The relevance of bacterial interactions on oral health

Dissertação de mestrado integrado em Engenharia Biomédica (área de especialização em Engenharia Clínica)

Comparison of Postprandial Lipemia between Women who are on Oral Contraceptive Methods and Those who are not

Background: Postprandial Lipemia (PPL) is a physiological process that reflects the ability of the body to metabolize lipids. Even though the influence of oral contraceptives (OC) on PPL is not known, it is a known fact that their use increases fasting lipid values. Objective: To compare the PPL between women who are on OC and those who are not. Methods: A prospective analytical study which assessed eutrophic women, aged between 18 and 28 years old, who were irregularly active and with fasting triglycerides ≤150 mg/dL. They were divided into two groups: oral contraceptive group (COG) and non-oral contraceptive group (NCOG). Volunteers were submitted to the PPL test, in which blood samples were collected in time 0 (12-hour fasting) and after the intake of lipids in times 180 and 240 minutes. In order to compare the triglyceride deltas, which reflect PPL, the two-tailed Mann-Whitney test was used for independent samples between fasting collections and 180 minutes (Δ1) and between fasting and 240 minutes (Δ2). Results: Forty women were assessed and equally divided between groups. In the fasting lipid profile, it was observed that HDL did not present significant differences and that triglycerides in COG were twice as high in comparison to NCOG. Medians of Δ1 and Δ2 presented significant differences in both comparisons (p ≤0.05). Conclusion: The results point out that women who are irregularly active and use OC present more PPL in relation to those who do not use OC, which suggests that in this population, its chronic use increases the risk of heart conditions.

Equality Impact Assessment of the Oral Health Strategy (PDF 120 KB)

The Health and Personal Social Services (Northern Ireland) Order 1972 requires the Department of Health, Social Services and Public Safety to provide or secure the provision of health services in Northern Ireland designed to promote the physical and mental health of the community through the prevention, diagnosis and treatment of illness. This includes the provision of oral health care. åÊ åÊ

North South Survey of Children's Oral Health in Ireland 2002

The health strategy in Ireland has placed great emphasis on the collection of quality information on health and its determinants, for health policy planning and evaluation. This North South survey of children's oral health provides extensive data for representative samples totaling 19,963 children and adolescents on a variety of oral diseases, conditions and related parameters. The data are nationally and internationally comparable and provide a basis for planning and evaluating oral health policy in Ireland. Click here to download the document (PDF, 700kb)

Histological and histochemical evaluation of human oral mucosa constructs developed by tissue engineering

Reconstruction of large oral mucosa defects is often challenging, since the shortage of healthy oral mucosa to replace the excised tissues is very common. In this context, tissue engineering techniques may provide a source of autologous tissues available for transplant in these patients. In this work, we developed a new model of artificial oral mucosa generated by tissue engineering using a fibrin-agarose scaffold. For that purpose, we generated primary cultures of human oral mucosa fibroblasts and keratinocytes from small biopsies of normal oral mucosa using enzymatic treatments. Then we determined the viability of the cultured cells by electron probe quantitative X-ray microanalysis, and we demonstrated that most of the cells in the primary cultures were alive and had high K/Na ratios. Once cell viability was determined, we used the cultured fibroblasts and keratinocytes to develop an artificial oral mucosa construct by using a fibrin-agarose extracellular matrix and a sequential culture technique using porous culture inserts. Histological analysis of the artificial tissues showed high similarities with normal oral mucosa controls. The epithelium of the oral substitutes had several layers, with desmosomes and apical microvilli and microplicae. Both the controls and the oral mucosa substitutes showed high suprabasal expression of cytokeratin 13 and low expression of cytokeratin 10. All these results suggest that our model of oral mucosa using fibrin-agarose scaffolds show several similarities with native human oral mucosa.

Molecular mechanisms of Trypanosoma cruzi infection by oral route

Frequent reports on outbreaks of acute Chagas' disease by ingestion of food contaminated with parasites from triatomine insects illustrate the importance of this mode of transmission. Studies on oral Trypanosoma cruzi infection in mice have indicated that metacyclic trypomastigotes invade the gastric mucosal epithelium. A key molecule in this process is gp82, a stage-specific surface glycoprotein that binds to both gastric mucin and to target epithelial cells. By triggering Ca2+ signalling, gp82 promotes parasite internalisation. Gp82 is relatively resistant to peptic digestion at acidic pH, thus preserving the properties critical for oral infection. The infection process is also influenced by gp90, a metacyclic stage-specific molecule that negatively regulates the invasion process. T. cruzi strains expressing high gp90 levels invade cells poorly in vitro. However, their infectivity by oral route varies considerably due to varying susceptibilities of different gp90 isoforms to peptic digestion. Parasites expressing pepsin-susceptible gp90 become highly invasive against target cells upon contact with gastric juice. Such is the case of a T. cruzi isolate from an acute case of orally acquired Chagas' disease; the gp90 from this strain is extensively degraded upon short period of parasite permanence in the gastric milieu. If such an exacerbation of infectivity occurs in humans, it may be responsible for the severity of Chagas' disease reported in outbreaks of oral infection.

