Investigation of Panton-Valentine Leukocidin Presence in the Clinical Strains of Staphylococcus aureus

Objective: In this study, the presence of Panton-Valentine Leukocidin (PVL) was investigated in the Staphylococcus aureus clinical isolates by PCR.Material and Methods: In this study, 130 MRSA and 20 methicillin-susceptible S. aureus (MSSA) isolates were tested among various clinical samples between February 2006 and June 2008. Confirmation of S. aureus isolates and the methicillin resistance of these isolates were made by multiplex PCR. The presence of PVL was tested by both multiplex PCR and single target PCR.Results: The presence of PVL was determined in 3 isolates. Two of the isolates were from MRSA isolates, one was from MSSA isolates. One of the PVL positive MRSA isolate was recovered from a wound specimen, the other was from blood culture. PVL positive MSSA isolate was recovered from an urine specimen. All of the three PVL positive isolates were resistant to tetracycline. One of the PVL positive MRSA isolates which was recovered from blood culture was resistant to gentamicin and ciprofloxacin, while the other PVL positive isolate was susceptible. Conclusion: Further studies are needed to determine the prevalence and genetic characteristics of PVL positive isolates and to prevent dissemination of PVL positive isolates both in the hospital environment and the community

Antimicrobial and antioxidant activity of the essential oil of the Turkish endemic species Achillea Phrygia Boiss. & Bal.

Ozkan, Gulcan/0000-0002-3333-7537;WOS: 000337670700006The essential oil obtained from the dried flowering aerial parts of Achillea phrygia Boiss & Bal. by hydrodistilation was analysed by gas chromotography-mass spectrometry. Camphor (35.55 %), 2-furaldehyde (16.59 %) and 1,8-cineol (eucalyptol) (10.12 %) were detected as the major components of the essential oil. Essential oil of the plant was also tested for antimicrobial activity using the disc-diffusion method against 6 reference bacterial strains and 65 clinical bacterial isolates. Essential oil of A. phrygia showed antimicrobial activity against methicillin-resistant Staphylococcus aureus (MRSA), methicillin-sensitive S. aureus (MSSA), Acinetobacter baumannii and bacterial strains as S. aureus ATCC 25923, S. aureus ATCC 43300, Acinetobacter baumannii ATCC 19606. in additionally, the essential oil were not effective against bacterial strains as Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922, Enterococcus faecalis ATCC 29212. Morover, the total antioxidant capacity and the scavenging effect on 2,2diphenil-1-picrylhydrazyl (DPPH) radicals of the essential oil were also evaluated. the radical scavenging activity of A. phrygia essential oil was 40.43 %.Research Funds of the University of Ondokuz Mayis, Samsun, TurkeyOndokuz Mayis UniversityThe authors are thankful to Prof. Dr. Sezai Ercisli for it's help regarding the antioxidant analysis. Financial support made by the Research Funds of the University of Ondokuz Mayis, Samsun, Turkey is gratefully acknowledged

Investigation of plasmid-mediated quinolone resistance in pseudomonas aeruginosa strains isolated from cystic fibrosis patients

