned) (PFGE type 3, n=7) in and across all four medical centres. The blaOXA-23 gene was found to be present on a 60kb transferable plasmid in both PFGE type 1 and 2 but was absent in PFGE type 3. This is the first study to report on the emergence of ST236 in Saudi Arabia and Egypt, and spread of distinct carbapenem resistant A. baumannii clones belonging to ST884, ST945 and ST1096 in Saudi Arabia.

Dissemination of VIM-2 producing Pseudomonas aeruginosa ST233 at tertiary care hospitals in Egypt.

BACKGROUND: Pseudomonas aeruginosa is an important nosocomial pathogen, commonly causing infections in immunocompromised patients. The aim of this study was to examine the genetic relatedness of metallo-beta-lactamase (MBL) producing carbapenem resistant Pseudomonas aeruginosa clinical isolates collected from 2 tertiary hospitals in Cairo, Egypt using Multi Locus sequence typing (MLST). METHODS: Phenotypic and genotypic detection of metallo-beta-lactamase for forty eight non-duplicate carbapenem resistant P. aeruginosa isolates were carried out. DNA sequencing and MLST were done. RESULTS: The bla VIM-2 gene was highly prevalent (28/33 strains, 85%) among 33 MBL-positive P.aeruginosa isolates. MLST revealed eleven distinct Sequence Types (STs). A unique ST233 clone producing VIM-2 was documented by MLST in P.aeruginosa strains isolated from Cairo university hospitals. The high prevalence of VIM-2 producers was not due to the spread of a single clone. CONCLUSIONS: The findings of the present study clearly demonstrate that clones of VIM-2 positive in our hospitals are different from those reported from European studies. Prevalence of VIM-2 producers of the same clone was detected from surgical specimens whereas oncology related specimens were showing diverse clones.

Molecular characteristics of extended-spectrum ß-lactamase-producing Escherichia coli in Riyadh: emergence of CTX-M-15-producing E. coli ST131.

BACKGROUND: The prevalence of extended-spectrum ß-lactamase-producing Escherichia coli (ESBL-EC) has increased recently. The aim of this study was to further characterise and to assess the occurrence of ESBL-EC in Riyadh, to use pulsed field gel electrophoresis (PFGE) typing to investigate the epidemiology of ESBL-EC and to determine the prevalence of ST131 in ESBL-EC. METHODS: A total of 152 E. coli isolates were collected at a tertiary hospital in Riyadh from September 2010 to June 2011. Genotypic and phenotypic methods were used to characterise ESBLs. PFGE was used to determine genetic relatedness. Detection of ST131 and CTX-M-like ESBLs was performed using real-time PCR. RESULTS: Of 152 strains, 31 were positive for ESBLs by phenotypic methods. The blaCTX-M-15 gene was highly prevalent (30/31 strains, 96.77%) among the 31 ESBL-positive E. coli strains. The blaCTX-M-27 gene was detected in one strain. Twenty (64.5%) out of 31 of ESBL-EC were ST131. PFGE revealed 29 different pulsotypes. CONCLUSIONS: Our study documented the high prevalence of ESBLs in E. coli isolates, with CTX-M-15 as the predominant ESBL gene. ST131 clone producing CTX-M-15 has a major presence in our hospital. The high prevalence of CTX-M producers was not due to the spread of a single clone. To the best of our knowledge, this study represents the first report of CTX-M-15 and CTX-M-27 ß-lactamases and the detection of the ST131 clone in Saudi E. coli isolates.