Does the Prevalence of Periodontal Pathogens Change in Elderly Edentulous Patients after Complete Denture Treatment?

PURPOSE: To determine if wearing complete dentures can cause changes in prevalence of some of the most common periodontal pathogens in elderly edentulous patients. The need for understanding the composition of oral microflora in edentulous patients has been recognized by some authors, but no studies have dealt with the changes that occur in periodontal pathogens' prevalence as a result of complete dentures. MATERIALS AND METHODS: A total of 30 edentulous elderly (average age 71) patients participated in the study. Complete dentures were fabricated for each patient, and the residual alveolar ridges were swabbed before denture insertion. After a period of 6 months swabs were taken again. Identification of P. intermedia, A. actinomycetemcomitans, P. gingivalis, T. forsythia, T. denticola, and F. nucleatum was done by the polymerase chain reaction (PCR) method and primers specific for each microorganism. RESULTS: A noticeable increase in the presence of periodontal pathogens was observed after 6 months of denture wearing; targeted bacteria were identified in 17 pre-insertion samples compared to 28 post-insertion samples. The McNemar test was used to compare the prevalence of periodontal pathogenic bacteria before and after dental treatment. p<0.05 indicated statistical significance. Three microorganisms showed a statistically significant difference between the first and second swabbing-A. actinomycetemcomitans (6.7% vs. 40.0%, p = 0.006), P. intermedia (30.0% vs. 73.3%, p = 0.004), and T. forsythia (6.7% vs. 30.0%, p = 0.004). There was also an increase in bacteria co-associations 6 months post-insertion of complete dentures. CONCLUSIONS: The results of the present study suggested that wearing complete dentures caused a considerable increase of periodontopathic bacteria prevalence in elderly patients. Better understanding of oral microflora and the impact dental treatment has on bacterial colonies is important in modern dentistry.

Optimization of ultrasound-assisted extraction of phenols from seeds of grape pomace.

The aim of this research was to optimize the extraction condition of ultrasound-assisted extraction (UAE) of phenols from the red grape of Vranac variety (Vitis vinifera L.) pomace seeds. The minimum experiments needed for optimization of UAE by response surface methodology (RSM) were obtained by spectrophotometric and HPLC analyses of seed extracts. UAE greatly depends on three independent variables: extraction temperature, time and liquid/solid ratio. The RSM can be used for optimization of UAE conditions to obtain maximum responses such as extraction yield, TPC, (+)-catechin, (-)-epicatechin and proanthocyanidin content. The predicted values of the model were in accordance with experimental data under the same conditions (RSD was 0.74%). Experimental data also confirmed that UAE gives a better yield of phenolics than conventional solvent extraction (23.76% increase). The UAE under optimal extraction conditions is suitable for obtaining extracts that are rich in phenolic content, and have strong antioxidant activity which could be used as additives in food and medicaments.

Absence of linkage disequilibria between chromosomal arrangements and mtDNA haplotypes in natural populations of Drosophila subobscura from the Balkan Peninsula.

The genetic structure of Drosophila subobscura from the Balkan Peninsula was studied with respect to restriction site polymorphism of mitochondrial DNA in populations from the Derventa River Gorge and Sicevo Gorge (Serbia). To investigate the role of cytonuclear interactions in shaping mitochondrial DNA variability in natural populations of this species, the study was complemented with the analysis of linkage disequilibria between mitochondrial haplotypes and chromosomal inversion arrangements. Similar to other populations of D. subobscura, two main haplotypes (I and II) were found, as well as a series of less common ones. The frequencies of haplotypes I and II accounted for 25.8% and 71.0%, respectively, in the population from the Derventa River Gorge, and for 32.4% and 58.1%, respectively, in the population from Sicevo Gorge. One of the haplotypes harbored a large insertion (2.7 kb) in the A+T rich region. The frequency distribution of both haplotypes did not depart from neutrality. Contrary to prior studies, we did not detect any significant linkage disequilibrium between the two most frequent mtDNA haplotypes and any of the chromosomal arrangements in either of the populations. We conclude that linkage disequilibrium is not a general occurrence in natural populations of D. subobscura, and we discuss how transient coadaptations, ecologically specific selective pressures, and demographics could contribute to population-specific patterns of linkage disequilibrium.

Heterozygosity maintains developmental stability of sternopleural bristles in Drosophila subobscura interpopulation hybrids.

