bluuebunny/crossref_metadata_2025 huggingface dataset:
Chest pain and chest pain units
Authors: Durand Eric , Chaib Aures , Danchin Nicolas
Published: April 2015

Patients presenting at the emergency department with acute chest pain and suspected to represent an acute coronary syndrome were classically admitted as routine to the cardiology department, resulting in expensive and time-consuming evaluations. However, 2-5% of patients with acute coronary syndromes were discharged home inappropriately, resulting in increased mortality. To address the inability to exclude the diagnosis of acute coronary syndrome, chest pain units were developed, particularly in the United States. These provided an environment where serial electrocardiograms, cardiac biomarkers, and provocative testing could be performed to rule out an acute coronary syndrome. Eligible candidates included the majority of patients with non-diagnostic electrocardiograms and normal troponin measurements. The results have been impressive; chest pain units have markedly reduced adverse events, while simultaneously increasing the rate of safe discharge by 36%. Despite evidence to suggest that care in chest pain units is more effective for such patients, the percentage of emergency or cardiology departments setting up chest pain units remains very low in Europe.
Computed tomography angiography and other applications of computed tomography
Authors: de Graaf Michiel A , Scholte Arthur JHA , Kroft Lucia , Bax Jeroen J
Published: April 2015

Patients presenting with acute chest pain constitute a common and important diagnostic challenge. This has increased interest in using computed tomography for non-invasive visualization of coronary artery disease in patients presenting with acute chest pain to the emergency department; particularly the subset of patients who are suspected of having an acute coronary syndrome, but without typical electrocardiographic changes and with normal troponin levels at presentation. As a result of rapid developments in coronary computed tomography angiography technology, high diagnostic accuracies for excluding coronary artery disease can be obtained. It has been shown that these patients can be discharged safely. The accuracy for detecting a significant coronary artery stenosis is also high, but the presence of coronary artery atherosclerosis or stenosis does not imply necessarily that the cause of the chest pain is related to coronary artery disease. Moreover, the non-invasive detection of coronary artery disease by computed tomography has been shown to be related with an increased use of subsequent invasive coronary angiography and revascularization, and further studies are needed to define which patients benefit from invasive evaluation following coronary computed tomography angiography. Conversely, the implementation of coronary computed tomography angiography can significantly reduce the length of hospital stay, with a significant cost reduction. Additionally, computed tomography is an excellent modality in patients whose symptoms suggest other causes of acute chest pain such as aortic aneurysm, aortic dissection, or pulmonary embolism. Furthermore, the acquisition of the coronary arteries, thoracic aorta, and pulmonary arteries in a single computed tomography examination is feasible, allowing ‘triple rule-out’ (exclusion of aortic dissection, pulmonary embolism, and coronary artery disease). Finally, other applications, such as the evaluation of coronary artery plaque composition, myocardial function and perfusion, or fractional flow reserve, are currently being developed and may also become valuable in the setting of acute chest pain in the future.
Non-invasive ventilation
Authors: Masip Josep , Planas Kenneth , Mas Arantxa
Published: April 2015

During the last 25 years, the use of non-invasive ventilation has grown substantially. Non-invasive ventilation refers to the delivery of positive pressure to the lungs without endotracheal intubation and plays a significant role in the treatment of patients with acute respiratory failure and in the domiciliary management of some chronic respiratory and sleep disorders. In the intensive and acute care setting, the primary aim of non-invasive ventilation is to avoid intubation, and it is mainly used in patients with chronic obstructive pulmonary disease exacerbations, acute cardiogenic pulmonary oedema, or in the context of weaning, situations in which a reduction in mortality has been demonstrated. The principal techniques are continuous positive airway pressure and bilevel pressure support ventilation. Whereas non-invasive pressure support ventilation requires a ventilator, continuous positive airway pressure is a simpler technique that can be easily used in non-equipped areas such as the pre-hospital setting. The success of non-invasive ventilation is related to the adequate timing and selection of patients, as well as the appropriate use of interfaces, the synchrony of patient-ventilator, and the fine-tuning of the ventilator.
Portable (short-term) mechanical circulatory support
Authors: Price Susanna , Vranckx Pascal
Published: April 2015

Mechanical circulatory support can be used to resuscitate patients, as a stabilizing measure for angiography and prompt revascularization, or to buy time until more definite measures can be taken. In addition, there is experimental evidence that ventricular unloading of the left ventricle can significantly reduce the infarct size. Different systems for mechanical circulatory support are available to the medical community. Treatment options for mechanical circulatory support must be tailored to each patient in order to maximize the potential benefits and minimize the risk of detrimental effects. Intra-aortic balloon pumping is still the most widely used mechanical circulatory support therapy. The relative ease and speed with which this device can be applied to patients with a rapidly deteriorating haemodynamic picture have led to its widespread use as a first-line intervention among critically unstable patients. Where intra-aortic balloon pumping is inadequate, an immediate triage to a more advanced percutaneous (short-term) mechanical circulatory support may be warranted. Despite their extensive use, the utility of mechanical circulatory support devices in acute heart failure syndromes and cardiogenic shock remains uncertain. This chapter concentrates on the application of mechanical circulatory support relevant to the interventional cardiologist and cardiac intensive care physician.
Biomarkers in acute coronary syndromes
Authors: Giannitsis Evangelos , Katus Hugo A
Published: April 2015

