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Assessment of antimutagenic action of Celtis glabrata Steven ex Planch. (Cannabaceae) extracts against base pair exchange and frame shift mutations on Salmonella typhimurium TA98 and TA100 strains by Ames test
(TAYLOR & FRANCIS LTD, 2016) Akın, Duygu; Durak, Yusuf; Uysal, Ahmet; Güneş, Erdoğan; Aladağ, Mustafa Onur
Context: Celtis glabrata is used in Turkey for the treatment of various health disorders. Objective: The acetone, chloroform, ethanol, and methanol extracts of C. glabrata leaf, fruit, and seed were investigated to evaluate their antimutagenic activities. Material and methods: The antimutagenicity of these extracts was determined by Ames test against mutagens (4-nitro-O-phenylenediamine, 2-aminofluorene (2-AF), and sodium azide (SA)). The extracts were used at concentrations between 5 and 0.005 mg/plate. Results: The ethanol extracts of leaves exhibited strong antimutagenicity (70%) against 2-AF with S9 at 5 mg/plate on TA98. But methanol (61%, 53%) and acetone (53%, 52%) also revealed strong inhibition rates at concentrations of >= 0.5 mg/plate. Among the extracts, the highest activity (96%) was obtained from acetone extract against SA without S9, followed by chloroform extract (91%) at a dose of 5 mg/plate on TA100 with S9. Ethanol (without S9) and chloroform (with S9) extracts showed strong antimutagenicity at all doses. Exception of chloroform and acetone (without S9), all fruit extracts (with/without S9) manifested strong antimutagenicity at doses of >= 0.5 mg/plate on TA98 strain. Ethanol extracts revealed 68% inhibition against 2-AF on TA98. Acetone and ethanol extracts manifested 84% and 82% inhibition against SA on TA100, respectively. All the extracts of seeds revealed strong inhibition against 2-AF at >= 0.5 mg/plate doses on TA98, but acetone extract showed excellent antimutagenicity (94%). Moreover, the chloroform (74, 73, 63, 54%), acetone (74, 72, 70, 65%) and methanol (74, 67, 63, 61%) extracts of seeds revealed strong antimutagenic activity on TA100 against SA with S9. Discussion and conclusion: This plant may be natural source of antimutagenic agents.
Bazı Ticari ve Ev Yapımı Yoğurtlardan İzole Edilen Laktik Asit Bakterilerinin Antibiyotik Duyarlılıkları
(Selçuk Üniversitesi Fen Fakültesi Fen Dergisi, 2016) Çelik, Handan; Durak, Yusuf; Uysal, Ahmet
Bu çalışmada, ticari ve ev yapımı yoğurt örneklerinden izole edilen laktik asit bakterilerinin çeşitli antibiyotiklere karşı duyarlılıklarının araştırılması amaçlandı. İlk olarak suşların izolasyonu ve identifikasyonu yapıldı. Yoğurt kültürü bakterilerinden Streptococcus salivarius subsp. thermophilus’un izolasyonunda M17 agar (Merck) kullanıldı. İnoküle edilen plaklar 37°C’de 48-72 saat inkübe edildi. Lactobacillus delbrueckii subsp. bulgaricus’un izolasyonunda ise de Man Rogosa Sharp Agar (MRS agar, Merck) kullanıldı. Plaklar 37°C’de 48-72 saat inkübe edildi. İzole edilen kolonilerin mikroskobik ve makroskobik incelemeleri yapıldı. Elde edilen 19 laktobasil ve 19 streptokok suşunun antibiyotik duyarlılık ve dirençliliklerinin belirlenmesi için Clinical and Laboratory Standards Institute tarafından önerilen disk difüzyon metodu uygulandı. Bu amaçla ticari olarak temin edilen 10 farklı antibiyotik diski kullanıldı. İnkübasyon süresi sonunda inhibisyon zon çapları ölçüldü. Streptokok suşlarının en fazla trimetoprim-sülfometaksazol (%84.21), sefotaksim (%31.57) ve gentamisin'e (%26.35) karşı dirençli olduğu belirlendi. Bu suşların tamamının kloramfenikol, vankomisin, ampisilin, eritromisin ve ofloksasin'e duyarlı oldukları gözlendi (%100). Laktobasil suşları trimetoprimsülfometaksazol ve ofloksasin'e karşı %100, gentamisine karşı ise %52.6 oranında dirençli görüldü. Laktobasil suşlarının yedi antibiyotiğe karşı (kloramfenikol, vankomisin, rifampin, sefotaksim, ampisilin, tetrasiklin ve eritromisin) %100 oranında duyarlı oldukları belirlendi. Her iki suş grubu kıyaslandığında, vankomisin, eritromisin ve ampisilin'in bu suşlara karşı en etkili antimikrobik ajanlar oldukları gözlendi. Laktobasil suşlarının, gentamisin'e karşı direnç oranı, Streptokok suşlarına göre daha yüksek görüldü.
