bluuebunny/crossref_metadata_2025 huggingface dataset:
DC flashover performance of ice‐covered insulators under complex ambient conditions
Authors: Hu Yuyao , Jiang Xingliang , Shu Lichun , Zhang Zhijin , Hu Qin , Hu Jianlin
Published: April 2016

The electrical characteristics of ice‐covered insulators in coexisting conditions of high altitude, icing and pollution are a basis for external insulation selection of transmission lines in icing regions. Ice accretion on insulators has been studied for decades, while few studies focus on the flashover performance of ice‐covered insulators polluted by two types of contamination, that is the solid layer method and icing water conductivity method, simultaneously. On the basis of the investigations on DC flashover performance of ice‐covered insulators in the artificial climate chamber, the influence of different parameters, such as insulator string length, icing water conductivity, salt deposit density as well as atmospheric pressure on DC icing flashover voltage of insulator strings is studied. According to the experimental results, the relationships between the flashover voltage and each of such factors are determined and analysed. Moreover, the correction formula for DC flashover voltage of ice‐covered insulators in complex ambient conditions is proposed.
Integrated particle smoothing for target tracking in clutter
Authors: Shi Yi Fang , Chong Sa Yong , Song Taek Lyul
Published: April 2016

The integrated particle filter (IPF) is an algorithm for single‐target tracking in clutter, which incorporates the probability of target existence (PTE) into the traditional particle filter as a track quality measure for false track discrimination (FTD). This study investigates two IPF‐based fixed‐interval smoothing algorithms: the IP smoothing (IPS) algorithm and the IP‐Rauch–Tung–Striebel backward smoothing (IP‐RTSBS) algorithm, both of which are capable of trajectory estimation and FTD. The IPS algorithm fuses the propagations for each pair of forward IPF and backward IPF particles to obtain the smoothing propagation that is used to update the track state by applying all available measurements in the current scan. The IP‐RTSBS algorithm employs the forward filtering backward smoothing approach to smooth the trajectory state, which is then applied to the RTS smoothing methodology to obtain the smoothing propagation used to update the PTE. As a result, both FTD and trajectory estimation are improved. The smoothing benefits of the two algorithms are validated in the simulations, where a sliding batch mode with overlapping measurements is utilised to limit the smoothing lag.
Doppler ambiguity removal and ISAR imaging of group targets with sparse decomposition
Authors: Huang Darong , Zhang Lei , Xing Mengdao , Bao Zheng
Published: April 2016

Low pulse repetition frequency waveforms inherently suffer from the Doppler ambiguity in inverse synthetic aperture radar (ISAR) imaging of group targets. In this study, a novel Doppler ambiguity removal method with sparse decomposition is presented for ISAR imaging of group targets. By solving a sparsity‐driven optimisation problem, chirp signals corresponding to scattering centres of group targets are extracted in the azimuth time‐domain, and the Doppler ambiguity number of each extracted chirp signal can be estimated simultaneously in the process of sparse decomposition. As a result, unambiguous ISAR image of group targets can be well reconstructed by a sophisticated compensation of migration through range cells and the time‐varying Doppler. Extensive simulated experiments confirm the effectiveness of the proposal.
Melatonin in Critically Ill Children
Authors: Foster Jennifer
Published: April 2016

Melatonin, while best known for its chronobiologic functions, has multiple effects that may be relevant in critical illness. It has been used for circadian rhythm maintenance, analgesia, and sedation, and has antihypertensive, anti-inflammatory, antioxidant, antiapoptotic, and antiexcitatory effects. This review examines melatonin physiology in health, the current state of knowledge regarding endogenous melatonin production in pediatric critical illness, and the potential uses of exogenous melatonin in this population, including relevant information from basic sciences and other fields of medicine. Pineal melatonin production and secretion appears to be altered in critical illness, though understanding in pediatric critical illness is in early stages, with only 102 children reported in the current literature. Exogenous melatonin may be used for circadian rhythm disturbances and, within the critically ill population, holds promise for diseases involving oxidant stress. There are no studies of exogenous melatonin administration to critically ill children beyond the neonatal period.
Dielectric nanoresonator based lossless optical perfect magnetic mirror with near-zero reflection phase
Authors: Lin Lan , Jiang Zhi Hao , Ma Ding , Yun Seokho , Liu Zhiwen , Werner Douglas H. , Mayer Theresa S.
Published: April 2016

We report an all-dielectric lossless optical mirror for the realization of controllable reflection phase based on an array of isolated dielectric nanoresonators. This dielectric mirror is comprised of a cross-shaped amorphous silicon nanoresonator array that has been designed to achieve a 99.8% reflectivity and zero reflection phase at the wavelength of 0.99 μm. The measured results from the fabricated sample match the theoretical predictions with 99.5% reflectivity and near-zero degree reflection phase at 1 μm, which is very close to the targeted wavelength. This concept and approach pave the way for synthesizing lossless artificial reflecting electromagnetic boundaries with arbitrary phase response and hold great promise in applications ranging from nanocavities to nanowaveguides and nanoantennas.
A two-step process for growth of highly oriented Sb2Te3 using sputtering
Authors: Saito Yuta , Fons Paul , Bolotov Leonid , Miyata Noriyuki , Kolobov Alexander V. , Tominaga Junji
Published: April 2016

