Common therapeutic approaches in sleep and awake bruxism — an overview

Bruxism, a common medical condition characterised by clenching or grinding of the teeth and/or by bracing or thrusting of the mandible, can occur during sleep, when it is known as sleep bruxism (SB), or during wakefulness, when it is known as awake bruxism (AB). Although bruxism often causes headaches, temporomandibular joint pain, masticatory muscle pain, mechanical tooth wear, prosthodontic complications and cracked teeth, there is still not enough data to define and support a standardised approach to its treatment. The aim of this review was to present the pathophysiology, consequences, types and treatment methods of bruxism in order to increase readers’ knowledge of this topic. Differences between awake and nocturnal bruxism are included, as well as risk factors and indicators visible during the clinical examination of affected patients. Among the causes we consider are genetics, stress, oral parafunctions and changes in the Central Nervous System (CNS). Potential and common methods of treatment are presented, along with suggested guidelines that should be followed when determining an appropriate treatment method. We draw attention to the notably dynamic development of bruxism in today’s society and the importance of informational and preventive projects, especially those targeted at high-risk patients as well as those targeted at specialists, in order to better tackle the bruxism ‘epidemic’

Interferon-Gamma Release Assays in the diagnosis of latent tuberculosis infection in clinical situations

Przez wiele lat podstawowym testem identyfikującym latentne (utajone) zakażenie prątkami gruźlicy (LTBI) była próba tuberkulinowa, posiadająca pewne ograniczenia, które wynikają przede wszystkim z niskiej czułości i specyficzności. Obecnie stosuje się testy IGRA z krwi obwodowej, umożliwiające szybką diagnostykę LTBI poprzez pomiar interferonu gamma (IFN-g) wydzielanego przez limfocyty T pobudzone swoistymi dla Mycobacterium tuberculosis antygenami. Wykrywanie LTBI ma istotne znaczenie w kontroli osób potencjalnie zagrożonych zachorowaniem na gruźlicę, na przykład przebywających w bliskim kontakcie z chorymi prątkującymi oraz dla pacjentów kwalifikowanych do leczenia lekami biologicznymi. W pracy przedstawiono 3 wybrane sytuacje kliniczne, w których zastosowano testy IGRA. W dwóch przypadkach rozpoznano ostatecznie utajone zakażenie prątkami gruźlicy, a w jednym aktywną gruźlicę.Until recently, the basic test to identify latent tuberculosis infection (LTBI) was the tuberculin skin test, despite its limitations in the form of low sensitivity and specificity. Currently, Interferon Gamma Release Assays from peripheral blood are used for a rapid diagnosis of LTBI and measurement of the interferon gamma (IFN-g) levels secreted by specific T cells stimulated with Mycobacterium tuberculosis antigens. Detection of LTBI is important in the control of people potentially at risk of TB disease, such as people remaining in close contact with BK (+) tb patient and for patients evaluated for biological treatment. The paper presents the value of IGRA in three selected clinical situations: in two cases of latent tuberculosis infection and in one case of active tuberculosis

Polimorfizm w genie N-acetylotransferazy 2 u chorych na raka płuca. Doniesienie wstępne

Introduction: Individual’s risk of developing lung cancer depends not only on exposure to tobacco smoke, but also on the activity of enzymes involved in the activation or deactivation of carcinogens. Arylamine N-acetyltransferase (EC 2.3.1.5) is an enzyme involved in biotransformation of xenobiotics, mainly aromatic and heterocyclic amines and hydrazines. The different acetylation phenotypes within a population are derived from mutations in the NAT 2 gene. These mutations influence the activity (specifically resulting in high or low activity) of the NAT enzyme. Some authors have demonstrated lung cancer predisposing role of slow acetylator phenotype, whereas other reported increased lung cancer risk for fast acetylators or neutral effect of the NAT2 polymorphism. The aim of this preliminary report was to determine the NAT2 gene polymorphism in patients with lung cancer. Material and methods: 39 patients with inoperable lung cancer (29 — NSCLC and 10 — SCLC), median age 59 years (42– –72) entered the study. Acetylation genotype was determined in the genomic DNA using an allele-specific polymerase chain reaction. We investigated four genetic mutations, C481T, G590A, A803G i G857A, of the gene NAT2. Results: There were 10 different NAT2 genotypes among the 39 patients. Fourteen patients with a NAT2*2 4/4, *4/5, *4/6 and *4/7 were classified as fast acetylators; and 25 patients with a NAT2*5/5, *5/6, *5/7, *6/6, *6/7 or *7/7 genotype were classified as slow acetylators. Among the 10 patients with SCLC — 4 were fast acetylators, and among 29 patients with NSCLC dominated slow acetylation type found in 19 patients (genotypes NAT2 *5/5 and NAT2 *5/6). Conclusions: Among patients with small cell lung cancer, there was no predominance of genotype of acetylation, whereas among patients with non-small cell lung cancer predominated NAT2*5/5 and NAT2*5/6 genotypes (slow acetylators).Wstęp: Indywidualne ryzyko zachorowania na raka płuca zależy nie tylko od ekspozycji na dym tytoniowy, ale również od aktywności enzymów biorących udział w aktywacji lub deaktywacji substancji rakotwórczych. Arylamino N-acetylotransferazy (EC 2.3.1.5) są enzymami biorącymi udział w biotransformacji ksenobiotyków, amin aromatycznych i heterocyklicznych oraz hydrazyn. Zaobserwowane różnice w aktywności enzymu i szybkości metabolizowania substancji zależnych od N-acetylotransferazy 2 (NAT2) powiązano z polimorfizmem genu kodującego ten enzym. Niektórzy autorzy wskazują na wolny typ acetylacji, jako predysponujący do wystąpienia raka płuca, podczas gdy inni wykazują brak wpływu polimorfizmu NAT2 lub większe ryzyko raka płuca wśród szybkich acetylatorów. Celem pilotażowego badania była ocena polimorfizmu genu NAT2 umożliwiającego określenie typu acetylacji u chorych na raka płuca. Materiały i metody: Badaną grupę stanowiło 39 chorych na nieoperacyjnego raka płuca (29 — rak niedrobnokomórkowy, 10 — rak drobnokomórkowy), mediana wieku wynosiła 59 lat (42–72 lata). Do badania pobierano 5 ml krwi. Genotyp NAT2 został określony na podstawie identyfikacji czterech mutacji, C481T, G590A, A803G i G857A. Wyniki: W przebadanej grupie 39 chorych zidentyfikowano występowanie 10 różnych genotypów NAT2. Czternastu chorych z genotypami NAT2 *4/4, *4/5, *4/6 i *4/7 zostało sklasyfikowanych jako szybcy acetylatorzy a 25 z genotypami NAT2 *5/ 5, *5/6, *5/7, *6/6, *6/7 lub *7/7 jako wolni acetylatorzy. Wśród 10 chorych na DRP — 4 chorych to szybcy acetylatorzy, zaś wśród 29 chorych na NDRP dominował wolny typ acetylacji stwierdzony u 19 chorych (genotypy NAT2*5/5 i NAT2*5/6). Wnioski: Wśród chorych na drobnokomórkowego raka płuca nie stwierdzono dominacji określonego genotypu acetylacji, natomiast wśród chorych na niedrobnokomórkowego raka płuca przeważali pacjenci z genotypami NAT2*5/5 i NAT2*5/6 (wolni acetylatorzy)

