Time series forecasting methods in emergency contexts.

The key issues in any fire emergency are recognising fire hotspots, locating the emergency intervention team (EI), following the evolution of the fire, and selecting the evacuation path. This leads to the study and development of HelpResponder, a solution capable of detecting the focus of interest in hostile spaces derived from fire due to high temperatures without visibility. A study is conducted to determine which model best predicts measured [Formula: see text] levels. The variables used are temperature, humidity, and air quality, obtained from sensors installed in a fire tower. The statistical methods applied, namely ARIMAX, KNN, SVM, and TBATS, allow the adjustment and modelling of the variables. Explanatory variables with temporal structure are incorporated into SVM, a new improvement proposal. Moreover, combining different models showed the best efficiency in forecasting. In fact, another contribution of our work lies in offering a small-scale prediction system that is specifically designed to save batteries. The system has been tested and validated in a hostile environment (building), simulating real emergency situations. The system has been tested and validated in several hostile environments, simulating real emergency situations. It can help firefighters respond faster in an emergency. This reduces the risks associated with the lack of information and improves the time for tactical operations, which could save lives.

Green Synthesis for Carbon Quantum Dots via Opuntia ficus-indica and Agave maximiliana: Surface-Enhanced Raman Scattering Sensing Applications.

In this study, we present an alternative method for synthesizing carbon quantum dots (CQDs) using a green synthesis approach via extracts from Agave maximiliana and Opuntia ficus-indica(Ofi). The extracts from both plants were used as the carbon source for the CQDs. The synthesis method employs mesoporous zeolite 4A as a refractory for the thermal treatment of the samples. Transmission electron microscopy analysis established that the size of the CQDs shows a narrow distribution centered around 2 nm with a maximum size of less than 3 nm for both cases. The CQDs exhibit absorption bands associated with π-π* transitions located around 220 nm. In both cases, photoluminescence (PL) phenomenon was detected by irradiating the samples with a UV wavelength and detecting emissions close to the blue wavelength. Additionally, both kinds of CQDs were tested as surface-enhanced Raman scattering (SERS) substrates against methylene blue (MB), indicating an enhancement associated with ring deformation and stretching modes of the v(C-C) and v(C-N) bonds located around 1400 and 1620 cm-1, respectively. Complementarily, in the framework of density functional theory, H2nC2(2m+1) structures (with n = 3-5 and m = 1-3) were used as a theoretical representation of CQDs in interaction with the MB molecule. It is used for developing the analysis of charge transfer effects between both systems and for specifying elements that generate the SERS effect associated with the chemical enhancement mechanism.

Contribution of Singular Spectral Analysis to Forecasting and Anomalies Detection of Indoors Air Quality.

The high impact of air quality on environmental and human health justifies the increasing research activity regarding its measurement, modelling, forecasting and anomaly detection. Raw data offered by sensors usually makes the mentioned time series disciplines difficult. This is why the application of techniques to improve time series processing is a challenge. In this work, Singular Spectral Analysis (SSA) is applied to air quality analysis from real recorded data as part of the Help Responder research project. Authors evaluate the benefits of working with SSA processed data instead of raw data for modelling and estimation of the resulting time series. However, what is more relevant is the proposal to detect indoor air quality anomalies based on the analysis of the time derivative SSA signal when the time derivative of the noisy original data is useless. A dual methodology, evaluating level and dynamics of the SSA signal variation, contributes to identifying risk situations derived from air quality degradation.

Electrohydrodynamic Processing of PVP-Doped Kraft Lignin Micro- and Nano-Structures and Application of Electrospun Nanofiber Templates to Produce Oleogels.

The present work focuses on the development of lignin micro- and nano-structures obtained by means of electrohydrodynamic techniques aimed to be potentially applicable as thickening or structuring agents in vegetable oils. The micro- and nano-structures used were mainly composed of eucalyptus kraft lignin (EKL), which were doped to some extent with polyvinylpyrrolidone (PVP). EKL/PVP solutions were prepared at different concentrations (10-40 wt.%) and EKL:PVP ratios (95:5-100:0) in N, N-dimethylformamide (DMF) and further physico-chemically and rheologically characterized. Electrosprayed micro-sized particles were obtained from solutions with low EKL/PVP concentrations (10 and 20 wt.%) and/or high EKL:PVP ratios, whereas beaded nanofiber mats were produced by increasing the solution concentration and/or decreasing EKL:PVP ratio, as a consequence of improved extensional viscoelastic properties. EKL/PVP electrospun nanofibers were able to form oleogels by simply dispersing them into castor oil at nanofiber concentrations higher than 15 wt.%. The rheological properties of these oleogels were assessed by means of small-amplitude oscillatory shear (SAOS) and viscous flow tests. The values of SAOS functions and viscosity depended on both the nanofiber concentration and the morphology of nanofiber templates and resemble those exhibited by commercial lubricating greases made from traditional metallic soaps and mineral oils.