Boğaz Kültürleri?nden I?zole Edi?len Beta-hemoli?ti?k Streptokoklarin I?denti?fi?kasyonu, Ti?plendi?ri?lmesi? Ve Anti?bi?yoti?k Ve Eri?tromi?si?n Di?renç Profi?lleri?ni?n Beli?rlenmesi?
(Selçuk Üniversitesi Fen Fakültesi, 2014) Akın, Duygu; Uysal, Ahmet; Durak, Yusuf
A grubu beta hemolitik streptokoklar (AGBHS) sıklıkla üst solunum yolu enfeksiyonlarından izole edilen ajanlardan biridir. Streptokok enfeksiyonları dünyada, öncelikle streptokok farenjit olmak üzere, doktor muayenesi, ilaç tedavisi ve iş günü kayıplarını kapsayan çok fazla miktarda maddi kayıplara neden olmaktadır. Çalışmamızda AGBHS'ların API 20 Strep sistemi ile identifikasyonu, patojen türlerin sayı ve oranları ve kullanılan antibiyotiklere dirençlerinin belirlenmesi amaçlanmıştır. Konya şehir merkezindeki çeşitli hastanelerde, akut tonsillofarenjit ön tanısı konulan hastalardan boğaz kültürü örnekleri alındı. Örnekler peptonlu suda bir saat ön inkübasyona tabi tutuldu. Ardından % 5 koyun kanlı Mueller-Hinton Agar’a (MHA) ekildi. Suşların grupları lateks aglütinasyon testi (SLIDEX ® Strepto Plus, Biomerieux) ile belirlendi. 373 örnek içerisinde Basitrasin’e duyarlı, Trimetoprim-sulfometaksazol'e dirençli, katalaz negatif, gram pozitif toplam 96 suş beta-hemolitik streptokok (AGBHS) olarak tanımlandı. Ayrıca API 20 Strep sistemi ile 96 adet AGBHS suşu tür seviyesinde sınıflandırıldı. CLSI önerileri doğrultusunda disk difüzyon yöntemi ile AGBHS suşlarının kullanılan antibiyotiklere karşı direnç ve duyarlılıkları belirlendi. Suşların antibiyotik direnç profilleri, çoklu antibiyotik direnç indeksleri ve eritromisin direnci tespit edildi. Çalışmadan elde edilen verilere göre, örneklerin % 25.73'ü AGBHS olarak tanımlandı. 96 suşun 13 farklı tür içerisinde dağılım gösterdiği görüldü. En baskın türlerin sırasıyla; Streptococcus acidominimus (34 suş), Streptococcus pyogenes (23 suş), Streptococcus oralis (9 suş), Streptococcus mitis 1 (7 suş) ve Streptococcus agalactiae (7 suş) olduğu belirlendi. Suşlar en fazla direnci tetrasikline (14 suş, 14.5%), takiben ampisilin ve eritromisine (13 suş, % 13.5); klaritromisine (10 suş, % 10.4); klindamisine (4 suş, % 4.1) gösterdi. AGBHS'lar birbirinden farklı 16 direnç profili ortaya koydu. Çoklu antibiyotik direnç indeksine göre 8 suş 0.2 değerinden büyük bir indeks gösterdi. Sonuç olarak, ülkemizde AGBHS suşlarının patojen profilleri belirlendi ve eritromisin direncinin ülkemizde önceden yapılan çalışmaların verileri ile kıyaslandığında yüksek olduğu ortaya kondu. Bu oranın şimdilik sorun olmadığı fakat aralıklı olarak direnç seviyelerinin ülke genelinde izlenmesinin faydalı olacağı kanaatine varıldı
Centaurea pterocaula özütlerinin antioksidan ve antimutajenik özellikleri ile enzim inhibitör potansiyellerinin incelenmesi
(MARMARA UNIV, FAC PHARMACY, 2016) Uysal, Ahmet; Zengin, Gökhan; Durak, Yusuf; Aktümsek, Abdurrahman
