Venous Air Embolism and Complement-driven Thromboinflammation. In vitro human whole blood studies and in vivo porcine studies on the effect of air emboli on the complement system, cytokine network, and the hemostasis

Background: Air embolism may complicate many medical procedures and cause vascular occlusion, organ infarctions, or death. In vitro, air triggers the alternative complement pathway and activates platelets. Previous studies of air emboli were conducted in serum, plasma, or heparin anticoagulated whole blood, with ambient air present in tubes, precluding detailed examination of thromboinflammation. The role of complement in air-induced thromboinflammation has not previously been examined in vivo in minimally anticoagulated large animal model. Thus, this project aimed to examine the effect of avoiding ambient air during in vitro blood incubations and to elucidate the air-induced thromboinflammation both in vitro and in vivo. Methods: In vitro, lepirudin anticoagulated human whole blood from 16 donors was either incubated for 180 minutes with air emboli and inhibitors of complement C3 and C5, C5a receptor 1, and the toll-like receptor co-receptor cluster of differentiation 14, or without air. Blood was analyzed for complement activation products, cytokines, tissue factor, β-thromboglobulin, and prothrombin fragment 1+2. In vivo, air was infused through an ear vein in 29 pigs for 300 minutes. Hemostasis was monitored using rotational thromboelastometry and thrombin-antithrombin complex. Blood and lung tissue were analyzed for complement activation products and cytokines. Results: In vitro and in vivo, air emboli triggered a C3-driven thromboinflammation without correlating terminal pathway activation. In vitro, C3 inhibition, and to a lesser degree, C5 inhibition attenuated cytokine release, and C3 and C5 inhibition equally reduced coagulation, but neither reduced the platelet activation. Avoiding ambient air during in vitro incubations reduced complement activation. In vivo, air embolism resulted in leukocytosis, hemostasis, increased proinflammatory cytokines and complement activation product C3a, but not TCC in the lung tissue. Conclusion: Air embolism triggered a complement C3-driven thromboinflammation in vitro and in vivo. During in vitro blood incubations, avoiding ambient air attenuated and C3 inhibition reduced thromboinflammation

Forgetting as a consequence of retrieval: a meta-analytic review of retrieval-induced forgetting

Retrieving a subset of items can cause the forgetting of other items, a phenomenon referred to as retrieval-induced forgetting. According to some theorists, retrieval-induced forgetting is the consequence of an inhibitory mechanism that acts to reduce the accessibility of non-target items that interfere with the retrieval of target items. Other theorists argue that inhibition is unnecessary to account for retrieval-induced forgetting, contending instead that the phenomenon can be best explained by non-inhibitory mechanisms, such as strength-based competition or blocking. The current paper provides the first major meta-analysis of retrieval-induced forgetting, conducted with the primary purpose of quantitatively evaluating the multitude of findings that have been used to contrast these two theoretical viewpoints. The results largely supported inhibition accounts, but also provided some challenging evidence, with the nature of the results often varying as a function of how retrieval-induced forgetting was assessed. Implications for further research and theory development are discussed

Модель смешанного обучения в преподавании дисциплины "Методы получения чистых веществ"

Данная работа посвящена использованию модели смешанного обучения в преподавании дисциплины "Методы получения чистых веществ" на английском языке. Исследовались элементы смешанного обучения, стратегия организации образовательного процесса, план учебной деятельности. Подробно описаны виды учебной деятельности и подобраны формы организации процесса. Для каждого вида деятельности определены уровни таксономии Блума. Показаны преимущества модели смешанного обучения в преподавании лабораторных работ для студентов инженерной специальности

Controlling embryonic stem cell proliferation and pluripotency: the role of PI3K-and GSK-3- dependent signalling

