Platelet-rich plasma, platelet-rich fibrin, and enamel matrix derivative for oral mucosal wound healing.

Different approaches to enhance healing of hard or soft tissues include the use of cytokines and growth factors to modify cellular behaviour. Numerous growth factors are found in autologous blood concentrates - platelet-rich plasma (PRP) and platelet-rich fibrin (PRF). Enamel matrix derivative (EMD) may improve tissue healing via amelogenins. Bilayered collagen matrix (CM) is used for soft tissue augmentation. The aim of the present study was to assess potential benefits of PRP, PRF and EMD in combination with bilayered collagen matrix or CM alone in treatment of oral mucosal defects in rabbits. Twenty-seven New Zealand white rabbits were included in this randomized controlled trial. Artificial oral mucosal defects were treated with one of these five approaches: PRP+CM, PRF+CM, EMD+CM, CM alone, or left untreated as a negative control - CO. The animals were euthanized 1 day, 7 days, or 28 days after surgery and necropsies were harvested. Histological and molecular biological analyses were performed. All defects were healed by day 28. No differences between PRP+CM, PRF+CM, CM alone and CO groups were recorded at any time point. Slower angiogenesis and a higher presence of inflammatory infiltrate were observed in the EMD+CM group 28 days after surgery. Molecular biological analyses did not reveal any statistically significant changes. In conclusion, no improvement in mucosal healing of wounds covered with a collagen membrane and PRP, PRF, or EMD was observed, compared with CM alone or untreated controls.

Genetic determinants and postorthodontic external apical root resorption in Czech children.

OBJECTIVE: Genes, involved in the modulation of inflammatory response and bone remodeling, play a role in the development of postorthodontic external apical root resorption (EARR). The aim of our study was to analyze possible associations between seven single nucleotide polymorphisms (SNPs) in interleukin-17A (IL-17), osteopontin (SPP1), purinoreceptor P2X7 (P2RX7), and tumor necrosis factor receptor superfamily member 11B (TNFRSF11B) genes and EARR in children after orthodontic treatment. SUBJECTS AND METHODS: This case-control study comprised 99 orthodontically treated patients (69 controls and 30 subjects with EARR). Genotype determinations of rs2275913, rs11730582, rs9138, rs208294, rs1718119, rs3102735, and rs2073618 were based on polymerase chain reaction using 5' nuclease TaqMan® assays. RESULTS: While no significant differences were observed in allele or genotype frequencies of all seven studied SNPs, specific haplotype of P2RX7 (rs208294 and rs1718119) modified the risk of EARR development (P < 0.05). In addition, the length of treatment with a fixed orthodontic appliance positively correlated with the presence of EARR (P < 0.05). CONCLUSIONS: Although the effect of individual SNPs studied on the EARR development was not confirmed in the Czech population, complex analysis suggested that variability in the P2RX7 gene and the length of orthodontic treatment may be important factors contributing to the etiopathogenesis of postorthodontic EARR.

[Dental abnormalities after treatment for childhood cancer]. / Dentálne abnormality po protinádorovej liecbe v detskom veku.

Childhood cancer therapy often increases the risk of dental complications, such as tooth and roots agenesis, microdontia, abnormal development of tooth enamel, increased risk of cavity and other abnormalities. In a comparison with other late adverse effects of chemotherapy, radiotherapy and hematopoietic stem cell transplantion, a relative small number of clinical stud-ies observing patients for more than two years after completion of anticancer treatment was published. In this article, we review the incidence of dental abnormalities caused by commonly used anticancer treatment modalities as well as discuss their risk factors. Early identification of high-risk patients, early detection and management of dental abnormalities and better education of patients or their guardians, may have an impact on quality of life of cancer survivors.

IL1 gene polymorphisms in relation to external apical root resorption concurrent with orthodontia.