Oral and general health-related quality of life in patients treated for oral cancer compared to control group.

BACKGROUND Health-related quality of life (HRQoL) is gaining importance as a valuable outcome measure in oral cancer area. The aim of this study was to assess the general and oral HRQoL of oral and oropharyngeal cancer patients 6 or more months after treatment and compare them with a population free from this disease. METHODS A cross-sectional study was carried out with patients treated for oral cancer at least 6 months post-treatment and a gender and age group matched control group. HRQoL was measured with the 12-Item Short Form Health Survey (SF-12); oral HRQoL (OHRQoL) was evaluated using the Oral Health Impact Profile (OHIP-14) and the Oral Impacts on Daily Performances (OIDP). Multivariable regression models assessed the association between the outcomes (SF-12, OHIP-14 and OIDP) and the exposure (patients versus controls), adjusting for sex, age, social class, functional tooth units and presence of illness. RESULTS For patients (n = 142) and controls (n = 142), 64.1% were males. The mean age was 65.2 (standard deviation (sd): 12.9) years in patients and 67.5 (sd: 13.7) years in controls. Patients had worse SF-12 Physical Component Summary scores than controls even in fully the adjusted model [β-coefficient = -0.11 (95% CI: -5.12-(-0.16)]. The differences in SF-12 Mental Component Summary were not statistically significant. Regarding OHRQoL patients had 11.63 (95% CI: 6.77-20.01) higher odds for the OHIP-14 and 21.26 (95% CI: 11.54-39.13) higher odds for OIDP of being in a worse category of OHRQoL compared to controls in the fully adjusted model. CONCLUSION At least 6 months after treatment, oral cancer patients had worse OHRQoL, worse physical HRQoL and similar psychological HRQoL than the general population.

Peut-on évaluer te risque hémorragique tors d'anticoagutation orale [Oral anticoagulation and the risk of major bleeding]

Oral anticoagulants are frequently used in clinical practice. The most important complication of oral anticoagulation is major bleeding. The incidence of major bleeding is about 2-3%/year in randomized controlled trials but may be considerably higher under real life conditions. Major bleeding risk in patients receiving oral anticoagulants depends on factors related to anticoagulation itself (intensity and quality), patient-related factors (demographic characteristics and comorbid diseases), and concomitant treatments with antiplatelet or non-steroidal anti-inflammatory drugs. The role of clinical prediction rules for major bleeding is discussed.

Santé buccale: déterminants sociaux d'un terrain majeur des inégalités [Oral health: social determinants of a health inequality]

The oral health of disadvantaged social groups is worse at all the ages than that of the favored groups. If tooth decay prevalence decreases, this disease is still unequally distributed: 20% of the children, those with the weakest socio-economic statute (SES), concentrate 60% of the decays. Edentulism strikes significantly more people with weak SES. The inequalities of oral health reflect those of general health. Evidence of the inequalities in oral health is exposed even in the developed countries. Different models of intervention are presented: risk groups identification and targeting by specific programs; oral health community approach which includes socio-economic and public health measures aiming all the population; insurance approach to be combined with the preceding ones.

Single-dose oral amoxicillin or linezolid for prophylaxis of experimental endocarditis due to vancomycin-susceptible and vancomycin-resistant Enterococcus faecalis.