Radon alpha track counting on solid state nuclear track detector by an ImageJ-based software macro.

Radon (222Rn) is a radioactive gas emanating from geological materials. Inhalation of this gas is closely related to an increase in the probability of lung cancer if the levels are high. The usual methodology for the quantification of radon by passive methods is the use of etched solid-state nuclear track detectors, frequently in combination with optical microscopes or image scanning for image acquisition and software-based image processing for track counting. Currently available commercial instrumentation, as the Radosys microscopy system, is quite expensive, so the development of alternative methodologies is desirable. In this work, a simple, fast and low-cost image acquisition system for the determination of tracks in chemically etched CR-39 solid-state nuclear track detectors to quantify 222Rn alpha tracks has been proposed. The image of the detector surface is obtained by a conventional light stereoscopic microscope, transmitted by a CCD camera into the computer, and analyzed by the ImageJ open-source software. This methodology was employed to analyze 45 samples collected in dwellings and caves located in the region of Extremadura (Southwest Spain). Results show a good correlation coefficient of r2 = 0.98 between the reference and purposed methodology and excellent repeatability, demonstrating that the system enables routine counting tracks for radon measurement as an alternative to the Radosys microscopy instrument.

Evaluation of undergraduate Endodontic teaching in dental schools within Spain.

AIM: To evaluate the current situation of undergraduate endodontic teaching in Spanish dental schools. METHODOLOGY: An online version, translated into Spanish, of a survey conducted in the UK (Int Endod J 52, 2019, 1077) was sent via email to the undergraduate endodontic programme leads in all 23 Spanish dental schools. RESULTS: The response rate was 96%. In 95% of dental schools, endodontics is taught in the fourth year. Students treat simple root canal treatment cases in 100% of schools and only in 40% treat moderate cases. In 65% of schools, students are supervised by full-time professors who are specialists in Endodontics, significantly more frequently in private dental schools (P = 0.002). Spanish dental schools use both rotary and reciprocating instrumentation systems during endodontic training, with consistency on methods of working length determination, use of silicate-based endodontic cements, irrigating solutions, inter-visit medicaments and canal filling techniques. No type of magnification is used in 90% of dental schools, and only 25% use ultrasonic instruments. Private dental schools have a significantly better staff: student ratio during clinical practice (P = 0.041), spend significantly more hours in clinical training (P = 0.04) and have significantly greater number of clinical areas specifically dedicated to Endodontics (P = 0.010). CONCLUSIONS: Undergraduate endodontic teaching in Spanish dental schools follows the key recommendations of the ESE Undergraduate Curriculum Guidelines (Int Endod J 46, 2013, 1105), being, in most respects, comparable to that carried out in the UK (Int Endod J 52, 2019, 1077). The use of magnification and ultrasonic instruments needs to be increased. Private schools reported better results than public schools in some of the variables that were analysed.

Prevalence of endodontic infection in patients with Crohn´s disease and ulcerative colitis.

BACKGROUND: Previous studies have linked apical periodontitis (AP) to inflammatory bowel disease (IBD). The aim of this study was to compare the prevalence of AP and root canal treatment (RCT) in patients with ulcerative colitis (UC) and Crohn´s disease (CD). MATERIAL AND METHODS: A cross-sectional study, including 28 patients with Crohn´s disease and 26 with ulcerative colitis, was conducted. AP was diagnosed as radiolucent periapical lesions (RPLs), using the periapical index score (PAI). Student's t test, 2 test and multivariate logistic regression were used in the statistical analysis. RESULTS: Multivariate logistic regression run with age, gender, number of teeth, number of RFT, periodontal disease and the type of IBD as covariates, taking as dependent variable and outcome "periapical status" (0 = no tooth with RPL; 1 = at least one tooth with RPL), showed that both UC and CD patients had the prevalence apical periodontitis (OR = 1.03; C.I. 95% = 0.25 - 4.31; p = 0.97). The multivariate analysis, including all the above covariates, shows that both in UC and CD patients the prevalence of RCT was similar (OR = 0.76; C.I. 95% = 0.17 - 7.31; p = 0.73). Periapical status was significantly associated with endodontic status (OR = 42.72; C.I. 95% = 3.87 - 472.15; p = 0.002), regardless of IBD type. CONCLUSIONS: The results of the present study show similar frequency of AP and RFT in both UC and CD patients. The type of IBD does not appear to affect the prevalence of radiographically detectable periapical lesions or the prevalence of root canal treatment.