Bu çalışmanın amacı, Centaurea pterocaula bitkisinden elde edilen üç özütün (etil asetat, metanol ve su) antioksidan kapasiteleri, mutajenik/antimutajenik özellikleri ve enzim inhibitör etkilerini değerlendirmektir. Özütlerin antioksidan özellikler radikal giderme (süpürme) (DPPH testi), indirgeme gücü (FRAP ve CUPRAC testleri), fosfomolibdat ve metal şelatlama testleri gibi in vitro antioksidan yöntemler kullanılarak araştırıldı. Özütlerin enzim inhibitör etkiler kolinesteraz, tirozinaz, amilaz ve glukozidaza karşı test edildi. Ames testi özütlerin mutajenik/antimutajenik özelliklerini göstermek için kullanıldı. Metanol özütünün en güçlü radikal giderme (31.06 mgTE/g özüt) ve indirgeme gücüne (CUPRAC testinde 66.95 mgTE/g özüt ve FRAP testinde 51.03 mgTE/g özüt) sahip olduğu tespit edildi. Ayrıca, etil asetat özütü glikozidaz enzimi hariç test edilen tüm enzimlere karşı en güçlü etkiyi sergiledi. Özütlerin toplam fenolik ve flavonoid içerik sırasıyla 15.77-25.22 mg GAE/g özüt ve 0.67-31.44 mg RE/g özüt aralıklarında değiştiği bulundu. Test edilen özütlerin hiçbirinde mutajenik etki görülmezken, bazı örneklerin önemli oranda antimutajeniteye sahip olduğu tespit edildi. Metabolik aktivasyon (S9) varlığında etil asetat ve metanol özütlerinin 2-aminofloren’e karşı 5000 µg/plak dozlarda çok güçlü (sırası ile % 92 ve % 92) antimutajenik etkiye sahip oldukları bulundu. Bu çalışmanın sonuçlarına göre, C. pterocaula yeni nutrasötik veya farmasötiklerin geliştirilmesinde potansiyel bir kaynak olarak düşünülebilir.
CHARACTERIZATION OF ESCHERICHIA COLI STRAINS ISOLATED FROM WELL WATERS: MOLECULAR TYPING BY PULSED-FIELD GEL ELECTROPHORESIS, ANTIBIOTIC RESISTANCE PATTERNS AND PLASMID PROFILES
(PARLAR SCIENTIFIC PUBLICATIONS (P S P), 2013) Uysal, Ahmet; Durak, Yusuf; Arslan, Ugur
A number of previous studies have shown that characterization and determination of genetic relationships of the microorganisms in case of possible outbreak are of vital importance. In this study, the genetic relations and genetic diversities, susceptibility to antibiotics and plasmid profiles of 43 Escherichia coli isolates recovered from well water samples were investigated.. The pulsed-field gel electrophoresis (PFGE) method was used to identify the genetic relations and diversities of E. coli isolates. PFGE revealed 30 pulsotypes represented by 6 subtypes among the strains according to evaluation of restriction profiles. Antibiotic susceptibility tests were conducted against 15 antibiotics by using a disc diffusion method. The isolates exhibited four different types of resistance profiles. The strains showed the greatest resistance to ampicillin (97.67%), followed by ticarcillin-clavulanic acid (9.3%) and cefuroxime and ceftazidime (6.97%). Plasmid isolation studies of the strains conducted by the method of alkaline lysis revealed that 19 (44.18%) of 40 E. coli strains contain 19 different plasmid bands ranging between 78.2 and 2.6 kb. Based on the results obtained from tests, PFGE analysis revealed very high genetic diversity among the strains. Antibiotic resistance ratios increased in E. coli isolates when compared with data obtained from previous studies. Plasmids of E. coli strains demonstrated random distribution, and any significant correlation between antibiotic resistance patterns and plasmids has not been found. E. coli strains leaked to the well water sources were not closely related. Studies and surveillances should be conducted periodically to see resistance of environmental strains.