A two-step growth method is proposed for the fabrication of highly-oriented Sb2Te3 and related superlattice films using sputtering. We report that the quality and grain size of Sb2Te3 as well as GeTe/Sb2Te3 superlattice films strongly depend on the thickness of the room-temperature deposited and subsequently by annealing at 523 K Sb2Te3 seed layer. This result may open up new possibilities for the fabrication of two-dimensional electronic devices using layered chalcogenides.
Spin density waves predicted in zigzag puckered phosphorene, arsenene and antimonene nanoribbons
Authors: Wu Xiaohua , Zhang Xiaoli , Wang Xianlong , Zeng Zhi
Published: April 2016

The pursuit of controlled magnetism in semiconductors has been a persisting goal in condensed matter physics. Recently, Vene (phosphorene, arsenene and antimonene) has been predicted as a new class of 2D-semiconductor with suitable band gap and high carrier mobility. In this work, we investigate the edge magnetism in zigzag puckered Vene nanoribbons (ZVNRs) based on the density functional theory. The band structures of ZVNRs show half-filled bands crossing the Fermi level at the midpoint of reciprocal lattice vectors, indicating a strong Peierls instability. To remove this instability, we consider two different mechanisms, namely, spin density wave (SDW) caused by electron-electron interaction and charge density wave (CDW) caused by electron-phonon coupling. We have found that an antiferromagnetic Mott-insulating state defined by SDW is the ground state of ZVNRs. In particular, SDW in ZVNRs displays several surprising characteristics:1) comparing with other nanoribbon systems, their magnetic moments are antiparallelly arranged at each zigzag edge and almost independent on the width of nanoribbons; 2) comparing with other SDW systems, its magnetic moments and band gap of SDW are unexpectedly large, indicating a higher SDW transition temperature in ZVNRs; 3) SDW can be effectively modified by strains and charge doping, which indicates that ZVNRs have bright prospects in nanoelectronic device.
Validation of age determination using otoliths of the European anchovy (Engraulis encrasicolus L.) in the Bay of Biscay
Authors: Uriarte A. , Rico I. , Villamor B. , Duhamel E. , Dueñas C. , Aldanondo N. , Cotano U.
Published: April 2016

Validation of the age determination procedure using otoliths of European anchovy in the Bay of Biscay was achieved by monitoring very strong year-classes in successive spring catches and surveys, as well as the seasonal occurrence of edge types. Historical corroboration of the ageing method was obtained by cross-correlation between successive age groups by year-classes in catches and surveys (1987–2013). Summary annual growth in length is also presented. Yearly annuli consist of a hyaline zone (either single or composite) and a wide opaque zone, disrupted occasionally by some typical checks (mainly at age-0 and age-1 at peak spawning time). Age determination, given a date of capture, requires knowledge of the typical annual growth pattern of otoliths, their seasonal edge formation by ages and the most typical checks. Most opaque growth occurs in summer and is minimal (translucent) in winter. Opaque zone formation begins earlier in younger fish (in spring), and this helps distinguish age-1 from age-2+.
Resolution of Myelofibrosis‐Associated Pulmonary Arterial Hypertension following Allogeneic Hematopoietic Stem Cell Transplantation
Authors: Faiz Saadia A. , Iliescu Cezar , Lopez‐Mattei Juan , Patel Bela , Bashoura Lara , Popat Uday
Published: April 2016

We present the case of a 62‐year‐old man with myelofibrosis‐associated pulmonary arterial hypertension (PAH) who underwent allogeneic hematopoietic stem cell transplantation with subsequent resolution of disease and PAH. Right heart catheterization was used to guide PAH therapy before and after transplantation. Drug interactions, adverse effects, and renal insufficiency posed clinical challenges for the management of PAH‐specific medications after transplantation. PAH improved soon after transplantation, and vasoactive medications were tapered off. Resolution of PAH was confirmed with repeat measurement of pulmonary hemodynamic characteristics. Although the etiology and pathophysiology for the resolution of PAH was unclear, the myelopulmonary pathophysiologic link was likely to have contributed. This is the first report describing resolution of myelofibrosis‐associated PAH after allogeneic hematopoietic stem cell transplantation.
Complementary and Alternative Medicine in Multiple Sclerosis
Authors: Bowling Allen C.
Published: April 2016

Many patients with multiple sclerosis use complementary and alternative medicine (CAM). However, health professionals may have limited knowledge about CAM therapies and may not know which CAM therapies are being used by patients who are under their care. These CAM therapies may be beneficial or harmful and may interact with conventional multiple sclerosis medications. Therefore, quality of care may be improved if clinicians have the skills and knowledge to provide unbiased, evidence-based CAM information to patients and, when appropriate, to guide patients away from harmful or ineffective therapies and toward low-risk, possibly effective therapies. This chapter provides information to practicing clinicians so that they will be able to guide and inform their patients with multiple sclerosis about CAM.
Normal physiology of the respiratory system
Authors: Hedenstierna Göran , Borges João Batista
Published: April 2016