Interpopulation hybridization can lead to outbreeding depression within affected populations due to breakdown of coadapted gene complexes or heterosis in hybrid populations. One of the principal methods commonly used to estimate the level of developmental instability (DI) is fluctuating asymmetry (FA). We used three genetically differentiated Drosophila subobscura populations according to inversion polymorphism analysis and measured the variability of sternopleural bristle number and change in FA across generations P, F1, and F2 between intra- and interpopulation hybrids of D. subobscura. The mean variability of sternopleural bristle number in intra- and interpopulation hybrids of D. subobscura across generations cannot determine whether the changes at the level of developmental homeostasis are due exclusively to genomic coadaptation or to heterozygosity. Phenotypic variance (V(p)) and FA of sternopleural bristle number was higher in interpopulation than in intrapopulation hybrids across generations. F1 hybrids were more developmentally stable compared to each parental population in both intra- and interpopulation hybrids. The most probable mechanism providing developmental homeostasis is heterozygote or hybrid superiority, also called overdominace. However, V(p) was higher and FA lower in the F2 generation when compared to F1, due mainly to crossing-over in the formation of F2.

The effect of royal sun agaricus, Agaricus brasiliensis S. Wasser et al., extract on methyl methanesulfonate caused genotoxicity in Drosophila melanogaster.

The effect of culinary-medicinal Royal Sun Agaricus (Agaricus brasiliensis) hot water extract on methyl methane sulfonate (MMS) induced mutagenicity/genotoxity in Drosophila melanogaster was studied using a quick and broadly applicable in vivo assay, i.e., the wing somatic mutation and recombination test. We used 2nd instar larvae, trans-heterozygous for the third chromosome recessive markers, i.e., multiple wing hairs (mvh) and flare-3 [flr (3)], and fed them for 24 h with the aqueous extract of A. brasiliensis. For antigenotoxicity studies a 24-h pretreatment with the extract was done, followed by a 48-h treatment of the then 3rd instar larvae with MMS. The frequency of mutations of the wing blade changes (i.e., of the number of wing spots of different sizes) induced in somatic cells was determined as a parameter of genetic changes of the wing imaginal discs. The results showed that A. brasiliensis extract did not cause any genotoxic or mutagenic effects. No antigenotoxic and/or protective effect against the induction of mutations by MMS was observed. Instead, a possible enhanced mitotic recombination frequency by MMS was seen after pretreatment of the larvae with A. brasiliensis extract. Possible mechanisms of action are discussed.

An unknown collection of lizards from Afghanistan.

Afghanistan is a herpetologically understudied country with few published papers since the end of "Afghanistan's Golden Age" from the 1930s to the 1970s. Although a detailed checklist of the herpetofauna of the country, based on exploration of herpetodiversity using biodiversity archives, has been published recently, there still exist additional historical data that have not been considered. This is the case for a so far unknown collection of lizards from Afghanistan deposited in the herpetological collection of the Institute for Biological Research "Sinisa Stankovic at the University of Belgrade, Belgrade, Serbia. The material comes from field research conducted in 1972 and contains 27 specimens in seven lizard genera representing four families (Agamidae, Gekkonidae, Lacertidae, Scincidae). This historical collection was examined and basic morphometric data, field data, and photographs are provided, comparing the distributional data with published datasets. Updated species distribution maps reveal new locality or province records and an important range extension for Eurylepis taeniolata Blyth, 1854 which represents the northernmost record for this species in Afghanistan. In addition, one further distribution record for the Bufotes viridis (Laurenti, 1768) complex from the same research trip is noted.

Effect of microhabitat variability on body size in Drosophila subobscura.

We assessed the variation in thorax size, wing size and wing loading in populations of Drosophila subobscura from two ecologically different habitats and within each habitat sampled during three periods of the day. The traits analyzed differed between laboratory reared samples and field collected samples. Differences were mainly caused by environmental factors and genotype x environmental interactions. While there were no significant differences between populations for particular periods of the day, within-population analysis for each sex showed specific differences. Results showed that wing loading was the least variable character in natural populations, also showing the lowest level of sexual dimorphism. The data are discussed from the aspect of the variability of gene arrangement frequencies over daytime periods obtained previously for the same samples. They are consistent with models of maintenance of genetic variability in multi-niche habitats, and are in favour of a type of reactive behaviour dependent on ecological niche qualities on a daily rhythm scale in D. subobscura.

Mating behavior as an indicator of quality of Drosophila subobscura males?

According to current theoretical predictions, any deleterious mutations that reduce nonsexual fitness may have a negative influence on mating success. This means that sexual selection may remove deleterious mutations from the populations. Males of good genetic quality should be more successful in mating, compared to the males of lower genetic quality. As mating success is a condition dependent trait, large fractions of the genome may be a target of sexual selection and many behavioral traits are likely to be condition dependent. We manipulated the genetic quality of Drosophila subobscura males by inducing mutations with ionizing radiation and observed the effects of the obtained heterozygous mutations on male mating behavior: courtship occurrence, courtship latency, mating occurrence, latency to mating and duration of mating. We found possible effects of mutations. Females mated more frequently with male progeny of nonirradiated males and that these males courted females faster compared to the male progeny of irradiated males. Our findings indicate a possible important role of sexual selection in purging deleterious mutations.