OBJECTIVE: External apical root resorption (EARR) is permanent shortening of the end of the tooth root. It is a common clinical complication of orthodontic treatment. Polymorphisms in the interleukin 1 (IL1) gene cluster have been related to an increased EARR risk. The aim of this study was to analyze possible associations of IL1 gene variants with EARR in Czech population. SUBJECTS AND METHODS: In this case-control study, 32 patients with EARR (age 15.0 ± 4.1 years) and 74 controls (age 15.2 ± 5.3 years) were genotyped using PCR-based methods for IL1A (-889C/T), IL1B (+3953C/T), and IL1RN [IL1 receptor antagonist, variable number tandem repeat (VNTR)] gene polymorphisms. RESULTS: While no statistical significant differences in the IL1A and IL1B genotype, allele and reconstructed IL1 haplotype frequencies between patients with EARR and controls were found, marginally significant differences were observed in the frequencies of IL1RN variant (P = 0.05 for *22 genotype and P = 0.06 for a short (2) allele). In addition, significant associations between IL1RN*12, *22 genotypes and the short (2) allele and EARR were identified in the subgroup of girls (P = 0.04 and P = 0.02, P = 0.02). CONCLUSIONS: Although no significant role of IL1A (-889C/T) and IL1B (+3953C/T) variants in EARR was confirmed, IL1RN VNTR may be associated with EARR, especially in girls.

Relationship between gingivitis severity, caries experience and orthodontic anomalies in 13-15 year-old adolescents in Brno, Czech Republic.

OBJECTIVES: The aim of the present cross-sectional study was to assess oral health in adolescents selected from the ELSPAC (European Longitudinal Study of Pregnancy and Childhood) Bmo group and complete thus the ELSPAC series of studies on child general health. MATERIAL AND METHODS: Randomly selected children from the ELSPAC group (n=780) were examined clinically for dental and periodontal status, dental plaque, dental calculus and orthodontic anomalies. The following clinical parameters were assessed: DMFT score and its components, gingival index (GI), plaque index (PI) and calculus index (CSI). GI, PI and CSI were recorded on selected teeth. The presence/absence of orthodontic anomalies and their severity were recorded. ANOVA test for quantitative and XZ2 test for qualitative parameters evaluation were used. RESULTS: Mean DMFT of the group was 2.82 (SE 0.36), share of caries-free children 25.4%. Mean GI index of the cohort was 0.204 (SE 0.011), grade 0 was found in 36.9% children, grade 1 in 43.0%, and grade 2 in 19.5%. Statistical significant associations (p < 0.05) were observed in GI and DMFT, GI and DT value, GI and severity of orthodontic anomaly; significant difference was found in GI of caries-free and treated children vs. treatment need and in PI value between children with gingivitis vs healthy ones. CONCLUSION: The results demonstrated a relatively high caries experience, low level of gingival inflammation and relation between GI and DMFT, particularly in D component, and between GI and orthodontic anomalies.

Matrix metalloproteinase 8 (MMP8) gene polymorphisms in chronic periodontitis.

OBJECTIVE: Previous studies have suggested that some functional polymorphisms in the matrix metalloproteinase (MMPs) genes are associated with the risk of periodontal disease. However, to date no study has investigated MMP8 gene variants in relation to chronic periodontitis (CP). The aim of this study was to analyse polymorphisms in the MMP8 gene and their associations with microbial composition and clinical manifestation of CP. DESIGN: A total of 619 unrelated Czech subjects were included in the present study. Two polymorphisms [-799C/T (rs11225395) and +17C/G (rs2155052)] in the MMP8 gene were studied in 341 patients with CP and 278 unrelated non-periodontitis controls. Both polymorphisms were detected using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methods. Subgingival bacterial colonisation (occurrence of bacteria in subgingival pockets and gingival sulci) was investigated by a commercial semiquantitative kit in selected subjects (N=169). RESULTS: Our results showed no differences in the allele and genotype frequencies of the MMP8 -799C/T and +17C/G polymorphisms between patients with CP and controls (p>0.05). Nevertheless, the haplotype T(-799)/C(+17) was significantly more frequent in patients with CP than in controls [43.7% vs. 37.6%, p<0.05, OR=1.273 (95% CI: 1.013-1.601)]. Despite significant differences determined in the occurrence of periodontal bacteria between patients with CP and non-periodontitis controls (from p<0.000001 to p<0.05), no significant relationships between periodontal pathogens, MMP8 polymorphisms and CP were found (p>0.05). CONCLUSIONS: Although none of the investigated SNPs in the MMP8 gene was individually associated with periodontitis, specific haplotype showed association with clinical manifestation of chronic periodontitis in a Czech population.

