Efficacy of doxycycline release collagen membrane on surgically created and contaminated defects in rat tibiae: A histopathological and microbiological study.

BACKGROUND: The effects of systemic antibiotics on controlling infective pathogens after guided bone regeneration(GBR) procedures especially in membrane exposures are limited. However, local administrations of antibiotics are rare in GBR techniques. AIM: The aim of this study was to investigate the osteogenesis potential and the antibacterial effect of a doxycycline releasing collagen membrane in surgically created and contaminated defects in rat tibiae. MATERIAL AND METHODS: Defects were created in 20 rats that were randomly divided in to two groups: control group (defect contaminated by Porphyromonas gingivalis, filled with bone graft and covered by collagen membrane); test group (defect contaminated by P. gingivalis filled with bone graft and covered by collagen membrane containing 1mg/cm(2) doxycycline. Animals were sacrificed post surgically on the 14th day for microbiologic evaluation and on the 28th day for histopathological evaluation. RESULTS: The degree of osteogenesis in the test group was seen to be significantly higher than control group (p: 0.011; p<0.05). Furthermore in test group, no bacterial growth was observed. The bacteria counts were determined between 1×104 and 268×104CFU/g with a median of 1.32×104 for control group. CONCLUSIONS: Within the limitations of this study, the results of the present study suggests that the use of a doxycycline releasing membrane has a positive effect on contaminated GBR procedures for limiting P. gingivalis infections leading to bone formation following GBR procedures in a rat model.

Expression Profiles of TGF-ß and TLR Pathways in Porphyromonas gingivalis and Prevotella intermedia Challenged Osteoblasts.

BACKGROUND: The presence of certain oral pathogens at implant sites can hinder the osseointegration process. However, it is unclear how and by what microorganisms it happens. OBJECTIVES: This study investigated whether the presence of oral pathogens of Porphyromonas gingivalis and Prevotella intermedia individually, play a role in the failure of bone formation by determining the expression profiles of Transforming Growth Factor Beta (TGF-ß/Bone Morphogenic Protein (BMP) and Toll-Like Receptor (TLR) pathways in challenged osteoblasts. MATERIALS AND METHODS: Cell viability of P. gingivalis and P. intermedia challenged osteoblasts were determined by WST assay. Changes in osteoblast morphology and inhibition of mineralization were observed by Scanning Electron Microscopy (SEM) and Von Kossa staining, respectively. Expression of TGF-ß and TLR pathway genes on challenged cells were identified by RT profiler array. Both P. gingivalis and P. intermedia challenges resulted in reduced viability and mineralization of osteoblasts. RESULTS: Viability was reduced to 56.8% (P. gingivalis) and 52.75% (P. intermedia) at 1000 multiplicity. Amongst 48 genes examined, expressions of BMPER, SMAD1, IL8 and NFRKB were found to be highly upregulated by both bacterial challenges (Fold Change > 4). CONCLUSIONS: P. gingivalis and P. intermedia could play a role in implant failure by changing the expression profiles of genes related to bone formation and resorption.

Early childhood caries is associated with genetic variants in enamel formation and immune response genes.

Early childhood caries (ECC) is a chronic, infectious disease that affects the primary dentition of young children. It is the result of an imbalance of risk factors and protective factors that influence the disease. The aim of this study was to assess genetic and environmental factors that may contribute to ECC. Two hundred and fifty-nine unrelated children were evaluated using a cross-sectional design. Data on oral habits were obtained through a questionnaire, and caries experience data were collected by clinical examination. Twenty-three markers in 10 genes were studied. Genotyping of the selected polymorphisms was carried out by real-time PCR. Regression analyses were performed comparing individuals with and without caries experience. Of 259 subjects, 123 were caries free. The genotype TT in ALOX15 (rs7217186) was a risk factor for ECC, whereas the genotypes GG in ENAM (rs1264848), AG and GG in KLK4 (rs198968), CT in LTF (rs4547741), and GG in TUFT1 (rs3790506) were protective for EEC. In conclusion, environmental factors and gene interactions can act as protective or risk factors for ECC. These factors together contribute to the presence and severity of the disease.

Serum interleukin 17 levels in patients with Crohn's disease: real life data.