The lungs contain 200–300 million alveoli that are reached via 23 generations of airways. The volume in the lungs after an ordinary expiration is called functional residual capacity (FRC) and is approximately 3–4 L. The lung is elastic and force (pressure) is needed to expand it and to overcome the resistance to gas flow in the airways. This pressure can be measured as pleural minus alveolar pressure. The inspired volume goes mainly to dependent, lower lung regions, but with increasing age and in obstructive lung disease airways may close in dependent lung regions during expiration, impeding oxygenation of the blood. With lowered functional residual capacity,airways may be continuously closed with subsequent gas adsorbtion from the closed off alveoli. Perfusion of the lung goes also mainly to dependent regions, but there is in addition, possibly more important, a non-gravitational inhomogeneity. A ventilation-perfusion mismatch may ensue that impedes oxygenation and CO2 removal, but can to some extent be corrected for by hypoxic pulmonary vasoconstriction.
Aspiration of gastric contents in the critically ill
Authors: Froio Sara , Valenza Franco
Published: April 2016

This chapter focuses on the pathophysiology, clinical features, management and prevention of aspiration pneumonitis, aspiration pneumonia, and airway obstruction. Aspiration is defined as the inhalation of oropharyngeal or gastric contents into the larynx and lower respiratory tract. Pulmonary syndromes caused by aspiration are different, depending on the amount and nature of the aspirated material, the frequency of aspiration and the host’s response. This results in a chemical burn of tracheobronchial tree and pulmonary parenchyma. The caustic effects of the low pH of the aspirate cause an intense inflammatory reaction. As a consequence, severe hypoxaemia and infiltrates on chest radiograph occur. If colonized oropharyngeal material enters the lungs, aspiration pneumonia develops and antibiotics are needed. Even if not toxic per se, large volumes of fluids may cause suffocation by mechanical obstruction. Prevention of aspiration is of vital importance and the patient at risk must be identified. The major therapeutic approach is to correct hypoxia, support pulmonary function, and prevent pneumonia development.
Pathophysiology of acute respiratory distress syndrome
Authors: Ware Lorraine B.
Published: April 2016

The acute respiratory distress syndrome (ARDS) is a syndrome of acute respiratory failure characterized by the acute onset of non-cardiogenic pulmonary oedema due to increased lung endothelial and alveolar epithelial permeability. Common predisposing clinical conditions include sepsis, pneumonia, severe traumatic injury, and aspiration of gastric contents. Environmental factors, such as alcohol abuse and cigarette smoke exposure may increase the risk of developing ARDS in those at risk. Pathologically, ARDS is characterized by diffuse alveolar damage with neutrophilic alveolitis, haemorrhage, hyaline membrane formation, and pulmonary oedema. A variety of cellular and molecular mechanisms contribute to the pathophysiology of ARDS, including exuberant inflammation, neutrophil recruitment and activation, oxidant injury, endothelial activation and injury, lung epithelial injury and/or necrosis, and activation of coagulation in the airspace. Mechanical ventilation can exacerbate lung inflammation and injury, particularly if delivered with high tidal volumes and/or pressures. Resolution of ARDS is complex and requires coordinated activation of multiple resolution pathways that include alveolar epithelial repair, clearance of pulmonary oedema through active ion transport, apoptosis, and clearance of intra-alveolar neutrophils, resolution of inflammation and fibrinolysis of fibrin-rich hyaline membranes. In some patients, activation of profibrotic pathways leads to significant lung fibrosis with resultant prolonged respiratory failure and failure of resolution.
Lactate monitoring in the ICU
Authors: Jansen Tim C. , Bakker Jan
Published: April 2016

An increased blood lactate level (hyperlactataemia) is commonplace in critically-ill patients. Lactate is usually measured with the aim of detecting tissue hypoxia, but this is an oversimplification as aerobic processes can also result in increased levels. Understanding of the various anaerobic and aerobic mechanisms of production and clearance is essential for the correct interpretation of hyperlactataemia. Despite the broad differential diagnosis, hyperlactataemia generally predicts adverse outcomes. The consistency of its prognostic value emphasizes its place in the risk stratification of critically-ill patients. Lactate clearance was non-inferior to central venous oxygen saturation as a goal of early resuscitation in patients presenting to the emergency department with severe sepsis or septic shock. Therapy guidance by lactate monitoring significantly reduced hospital mortality in ICU patients admitted with hyperlactataemia after adjustment for predefined risk factors, a finding consistent with important secondary endpoints. These results confirm that lactate monitoring offers clinical benefit and should be incorporated within a goal-directed therapy strategy.
Complex midface reconstruction following tumour ablation
Authors: Aga Hiba , Al-Qamachi Laith , Idle Matthew , Grew Nicholas
Published: April 2016

Malignancy in the maxilla tends to be occult with late presentation and thus carries a relatively poor survival rate. The complexity of this region as a three-dimensional structure presents significant challenges to the reconstructive surgeon. A case history of a squamous cell carcinoma in an inverted papilloma of the maxillary antrum is presented with detailed commentary from an expert in head and neck oncological ablation and reconstruction. The most recent Brown classification is presented in connection to this case. The multidisciplinary management of this disease is discussed with reference to the place of chemotherapy and radiotherapy with overall emphasis on the free flap reconstruction of a large, complex defect of the midface.
Management of osteoradionecrosis of the mandible
Authors: Abdullakutty Anwer , D’Souza Jacob , Rogers Simon
Published: April 2016

