Oral Fluid–Based Biomarkers of Alveolar Bone Loss in Periodontitis

Periodontal disease is a bacteria-induced chronic inflammatory disease affecting the soft and hard supporting structures encompassing the teeth. When left untreated, the ultimate outcome is alveolar bone loss and exfoliation of the involved teeth. Traditional periodontal diagnostic methods include assessment of clinical parameters and radiographs. Though efficient, these conventional techniques are inherently limited in that only a historical perspective, not current appraisal, of disease status can be determined. Advances in the use of oral fluids as possible biological samples for objective measures of current disease state, treatment monitoring, and prognostic indicators have boosted saliva and other oral-based fluids to the forefront of technology. Oral fluids contain locally and systemically derived mediators of periodontal disease, including microbial, host-response, and bone-specific resorptive markers. Although most biomarkers in oral fluids represent inflammatory mediators, several specific collagen degradation and bone turnover-related molecules have emerged as possible measures of periodontal disease activity. Pyridinoline cross-linked carboxyterminal telopeptide (ICTP), for example, has been highly correlated with clinical features of the disease and decreases in response to intervention therapies, and has been shown to possess predictive properties for possible future disease activity. One foreseeable benefit of an oral fluid–based periodontal diagnostic would be identification of highly susceptible individuals prior to overt disease. Timely detection and diagnosis of disease may significantly affect the clinical management of periodontal patients by offering earlier, less invasive, and more cost-effective treatment therapies.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73247/1/annals.1384.028.pd

Menus for Feeding Black Holes

Black holes are the ultimate prisons of the Universe, regions of spacetime where the enormous gravity prohibits matter or even light to escape to infinity. Yet, matter falling toward the black holes may shine spectacularly, generating the strongest source of radiation. These sources provide us with astrophysical laboratories of extreme physical conditions that cannot be realized on Earth. This chapter offers a review of the basic menus for feeding matter onto black holes and discusses their observational implications.Comment: 27 pages. Accepted for publication in Space Science Reviews. Also to appear in hard cover in the Space Sciences Series of ISSI "The Physics of Accretion onto Black Holes" (Springer Publisher

The Effects of Sugars Intake and Frequency of Ingestion on Dental Caries Increment in a Three-year Longitudinal Study

A three-year longitudinal study was carried out with a group of children, initially aged 11-15, residing in non-fluoridated rural communities in south-central Michigan. This report analyzes the relation between caries increment and consumption of sugars from all sources to see if accepted relationships have changed with the caries decline in the United States. There were 499 children who provided three or more 24-hour dietary recall interviews, and who received dental examinations at baseline and after three years. Caries increment averaged 2.91 DMFS over the three years, with 81 % of new lesions on pit-and-fissure surfaces. Consumption of sugars from all sources averaged 156 g per day for males and 127 g per day for females, an average of 52 kg per person per year. Sugars constituted one-quarter of total caloric intake for both boys and girls, and the average number of eating occasions per day was 4.3. Children who consumed a higher proportion of their total energy intake as sugars had a higher increment of approximal caries, though there was little relation to pit-and-fissure caries. The average number of daily eating occasions was not related to caries increment, nor was the average number of sugary snacks (defined as foods with 15% or more of sugars) consumed between meals, but the average consumption of between-meal sugars was related to the approximal caries increment. When children were categorized by high caries increment compared with no caries increment, a tendency toward more frequent snacks was seen in the high-caries children. In an age of generally declining caries, it was concluded that higher average daily consumption of sugars, and higher between-meal consumption of sugars, was still a risk factor for children susceptible to approximal caries. Overall frequency of eating and frequency of ingestion of sugary foods between meals, however, were both poorly related to approximal caries increment. Pit-and-fissure caries could not be related to any aspect of sugars consumption.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67206/2/10.1177_00220345880670111201.pd