Pseudomonas aeruginosa doğada yaygın olarak bulunan ve ciddi nozokomiyal enfeksiyonlara neden olan bir bakteridir. Birçok antibakteriyel ajana karşı intrensek dirence sahip olması nedeniyle P.aeruginosa ile oluşan enfeksiyonların tedavisinde zorluklar yaşanmaktadır. Kinolonlar, özellikle siprofloksasin, tedavide kullanılan önemli ajanlardandır. Ancak kinolonlara da direnç gelişmesi önemli bir sorundur. Kinolonlara direnç sıklıkla kromozomal mutasyon ve dışa-atım pompaları aracılığıyla olmaktadır. Son yıllarda Enterobacteriaceae ailesi üyelerinde plazmid aracılı kinolon direnci de saptanmış; bu dirence neden olan gen ailesi qnr olarak adlandırılmıştır. Ayrıca yine plazmid ile aktarılan ve aminoglikozid direnci ile birlikte kinolon direncine de neden olan aac(6’)-Ib-cr gen bölgesi de Enterobacteriaceae ailesine ait bakteriyel izolatlarda tespit edilmiştir. Yapılan sınırlı sayıdaki çalışmada, P.aeruginosa izolatlarında qnr gen bölgesinin varlığı ve aac(6’)-Ib-cr gen bölgesi henüz gösterilememiştir. Bu çalışmada, kistik fibrozisli olgulardan izole edilen P.aeruginosa suşlarında plazmid aracılı florokinolon direncinin araştırılması amaçlanmıştır. Çalışmaya, hastaların solunum yolu örneklerinden izole edilen 110 P.aeruginosa suşu dahil edilmiş ve izolatların siprofloksasin duyarlılıkları CLSI önerileri doğrultusunda Kirby-Bauer disk difüzyon yöntemiyle çalışılmıştır. Suşlarda qnrA, qnrB, qnrC, qnrS ve aac(6’)-Ib-cr gen bölgelerinin varlığı, bu bölgeler için özgül primer çiftleri kullanılarak multipleks polimeraz zincir reaksiyonu yöntemiyle araştırılmıştır. Çalışmada pozitif kontrol olarak Escherichia coli J53 pMG252 (qnrA1 pozitif), E.coli J53 pMG252 (qnrS1 pozitif), E.coli J53 pMG258 (qnrB1 ve aac(6’)-Ib-cr pozitif), Klebsiella pneumoniae ref.15 (qnrB pozitif), Enterobacter cloacae ref.287 (qnrS pozitif), E.coli ref.20 (qnrA pozitif) ve pHS11 plazmidinin (qnrC pozitif) konjugasyon yoluyla aktarıldığı E.coli DH10 suşu kullanılmıştır. P.aeruginosa klinik izolatlarının 13’ü siprofloksasine dirençli, yedisi orta duyarlı ve 90’ı duyarlı olarak bulunmuştur. Çalışma sonucunda test edilen toplam 110 P.aeruginosa izolatında hem qnr gen bölgesi hem de aac(6’)-Ib-cr gen bölgesi tespit edilememiştir. Bununla birlikte bu bulgunun daha çok klinik izolat içeren araştırmalarla desteklenmesi P.aeruginosa izolatlarında kinolon direncinin belirlenmesi ve önlenmesinde önemli olacaktır.Pseudomonas aeruginosa which is widely found in the environment, may lead to serious nosocomial infections. Due to its intrinsic resistance to many antibacterial agents, treatment of P.aeruginosa infections usually present difficulty. Quinolones, especially ciprofloxacin, are crutial antibiotics for the treatment of P.aeruginosa infections. However resistance developing to quinolones may become an important problem. Resistance to quinolones is often a result of chromosomal mutations and by the effect of efflux pumps. Recently plasmid-mediated quinolone resistance have been reportedin the members of Enterobacteriaceae family. The gene responsible for this resistance is called qnr. In addition to qnr genes there is also another gene called aac(6’)-Ib-cr responsible for plasmid-mediated quinolone resistance and aminoglycoside resistance. Limited studies which to screen P.aeruginosa strains for the presence of qnr gene region, revealed no positivity. The aim of this study was to investigate the plasmid-mediated quinolone resistance in P.aeruginosa strains isolated from cystic fibrosis patients. A total of 110 P.aeruginosa strains isolated from respiratory tract specimens from the patients were included in the study. Ciprofloxacin susceptibilities of the isolates were detected by Kirby-Bauer disk diffusion method according to CLSI guidelines. The presence of qnrA, qnrB, qnrC, qnrS and aac(6’)-Ib-cr genes were searched by multiplex polymerase chain reaction (PCR) with the use of specific individual primer pairs. As positive control strains, Escherichia coli J53 pMG252 (qnrA1 positive), E.coli J53 pMG252 (qnrS1 positive), E.coli J53 pMG258 (qnrB1 and aac(6’)-Ib-cr positive), Klebsiella pneumoniae ref.15 (qnrB positive), Enterobacter cloacae ref.287 (qnrS positive), E.coli ref.20 (qnrA positive) and E.coli DH10 conjugated with pHS11 plasmid (qnrC positive) were used. Of 110 P.aeruginosa clinical isolates, 13 were found resistant to ciprofloxacin, while 7 were intermediate. However multiplex PCR yielded no positivity in terms of qnrA, qnrB, qnrC, qnrS and aac(6’)-Ib-cr gene regions. In conclusion, although our results indicated that none of the tested P.aeruginosa strains harboured those genes, further multicenter studies with large numbers of isolates are needed to confirm these results

