Oral health behaviour, conditions and care among dentate elderly patients in Lithuania: preventive aspects

The present cross-sectional study aimed to assess oral health behaviour, dental and periodontal conditions, dental care, and their relationships among elderly dentate patients in Lithuania. The target population in the study were dentate patients aged 60 and older attending public dental services in Kedainiai, Lithuania. The data collection took place between the autumn of 1999 and the winter of 2001. Data were collected by means of a self-administered questionnaire for all (n=174) and a clinical examination targeting about half of the subjects (n=100). The questionnaire inquired about oral health behaviour, the life-first and also the most recent dental treatments, sources on and self-assessed knowledge of oral self-care, a self-reported number of teeth, and socio-demographic information. The clinical examination included basic dental and periodontal conditions. A total of 82 women and 92 men completed the questionnaire; their mean age was 69.2 and their average number of teeth was 16.2 (CI 95% 15.4-17.1). In all, 25% had 21 or more teeth and 32% indicated wearing removable dentures. The oral health behaviour, the participants reported, was poor: 30% reported twice daily toothbrushing, 57% responded that they always use fluoride toothpaste, 19% indicated daily interdental cleaning, nearly all said they take sugar in their coffee and tea, and 30% indicated going for check-ups. As the main source of information on oral self-care, the subjects indicated health professionals (82%), followed by social contacts (72%), broadcasted media (58%), and printed media (42%). A total of 34% assessed their knowledge of oral self-care as good, and their self-assessed knowledge correlated (r=0.52) with professional guidance they had received about oral self-care. In their most recent treatment, conservative (39%) and non-conservative (34%) treatments dominated, and preventive ones were the least reported (7%). Regarding guidance in oral self-care, 54% reported having received such about toothbrushing, 32% about interdental cleaning, and 33% had been given visual information. Clinical examinations revealed the presence of plaque, calculus, bleeding on probing and deepened pockets in all of the subjects; 70% of the subjects were diagnosed with pockets of 6mm and deeper, 94% with caries, and 73% with overhangs of restorations. Those subjects assessing their knowledge of oral self-care as good and reporting a higher intensity of guidance in oral self-care as received, indicated practicing the recommended oral self-care more frequently. Twice daily toothbrushing was associated with good self-assessed knowledge of oral self-care (OR 4.1, p<0.001) and a university education (OR 5.6, p<0.001). Those subjects with better oral health behaviour had a greater number of teeth. Having 21 or more teeth was associated with good self-assessed knowledge of oral self-care (OR 4.1, p=0.03). Better periodontal conditions were associated with a higher frequency of toothbrushing. The presence of periodontal pockets of 6mm and deeper was associated with the level of self-assessed knowledge of oral self-care being below good (OR=3.0, p=0.04) and the level of dental cleanliness being poor (OR=2.7, p=0.02). To conclude, oral health behaviour and conditions call for improvement in elderly subjects in Lithuania. To improve the oral health of their elderly dentate patients, dentists should apply all the available tools of chair-side prevention and active guidance. The latter would be an effective means of updating the knowledge of oral self-care and supporting recommended oral health behaviour. A preventive approach should be strongly emphasized in countries with limited resources for oral health care, such as Lithuania. Author’s address: Sonata Vyšniauskaite, Department of Oral Public Health, Institute of Dentistry, University of Helsinki, P.O.Box 41, FI-00014 Helsinki, Finland. E-mail: sonata.vysniauskaite@helsinki.fi

Some aspects of multilevel load-frequency control of a power system

The application of multilevel control strategies for load-frequency control of interconnected power systems is assuming importance. A large multiarea power system may be viewed as an interconnection of several lower-order subsystems, with possible change of interconnection pattern during operation. The solution of the control problem involves the design of a set of local optimal controllers for the individual areas, in a completely decentralised environment, plus a global controller to provide the corrective signal to account for interconnection effects. A global controller, based on the least-square-error principle suggested by Siljak and Sundareshan, has been applied for the LFC problem. A more recent work utilises certain possible beneficial aspects of interconnection to permit more desirable system performances. The paper reports the application of the latter strategy to LFC of a two-area power system. The power-system model studied includes the effects of excitation system and governor controls. A comparison of the two strategies is also made.

Aspects of tautomerism 9-solvolysis of normal and pseudo phthaloyl chlorides

Solvolysis of normal and pseudo phthaloyl chlorides in aqueous acetone and in aqueous dioxane has revealed that the former solvolyses about hundred-fold faster than the latter. Contrary to the accepted belief, there is no evidence for equilibrium between the normal and the pseudo forms of phthaloyl chloride, under a variety of conditions.