Cribado neonatal de drepanocitosis en Castilla y León: Estudio descriptivo / Neonatal screening of drepanocytosis in Castilla y Leon (Spain): a descriptive study

Introducción. La anemia falciforme es una enfermedad de herencia autosómica recesiva que constituye una de las alteraciones genéticas más frecuentes del noroeste de Europa. Las complicaciones secundarias en los pacientes homocigotos son frecuentes durante los primeros 3 años de vida, y debido a ello, desde el 12 de julio de 2017, se ha incluido dicha patología dentro de las enfermedades objetivo de cribado neonatal de Castilla y León (CyL). Con tal fin, se pretende detectar aquellos pacientes que se beneficiarán de un diagnóstico y tratamiento precoz. Objetivos. Calcular la incidencia de hemoglobinopatía S, C, D, E u otra cadena de hemoglobina anómala en todo recién nacido vivo en CyL desde el inicio del programa de cribado hasta el 12 deoctubre de 2018 (15 meses), determinando en los distintos pacientes el sexo, lugar de origen del padre y la madre, hospital de nacimiento y fenotipo encontrado. Material y métodos. Estudio retrospectivo y descriptivo de los pacientes con cribado neonatal de hemoglobinopatías patológico nacidos en la Comunidad Autónoma de Castilla y León, del 12 de julio de 2017 al 12 de octubre de 2018. La muestra de sangre se obtuvo de la prueba del talón realizada en las maternidades de forma sistemática, a partir de las 48 horas de vida del niño. Se analizó por cromatografía líquida de alta resolución (Bio-Rad VARIANTnbs System) en Laboratorio de Referencia de Valladolid, detectándose fenotipos S, C, D, E o asociados a cualquier otra cadena de hemoglobina anómala sin tipificar. Resultados. Se incluyeron en el estudio 18.998 recién nacidos durante ese periodo, con un total de 18.975 muestras analizadas (99,8%). Se detectaron un total de 94 muestras positivas, con 1 resultado coincidente con fenotipo FS (1/18.975), 61 para fenotipo FAS (1/311), 14 FAC (1/1.355), 2 FAD (1/9.487), 1 FC (1/18.975), 11 FAX (1/1.725), y 4 FAXX (1/4.743) (AU)

Introduction. Sickle cell disease is an autosomal recessive hereditary disease that constitutes one of the most frequent genetic alterations in the Northeast of Europe. The second ary complications in the homozygous patients are frequent during the first three years of life, and due to it, this condition has been included within the diseases targeted for neonatal screening of Castilla y Leon (CyL) since 12 July 2017. With that in mind, it is aimed to detect those patients who would benefit from and early diagnosis and treatment. Objectives. To calculate the incidence of hemoglobin diseases S, C, D, E or other abnormal hemoglobin chain, in all live newborn in CyL from the onset of the screening program until 12 October 2018 (15 months), determining gender, place of origin of the father and mother, hospital where born and phenotype found in the different patients. Material and methods. A retrospective and descriptive study of the patients with neonatal screening for pathological hemoglobin disease in the Regional Community of Castilla y León, from 17 July 2017 to 12 October 2018. The blood sample was obtained from the heel test conducted in the maternity wards systematically, beginning at 48 hours of life of the child. It was analyzed during rapid resolution liquid chromatography (Bio-Rad VARIANTnbs System) in the Reference laboratory of Valladolid, detecting the S, C, D, E or phenotypes or those associated to any other non-typified abnormal hemoglobin chain. Results. A total of 18,998 newborns were enrolled in the study during this period, with a total of 18,975 samples analyzed (99.8%). A total of 94 positive samples were detected, with 1 result coinciding with FS phenotype (1/18,975), 61 for FAS phenotype (1/311), 14 FAC (1/1,355), 2 FAD (1/9,487), 1 FC (1/18,975), 11 FAX (1/1,725), and 4 FAXX (1/4,743). No screening was conducted in 23 newborns out of all the children, due to death in the first hours or transfer prior to 48 hours of life (AU)

Antimicrobial effect of nanostructured membranes for guided tissue regeneration: an in vitro study.

