Effect of various polymerization protocols on the cytotoxicity of conventional and self-adhesive resin-based luting cements.

OBJECTIVES: This study evaluated the cytotoxicity of resin-based luting cements on fibroblast cells using different polymerization protocols. MATERIALS AND METHODS: Two conventional dual-polymerized (RelyX ARC, VariolinkN) and two self-adhesive resin cements (RelyX Unicem, Multilink Speed) specimens were polymerized using four different polymerization protocols: (a) photo-polymerization with direct light application, (b) photo-polymerization over ceramic and (c) resin nano-ceramic discs and (d) auto-polymerization. The specimens were then assigned to four groups to test cytotoxicity at 0, 1, 2 and 7 preincubation days (n = 5). MTT test was performed using NIH/3T3 fibroblast cells. Data were analysed using three- and one-way ANOVA. Multiple comparisons were made using Bonferroni post hoc test (p < 0.05). RESULTS: The highest cytotoxic values were recorded at day 2 for conventional resin cements and at day 0 for self-adhesive resin cements. Self-adhesive resin cements showed the most cytotoxic effect at the second day, while conventional resin cements presented immediate cytotoxicity. Auto-polymerized resin specimens and especially Multilink Speed demonstrated the most cytotoxic effect regardless of the preincubation time. Cytotoxicity of cements tested reached the lowest level at day 7. Interposition of ceramic or nano-ceramic restorative material did not significantly affect the cytotoxicity of tested luting cements (p > 0.05). CONCLUSIONS: Cytotoxicity of dual-polymerized resin cements was material-dependent and decreased gradually up to 7 days. Photo-polymerization plays an important role in reducing the cytotoxic effects. CLINICAL RELEVANCE: When luting ceramic or resin nano-ceramic restorations of which thickness does not exceed 2 mm, the level of cytotoxicity with the tested materials is not significant. Luting of restorative materials that do not allow for light transmission such as metal-fused porcelain, clinicians should be cautious in the use of dual-polymerized conventional resin cements as only auto-polymerization of resin cements takes place under such materials.

Do Nano-crystalline Silver-Coated Hernia Grafts Reduce Infection?

PURPOSE: Inguinal hernia repairs are the most common interventions in adults in general surgery clinics. Depending on the type of mesh and repair, the incidence of mesh-related infection ranges from 0.6 to 8%. Methicillin-resistant Staphylococcus aureus is the most common microorganism causing graft infection. The aim of this study was to investigate the efficacy of nano-crystalline silver-coated polypropylene grafts against graft infection created with MRSA in rats. METHODS: A total of 60 female, Wistar albino rats were used in the study. Polypropylene grafts 1 × 1 cm in size were coated in silver ion-doped, calcium phosphate-based, antibacterial ceramic powder (NS-coated graft) to provide an antimicrobial effect. The MRSA seeding procedure was applied at the same time as surgery. In Group 1, normal graft was applied without MRSA seeding, in Group 2, normal graft with MRSA seeding, in Group 3, NS-coated graft without MRSA seeding, and in Group 4, NS-coated graft with MRSA seeding. For the groups which were to be infected, the bacteria were seeded in the surgical area during the operation. On the 7th day postoperatively, all the animals were killed. The grafts were removed and one from each group was examined under electron microscope and the others were implanted in culture medium and the number of colonies was counted after 24 h. RESULTS: In Groups 1 and 3, the incision site was seen to have healed on day 3, no clinical surgical area infection was seen during follow-up, and in the exploration made on the 7th day, no findings of infection were observed. In Group 2, hyperemia and collection were seen to have formed on day 3, abscess had started to form in all the rats of this group on day 4, a purulent discharge in the wound site had started in 12 animals on day 5, separation of the wound site was observed in 6 on day 6, and in the exploration on day 7, there was seen to be a fibrin and pus-rich collection around the graft in all cases. In Group 4, there were hyperemia and collection in 6 animals on day 4, and in 3 of these, abscess was seen to have formed on the 5th day. No purulent discharge or wound separation was observed. In the exploration on the 7th day, it was seen that in the animals with abscess development, the formation was of a localized abscess. The results of the cultures of the grafts removed from Groups 1 and 3 showed no production, whereas production was seen in all the grafts removed from Groups 2 and 4. Clinical surgical area infection was seen to have developed in 100% of Group 2 and in 40% of Group 4. In the comparison of the number of colonies, a statistically significantly lower number of bacteria were determined in Group 4 compared to Group 2 (p < 0.05). In the SEM images taken of Group 2, bacteria clusters were seen attached to the graft. CONCLUSION: Consistent with previous findings in the literature, the NS-coated polypropylene graft was seen to have a significantly better bactericidal effect than the normal polypropylene graft. Development of NS-coated grafts seems to be a reliable and applicable method to reduce the incidence of postoperative graft infection.