Characterization of Klebsiella pneumoniae Strains Isolated from Urinary Tract infections: Detection of ESBL Characteristics, Antibiotic Susceptibility and RAPD Genotyping
(POLSKIE TOWARZYSTWO MIKROBIOLOGOW-POLISH SOCIETY OF MICROBIOLOGISTS, 2013) Aladağ, Mustafa Onur; Uysal, Ahmet; Dündar, Niyazi; Durak, Yusuf; Güneş, Erdoğan
In this study, a hundred Klebsiella pneumoniae strains isolated from urinary tract infections were evaluated in terms of genotyping, susceptibility to certain antibiotics and detection of extended spectrum of beta lactamase (ESBL) production. The random amplified polymorphic DNA (RAPD-PCR) method was used to identify the genetic differentiation of K. pneumoniae isolates. A total of 26 different DNA bands ranging between 334 bp and 28033 bp were detected among the strains. It was found that 100 K pneumoniae strains revealed 11 different RAPD profiles. Antibiotic susceptibility tests were conducted using a disc diffusion method against 16 antibiotics. Fifty-five different resistance profiles were determined among the strains. ESBL-productions of the strains were determined by the double disc synergy test (DDST) and ESBL E-test methods. ESBL production rates among the strains were found to be 55% by E-test method and 45% by DDST method. While ESBL-producing K pneumoniae strains showed the greatest resistance to penicillin G (100%), followed by piperacillin (92.7%) and erythromycin (85.4%),the resistance rates of non ESBL producing strains to those antibiotics were determined as 97.8%, 88.8% and 88.8%, respectively. Both groups of strains showed the highest sensitivity to meropenem. Based on the results obtained from the study, it was concluded that the detection of ESBL-producing strains by the E-test method was more sensitive than by the DDST method. Phenotypic and genotypic identification methods should be used together to detect ESBL presence. The RAPD-PCR method alone will not be adequate in the genotyping of the strains and alternative DNA-based methods should be used.
CHARACTERIZATION OF UROPATHOGENIC ESCHERICHIA COLI STRAINS: ANTIBIOTIC RESISTANCE PATTERNS, DETECTION OF ESBL GENES AND INTERACTIONS BY LYTIC PHAGES
(PARLAR SCIENTIFIC PUBLICATIONS (P S P), 2018) Uysal, Ahmet; Gunes, Erdogan; Arslan, Emine; Durak, Yusuf
In this study, 97 Escherichia coli strains isolated from urinary tract infections were evaluated in terms of phenotypic diversity, susceptibility to sixteen antibiotics, and extended spectrum of beta lactamase (ESBL) characteristics. The bacteriophage interactions was used to identify the relations of the E.coli isolates. Results showed that 21 of the 76 typable strains revealed 19 different phage types. Phage types of 21 strains could not be determined. Antibiotic susceptibility tests, performed against sixteen antibiotics, showed that although the isolates revealed 44 different types of resistance profiles, the strains showed the greatest resistance to cephalothin (54.6%), followed by tetracycline (53.6%), nalidixic acid (44.3%), and aztreonam and ofloxacin (29.8%). There was no resistance to amikacin and meropenem, and all strains were susceptible to meropenem. ESBL detection conducted by double disc synergy and multiplex polymerase chain reaction methods showed that 13 of 97 (13.4%) strains were ESBL-producing. Of the 13 ESBL-producing isolates, two carried bla(CTX-M), six bla(TEM), five bla(OXA), and one bla(TEM) and bla(SHV) at same time. We concluded that lytic phages could not be successful for typing the strains phenotypically. The monitoring of antimicrobial resistance levels and antimicrobial usage in humans should be an integral part of the prevention and control of antimicrobial resistance.
Evaluation of Antioxidant and Antimicrobial Activity of Vitex Agnus Castus L.