Pharmacogenetic Variation at CYP2D6, CYP2C9, and CYP2C19: Population Genetic and Forensic Aspects

Pharmacogenetics deals with genetically determined variation in drug response. In this context, three phase I drug-metabolizing enzymes, CYP2D6, CYP2C9, and CYP2C19, have a central role, affecting the metabolism of about 20-30% of clinically used drugs. Since genes coding for these enzymes in human populations exhibit high genetic polymorphism, they are of major pharmacogenetic importance. The aims of this study were to develop new genotyping methods for CYP2D6, CYP2C9, and CYP2C19 that would cover the most important genetic variants altering the enzyme activity, and, for the first time, to describe the distribution of genetic variation at these loci on global and microgeographic scales. In addition, pharmacogenetics was applied to a postmortem forensic setting to elucidate the role of genetic variation in drug intoxications, focusing mainly on cases related to tricyclic antidepressants, which are commonly involved in fatal drug poisonings in Finland. Genetic variability data were obtained by genotyping new population samples by the methods developed based on PCR and multiplex single-nucleotide primer extension reaction, as well as by collecting data from the literature. Data consisted of 138, 129, and 146 population samples for CYP2D6, CYP2C9, and CYP2C19, respectively. In addition, over 200 postmortem forensic cases were examined with respect to drug and metabolite concentrations and genotypic variation at CYP2D6 and CYP2C19. The distribution of genetic variation within and among human populations was analyzed by descriptive statistics and variance analysis and by correlating the genetic and geographic distances using Mantel tests and spatial autocorrelation. The correlation between phenotypic and genotypic variation in drug metabolism observed in postmortem cases was also analyzed statistically. The genotyping methods developed proved to be informative, technically feasible, and cost-effective. Detailed molecular analysis of CYP2D6 genetic variation in a global survey of human populations revealed that the pattern of variation was similar to those of neutral genomic markers. Most of the CYP2D6 diversity was observed within populations, and the spatial pattern of variation was best described as clinal. On the other hand, genetic variants of CYP2D6, CYP2C9, and CYP2C19 associated with altered enzymatic activity could reach extremely high frequencies in certain geographic regions. Pharmacogenetic variation may also be significantly affected by population-specific demographic histories, as seen within the Finnish population. When pharmacogenetics was applied to a postmortem forensic setting, a correlation between amitriptyline metabolic ratios and genetic variation at CYP2D6 and CYP2C19 was observed in the sample material, even in the presence of confounding factors typical for these cases. In addition, a case of doxepin-related fatal poisoning was shown to be associated with a genetic defect at CYP2D6. Each of the genes studied showed a distinct variation pattern in human populations and high frequencies of altered activity variants, which may reflect the neutral evolution and/or selective pressures caused by dietary or environmental exposure. The results are relevant also from the clinical point of view since the genetic variation at CYP2D6, CYP2C9, and CYP2C19 already has a range of clinical applications, e.g. in cancer treatment and oral anticoagulation therapy. This study revealed that pharmacogenetics may also contribute valuable information to the medicolegal investigation of sudden, unexpected deaths.

Noise sensitivity medical, psychological and genetic aspects

Noise can be defined as unwanted sound. It may adversely affect the health and well-being of individuals. Noise sensitivity is a personality trait covering attitudes towards noise in general and a predictor of noise annoyance. Noise sensitive individuals are more affected by noise than less sensitive individuals. The determinants and characteristics related to noise sensitivity are rather poorly known. The risk of health effects caused by noise can be hypothesized to be higher for noise sensitive individuals compared to those who are not noise sensitive. A cardiovascular disease may be an example of outcomes. The general aim of the present study was to investigate the association of noise sensitivity with specific somatic and psychological factors, including the genetic component of noise sensitivity, and the association of noise sensitivity with mortality. The study was based on the Finnish Twin Cohort of same-sex twin pairs born before 1958. In 1988 a questionnaire was sent to twin pairs discordant for hypertension. 1495 individuals (688 men, 807 women) aged 31 88 years replied, including 573 twin pairs. 218 of the subjects lived in the Helsinki Metropolitan Area. Self-reported noise sensitivity, lifetime noise exposure and hypertension were obtained from the questionnaire study in 1988 and other somatic and psychological factors from the questionnaire study in 1981 for the same individuals. In addition, noise map information (1988 1992) from the Helsinki Metropolitan Area and mortality follow-up 1989 2003 were used. To evaluate the stability and validity of noise sensitivity, a new questionnaire was sent in 2002 to a sample of the subjects who had replied to the 1988 questionnaire. Of all subjects who had answered the question on noise sensitivity, 38 % were noise sensitive. Noise sensitivity was independent of noise exposure levels indicated in noise maps. Subjects with high noise sensitivity reported more transportation noise exposure than subjects with low noise sensitivity. Noise sensitive subjects reported transportation noise exposure outside the environmental noise map areas almost twice as often as non-sensitive subjects. Noise sensitivity was associated with hypertension, emphysema, use of psychotropic drugs, smoking, stress and hostility, even when lifetime noise exposure was adjusted for. Monozygotic twin pairs were more similar with regards noise sensitivity than dizygotic twin pairs, and quantitative genetic modelling indicated significant familiality. The best fitting genetic model provided an estimate of heritability of 36 %. Follow-up of subjects in the case-control study showed that cardiovascular mortality was significantly increased among noise sensitive women, but not among men. For coronary heart mortality the interaction of noise sensitivity and lifetime noise exposure was statistically significant in women. In conclusion, noise sensitivity has both somatic and psychological components. It does aggregate in families and probably has a genetic component. Noise sensitivity may be a risk factor for cardiovascular mortality in women.