UNLABELLED: The aim of this study was to investigate serum IL17 levels in patients with Crohn's disease (CD) and to investigate the relationship between serum IL17 levels with disease activity. METHODS: Fifty patients with CD and sex- and age-matched 40 healthy controls were included in the study. The serum IL17 levels, complete blood count, blood chemistry, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) levels were measured, and Crohn's disease activity was calculated using Crohn's disease activity index (CDAI). RESULTS: The mean serum IL17 level of CD patients did not differ from those of healthy controls (P > 0.05). There was no difference between the mean serum IL levels of active CD patients and of quiescent CD patients (P > 0.05). However, the mean IL17 level of active patients was lower than of control subjects (P = 0.02). Serum IL17 was not correlated with inflammatory markers (ESR, CRP, white blood count, platelet count, and albumin) and CDAI. CONCLUSIONS: Peripheral blood serum IL17 levels of CD patients were not higher than of healthy controls, and also, serum IL17 level was not correlated with clinical disease activity. Peripheral IL17 measurement is not a useful tool for detecting and monitoring Crohn's disease which is understood to have complex etiopathogenesis.

ABCB1 C3435T and CYP2C19*2 polymorphisms in a Palestinian and Turkish population: A pharmacogenetic perspective to clopidogrel.

Clopidogrel is an antiplatelet drug used to prevent recurrent ischemic events after acute coronary syndrome and/or coronary stent implantation. Single nucleotide polymorphisms (SNPs) such as CYP2C19*2 and ABCB1 C3435T have been found to play a role in different individual responses to clopidogrel. Since the prevalence of these SNPs is generally known to differ from one population to another, the aim of this study was to examine their prevalence in both a Palestinian and Turkish population. One hundred unrelated Palestinian subjects and 100 unrelated Turkish subjects were analyzed for CYP2C19*2 and ABCB1 C3435T polymorphisms by the amplification refractory mutation system (ARMS). Results showed an ABCB1 3435 T allele frequency of 0.46 (95% CI 0.391 to 0.529) in the Palestinian sample and 0.535 (95% CI 0.4664 to 0.6036) in the Turkish sample. CYP2C19*2 allele frequency was 0.095 (95% CI 0.0558 to 0.134) in the Palestinian sample and 0.135 (95% CI 0.088 to 0.182) in the Turkish sample. Our results provide information about the prevalence of the polymorphisms related to clopidogrel response in both the Palestinian and Turkish populations, in order to improve the safety and efficacy of clopidogrel through use of genetically guided, individualized treatment. The prevalence of these clinically significant alleles shed light on the importance of testing them before prescribing clopidogrel.

An association study of functional polymorphic genes IRF-1, IFNGR-1, and IFN-γ with disease progression, aspartate aminotransferase, alanine aminotransferase, and viral load in chronic hepatitis B and C.

BACKGROUND: Investigational approaches based on genome-wide association studies have proven useful in identifying genetic predictors for many diseases, including susceptibility to chronic hepatitis B and C. In these studies, the majority of genetic variants that have shown a positive association have been identified in genes involved in the immune response. In this study IFN-γ, IFNGR-1, and IRF-1 genes were analyzed for their role in susceptibility to the development of chronic hepatitis B and chronic hepatitis C in a Turkish population. METHODS: Polymorphic genes IRF-1 (-410, -388), IFNGR-1 (-56, -611), and IFN-γ (+874) were analyzed in a total of 400 individuals: 100 chronic hepatitis B patients, 100 hepatitis B carriers, 100 chronic hepatitis C patients, and 100 healthy controls. A single base primer extension assay was used. Correlations between genes and gender, viral load, and aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels were also investigated. RESULTS: The IRF-1 gene at positions -388 and -410 were observed to be candidate gene markers for susceptibility to the development of chronic hepatitis B and C (p<0.05). IFN-γ +874 and IFNGR-1 (-56 and -611) correlated with chronic hepatitis B but not chronic hepatitis C. Correlation of functional genotype with viral load and AST and ALT levels revealed an association of IFN-γ +874 and IFNGR-1 -611 with chronic hepatitis C and IFN-γ +874 with viral load and chronic hepatitis B (p<0.05). CONCLUSIONS: Findings suggest that IFN-γ (+874), IRF-1 (-410, -388), and IFNGR-1 (-56, -611) are candidate gene markers for determining patient susceptibility to the development of chronic hepatitis B and C.