Osteoradionecrosis (ORN) of the mandible is often severe and a debilitating condition. A 67-year-old male presented with a non-healing tooth extraction socket in the region of lower left second molar. This patient with a previous history of radiotherapy for oral squamous cell carcinoma and biopsy to rule out recurrent disease confirmed ORN. ORN preferentially affects the mandible due to its poor blood supply. Various classification systems have been proposed and they differ in clinical value. Treatment strategies vary amongst clinicians, ranging from the use of antibiotics to surgical debridement and hyperbaric oxygen therapy. More recently, medical management with pentoxifylline, tocopherol, and clodronate is gaining popularity in selected cases of established ORN. Radical excision of necrotic bone and soft tissue followed by free tissue transfer should be given due consideration in carefully selected patients. We provide an overview of the historical and contemporary management of ORN and discuss appropriate management strategies.
Frontal sinus fractures
Authors: Singh Rabindra , Carter Lachlan
Published: April 2016

This chapter describes the principles of management of frontal sinus fracture including clinical assessment, investigations, fracture classification, frontal sinus anatomy, treatment, complications, and follow-up. A detailed description of a case treated by the authors is provided with information on surgical technique. Several areas in frontal sinus fracture management are controversial, which are highlighted and pertinent literature discussed.
Biomechanics of the mandible and current evidence for treatment of the fractured mandible
Authors: Hammond Douglas , Messahel Ahmed
Published: April 2016

An exploration of the biomechanics, evidence and principles behind the treatment of mandibular fractures. We present a case involving interpersonal violence causing a bilateral fractured mandible with an associated segmental fracture. Discussion centres on the method used for maxillomandibular fixation and the sequencing of the operative procedure. The work carried out by Champy relating to biomechanics is presented and referenced to the implications on clinical management of all mandibular fractures. The Cochrane review, however, states that there is inadequate evidence to support the effectiveness of a single approach in the management of mandibular fractures when the condyle is not involved. Thus sound knowledge of all the techniques available is required to manage mandibular fractures on a case-by-case basis.
Severe Class II skeletal deformity
Authors: Greaney Lisa , Sneddon Ken , Collyer Jeremy
Published: April 2016

The Class II skeletal pattern can result in both functional and aesthetic disturbances. Where the deformity is significant it is often associated with diminutive condyles and reduced posterior face height. We present a case of a severe Class II malocclusion also known as the ‘bird-face’ deformity. Various techniques are discussed with reference to the management of these cases. The ultimate goal is to produce a stable Class I occlusion with minimal morbidity from the surgical procedure. Where such significant retrognathic cases are planned on the joint clinic the risk of condylar resorption should also be borne in mind.
The segmental maxillary osteotomy
Authors: Ahmed Nabeela , Srinivasan Dilip
Published: April 2016

The indications for segmental surgery as part of an orthognathic treatment plan are fairly limited. However, when it is undertaken careful clinical, radiographic, and articulated model assessment of the deformity should be undertaken. One of the principal aims should be achievement of the correct position of the maxillary central incisors. We present a case of a 16-year-old female who presented with an anterior open bite with posterior maxillary excess. Via the joint orthognathic clinic she underwent a segmental maxillary procedure with a concurrent mandibular sagittal split osteotomy. The operative details are discussed with significant note made to the potential complications of this difficult surgery. Consideration of soft tissue changes following this surgery are discussed; notably reduction in labial prominence and increase in nasolabial angle.
Temporomandibular joint replacement
Authors: Ahmed Nabeela , Sidebottom Andrew
Published: April 2016

Progressive condylar resorption can result in a Class II skeletal pattern that worsens over time. Several options exist for management but total replacement of the temporomandibular joint is probably the most reliable. We present a case of a 17-year-old with the ‘bird-face’ deformity secondary to condylar resorption. Once cross-sectional imaging and patch testing were carried out the patient underwent total replacement of both joints. Current indications for joint replacement are discussed in conjunction with access to the joint and the surgical technique. Finally alternatives to joint replacement are discussed for those patients who are unsuitable for joint replacement or do not wish to undergo this procedure.
Salivary calculi
Authors: Haq Jahrad , McGurk Mark
Published: April 2016

The aetiology of salivary gland stones is still not fully understood. The prevalence of symptomatic salivary gland stones in the UK is 5.9 per 100,000 and represents the majority of salivary gland pathology in middle-aged patients. The submandibular is the most common site, followed by the parotid and sublingual glands. We present a case involving a 50-year-old patient with a three-month history of recurrent left parotid swelling. This was discussed in a multidisciplinary one-stop salivary gland clinic. The patient was subsequently diagnosed with a stone in the left parotid duct. Evidence is presented pertaining to both surgical and non-surgical management and this case discusses a combination of these approaches to render the patient symptom-free.
Paediatric maxillofacial trauma
Authors: Ujam Atheer , Thomas Suraj , Holmes Simon
Published: April 2016

Maxillofacial trauma in children is markedly different to their adult counterparts. The facial skeleton contains significant growth potential with inherent elasticity at this stage. There is also a differing cranial to facial bone ratio with 0.5:0.5 in infants changing to 0.33:0.67 in adults. The sinuses in small children are also at a rudimentary stage and developing tooth buds are also present. We present two cases in this chapter. The first is a six-year old attending with a left orbital floor fracture in a state of physiological compromise. The second is an 11-year-old with bilateral displaced condyles as part of a ‘guardsman’s fracture’ of the mandible. The treatment of both is discussed at length taking the difficulties in examination, consent and treatment for this cohort of patients into consideration.
Friedmann–Robertson–Walker models do not require zero active mass
Authors: Kim Do Young , Lasenby Anthony N. , Hobson Michael P.
Published: April 2016