Evaluation of genotoxic effects of Apitol (cymiazole hydrochloride) in vitro by measurement of sister chromatid exchange.

Apitol, with cymiazole hydrochloride as the active ingredient, is used in bee-keeping against the ectoparasitic mite Varroa destructor. The preparation was evaluated for genotoxicity in cultured human peripheral blood lymphocytes. Sister chromatid exchange, the mitotic index and the cell proliferation index were determined for three experimental concentrations of Apitol (0.001, 0.01 and 0.1 mg/ml). All concentrations significantly (p < 0.001) increased the mitotic index (MI = 7.35+/-0.18%, 8.31+/-0.20% and 12.33+/-0.25%, respectively), the proliferative index (PI = 1.83+/-0.01, 1.84+/-0.01 and 1.88+/-0.02, respectively) and the frequency of sister chromatid exchange (SCE = 8.19+/-1.81, 8.78+/-1.80 and 13.46+/-1.88, respectively), suggesting that cymiazole hydrochloride has genotoxic potential.

Drosophila subobscura flies adapted to low lead concentration carry no fitness cost.

As a response to the long-term presence of heavy metals in the environment, populations can evolve resistance. Its maintenance may have detrimental effect on population's fitness, causing a fitness cost. Lead is one of the widely distributed elements in the environment exhibiting high toxicity on organisms. By analyzing developmental stages viability and developmental time, we evaluated fitness cost in Drosophila subobscura flies adapted to low lead concentration and control flies derived from the same wild population, as well as their hybrids. Significant changes in specific developmental stages viability were detected in both lines, as well as their hybrids, suggesting complex response to low lead concentration. The results show that a long-term exposure to low lead concentration may have a significant impact on a population's survival, especially in a changing environment conditions.

The behavior of fixed and switching oxide traps of RADFETs during irradiation up to high absorbed doses.

The behavior of radiation-induced fixed traps (FTs) in gate oxide and radiation-induced switching traps (STs) near and at the gate oxide/substrate interface during irradiation up to high absorbed doses has been considered. The zero-bias voltage regime, the simplest and most popular solution in practice, was chosen. Indeed, it is very difficult to predict the creation of radiation defects in the case of low electric fields, because there is a compromise between the external low electric fields induced by work function differences and the internal electrical fields induced by radiation-induced charged defects in the oxide. It was shown that the density of FTs is higher than the density of STs for lower absorbed doses, though the trend is reversed for doses greater than 700Gy. Although the number of FTs is much higher than the number of STs, many FTs are located in the bulk, far from the oxide/semiconductor interface and their influence on channel carriers is much smaller than the influence of STs that are located closer to the channel. The equation for fitting the threshold voltage components induced by FTs (ΔVft) and by STs (ΔVst) is proposed and very good fittings are obtained. It is shown that five experimental irradiation points are sufficient to draw a good conclusion about the values of the fitting parameters, i.e., the voltage saturation values and the degree of linearity.

Effect of lead pollution on fitness and its dependence on heterozygosity in Drosophila subobscura.

Lead is one of the most present contaminants in the environment, and different species respond differently to this type of polution. If combined with genomic stress, lead may act synergistically, causing significant decrease of fitness components. We used two genetically diverse Drosophila subobscura populations (regarding both putatively adaptive inversion and microsatellite loci polymorphisms) originating from two ecologically distinct habitats. To establish different levels of genome heterozygosity, series of intraline, intrapopulation and interpopulation crosses were made. The progeny were reared on a standard medium and a medium with 200 µg/mL of lead acetate. Development time was significantly extended to all groups reared on lead. The progeny of intraline crosses showed significantly extended development time compared to all other groups. The obtained results suggest that genome heterozygosity reduces the effect of lead pollution.

Treatment of obstructive sleep apnea patients using oral appliances--our experiences.

BACKGROUND/AIM: Obstructive sleep apnea (OSA) is one of the most prevalent sleep disorders. It is recognized as a serious risk factor for car and workplace accidents due to daytime sleepiness, and factor for coronary heart diseases and stroke. The aim of this study was to examine the effectiveness of oral appliances for mandibular advance in treating mild to moderate OSA. METHODS: A total of 15 patients were included in this study, all diagnosed with mild or moderate OSA. Oral appliances were custom made for each patient in protrusive position at 50% of maximum mandibular advancement. The patients were given instructions not to sleep on their backs and avoid alcohol consumption during the study as these are the factors that can contribute to symptoms progression. RESULTS: Complete and partial treatment success was achieve in 14 of the patients. Apnea-hypopnea index values were significantly lower (p < 0.05) at the end of a 6-month observation period compared to those at the treatment beginning. A great improvement in symptoms was observed, with daytime sleepiness index values significantly reduced already within the first month of the treatment. CONCLUSION: Treatment of obstructive sleep apnea with oral appliances has proven successful. Patients were comfortable using oral appliances and were ready to wear them for prolonged period of time. Use of oral appliances is very common in the world and should not be discarded. They are also very comfortable, practical and affordable comparing to continuous positive airway pressure (CPAP) apparatus, not to mention surgery. Use of oral appliances is safe and very well tolerated, and ought to be offered to patients with OSA.

