Artificial Intelligence for Caries Detection: Value of Data and Information.

If increasing practitioners' diagnostic accuracy, medical artificial intelligence (AI) may lead to better treatment decisions at lower costs, while uncertainty remains around the resulting cost-effectiveness. In the present study, we assessed how enlarging the data set used for training an AI for caries detection on bitewings affects cost-effectiveness and also determined the value of information by reducing the uncertainty around other input parameters (namely, the costs of AI and the population's caries risk profile). We employed a convolutional neural network and trained it on 10%, 25%, 50%, or 100% of a labeled data set containing 29,011 teeth without and 19,760 teeth with caries lesions stemming from bitewing radiographs. We employed an established health economic modeling and analytical framework to quantify cost-effectiveness and value of information. We adopted a mixed public-private payer perspective in German health care; the health outcome was tooth retention years. A Markov model, allowing to follow posterior teeth over the lifetime of an initially 12-y-old individual, and Monte Carlo microsimulations were employed. With an increasing amount of data used to train the AI sensitivity and specificity increased nonlinearly, increasing the data set from 10% to 25% had the largest impact on accuracy and, consequently, cost-effectiveness. In the base-case scenario, AI was more effective (tooth retention for a mean [2.5%-97.5%] 62.8 [59.2-65.5] y) and less costly (378 [284-499] euros) than dentists without AI (60.4 [55.8-64.4] y; 419 [270-593] euros), with considerable uncertainty. The economic value of reducing the uncertainty around AI's accuracy or costs was limited, while information on the population's risk profile was more relevant. When developing dental AI, informed choices about the data set size may be recommended, and research toward individualized application of AI for caries detection seems warranted to optimize cost-effectiveness.

ALPHACAL: A new user-friendly tool for the calibration of alpha-particle sources.

In this work, we present and describe the program ALPHACAL, specifically developed for the calibration of alpha-particle sources. It is therefore more user-friendly and less time-consuming than multipurpose codes developed for a wide range of applications. The program is based on the recently developed code AlfaMC, which simulates specifically the transport of alpha particles. Both cylindrical and point sources mounted on the surface of polished backings can be simulated, as is the convention in experimental measurements of alpha-particle sources. In addition to the efficiency calculation and determination of the backscattering coefficient, some additional tools are available to the user, like the visualization of energy spectrum, use of energy cut-off or low-energy tail corrections. ALPHACAL has been implemented in C++ language using QT library, so it is available for Windows, MacOs and Linux platforms. It is free and can be provided under request to the authors.

Rare earth activated yttrium aluminate phosphors with modulated luminescence.

Yttrium aluminate (Y3 A5 O12 ) was doped with different rare earth ions (i.e. Gd(3+) , Ce(3+) , Eu(3+) and/or Tb(3+) ) in order to obtain phosphors (YAG:RE) with general formula,Y3-x-a Gdx REa Al5 O12 (x = 0; 1.485; 2.97 and a = 0.03). The synthesis of the phosphor samples was done using the simultaneous addition of reagents technique. This study reveals new aspects regarding the influence of different activator ions on the morpho-structural and luminescent characteristics of garnet type phosphor. All YAG:RE phosphors are well crystallized powders containing a cubic-Y3 Al5 O12 phase as major component along with monoclinic-Y4 Al2 O9 and orthorhombic-YAlO3 phases as the impurity. The crystallites dimensions of YAG:RE phosphors vary between 38 nm and 88 nm, while the unit cell slowly increase as the ionic radius of the activator increases. Under UV excitation, YAG:Ce exhibits yellow emission due to electron transition in Ce(3+) from the 5d level to the ground state levels ((2) F5/2 , (2) F7/2 ). The emission intensity of Ce(3+) is enhanced in the presence of the Tb(3+) ions and is decreased in the presence of Eu(3+) ions due to some radiative or non-radiative processes that take place between activator ions. By varying the rare earth ions, the emission colour can be modulated from green to white and red. Copyright © 2015 John Wiley & Sons, Ltd.

Anthrax vaccine adsorbed: further evidence supporting continuing the vaccination series rather than restarting the series when doses are delayed.