Biomarker testing in the evaluation of a patient with acute chest pain is best established for cardiac troponins that allow the diagnosis of myocardial infarction, risk estimation of short- and long-term risk of death and myocardial infarction, and guidance of pharmacological therapy, as well as the need and timing of invasive strategy. Newer, more sensitive troponin assays have become commercially available and have the capability to detect myocardial infarction earlier and more sensitively than standard assays, but they are hampered by a lack of clinical specificity, i.e. the ability to discriminate myocardial ischaemia from myocardial necrosis not related to ischaemia such as myocarditis, pulmonary embolism, or decompensated heart failure. Strategies to improve clinical specificity (including strict adherence to the universal myocardial infarction definition and the need for serial troponin measurements to detect an acute rise and/or fall of cardiac troponin) will improve the interpretation of the increasing number of positive results. Other biomarkers of inflammation, activated coagulation/fibrinolysis, and increased ventricular stress mirror different aspects of the underlying disease activity and may help to improve our understanding of the pathophysiological mechanisms of acute coronary syndromes. Among the flood of new biomarkers, there are several novel promising biomarkers, such as copeptin that allows an earlier rule-out of myocardial infarction in combination with cardiac troponin, whereas MR-proANP and MR-proADM appear to allow a refinement of cardiovascular risk. GDF-15 might help to identify candidates for an early invasive vs conservative strategy. A multi-marker approach to biomarkers becomes more and more attractive, as increasing evidence suggests that a combination of several biomarkers may help to predict individual risk and treatment benefits, particularly among troponin-negative subjects. Future goals include the acceleration of rule-in and rule-out of patients with suspected acute coronary syndrome, in order to shorten lengths of stay in the emergency department, and to optimize patient management and the use of health care resources. New algorithms using high-sensitivity cardiac troponin assays at low cut-offs alone, or in combination with additional biomarkers, allow to establish accelerated rule-out algorithms within 1 or 2 hours.
Systems of care for patients with acute ST elevation myocardial infarction (STEMI networks)
Authors: Huber Kurt , Quinn Tom
Published: April 2015

Although primary percutaneous coronary intervention is the preferred strategy for patients with ST elevation myocardial infarction, offering a fast access to this procedure often remains difficult, because of local resources and capabilities and a lack of cooperation and organization. Accordingly, for most countries worldwide, primary percutaneous coronary intervention can be provided for only part of the population. Moreover, not all patients referred for primary percutaneous coronary intervention receive an optimal mechanical reperfusion within the recommended time intervals with the procedure performed in an experienced centre by an experienced team. Intravenous thrombolytic therapy, preferably administered pre-hospital and as part of a pharmacoinvasive strategy, offers a reasonable therapeutic option in selected cases. Network organization is central to offering fast and optimal reperfusion treatment in the individual case. It has been shown repeatedly that an early recognition of ST elevation myocardial infarction, as well as minimizing time delays, is important for the achievement of optimal clinical results. These findings should encourage the building up of regional networks, according to specific local constraints, and the monitoring of their effectiveness by ongoing registries. Financial, regulatory, and political barriers can be resolved, and a prompt guideline-recommended care becomes feasible and affordable if stakeholders and participants agree and cooperate.
Fibrinolytic, antithrombotic, and antiplatelet drugs in acute coronary syndromes
Authors: Sinnaeve Peter , Van de Werf Frans
Published: April 2015

Antithrombotic therapy is a major cornerstone in the treatment for acute coronary syndromes, as thrombus formation upon a plaque rupture or an erosion plays a pivotal role in non-ST-segment elevation as well as ST-segment elevation acute coronary syndromes. Both acute and long-term oral antiplatelet therapies, targeting specific platelet activation pathways, have demonstrated significant short- and long-term benefits. The use of anticoagulants is currently largely confined to the acute setting, except in patients with a clear indication for long-term treatment, including atrial fibrillation or the presence of intraventricular thrombi. Despite the benefit of primary percutaneous coronary intervention in ST-segment elevation myocardial infarction, fibrinolysis continues to play an important role throughout the world as well. In this chapter, the fibrinolytic, antiplatelet, and anticoagulant agents used in the management of acute coronary syndrome patients are discussed.
Non-ST-segment elevation acute coronary syndromes
Authors: Bueno Héctor , Barrabés José A
Published: April 2015

Non-ST-segment elevation acute coronary syndromes are life-threatening disorders, usually caused by acute coronary thrombosis and subsequent myocardial ischaemia, presenting without persistent ST-segment elevation in the initial electrocardiogram. According to the occurrence of myocardial necrosis, non-ST-segment elevation acute coronary syndromes are divided into non-ST-segment myocardial infarction or unstable angina. The management of non-ST-segment elevation acute coronary syndromes requires an early diagnosis and risk stratification, urgent hospitalization, monitoring, and medical treatment, including antithrombotic therapy with dual antiplatelet therapy (aspirin plus one P2Y12 inhibitor) and parenteral anticoagulation, anti-ischaemic treatment, and preventative therapies. After the initial medical therapy is established, an invasive strategy, consisting of coronary angiography with coronary revascularization (either percutaneous coronary intervention or coronary bypass graft surgery), as appropriate, should be decided. The timing of the invasive strategy should be adjusted, according to the patient’s risk. Given the high event rate of patients with non-ST-segment elevation acute coronary syndromes after hospital discharge, an aggressive long-term preventative therapy should be put in place to improve prognosis.
Percutaneous coronary interventions in acute coronary syndromes
Authors: Kočka Viktor , Kristensen Steen Dalby , Wijns William , Toušek Petr , Widimský Petr
Published: April 2015