Molecular and epidemiological aspects of Streptococcus pyogenes disease in Finland: Severe infections and bacterial, non-necrotizing cellulitis

Streptococcus pyogenes (group A streptococcus) is an important human pathogen, causing a wide array of infections ranging in severity. The majority of S. pyogenes infections are mild upper respiratory tract or skin infections. Severe, invasive infections, such as bacteraemia, are relatively rare, but constitute a major global burden with a high mortality. Certain streptococcal types are associated with a more severe disease and higher mortality. Bacterial, non-necrotizing cellulitis and erysipelas are localised infections of the skin, and although they are usually not life-threatening, they have a tendency to recur and therefore cause substantial morbidity. Despite several efforts aimed at developing an effective and safe vaccine against S. pyogenes infections, no vaccine is yet available. In this study, the epidemiology of invasive S. pyogenes infections in Finland was described over a decade of national, population-based surveillance. Recent trends in incidence, outcome and bacterial types were investigated. The beta-haemolytic streptococci causing cellulitis and erysipelas infections in Finland were studied in a case-control study. Bacterial isolates were characterised using both conventional and molecular typing methods, such as the emm typing, which is the most widely used typing method for beta-haemolytic streptococci. The incidence of invasive S. pyogenes disease has had an increasing trend during the past ten years in Finland, especially from 2006 onwards. Age- and sex-specific differences in the incidence rate were identified, with men having a higher incidence than women, especially among persons aged 45-64 years. In contrast, more infections occurred in women aged 25-34 years than men. Seasonal patterns with occasional peaks during the midsummer and midwinter were observed. Differences in the predisposing factors and underlying conditions of patients may contribute to these distinctions. Case fatality associated with invasive S. pyogenes infections peaked in 2005 (12%) but remained at a reasonably low level (8% overall during 2004-2007) compared to that of other developed countries (mostly exceeding 10%). Changes in the prevalent emm types were associated with the observed increases in incidence and case fatality. In the case-control study, acute bacterial non-necrotizing cellulitis was caused predominantly by Streptococcus dysgalactiae subsp. equisimilis, instead of S. pyogenes. The recurrent nature of cellulitis became evident. This study adds to our understanding of S. pyogenes infections in Finland and provides a basis for comparison to other countries and future trends. emm type surveillance and outcome analyses remain important for detecting such changes in type distribution that might lead to increases in incidence and case fatality. Bacterial characterisation serves as a basis for disease pathogenesis studies and vaccine development.

Aspects of tautomerism. 13. Alkaline hydrolysis of .gamma.-, .delta.-, and .epsilon.-keto esters and their desoxy analogs. Geometrical constraints on keto participation

The rates of alkaline hydrolysis of methyl &benzoylpropionate (I), methyl y-benzoylbutyrate (11) and methyll6-benzoylvalerate (In) decrease in the order I > I1 > III. Keto participation is the predominant pathway in the case of y-keto esters. Evidence has also been obtained for keto participation in the case of 6-keto esters, whereas no such evidence is available in the case of r-keto esters studied.