The Rh = ct cosmological model has received considerable attention in recent years owing to claims that it is favoured over the standard Λ cold dark mater (ΛCDM) model by most observational data. A key feature of the Rh = ct model is that the zero active mass condition ρ + 3p = 0 holds at all epochs. Most recently, Melia has claimed that this condition is a requirement of the symmetries of the Friedmann–Robertson–Walker spacetime. We demonstrate that this claim is false and results from a flaw in the logic of Melia's argument.
MicroRNA-183-96-182 Cluster Regulates Bovine Granulosa Cell Proliferation and Cell Cycle Transition by Coordinately Targeting FOXO11
Authors: Gebremedhn Samuel , Salilew-Wondim Dessie , Hoelker Michael , Rings Franca , Neuhoff Christiane , Tholen Ernst , Schellander Karl , Tesfaye Dawit
Published: April 2016

Large-scale expression profiling of micro-RNAs (miRNAs) in bovine granulosa cells from dominant and subordinate follicles on Day 19 of the estrous cycle revealed enriched micro-RNA-183-96-182 cluster miRNAs in preovulatory dominant follicles that coordinately regulate the forkhead box protein O1 (FOXO1) gene. However, little is known about the role of this cluster in bovine granulosa cell function. We used an in vitro granulosa cell culture model to investigate this role. Granulosa cells aspirated from small growing follicles (3–5 mm in diameter) were cultured in Dulbecco modified Eagle medium/F-12 medium supplemented with fetal bovine serum and transfected with locked nucleic acid-based miRNA mimics, inhibitors, and corresponding negative controls. Overexpression of the miRNA cluster resulted in suppression of FOXO1 mRNA and protein, whereas inhibition of the cluster increased expression of FOXO1 mRNA. Overexpression also increased the relative rate of cell proliferation, whereas inhibition slowed it down. Similarly, the proportion of cells under G0/G1 arrest declined, whereas the ratio of cells in S phase increased in response to miR-183-96-182 overexpression. Selective knockdown of FOXO1 mRNA using anti-FOXO1 small interfering RNA increased the rate of granulosa cell proliferation, decreased the proportion of cells under G0/G1 arrest, and increased the proportion of cells in the S phase of cell cycle. Our data suggest that miR-183-96-182 cluster miRNAs promote proliferation and G1/S transition of bovine granulosa cells by coordinately targeting FOXO1, suggesting a critical role in granulosa cell function. MicroRNA-183-96-182 cluster regulates bovine granulosa cell function by targeting FOXO1 gene.
Association Between Tibial Malunion Deformity Parameters and Degenerative Hip and Knee Disease
Authors: Weinberg Douglas S. , Park Paul J. , Liu Raymond W.
Published: April 2016

Objectives:

Tibia fractures are the most common long bone fracture. Criteria for closed and open reduction are based on the amount of fracture shortening, angulation, and rotation, with high success rates achieved if acceptable alignment is maintained. However, there exists limited data available regarding the long-term consequences of specific deformation patterns.

Methods:

The tibiae of 2898 cadaveric skeletons were manually inspected for evidence of fracture. Specimens with midshaft fractures were identified as candidates for study; intraarticular fractures were excluded. Fracture shortening, location, angulation, rotation (torsion), and translation were measured using previously described techniques. Degenerative joint disease of the knee and hip was graded from 0 to 3 in fracture specimens using a previously published system. Correlations between fracture characteristic and osteoarthritis were evaluated.

Results:

Thirty-seven tibia fractures were present in 36 skeletons. In patients with tibia fractures, ipsilateral knee arthritis was greater than that of the contralateral side (P < 0.001). Knee arthritis was greater in fractures with coronal plane deformity greater than 5 degrees (P = 0.006) and with rotational deformity greater than 10 degrees (P = 0.004). There were no differences in knee arthritis based on laterality, shortening, sagittal deformity, fracture type, or translation in any plane (P > 0.05 for all). There were no differences in hip arthritis on the ipsilateral side compared with the contralateral side (P = 0.149). However, tibiae that were shortened by more than 10 mm had higher grades of ipsilateral hip arthritis (P = 0.009).

Conclusions:

The results of this study suggest that coronal and axial plane malalignment and shortening are of the greatest consequence following tibia fracture. These conclusions strengthen the recommendations of authors who have emphasized restoring tibial length following fracture, and providing anatomic restoration in the coronal and axial planes.
Membrane Induced Osteogenesis in the Management of Posttraumatic Bone Defects
Authors: Azi Matheus L. , Teixeira Armando Augusto de A. , Cotias Ricardo B. , Joeris Alexander , Kfuri Mauricio
Published: April 2016

Objective:

To evaluate the union rate of posttraumatic bone defects treated with the induced membrane technique.

Design:

Single-center retrospective case series.

Setting:

Level I trauma center.

Patients/Participants:

Thirty-three patients who sustained 34 posttraumatic bone defects (19 tibia, 15 femur).

Intervention:

Staged management using the induced membrane technique described by Masquelet. After extensive debridement at the fracture site, a polymethylmethacrylate (PMMA) spacer was inserted into the resulting void. After soft tissue recovery, the spacer was removed, and the void, now enveloped by an induced membrane, was filled with an autologous iliac crest bone graft.

Main Outcome Measures:

Bone union rate, time to achieve bone union, length of hospital stay, number of surgeries, infection resolution, range of motion, musculoskeletal tumor society system functional score, and limb shortening.