Three different guidelines of the European Society of Cardiology cover the field of percutaneous coronary interventions. Their main recommendations are the following:All patients with an ST-segment elevation myocardial infarction should undergo immediate coronary angiography and percutaneous coronary intervention as soon as possible after the first medical contact. Thrombolysis can be used as an alternative reperfusion therapy if the time delay to primary percutaneous coronary intervention is more than 2 hoursPatients with very high-risk non-ST-segment elevation acute coronary syndromes (recurrent or ongoing chest pain, profound or dynamic electrocardiogram changes, major arrhythmias, or haemodynamic instability) should undergo urgent coronary angiography within less than 2 hours after the initial hospital admissionAll moderate- to high-risk (GRACE score >140 or at least one primary high-risk criterion) non-ST-segment elevation acute coronary syndromes patients should undergo coronary angiography before discharge; the ideal timing is within 24 hours after admission for high-risk groups, and within 72 hours for moderate-risk groupsOther patients with recurrent symptoms or at least one high-risk criterion should undergo coronary angiography within 72 hours of first presentationLow-risk non-ST-segment elevation acute coronary syndromes may be treated conservatively, and the indication for an invasive evaluation can be done, based on the evidence of ischaemia during exercise stress testingStents should be used during all percutaneous coronary intervention procedures, whenever technically feasible. Second-generation drug-eluting stents do not increase stent thrombosis and can be safely used in the ST-segment elevation myocardial infarction and non-ST-segment elevation acute coronary syndrome settingsTriple pharmacotherapy, consisting of aspirin, thienopyridine antiplatelet agent, and anticoagulation with heparin or bivalirudin, should be used in all percutaneous coronary intervention procedures, with glycoprotein IIb/IIIa inhibitors added in patients with a high thrombus burden and low bleeding risk
Acute heart failure: heart failure surgery and transplantation
Authors: Visouli Aikaterini N , Pitsis Antonis A
Published: April 2015

Cardiac surgery should be considered in all cases of acute heart failure that is attributed to surgically correctable causes. Surgical revascularization, repair of mechanical complications of myocardial infarction, valve repair or replacement, mechanical circulatory support, and heart transplantation represent the main surgical interventions that may be offered in the setting of acute (de novo or decompensated chronic) heart failure. Percutaneous aortic valve replacement should also be considered for patients who are deemed inoperable.
Acute valve disease and endocarditis
Authors: Ducrocq Gregory , Thuny Franck , Iung Bernard , Vahanian Alec
Published: April 2015

The management of patients with acute valve disease is now a rare, but challenging, event, as valvular patients are often elderly with severe comorbidities. Furthermore, a proportion of previously operated patients present with acute valve dysfunction. The aim, in this situation, is to establish a rapid diagnosis, based on clinical examination and echocardiography, followed by early intervention. The primary treatment remains surgical valve replacement. However, a more conservative surgical approach is under development, and, more recently, percutaneous interventional techniques have been introduced. In the future, every effort should be made to avoid performing interventions in an acute situation, as it is always at high risk.
Cardiac complications in trauma
Authors: Demetriades Demetrios , Kobayashi Leslie , Lam Lydia
Published: April 2015

Post-traumatic cardiac complications may occur after penetrating or blunt injuries to the heart or may follow severe extracardiac injuries. The majority of victims with penetrating injuries to the heart die at the scene and do not reach hospital care. For those patients who reach hospital care, an immediate operation, sometimes in the emergency room, cardiac injury repair, and cardiopulmonary resuscitation provide the only possibility of survival. Many patients develop perioperative cardiac complications such as acute cardiac failure, cardiac arrhythmias, coronary air embolism, and myocardial infarction. Some survivors develop post-operative functional abnormalities or anatomical defects, which may not manifest during the early post-operative period. It is essential that all survivors undergo detailed early and late cardiac evaluations. Blunt cardiac trauma encompasses a wide spectrum of injuries that includes asymptomatic myocardial contusion, arrhythmias, or cardiogenic shock to full-thickness cardiac rupture and death. Clinical examination, electrocardiograms, troponin measurements, and echocardiography are the cornerstone of diagnosis and monitoring of these patients. Lastly, some serious extracardiac traumatic conditions, such as traumatic pneumonectomy and severe traumatic brain injury, may result in cardiac complications. This may include tachyarrhythmias, cardiogenic shock, electrocardiographic changes, troponin elevations, heart failure, and cardiac arrest.
Acute kidney injury
Authors: Gevaert Sofie A , Hoste Eric , Kellum John A
Published: April 2015