Determination of the Minimum Inhibitory Concentrations of Alexidine and Chlorhexidine Against Enterococcus faecalis and Candida albicans: An In Vitro Study.

INTRODUCTION: The root canal system must be mechanically instrumented and chemically cleaned using various antimicrobial irrigants in a sequential manner or in combination for the elimination of necrotic pulp tissue and reducing the number of root canal bacteria. For this reason, new methods and materials are continuously being developed to achieve the objectives of endodontic treatment. MATERIALS AND METHODS: E. faecalis (ATCC 29212) and C. albicans (ATCC 90028) standard strains were used for this study. Colonies of E. faecalis and C. albicans were harvested from the agar plates and suspended in 4 mL of phosphate buffered saline (PBS). Microorganisms were diluted to obtain a suspension of approximately 108 colony-forming units/mL (CFU/mL) in sterile PBS using McFarland standard tubes no. 0.5. RESULTS: After a two-minute contact time, all alexidine (ALX) concentrations used in this study eradicated all E. faecalis strains, while chlorhexidine (CHX) didn't kill 100% of E. faecalis at 0.25% and lower concentrations even after a five-minute contact time. ALX also eradicated C. albicans at all concentrations even after a one-minute contact time. CHX showed antifungal activity against C. albicans at all concentrations higher than 0.031% after a one-minute contact time. CONCLUSION: A 0.0156% concentration of ALX can be a good alternative to CHX as an irrigation solution in endodontic treatment when used for one minute against E. faecalis and C. albicans.

[A new method for the disruption of cell walls of gram-positive bacteria and mycobacteria on the point of nucleic acid extraction: sand method]. / Nükleik asit ekstraksiyonunda kullanilmak üzere, gram-pozitif bakteriler ve mikobakterilerin hücre duvarlarinin ortadan kaldirilmasinda yeni bir yöntem: Kum yöntemi.

Nowadays molecular methods are widely used in the rapid diagnosis of infectious agents. Polymerase chain reaction (PCR) is the most preferred method for this purpose. Obtaining sufficient and pure DNA or RNA is important for the PCR. Different DNA extraction protocols such as phenol-chloroform, proteinase K, glass beads and boiling have been used successfully for DNA isolation from gram-negative bacteria. However since gram-positive bacteria have a thicker layer of peptidoglycan and mycobacteria have complex glycolipids in their cell walls, for the isolation of DNA or RNA from these microorganisms, the complex cell wall structure must be eliminated. For this purpose, the bacterial cell wall must be completely or partially removed forming sferoblast using lysostaphin in the Staphylococcus genus as gram-positive bacteria and using a chemical like cetyltrimethyl ammonium bromide for the Mycobacterium genus. In this study, we planned to use sand particles for the mechanical elimination of the cell wall without any need for chemicals and we called this procedure as "sand method". For the purpose of DNA extraction, the fine-grained sand was washed with ddH(2)O without losing small particles and then sterilized by autoclaving. For the purpose of RNA extraction; the sand was washed with ddH(2)O, incubated for 30 minutes with 10% HCl, and then autoclaved. A methicillin-resistant Staphylococcus aureus (MRSA) strain previously isolated and identified from a clinical specimen was mixed in 100 µl Tris-EDTA buffer with 100 mg sand. The mixture of bacteria and sand was vortexed at the maximum speed for 5 minutes. The MRSA-sand mix was treated with proteinase K and phenol-chloroform, and ethanol precipitation protocol was then followed for obtaining DNA. For comparison of the sand method with the other methods, the same amount of bacteria used in the sand method was incubated for one hour with lysostaphin, and then the proteinase K DNA extraction method were completed in the same way used in the sand method. For obtaining RNA from M.tuberculosis H37Rv ATCC 25618, M.tuberculosis H37Ra ATCC 25177 and M.tuberculosis H37Rv Pasteur Institute RSKK 598 standard strains, bacteria were dissolved in 20 µl Tris-EDTA buffer with 100 mg sand. The mixture of bacteria and sand was vortexed at the maximum speed for 5 minutes. After that, the classic RNA extraction protocol using guanidinium thiocyanate-phenol-chloroform (GTPC) was completed. To investigate the usefulness of the obtained DNA, a PCR was performed with specific primers for staphylokinase and enterotoxin genes that were shown in the genome of the chosen MRSA strains from our previous studies. To investigate the usefulness of the obtained RNA from the sand method; first cDNA synthesis is completed. The PCR efficiency was then tested using primers specific to the efflux pump genes of M.tuberculosis including Rv1410c, Rv2333c, and DrrA genes. To compare the effect of the sand method, GTPC protocol was applied in the same amount of mycobacteria without the sand treatment. The DNA obtained from MRSA with the application of lysostaphin and the DNA obtained from MRSA by the sand method were run in agarose gel electrophoresis. The amount and purity of DNAs were measured with a spectrophotometer. The same amount and purity of the DNAs were approximately the same in both of the extraction methods. The existence of non-inhibitors of DNA in the sand method was shown with the PCR, which have worked efficiently with the DNAs obtained from the sand method. RNA was obtained efficiently from the Mycobacterium strains by the sand method, but no RNA could be obtained from the mycobacteria with the other methods. It was shown that the RNA obtained using the sand method worked effectively in both cDNA synthesis and PCR in which synthesized cDNA was used. The sand method described in the study worked effectively to obtain sufficient amount of pure DNA and RNA from the bacteria containing rigid cell walls that are difficult to obtain the nucleotide. It was concluded that, using the sand method instead of relatively expensive lysostaphin or other chemicals, has important advantages such as decreasing the cost and the shortening of the DNA extraction period.