New aspects of the diagnosis of Helicobacter pylori infection

Aims: Helicobacter pylori infection, although the prevalence is declining in Western world, is still responsible for several clinically important diseases. None of the diagnostic tests is perfect and in this study, the performance of three stool antigen tests was assessed. In areas of high H. pylori prevalence, the definition of patients with the greatest benefit from eradication therapy may be a problem; the role of duodenal gastric metaplasia in categorizing patients at risk for duodenal ulcer was evaluated in this respect. Whether persistent chronic inflammation and elevated H. pylori antibodies after successful eradication are associated with each other or with atrophic gastritis, a long term sequelae of H. pylori infection, were also studied. Patients and methods: The three stool antigen tests were assessed in pre- and post-eradication settings among 364 subjects in two studies as compared to the rapid urease test (RUT), histology, culture, the 13C-urea breath test (UBT) and enzyme immunoassay (EIA) based H. pylori serology. The association between duodenal gastric metaplasia with duodenal ulcer was evaluated in a retrospective study including 1054 patients gastroscopied due to clinical indications and 154 patients previously operated for duodenal ulcer. The extent of duodenal gastric metaplasia was assessed from histological specimens in different patient groups formed on the basis of gastroscopy findings and H. pylori infection. Chronic gastric inflammation (108 patients) and H. pylori antibodies and serum markers for atrophy (77 patients) were assessed in patients earlier treated for H. pylori. Results: Of the stool antigen tests studied, the monoclonal antibody-based EIA-test showed the highest sensitivity and specificity both in the pre-treatment setting (96.9% and 95.9%) and after therapy (96.9% and 97.8%). The polyclonal stool antigen test and the in-office test had at baseline a sensitivity of 91% and 94%, and a specificity of 96% and 89%, respectively and in a post-treatment setting, a sensitivity of 78% and 91%, and a specificity of 97%, respectively. Duodenal gastric metaplasia was strongly associated with H. pylori positive duodenal ulcer (odds ratio 42). Although common still five years after eradication, persistent chronic gastric inflammation (21%) and elevated H. pylori antibodies (33%) were neither associated with each other nor with atrophic gastritis. Conclusions: Current H. pylori infection can feasibly be diagnosed by a monoclonal antibody-based EIA test with the accuracy comparable to that of reference methods. The performance of the polyclonal test as compared to the monoclonal test was inferior especially in the post-treatment setting. The in-office test had a low specificity for primary diagnosis and hence positive test results should probably be confirmed with another test before eradication therapy is prescribed. The presence of widespread duodenal gastric metaplasia showed promising results in detecting patients who should be treated for H. pylori due to an increased risk of duodenal ulcer. If serology is used later on in patients with earlier successfully treated for H. pylori, it should be taken into account that H. pylori antibodies may persist elevated for years for unknown reason. However, this phenomenon was not found to be associated with persistent chronic inflammation or atrophic changes.

Oxidation of alkaline earth sulfides to sulfates: Thermodynamic aspects

The emf of the galvanic cell, Pt, Ni + NiO/(CaO) ZrO2/MS + MSO4, Ir, Pt, where M is calcium, strontium, or barium, has been measured in the temperature range 850 to 1100 K. From these measurements the Gibbs’ energy changes for the oxidation of sulfides of alkaline earth metals to their respective sulfates have been calculated. The results are compared with available thermodynamic data in the literature. The agreement varies from ±2 kJ for the strontium system to ±20 kJ in the case of barium. Trends in the stabilities of alkaline earth sulfates are discussed in relation to the properties of the cationic species involved.

Insect induced bud fall in cultivated hibiscus and aspects of the biology of Macroura concolor (Macleay) (Coleoptera: Nitidulidae)

The influence of insect attack on bud fall and subsequent poor flowering in cultivated hibiscus (Hibiscus rosa-sinensis) was studied in cages and in the field in southern Queensland. Three species of Hemiptera (most importantly Aulacosternum nigrorubrum but also Nezara viridula and Tectocoris diophthalmus) caused some bud fall in 2 plantations studied. Adults of Macroura concolor suppressed flowering for long periods in spring and summer. Data from white funnel traps and counts in flowers showed that M. concolor was most active in these seasons. Methiocarb (0.75 g a.i./litre) reduced beetle numbers and increased flowering. When 15 or more adults of M. concolor occurred per bud (or flower) most buds fell and few flowers were produced, but when beetles declined to 10 or fewer many buds survived and widespread flowering occurred. Larvae fed in fallen buds and flowers and the mean duration of development of the combined immature stages was 14 days at 26 deg C. The preference of adults of M. concolor for pale coloured flowers was examined. Hibiscus plants produced most buds from December to June with lower numbers in winter and spring (July to November). Bud production in spring and early summer (September-December) varied greatly and probably contributed to poor flowering, however, even when large numbers of buds occurred very few flowers were produced because of the activities of M. concolor.

Steric Aspects Of The Oxidation Of Thioketones By Singlet Oxygen

Singlet oxygen oxidation of dialkyl thioketones yields the corresponding ketones and in some cases sulfoxides in varying amounts. Steric considerations on the reactive zwitterionic/diradical intermediates have been invoked to rationalise the product distribution.

Mechanistic studies on the action of ammonium phosphate on polymer fire retardancy

The mechanism of fire retardant action of mono- and diammonium phosphates on polystyrene has been investigated. Ignition delay and mass burning rate studies reveal that the phosphates bring down both parameters considerably though to different extents. This has been adequately explained on the basis of the existing combustion models and physicochemical behavior of the material. Similar to their action on cellulosic materials, phosphates bring about fire retardancy in polystyrene via char formation. This is suggested to occur through a series of processes consisting of initial peroxide formation, decomposition to alcohols and aldehydes, formation of alkyl-phosphate esters, dehydration and subsequent char formation. Infrared and mass spectral studies support this mechanism.