Whether to restart or continue the series when anthrax vaccine doses are missed is a frequent medical management problem. We applied the noninferiority analysis model to this prospective study comparing the Bacillus anthracis protective antigen (PA) IgG antibody response and lethal toxin neutralization activity at day 28 to the anthrax vaccine adsorbed (AVA) (Biothrax®) administered on schedule or delayed. A total of 600 volunteers were enrolled: 354 in the on-schedule cohort; 246 in the delayed cohort. Differences were noted in immune responses between cohorts (p<0.0001) and among the racial categories (p<0.0001). Controlling for covariates, the delayed cohort was non-inferior to the on-schedule cohort for the rate of 4-fold rise in both anti-PA IgG concentration (p<0.0001) and TNA ED50 titers (p<0.0001); as well as the mean log10-transformed anti-PA IgG concentration (p<0.0001) and the mean log10-transformed TNA ED50 titers (p<0.0001). Providing a missed AVA dose after a delay as long as 5-7 years, elicits anti-PA IgG antibody and TNA ED50 responses that are robust and non-inferior to the responses observed when the 6-month dose is given on-schedule. These important data suggest it is not necessary to restart the series when doses of the anthrax vaccine are delayed as long as 5 or more years.

[Electrodynamics of interactions in electrolyte solutions and their biological significance].

Attention is drawn to the fact that the interaction of charges in aqueous solutions of electrolytes, such as media having physiological characteristics, depends not only on the distance between interacting charges but also on the frequency that determines their dynamics. This fact has significant consequences for some biological processes and their kinetics. The analysis of reasons for charge shielding, including the dynamic effects, shows that, even at distances exceeding the Debye length, electric interactions in systems similar to physiological are effective provided that charges move with frequencies higher than 250 MHz. For each electrolyte solution, the threshold frequency (Maxwell frequency) can be found, which determines the transition from the conducting to the dielectric mode of interactions of charges in physiological solutions.

Tratamiento con desmopresina (DDAVP) previo a la analgesia epidural del parto a una paciente con enfermedad de von Willebrand tipo 1 / Desmopressin treatment before obstetric epidural analgesia for a woman with von Willebrand disease type 1

Una paciente de 33 años de edad, primigesta, afecta de enfermedad de von Willebrand tipo I fue admitida para parto a las 37 semanas de gestación solicitando analgesia epidural. Tras consulta con el Servicio de Hematología se decidió realizar tratamiento con desmopresina (DDAVP) previo a la colocación del catéter epidural. Se procedió a una infusión intravenosa de desmopresina de 0,3 Mg/Kg. Tras la infusión, se colocó un catéter epidural a nivel L3L4. Se utilizó una infusión de 0,1 por ciento de bupivacaína con 2 Mg/:m1 de fentanilo, a 12 ml/h, 4 horas más tarde la paciente fue llevada a quirófano para extracción fetal mediante fórceps de un niño sano, pasada una hora la paciente había recuperado el tono motor normal y posteriormente la sensibilidad normal en las extremidades inferiores. El catéter fue entonces retirado, sin signos de sangrado.La parturienta con enfermedad de von Willebrand puede beneficiarse de un bloqueo epidural para analgesia del parto. La decisión de realizar el bloqueo debe ser individualizada, basándose en las pruebas de coagulación. La desmopresina (DDAVP) puede tener un papel en la mejoría de la situación hematológica. (AU)

[Treatment with desmopressin before epidural anesthesia in a patient with type I von Willebrand disease]. / Tratamiento con desmopresina (DDAVP) previo a la analgesia epidural del parto a una paciente con enfermedad de von Willebrand tipo I.