OBJECTIVE: The purpose of this in vitro study was to evaluate the antibacterial effect of a novel non-resorbable, bioactive polymeric nanostructured membrane (NMs), when doped with zinc, calcium and doxycycline. METHODS: A validated in vitro subgingival biofilm model with six bacterial species (Streptococcus oralis, Actinomyces naeslundii, Veillonela parvula, Fusobacterium nucleatum, Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans) was used. The experimental NMs, with and without being doped with doxycycline, calcium and zinc, were placed on hydroxyapatite (HA) discs. As positive control membranes, commercially available dense polytetrafluoroethylene (d-PTFE) membranes were used and, as negative controls, the HA discs without any membrane. The experimental, positive and negative control discs were exposed to a mixed bacterial suspension, at 37 °C under anaerobic conditions, during 12, 24, 48 and 72 h. The resulting biofilms were analyzed through scanning electron microscopy (SEM), to study their structure, and by quantitative polymerase chain reaction (qPCR), to assess the bacterial load, expressed as colony forming units (CFU) per mL. Differences between experimental and control groups were evaluated with the general linear model and the Bonferroni adjustment. RESULTS: As shown by SEM, all membrane groups, except the NMs with doxycycline, resulted in structured biofilms from 12-72 hours. Similarly, only the membranes loaded with doxycycline demonstrated a significant reduction in bacterial load during biofilm development, when compared with the control groups (p < 0.001). SIGNIFICANCE: Doxycycline-doped nanostructured membranes have an impact on biofilm growth dynamics by significant reducing the bacterial load.

[Analysis of the demand for detection of SARSCoV-2 in a health area of Spain]. / Análisis de la demanda de detección de SARS-CoV-2 en un área de salud de España.

OBJECTIVE: Since the discovery of the SARS-CoV-2 virus, the polymerase chain reaction technique (RT-PCR) has become the fundamental method for diagnosing the disease in its acute phase. The objective is to describe the demand-based series of RT-PCR determinations received at a Microbiology Service at a third-level reference hospital for a health area for three months spanning from the onset of the epidemic by SARS-CoV-2. METHODS: A retrospective analysis of the total of the RT-PCR requested in the Microbiology Service analyzed from 02/25/2020 to 05/26/2020 (90 days) has been carried out. They have been grouped by epidemiological weeks and by the petitioner service. A descriptive analysis was carried out by age, gender and number of requests for each patient. In the tests carried out, a confidence level of 95% (p <0.05) was considered significant. RESULTS: A total of 27,106 requests was received corresponding to 22,037 patients. Median age 53.7 (RIC 40.9-71.7) years, women: 61.3%. Proportion of patients with any positive RT-PCR: 14%. Of the total requests for RT-PCR, positive 3,710. Week 13 had the highest diagnosis performance (39.0%). The primary care has been the service thar has made the most requests (15,953). Patients with 3 or more RT-PCR: 565, of them, 19 patients had a positive result after previously having a negative one. CONCLUSIONS: Requests have been increasing depending on the evolution of the epidemic. The RT-PCR has a high diagnostic performance in the phases of highest contagiousness and / or transmissibility of the virus.

Cardiovascular diseases and apical periodontitis: association not always implies causality.