Endocarditis prophylaxis following genitourinary or gastrointestinal procedures targets Enterococcus faecalis. Prophylaxis recommendations advocate oral amoxicillin (2 g in the United States and 3 g in the United Kingdom) in moderate-risk patients and intravenous amoxicillin (2 g) or vancomycin (1 g) plus gentamicin in high-risk patients. While ampicillin-resistant (or amoxicillin-resistant) E. faecalis is still rare, there is a concern that these regimens might fail against vancomycin-resistant and/or aminoglycoside-resistant isolates. The present study tested oral linezolid as an alternative. Rats with catheter-induced aortic vegetations were given prophylaxis simulating human pharmacokinetics of oral amoxicillin (2- to 3-g single dose), oral linezolid (600 mg, single or multiple oral doses every 12 h), or intravenous vancomycin (1-g single dose). Rats were then inoculated with the minimum inoculum infecting 90% of the animals (90% infective dose [ID(90)]) or with 10 times the ID(90) of the vancomycin-susceptible E. faecalis strain JH2-2 or the vancomycin-resistant (VanA phenotype) E. faecalis strain UCN41. Amoxicillin was also tested with two additional vancomycin-susceptible E. faecalis strains, 309 and 1209. Animals were sacrificed 3 days later. All the tested bacteria were susceptible to amoxicillin and gentamicin. Single-dose amoxicillin provided 100% protection against all four isolates at both the ID(90) and 10 times the ID(90). In contrast, linezolid required up to four consecutive doses to provide full protection against the vancomycin-resistant isolate. Vancomycin protected only against the vancomycin-susceptible strain. The high efficacy of single-dose oral amoxicillin suggests that this regimen could be used for prophylaxis in both moderate-risk and high-risk patients without additional aminoglycosides. Linezolid appears to be less reliable, at least against the vancomycin-resistant strain.

Specific (granulomatous) oral lesions of sarcoidosis: Report of two cases

Sarcoidosis is a multisystemic granulomatous disease of unknown etiology that usually presents with bilateral hiliar adenopathies, pulmonary infiltrations, and ocular and cutaneous lesions. The specific cutaneous lesions, or granulomatous, are produced in from 9% to 37% of patients with systemic sarcoidosis. Nevertheless, few patients have been described having specific lesions from sarcoidosis in the oral mucous membrane. We present 2 patients with systemic sarcoidosis who developed specific sarcoidosis lesions in the oral mucous membrane. The first patient presented a plaque on the tongue of a chronic nature associated with facial lupus pernio. The second patient presented a rapidly growing nodular lesion on the lower lip that was in fact the presentation sign of the disease. Although infrequent, oral lesions may constitute the first sign of systemic sarcoidosis. For this reason the oral mucous membrane needs to be explored when there is suspicion of sarcoidosis, and systemic sarcoidosis must be included in the differential diagnosis of oral granulomatous lesions.

Oral administration of the KATP channel opener diazoxide ameliorates disease progression in a murine model of multiple sclerosis

Background Multiple Sclerosis (MS) is an acquired inflammatory demyelinating disorder of the central nervous system (CNS) and is the leading cause of nontraumatic disability among young adults. Activated microglial cells are important effectors of demyelination and neurodegeneration, by secreting cytokines and others neurotoxic agents. Previous studies have demonstrated that microglia expresses ATP-sensitive potassium (KATP) channels and its pharmacological activation can provide neuroprotective and anti-inflammatory effects. In this study, we have examined the effect of oral administration of KATP channel opener diazoxide on induced experimental autoimmune encephalomyelitis (EAE), a mouse model of MS. Methods Anti-inflammatory effects of diazoxide were studied on lipopolysaccharide (LPS) and interferon gamma (IFNy)-activated microglial cells. EAE was induced in C57BL/6J mice by immunization with myelin oligodendrocyte glycoprotein peptide (MOG35-55). Mice were orally treated daily with diazoxide or vehicle for 15 days from the day of EAE symptom onset. Treatment starting at the same time as immunization was also assayed. Clinical signs of EAE were monitored and histological studies were performed to analyze tissue damage, demyelination, glial reactivity, axonal loss, neuronal preservation and lymphocyte infiltration. Results Diazoxide inhibited in vitro nitric oxide (NO), tumor necrosis factor alpha (TNF-¿) and interleukin-6 (IL-6) production and inducible nitric oxide synthase (iNOS) expression by activated microglia without affecting cyclooxygenase-2 (COX-2) expression and phagocytosis. Oral treatment of mice with diazoxide ameliorated EAE clinical signs but did not prevent disease. Histological analysis demonstrated that diazoxide elicited a significant reduction in myelin and axonal loss accompanied by a decrease in glial activation and neuronal damage. Diazoxide did not affect the number of infiltrating lymphocytes positive for CD3 and CD20 in the spinal cord. Conclusion Taken together, these results demonstrate novel actions of diazoxide as an anti-inflammatory agent, which might contribute to its beneficial effects on EAE through neuroprotection. Treatment with this widely used and well-tolerated drug may be a useful therapeutic intervention in ameliorating MS disease.

Assessment of driving capability through the use of clinical and psychomotor tests in relation to blood cannabinoids levels following oral administration of 20 mg dronabinol or of a cannabis decoction made with 20 or 60 mg Delta9-THC.