Association of eNOS gene polymorphisms T-786C and G894T with blood pressure variability in man.

The aim of this study was to evaluate the association of single nucleotide polymorphisms (SNPs) T-786C and G894T in the gene encoding eNOS with blood pressure variability (BPV) in man. Blood pressure was recorded beat-to-beat at rest three times in periods of one week (5 min, Finapres, breathing at 0.33 Hz) in 152 subjects (19-24 years). Systolic (SBPV(0.1r)/SBPV(0.1a)) and diastolic (DBPV(0.1r)/DBPV(0.1a)) blood pressure variabilities in relative (r.u.) and absolute (mm Hg(2)/Hz) units were determined by the spectral method as spectral power at the frequency of 0.1 Hz. Genotypes of both polymorphisms were detected using polymerase chain reaction and restriction analysis using enzymes Msp I and Ban II. Significant differences were observed in BPV among genotypes of T-786C SNP (p<0.05; Kruskal-Wallis), and among haplotypes of both SNPs (p<0.05; Kruskal-Wallis) as well. In T-786C SNP, carriers of less frequent allele (CC homozygotes and TC heterozygotes) showed significantly greater SBPV(0.1r) and SBPV(0.1a) compared to TT homozygotes (Mann-Whitney; p<0.05). The G894T variant showed no significant differences, but, both SNPs were in linkage disequilibrium (D'=0.37; p<0.01). Carriers of haplotype CT/CT (CC homozygotes of -786C/T and TT homozygotes of G894T) displayed significantly greater SBPV(0.1r), SBPV(0.1a) and DBPV(0.1a) compared to carriers of other haplotype combinations (Kruskal-Wallis; p=0.015, p=0.048, and p=0.026, respectively). In conclusion, the haplotype formed by less frequent alleles of both eNOS variants was associated with increased systolic and diastolic BPV in this study.

Association of A1166C polymorphism in AT(1) receptor gene with baroreflex sensitivity.

The aim of this study was to evaluate the association of A1166C polymorphism in angiotensin II type 1 receptor (AT(1)R) gene with baroreflex sensitivity (BRS in ms/mm Hg; BRSf in mHz/mm Hg) in man. BRS and BRSf were determined by a spectral method in 135 subjects (19-26 years) at a frequency of 0.1 Hz. Genotypes were detected by means of polymerase chain reaction and restriction analysis using enzyme DdeI. We compared BRS and BRSf among genotypes of this polymorphism. The frequency of genotypes of AT(1)R A1166C polymorphism was: 45.9 % (AA, n=62), 45.9 % (AC, n=62), 8.2 % (CC, n=11). Differences in BRS (p<0.05) and BRSf (p<0.01) among genotypes of this single nucleotide polymorphism were found (Kruskal-Wallis: BRS - AA: 7.9+/-3.3, AC: 8.6+/-3.6, CC: 5.9+/-2.3 ms/mm Hg; BRSf - AA: 12.0+/-4.0, AC: 12.0+/-5.0, CC: 8.0+/-3.0 mHz/mm Hg). Compared to carriers of other genotypes (AA+AC) the homozygotes with the less frequent allele (CC) showed significantly lower BRSf (Mann-Whitney: BRSf - AA+AC: 12.0+/-4.0, CC: 8.0+/-3.0 mHz/mm Hg; p<0.01) and borderline lower BRS (BRS - AA+AC: 8.2+/-3.5, CC: 5.9+/-2.5 ms/mm Hg; p=0.07). We found a significant association of A1166C polymorphism in AT(1) receptor gene with baroreflex sensitivity. Homozygosity for the less frequent allele was associated with decreased baroreflex sensitivity.

Micro-RNAs miR125b and miR137 are frequently upregulated in response to capecitabine chemoradiotherapy of rectal cancer.