A 33-year-old primipara with von Willebrand disease type I was admitted in labor at 37 weeks, requesting epidural analgesia. The consultant hematologist advised treating with desmopressin acetate (DDAVP) before inserting an epidural catheter. Desmopressin at a dose of 0.3 microgram/Kg was administered intravenously and the catheter was inserted to L3-L4 to infuse 0.1% bupivacaine with 2 micrograms/mL of fentanyl at a rate of 12 mL/h. Four hours later the patient was brought to the operating room for forceps delivery of a healthy boy. One hour later, she had recovered normal motor tone followed by normal sensitivity in the lower extremities. The catheter was then withdrawn with no signs of bleeding. A woman with von Willebrand's disease can receive an epidural block for analgesia during childbirth. The decision to perform the block should be individualized, based on coagulation tests. DDAVP may play a role in improving hemostasis.

Role of co-solute in biomolecular stability: glucose, urea and the water structure.

We have studied the action of urea and glucose on the stability of DNAand micelles. We measured the melting temperature of aqueous solutionsof DNA with urea or glucose as a co-solute; we have also measured thechanges in the critical micelle concentrations (cmc) of Sodium DodecylSulfate and Triton X-100 by addition of urea and glucose. Ourexperimental results show that glucose increases the melting temperature ofDNA and decreases the cmc, while urea acts in the contrary direction. The effects of urea and glucose on the stability of DNA and micelles canbe explained by the weakening and enhancement of hydrophobicinteractions, respectively. These effects on hydrophobic interactions arediscussed in this paper.

Decompressive craniotomy in medically uncontrollable malignant infarction.

Patients with progressive neurological deficit following large cerebral infarctions are viewed to have a uniformly poor prognosis. We present two patients with large middle cerebral artery infarctions in which a decompressive craniotomy was life saving and resulted in functional outcome. The clinical course of patients with malignant infarction and the treatment issues involved including patient selection and the timing and extent of cranial decompression are discussed.

Production of guanine from NH(4)CN polymerizations.

The synthesis of adenine from the polymerization of concentrated ammonium cyanide solutions is well known. We show here that guanine is also produced by this reaction but at yields ranging from 10 to 40 times less than that of adenine. This synthesis is effective at both +80 and -20 degrees C. Since high concentrations of NH(4)CN are obtainable only by freezing, this prebiotic synthesis would be applicable to frozen regions of the primitive Earth, the Jovian satellite Europa and other icy satellites, and the parent body of the Murchison meteorite.

Clinical case definitions for Argentine hemorrhagic fever.

Argentine hemorrhagic fever (AHF) is a potentially lethal infection in Argentina. The case-fatality ratio is >15%, but treatment reduces the mortality rate to <1%. Diagnosis is based on clinical and laboratory criteria, but no case definition has been validated. A chart review was conducted for patients hospitalized with suspected AHF. Individuals with a fourfold rise in antibody titer were classified as cases. The combination of a platelet count of <100,000/mm3 and a white blood cell (WBC) count of <2,500/mm3 had a sensitivity and specificity of 87% and 88%, respectively, thus suggesting that the use of these criteria in a case definition would be helpful for epidemiological studies of AHF. The combination of a platelet count of <100,000/mm3 and a WBC count of <4,000/mm3 had a sensitivity of 100% and a specificity of 71%; the use of these criteria in a case definition should be helpful for screening patients for therapy with immune plasma in the region where AHF is endemic.

Balloon device for experimental graded spinal cord compression in the rat.

We have developed a balloon device that creates reproducible graded compression of the rat spinal cord. It uses a modified Camino intracranial pressure monitor bolt with a small latex balloon attached to the tip. The device is affixed to the spinous processes of two cervicothoracic vertebrae and positioned directly over an exposed segment of spinal cord. Ten compression balloons were tested and revealed reproducible pressure transmission at expansion volumes from 0.12 to 0.34 cc. Reversible graded spinal cord compression was verified by monitoring cortical somatosensory and motor evoked potentials before, during, and after cord compression. The pathophysiologic changes occurring with graded compression and the effect of therapeutic interventions can be studied in a rat model.

Protective efficacy of a live attenuated vaccine against Argentine hemorrhagic fever. AHF Study Group.

