Association of CNR1 and FAAH endocannabinoid gene polymorphisms with anorexia nervosa and bulimia nervosa: evidence for synergistic effects.

Endocannabinoids modulate eating behavior; hence, endocannabinoid genes may contribute to the biological vulnerability to eating disorders. The rs1049353 (1359 G/A) single nucleotide polymorphism (SNP) of the gene coding the endocannabinoid CB1 receptor (CNR1) and the rs324420 (cDNA 385C to A) SNP of the gene coding fatty acid amide hydrolase (FAAH), the major degrading enzyme of endocannabinoids, have been suggested to have functional effects on mature proteins. Therefore, we explored the possibility that those SNPs were associated to anorexia nervosa and/or bulimia nervosa. The distributions of the CNR1 1359 G/A SNP and of the FAAH cDNA 385C to A SNP were investigated in 134 patients with anorexia nervosa, 180 patients with bulimia nervosa and 148 normal weight healthy controls. Additive effects of the two SNPs in the genetic susceptibility to anorexia nervosa and bulimia nervosa were also tested. As compared to healthy controls, anorexic and bulimic patients showed significantly higher frequencies of the AG genotype and the A allele of the CNR1 1359 G/A SNP. Similarly, the AC genotype and the A allele of the FAAH cDNA 385C to A SNP were significantly more frequent in anorexic and bulimic individuals. A synergistic effect of the two SNPs was evident in anorexia nervosa but not in bulimia nervosa. Present findings show for the first time that the CNR1 1359 G/A SNP and the FAAH cDNA 385C to A SNP are significantly associated to anorexia nervosa and bulimia nervosa, and demonstrate a synergistic effect of the two SNPs in anorexia nervosa.

Tetracycline fibres used to control bacterial infection during guided tissue regeneration (GTR).

AIMS: The colonization of suspected periodontal pathogens during the healing of periodontal defects treated by guided tissue regeneration (GTR) with e-PTFE membranes and tetracycline fibers was investigated. METHODS: Fifteen patients, each with one pair of angular periodontal bone defects of comparable size and morphology were recruited for the study. In a matched-pair study design, the test defects were treated with e-PTFE membranes in combination with tetracycline fibers, while control defects were treated with e-PTFE membranes alone. Microbiological specimens were taken from control as well as from test sites preoperatively (T0), intraoperatively (T1), two weeks after surgery (T2) and from membranes at time of removal (T3). Cultural methods were used to identify the following species: Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi), Fusobacterium nucleatum (Fn) and Actinobacillus actinomicetemcomitans (Aa). RESULTS: At baseline and T1, none of the suspected periodontal pathogens were detected at test or control sites. Levels of P. intermedia and F. nucleatum, as mean percentages of total culturable microflora, were detected at levels significantly higher in control sites than test sites at times T2 and T3. CONCLUSIONS: Findings from this study suggest that e-PTFE membranes are frequently colonized by periodontal pathogens, and that bacterial colonization of healing sites after GTR procedures can be kept under control with a controlled delivery system releasing tetracycline.

[Bacterial virulence in the etiology of periodontal diseases]. / La virulenza batterica nella etiologia delle malattie parodontali.

Strong relationships have been very often described between various form of periodontal disease (PD) and certain bacterial species, so that nowadays periodontal disease is recognized as an infectious disease. Destruction of periodontal supporting tissues happens as a response to very intricate host-parasite interactions. When the clinician will be able to fully understand and identify such phenomena it would be possible to succeed in a properly diagnosis and control of the active phase of periodontal disease. The first step in such a direction would be to analyze the common characteristic of some bacterial species, the so called suspected periodontopathogens. Such species namely Gram-negative, associated with the outbreak of periodontal disease have in common the capacity to disrupt the integrity of the host defences by means of the so called virulence factors. These factors may enhance the bacterial colonization or may interfere with the host response that ultimately results in periodontal support breakdown. The present review focuses on the virulence factors of the main suspected periodontopathogens evaluating the effects on the host immune response and directly on the periodontal tissues.

Bacterial colonisation during GTR treatment. A longitudinal analysis.

UNLABELLED: The purpose of the present study was to evaluate the long-term biological and clinical effects of a controlled delivery system releasing tetracyclines during the healing of interproximal periodontal defects treated by the technique of guided tissue regeneration (GTR) using e-PTFE membranes. METHODS: Fifteen patients, each with two comparable interproximal periodontal defects, underwent surgical treatment with e-PTFE membranes in conjunction with tetracycline fibres at the test site and e-PTFE membranes alone at the control site. Microbiological specimens were taken from each site treated at baseline (T0) and one year after surgery (T4). Plaque index (PI), gingival index (GI), pocket depth at probing (PD) and attachment level at probing (PAL) were recorded at baseline (T0) and one year after surgery (T4). The presence of selected pathogenic microbial species, Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi), Fusobacterium Nucleatum (Fn) and Actinobaccillus Actinomicetemcomitans (Aa), was investigated and these species were identified by cultural methods. RESULTS: No statistically significant difference in the level of periodontal pathogens was detected between the test and control sites at time T4. Likewise, no significant clinical difference between the test site and the control site was detected at time T4. CONCLUSIONS: The results suggest that tetracycline fibres used in conjunction with e-PTFE membranes do not provide and further clinical and microbiological improvement or effect the healing of periodontal defects one year after GTR treatment.

[Periodontal regeneration: the use of polypeptide growth factors]. / Rigenerazione parodontale: utilizzo dei fattori di crescita polipeptidici.

Polypeptide growth factors are a class of potent natural biologic mediators which regulate many of the activities of wound healing including cell proliferation, migration and metabolism. Periodontal regeneration is thought to require the migration and proliferation of periodontal ligament cells on the root surface. In fact, repopulation of the detached root surface by cells from periodontal ligament (PDL) is a prerequisite for new attachment formation. Many studies suggested that Polypeptide Growth Factors (PGF) such as Insulin-like Growth Factor I (IGF-I), Platelet Derived Growth Factor (PDGF), Transforming Growth Factor B (TGF-B), Epidermal Growth Factor (EGF), are important mediators of cellular events in wound healing. Studies in vitro analysed the mitogenic effects determined on periodontal ligament cells by growth factors using (3H) Thymidine incorporation during DNA synthesis. The results suggested that recombinant human PDGF and IGF-I stimulate the proliferation of PDL fibroblastic cells and the combination of these growth factors showed a synergistic effect revealing the highest mitogenic effect among all individual growth factors as well as any combination of the growth factors tested. Furthermore these studies demonstrated that rh-PDGF and IGF-I stimulate chemotaxis of PDL fibroblastic cells, and supported a role for TGF-B as a regulator of the mitogenic response to PDGF in these cells. Other studies in vivo showed periodontal tissues regeneration introducing mixtures of recombinant human platelet derived growth factor and insulin-like growth factor into lesions of experimentally induced periodontitis in beagle dogs and monkeys.(ABSTRACT TRUNCATED AT 250 WORDS)