Acute kidney injury is a serious condition, occurring in up to two-thirds of intensive care unit patients, and 8.8-55% of patients with acute cardiac conditions. Renal replacement therapy is used in about 5-10% of intensive care unit patients. The term cardiorenal syndrome refers to combined heart and kidney failure; three types of acute cardiorenal syndrome have been described: acute cardiorenal syndrome or cardiorenal syndrome type 1, acute renocardiac syndrome or cardiorenal syndrome type 3, and acute cardiorenal syndrome type 5 (cardiac and renal injury secondary to a third entity such as sepsis). Acute kidney injury replaced the previously used term ‘acute renal failure’ and comprises the entire spectrum of the disease, from small changes in function to the requirement of renal replacement therapy. Not only failure, but also minor and less severe decreases, in kidney function are of clinical significance both in the short and long-term. The most recent definition for acute kidney injury is proposed by the Kidney Disease: Improving Global Outcomes clinical practice guidelines workgroup. This definition is a modification of the RIFLE and AKIN definitions and staging criteria, and it stages patients according to changes in the urine output and serum creatinine (see Tables 68.1 and 68.2). Acute kidney injury is a heterogeneous syndrome with different and multiple aetiologies, often with several insults occurring in the same individual. The underlying processes include nephrotoxicity, and neurohormonal, haemodynamic, autoimmune, and inflammatory abnormalities. The most frequent cause for acute kidney injury in intensive cardiac care patients are low cardiac output with an impaired kidney perfusion (cardiogenic shock) and/or a marked increase in venous pressure (acute decompensated heart failure). Predictors for acute kidney injury in these patients include: baseline renal dysfunction, diabetes, anaemia, and hypertension, as well as the administration of high doses of diuretics. In the intensive cardiac care unit, attention must be paid to the prevention of acute kidney injury: monitoring of high-risk patients, prompt resuscitation, maintenance of an adequate mean arterial pressure, cardiac output, and intravascular volume (avoidance of both fluid overload and hypovolaemia), as well as the avoidance or protection against nephrotoxic agents. The treatment of acute kidney injury focuses on the treatment of the underlying aetiology, supportive care, and avoiding further injury from nephrotoxic agents. More specific therapies have not yet demonstrated efficacy. Renal replacement therapy is indicated in life-threatening changes in fluid, electrolyte, and acid-base balance, but there are also arguments for more early initiation.
Acute cognitive disorders: recognition and management of delirium in the cardiovascular intensive care unit
Authors: Giuseffi Jennifer , McPherson John , Wagner Chad , Ely E Wesley
Published: April 2015

Delirium is the most common acute cognitive disorder seen in critically ill patients in the cardiovascular intensive care unit. It is defined as a disturbance of consciousness and cognition that develops suddenly and fluctuates over time. Delirious patients can become hyperactive, hypoactive, or both. The occurrence of delirium during hospitalization is associated with increased in-hospital and long-term morbidity and mortality. The cause of delirium is multifactorial and may include imbalances in neurotransmitters, inflammatory mediators, metabolic disturbances, impaired sleep, and the use of sedatives and analgesics. Patients with advanced age, dementia, chronic illness, extensive vascular disease, and low cardiac output are at particular risk of developing delirium. Specialized bedside assessment tools are now available to rapidly diagnose delirium, even in mechanically ventilated patients. Increased awareness of delirium risk factors, in addition to non-pharmacological and pharmacological treatments for delirium, can be effective in reducing the incidence of delirium in cardiac patients and in minimizing adverse outcomes, once delirium occurs.
Perioperative management of the high-risk surgical patient: cardiac surgery
Authors: Ranucci Marco , Castelvecchio Serenella , Ballotta Andrea
Published: April 2015

During the last decade, as a result of continually improving surgical strategy and the technology which supports it (e.g. anaesthesia), cardiac surgery is offered to patients with advanced age and those with increasingly complex co-existing conditions that were previously considered to be contraindications. In addition, an increasing number of patients have previously undergone angioplasty, thereby delaying their initial coronary artery bypass graft surgery to a more advanced age. In general, candidates for cardiac surgery may now be not only older than in the past, but also more likely to have health problems such as hypertension and diabetes. Risk stratification may help to identify ‘the’ high-risk patient: ‘pre-warned is pre-armed’. In high-risk cardiac surgery patients, the surgical treatment options and perioperative care must be tailored to each patient, in order to optimize the benefits and minimize the risk of detrimental effects. The preoperative anticoagulation practice is an important aspect, balancing the risk between ischaemic and bleeding complications. New antiplatelet agents and oral anticoagulants have been recently delivered, and their role in patients scheduled for heart surgery is an additional important issue.
A dynamical model of plasma turbulence in the solar wind
Authors: Howes G. G.
Published: April 2015