Argentine hemorrhagic fever (AHF), caused by the arenavirus Junin, is a major public health problem among agricultural workers in Argentina. A prospective, randomized, double-blind, placebo-controlled, efficacy trial of Candid 1, a live attenuated Junin virus vaccine, was conducted over two consecutive epidemic seasons among 6500 male agricultural workers in the AHF-endemic region. Twenty-three men developed laboratory-confirmed AHF during the study; 22 received placebo and 1 received vaccine (vaccine efficacy 95%; 95% confidence interval [CI], 82%-99%). Three additional subjects in each group developed laboratory-confirmed Junin virus infection associated with mild illnesses that did not fulfill the clinical case definition for AHF, yielding a protective efficacy for prevention of any illness associated with Junin virus infection of 84% (95% CI, 60%-94%). No serious adverse events were attributed to vaccination. Candid 1, the first vaccine for the prevention of illness caused by an arenavirus, is safe and highly efficacious.

Experience with transcranial magnetic stimulation in cortical mapping.

Seventeen subjects underwent transcranial magnetic stimulation (TMS) toward cortical mapping. Cortical mapping produced scalp representations of five upper extremity muscles, and their spatial orientation tended to support an expected anatomic pattern. Muscle map locations and map areas showed trends across musical skill and hand dominance, as well. No subject experienced adverse effects during the study. TMS promises to be an effective tool for noninvasive cortical mapping.

Primary sources of phosphorus and phosphates in chemical evolution.

In this work we consider the role of phosphorus in chemical evolution from an interdisciplinary approach. First we briefly review the presence of this element in different cosmic sites, such as massive stellar cores, circumstellar and interstellar clouds, meteorites, lunar and Martian samples, interplanetary dust particles, cometary dust and planetary atmospheres. Thus we illustrate the fact that phosphorus seems to be, at the same time, scarce and ubiquitous in the solar system. Afterwards, by comparing the phosphorus content of our planet's main reservoirs with the amount of cometary and meteoritic matter captured by the primitive Earth, we conclude that comets may have provided a primary source for phosphorus compounds of prebiotic interest. Finally, we make a number of proposals aimed to gain observational supporting evidence to the above conclusion and other suggestions made in the article.

Characterization of Oliveros virus, a new member of the Tacaribe complex (Arenaviridae: Arenavirus).

Oliveros virus is an agent isolated in cell culture from Bolomys obscurus (Rodentia, Muridae, Sigmodontinae) captured on the central Argentine pampa. Oliveros virus was shown to be related to members of the Tacaribe complex of the family Arenaviridae by immunofluorescent antibody (IFA) tests, electrophoretic pattern of viral proteins, and morphology as observed by electron microscopy. It was distinct from 12 other arenaviruses by a combination of plaque-reduction neutralization tests, comparison of endpoint titers among cross-IFA tests, and comparison of viral RNA sequence data. This agent is the third new arenavirus from South America described within the last three years.

Suppression of spinal and cortical somatosensory evoked potentials by desflurane anesthesia.

The effect of the volatile anesthetic desflurane on spinal and cortical somatosensory evoked potentials (SEPs) was examined in 11 Sprague-Dawley male rats. Platinum recording electrodes were placed stereotactically over the left somatosensory cortex and dorsal midline of the T11-12 spinal cord while the right posterior tibial nerve was stimulated at twice motor threshold. The effect of desflurane was examined at various concentrations ranging from 0.7 to 11.4% (2 MAC). Mean arterial blood pressure (MAP) decreased (p = 0.001) progressively with increasing end-tidal desflurane concentrations. Concentrations of 1.4% (1/4 MAC) and 2.8% (1/2 MAC) did not significantly affect the spinal SEP (SSEP) amplitude or the latency. With higher concentrations, there was a progressive decrease in amplitude of the cortical SEPs (CSEPs; p = 0.002) and SSEPs (p = 0.008). However, CSEP and SSEP latencies did not change. At 5.7% (1 MAC), three animals (33%) lost CSEPs while SSEPs remained intact. At 11.4% (2 MAC), the CSEPs were lost in all animals. Only one rat lost the SSEPs at the 2 MAC concentration of desflurane, indicating the resistance of the SSEPs to desflurane anesthesia. We conclude that desflurane anesthesia significantly alters the amplitude of SSEPs and CSEPs without a significant change in the peak latency.