[Investigation of seven different RNA viruses associated with gastroenteritis in children under five years old]. / Bes yas alti çocuklarda gastroenterite neden olan yedi farkli RNA virusunun arastirilmasi

Viruses are the most frequently detected etiologic agents of gastroenteritis seen in small children. In addition to classical gastroenteritis viruses namely rotavirus, norovirus, adenovirus type 40/41, astrovirus and sapovirus, some novel picornaviruses (Aichi virus, parechovirus, enterovirus) that have been identified in parallel to the developments in molecular diagnostic methods, thought to be associated with diarrhea in humans. However, the data are not enough to prove their actual roles in the pathogenesis of gastroenteritis. The aim of this study was to investigate the presence of rotavirus, norovirus, sapovirus, astrovirus, Aichi virus, parechovirus and enterovirus in the stool samples of children with diarrhoea by reverse-transcriptase polymerase chain reaction (RT-PCR). A total of 50 samples from children admitted to our hospital with diarrhoea between June-December 2012 were included in the study. All the patients were under 5 years of age. Routine bacteriological and parasitological examinations of the patients' stool samples were negative. Total RNAs were extracted from each of the samples and cDNAs were obtained by reverse transcription. All cDNAs were investigated first with the internal control (IC) using PCR. Thirty-one of the 50 cDNAs (62%) were found IC positive. Those 31 samples were further investigated in terms of rotavirus group A and C, norovirus (NoV) genogroup GI and GII, sapovirus, astrovirus, Aichi virus, parechovirus and enterovirus by PCR using specific primer pairs. The predicted sized PCR products obtained were cloned into the pBSK cloning vector and were sequenced. Sequences obtained were subjected to a BLAST search with registered sequences in the GenBank database for the confirmation of the PCR product. Out of 31 RNA positive stool specimens, 12 (38.7%) were found positive for five types of the target viruses. NoV GII (6/31, 19.3%) were detected as the most prevalent virus, followed by NoV GI (2/31, 6.5%), rotavirus group A (2/31, 6.5%), astrovirus (1/31, 3.2%) and sapovirus (1/31, 3.2%). The results of this study revealed that the most frequently detected agents were noroviruses (8/50, 16%) followed by rotavirus (2/50, 4%), astrovirus (1/50, 2%) and sapovirus (1/50, 2%). It was concluded that RT-PCR performed with the primers used in this study could be applied effectively for the molecular epidemiological analysis of RNA viruses leading to gastroenteritis. Larger scale studies conducted in different areas for longer time periods and with a larger population size will provide data for the epidemiological properties of agents of viral gastroenteritis.