Abstract ESCs (embryonic stem cells) are derived from the inner cell mass of pre-implantation embryos and are pluripotent, meaning they can differentiate into all of the cells that make up the adult organism. This property of pluripotency makes ESCs attractive as a model system for studying early development and for the generation of specific cell types for use in regenerative medicine and drug screening. In order to harness their potential, the molecular mechanisms regulating ESC pluripotency, proliferation and differentiation (i.e. cell fate) need to be understood so that pluripotency can be maintained during expansion, while differentiation to specific lineages can be induced accurately when required. The present review focuses on the potential roles that PI3K (phosphoinositide 3-kinase) and GSK-3 (glycogen synthase kinase 3)-dependent signalling play in the co-ordination and integration of mouse ESC pluripotency and proliferation and contrast this with our understanding of their functions in human ESCs. Control of ESC (embryonic stem cell) fate: an overview ESCs are derived from early pre-implantation embryos and, when cultured appropriately, can be maintained in a proliferative, self-renewing and pluripotent state almost indefinitely. Pluripotency is the ability to differentiate into all of the cells found in an adult organism, while self-renewal describes the generation of a daughter stem cell from its mother. In the case of ESCs, self-renewal occurs symmetrically, such that when an undifferentiated ESC divides and pluripotency is maintained, both its progeny will be undifferentiated Over the last 5-10 years, our understanding of the molecular components involved in maintaining pluripotency of mESCs (mouse ESCs) has increased dramatically, from a simple 'prelude' where STAT3 (signal transducer and activator of transcription 3) activation by LIF (leukaemia Key words: cell cycle, embryonic stem cell, glycogen synthase kinase 3 (GSK-3), phosphoinositide 3-kinase (PI3K), pluripotency, proliferation, self-renewal. Abbreviations used: CDK, cyclin-dependent kinase; ESC, embryonic stem cell; Esrrb, oestrogenrelated receptor β; GSK-3, glycogen synthase kinase-3; hESC, human ESC; LIF, leukaemia inhibitory factor; MEK, mitogen-activated protein kinase/extracellular-signal-regulated kinase kinase; mESC, mouse ESC; miRNA, microRNA; mTOR, mammalian target of rapamycin; PI3K, phosphoinositide 3-kinase; siRNA, short interfering RNA. 1 To whom correspondence should be addressed (email [email protected]). inhibitory factor) was all that seemed necessary, to a complex 'symphony' where extrinsic factors, intracellular signals, transcription factors, epigenetic regulators and miRNAs (microRNAs) have all been implicated The ESC cell cycle mESCs proliferate rapidly in culture and display unique cell-cycle kinetics, distinct from those of somatic cells, dividing approximately every 11-16 h and exhibiting a shortened G 1 -phase INK4a [13] and neither do mESCs arrest following DNA damag

Open chest and pericardium facilitate transpulmonary passage of venous air emboli

Background: Transpulmonary passage of air emboli can lead to fatal brain- and myocardial infarctions. We studied whether pigs with open chest and pericardium had a greater transpulmonary passage of venous air emboli than pigs with closed thorax. Methods: We allocated pigs with verified closed foramen ovale to venous air infusion with either open chest with sternotomy and opening of the pleura and pericardium (n = 8) or closed thorax (n = 16). All pigs received a five-hour intravenous infusion of ambient air, starting at 4-6 mL/kg/h and increased by 2 mL/kg/h each hour. We assessed transpulmonary air passage by transesophageal M-mode echocardiography and present the results as median with inter-quartile range (IQR). Results: Transpulmonary air passage occurred in all pigs with open chest and pericardium and in nine pigs with closed thorax (56%). Compared to pigs with closed thorax, pigs with open chest and pericardium had a shorter to air passage (10 minutes (5-16) vs. 120 minutes (44-212), P < .0001), a smaller volume of infused air at the time of transpulmonary passage (12 mL (10-23) vs.170 mL (107-494), P < .0001), shorter time to death (122 minutes (48-185) vs 263 minutes (248-300, P = .0005) and a smaller volume of infused air at the time of death (264 mL (53-466) vs 727 mL (564-968), P = .001). In pigs with open chest and, infused air and time to death correlated strongly (r = 0.95, P = .001). Conclusion: Open chest and pericardium facilitated the transpulmonary passage of intravenously infused air in pigs

Transfer of Learning Transformed

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/96651/1/j.1467-9922.2012.00740.x.pd

