Atrial fibrillation ablation techniques

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RHYTHM-AF: design of an international registry on cardioversion of atrial fibrillation and characteristics of participating centers

BACKGROUND Atrial fibrillation is a serious public health problem posing a considerable burden to not only patients, but the healthcare environment due to high rates of morbidity, mortality, and medical resource utilization. There are limited data on the variation in treatment practice patterns across different countries, healthcare settings and the associated health outcomes. METHODS/DESIGN RHYTHM-AF was a prospective observational multinational study of management of recent onset atrial fibrillation patients considered for cardioversion designed to collect data on international treatment patterns and short term outcomes related to cardioversion. We present data collected in 10 countries between May 2010 and June 2011. Enrollment was ongoing in Italy and Brazil at the time of data analysis. Data were collected at the time of atrial fibrillation episode in all countries (Australia, Brazil, France, Germany, Italy, Netherlands, Poland, Spain, Sweden, United Kingdom), and cumulative follow-up data were collected at day 60 (±10) in all but Spain. Information on center characteristics, enrollment data, patient demographics, detail of atrial fibrillation episode, medical history, diagnostic procedures, acute treatment of atrial fibrillation, discharge information and the follow-up data on major events and rehospitalizations up to day 60 were collected. DISCUSSIN A total of 3940 patients were enrolled from 175 acute care centers. 70.5% of the centers were either academic (44%) or teaching (26%) hospitals with an overall median capacity of 510 beds. The sites were mostly specialized with anticoagulation clinics (65.9%), heart failure (75.1%) and hypertension clinics (60.1%) available. The RHYTHM-AF registry will provide insight into regional variability of antiarrhythmic and antithrombotic treatment of atrial fibrillation, the appropriateness of such treatments with respect to outcomes, and their cost-efficacy. Observations will help inform strategies to improve cardiovascular outcomes in patients with atrial fibrillation. TRIAL REGISTRATION Clinical trials NCT01119716Harry JGM Crijns, Lori D Bash, François Chazelle, Jean-Yves Le Heuzey, Thorsten Lewalter, Gregory YH Lip, Aldo P Maggioni, Alfonso Martín, Piotr Ponikowski, Mårten Rosenqvist, Prashanthan Sanders, Mauricio Scanavacca, Alexandra A Bernhardt, Sreevalsa Unniachan, Hemant M Phatak and Anselm K Git

Motivated learning with digital learning tasks: what about autonomy and structure?

Article about Motivated learning with digital learning tasks: what about autonomy and structure

Insight into the proteome of the hyperthermophilic Crenarchaeon Ignicoccus hospitalis: the major cytosolic and membrane proteins

Ignicoccus hospitalis, a hyperthermophilic, chemolithoautotrophic Crenarchaeon, is the host of Nanoarchaeum equitans. Together, they form an intimate association, the first among Archaea. Membranes are of fundamental importance for the interaction of I. hospitalis and N. equitans, as they harbour the proteins necessary for the transport of macromolecules like lipids, amino acids, and cofactors between these organisms. Here, we investigated the protein inventory of I. hospitalis cells, and were able to identify 20 proteins in total. Experimental evidence and predictions let us conclude that 11 are soluble cytosolic proteins, eight membrane or membrane-associated proteins, and a single one extracellular. The quantitatively dominating proteins in the cytoplasm (peroxiredoxin; thermosome) antagonize oxidative and temperature stress which I. hospitalis cells are exposed to at optimal growth conditions. Three abundant membrane protein complexes are found: the major protein of the outer membrane, which might protect the cell against the hostile environment, forms oligomeric complexes with pores of unknown selectivity; two other complexes of the cytoplasmic membrane, the hydrogenase and the ATP synthase, play a key role in energy production and conversion

An Evolutionary Upgrade of Cognitive Load Theory: Using the Human Motor System and Collaboration to Support the Learning of Complex Cognitive Tasks

Cognitive load theory is intended to provide instructional strategies derived from experimental, cognitive load effects. Each effect is based on our knowledge of human cognitive architecture, primarily the limited capacity and duration of a human working memory. These limitations are ameliorated by changes in long-term memory associated with learning. Initially, cognitive load theory's view of human cognitive architecture was assumed to apply to all categories of information. Based on Geary's (Educational Psychologist 43, 179-195 2008; 2011) evolutionary account of educational psychology, this interpretation of human cognitive architecture requires amendment. Working memory limitations may be critical only when acquiring novel information based on culturally important knowledge that we have not specifically evolved to acquire. Cultural knowledge is known as biologically secondary information. Working memory limitations may have reduced significance when acquiring novel

Analiza proteinskih adukata kao biomarkera kratkotrajne izloženosti etilen oksidu i rezultati biomonitoringa