[Comparison of in vitro antimicrobial activities of bioaggregate and mineral trioxide aggregate]. / Biyoagregat ve mineral trioksit agregatin antimikrobiyal etkilerinin in vitro olarak karsilastirilmasi

Treatment outcome of endodontic perforations depends on successful elimination of the associated microorganisms and infected tissues as well as the effective seal of the root-end or perforation site to prevent future contamination. Ideally, perforation repair material has to be bacteriostatic or bactericidal in order to prevent bacterial contamination as well as good sealing properties and biocompatibility. The aim of this study was to evaluate the antimicrobial effects of BioAggregate (BA) and Mineral Trioxide Aggregate (MTA) on the standard strains of Candida albicans, Enterococcus faecalis, Escherichia coli, Streptococcus mutans, Streptococcus sanguinis and Pseudomonas aeruginosa using the agar disc diffusion test. Colonies of each strains were harvested from the medium and microorganisms were diluted to obtain a suspension of approximately 108 cfu/ml. Petri plates with blood agar base with 5% sheep blood or Sabouraud dextrose agar (for C.albicans) were inoculated with experimental suspensions and BA and MTA discs prepared as 2 mm length and 6 mm diameter were placed. After 24 and 48 hours incubation, the diameters of the zones of inhibition were measured. The results of the disc diffusion tests showed that BA and MTA were effective on the tested microorganisms at 24 and 48 hours incubation periods. BA and MTA showed similar antimicrobial effects on C.albicans and E.coli. BA was more effective than MTA on S.mutans, E.faecalis and P.aeruginosa, however MTA was more effective than BA on S.sanguinis at 48 hours. When the time efficiency of the materials were compared, there was no statistically difference between 24 to 48 hours on E.coli, E.faecalis, S.mutans, S.sanguinis in both two groups (p> 0.05). There was statistically significant decrease 24 to 48 hours on C.albicans in BA and MTA groups and P.aeruginosa in BA group (p< 0.05). It can be concluded that although BA and MTA displayed similar antimicrobial efficacy on the tested microorganisms newly improved material BA demonstrated superior antimicrobial activity than other.

Expression analysis of efflux pump genes among drug-susceptible and multidrug-resistant Mycobacterium tuberculosis clinical isolates and reference strains.

Finding a gene or genes that are involved with multidrug resistance will be useful for finding a new target for the treatment of drug resistant tuberculosis. In this study, we aimed to compare the differences of the expression of 15 putative multidrug efflux pump genes in clinically isolated drug sensitive and multidrug resistant (MDR) Mycobacterium tuberculosis isolates, and reference strains. We found that these genes in the drug-sensitive and MDR M. tuberculosis isolates have similar rates of expressions. However, we found the expression levels of the all the genes are significantly higher in the clinical strains compared to the expression level of genes in the reference strains. In addition to this, it is found that standard strain has lower MIC value for the drugs including streptomycin and rifampin compared to the clinical isolate. We presume that the increase of the gene expression in the clinical strains is due to the exposure of antituberculosis drugs during treatment of patients, which cause constitutive expression of efflux systems, which might increase MIC levels of the major anti-tuberculosis drugs.

Identification of methicillin-resistant Staphylococcus aureus carrying an exfoliative toxin A gene encoding phage isolated from a hospitalized patient in Turkey.

From the four known isoforms of the staphylococcal exfoliative toxins (ETs), only ETA and ETB are the major causative agents. General knowledge is that the gene for ETA is located on the chromosome, whereas that for ETB is located on a large plasmid. Yoshizawa and co-workers (2000, Microbiol. Immunol. 44(3): 189-191) isolated, for the first time, a temperate phage (φETA) that carried the structural gene for ETA from an ETA-producing strain of Staphylococcus aureus. In this study, we presented eta gene encoding temperate phages isolated from methicillin-resistant S.aureus (MRSA) isolates obtained from patients in a Turkish hospital. Molecular analysis of the phage genome revealed that the eta gene is located upstream to amidase and holin genes, the same as in the φETA genome. However, partial sequence analysis of amidase and holin genes revealed polymorphic variation. In addition to polymorphic variation, restriction fragment length polymorphism (RFLP) analysis of all of the phage genomes showed that the ETA-containing phage is different from the rest of the phage genomes. The phylogenetic dendrogram of pulsed field gel electrophoresis (PFGE) analysis showed that the ETA-carrying MRSA is quite different from the rest of the MRSA strains. This is the first report showing that a MRSA strain carries an ETA-encoding phage.