There is increasing evidence that some microRNAs change their levels in reaction to xenobiotic challenge. The aim of this study was to test the possible involvement of micro-RNAs in response to standard anticancer treatment. Tumor biopsies from 35 patients with rectal cancer before therapy and parallel tumor biopsies from 31 patients two weeks after starting preoperative capecitabine chemoradiotherapy were taken. The expression levels of single miRNA species were measured using TaqMan Micro-RNA assays after reverse transcription from isolated total RNAs. Many micro-RNAs (miR10a, miR21, miR145, miR212, miR339, miR361) responded to chemoradiotherapy in individual tumor samples, but there was profound intertumoral variability. However, other two micro-RNAs miR125b, miR137 showed a significant increase in median expression levels after starting therapy in most samples. Moreover, our results for the first time show that higher induced levels of miR125b and miR137 are associated with worse response to the therapy.

Lack of association between chronic periodontitis and the Toll-like receptor 4 gene polymorphisms in a Czech population.

BACKGROUND AND OBJECTIVE: Periodontitis is a bacterially induced chronic inflammatory disease and a major cause of tooth loss among adults. Toll-like receptors are signal molecules essential for the cellular response to bacterial cell wall components. The aim of this study was to investigate relationships between chronic periodontitis and variations in the TLR4 gene. MATERIAL AND METHODS: A total of 171 patients with chronic periodontitis and 218 unrelated controls were genotyped for the Asp299Gly (896A>G) and Thr399Ile (1196C>T) polymorphisms of the TLR4 gene. RESULTS: Both variants were in nearly complete linkage disequilibrium. No homozygotes for the less common alleles, 299Gly and 399Thr, respectively, were found. The prevalence of the Asp299Gly and the Thr399Ile heterozygotes was 5.3% and 5.0% in controls, and 7.0% and 7.0% in periodontitis patients. CONCLUSION: In conclusion, TLR4 gene polymorphisms were not significantly associated with the susceptibility to, or severity of, chronic periodontitis in our population.

Genetic risk factors for diabetic nephropathy on chromosomes 6p and 7q identified by the set-association approach.

AIMS/HYPOTHESIS: In the present study we investigated potential associations of a set of 45 single nucleotide polymorphisms (SNP) in 20 candidate genes on eight chromosomes with diabetic nephropathy (DN) in type 2 diabetes mellitus. We aimed to compare two methodological approaches suitable for analysing susceptibility to complex traits: single- and multi-locus analyses. MATERIALS AND METHODS: The study comprised a total of 647 subjects in one of three groups: diabetes with or without DN, or no diabetes. Genotypes were detected by PCR-based methodology (PCR only, PCR plus RFLP, or allele-specific PCR). Haplotypes were inferred in silico. Set association (tested using SUMSTAT software) was used for multilocus analysis. RESULTS: After correction for multiple comparisons, only one SNP, in the gene encoding the receptor of advanced glycation end products, AGER 2184A/G (gene symbol formerly known as RAGE) showed a significant association with DN (p = 0.0006) in single-locus analysis. In multi-locus analysis, six SNPs exhibited a significant association with DN: four SNPs on chromosome 6p (AGER 2184A/G, LTA 252A/G, EDN1 8002G/A and AGER -429T/C) and two SNPs on chromosome 7q (NOS3 774C/T and NOS3 E298D), omnibus p = 0.033. Haplotype analysis revealed significant differences between DN and control groups in haplotype frequencies on chromosome 6 (p = 0.0002); however, there were no significant difference in the frequencies of the NOS3 haplotypes on chromosome 7. Logistic regression analysis identified SNPs AGER 2184A/G and NOS3 774C/T, together with diabetes duration and HbA1c, as significant predictors of DN. Testing for interactions between SNPs on chromosomes 6 and 7 did not provide significant evidence for epistatic interaction. CONCLUSIONS/INTERPRETATION: Using the set-association approach we identified significant associations of several SNPs on chromosomes 6 and 7 with DN. The single- and multi-locus analyses represent complementary methods.

Intraoperative manometry of the lower esophageal sphincter pressure during laparoscopic antireflux surgery with a mechanical calibration--early results.