A dynamical approach, rather than the usual statistical approach, is taken to explore the physical mechanisms underlying the nonlinear transfer of energy, the damping of the turbulent fluctuations, and the development of coherent structures in kinetic plasma turbulence. It is argued that the linear and nonlinear dynamics of Alfvén waves are responsible, at a very fundamental level, for some of the key qualitative features of plasma turbulence that distinguish it from hydrodynamic turbulence, including the anisotropic cascade of energy and the development of current sheets at small scales. The first dynamical model of kinetic turbulence in the weakly collisional solar wind plasma that combines self-consistently the physics of Alfvén waves with the development of small-scale current sheets is presented and its physical implications are discussed. This model leads to a simplified perspective on the nature of turbulence in a weakly collisional plasma: the nonlinear interactions responsible for the turbulent cascade of energy and the formation of current sheets are essentially fluid in nature, while the collisionless damping of the turbulent fluctuations and the energy injection by kinetic instabilities are essentially kinetic in nature.
The role of turbulence in coronal heating and solar wind expansion
Authors: Cranmer Steven R. , Asgari-Targhi Mahboubeh , Miralles Mari Paz , Raymond John C. , Strachan Leonard , Tian Hui , Woolsey Lauren N.
Published: April 2015

Plasma in the Sun's hot corona expands into the heliosphere as a supersonic and highly magnetized solar wind. This paper provides an overview of our current understanding of how the corona is heated and how the solar wind is accelerated. Recent models of magnetohydrodynamic turbulence have progressed to the point of successfully predicting many observed properties of this complex, multi-scale system. However, it is not clear whether the heating in open-field regions comes mainly from the dissipation of turbulent fluctuations that are launched from the solar surface, or whether the chaotic ‘magnetic carpet’ in the low corona energizes the system via magnetic reconnection. To help pin down the physics, we also review some key observational results from ultraviolet spectroscopy of the collisionless outer corona.
Short-wavelength plasma turbulence and temperature anisotropy instabilities: recent computational progress
Authors: Gary S. Peter
Published: April 2015

Plasma turbulence consists of an ensemble of enhanced, broadband electromagnetic fluctuations, typically driven by multi-wave interactions which transfer energy in wavevector space via non- linear cascade processes. Temperature anisotropy instabilities in collisionless plasmas are driven by quasi-linear wave–particle interactions which transfer particle kinetic energy to field fluctuation energy; the resulting enhanced fluctuations are typically narrowband in wavevector magnitude and direction. Whatever their sources, short-wavelength fluctuations are those at which charged particle kinetic, that is, velocity-space, properties are important; these are generally wavelengths of the order of or shorter than the ion inertial length or the thermal ion gyroradius. The purpose of this review is to summarize and interpret recent computational results concerning short-wavelength plasma turbulence, short-wavelength temperature anisotropy instabilities and relationships between the two phenomena.
Anisotropy in solar wind plasma turbulence
Authors: Oughton S. , Matthaeus W. H. , Wan M. , Osman K. T.
Published: April 2015

A review of spectral anisotropy and variance anisotropy for solar wind fluctuations is given, with the discussion covering inertial range and dissipation range scales. For the inertial range, theory, simulations and observations are more or less in accord, in that fluctuation energy is found to be primarily in modes with quasi-perpendicular wavevectors (relative to a suitably defined mean magnetic field), and also that most of the fluctuation energy is in the vector components transverse to the mean field. Energy transfer in the parallel direction and the energy levels in the parallel components are both relatively weak. In the dissipation range, observations indicate that variance anisotropy tends to decrease towards isotropic levels as the electron gyroradius is approached; spectral anisotropy results are mixed. Evidence for and against wave interpretations and turbulence interpretations of these features will be discussed. We also present new simulation results concerning evolution of variance anisotropy for different classes of initial conditions, each with typical background solar wind parameters.
Oxygen-sensing PHDs regulate bone homeostasis through the modulation of osteoprotegerin
Authors: Wu Colleen , Rankin Erinn B. , Castellini Laura , Fernandez-Alcudia Javier , LaGory Edward L. , Andersen Rebecca , Rhodes Steven D. , Wilson Tremika L.S. , Mohammad Khalid S. , Castillo Alesha B. , Guise Theresa A. , Schipani Ernestina , Giaccia Amato J.
Published: April 2015

The bone microenvironment is composed of niches that house cells across variable oxygen tensions. However, the contribution of oxygen gradients in regulating bone and blood homeostasis remains unknown. Here, we generated mice with either single or combined genetic inactivation of the critical oxygen-sensing prolyl hydroxylase (PHD) enzymes (PHD1–3) in osteoprogenitors. Hypoxia-inducible factor (HIF) activation associated with Phd2 and Phd3 inactivation drove bone accumulation by modulating osteoblastic/osteoclastic cross-talk through the direct regulation of osteoprotegerin (OPG). In contrast, combined inactivation of Phd1, Phd2, and Phd3 resulted in extreme HIF signaling, leading to polycythemia and excessive bone accumulation by overstimulating angiogenic–osteogenic coupling. We also demonstrate that genetic ablation of Phd2 and Phd3 was sufficient to protect ovariectomized mice against bone loss without disrupting hematopoietic homeostasis. Importantly, we identify OPG as a HIF target gene capable of directing osteoblast-mediated osteoclastogenesis to regulate bone homeostasis. Here, we show that coordinated activation of specific PHD isoforms fine-tunes the osteoblastic response to hypoxia, thereby directing two important aspects of bone physiology: cross-talk between osteoblasts and osteoclasts and angiogenic–osteogenic coupling.
A novel crystal-analyzer phase retrieval algorithm and its noise property
Authors: Bao Yuan , Wang Yan , Li Panyun , Wu Zhao , Shao Qigang , Gao Kun , Wang Zhili , Ju Zaiqiang , Zhang Kai , Yuan Qingxi , Huang Wanxia , Zhu Peiping , Wu Ziyu
Published: April 2015