(Parlar Scientific Publications (P S P), 2010) Maltaş, Esra; Uysal, Ahmet; Yıldız, Salih; Durak, Yusuf
Antioxidant and antimicrobial activities of methanolic extract of Vitex agnus castus were studied. The antioxidant properties of the extracts were evaluated using different antioxidant tests, including ferric chelating, scavenging activity of hydrogen peroxide and cupric reducing antioxidant capacity. The highest antioxidant activity was observed to be 93.5 +/- 0.8% by scavenging activity of hydrogen peroxide. However, total flavonoid and phenolic content of the methanolic extract were determined. Antimicrobial activity tests were carried out using disc diffusion method and broth microdilution method with 7 bacteria and 1 yeast. Results suggested that Vitex agnus castus may be important in variety improvement, nutraceuticals, bio-pharmaceuticals and food additives as possible cost-effective natural antioxidant.
Genetic Diversity of Escherichia Coli Strains Isolated From Various Foods
(ELSEVIER SCIENCE BV, 2012) Uysal, Ahmet; Durak, Yusuf; Güneş, Erdoğan; Aladağ, Mustafa Onur
[Abstract not Available]
Hamam Böceklerinin (Blattodea:Blattidae) Patojen Bakteriler Yönünden Araştırılması
(Selçuk Üniversitesi, 2002) Durak, Yusuf; Ertürk, Cihan; Özkalp, Birol; Duman, Rüstem
Bu çalışmada, ev ve hastahane ortamlarından yakalanan hamam böceklerinin, patojen ve potansiyel patojen bakteriler yönünden mekanik vektör rolü araştırılmıştır.Ev ortamlarından 59 ve hastahane ortamlarından 54 olmak üzere, 113 adet hamam böceği toplanmıştır. Toplanan 113 örneğin 40'ı (% 35.4) Blatella germanice, 38'i (%33.6) Blatta orientalis ve 35’i (%31.0) Períplaneta americana türü olarak teşhis edilmiştir. Ev ortamlarından toplanan 59 örneğin 35’inden (%59) Escherichia coli bakteri türü izole edilirken, 24'ü (%41) steril bulunmuştur. Hastahane ortamlarından toplanan 54 örneğin 34'ünden (%63) E. coli, 8'inden (%15) E.coli+Proteus vulgaris, 5'inden (%9) P.vulgaris, 2’sinden (%4) Klebsiella pneumoniae bakteri türleri izole edilirken, 5‘i (%9) steril bulunmuştur.Bulgular, hamam böceklerinin bazı patojen bakterilerin neden olduğu enfeksiyonların yayılmasında rol oynayabileceklerini göstermiştir.
Hamam Böceklerinin (Blattodea:Blattidae) Patojen Bakteriler Yönünden Araştırılması
(Selçuk Üniversitesi Fen-Edebiyat Fakültesi, 2002) Durak, Yusuf; Duman, Rüstem; Özkalp, Birol; Ertürk, Cihan
Bu çalışmada, ev ve hastahane ortamlarından yakalanan hamam böceklerinin, patojen ve potansiyel patojen bakteriler yönünden mekanik vektör rolü araştırılmıştır.Ev ortamlarından 59 ve hastahane ortamlarından 54 olmak üzere, 113 adet hamam böceği toplanmıştır. Toplanan 113 örneğin 40'ı (% 35.4) Blatella germanice, 38'i (%33.6) Blatta orientalis ve 35’i (%31.0) Períplaneta americana türü olarak teşhis edilmiştir. Ev ortamlarından toplanan 59 örneğin 35’inden (%59) Escherichia coli bakteri türü izole edilirken, 24'ü (%41) steril bulunmuştur. Hastahane ortamlarından toplanan 54 örneğin 34'ünden (%63) E. coli, 8'inden (%15) E.coli+Proteus vulgaris, 5'inden (%9) P.vulgaris, 2’sinden (%4) Klebsiella pneumoniae bakteri türleri izole edilirken, 5‘i (%9) steril bulunmuştur.Bulgular, hamam böceklerinin bazı patojen bakterilerin neden olduğu enfeksiyonların yayılmasında rol oynayabileceklerini göstermiştir.