Human external ophthalmomyiasis caused by Lucilia sericata Meigen (Diptera: Calliphoridae)--a green bottle fly.

Ophthalmomyiasis externa is the result of infestation of the conjunctiva by the larval form or maggots of flies from the order Diptera. If not recognized and managed appropriately, it can be complicated by the potentially fatal condition ophthalmomyiasis interna. Ophthalmomyiasis externa is mainly caused by the sheep bot fly (Oestrus ovis). We present the first case, to our knowledge, of ophthalmomyiasis externa in an elderly woman from Belgrade caused by Lucilia sericata Meigen--a green bottle fly.

[Heritability of bipolar affective disorder--family study].

BACKGROUND/AIM: Bipolar affective disorder is mental disorder with polygenic type of heredity. Heritability--relation between genetic and environmental variance is used to estimate the level of influence of genetic variance to phenotype variance. Study results show decreasing trend in the value of heritability of bipolar affective disorder, thus indicating that this disorder is a complex behavioral threshold characteristic. Therefore, the aim of this study was to estimate the contribution of genetic variance to phenotype variance of bipolar affective disorder, i.e. to estimate heritability of this disorder. METHODS: By the use of a questionnaire, 80 patients with over crossed threshold for bipolar affective disorder were asked for functional information about the members of their families belonging to the first degree of relation (fathers, mothers and full-sibs). By using "Applet for calculating heritability for threshold traits (disease)", and regression analysis, heritability of bipolar affective disorder as well as its statistical significance, were estimated (chi2 test). RESULTS: Heritability and relationship of genetic and environmental variance of bipolar affective disorder is 0.2 with statistically significant difference from zero (p < 0.001). CONCLUSION: The estimated contribution of genetic variance to phenotype variance of bipolar affective disorder is low being 20%, while the contribution of environmental variance is 80%. This result contributes to the understanding of bipolar affective disorder as a complex behavioral threshold trait.

Antimutagenic effect of sage tea in the wing spot test of Drosophila melanogaster.

The present study assayed the antimutagenic potential of Salvia officinalis (sage) in the form of tea infusion, by the somatic mutation and recombination test (SMART) on Drosophila melanogaster. The use of herbal infusions is much common in the human diet, so the aim of the present study was to estimate the antimutagenic effects of the S. officinalis tea rather than essential oils. Methyl methanesulphonate (MMS) was used as the mutagen and positive control. Several types of treatment were performed: short acute treatment with sage infusion or MMS, longer (chronic) treatment with sage solution or MMS, and two combined treatments, i.e. short treatment with sage followed by a longer treatment with MMS and vice versa. Sage infusion used in our experiments showed a clear antimutagenic effect, reducing the frequency of mutations induced by MMS. The inhibition effect of sage tea is obtained and confirmed when pre- or post-treatments with mutagen were used. The results indicate that although sage in this regime decreases the number of mutation events, it is not efficient enough in case of the 2 h sage pre-treatment. Antioxidant activity, suppression of metabolic activation, could be mechanisms through which sage or some of its components act as desmutagen.

Monitoring of the genetic structure of natural populations: change of the effective population size and inversion polymorphism in Drosophila subobscura.

We analyzed changes in the genetic structure and effective population size of two ecologically distinct populations of Drosophila subobscura over several years. Population sizes of D. subobscura in beech and oak wood habitats for a period of 6 years were estimated by the capture-mark-release-recapture method. Inversion polymorphism parameters were also assessed in the same populations for a period of 3 years. Significant differences in the numbers of individuals were observed between sexes. This affected the effective population sizes between particular years. The ratio of the effective size over the cenzus dropped significantly in beech wood in 2 years. Although overall heterozygosity remained unchanged during the years in both habitats, frequencies of gene arrangements on five chromosomes show variability. After the bottleneck, some complex chromosomal arrangements appeared for the first time in both populations. Standard gene arrangements of chromosome A increased in frequency over the years in each habitat, while the complex arrangements remain rather stable and specific for each population. The results obtained indicate that the population structure may significantly change if the effective size of D. subobscura population is reduced, which is mostly related to microclimatic changes in habitats. Based on the results to date, monitoring of microevolutionary changes by using D. subobscura and its relatives seems a promising way to study the effects of global climate changes.