A description of the rocking curve in diffraction enhanced imaging (DEI) is presented in terms of the angular signal response function and a simple multi-information retrieval algorithm based on the cosine function fitting. A comprehensive analysis of noise properties of DEI is also given considering the noise transfer characteristic of the X-ray source. The validation has been performed with synchrotron radiation experimental data and Monte Carlo simulations based on theGeant4toolkit combined with the refractive process of X-rays, which show good agreement with each other. Moreover, results indicate that the signal-to-noise ratios of the refraction and scattering images are about one order of magnitude better than that of the absorption image at the edges of low-Zsamples. The noise penalty is drastically reduced with the increasing photon flux and visibility. Finally, this work demonstrates that the analytical method can build an interesting connection between DEI and GDPCI (grating-based differential phase contrast imaging) and is widely suitable for a variety of measurement noise in the angular signal response imaging prototype. The analysis significantly contributes to the understanding of noise characteristics of DEI images and may allow improvements to the signal-to-noise ratio in biomedical and material science imaging.
Factors contributing to elder abuse in Ethiopia
Authors: Chane Samson , Adamek Margaret E.
Published: April 2015

Purpose

– The purpose of this paper is to increase understanding of elder abuse in Ethiopia by considering the perspectives of abused elders.

Design/methodology/approach

– A phenomenological study was conducted to investigate the lived experience of 15 elders (six men, nine women) in Ethiopia who experienced domestic abuse. Data were collected using unstructured interviews and were analyzed using interpretive phenomenological analysis. The results described here focus on Ethiopian elders’ perceptions of factors contributing to abuse.

Findings

– Themes identified in elders’ statements about the factors contributing to elder abuse included: declining respect for elders, conflicts of interest, poor health, mutual dependency and other economic issues, and loss of support providers. Abject poverty was evident as an underlying influence contributing to abuse. One elder stated, “Life is meaningless without food and without a caregiver. I am ready to welcome death.”

Research limitations/implications

– Documentation of elder abuse is needed to bring recognition to abuse as a problem deserving public attention and response.

Practical implications

– Given the apparent influence of poverty-related factors on the occurrence of elder abuse among the study's participants, policy initiatives are needed to enhance the economic well-being of older adults in Ethiopia.

Originality/value

– Since elder abuse is generally not viewed as a societal problem in Ethiopia, there have been very few studies documenting its existence. Research on elder abuse in Ethiopia and other developing nations can help to bring the issue to the attention of communities and authorities.
Rocket launcher: A novel reduction technique for posterior hip dislocations and review of current literature
Authors: Dan Michael , Phillips Alfred , Simonian Marcus , Flannagan Scott
Published: April 2015

Objective

We provide a review of literature on reduction techniques for posterior hip dislocations and present our experience with a novel technique for the reduction of acute posterior hip dislocations in the ED, ‘the rocket launcher’ technique.

Methods

We present our results with six patients with prosthetic posterior hip dislocation treated in our rural ED. We recorded patient demographics. The technique involves placing the patient's knee over the shoulder, and holding the lower leg like a ‘Rocket Launcher’ allow the physician's shoulder to work as a fulcrum, in an ergonomically friendly manner for the reducer. We used Fisher's t‐test for cohort analysis between reduction techniques.

Results

Of our patients, the mean age was 74 years (range 66 to 85 years). We had a 83% success rate. The one patient who the ‘rocket launcher’ failed in, was a hemi‐arthroplasty patient who also failed all other closed techniques and needed open reduction. When compared with Allis (62% success rate), Whistler (60% success rate) and Captain Morgan (92% success rate) techniques, there was no statistically significant difference in the successfulness of the reduction techniques. There were no neurovascular or periprosthetic complications.

Conclusion

We have described a reduction technique for posterior hip dislocations. Placing the patient's knee over the shoulder, and holding the lower leg like a ‘Rocket Launcher’ allow the physician's shoulder to work as a fulcrum, thus mechanically and ergonomically superior to standard techniques.
Identification of the Mamestra configurata (Lepidoptera: Noctuidae) peritrophic matrix proteins and enzymes involved in peritrophic matrix chitin metabolism
Authors: Toprak Umut , Erlandson Martin , Baldwin Doug , Karcz Steve , Wan Lianglu , Coutu Cathy , Gillott Cedric , Hegedus Dwayne D.
Published: April 2015

