bluuebunny/crossref_metadata_2025 huggingface dataset:
Overtraining syndrome
Authors: Winsley Richard J
Published: April 2017

Prevalence rates of overreaching/overtraining syndrome in young athletes are ~30–35%, and burnout ~5–10%, indicating that a significant minority of young athletes are thus affected at some time during their sporting careers. Presenting symptoms vary considerably, most commonly including a sustained reduction or stagnation in performance, increased perception of effort during exercise, feelings of muscle heaviness, frequent upper respiratory tract infections, persistent muscle soreness, mood changes, sleep disturbance, and loss of appetite. Excessive training is not always the cause and both training and non-training stressors need to be considered as potential culprits. Power imbalances, single identity, early specialization, coach and/or parent pressure, conditional love, perfectionism, and entrapment may all help explain overtraining in childhood and adolescence. Screening and prevention strategies should take a holistic overview of the young athlete’s sporting environment in order that he/she continues to enjoy and develop in their chosen sport(s).
Epidemiology and prevention of sports injuries
Authors: Nauta Joske , van Mechelen Willem , Verhagen Evert ALM
Published: April 2017

Although sports injuries in children are common, prevention of these injuries is paramount. In order to set out effective prevention programmes, epidemiological studies need to be conducted on incidence, severity, and aetiology of sports injuries. Furthermore, the effectiveness of a preventive measure must be assessed, and the eventual implementation of a programme closely evaluated. When conducting epidemiological studies in sports injuries the injury definition used can have a large impact on the outcome, especially as the aetiology of sports injuries is highly multi-causal and recursive. In addition to distinguishing between ‘sports injury’, ‘sports injury incidence’ and ‘sports participation’, the severity of the injury must be defined by taking six indices into consideration: nature of sports injuries, duration and nature of treatment, sports time loss, working/school time loss, permanent damage, and costs of sports injuries.
Epidemiology and prevention of injuries in physical education
Authors: Collard Dorine CM , Nauta Joske , Backx Frank JG
Published: April 2017

Since physical education (PE) classes are often obligatory, the number of injuries sustained during physical education classes is high. The most frequently reported type of injury in PE classes changes as children grow older. Young children (under 12 years of age) most often injure their wrist and elbow, while the incidence of injuries in older children (over 12 years of age) is highest in the hand and ankle. PE classes containing activities like gymnastics and ball games result in the most damage, and PE teachers must play a key role in the prevention of PE-related injuries. PE teachers are responsible for creating a safe environment for sports and play, not only by ensuring that protective devices are used properly, but that equipment is in good order. They should also modify rules as well as screen their pupils for any physical limitations.
Epidemiology and prevention of injuries in competitive non-contact sports
Authors: Junior Luiz Carlos Hespanhol , Barboza Saulo Delfino , Mahler Per Bo
Published: April 2017

This chapter discusses the aetiology and prevention of paediatric sports injuries in non-contact sports, and the chapter covers bicycling, dance, gymnastics, running, skiing, snowboarding, swimming, tennis, badminton, and volleyball, which were selected based on their worldwide popularity. Each sport is covered in a systematic manner including a brief introduction of the sport practise, the epidemiology and aetiology of sport-specific injuries, risk factors, and preventive strategies. Because of similarities, skiing and snowboarding are grouped and discussed together, as are tennis and badminton. The knowledge summarized should be implemented in real-life situations in order to encourage children and adolescents to participate in sports where they will experience the well-known health benefits of sports participation, but with the lowest risk possible.
Dietary supplements
Authors: Maughan Ronald J , Shirreffs Susan M
Published: April 2017

The oral consumption of nutrition/dietary supplements is widespread in the general population and among sports people, both children and adults. Despite this, there is very little research on any aspect of dietary supplement consumption in child/youth athletes and translation of information from adult populations should be undertaken with great caution. Ethical considerations around the use of dietary supplements by child athletes are the same as those for the adult population, with the additional aspect of consideration of effects on growth and development. In spite of their popularity, it is likely that only a very small number of dietary supplements will have a beneficial effect on performance for child athletes who have no underlying nutritional deficiencies. Against this must be weighed the potential negative effects on health and performance and the possibility of inadvertent ingestion of a doping agent.
Doping and anti-doping
Authors: Vernec Alan , Gerrard David
Published: April 2017