Delta(9)-Tetrahydrocannabinol (THC) is frequently found in the blood of drivers suspected of driving under the influence of cannabis or involved in traffic crashes. The present study used a double-blind crossover design to compare the effects of medium (16.5 mg THC) and high doses (45.7 mg THC) of hemp milk decoctions or of a medium dose of dronabinol (20 mg synthetic THC, Marinol on several skills required for safe driving. Forensic interpretation of cannabinoids blood concentrations were attempted using the models proposed by Daldrup (cannabis influencing factor or CIF) and Huestis and coworkers. First, the time concentration-profiles of THC, 11-hydroxy-Delta(9)-tetrahydrocannabinol (11-OH-THC) (active metabolite of THC), and 11-nor-9-carboxy-Delta(9)-tetrahydrocannabinol (THCCOOH) in whole blood were determined by gas chromatography-mass spectrometry-negative ion chemical ionization. Compared to smoking studies, relatively low concentrations were measured in blood. The highest mean THC concentration (8.4 ng/mL) was achieved 1 h after ingestion of the strongest decoction. Mean maximum 11-OH-THC level (12.3 ng/mL) slightly exceeded that of THC. THCCOOH reached its highest mean concentration (66.2 ng/mL) 2.5-5.5 h after intake. Individual blood levels showed considerable intersubject variability. The willingness to drive was influenced by the importance of the requested task. Under significant cannabinoids influence, the participants refused to drive when they were asked whether they would agree to accomplish several unimportant tasks, (e.g., driving a friend to a party). Most of the participants reported a significant feeling of intoxication and did not appreciate the effects, notably those felt after drinking the strongest decoction. Road sign and tracking testing revealed obvious and statistically significant differences between placebo and treatments. A marked impairment was detected after ingestion of the strongest decoction. A CIF value, which relies on the molar ratio of main active to inactive cannabinoids, greater than 10 was found to correlate with a strong feeling of intoxication. It also matched with a significant decrease in the willingness to drive, and it matched also with a significant impairment in tracking performances. The mathematic model II proposed by Huestis et al. (1992) provided at best a rough estimate of the time of oral administration with 27% of actual values being out of range of the 95% confidence interval. The sum of THC and 11-OH-THC blood concentrations provided a better estimate of impairment than THC alone. This controlled clinical study points out the negative influence on fitness to drive after medium or high dose oral THC or dronabinol.

Oral vitamin B12 for patients suspected of subtle cobalamin deficiency: a multicentre pragmatic randomised controlled trial.

BACKGROUND: Evidence regarding the effectiveness of oral vitamin B12 in patients with serum vitamin B12 levels between 125-200 pM/l is lacking. We compared the effectiveness of one-month oral vitamin B12 supplementation in patients with a subtle vitamin B12 deficiency to that of a placebo. METHODS: This multicentre (13 general practices, two nursing homes, and one primary care center in western Switzerland), parallel, randomised, controlled, closed-label, observer-blind trial included 50 patients with serum vitamin B12 levels between 125-200 pM/l who were randomized to receive either oral vitamin B12 (1000 μg daily, N = 26) or placebo (N = 24) for four weeks. The institution's pharmacist used simple randomisation to generate a table and allocate treatments. The primary outcome was the change in serum methylmalonic acid (MMA) levels after one month of treatment. Secondary outcomes were changes in total homocysteine and serum vitamin B12 levels. Blood samples were centralised for analysis and adherence to treatment was verified by an electronic device (MEMS; Aardex Europe, Switzerland). Trial registration: ISRCTN 22063938. RESULTS: Baseline characteristics and adherence to treatment were similar in both groups. After one month, one patient in the placebo group was lost to follow-up. Data were evaluated by intention-to-treat analysis. One month of vitamin B12 treatment (N = 26) lowered serum MMA levels by 0.13 μmol/l (95%CI 0.06-0.19) more than the change observed in the placebo group (N = 23). The number of patients needed to treat to detect a metabolic response in MMA after one month was 2.6 (95% CI 1.7-6.4). A significant change was observed for the B12 serum level, but not for the homocysteine level, hematocrit, or mean corpuscular volume. After three months without active treatment (at four months), significant differences in MMA levels were no longer detected. CONCLUSIONS: Oral vitamin B12 treatment normalised the metabolic markers of vitamin B12 deficiency. However, a one-month daily treatment with 1000 μg oral vitamin B12 was not sufficient to normalise the deficiency markers for four months, and treatment had no effect on haematological signs of B12 deficiency.