The peritrophic matrix (PM) is essential for insect digestive system physiology as it protects the midgut epithelium from damage by food particles, pathogens, and toxins. The PM is also an attractive target for development of new pest control strategies due to its per os accessibility. To understand how the PM performs these functions, the molecular architecture of the PM was examined using genomic and proteomic approaches in Mamestra configurata (Lepidoptera: Noctuidae), a major pest of cruciferous oilseed crops in North America. Liquid chromatography‐tandem mass spectrometry analyses of the PM identified 82 proteins classified as: (i) peritrophins, including a new class with a CBDIII domain; (ii) enzymes involved in chitin modification (chitin deacetylases), digestion (serine proteases, aminopeptidases, carboxypeptidases, lipases and α‐amylase) or other reactions (β‐1,3‐glucanase, alkaline phosphatase, dsRNase, astacin, pantetheinase); (iii) a heterogenous group consisting of polycalin, REPATs, serpin, C‐Type lectin and Lsti99/Lsti201 and 3 novel proteins without known orthologs. The genes encoding PM proteins were expressed predominantly in the midgut. cDNAs encoding chitin synthase‐2 (McCHS‐2), chitinase (McCHI), and β‐N‐acetylglucosaminidase (McNAG) enzymes, involved in PM chitin metabolism, were also identified. McCHS‐2 expression was specific to the midgut indicating that it is responsible for chitin synthesis in the PM, the only chitinous material in the midgut. In contrast, the genes encoding the chitinolytic enzymes were expressed in multiple tissues. McCHS‐2, McCHI, and McNAG were expressed in the midgut of feeding larvae, and NAG activity was present in the PM. This information was used to generate an updated model of the lepidopteran PM architecture.
A Survey of Nitrate and Nitrite Concentrations in Conventional and Organic‐Labeled Raw Vegetables at Retail
Authors: Nuñez de González Maryuri T. , Osburn Wesley N. , Hardin Margaret D. , Longnecker Michael , Garg Harsha K. , Bryan Nathan S. , Keeton Jimmy T.
Published: April 2015

A national survey of the nitrate () and nitrite ( ) concentrations in raw and highly consumed vegetables available at retail in the United States was conducted. A total of 194 samples of fresh broccoli, cabbage, celery, lettuce, and spinach categorized as conventional or organic by label were collected from 5 major cities in different geographic regions of the United States and analyzed to determine and concentrations. There were no differences in the mean values of conventional compared with organic vegetables taken from the 5 metropolitan areas. However, significant differences in mean pairwise comparisons between some conventional and organic vegetables for content were observed. The mean concentration of both conventional and organic vegetables ranged between 0.1 and 1.2 mg/kg of fresh weight (FW) with the exception of conventional spinach that contained 8.0 mg/kg FW. Mean contents of conventional broccoli, cabbage, celery, lettuce, and spinach were 394, 418, 1496, 851, and 2797 mg/kg FW, respectively, while their organic‐labeled counterparts averaged 204, 552, 912, 844, and 1318 mg/kg FW. In most cases, organic vegetables were numerically lower in content than their conventional counterparts. Based on survey results, the finding that low levels were observed in some organic vegetables in different cities may warrant further study to determine if true differences exist, due to production practices, seasonal differences, and the magnitudes of those differences. Furthermore, the geographic differences in content of vegetables may flaw estimates of daily and exposure.
Gender differences in the association between lifestyle behaviors and diabetes distress in a community sample of adults with type 2 diabetes
Authors: Lipscombe Carla , Smith Kimberley J. , Gariepy Geneviève , Schmitz Norbert
Published: April 2015

Background

The present study examined the association between moderate and severe diabetes distress (DD) and lifestyle behaviors (physical activity, smoking, alcohol consumption) in a community sample of adults with type 2 diabetes mellitus (T2DM).

Methods

A total of 1971 adults with T2DM were recruited using mixed methods sampling. Participants were considered eligible if they had a doctor diagnosis of T2DM (≤10 years), were insulin naïve, aged 40–75 years, and were from Quebec, Canada. Participants provided information on DD, lifestyle behaviors, sociodemographic, and diabetes‐related factors. Multinomial logistic regressions examined the association between moderate and severe DD and each lifestyle behavior, according to gender. Effect estimates can be interpreted as probability ratios (PR).

Results

In females, physical inactivity was associated with an increased likelihood of moderate distress (PR 2.2; 95% confidence interval [CI] 1.49–3.24) and severe distress (PR 1.80; 95% CI 1.00–3.24). In males, only severe distress was associated with physical inactivity (PR 1.92; 95% CI 1.00–3.66). Current smoking was associated with a greater probability of severe distress in males (PR 3.0; 95% CI 1.54–5.84) and females (PR 1.32; 95% CI 0.67–2.60); however this effect was stronger in males. No association was found between alcohol consumption and DD in females. In males, frequent alcohol consumption was associated with a reduced probability of moderate (PR 0.56; 95% CI 0.34–0.91) and severe distress (PR 0.47; 95% CI 0.21–1.06).

Conclusions

The findings of this study suggest important gender differences in the association between DD and lifestyle behaviors.
Development and validation of panoptic Meso scale discovery assay to quantify total systemic interleukin‐6
Authors: Chaturvedi Shalini , Siegel Derick , Wagner Carrie L. , Park Jaehong , van de Velde Helgi , Vermeulen Jessica , Fung Man‐Cheong , Reddy Manjula , Hall Brett , Sasser Kate
Published: April 2015

Aim

Interleukin‐6 (IL‐6), a multifunctional cytokine, exists in several forms ranging from a low molecular weight (MW 20–30 kDa) non‐complexed form to high MW (200–450 kDa), complexes. Accurate baseline IL‐6 assessment is pivotal to understand clinical responses to IL‐6‐targeted treatments. Existing assays measure only the low MW, non‐complexed IL‐6 form. The present work aimed to develop a validated assay to measure accurately total IL‐6 (complexed and non‐complexed) in serum or plasma as matrix in a high throughput and easily standardized format for clinical testing.