Results:

The mean defect size was 6.7 cm, and infection was present in 23 (68%) of the bone defects. Bone union was evident in 91% of cases (31/34). The average time to union was 8.5 months. In 7 of 23 (30%) of infected cases, the infection recurred, and in 3 of them, the graft was resorbed, resulting in treatment failure.

Conclusion:

The induced membrane technique was effective for managing posttraumatic bone defects. A recurrence of infection was associated with treatment failure.

Level of Evidence:

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.
Curcumin Lowers Serum Lipids and Uric Acid in Subjects With Nonalcoholic Fatty Liver Disease: A Randomized Controlled Trial
Authors: Panahi Yunes , Kianpour Parisa , Mohtashami Reza , Jafari Ramezan , Simental-Mendía Luis E. , Sahebkar Amirhossein
Published: April 2016

Background:

Nonalcoholic fatty liver disease (NAFLD) is one of the most common hepatic diseases in the general adult population. Dyslipidemia, hyperuricemia, and insulin resistance are common risk factors and accompanying features of NAFLD. Curcumin is a dietary natural product with beneficial metabolic effects relevant to the treatment of NAFLD.

Aim:

To assess the effects of curcumin on metabolic profile in subjects with NAFLD.

Methods:

Patients diagnosed with NAFLD (grades 1–3; according to liver sonography) were randomly assigned to curcumin (1000 mg/d in 2 divided doses) (n = 50) or control (n = 52) group for a period of 8 weeks. All patients received dietary and lifestyle advises before the start of trial. Anthropometric measurements, lipid profile, glucose, insulin, glycated hemoglobin, and uric acid concentrations were measured at baseline and after 8 weeks of follow-up.

Results:

Eighty-seven subjects (n = 44 and 43 in the curcumin and control group, respectively) completed the trial. Supplementation with curcumin was associated with a reduction in serum levels of total cholesterol (P < 0.001), low-density lipoprotein cholesterol (P < 0.001), triglycerides (P < 0.001), non–high-density lipoprotein cholesterol (P < 0.001), and uric acid (P < 0.001), whereas serum levels of high-density lipoprotein cholesterol and glucose control parameters remained unaltered. Curcumin was safe and well tolerated during this study.

Conclusion:

Results of the present trial suggest that curcumin supplementation reduces serum lipids and uric acid concentrations in patients with NAFLD.
Patients With Celiac Disease Reported Higher Consumption of Added Sugar and Total Fat Than Healthy Individuals
Authors: Babio Nancy , Alcázar Mireia , Castillejo Gemma , Recasens Miriam , Martínez‐Cerezo Francesc , Gutiérrez‐Pensado Vanessa , Masip Guiomar , Vaqué Cristina , Vila‐Martí Anna , Torres‐Moreno Miriam , Sánchez Enric , Salas‐Salvadó Jordi
Published: April 2016

Objectives:

The aim of the study was to compare the dietary pattern between subjects with celiac disease (CD) (cases) and subjects without (healthy controls) CD.

Methods:

A case‐control design study was conducted. A total of 98 subjects with CD (age 10–23 years) were matched by age, sex, and body mass index with 98 nonceliac participants. A nonconsecutive 3‐day food record was completed to assess energy, nutrient, and food intake and evaluate the participant's adherence to recommendations. Differences in energy, nutrients, food consumption, and compliance with general recommendations between cases and control groups were assessed by Student t test. Pearson chi‐squared test was used to compare categorical variables. Sociodemographic, personal, and family history data were collected.

Results:

Compared with the control group, the cases with CD reported a significantly higher consumption of added sugar (P < 0.001) and total fat (P < 0.017). Mean fiber consumption was below the nutritional recommendations in both groups. Participants with CD consumed significantly lower amounts of foods rich in starch (P < 0.001) and higher amounts of foods rich in protein such as meat, fish, and eggs (P = 0.007). Subjects with CD showed a significantly lower percentage of adherence to recommendations for folic acid (53.2 vs 70.5; P < 0.001), calcium (49.0 vs 56.3; P = 0.025), iron (57.4 vs 78.0; P < 0.001), and magnesium (50.0 vs 63.9; P < 0.001).

Conclusions:

The subjects with CD showed a more unbalanced diet than controls in terms of added sugars, total fat, and micronutrient consumption.
Pediatric Pleomorphic Xanthoastrocytoma Treated With Surgical Resection Alone: Clinicopathologic Features
Authors: Dodgshun Andrew J. , Sexton-Oates Alexandra , Saffery Richard , MacGregor Duncan , Sullivan Michael J.
Published: April 2016

Pleomorphic xanthoastrocytoma (PXA) is a rare brain tumor that usually occurs in children and young adults. It has characteristic histologic features and is regarded as a WHO grade II lesion. Overall survival is reported to be >60%, but published series usually consist of a range of ages and treatment modalities. Gross total resection is associated with superior survival but recurrence rates after gross total resection are not well described, particularly in a pediatric population. We describe 16 cases over 20 years at our institution of pediatric PXA treated with surgical resection alone with a 5-year relapse-free survival of 40% (95% confidence interval, 20%-82%) and overall survival of 76% (95% confidence interval, 55%-100%). Gross total resection was associated with superior relapse-free survival (P<0.05). Some cases have a very long period between symptom onset or radiologic detection and resection, but neither length of symptoms nor radiologic signs of slow growth were associated with survival. PXA is a rare and unusual entity with unpredictable behavior. Complete surgical resection is optimal but does not guarantee relapse-free survival. We propose separation of PXA from other low-grade gliomas in childhood given differing biology and behavior.
Effects of Surfactant Lavage Combined With Intratracheal Budesonide Instillation on Meconium-Injured Piglet Lungs
Authors: Lin Chih-Hsueh , Jeng Mei-Jy , Kuo Benjamin Ing-Tiau , Kou Yu Ru
Published: April 2016

Objectives:

To evaluate the combined effects of surfactant lavage and intratracheally instillation of budesonide on meconium-injured piglet lungs.