BACKGROUND: Several studies published in the last two decades have found an association between the prevalence of apical periodontitis (AP) or root canal treatment (RCT) and cardiovascular diseases (CVDs). However, the demonstration of association does not prove by itself the existence of a cause-effect relationship. Two diseases can appear as statistically related without any of them directly affecting the values of the other, resulting in a non-causal relationship. The aim of this narrative review is to summarize the current state of knowledge regarding the association between AP and CVDs, analysing it according to the Hill's causality criteria. MATERIALS AND METHODS: Epidemiological studies carried out on the association between CVDs and AP or RCT published in English until 8 December 2019 were identified. Forty-four articles were selected and its results were analysed. RESULTS: Numerous cross-sectional epidemiological studies have found significant relationship between CVDs and AP. The odds ratio values range 1.6 - 5.4. However, other studies have not found significant association. Respect to RCT, some studies found correlation, but others found no association or even found that RCT is a protective factor against CVDs. CONCLUSIONS: The results are inconsistent and a causal relationship between CVDS and endodontic disease cannot be stablished. The risk factors common to both diseases can act as confounding factors, biasing the results. To reach definitive conclusions about the type of association (causal or non-causal) between both diseases, longitudinal epidemiological studies must be carried out to establish the temporal relationship and the dose-response gradient.

[Prognostic factors on mortality in patients admitted to hospital with heart failure]. / Factores predictores de mortalidad en pacientes hospitalizados por insuficiencia cardíaca.

BACKGROUND: Heart failure (HF) is the leading cause of hospitalization for aging populations in Western countries, and is showing an increasing mortality. The aim of this study was to assess the probable long-term mortality risk factors for patients admitted because of HF. METHODS: Retrospective study of a cohort of 202 patients consecutively hospitalized because of HF and followed up for a maximum period of 5 years. Clinical and epidemiological factors and their relationship to in-hospital and long-term mortality were analyzed. RESULTS: In-hospital mortality was 16%.The independent predictors were: age >75 years (HR?=?2.68, 95%?IC: 1.65-4.36, p?=?0.001); cognitive impairment (HR?=?2.77, 95%?IC: 1.40-5.48, p?=?0.004); Barthel index =60 (HR?=?0.54, 95%?IC: 0.37-0.78, p?=?0,009); creatinine levels >1.16 mg/dl at admission (HR?=?1.57, 95%?IC: 1.12-2.20, p?=?0.009); and number of diagnostics >10 on discharge (HR?=?1. 64, 95%?IC: 1.14-2.36, p?=?0.007). Accumulated mortality at 12, 24, 36 and 48 months after hospital discharge were 43%, 51%, 67% and 70%, respectively; the independent predictors for this were: age >75 years (HR?=?2.55, 95%?IC: 1.56-4.15, p?<0.001); cognitive impairment (HR?=?2.45, 95%?IC: 1.22-4.90, p?=?0.011); creatinine levels >1.16 mg/dl on admission (HR?=?1.59, 95%?IC: 1.12-2.24, p?=?0.009); systolic blood pressure >140 mm Hg on admission (HR?=?0.56, 95%?IC: 0.40-0.80, p?<0.001); and number of diagnostics >10 on discharge (HR?=?1. 49, 95%?IC: 1.03-2.16, p?=?0.033). CONCLUSIONS: Clinical and epidemiological factors related to in-hospital and long-term mortality could help to improve the management of patients with HF.

Association between dental anxiety and intraoperative pain during root canal treatment: a cross-sectional study.

AIM: To investigate whether dental anxiety influences the intraoperative pain felt by patients during root canal treatment. METHODOLOGY: In a cross-sectional design, 180 patients (90 men and 90 women) were included. Pre-operative anxiety levels were assessed using the short-form Dental Anxiety Inventory (S-DAI). Pain during root canal treatment was evaluated using a 10-cm visual analogue scale (VAS) that ranked the level of pain between 'Absence of pain' and 'Unbearable pain'. The minimal sample size was determined using the software of the National Center for Advancing Translational Sciences (NIH, UK). Multivariate logistic regression analysis was used to identify relationships between variables. RESULTS: Mean pain level during root canal treatment was 2.2 ± 2.1. The mean anxiety S-DAI score was 27.2 ± 12.5. Fifty percent of men had mild anxiety levels, while in 70% of women anxiety was moderate or high (P = 0.017). Anxiety correlated positively with intraoperative pain (R = 0.406). Multivariate logistic regression analysis revealed that anxiety was significantly associated with intraoperative pain felt by patients (OR = 4.0; 95% C.I. = 1.7-9.3; P = 0.001). CONCLUSIONS: Anxious patients were more than twice as likely to feel moderate or intense intraoperative pain during root canal treatment. To know the patient´s degree of anxiety could help the dentist to decide whether to use anxiolytic premedication and/or supplemental local anaesthesia to assure better control of pain during root canal treatment.