Methods

Commercial capture and detection antibodies were screened against humanized IL‐6 and evaluated in an enzyme‐linked immunosorbent assay format. The best antibody combinations were screened to identify an antibody pair that gave minimum background and maximum recovery of IL‐6 in the presence of 100% serum matrix. A plate‐based total IL‐6 assay was developed and transferred to the Meso Scale Discovery (MSD) platform for large scale clinical testing.

Results

The top‐performing antibody pair from 36 capture and four detection candidates was validated on the MSD platform. The lower limit of quantification in human serum samples (n = 6) was 9.77 pg l–1, recovery ranged from 93.13–113.27%, the overall pooled coefficients of variation were 20.12% (inter‐assay) and 8.67% (intra‐assay). High MW forms of IL‐6, in size fractionated serum samples from myelodysplastic syndrome and rheumatoid arthritis patients, were detected by the assay but not by a commercial kit.

Conclusion

This novel panoptic (sees all forms) IL‐6 MSD assay that measures both high and low MW forms may have clinical utility.
Bayesian hierarchical regression on clearance rates in the presence of “lag” and “tail” phases with an application to malaria parasites
Authors: Fogarty Colin B. , Fay Michael P. , Flegg Jennifer A. , Stepniewska Kasia , Fairhurst Rick M. , Small Dylan S.
Published: April 2015

We present a principled technique for estimating the effect of covariates on malaria parasite clearance rates in the presence of “lag” and “tail” phases through the use of a Bayesian hierarchical linear model. The hierarchical approach enables us to appropriately incorporate the uncertainty in both estimating clearance rates in patients and assessing the potential impact of covariates on these rates into the posterior intervals generated for the parameters associated with each covariate. Furthermore, it permits us to incorporate information about individuals for whom there exists only one observation time before censoring, which alleviates a systematic bias affecting inference when these individuals are excluded. We use a changepoint model to account for both lag and tail phases, and hence base our estimation of the parasite clearance rate only on observations within the decay phase. The Bayesian approach allows us to treat the delineation between lag, decay, and tail phases within an individual's clearance profile as themselves being random variables, thus taking into account the additional uncertainty of boundaries between phases. We compare our method to existing methodology used in the antimalarial research community through a simulation study and show that it possesses desirable frequentist properties for conducting inference. We use our methodology to measure the impact of several covariates on Plasmodium falciparum clearance rate data collected in 2009 and 2010. Though our method was developed with this application in mind, it can be easily applied to any biological system exhibiting these hindrances to estimation.
Prostatic arterial embolization for the treatment of lower urinary tract symptoms caused by benign prostatic hyperplasia: a comparative study of medium‐ and large‐volume prostates
Authors: Wang Maoqiang , Guo Liping , Duan Feng , Yuan Kai , Zhang Guodong , Li Kai , Yan Jieyu , Wang Yan , Kang Haiyan
Published: April 2015

Objectives

To compare the outcomes of prostatic arterial embolization (PAE) in treating large (>80 mL) in comparison with medium‐sized prostate glands (50–80 mL) to determine whether size affects the outcome of PAE.

Patients and Methods

A total of 115 patients (mean age 71.5 years) diagnosed with lower urinary tract symptoms (LUTS) attributable to benign prostatic hyperplasia (BPH) refractory to medical treatment underwent PAE. Group A (n = 64) included patients with a mean prostate volume of 129 mL; group B (n = 51) included patients with a mean prostate volume of 64 mL. PAE was performed using 100‐μm particles. Follow‐up was performed using the International Prostate Symptom Score (IPSS), quality of life (QoL), peak urinary flow rate (Qmax), post‐void residual urine volume (PVR), the International Index of Erectile Function short form (IIEF‐5), prostate‐specific antigen (PSA) and prostate volume measured by magnetic resonance imaging at 1, 3 and 6 months, and every 6 months thereafter.

Results

There were no significant differences between groups in baseline IPSS, QoL, Qmax, PVR, PSA level or IIEF‐5 score. The technical success rate was 93.8% in group A and 96.8% in group B (P = 0.7). A total of 101 patients (55 patients in group A and 46 patients in group B) completed the mean (range) follow‐up of 17 (12–33) months. Compared with baseline, there were significant improvements in IPSS, QoL, Qmax, prostate volume and PVR in both groups after PAE. The outcomes in group A were significantly better than in group B with regard to mean ± sd IPSS (−14 ± 6.5 vs −10.5 ± 5.5, respectively), Qmax (6.0 ± 1.5 vs 4.5 ± 1.0 mL/s, respectively), PVR (−80.0 ± 25.0 vs −60.0 ± 20.0 mL, respectively), prostate volume (−54.5 ± 18.0 mL [−42.3%] vs −18.5 ± 5.0 mL [−28.9%], respectively), and QoL score (−3.0 ± 1.5 vs −2.0 ± 1.0) with P values <0.05. The mean IIEF‐5 score was not significantly different from baseline in both groups. No major complications were noted.

Conclusions

We found that PAE is a safe and effective treatment method for patients with LUTS attributable to BPH. The clinical and imaging outcomes of PAE were better in patients with larger prostate glands than medium‐sized ones.