Hyoscyamus Reticulatus’un Hekzan Ve Su Özütleri?ni?n Anti?oksi?dan Ve Anti?mi?krobi?yal Özelli?kleri? Üzeri?ne Bi?r Çalışma
(Selçuk Üniversitesi Fen Fakültesi, 2014) Güneş, Erdoğan; Zengin, Gökhan; Uysal, Ahmet; Aktümsek, Abdurrahman; Durak, Yusuf
Bu çalışmanın amacı Hyoscyamus reticulatus’dan elde edilen hekzan ve su özütlerinin antioksidan kapasitelerini ve antimikrobiyal etkilerini belirlemektir. Antioksidan kapasite radikal süpürme (DPPH testi), toplam antioksidan kapasite, demir ve bakır indirgeme testlerini içeren dört farklı test sistemi ile araştırıldı. Antimikrobiyal etki sıvı mikro dilüsyon metodu ile değerlendirildi. Fosfomolibdat testi (total antioksidan kapasite) dışında, su özütünün hekzan özütünden daha yüksek antioksidan aktiviteye sahip olduğu belirlenmiştir. Toplam fenolik miktarı hekzan ve su özütünde sırasıyla 15.86 mg GAE/g ve 24.25 mg GAE/g olarak bulunmuştur. Ek olarak, hekzan özütü su özütüne kıyasla önemli bir antimikrobiyal etki göstermiştir. Bu çalışma ile elde edilen sonuçlar açıkça Hyoscyamus reticulatus’un oksidatif ve enfeksiyöz süreçlerde, doğal ajanların bir kaynağı olarak önemli bir potansiyele sahip olduğunu göstermiştir.
Investigation mutagenic and antimutagenic potentials of root methanol extract of Ferula elaeochytris Korovin by salmonella/microsome test system
(ELSEVIER SCIENCE BV, 2016) Durak, Yusuf; Uysal, Ahmet; Gunes, Erdogan
[Abstract not Available]
Investigation of Methicillin Resistance of Staphylococcus aureus Strains Isolated from Various Sources by Different Methods
(DR M N KHAN, 2013) Gunes, Erdogan; Durak, Yusuf
Object of this study is to determine methicillin resistance of 150 strains of Staphylococcus aureus isolated and identified from various sources by the methods of oxacillin agar screen, broth microdilution and oxacillin disc diffusion, to compare sensitivity and specificity of these methods by making oxacillin agar screen test reference and to determine multi-antibiotic resistance in these strains. 16 (10.7%) of the 150 strains were determined as Methicillin-Resistant S.aureus (MRSA) through the methods of agar screen and microdilution while 17 (11.3%) strains were found as the same through the method of disc diffusion. Agar screen and microdilution methods were found as 100% compatible with each other. Sensitivity of the disc diffusion method was calculated as 100% while its specificity was calculated as 99.2%. Antibiotic susceptibility tests conducted by using the disc diffusion method against 10 antibiotics showed that the highest resistances of MRSA and MSSA (Methicillin-Susceptible S. aureus) strains were determined as 100% and 93.3% to penicillin, 81.2% and 5.2% to tetracycline, 62.5% and 1.5% to ofloxacin, 56.2% and 0.7% to rifampin respectively while all strains were found susceptible to linezolid and vancomycin. It was seen that multiple-antibiotic resistance in MRSA strains are higher compared with that in MSSA strains. It has been thought that linezolid may be an alternative for vancomycin in curing MRSA infections.
Investigation of Mutagenic Effects of Some Plant Growth Regulators on Salmonella/ Microsome Test System
(Parlar Scientific Publications (P S P), 2010) Uysal, Ahmet; Durak, Yusuf; Aladağ, Mustafa Onur
In this study, beta-naphthoxyacetic acid (BNOA), 4-chlorophenoxyacetic acid (4-CPA) and 2,4-dichlorophenoxyacetic acid (2,4-D) used as plant growth regulators were investigated in order to determine their possible mutagenic activity by Salmonella/microsome test system. Non-toxic doses of BNOA (500, 100, 50, 10, 1 mu g/plaque), 4-CPA (200, 100, 50, 25, 10 mu g/plaque) and 2,4-D (100, 50, 10, 1, 0.1 mu g/plaque) were used in the assays. Assays were carried out through the Salmonella typhimurium TA 98 and TA 100 strains under the conditions both with and without metabolic activation (S9). Numbers of revertants determined in the assays performed with nontoxic doses were compared to those of control plates. Any significant increases in the number of revertants were not observed, in the presence or absence of metabolic activation (S9). Based on the results, it was concluded that BNOA, 4-CPA and 2,4-D were not found to be mutagenic or promutagenic in the Salmonella/microsome test system.