Design:

A prospective, randomized, animal model study.

Setting:

An experimental laboratory.

Subjects:

Twenty-four anesthetized and mechanically ventilated newborn piglets.

Interventions:

Human meconium slurry was intratracheally instilled into piglet lungs to induce lung injury. The injured piglets were randomly assigned to either the sham treatment group (control) or one of the three therapeutic groups: the intratracheally instilled budesonide (Bud) group, the bronchoalveolar lavage with diluted surfactant (dsBAL) group, and the combination therapy of Bud and dsBAL (dsBAL + Bud) group.

Measurements and Main Results:

Cardiopulmonary profiles were measured hourly. Proinflammatory cytokine (interleukin-1β, interleukin-6, and interleukin-8) levels in bronchoalveolar lavage fluid were measured. Finally, the pulmonary histology of the experimental subjects was examined at the end of experiments. Both of the lavaged groups (dsBAL and dsBAL + Bud) showed significantly better oxygenation than those that had not undergone lavage (control and Bud) (p < 0.05). The dsBAL + Bud group showed a significantly higher lung compliance and required a significantly lower peak inspiratory pressure during the experimental periods than the other three groups (p < 0.05). All treatment groups had significantly lower concentrations of interleukin-1β concentration in the bronchoalveolar lavage fluid than the control group (p < 0.05). The dsBAL + Bud group also had a significantly lower interleukin-6 concentration in the bronchoalveolar lavage fluid (p< 0.05), as well as a significantly lower lung injury score based on pulmonary histology than the control group (p < 0.05).

Conclusions:

Therapeutic bronchoalveolar lavage with diluted surfactant followed by intratracheal instillation of budesonide has a synergistic and beneficial effect when treating severe meconium-injured newborn piglet lungs.
Procalcitonin in the Early Course Post Pediatric Cardiac Surgery
Authors: Zant Robert , Stocker Christian , Schlapbach Luregn Jan , Mayfield Sara , Karl Tom , Schibler Andreas
Published: April 2016

Objective:

Procalcitonin has emerged as a promising infection marker, but previous reports from small-sized studies suggest nonspecific elevation of procalcitonin after pediatric heart surgery. As procalcitonin is increasingly used as a marker for infection in the PICU, the aim of this study was to identify factors associated with postoperative procalcitonin elevation and to investigate the role of procalcitonin as an early marker of outcome after cardiac surgery.

Design:

Prospective observational study.

Setting:

Single, tertiary referral PICU.

Patients:

Patients aged 0–16 years following cardiac surgery with or without cardiopulmonary bypass.

Interventions:

Procalcitonin was measured in all patients at admission to PICU, and on postoperative day 1 and 2. Outcome variables included major adverse event, length of stay in PICU, postoperative renal failure requiring temporary dialysis, duration of mechanical ventilation and duration of inotropic support. A major adverse event was defined as cardiac arrest, need for postoperative extracorporeal life support or death within 3 months of cardiac surgery.

Measurements and Main Results:

In 221 included patients who underwent 232 operations, procalcitonin at admission to PICU was significantly associated with mechanical ventilation prior to surgery (p = 0.001), preoperative myocardial dysfunction (p = 0.002), duration of cardiopulmonary bypass (p < 0.001), intraoperative cross-clamp time (p = 0.015), and serum lactate at admission (p < 0.001). Patients suffering a major adverse event and patients with postoperative renal failure had significantly higher procalcitonin levels at admission to PICU (p = 0.04 and 0.01, respectively). Furthermore, procalcitonin levels at admission correlated significantly with the length of stay in the PICU (p = 0.005), time on mechanical ventilation (p = 0.03), and duration of inotropic support (p = 0.02).

Conclusions:

Elevated levels of procalcitonin in the early phase after pediatric cardiac surgery are a marker for increased risk for major adverse events and postoperative renal failure and increased postoperative morbidity.
Comparison of Pediatric Severe Sepsis Managed in U.S. and European ICUs*
Authors: Giuliano John S. , Markovitz Barry P. , Brierley Joe , Levin Richard , Williams Gary , Lum Lucy Chai See , Dorofaeff Tavey , Cruces Pablo , Bush Jenny L. , Keele Luke , Nadkarni Vinay M. , Thomas Neal J. , Fitzgerald Julie C. , Weiss Scott L.
Published: April 2016

Objectives:

Pediatric severe sepsis remains a significant global health problem without new therapies despite many multicenter clinical trials. We compared children managed with severe sepsis in European and U.S. PICUs to identify geographic variation, which may improve the design of future international studies.

Design:

We conducted a secondary analysis of the Sepsis PRevalence, OUtcomes, and Therapies study. Data about PICU characteristics, patient demographics, therapies, and outcomes were compared. Multivariable regression models were used to determine adjusted differences in morbidity and mortality.

