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Background Atrial fibrillation (AF) promotes electrical, neurohormonal and structural remodeling of atria and ventricles. Long lasting AF leads to atrial interstitial fibrosis, apoptosis, loss of myofibrils and finally to heart failure (HF). Purpose The aim of the study was impact of aldosterone antagonist, spironolactone, on exercise tolerance and neurohormonal activity in patients with permanent AF without symptoms of HF. Methods In prospective, randomized study patients with permanent AF at least for 1 year, no signs and symptoms of HF and stable clinical condition were included. Patients were randomized to: beta-blocker plus spironolactone (dose: 25 mg) treatment and rate-control treatment with only beta-blocker. Propranolol, metoprolol and bisoprolol were used, doses were adjusted to achieve resting heart rate 60–80/min. Ergospirometry (CPX) and 6-minute walk (6-MWT) tests were performed during separate days. Results Study group consisted of 49 patients, 69% men, mean age 62.1±9.6 without structural and chronic active diseases, mean time of arrhythmia was 5.5 years, Q1: 2, Q3: 8 years. Follow-up was 11.2 months. All patients were treated with beta-blockers, 27 patients were treated with 25 mg spironolactone. Surprisingly physical capacity in 6-minute walk test (6-MWT) in studied patients was not significantly reduced in comparison with values ranges for healthy volunteers. After 11.2 months follow-up significantly longer exercise time (433±113 vs. 367±162 sec, p Conclusions In patients with permanent atrial fibrillation cardiopulmonary exercise responses were markedly abnormal, but exercise capacity was increased after spironolactone treatment. Deterioration of spirometry results might be due to beta-blocker treatment. In spironolactone treated group BNP levels were significantly lower what may correspond to its heart failure protective activity.

The calcareous soils in the San Bernardino National Forest host a group of endemic plant species, including five listed as federally endangered. The parent material for these soils is a very pure deposit of magnesium and calcium carbonate that is being actively mined. The mining operations produce copious quantities of dust. This study evaluated the quantity of dust moving across the landscape and depositing to the ecosystems, and the effect of carbonate dust on physiological parameters of a plant species acting as a surrogate for the endangered species. Most of the dust was found to deposit within one kilometer of the mining operations. Plants growing within the deposition zone had lower photosynthetic activity and less vigorous growth patterns. Several mitigation measures are recommended.

Toxoplasma gondii is an obligate intracellular parasite that actively invades mammalian cells using a unique form of gliding motility that critically depends on actin filaments in the parasite. To determine if parasite motility is driven by a myosin motor, we examined the distribution of myosin and tested the effects of specific inhibitors on gliding and host cell invasion. A single 90 kDa isoform of myosin was detected in parasite lysates using an antisera that recognizes a highly conserved myosin peptide. Myosin was localized in T. gondii beneath the plasma membrane in a circumferential pattern that overlapped with the distribution of actin. The myosin ATPase inhibitor, butanedione monoxime (BDM), reversibly inhibited gliding motility across serum-coated slides. The myosin light-chain kinase inhibitor, KT5926, also blocked parasite motility and greatly reduced host cell attachment; however, these effects were primarily caused by its ability to block the secretion of microneme proteins, which are involved in cell attachment. In contrast, while BDM partially reduced cell attachment, it prevented invasion even under conditions in which microneme secretion was not affected, indicating a potential role for myosin in cell entry. Collectively, these results indicate that myosin(s) probably participate(s) in powering gliding motility, a process that is essential for cell invasion by T. gondii.

Toxoplasma gondii is an obligate intracellular parasite that invades a wide range of vertebrate host cells. We demonstrate that invasion is critically dependent on actin filaments in the parasite, but not the host cell. Invasion into cytochalasin D (CD)-resistant host cells was blocked by CD, while parasite mutants invaded wild-type host cells in the presence of drug. CD resistance in Toxoplasma was mediated by a point mutation in the single-copy actin gene ACT1. Transfection of the mutant act1 allele into wild-type Toxoplasma conferred motility and invasion in the presence of CD. We conclude that host cell invasion by Toxoplasma, and likely by related Apicomplexans, is actively powered by an actin-based contractile system in the parasite.

We report a study of digital alloy quantum wells of CdSe/ZnSe grown by migration enhanced epitaxy. The quantum well regions consist of various numbers of periods of one monolayer of CdSe and three monolayers of ZnSe, and the barriers are ZnSe. It will be shown that the optical properties of such quantum wells are greatly affected by the structural quality of the digital alloy. Both structural and optical properties will be discussed. Such digital alloy quantum wells are shown to have excellent room temperature optical characteristics.

The ground control of the third and fourth China-Brazil Earth Resources Satellites (CBERS 3 and 4) will be carried out by a new system under development at INPE. This system will include new technologies to reduce cost s and development time of future ground system projects, through shared or adaptable softwa re. Taking advantage of the experience gained in earlier ground control systems, the entit ies related to satellite operations activities have been modeled as metadata. This modeling approach will increase the systemss reusability, reducing the efforts required to make changes. Whenever modeling costs of entities via metadata have been become unfeasible, their programming interfaces have been defined by Design Patterns in order to facilitate f uture changes. Furthermore, the telecommand and telemetry subsystems architecture includes a processing kernel, which can be shared with EGSE and satellite simulation softwa re. This architecture also foresees the inclusion of CCSDS communication link protocols in other INPE satellite missions. In the future, this system will be upgraded to include Art ificial Intelligence (AI) techniques, like Planning, to prepare flight operation plans for the routine phase of the missions. The engineers in charge of planning the satellite opera tions will use tools developed with Dynamic Object Model technology to define the opera tions activities. Through the high-level script language supplied by these tools, the engine ers will be able to define and/or change the knowledge database of operations activities, withou t requiring specific software development for each satellite. In addition, these tools will m ake it easier to define planning goals and to edit existing planning to deal with non-routine ope rations activities. The operations plan will have actions that are automatically executed by the system, as well as actions that are manually executed by human operators. This paper presents the modeling of the operations entities to increase the satellite control systems reusability and provide software that may be used by the control center, testing (EGSE), and sim ulation systems. This paper also shows how the Dynamic Object Model and AI technologies will be added to the system in order to automate the control center operations, thereby red ucing operations cost.

A botanist by education, Jan M. Dobrowolski devoted his whole life to the advancement of pharmacy. Working at the universities of Warsaw and Poznań, he organized medicinal herbs cultivation projects, for which he developed a theoretical basis. He also gave lectures for students of pharmacy, taking care to provide them with a comprehensive and modern eduction. Some of the less known episodes of his life include his participation in the formation of the scouting movement in Poland, his religious and ethical activity, his journalistic experiences, and his role in organizing mass-scale collection of medicinal herbs in the years of the Second World War. After the war he continued his research as well as organizational and didactic work at the University of Poznań.