THE RATE OF BINARY BLACK HOLE MERGERS INFERRED FROM ADVANCED LIGO OBSERVATIONS SURROUNDING GW150914

A transient gravitational-wave signal, GW150914, was identi fi ed in the twin Advanced LIGO detectors on 2015 September 2015 at 09:50:45 UTC. To asse ss the implications of this discovery, the detectors remained in operation with unchanged con fi gurations over a period of 39 days around the time of t he signal. At the detection statistic threshold corresponding to that observed for GW150914, our search of the 16 days of simultaneous two-detector observational data is estimated to have a false-alarm rate ( FAR ) of < ́ -- 4.9 10 yr 61 , yielding a p -value for GW150914 of < ́ - 210 7 . Parameter estimation follo w-up on this trigger identi fi es its source as a binary black hole ( BBH ) merger with component masses ( )( ) = - + - + mm M ,36,29 12 4 5 4 4 at redshift = - + z 0.09 0.04 0.03 ( median and 90% credible range ) . Here, we report on the constraints these observations place on the rate of BBH coalescences. Considering only GW150914, assuming that all BBHs in the universe have the same masses and spins as this event, imposing a search FAR threshold of 1 per 100 years, and assuming that the BBH merger rate is constant in the comoving frame, we infer a 90% credible range of merger rates between – -- 2 53 Gpc yr 31 ( comoving frame ) . Incorporating all search triggers that pass a much lower threshold while accounting for the uncerta inty in the astrophysical origin of each trigger, we estimate a higher rate, ranging from – -- 13 600 Gpc yr 31 depending on assumptions about the BBH mass distribution. All together, our various rate estimat es fall in the conservative range – -- 2 600 Gpc yr 31

Método para avaliação clínica da capacidade tamponante salivar A method for the clinical evaluation of salivary buffer capacity

O presente estudo teve por objetivo o desenvolvimento e a padronização de um método colorimétrico para avaliar a capacidade tamponante salivar média de nossa população. As amostras de saliva estimulada foram tituladas sem eliminação do CO2. Estudos foram realizados para verificar a influência da perda de CO2 das amostras durante o período necessário para a realização das titulações e para a padronização do tempo de leitura do pH. A partir das titulações realizadas nas amostras de saliva de 206 indivíduos de ambos os sexos na faixa etária de 5 a 50 anos, na proporção de 0,77:1:0,44, respectivamente para crianças, jovens e adultos, foram feitas as distribuições de freqüências dos casos, a determinação média do pH inicial, do pKa, microequivalentes relativos ao final da titulação, pH final da titulação e uma estimativa da porcentagem da saliva titulada em pH 5. Com base nestas variáveis foi estabelecida uma classificação dos indivíduos quanto à capacidade tamponante. Análise dos resultados utilizando-se 11, 12 ou 13 microequivalentes de H+/ml indicam que o valor de 11 microequivalentes/ml de saliva é o mais apropriado para a avaliação da capacidade tamponante salivar em nossa população.<br>The present study aimed to develop and standardize a colorimetric method for assessing salivary buffer capacity adapted to the features of the Brazilian population. Samples of stimulated saliva were titrated without CO2 elimination. The assessment was carried out to study the influence of the loss of CO2 from the samples during the few minutes necessary for titration, and to standardize the instants for measuring pH. Saliva samples were titrated from 206 individuals from both genders, between 5 and 50 years of age, and in a proportion of 0.77 : 1 : 0.44, respectively of children, youngsters, and adults. Case frequency distribution; determination of average values of initial pH, pKa, µ equivalents related to titration end point and final pH; and estimate of the percentage of saliva titrated at a pH of 5.0 were calculated based on the data collected. The results were used to classify individuals according to their salivary buffer capacity by colorimetric pH determinations using 11,12, and 13 µ equivalents of H+/ml saliva, and were compared to case frequency distribution obtained from saliva titration data. The results indicate that 11 µ equivalents H+/ml of saliva is the most appropriate for clinically evaluating the salivary buffer capacity of our population