Электрокардиостимуляция при острых отравлениях противоаритмическими препаратами у детей (клинический случай)

Severe poisoning with cardiotropic drugs in children,  accompanied  by pronounced rhythm disorders  and low cardiac output syndrome,  is quite rare, but sometimes they can end fatally.The objective was to demonstrate the successful use of electrocardiostimulation in acute propafenone  poisoning in a child of three years old.Materials and Methods. A retrospective analysis of the features of the course of severe propafenone poisoning in a three-year-old child who required pacing was carried out. Special attention was paid to the analysis of rhythm disorders  that  led to cardiac arrest  by the type of electrical  activity without a pulse, high efficiency of timely electrocardiostimulation in order to relieve bradyarrhythmia. Against the background of the therapy,  a stable recovery of the correct  sinus rhythm was achieved six hours after the connection of a temporary electrocardiostimulator.Conclusion. The presence  of persistent bradyarrhythmia-type rhythm disorders  in acute  poisoning with antiarrhythmic drugs in children  is an indication for the emergency use of electrocardiostimulation.Тяжелые отравления кардиотропными препаратами у детей, сопровождающиеся выраженными нарушениями ритма и синдромом малого сердечного выброса, встречаются достаточно редко, но при этом иногда могут заканчиваться фатально.Цель: продемонстрировать успешное применение электрокардиостимуляции при остром отравлении пропафеноном у ребенка трех лет.Материалы и методы. Проведен  ретроспективный анализ  особенностей  течения  тяжелого  отравления пропафеноном у ребенка  3 лет, потребовавшего  проведения  кардиостимуляции. Особое внимание уделено анализу нарушений  ритма, приведших  к остановке сердца по типу электрической активности без пульса, и эффективности своевременного проведения  электрокардиостимуляции для купирования брадиаритмии. На фоне проводимой терапии  достигнуто  стойкое восстановление правильного синусового  ритма спустя 6 часов от подключения  временного электрокардиостимулятора.Заключение. Наличие стойких нарушений  ритма по типу брадиаритмии при острых отравлениях противоаритмическими препаратами у детей является показанием  для экстренного применения электрокардиостимуляции

Interaction of a Ti–Cu Alloy with Carbon: Synthesis of Composites and Model Experiments

Titanium carbide (TiC), is the most thermodynamically stable compound in the Ti−C−Cu system, which makes it a suitable reinforcement phase for copper matrix composites. In this work, the interaction of a Ti−Cu alloy with different forms of carbon was investigated to trace the structural evolution leading to the formation of in-situ TiC−Cu composite structures. The reaction mixtures were prepared from Ti25Cu75 alloy ribbons and carbon black or nanodiamonds to test the possibilities of obtaining fine particles of TiC using ball milling and Spark Plasma Sintering (SPS). It was found that the behavior of the reaction mixtures during ball milling depends on the nature of the carbon source. Model experiments were conducted to observe the outcomes of the diffusion processes at the alloy/carbon interface. It was found that titanium atoms diffuse to the alloy/graphite interface and react with carbon forming a titanium carbide layer, but carbon does not diffuse into the alloy. The diffusion experiments as well as the synthesis by ball milling and SPS indicated that the distribution of TiC particles in the composite structures obtained via reactive solid-state processing of Ti25Cu75+C follows the distribution of carbon particles in the reaction mixtures. This justifies the use of carbon sources that have fine particles to prepare the reaction mixtures as well as efficient dispersion of the carbon component in the alloy−carbon mixture when the goal is to synthesize fine particles of TiC in the copper matrix

Ti-Al3_3Ti metal-intermetallic laminate (MIL) composite with a cubic titanium trialuminide stabilized with silver: Selection of fabrication regimes, structure, and properties

Ti-Al$_3$Ti metal-intermetallic laminate (MIL) composites are known as promising structural materials due to the unique combination of their specific properties. However, their application is still limited due to the extremely high brittleness of the Al3Ti phase. In this study, we attempt to address this issue by changing the D0$_{22}$ crystal structure of Al$_3$Ti to the more ductile L1$_2$ structure by alloying it with silver. To select the best fabrication regimes of Ti-Ti(Al$_{1−x}$Ag$_x$)$_3$ composites, in situ synchrotron X-ray diffraction analysis was performed to reveal the chemical reactions occurring upon heating the Ti-Al-Ag sample. The analysis showed that the highest amount of Ti(Al$_{1−x}$Ag$_x$)$_3$ phase with the L1$_2$ structure appears at 930 °C. This temperature was chosen for subsequent spark plasma sintering experiments. Scanning electron microscopy, energy dispersive X-ray analysis, and X-ray diffraction analysis revealed that the sintered sample consisted mainly of Ti, Ti(Al$_{1−x}$Ag$_x$)$_3$, and a minor fraction of the Ag-Al compound distributed in the central parts of the intermetallic layers and at the grain boundaries. Modification of the titanium trialuminide crystal structure positively affected the properties of the composite, providing a 60% increase in fracture toughness. The Ag-Al phase also contributed to toughening, causing an additional crack deflection effect