Iatrogenic air embolism: pathoanatomy, thromboinflammation, endotheliopathy, and therapies

Iatrogenic vascular air embolism is a relatively infrequent event but is associated with significant morbidity and mortality. These emboli can arise in many clinical settings such as neurosurgery, cardiac surgery, and liver transplantation, but more recently, endoscopy, hemodialysis, thoracentesis, tissue biopsy, angiography, and central and peripheral venous access and removal have overtaken surgery and trauma as significant causes of vascular air embolism. The true incidence may be greater since many of these air emboli are asymptomatic and frequently go undiagnosed or unreported. Due to the rarity of vascular air embolism and because of the many manifestations, diagnoses can be difficult and require immediate therapeutic intervention. An iatrogenic air embolism can result in both venous and arterial emboli whose anatomic locations dictate the clinical course. Most clinically significant iatrogenic air emboli are caused by arterial obstruction of small vessels because the pulmonary gas exchange filters the more frequent, smaller volume bubbles that gain access to the venous circulation. However, there is a subset of patients with venous air emboli caused by larger volumes of air who present with more protean manifestations. There have been significant gains in the understanding of the interactions of fluid dynamics, hemostasis, and inflammation caused by air emboli due to in vitro and in vivo studies on flow dynamics of bubbles in small vessels. Intensive research regarding the thromboinflammatory changes at the level of the endothelium has been described recently. The obstruction of vessels by air emboli causes immediate pathoanatomic and immunologic and thromboinflammatory responses at the level of the endothelium. In this review, we describe those immunologic and thromboinflammatory responses at the level of the endothelium as well as evaluate traditional and novel forms of therapy for this rare and often unrecognized clinical condition

Iatrogenic air embolism: pathoanatomy, thromboinflammation, endotheliopathy, and therapies

Iatrogenic vascular air embolism is a relatively infrequent event but is associated with significant morbidity and mortality. These emboli can arise in many clinical settings such as neurosurgery, cardiac surgery, and liver transplantation, but more recently, endoscopy, hemodialysis, thoracentesis, tissue biopsy, angiography, and central and peripheral venous access and removal have overtaken surgery and trauma as significant causes of vascular air embolism. The true incidence may be greater since many of these air emboli are asymptomatic and frequently go undiagnosed or unreported. Due to the rarity of vascular air embolism and because of the many manifestations, diagnoses can be difficult and require immediate therapeutic intervention. An iatrogenic air embolism can result in both venous and arterial emboli whose anatomic locations dictate the clinical course. Most clinically significant iatrogenic air emboli are caused by arterial obstruction of small vessels because the pulmonary gas exchange filters the more frequent, smaller volume bubbles that gain access to the venous circulation. However, there is a subset of patients with venous air emboli caused by larger volumes of air who present with more protean manifestations. There have been significant gains in the understanding of the interactions of fluid dynamics, hemostasis, and inflammation caused by air emboli due to in vitro and in vivo studies on flow dynamics of bubbles in small vessels. Intensive research regarding the thromboinflammatory changes at the level of the endothelium has been described recently. The obstruction of vessels by air emboli causes immediate pathoanatomic and immunologic and thromboinflammatory responses at the level of the endothelium. In this review, we describe those immunologic and thromboinflammatory responses at the level of the endothelium as well as evaluate traditional and novel forms of therapy for this rare and often unrecognized clinical condition

Radiation and breast cancer: a review of current evidence

This paper summarizes current knowledge on ionizing radiation-associated breast cancer in the context of established breast cancer risk factors, the radiation dose–response relationship, and modifiers of dose response, taking into account epidemiological studies and animal experiments. Available epidemiological data support a linear dose–response relationship down to doses as low as about 100 mSv. However, the magnitude of risk per unit dose depends strongly on when radiation exposure occurs: exposure before the age of 20 years carries the greatest risk. Other characteristics that may influence the magnitude of dose-specific risk include attained age (that is, age at observation for risk), age at first full-term birth, parity, and possibly a history of benign breast disease, exposure to radiation while pregnant, and genetic factors