Setting:

European and U.S. PICUs.

Patients:

Children with severe sepsis managed in European and U.S. PICUs enrolled in the Sepsis PRevalence, OUtcomes, and Therapies study.

Interventions:

None.

Measurements and Main Results:

European PICUs had fewer beds (median, 11 vs 24; p < 0.001). European patients were younger (median, 1 vs 6 yr; p < 0.001), had higher severity of illness (median Pediatric Index of Mortality-3, 5.0 vs 3.8; p = 0.02), and were more often admitted from the ward (37% vs 24%). Invasive mechanical ventilation, central venous access, and vasoactive infusions were used more frequently in European patients (85% vs 68%, p = 0.002; 91% vs 82%, p = 0.05; and 71% vs 50%; p < 0.001, respectively). Raw morbidity and mortality outcomes were worse for European compared with U.S. patients, but after adjusting for patient characteristics, there were no significant differences in mortality, multiple organ dysfunction, disability at discharge, length of stay, or ventilator/vasoactive-free days.

Conclusions:

Children with severe sepsis admitted to European PICUs have higher severity of illness, are more likely to be admitted from hospital wards, and receive more intensive care therapies than in the United States. The lack of significant differences in morbidity and mortality after adjusting for patient characteristics suggests that the approach to care between regions, perhaps related to PICU bed availability, needs to be considered in the design of future international clinical trials in pediatric severe sepsis.
An Algorithmic Approach to the Surgical Treatment of Chronic Ischemia of the Hand: A Systematic Review of the Literature
Authors: Thibaudeau Stephanie , Serebrakian Arman T. , Gerety Patrick A. , Levin L. Scott
Published: April 2016

Background:

Chronic ischemia of the hand can lead to intractable pain, cold intolerance, and digital necrosis, affecting up to 4.8 percent of patients undergoing vascular surgery. Treatment of patients suffering from chronic hand ischemia, in particular, the subset of patients with a nonreconstructible distal arterial tree, can be a significant challenge for hand surgeons. The purpose of this systematic review is to analyze the outcomes of surgical therapies in an effort to define the efficacy of each intervention. The authors also revisit the treatment algorithm for nontraumatic chronic hand ischemia.

Methods:

A systematic search of the literature published since 1990 in the PubMed/MEDLINE database was performed using keywords. Articles were eligible if they described clinical studies of human patients with nontraumatic chronic hand ischemia who underwent sympathectomy, arterial bypass, or venous arterialization. Pain improvement, wound healing, and new ulcerations were primary outcome measures. Primary patency rates and limb salvage data were also collected as primary outcome measures in the bypass and arterialization study arms.

Results:

For sympathectomy, arterial bypass, and venous arterialization, pain relief was achieved in 89, 100, and 100 percent of patients, respectively; whereas wound healing occurred in 74, 93, and 75 percent, respectively. Postoperative ulcerations were 0, 3, and 8 percent, respectively. No secondary amputations were reported in these 33 studies. Complication rates were moderately high (2.1 to 30.8 percent).

Conclusion:

This systematic review confirms that sympathectomy, arterial bypass, and venous arterialization are efficacious treatments, and allows for an algorithmic approach to the surgical treatment of chronic hand ischemia.

CLINICAL QUESTION/LEVEL OF EVIDENCE:

Therapeutic, IV.
Correction of Pectus Excavatum by Custom-Made Silicone Implants: Contribution of Computer-Aided Design Reconstruction. A 20-Year Experience and 401 Cases
Authors: Chavoin Jean-Pierre , Grolleau Jean-Louis , Moreno Benjamin , Brunello Jérémie , André Aymeric , Dahan Marcel , Garrido Ignacio , Chaput Benoit
Published: April 2016

Background:

In the absence of demonstrable functional impairment, pectus excavatum is merely a congenital deformity, albeit with a marked psychological impact. Many patients do not wish to undergo thoracic remodeling operations, which are invasive and do not clearly result in respiratory or cardiac improvement.

Methods:

From 1993 to 2015, the authors designed 401 custom-made silicone implants to treat funnel chests. Before 2007, implants were made from plaster chest molds. Beginning in 2007, three-dimensional reconstructions were made from computed tomographic scans by computer-aided design. The authors prospectively recorded all assessments and follow-up data since 1993. Preoperative and postoperative photographs of two random groups of 50 patients were analyzed, in a blinded manner, by two surgeons independently. Intraoperative and postoperative complications, clinical outcomes, patient satisfaction, and quality of life were evaluated.

Results:

One infection and three hematomas were recorded. Periprosthetic seroma was evident in all cases. Patients rated the cosmetic outcomes of computer-aided design implants significantly higher than those of the earlier implants made using plaster molds (p = 0.030). Malformations were better corrected in the computer-aided design group (86 percent) than in the plaster group (72 percent) (p = 0.038). Patient satisfaction was higher in the former group (p = 0.011). Medical Outcomes Study 36-Item Short-Form Health Survey scores revealed significant improvements, both socially and emotionally.

Conclusions:

Correction of pectus excavatum using a computer-aided design silicone implant fulfils aesthetic and psychological demands. The technique is simple and reliable and yields high-quality results. In the medium term, the approach may render invasive techniques obsolete. These operations remain risky and of doubtful functional utility.

CLINICAL QUESTION/LEVEL OF EVIDENCE:

Therapeutic, III.