Towards an optimization of stimulus parameters for brain-computer interfaces based on steady state visual evoked potentials.

Efforts to construct an effective brain-computer interface (BCI) system based on Steady State Visual Evoked Potentials (SSVEP) commonly focus on sophisticated mathematical methods for data analysis. The role of different stimulus features in evoking strong SSVEP is less often considered and the knowledge on the optimal stimulus properties is still fragmentary. The goal of this study was to provide insight into the influence of stimulus characteristics on the magnitude of SSVEP response. Five stimuli parameters were tested: size, distance, colour, shape, and presence of a fixation point in the middle of each flickering field. The stimuli were presented on four squares on LCD screen, with each square highlighted by LEDs flickering with different frequencies. Brighter colours and larger dimensions of flickering fields resulted in a significantly stronger SSVEP response. The distance between stimulation fields and the presence or absence of the fixation point had no significant effect on the response. Contrary to a popular belief, these results suggest that absence of the fixation point does not reduce the magnitude of SSVEP response. However, some parameters of the stimuli such as colour and the size of the flickering field play an important role in evoking SSVEP response, which indicates that stimuli rendering is an important factor in building effective SSVEP based BCI systems

On the quantification of SSVEP frequency responses in human EEG in realistic BCI conditions.

This article concerns one of the most important problems of brain-computer interfaces (BCI) based on Steady State Visual Evoked Potentials (SSVEP), that is the selection of the a-priori most suitable frequencies for stimulation. Previous works related to this problem were done either with measuring systems that have little in common with actual BCI systems (e.g., single flashing LED) or were presented on a small number of subjects, or the tested frequency range did not cover a broad spectrum. Their results indicate a strong SSVEP response around 10 Hz, in the range 13-25 Hz, and at high frequencies in the band of 40-60 Hz. In the case of BCI interfaces, stimulation with frequencies from various ranges are used. The frequencies are often adapted for each user separately. The selection of these frequencies, however, was not yet justified in quantitative group-level study with proper statistical account for inter-subject variability. The aim of this study is to determine the SSVEP response curve, that is, the magnitude of the evoked signal as a function of frequency. The SSVEP response was induced in conditions as close as possible to the actual BCI system, using a wide range of frequencies (5-30 Hz, in step of 1 Hz). The data were obtained for 10 subjects. SSVEP curves for individual subjects and the population curve was determined. Statistical analysis were conducted both on the level of individual subjects and for the group. The main result of the study is the identification of the optimal range of frequencies, which is 12-18 Hz, for the registration of SSVEP phenomena. The applied criterion of optimality was: to find the largest contiguous range of frequencies yielding the strong and constant-level SSVEP response

SSVEP responses to circle and square stimuli; organization of the plot as in <b>Figure 2</b>.

<p>SSVEP responses to circle and square stimuli; organization of the plot as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0112099#pone-0112099-g002" target="_blank"><b>Figure 2</b></a>.</p

SSVEP responses to stimuli with and without fixation point; organization of the plot as in <b>Figure 2</b>.

<p>SSVEP responses to stimuli with and without fixation point; organization of the plot as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0112099#pone-0112099-g002" target="_blank"><b>Figure 2</b></a>.</p

SSVEP responses to stimuli of different colours; organization of the plot as in <b>Figure 2</b>.

<p>SSVEP responses to stimuli of different colours; organization of the plot as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0112099#pone-0112099-g002" target="_blank"><b>Figure 2</b></a>.</p

SSVEP responses to stimuli of different sizes; organization of the plot as in <b>Figure 2</b>.

<p>SSVEP responses to stimuli of different sizes; organization of the plot as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0112099#pone-0112099-g002" target="_blank"><b>Figure 2</b></a>.</p

The results of post-hoc Wilcoxon signed-rank for comparison of SSVEP magnitude pairs evoked by different coloured stimuli in experiment I.

<p>The results of post-hoc Wilcoxon signed-rank for comparison of SSVEP magnitude pairs evoked by different coloured stimuli in experiment I.</p