Investigation of mutagenic effects of some plant growth regulators on Salmonella/microsome test system
(2010) Uysal, Ahmet; Durak, Yusuf; Aladağ, Mustafa Onur
In this study, beta-naphthoxyacetic acid (BNOA), 4-chlorophenoxyacetic acid (4-CPA) and 2,4-dichlorophenoxyacetic acid (2,4-D) used as plant growth regulators were investigated in order to determine their possible mutagenic activity by Salmonella/microsome test system. Non-toxic doses of BNOA (500, 100, 50, 10, 1 ?g/plaque), 4-CPA (200, 100, 50, 25, 10 ?g/plaque) and 2,4-D (100, 50, 10, 1, 0.1 ?g/plaque) were used in the assays. Assays were carried out through the Salmonella typhimurium TA 98 and TA 100 strains under the conditions both with and without metabolic activation (S9). Numbers of revertants determined in the assays performed with nontoxic doses were compared to those of control plates. Any significant increases in the number of revertants were not observed, in the presence or absence of metabolic activation (S9). Based on the results, it was concluded that BNOA, 4-CPA and 2,4-D were not found to be mutagenic or promutagenic in the Salmonella/microsome test system. © by PSP.
Konya Yöresindeki Koyunlarda Atıklara Neden Olan Chlamydia Psittaci İnfeksiyonlarının Komplement Fikzasyon Testi ile Araştırılması
(SCIENTIFIC TECHNICAL RESEARCH COUNCIL TURKEY, 1998) Duman, Rüstem; Durak, Yusuf
In this study, a total of 224 blood sera which were collected from aborted ewes during 1993-1994 lambing season in Konya district and analysed for the presence of antibodies to Chlamydia psittaci using complement fixation test (CFT). In CFT, a suspension which have been prepared from the yolk sacs of embryonated hens' eggs infected with S26/3 strain of Chiamydia psittaci which was provided from Pendik Veterinary Control and Research Institute as antigen, guinea pig serum as a source of complement and rabbit antisera immunized with sheep erythrocyte which was prepared at the Department of Microbiology Veterinary Faculty, Selcuk University as haemolytic serum were used. Fourty five samples (20%) out of 224 were positive for Chiamydia psittaci antibodies with a titration range of 1/16-1/32, 28 samples (12.5%) were decided to be suspected with a titer of 1/8 and the remaining 151 samples (67.4%) were negative with titres of less than 1/8.
New Prospective Materials for Chemoprevention: Three Phlomis
(SCIENCEDOMAIN INT, 2016) Uysal, Ahmet; Gunes, Erdogan; Sarikurkcu, Cengiz; Celik, Handan; Durak, Yusuf; Uren, Mehmet Cemil
Aim: Plants are permanent sources of biologically active compounds, used by about 80% of the world population as manufactured drugs. The aims of this paper are to determine the mutagenic and antimutagenic activities of methanol, ethyl acetate and water extracts from Phlomis nissoli (PNM, PNE, PNW) Phlomis pungens var. pungens (PPM, PPE, PPW) and Phlomis armeniaca (PAM, PAE, PAW) against well-known mutagens. Methodology: Mutagenic/antimutagenic activities were determined by Ames test. Results: Extracts of P. nissoli, P. pungens and P. armeniaca were not mutagenic against TA98 and TA100 in the condition both with and without S9 mix. The strongest antimutagenic action was revealed by PNE extract at a dose of 5000 mu g/plate against 2-amino-flourene with 96% inhibition for TA98 with S9 mix. PNM extract alleviated the mutagenic action of 2-amino-anthracene and exhibited strong inhibition rates (93%, 78%, 57%, respectively) with S9 mix at all doses for TA100 strain. While PAE extract manifested 95%, 91% and 84% inhibition against 2-amino-flourene for TA98, it revealed 90%, 84%, and 87% inhibition ratios, respectively, making them as strongly antimutagenic against 2-amino-anthracene for TA100 with S9 mix. Conclusion: P. nissoli, P. pungens and P. armeniaca extracts have significant antimutagenic capacities and they can represent a good model for the development of new drug formulations in pharmaceutical industry and they could be used in food industry as chemoprevention agent.