Cytotoxicity of Acrylic Resins, Particulate Filler Composite Resin and Thermoplastic Material in Artificial Saliva with and without Melatonin

There is limited information on the effect of melatonin on the cytotoxicity of dental materials. The study evaluated the cytotoxic effects of heat- and auto-polymerized acrylic resin, particulate filler composite resin and a thermoplastic material on L-929 fibroblast cell viability at different incubation periods in artificial saliva without and with melatonin. Disk-shaped specimens were prepared according to each manufacturer's instructions and divided into two groups to be stored either in artificial saliva (AS) and AS with melatonin (ASM). The measurements were performed using an MTT (3-(4,5)-dimethylthiazol-2-yl)-2,5-diphenyl tetrazoliumbromide) assay, in which the L-929 mouse fibroblasts cell culture was used. For the MTT test, extracts were examined at 1, 24, 72 h and 1 and 2 weeks. Data were analyzed using 3-way ANOVA and Tukey's tests. No significant difference was found between groups AS and ASM (F = 0.796; p = 0.373). Incubation period significantly affected all materials tested (p < 0.001). Storing resin-based materials in artificial saliva with melatonin solution for 24 h may reduce cytotoxic effects on the fibroblast cells for which the highest effect was observed. Soaking resin prosthesis or orthodontic appliances in artificial saliva with melatonin at least 24 h before intraoral use or rinsing medium containing melatonin may be recommended for decreasing the cytotoxicity of dental resin materials

Cytotoxicity of Acrylic Resins, Particulate Filler Composite Resin and Thermoplastic Material in Artificial Saliva with and without Melatonin

There is limited information on the effect of melatonin on the cytotoxicity of dental materials. The study evaluated the cytotoxic effects of heat- and auto-polymerized acrylic resin, particulate filler composite resin and a thermoplastic material on L-929 fibroblast cell viability at different incubation periods in artificial saliva without and with melatonin. Disk-shaped specimens were prepared according to each manufacturer&rsquo;s instructions and divided into two groups to be stored either in artificial saliva (AS) and AS with melatonin (ASM). The measurements were performed using an MTT (3-(4,5)-dimethylthiazol-2-yl)-2,5-diphenyl tetrazoliumbromide) assay, in which the L-929 mouse fibroblasts cell culture was used. For the MTT test, extracts were examined at 1, 24, 72 h and 1 and 2 weeks. Data were analyzed using 3-way ANOVA and Tukey&rsquo;s tests. No significant difference was found between groups AS and ASM (F = 0.796; p = 0.373). Incubation period significantly affected all materials tested (p &lt; 0.001). Storing resin-based materials in artificial saliva with melatonin solution for 24 h may reduce cytotoxic effects on the fibroblast cells for which the highest effect was observed. Soaking resin prosthesis or orthodontic appliances in artificial saliva with melatonin at least 24 h before intraoral use or rinsing medium containing melatonin may be recommended for decreasing the cytotoxicity of dental resin materials

Phenotypic and molecular characterization of Yersinia ruckeri isolates from Rainbow Trout (Oncorhynchus mykiss, Walbaum, 1792) in Turkey

The aim of the study was the phenotypic and molecular characterization of Yersinia (Y.) ruckeri strains, the causative agent of Enteric Red mouth Disease (ERM), by antibiotyping, random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) and sodium dodecylsulphate-polyacrylamide gel electrophoresis (SDS-PAGE) patterns of whole cell proteins. For this aim, a total of 97 Y ruckeri isolates were analyzed. The isolates were distinguished into ten antibiotypes and six phenotypes according to their resistance properties and whole cell protein profiles, respectively. Also, a glycoprotein band of approximately 25.5 kDa was observed in all Y ruckeri strains tested. In all strains, six different RAPD types were observed. In conclusion, Y ruckeri strains isolated from rainbow trout of fish farms in Turkey showed variation according to their phenotypic and genotypic characteristics, and the use of these three typing techniques in double and triple combinations could be more useful for discriminating the strains

In vitro effect of ankaferd blood stopper®, a plant extract against Mycobacterium tuberculosis isolates