Silver nanoparticles are lethal to the ciliate model Tetrahymena and safe to the pike silverside Chirostoma estor.

Ciliate ectoparasites are one of the most important groups of pathogens in fish culture, and the traditional treatments are sometimes harmful to the fish and the environment. Thus, the search for novel compounds that are effective at low concentrations and safe for fish are necessary to optimise treatments in aquaculture. The antiprotozoal capacity of silver nanoparticles (AgNPs) against the ciliate Tetrahymena has been documented; however, their toxicity may vary with the synthesis methodology and nanoparticle size. The objectives of this study were a) to evaluate the acute toxicity in vitro of two AgNPs (Argovit™ and UTSA) on Tetrahymena sp., a biological model for ciliated ectoparasites of fish and b) to test the safety of lethal and higher doses of UTSA AgNPs for ciliates on the fish C. estor. Light microscopy and scanning electron microscopy (SEM) were used to determine whether AgNPs affected the structure of the cell surface of Tetrahymena. The mortality, histopathological alterations and metagenomics of the fish were used to determine the major effects of UTSA AgNPs. In Tetrahymena, the median lethal concentration (LC50) for Argovit™ was 2501 ± 1717 ng/L at 15 min and 796 ± 510 ng/L at 60 min, while the LC50 for UTSA AgNPs was 4 ± 2 and 1 ± 0.6 ng/L at 15 min and 60 min, respectively. A concentration of 3300 ng/L Argovit™ and 10.6 ng/L UTSA AgNPs for 15 and 60 min, respectively, was 100% effective against Tetrahymena. After 60 min of exposure to 0.25 and 0.50 ng/L UTSA AgNPs, the number of cilia significantly reduced, there were small holes on the cell surface, and the cellular membrane was ruptured. In fish exposed to lethal (10.6 ng/L) and higher (31.8 and 95.4 ng/L) doses of UTSA, the AgNPs did not affect fish survival after 96 h, and there were no signs of histopathological damage or gut microbial changes. This study is the first report on microscopic and ultrastructural changes in Tetrahymena after exposure to significantly low concentrations of UTSA AgNPs with antiprotozoal efficacy without evidence of harmful effects on fish. These results provide the basis for further studies of both pet aquarium and commercial fish that may validate these findings at a larger experimental scale, taking into account AgNPs bioaccumulation, safety for human consumption and environmental impact.

Impact of Physiological Signals Acquisition in the Emotional Support Provided in Learning Scenarios.

Physiological sensors can be used to detect changes in the emotional state of users with affective computing. This has lately been applied in the educational domain, aimed to better support learners during the learning process. For this purpose, we have developed the AICARP (Ambient Intelligence Context-aware Affective Recommender Platform) infrastructure, which detects changes in the emotional state of the user and provides personalized multisensorial support to help manage the emotional state by taking advantage of ambient intelligence features. We have developed a third version of this infrastructure, AICARP.V3, which addresses several problems detected in the data acquisition stage of the second version, (i.e., intrusion of the pulse sensor, poor resolution and low signal to noise ratio in the galvanic skin response sensor and slow response time of the temperature sensor) and extends the capabilities to integrate new actuators. This improved incorporates a new acquisition platform (shield) called PhyAS (Physiological Acquisition Shield), which reduces the number of control units to only one, and supports both gathering physiological signals with better precision and delivering multisensory feedback with more flexibility, by means of new actuators that can be added/discarded on top of just that single shield. The improvements in the quality of the acquired signals allow better recognition of the emotional states. Thereof, AICARP.V3 gives a more accurate personalized emotional support to the user, based on a rule-based approach that triggers multisensorial feedback, if necessary. This represents progress in solving an open problem: develop systems that perform as effectively as a human expert in a complex task such as the recognition of emotional states.

In vitro biofilm formation on different ceramic biomaterial surfaces: Coating with two bactericidal glasses.