Porphyromonas gingivalis Lipopolysaccharide Induces a Pro-inflammatory Human Gingival Fibroblast Phenotype
(SPRINGER/PLENUM PUBLISHERS, 2017) Bozkurt, S. Buket; Hakki, Sema S.; Hakki, Erdogan E.; Durak, Yusuf; Kantarci, Alpdogan
Human gingival fibroblasts (HGFs) are the major constituents of the gingival tissues responsible for the synthesis and degradation of the connective tissue while actively participating in immune reactions and inflammation. The aim of this study was to test the impact of lipopolysaccharide (LPS) from Porphyromonas gingivalis (P. gingivalis) on human gingival fibroblasts. Human gingival fibroblasts were treated with different P. gingivalis LPS concentrations. Cell survival rate was evaluated with 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) after 24 h. Cell proliferation was determined by counting cells on days 3 and 12. Expression of matrix metalloproteinases (MMPs), tissue inhibitors of MMPs (TIMPs), and pro-inflammatory cytokine transcripts in HGFs was determined by quantitative PCR (Q-PCR) analysis on days 3 and 8. P. gingivalis LPS decreased cell proliferation on day 3 (p < 0.05) compared to the control group without significantly impacting the cell survival (p > 0.05).The experiments showed that P. gingivalis LPS dose-dependently and differentially modulated the expression of MMP-1, 2, and 3 and TIMP-1 and 2 on days 3 and 8. TIMP-1 expression was significantly induced in P. gingivalis LPS-treated cells while TIMP-2 was increased in response to 10 and 30 ng/ml of LPS on day 3. P. gingivalis LPS induced up-regulation of MMP-1/TIMP-1 ratio on day 3 and increased MMP-2/TIMP-2 ratio on day 8 dose-dependently. Expression of interleukin (IL)-6 and IL-8 was stimulated at higher concentrations (1000 and 3000 ng/ml) of LPS. These findings demonstrate that P. gingivalis LPS suppresses cell proliferation and leads to increased pro-inflammatory changes in HGFs, suggesting that P. gingivalis LPS-induced modification of phenotypic and inflammatory characteristics in HGF could potentially be a pathogenic mechanism underlying the tissue destruction.
Pulsed-field gel electrophoresis typing, antibiotic resistance, and plasmid profiles of Escherichia coli strains isolated from foods
(CANADIAN SCIENCE PUBLISHING, NRC RESEARCH PRESS, 2012) Uysal, Ahmet; Durak, Yusuf
Bacterial contamination in foods and antimicrobial resistance levels of common pathogenic strains causing food-borne disease are important in human health. Thus, typing technologies are important tools to determine primary sources of bacterial contamination. In this study, 40 Escherichia coli strains isolated from 85 food samples were evaluated in terms of genetic diversity, susceptibility to certain antibiotics, and plasmid profiles. Pulsed-field gel electrophoresis was used to identify the genetic relations of E. coli isolates. It was determined that the 40 E. coli strains revealed 32 different pulsotypes represented by 6 subtypes. Antibiotic susceptibility tests conducted by using a disc diffusion method against 15 antibiotics showed that although the isolates revealed 14 different types of resistance profiles, the strains showed the greatest resistance to ampicillin (77.5%), followed by ticarcillin-clavulanic acid (30%), tetracycline (22.5%), and cephalothin (14.5%). Plasmid isolations studies of the strains conducted by the method of alkaline lysis revealed that 18 (45%) of 40 E. coli strains contain 31 different plasmid bands ranging between 64.4 and 1 kb. The results showed that PFGE was a powerful method in tracking sources of food contamination and that the antibiotic resistance levels of food isolates were high and should be monitored.

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