Effect of 8-bromo-cyclic guanosine monophosphate (cGMP) on coronary artery constriction in isolated rabbit hearts

The vasodilator 8-bromo-guanosine 3′:5′-monophosphate (8-bromo-cGMP) effectively counteracts vaso-pressin-induced coronary artery constriction in a supported perfused working rabbit heart. In this preparation, the coronary arteries remain in contact with the beating heart. The obtuse marginal artery and portions of the left anterior descending coronary artery were deprived of endothelium. Perfusion was carried out with Krebs-Henseleit solution, oxygenated with a disposable infant oxygenator. The internal diameter of large coronary arteries was determined by color arteriography (injection of patent blue dye and gated photography). The effect of vasopressin with and without the addition of 8-bromo-cGMP on cardiac performance (cardiac output, left ventricular systolic pressure, left ventricular end-diastolic pressure, maximal rate of rise in left ventricular pressure [dP/dtmax], mean aortic pressure) and large coronary vessel and total coronary vascular resistance was determined in nine experiments. In addition, changes in coronary sinus partial pressure of carbon dioxide (Pco2) and pH were observed.Vasopressin alone caused a significant decline in coronary flow, myocardial oxygen consumption and coronary sinus pH. Cardiac performance declined, probably because of myocardial ischemia. Large coronary vessel and total coronary vascular resistance rose. The vasodilator 8-bromo-cGMP strongly inhibited the vasoconstrictor action of vasopressin, counteracted the increase in large and total coronary vascular resistance, prevented the fall in myocardial oxygen consumption and eliminated changes in pH or Pco2of coronary sinus effluent. Because of the elimination of myocardial ischemia by 8-bromo-cGMP, cardiac performance was normalized. The presence of 8-bromo-cGMP significantly shifted the dose-response relation between vasopressin and coronary flow and between vasopressin and total coronary resistance to the right, and caused an increase in the units for the concentration required to obtain 50% of the maximal effect. The results indicate that 8-bromo-cGMP has the potential to become a useful agent in counteracting coronary artery constriction in vivo, particularly in those instances in which the coronary endothelium has been damaged

Разработка коллекции дверной фурнитуры в технологиях металлообработки

Выпускная квалификационная работа содержит пояснительную записку, содержащую 85 страниц, включает (…) Объектами проектирования являются элементы коллекций, выполненных в трех разных стилях. Цель работы – разработка коллекций дверной фурнитуры в технологиях металлообработки. В процессе выпускной квалификационной работы было разработано три колелекции дверной фурнитуры, каждая из которых включает в себя три элемента. Выпускная квалификационная работа выполнена в текстовом редакторе Microsoft Word 2013. При создании электронных моделей использовался программный продукт SolidWorks2015 и ArtCAM 2008. Художественная часть создавалась с помощью бумаги и сангины. В результате исследования создан элемент коллекции в технологиях металлообработки.Final qualifying work contains an explanatory note containing 85 pages, includes (...) The objects are the elements of the design collections, made in three different styles. The purpose of work - development of collections of door hardware in metalworking technologies. During the final qualifying work three kolelektsii door fittings have been developed, each of which includes three elements. Final qualifying work carried out in Microsoft Word 2013. When you create a text editor, electronic models used by software SolidWorks2015 and ArtCAM 2008. Artistic part was created with the help of paper and sanguine. The study created a collection item in metalworking technologies

MR fluoroscopy in vascular and cardiac interventions (review)

Vascular and cardiac disease remains a leading cause of morbidity and mortality in developed and emerging countries. Vascular and cardiac interventions require extensive fluoroscopic guidance to navigate endovascular catheters. X-ray fluoroscopy is considered the current modality for real time imaging. It provides excellent spatial and temporal resolution, but is limited by exposure of patients and staff to ionizing radiation, poor soft tissue characterization and lack of quantitative physiologic information. MR fluoroscopy has been introduced with substantial progress during the last decade. Clinical and experimental studies performed under MR fluoroscopy have indicated the suitability of this modality for: delivery of ASD closure, aortic valves, and endovascular stents (aortic, carotid, iliac, renal arteries, inferior vena cava). It aids in performing ablation, creation of hepatic shunts and local delivery of therapies. Development of more MR compatible equipment and devices will widen the applications of MR-guided procedures. At post-intervention, MR imaging aids in assessing the efficacy of therapies, success of interventions. It also provides information on vascular flow and cardiac morphology, function, perfusion and viability. MR fluoroscopy has the potential to form the basis for minimally invasive image–guided surgeries that offer improved patient management and cost effectiveness