Dirençli Mycobacterium tuberculosis enfeksiyonlarının tedavisi, toksik yan etkileri olan antitüberküloz ilaçların kombinasyonunu gerektirdiğinden, güvenli ve etkili yeni ilaçlara gereksinim vardır. Alpinia officinarum, Glycyrrhiza glabra, Thymus vulgaris, Urtica dioica ve Vitis vinifera bitki ekstrelerinin bir karışımı olan Ankaferd Blood Stopper® (ABS), homeostatik ve antibakteriyel etkilere sahiptir. Ülkemizde ABS’nin standart solüsyonları, travmatik veya cerrahi sonrası kanama kontrolü amacıyla topikal olarak kullanılmaktadır. Bu çalışmada, M.tuberculosis izolatlarına karşı ABS’nin in vitro antitüberküloz etkinliğinin araştırılması amaçlanmıştır. Çalışmaya, 57 klinik izolat [17’si çok ilaca dirençli (ÇİD), biri izoniazid (INH) ve streptomisin (STR)’e dirençli, 11’i sadece INH’e dirençli, ikisi sadece STR’e dirençli, ikisi sadece etambutol (ETM)’e dirençli, 24’ü bütün ilaçlara duyarlı] ve üç standart suş [H37Rv (bütün ilaçlara duyarlı), ATCC 35822 (INH’e dirençli), ATCC 35820 (STR’e dirençli)] dahil edilmiştir. ABS MİK değerleri agar dilüsyon yöntemi kullanılarak tespit edilmiştir. Çalışmamızda, bütün ilaçlara duyarlı M.tuberculosis H37Rv suşu için ABS MİK değeri 10.94 ?g/ml olarak belirlenirken, INH dirençli ATCC 35822 ve STR dirençli ATCC 35820 suşları için 21.88 ?g/ml olarak saptanmıştır. Klinik izolatlar dikkate alındığında; duyarlı 24 suşun 17’sinde ABS MİK değeri 10.94 ?g/ml, altısında 21.88 ?g/ml ve birinde < 1.37 ?g/ml; ÇİD 17 suşun ise birinde 5.47 ?g/ml, beşinde 10.94 ?g/ml ve 11’inde 21.88 ?g/ml olarak bulunmuştur. Sadece INH direnci olan 11 izolatın MİK değerleri < 1.37-21.88 ?g/ml arasında değişiklik göstermiştir. Yalnızca STR’ye dirençli iki izolatın MİK değerleri 21.88 ?g/ml; yalnızca ETM’e dirençli iki izolatın MİK değerleri de 21.88 ?g/ml ve 10.94 ?g/ml olarak saptanmıştır. Hem INH hem de STR direnci olan bir izolatın MİK değeri ise 21.88 ?g/ml olarak izlenmiştir. Test edilen bakterilerin MİK50 ve MİK90 değerleri sırasıyla 10.94 ?g/ml ve 21.88 ?g/ml olarak tespit edilmiştir. Sonuç olarak çalışmamızda, ABS’nin topikal olarak kullanılan solüsyonunun yaklaşık 16 kat dilüe edilmiş konsantrasyonu, tüberküloz basillerine karşı in vitro olarak etkili bulunmuş ve bu sonuç ABS’nin kütanöz tüberkülozda, özellikle ÇİD M.tuberculosis’in neden olduğu osteomiyelit ve lenfadenit gibi tüberküloz odaklarının cerrahi debridmanında antitüberküloz ilaçlarla birlikte destekleyici amaçla başarıyla kullanılabileceğini düşündürmüştür.Treatment of drug-resistant Mycobacterium tuberculosis infections requires combination of anti-tuberculosis drugs which have several toxic side effects. Thus there is a need for safer and effective new drugs. Ankaferd Blood Stopper&reg; (ABS), which is a mixture of plant extracts prepared from Alpinia officinarum, Glycyrrhiza glabra, Thymus vulgaris, Urtica dioica and Vitis vinifera, has homeostatic and antibacterial effects. Standard solutions of ABS are already being used topically for post-traumatic and post-operative bleeding control in our country. This study was aimed to evaluate the in vitro activity of ABS against M.tuberculosis isolates. A total of 57 clinical isolates [17 multidrug resistant (MDR), 11 resistant to only isoniazid (INH), one resistant to INH and streptomycin (STR), two resistant only to STR, two resistant only to ETM, and 24 susceptible to all drugs] and three standard strains [H37Rv (susceptible to all drugs), ATCC 35822 (INH-resistant), ATCC 35820 (STR-resistant)] were included in the study. Agar dilution method was used to detect the MIC values of ABS. In the study, ABS MIC value was determined as 10.94 &amp;#956;g/ml for M.tuberculosis H37Rv strain which was susceptible to all antituberculosis drugs, whereas it was determined as 21.88 &amp;#956;g/ml for INH-resistant ATCC 35822 and STRresistant ATCC 35820 strains. The MIC values for 24 susceptible clinical isolates were as follows; 10.94 &amp;#956;g/ml (n= 17), 21.88 &amp;#956;g/ml (n= 6) and &lt; 1.37 &amp;#956;g/ml (n= 1). When evaluating 17 MDR clinical isolates, MIC values were determined as 5.47 &amp;#956;g/ml (n= 1), 10.94 &amp;#956;g/ml (n= 5) and 21.88 &amp;#956;g/ml (n= 11). MIC values were ranging between &lt; 1.37-21.88 &amp;#956;g/ml among 11 INH-resistant isolates. These isolates were susceptible to other first line anti-tuberculosis drugs. MIC value of one isolate resistant to both of INH and STR was determined as 21.88 &amp;#956;g/ml. MIC value of the two sole STR-resistant isolates was 21.88 &amp;#956;g/ml. MIC values of the two sole ETM-resistant isolates were determined as 21.88 &amp;#956;g/ml and 10.94 &amp;#956;g/ml. MIC50 and MIC90 values for the tested bacteria were 10.94 &amp;#956;g/ml and 21.88 &amp;#956;g/ml, respectively. It was concluded that 16 fold diluted concentration of the topically used ABS solution was found to be active against tuberculosis bacilli in vitro. Thus ABS might be used as a supportive agent together with anti-tuberculous drugs during debridement of multiple drug-resistant M.tuberculosis caused osteomyelitis and lymphadenitis lesions