OBJECTIVES: To compare biofilm formation on the surface of different ceramic biomaterials to be used in implant dentistry. METHODS: In vitro biofilm formation was investigated from mixtures of standard reference strains of Streptococcus oralis, Veillonella parvula, Actinomyces naeslundii, Fusobacterium nucleatum, Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis. Sterile ceramic calcium hydroxyapatite discs (HA) as control, sterile Al2O3/Ce-TZP nanocomposite sandblasted discs (material A1) and sterile Al2O3/Ce-TZP nanocomposite sandblasted discs and coated with two types of antimicrobial glasses (materials A2 and A3) were used. Biofilms were grown on the four surfaces and evaluated after 12, 24, 48 and 72 h of incubation. Biofilms were examined by confocal laser scanning microscopy (CLSM). In addition, counts of live bacterial cells of the target species A. actinomycetemcomitans, F. nucleatum and P. gingivalis were calculated by quantitative polymerase chain reaction (qPCR) combined with propidium monoazide (PMA). For data analysis, bacterial counts were compared with a multivariate general lineal model. RESULTS: Using CLSM, cell vitality decreased in A2 and A3. With qPCR-PMA, significant differences in vitality were observed forA. actinomycetemcomitans in A3 after 48 and 72 h of incubation. With respect to the development of the biofilms, a significant increase in counts on HA and materials A1 and A2 was observed for A. actinomycetemcomitans and F. nucleatum. Conversely, for P. gingivalis, no differences were found for HA and materials A1 and A2. SIGNIFICANCE: Differences in biofilm formation were detected among the different tested materials. The ceramic material A3 has an effect on the vitality of A. actinomycetemcomitans growing in an in vitro biofilm model.

Endodontics and diabetes: association versus causation.

Endodontic Medicine has gained more attention and is becoming a more important issue in Endodontics. As an example, more than one hundred articles on this topic have been published in the last eight years. Several of these studies have found an association between endodontic variables, that is the prevalence of apical periodontitis, the prevalence of root canal treatment (RCT) and the outcome of RCT assessed as root filled teeth (RFT) with radiolucent periapical lesions (RPL) or non-retained RFT, and several systemic diseases, such as diabetes, cardiovascular disease, smoking habits, osteoporosis, inherited coagulopaties, biological medications, low birth weight or physical fitness. However, the demonstration of association does not prove by itself the existence of a cause-effect relationship. Two variables can be related statistically to each other without either variable directly affecting the values of the other thus resulting in a non-causal relationship. Causality is assumed when one variable is shown to contribute to the development of the other, and its removal is shown to reduce the frequency of disease. Therefore, once a significant statistical association has been found between two variables, it is necessary to exclude the presence of bias, which would imply that the association is artefactual, and to analyse if the causation criteria defined by Hill (Proceedings of the Royal Society of Medicine 1965; 58: 295-300) are fulfilled to establish a causal relationship. Only if they are satisfied, can it be concluded that the association is causal. The aim of this study was to analyse the difference between association and causation, applying the criteria of causality to the specific case of the association between endodontic disease and diabetes mellitus.

Antibacterial effects of polymeric PolymP-n Active nanoparticles. An in vitro biofilm study.

OBJECTIVE: to study the antibacterial effect of polymeric PolymP-n Active nanoparticles using an in vitro subgingival biofilm model. METHODS: Hydroxyapatite discs coated with five modalities of nanoparticles (NPs): NPs, NPs doped with zinc, calcium, silver and doxycycline, PBS as control, and Streptococcus oralis, Actinomyces naeslundii, Veillonella parvula, Fusobacterium nucleatum, Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans were studied in a static in vitro biofilm model (12, 24, 48, and 72h). Nano-roughness of the different disc surfaces (SRa, in nm) and morphological characteristic of the biofilms (thickness (µm) and bacterial viability) were studied by different microscopy modalities. Quantitative Polymerase Chain Reaction was used to assess the effect of the nanoparticles on the bacterial load (colony forming unit per milliliter) (CFUmL-1). Analysis of variance and post-hoc testing with T3 Dunnett́s, and Student Newman Keuls correction was used. Results were considered statistically significant at p<0.05. RESULTS: Surfaces containing the different nanoparticles showed significant increments in roughness when compared to controls (p<0.05). A similar biofilm formation and dynamics was observed, although reductions in bacterial viability were detected in biofilms in contact with the different nanoparticles, more pronounced with silver and doxycycline NPs. Doxycycline-NPs biofilms resulted in unstructured biofilm formation and significantly lower number of the six species when compared with the other nanoparticles specimens and controls (p<0.001 in all cases). SIGNIFICANCE: Polymeric PolymP-n Active nanoparticles when combined with silver and doxycycline showed a significant antibacterial effect when tested in an in vitro subgingival biofilm model.