A comparative study of the role of cytokine polymorphisms interleukin-10 and tumor necrosis factor alpha in susceptibility to implant failure and chronic periodontitis.

PURPOSE: The presence of pathogenic microorganisms associated with both chronic periodontitis and implant failure can induce a host immune response. The type of response is determined by an individual's genetic makeup. The aim of this study was to investigate the genetic relationship between interleukin-10 (IL-10) and tumor necrosis factor alpha (TNF-α) polymorphisms and patient susceptibility to chronic periodontitis or implant failure and to compare their immunogenetic functions. MATERIALS AND METHODS: This study recruited subjects according to clinical diagnostic criteria for failing implants, chronic periodontitis, healthy implants, and healthy controls. Human DNA from buccal swabs was analyzed by amplification refractory mutation system-polymerase chain reaction and agarose gel electrophoresis performed for gene polymorphisms of IL-10 (IL-10, IL-1082, IL-819, and IL-592) and TNF-α (TNF-α-308). Differences in the polymorphisms between test groups and healthy controls were assessed by Pearson chi-square test. RESULTS: A total of 95 patients (16 failing implants, 22 chronic periodontitis, 23 healthy implants, and 34 healthy controls) were enrolled in this study. No significant association of IL-10 and TNF-α alleles, genotypes, or haplotypes were observed in chronic periodontitis or failing implant patients (P > .005). However, both patient groups showed highly similar frequencies of alleles, genotypes, and haplotypes (P > .99). CONCLUSION: This study found no significant association of either IL-10 or TNF-α genes in the susceptibility to the development of chronic periodontitis or implant failure.

Interleukin 10 genotype as a risk factor for sudden infant death syndrome: determination of IL-10 genotype from wax-embedded postmortem samples.

In a previous study an association was shown between SIDS and an interleukin-10 (IL-10) genotype. That study was carried out on frozen, unfixed tissue samples, but these are difficult to obtain. Fixed samples used for pathological examination are available. The purpose of this study was to extend the previous work by establishing methods to extract and genotype DNA from fixed, wax-embedded tissues specimens and to use the results to seek confirmation of the association between IL-10 genotype and SIDS in a larger collection of SIDS babies. Using an amplification refractory mutation system-polymerase chain reaction method, a total of 38 infants were genotyped for IL-10 alleles and compared with controls. There was a significant association between the IL-10 -592*A allele and SIDS, consistent with the earlier findings. This study lends support to the hypothesis that IL-10 genotype is related to the susceptibility of babies to SIDS.

The effects of an immediately pre-surgical chlorhexidine oral rinse on the bacterial contaminants of bone debris collected during dental implant surgery.

Dental implant surgery produces bone debris that can be used in the "simultaneous augmentation" technique. Although this debris is contaminated with oral bacteria, a stringent aspiration protocol has been shown to reduce the levels of contamination. Chlorhexidine mouthrinse is a well-proven antibacterial rinse that has been shown to reduce infectious complications associated with dental implants. This study examined the effect of pre-operative rinsing with a 0.1% chlorhexidine digluconate mouthrinse on the bacterial contaminants present in collected bone debris bone (CBD). Twenty partially edentate patients were randomly allocated into equal groups and underwent bone collection using the Frios Bone Collector (FBC) during the insertion of two dental implants. In group T a pre-operative chlorhexidine rinse was used, whilst in group C sterile water was used. For both groups, a stringent bone collection protocol was used. Bone samples were immediately transported for microbial analysis. Colonial and microscopic morphology, gaseous requirements and identification kits were utilised for identification of the isolated microbes. Thirty-nine species were identified including a number associated with disease, in particular Actinomyces odontolyticus, Clostridium bifermentans, Prevotella intermedia, and Propionibacterium propionicum. Samples from group T (chlorhexidine mouthrinse) yielded significantly fewer organisms (P < 0.001) than in group C (sterile water mouthrinse). Gram-positive cocci dominated the isolates from both groups. It is concluded that if bone debris is to be used for the purpose of immediate simultaneous augmentation, a preoperative chlorhexidine mouthrinse should be utilised in conjunction with a stringent aspiration protocol to reduce further the bacterial contamination of CBD.