Detection of the First QnrS Gene Positivity in Aquatic Aeromonas spp. Isolates in Turkey

WOS: 000350946600012PubMed: 25706737Aeromonas spp. are oxidase positive, gram-negative, facultative anaerobic bacilli that are widely distributed in aquatic environments. A.hydrophila, A.sobria and A.bestiarum may cause severe infections in both human and cold-blooded animals. Environmental persistance of quinolones that are widely used in both human and veterinary medicine plays an important role in the selection of resistant mutants. Plasm id-mediated resistance is one of the main mechanisms involved in quinolone resistance, and qnr, qepA, aac(6')-Ib-cr, oqxAB genes are identified as resistance determinants. Determination of various types of qnr gene in different bacteria mainly in Enterobacteriaceae, suggests that they are widely distributed in nature. Recently, plasmid-mediated quinolone resistance was defined among Aeromonas species isolated from water. the aim of this study was to investigate the presence of qnr genes among aquatic Aeromonas spp. in Turkey. A total of 45 Aeromonas strains isolated from water and fishes collected from three different geographical regions (Aegean, Mediterranean and Blacicsea) in Turkey, were included in the study. the isolates were identified at species level by the use of 16S rDNA-RFLP (Restriction fragment length polymorphism) analysis and multiplex polymerase chain reaction (M-PCR). Among the isolates, 20 were identified as A.sobria, 10 as A.hydrophila, nine as A.salmonicida, four as A.bestiarum and two as A.veronii. the plasmid-mediated quinolone resistance determinants, qnrA, qnrB, qnrC and qnrS genes, were investigated by M-PCR, and sequence analysis was performed for nine qnr-positive isolates. According to the sequence analysis of the genes, qnr genes were characterized in six A.sobria, in two A.bestiarum and in one A.hydrophila isolate (9/45; 20%). When the sequence was compared with GenBank database, this gene was found as qnrS2. All qnrS-positive Aeromonas spp. isolates were ciprofloxacin-susceptible, while five of them were resistant to nalidixic acid. This study is the first research about the plasmid-mediated quinolone resistance and the presence of qnrS2 genes among Aeromonas spp. isolated from fishes and water in Turkey. in conclusion, various resistance genes of aquatic bacteria may constitute a potential risk for the transmission of those genes to other bacteria as well as clinical isolates