Doping in sport, with its connotations of unethical behaviour and harm to health, has existed since antiquity. In contemporary times, an acceleration of doping practices resulted in the eventual development of a robust legal and scientific framework now entrenched in the World Anti-Doping Code. Young athletes are not immune to the myriad pressures to excel that exist in high-level sport. Many of these athletes are subject to Anti-Doping regulations and therefore they (and their physicians) must be familiar with Anti-Doping procedures and processes, including the Prohibited List and Therapeutic Use Exemptions. Advances in analytical and non-analytical techniques and strategies have increased detection and accountability. As part of the athletic team, physicians are in a unique position to recognize vulnerabilities and signs of doping behaviour. This must enable them to positively impact the course of a young athlete’s trajectory in life.
Cancer chemotherapy and radiation therapy
Authors: Chabner Bruce A. , Loeffler Jay
Published: April 2017

The last two decades have brought significant improvements in cancer therapy: patients with previously fatal diseases, including acute leukaemia, non-Hodgkin’s lymphoma, Hodgkin’s disease, and germ cell tumours, now have a high expectation of cure. For patients with the more common solid tumours, including lung, colon, and breast cancer, new chemotherapeutic and hormonal agents, molecularly targeted drugs, and monoclonal antibodies have improved treatment of both early and late stage disease and have extended survival. Nevertheless, cancer remains the second leading cause of death in the Western world, and nearly one third of patients diagnosed with cancer will die of their disease....
Nosocomial infections
Authors: Bowler I.C.J.W.
Published: April 2017

Hospital-acquired or nosocomial infections—defined for epidemiological studies as infections manifesting more than 48 hours after admission—are common. They affect 1.4 million people worldwide at any one time and involve between 5 and 25% of patients admitted to hospital, with considerable associated morbidity, mortality, and cost.

Clinical features—the most common sites of nosocomial infection are the urinary tract, surgical wounds, and the lower respiratory tract. Bacteria are the most important causes, including ...
Meningococcal infections
Authors: Brandtzaeg Petter
Published: April 2017

Neisseria meningitidis is an obligate human Gram-negative diplococcus. It is carried in the nasopharynx by about 10% of people, with most strains being harmless and inducing immunity. Pathogenic strains usually belong to specific clones that are encapsulated, express pili and the major porin, PorA. Serogroups A, B, and C usually account for more than 90% of all invasive isolates....
Leprosy (Hansen’s disease)
Authors: Lockwood Diana N.J.
Published: April 2017

Leprosy is a chronic granulomatous disease caused by Mycobacterium leprae, an acid-fast intracellular organism not yet cultivated in vitro. It is an important public health problem worldwide, with an estimated 4 million people disabled by the disease. Transmission of M. leprae is only partially understood, but untreated lepromatous patients discharge abundant organisms from their nasal mucosa into the environment....
Syphilis
Authors: Donovan Basil , Read Phillip
Published: April 2017

Syphilis results from infection with the spirochaete Treponema pallidum subsp. pallidum, for which humans are the only known natural host. In adults it is transmitted primarily by sexual contact. The organism gains entry into the body through small breaks in the skin or the intact mucosal surfaces of the genitals, mouth, or anus, and is able to invade and survive in a wide variety of tissues....
The inborn errors of metabolism: general aspects
Authors: Watts Richard W.E. , Cox T.M.
Published: April 2017

Historical perspective—inborn errors of metabolism were first recognized by Archibald Garrod, whose studies illustrated the dynamic aspects of human biochemistry and how unitary hereditary factors caused variation in the turnover of physiological metabolites derived from dietary components. He proposed that the activity of enzymes involved in human metabolism (e.g. of tyrosine degradation) were subject to control by specific genes, and several of the disorders studied by him were subsequently shown to be the result of block at some point in normal metabolism. He also noted the importance of consanguinity in the clinical expression of rare genetic variants which behave as recessive human disease traits....
Inborn errors of fructose metabolism
Authors: Cox T.M.
Published: April 2017

Most people in developed countries ingest 50 to 150 g fructose equivalents daily in their diet and the use of this sugar in food and drinks is increasing globally. Fructose is absorbed rapidly by a carrier mechanism that facilitates transport across the intestinal epithelium, metabolized (mainly in the liver) by the enzymes ketohexokinase (fructokinase), aldolase B, and triokinase, and eventually converted into glucose or glycogen. Dietary sugar has particular effects on those whose capacity to metabolise fructose is limited. Fructose occurs either as a free monosaccharide, as a component of sucrose, a disaccharide from which it is released by digestion; fructose may also be derived from the metabolism of the sugar alcohol, sorbitol....
Jaundice
Authors: Thompson Richard
Published: April 2017

