20 research outputs found
Potentiation of thrombus instability: a contributory mechanism to the effectiveness of antithrombotic medications
© The Author(s) 2018The stability of an arterial thrombus, determined by its structure and ability to resist endogenous fibrinolysis, is a major determinant of the extent of infarction that results from coronary or cerebrovascular thrombosis. There is ample evidence from both laboratory and clinical studies to suggest that in addition to inhibiting platelet aggregation, antithrombotic medications have shear-dependent effects, potentiating thrombus fragility and/or enhancing endogenous fibrinolysis. Such shear-dependent effects, potentiating the fragility of the growing thrombus and/or enhancing endogenous thrombolytic activity, likely contribute to the clinical effectiveness of such medications. It is not clear how much these effects relate to the measured inhibition of platelet aggregation in response to specific agonists. These effects are observable only with techniques that subject the growing thrombus to arterial flow and shear conditions. The effects of antithrombotic medications on thrombus stability and ways of assessing this are reviewed herein, and it is proposed that thrombus stability could become a new target for pharmacological intervention.Peer reviewedFinal Published versio
The use of satellite navigation systems and laser in road construction
Artykuł przedstawia zastosowanie GPS w budownictwie drogowym w celu kontroli i poprawy jakości wykonywanych robót drogowych. Nawigacja satelitarna jest stosowana w coraz większym zakresie w samochodach transportowych w celu śledzenia ruchu pojazdów (automonitoring), jak i w maszynach roboczych w budownictwie drogowym w celu zwiększenia efektywności i zmniejszenia kosztów robót, np. rozkładarki, spycharki, równiarki, koparki. Systemy GPS, w które wyposażane są maszyny drogowe, wykorzystywane są w kontroli grubości warstw nawierzchni oraz zagęszczenia podłoża lub warstw asfaltowych. Przedstawiono podstawy stosowanych systemów sterowania i kontroli pracy maszyn z wykorzystaniem nawigacji satelitarnej oraz przykłady wykorzystania w budowie dróg w USA i Polsce.Paper presents GPS applications in road building industry for control and quality improvement of road construction. Satellite navigation is applied in a wide range in transport tracks for route control (auto monitoring) as well as in equipment for road construction, eg. pavers, bulldozers, graders, excavators, to improve effectiveness and to reduce work costs. GPS systems in road equipment are applied for control of pavement layers thickness as well as compaction of subgrade or asphalt layers. Papers presents basics of the steering and machine control systems with use of satellite navigation as well as examples of applications in the USA and Poland
A stochastic context free grammar based framework for analysis of protein sequences
<p>Abstract</p> <p>Background</p> <p>In the last decade, there have been many applications of formal language theory in bioinformatics such as RNA structure prediction and detection of patterns in DNA. However, in the field of proteomics, the size of the protein alphabet and the complexity of relationship between amino acids have mainly limited the application of formal language theory to the production of grammars whose expressive power is not higher than stochastic regular grammars. However, these grammars, like other state of the art methods, cannot cover any higher-order dependencies such as nested and crossing relationships that are common in proteins. In order to overcome some of these limitations, we propose a Stochastic Context Free Grammar based framework for the analysis of protein sequences where grammars are induced using a genetic algorithm.</p> <p>Results</p> <p>This framework was implemented in a system aiming at the production of binding site descriptors. These descriptors not only allow detection of protein regions that are involved in these sites, but also provide insight in their structure. Grammars were induced using quantitative properties of amino acids to deal with the size of the protein alphabet. Moreover, we imposed some structural constraints on grammars to reduce the extent of the rule search space. Finally, grammars based on different properties were combined to convey as much information as possible. Evaluation was performed on sites of various sizes and complexity described either by PROSITE patterns, domain profiles or a set of patterns. Results show the produced binding site descriptors are human-readable and, hence, highlight biologically meaningful features. Moreover, they achieve good accuracy in both annotation and detection. In addition, findings suggest that, unlike current state-of-the-art methods, our system may be particularly suited to deal with patterns shared by non-homologous proteins.</p> <p>Conclusion</p> <p>A new Stochastic Context Free Grammar based framework has been introduced allowing the production of binding site descriptors for analysis of protein sequences. Experiments have shown that not only is this new approach valid, but produces human-readable descriptors for binding sites which have been beyond the capability of current machine learning techniques.</p
A Rare Case of Bilateral Upper Extremity Hypercalcinosis in Systemic Sclerosis Requiring Multiple Radical Debridements
Comparison of coenzyme Q10 or fish oil for prevention of intermittent hypoxia-induced oxidative injury in neonatal rat lungs
Abstract
Background
Neonatal intermittent hypoxia (IH) results in oxidative distress in preterm infants with immature antioxidant systems, contributing to lung injury. Coenzyme Q10 (CoQ10) and fish oil protect against oxidative injury. We tested the hypothesis that CoQ10 is more effective than fish oil for prevention of IH-induced lung injury in neonatal rats.