BACKGROUND/AIMS: Persistent postoperative dysphagia diminishes the good effect of laparoscopic anti-reflux surgery. An excessive increase of the intraoperative lower esophageal sphincter pressure (LESp) is supposed to be related to the persistent postoperative dysphagia and its knowledge could lead to the modification of the surgical technique followed by improved clinical outcomes. This study aims to describe the relation between the intraoperative LESp increase and the incidence of postoperative dysphagia and to find whether a combination of intraoperative manometry and mechanical calibration of the wrap is able to decrease the incidence of the persistent postoperative dysphagia. METHODOLOGY: The randomized, prospective, two-branch study included 39 patients suffering from symptoms of gastroesophageal reflux disease. All patients underwent pre- and postoperative manometry, 24-hour pH-metry and laparoscopic anti-reflux surgery. The intraoperative LESp was measured in the study arm only. RESULTS: A higher incidence of persistent postoperative dysphagia was revealed in patients with the intraoperative LESp increase more than 15 mmHg. This complication was not found in patients with the LESp increase under 8 mmHg with no impact on the efficacy of the surgery. The combination of the intraoperative manometry and the mechanical calibration of the wrap seems to bring the benefit only to a small number of the patients. CONCLUSIONS: According to our results, the intraoperative LESp measurement proved to be a useful supplementary method which was easy to perform, and which enables a modification of the surgical technique to decrease the incidence of the persistent postoperative dysphagia.

[Could the peroperative manometry of the oesophagus be used for prediction of dysphagia following antireflux procedures?]. / Muze být peroperacní manometrie jícnu vyuzita v predikci dysfagie po antirefluxním výkonu?

A possible development of the postoperative persisting dysphagia, which decreases the quality of life of the operated, remains the main drawback of the laparoscopic antireflux surgery. Among several variations of the antireflux surgical procedures, there is none known to completely eliminate this risk. In this study, supported by the IGA MZ CR ND 7142-3 grant, peroperative measurements of the lower oesophageal sphincter (LES) tone with a concurrent mechanical callibration of the cuff using an oesophageal tube were taken. A complete Nissen-Rossetti cuff was applied in 39 patients. Peroperative increases in the LES tone following the completion of the antireflux cuffs were monitored. The patients continued to be monitored with the aim to detect the onset of dysphagia. In the patient group with the peroperative LES tone increase exceeding 15 mmHg, significantly higher rates of prolonged dysphagia were recorded. In cases of lower LES increases, the rates of dysphagia were low and good functioning to prevent any pathological gastrooesophageal reflux was maintained. No complication with respect to the peroperative oesophageal manometry was recorded. Duration of the antireflux operation conducted with the peroperative manometry was prolonged by 4 minutes, on average. Based on the assessment of the data, the authors demonstrate that the LES tone increase on its own, does not provide for the antireflux efect of the fundoplication procedures and that the patients cannot benefit from its extremely high values. On the contrary, its high values may indicate possible risks of dysphagia in the postoperative period.

Plasminogen-activator-inhibitor-1 promoter polymorphism as a risk factor for adult periodontitis in non-smokers.

Periodontal diseases belong to the most common chronic disorders affecting mankind. Smoking and impaired plasminogen activation with hypercoagulation and fibrinolysis inhibition have been proposed as having a role in predisposition to these diseases. We investigated relationships among adult periodontitis, smoking, and a variation in the deletion/insertion (4G/5G) promoter polymorphism of the plasminogen-activator-inhibitor-1 (PAI-1) gene in 304 Caucasian subjects. An association was detected between the deletion (4G) allele (and 4G/4G genotype) and periodontitis (P = 0.0022, P(corr) < 0.01; P = 0.014, P(corr) < 0.05). A stronger association occurred in non-smokers (P = 0.00021, P(corr) < 0.01; P = 0.0024, P(corr) < 0.05) where the presence of the PAI-1 gene 4G allele appears to be one of the risk factors for periodontitis.

Genotype association of C(-735)T polymorphism in matrix metalloproteinase 2 gene with G(8002)A endothelin 1 gene with plaque psoriasis.

BACKGROUND: Excessive angiogenesis is one of the characteristic features of psoriasis. OBJECTIVE: To determine the possible genetic background of neo-angiogenesis in plaque psoriasis, frequent polymorphisms in matrix metalloproteinase 2 (MMP-2) and endothelin 1 (ET-1) genes were studied. METHODS: The case group (n = 119) included patients with plaque psoriasis, aged 44 +/- 15 years. The age of onset of psoriasis was 27 +/- 11 years. The control group (n = 184) consisted of healthy subjects without any individual history of psoriasis, aged 37 +/- 15 years. C(-735)T MMP-2 and G(8002)A ET-1 polymorphisms were determined by PCR reaction with subsequent restriction analyses. RESULTS: A significant difference in genotype distribution of C(-735)T MMP-2 between psoriatic and control patients was found (p(corr) = 0.008). Two associated genotypes (CCGG and CTGG) of the two polymorphisms were significantly less frequent in psoriatic patients (p(corr) = 0.03 and p(corr) = 0.008, respectively). CONCLUSION: The results seem to reflect a different susceptibility of MMP-2 as well as of some associated MMP-2 and ET-1 genotypes to psoriasis.