[Identification of a novel lytic bacteriophage obtained from clinical MRSA isolates and evaluation of its antibacterial activity]. / Klinik MRSA Izolatlarindan Elde Edilen Yeni Bir Litik Bakteriyofajin Tanimlanmasi ve Antibakteriyel Etkisinin Degerlendirilmesi.

Multidrug-resistant bacteria particularly MRSA is well known as a worldwide problem. Since the rate of development of novel antimicrobial agents has been slowed down during the last years, there have been a need for the exploration of alternative solutions for the treatment of resistant bacterial infections. Treatment of infections by bacteriophages (phages) that specifically kill the infecting pathogen, i.e. by the process known as phage therapy, is considered as a possible approach to treat multidrug resistant bacteria. Phage treatment has also been considered to treat Staphylococcus aureus infections. This study was aimed to evaluate the antibacterial and cytotoxic activities of a new lytic phage obtained from clinical MRSA strains. This lytic phage named as f LizAnk was obtained during the phage infectivity studies performed with 13 lysogenic phages against MRSA strains. The antibacterial activity of the f LizAnk phage was determined in vitro in BHI (Brain Heart Infusion) and LB (Leuria Bertani) broths and the in vivo antibacterial activity against MRSA strains and possible cytotoxic effect against mammalian cells were tested on fibroblastic cell cultures (3T3). This study was conducted using 20 MRSA strains isolated from hospitalized patients. Identification of the isolates was performed by conventional methods and methicillin resistance was detected with oxacillin disk diffusion test and mecA gene detection by PCR. The method described by Kaneko et al. [Biosci Biotechnol Biochem 1997; 61(11): 1960-2] was used with some modifications, for induction and isolation of the phages. In vitro studies indicated that this phage killed the six different MRSA strains (in 107 cfu/ml concentrations) in 8 hours, and this powerful lytic effect was similar in both of the liquid media. In vivo studies were performed by using cell cultures prepared in microplates, and the wells have been inoculated with only phage, phage + MRSA mixture, and only MRSA. The cells were then evaluated microscopically as well as by MTT assay which detected alive cells colorimetrically, at 2nd and 24th hours. In our study, the f LizAnk phage did not cause any toxic effect on fibroblast cell cultures, in addition it was observed that the antibacterial effect of the phage against MRSA has proceeded in the cell culture. In conclusion, since the fLizAnk phage described in this study exhibited strong antibacterial activity against MRSA strains and no cytotoxic effect was detected against mammalian cells, it might be safely used alone or in a phage cocktail to treat skin infection caused by MRSA.

Evaluation of the presence of Helicobacter species in the biliary system of Turkish patients with cholelithiasis.

BACKGROUND/AIMS: Helicobacter genus and bile-resistant Helicobacter pylori are suggested to have a role in gallstone formation and epithelial cell proliferation in the gallbladder. The aim of this study was to evaluate the presence of Helicobacter species in the gallbladder tissue, bile and gallstones of Turkish patients with cholelithiasis. METHODS: Forty-seven patients with calculous cholecystitis and 3 controls were evaluated for the presence of Helicobacter spp. by culture, polymerase chain reaction, and histological and immunohistochemistry methods. RESULTS: Escherichia coli (10.6%), Enterobacter amnigenus (6.3%), Klebsiella planticola (2.1%), and Klebsiella ozaenae (2.1%) were isolated from the sample cultures of 8 patients. No other microorganisms, including H. pylori and other Helicobacter spp., were detected. Polymerase chain reaction was negative for Helicobacter spp. and H. pylori. No microorganisms resembling Helicobacter spp. were seen on the histological sections. The association between the presence of bacteria and epithelial cell proliferation index was not statistically significant (p=0.48). CONCLUSIONS: There was no association between the presence of Helicobacter spp. and development of cholelithiasis in our study group. The microorganisms found in the samples did not reveal any significant association with the underlying disease.

A new, simple, rapid test for detection of DNase activity of microorganisms: DNase Tube test.