Methods
Newborn rats were exposed to two clinically relevant IH paradigms at birth (P0): (1) 50% O2 with brief hypoxia (12% O2); or (2) room air (RA) with brief hypoxia (12% O2), until P14 during which they were supplemented with daily oral CoQ10, fish oil, or olive oil from P0 to P14. Pups were studied at P14 or placed in RA until P21 with no further treatment. Lungs were assessed for histopathology and morphometry; biomarkers of oxidative stress and lipid peroxidation; and antioxidants.
Results
Of the two neonatal IH paradigms 21%/12% O2 IH resulted in the most severe outcomes, evidenced by histopathology and morphometry. CoQ10 was effective for preserving lung architecture and reduction of IH-induced oxidative stress biomarkers. In contrast, fish oil resulted in significant adverse outcomes including oversimplified alveoli, hemorrhage, reduced secondary crest formation and thickened septae. This was associated with elevated oxidants and antioxidants activities.
Conclusions
Data suggest that higher FiO2 may be needed between IH episodes to curtail the damaging effects of IH, and to provide the lungs with necessary respite. The negative outcomes with fish oil supplementation suggest oxidative stress-induced lipid peroxidation.
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Do elevated levels of interleukin-6 activated through PICSO intervention promote structural regeneration in heart failure patients?
Sex-specific platelet activation through protease-activated receptor-1 in patients undergoing cardiac catheterization
Atherosclerosis / Sex-specific platelet activation through protease-activated receptor-1 in patients undergoing cardiac catheterization
Background and aims
Protease-activated receptor (PAR)-1-mediated platelet activation may vary according to sex and clinical situation. In order to investigate sex-specific platelet activation through PAR-1, we assessed platelet response to thrombin receptor-activating peptide (TRAP) in 562 patients undergoing cardiac catheterization without (Group 1A) and with (Group 1B) acute coronary syndrome (ACS). Subsequently, we sought to confirm our findings in 287 patients undergoing elective (Group 2A) or acute (Group 2B) percutaneous coronary intervention.
Methods
TRAP-stimulated platelet surface expression of P-selectin and activated glycoprotein IIb/IIIa (GPIIb/IIIa) were measured by flow cytometry in Group 1. Light transmission aggregometry (LTA) and multiple electrode aggregometry (MEA) in response to TRAP were assessed in Group 2.
Results
In Group 1A, platelet activation in response to TRAP was significantly higher in women compared to men (P-selectin: 511 MFI [443–597 MFI] vs. 471 MFI [393–552 MFI]; GPIIb/IIIa: 84 MFI [58–119 MFI] vs. 70 MFI [47–103 MFI]; both p ≤ 0.002). In contrast, in Group 1B, TRAP-stimulated P-selectin and activated GPIIb/IIIa were similar in men and women (both p ≥ 0.3). Likewise, TRAP-stimulated platelet aggregation was significantly higher in female patients in Group 2A (LTA: 66% [54–76%] vs. 51% [41–65%]; MEA: 78 AU [66–107 AU] vs. 62 AU [52–88 AU]; both p ≤ 0.02), whereas men and women in Group 2 B had similar platelet aggregation (p = 0.5). The occurrence of ischemic endpoints did not differ significantly between men and women in Group 1A and Group 1B.
Conclusions
Platelet PAR-1 signaling is more pronounced in women than in men without ACS. In ACS, however, PAR-1-mediated platelet activation is similar in male and female patients