A newly identified single nucleotide polymorphism in the promoter of the matrix metalloproteinase-1 gene.

Matrix metalloproteinase-1 (MMP-1) is a member of the matrix metalloproteinase enzyme family that degrades components of the extracellular matrix. Recent studies have demonstrated several polymorphic sites in the promoter of the MMP-1 gene. A newly identified single nucleotide polymorphism (SNP) at position -519 in the promoter region of the MMP-1 gene is reported. This polymorphism consists in a guanine to adenine substitution. A linkage between polymorphisms -519A/G and -1607 1G/2G was also studied.

Gene polymorphisms (G82S, 1704G/T, 2184A/G and 2245G/A) of the receptor of advanced glycation end products (RAGE) in plaque psoriasis.

Having in mind the relationships among oxidative stress, psoriasis and common disorders, the association between polymorphisms in the gene encoding the receptor for advanced glycation end products (RAGE) and plaque psoriasis, including patients with a personal history of diabetes mellitus, cardiovascular disorders, cancer and allergy, was investigated. The allele frequencies and genotype distribution combinations of the four polymorphisms in the RAGE gene (6p21.3, G82S, 1704G/T, 2184A/G and 2245A/G) were compared in a case-control study of 272 subjects (130 patients with plaque psoriasis and 142 healthy control subjects of comparable age and sex distribution). The polymerase chain reaction with subsequent restriction analysis was used for detection of genotype variants. There was a significantly higher frequency of the 2184G allele of the 2184A/G RAGE polymorphism in psoriatic patients than in the control subjects (odds ratio 2.18, 95% CI 1.32-3.59, P=0.001). The 2184G allele occurred more often in psoriatic patients with a negative history of cardiovascular diseases (odds ratio 2.38, 95% CI 1.35-4.18, P=0.001, Pcorr=0.004), in those with a negative history of diabetes mellitus (odds ratio 2.05, 95% CI 0.1.22-3.45, P=0.004, Pcorr=0.012) and in those with a negative history of cancer (odds ratio 1.97, 95% CI 1.17-3.31, P=0.007, Pcorr=0.014) compared with the corresponding control subjects. We conclude that the 2184G allele of the RAGE gene is a significant risk factor for plaque psoriasis. The risk is associated with the non-presence of some common, especially cardiovascular, diseases in psoriatic patients.

Polymorphism 4G/5G in the plasminogen activator inhibitor-1 (PAI-1) gene is associated with IgE-mediated allergic diseases and asthma in the Czech population.

BACKGROUND: Plasminogen activator inhibitor type 1 (PAI-1) is a glycoprotein that belongs to the serine protease inhibitor superfamily and has an essential role in tissue remodeling after inflammation. Recently, a single base pair deletion/insertion (4G/5G) polymorphism of the PAI-1 gene has been associated with an increased risk of asthma in nuclear families from the UK. METHODS: The present study was thus conducted to determine the association of this polymorphism with the development of IgE-mediated asthma and other allergic diseases in the Czech population. A case-control approach was used in our study. DNA taken from subjects with clinically manifested asthma and other allergic diseases (n = 207) and from reference ethnically age-gender-matched unrelated subjects (n = 186) was examined for base deletions/insertions in the PAI-1 gene. RESULTS: A significant association (P = 0.0035) was observed between the PAI-1 promoter polymorphism and IgE-mediated allergic diseases altogether. Furthermore, the 4G allele frequency was also significantly higher in the asthmatic patients than in the control group (P = 0.0148). CONCLUSIONS: Our findings support the idea that the 4G allele of the 4G/5G polymorphism in the PAI-1 gene may be a risk factor for IgE-mediated asthma and allergic diseases.