An accidental exposure of six workers to ethylene oxide (EO) provided the rationale for a biomonitoring and follow-up study, whose aim was to analyse protein adduct kinetics and examine the differentiation between accidental and environmental exposure, e.g., from tobacco smoke. For this purpose, the decrease in the concentration of the haemoglobin adduct N-2-hydroxyethylvaline (HEV) was followed during a fi ve-month period after the accident, together with N-2-cyanoethylvaline (CEV) and urinary cotinine, two well-established biomarkers for smoking. The follow-up study showed that EO adduct concentrations significantly increased after a short but presumably high exposure. Initial biomonitoring revealed HEV levels above 500 pmol g-1 globin in all cases, with a maximum of about 2,400 pmol g-1 globin. This compares to a German EKA value (exposure equivalent for carcinogenic substances) for a daily 8-h-exposure to 1 ppm EO of 90 μg L-1 blood (~3,900 pmol g-1 globin). The adduct levels dropped in accordance with the expected zero-order kinetics for a single exposure. After the five-month observation interval, the HEV concentrations in blood refl ected the individual background from tobacco smoking. The results of this study show that even a short exposure to ethylene oxide may result in a signifi cant rise in haemoglobin adduct levels. Although protein adducts and their occupational-medical assessment values are considered for long-term exposure surveillance, they can also be used for monitoring accidental exposures. In these cases, the calculation of daily ‘ppm-equivalents’ may provide a means for a comparison with the existing assessment values.U radu su prikazani rezultati biomonitoringa provedenog neposredno nakon akcidentalnog izlaganja šestorice radnika etilen oksidu i studije praćenja (follow up) provedene u cilju procjene kinetike razgradnje proteinskih adukata i utvrđivanja razlika nakon kratkotrajne izloženosti i izlaganja čimbenicima iz okoliša kao što je duhanski dim. U tu smo svrhu tijekom petomjesečnoga razdoblja nakon nezgode pratili smanjenje koncentracije hemoglobinskog adukta N-2-hidroksietilvalina usporedo s mjerenjem razina N-2-cijanoetilvalina i kotinina u mokraći, koji su pouzdani biomarkeri za dokazivanje pušenja duhana. Studija praćenja je pokazala da su koncentracije adukata etilen oksida značajno porasle nakon kratkotrajnoga izlaganja visokoj razini etilen oksida. U početnom biomonitoringu svih radnika izmjerene su razine N-2-hidroksietilvalina iznad 500 pmol g-1 globina, s maksimalnom vrijednošću od oko 2400 pmol g-1 globina. Ti su podaci usporedivi s vrijednostima njemačkih normi ekvivalenata izlaganja kancerogenim tvarima (EKA) od 90 μg L-1 krvi (~3900 pmol g-1 globina) kroz osmosatno dnevno izlaganje koncentraciji od 1 ppm etilen oksida. Razine adukata smanjile su se u skladu s očekivanom kinetikom nultoga reda za jednokratno izlaganje. Koncentracije N-2-hidroksietilvalina izmjerene u krvi radnika nakon petomjesečnoga praćenja mogu se povezati s njihovim osobnim pušačkim navikama. Rezultati toga istraživanja pokazuju da čak i kratkotrajna izloženost etilen oksidu može znatno povisiti razine adukata hemoglobina. Premda se u zdravstvenom nadzoru u okviru medicine rada proteinski adukti i njihove vrijednosti razmatraju u procjeni dugotrajnoga izlaganja, oni se mogu koristiti i za praćenje akcidentalnih izlaganja. U tim slučajevima izračun dnevnih vrijednosti (tzv. ppm-ekvivalenata) može poslužiti za usporedbu s postojećim procijenjenim vrijednostima

The Complete Genome Sequence of Thermoproteus tenax: A Physiologically Versatile Member of the Crenarchaeota

Here, we report on the complete genome sequence of the hyperthermophilic Crenarchaeum Thermoproteus tenax (strain Kra 1, DSM 2078(T)) a type strain of the crenarchaeotal order Thermoproteales. Its circular 1.84-megabase genome harbors no extrachromosomal elements and 2,051 open reading frames are identified, covering 90.6% of the complete sequence, which represents a high coding density. Derived from the gene content, T. tenax is a representative member of the Crenarchaeota. The organism is strictly anaerobic and sulfur-dependent with optimal growth at 86 degrees C and pH 5.6. One particular feature is the great metabolic versatility, which is not accompanied by a distinct increase of genome size or information density as compared to other Crenarchaeota. T. tenax is able to grow chemolithoautotrophically (CO2/H-2) as well as chemoorganoheterotrophically in presence of various organic substrates. All pathways for synthesizing the 20 proteinogenic amino acids are present. In addition, two presumably complete gene sets for NADH:quinone oxidoreductase (complex I) were identified in the genome and there is evidence that either NADH or reduced ferredoxin might serve as electron donor. Beside the typical archaeal A(0)A(1)-ATP synthase, a membrane-bound pyrophosphatase is found, which might contribute to energy conservation. Surprisingly, all genes required for dissimilatory sulfate reduction are present, which is confirmed by growth experiments. Mentionable is furthermore, the presence of two proteins (ParA family ATPase, actin-like protein) that might be involved in cell division in Thermoproteales, where the ESCRT system is absent, and of genes involved in genetic competence (DprA, ComF) that is so far unique within Archaea