The DNase test is a simple, economical method that has traditionally been used as a supplemental test to identify pathogenic Staphylococcus. This test also aids in the differentiation of closely-related genera within the Klebsiella-Enterobacter-Serratia division of Enterobacteriaceae and several other pathogens, including screening of C. diphtheriae. Currently DNase activity of microorganisms was tested using DNase agar plate methods. These tests have some drawbacks including the necessity of the extensive time to see the results of DNase activity of bacteria. In here, we developed a new method which is simple, rapid, inexpensive and applicable to examine DNase activity of any bacteria. In this method, simply, bacteria is added to the broth medium containing DNA and followed for the DNA degradation caused by the DNase of bacteria by running in agarose gel. This method we called DNase Tube test showed DNA degradation as fast as in half an hour depending on the DNase activity of the bacteria.

Antimicrobial effect, in vitro, of gutta-percha points containing root canal medications against yeasts and Enterococcus faecalis.

OBJECTIVE: The objective of this study was to determine the in vitro susceptibility of Enterococcus faecalis and the most prevalent Candida species as therapy-resistant microorganisms to gutta-percha points containing root canal medications. STUDY DESIGN: Gutta-percha points containing calcium hydroxide (Calcium Hydroxide Plus Points), chlorhexidine diacetate (Activ Points), or calcium hydroxide-chlorhexidine combinations (CHX/Ca Combi Points) were tested for their ability to inhibit growth of pure cultures of Candida albicans, Candida glabrata, Candida parapsilosis, Candida krusei, Candida tropicalis, Saccharomyces cerevisiae, and Enterococcus faecalis. Approximately 2 x 10(7) microorganisms per assay were suspended in diluted human serum and co-incubated with the gutta-percha points placed in Eppendorf tubes in an incubator for up to 2 weeks. A tube was removed at 1, 2, 3, 4, 7, and 14 days, and then opened and microorganism suspensions were serially diluted in a sterile 0.9% NaCl solution. Aliquots of the dilution steps were streaked onto solid medium. After incubating the plates in an incubator at 37 +/- 1 degrees C for 48 hours, CFU numbers per milliliter of suspension were calculated. RESULTS: Calcium Hydroxide Plus Points or Activ Points did not exhibit sufficient antimicrobial or anticandidal activity for Enterococcus faecalis, Candida albicans, C. glabrata, C. parapsilosis, C. krusei, or C. tropicalis within 14 days. Only Saccharomyces cerevisiae was susceptible to the calcium hydroxide or chlorhexidine diacetate containing gutta percha points. CHX/Ca Combi Points killed C. albicans, C. glabrata, C. krusei, C. tropicalis, and S. cerevisiae completely. However, E. faecalis and C. parapsilosis were resistant to CHX/Ca Combi points within 14 days. CONCLUSION: The results show the gutta percha points containing a mixture of calcium hydroxide and chlorhexidine diacetate have efficacies superior to calcium hydroxide or chlorhexidine diacetate alone against some microorganisms except E. faecalis and C. parapsilosis.

Relationship between thyroid autoimmunity and Yersinia enterocolitica antibodies.

It has previously been proposed that subclinical Yersinia enterocolitica infection may play a role in autoimmune thyroid disease (AITD). In this study, we investigated the relationship between the thyroid autoantibodies and the antibodies that produced against different serotypes of Y. enterocolitica. A total of 215 subjects were included into the study (65 newly diagnosed Graves' disease [GD], 57 Hashimoto's thyroiditis [HT], 53 nontoxic diffuse goiter [NTDG], and 40 subjects for control group [CG]). Thyroid receptor antibodies (TRAb), thyroid and agglutinating antibodies against Y. enterocolitica serotype O:3, O:5, O:8, O:9 were measured in the blood samples. The highest incidence of Y. enterocolitica antibody positivity was measured in GD (53.8% for O:3, 29.2% for O:5, 44.6% for O:8, and 40% for O:9) and followed by HT. In patients with GD, TRAb levels were also higher than in patients with HT, NTDG, and CG. There was no difference between NTDG and CG in respect to the titer levels and the positivity of both TRAb and Y. enterocolitica antibodies. There was also a weak linear correlation between TRAb level and the titer of antibodies against Y. enterocolitica antigens. It can be concluded that Y. enterocolitica infection may play a role in etiology of GD in Turkey.