All haem molecules are degraded in macrophages by haem oxygenase to biliverdin, and thence by biliverdin reductase to bilirubin, which is selectively removed by hepatocytes from sinusoidal blood and then conjugated, mainly by one of the two specific isoforms of the microsomal enzyme UDP-glucuronyl (glucuronate-glucuronosyl) transferase, chiefly with two glucuronic acid moieties. Conjugated bilirubin is excreted into the bile by the anionic conjugate transporter protein (MRP2), but in many liver diseases it refluxes back into blood and—since it is water soluble and less firmly bound to albumin than unconjugated bilirubin—about 1% is filtered across the glomerular membrane and darkens the urine (choluria). In the distal intestine conjugated bilirubin is deconjugated and reduced to a series of uro- and stercobilinogens that give the normal colour to faeces. Some colourless urobilinogen is normally absorbed from the colon and undergoes an enterohepatic circulation, with a small amount being excreted in urine. If this biliary excretion is impaired in liver disease, or increased in haemolysis, then excess urobilinogen is excreted in urine, where it is easily detected by routine clinical ‘stix’....
Primary sclerosing cholangitis
Authors: Chapman R.W. , Williamson K.D.
Published: April 2017

Case History—A 60 yr old woman, known to have long standing colitis, now presenting with abdominal pain and weight loss.

Primary sclerosing cholangitis is a chronic cholestatic liver disease caused by diffuse inflammation and fibrosis that can involve the entire biliary tree. The cause is unknown, but presumed to be immune mediated, and there is a very close association with inflammatory bowel disease, particularly ulcerative colitis....
Chronic pancreatitis
Authors: Schatz Richard A. , Toskes Phillip P.
Published: April 2017

Chronic pancreatitis is most commonly due to chronic alcoholism in adults and cystic fibrosis in children, but there are many other causes/associations. Typical presentation is with (1) abdominal pain—but this is not always a feature and when present can vary from being mild to extremely severe; and/or (2) maldigestion—diarrhoea/steatorrhoea and weight loss....
Cardiac physiology
Authors: Evans Rhys , MacLeod Kenneth T. , Marston Steven B. , Severs Nicholas J. , Sugden Peter H.
Published: April 2017

The function of the heart is to provide the tissues of the body with sufficient oxygenated blood and metabolites to meet the moment-to-moment needs as dictated by physical activity and postural and emotional changes.

Cardiac myocytes are the contractile cells of the heart and constitute the bulk of heart mass. There are differences between the myocytes of the ventricles, the atria, and the conduction system: ventricular myocytes are elongated cells, packed with myofibrils (the contractile apparatus) and mitochondria (for ATP production). Myofibrils are repeating units (sarcomeres) made up of thin actin filaments anchored at the Z-discs at either end of the sarcomere, and thick myosin filaments which interdigitate and interact with the thin filaments. Contraction results from sarcomere shortening produced by the ATP-dependent movement of the thin and thick filaments relative to one another. Transverse (T-) tubules facilitate extracellular Ca...
Echocardiography
Authors: Banning Adrian P. , Mitchell Andrew R.J. , Newton James D.
Published: April 2017

For video material relating to echocardiography, please go to Echocardiography Videos.

Ease of use, rapid data provision, portability, and safety mean that echocardiography has become the principal investigation for almost all cardiac conditions. A modern transthoracic echocardiography examination combines real-time two-dimensional (2D) imaging of the myocardium and valves with information about velocity and direction of blood flow obtained by Doppler and colour-flow mapping. A complete examination can be performed in most patients in less than 30 min....
Management of acute coronary syndrome
Authors: Fox Keith A.A. , Kharbanda Rajesh K.
Published: April 2017

The acute coronary syndrome (ACS) is precipitated by an abrupt change in an atheromatous plaque, resulting in increased obstruction to perfusion and ischaemia or infarction in the territory supplied by the affected vessel. The clinical consequences of plaque rupture can range from an entirely silent episode, through to unstable symptoms of ischaemia without infarction, to profound ischaemia complicated by progressive infarction, heart failure, and risk of sudden death. Clinical presentation with an ACS identifies a patient at high risk of further cardiovascular events requiring a defined acute and long-term management strategy....
Therapeutic anticoagulation
Authors: Keeling David
Published: April 2017

Low molecular weight heparins (LMWH) have largely replaced unfractionated heparin. Their much more predictable anticoagulant response combined with high bioavailability after subcutaneous injection means that the dose can be calculated by body weight and given subcutaneously without any monitoring or dose adjustment. Their widespread use resulted in most patients with deep vein thrombosis being managed as outpatients, and this is also increasingly the case for uncomplicated pulmonary embolism....
Essential hypertension—definition, epidemiology, and pathophysiology
Authors: Williams Bryan
Published: April 2017

‘Essential hypertension’ is high blood pressure for which there is no clearly defined aetiology. From a practical perspective, it is best defined as that level of blood pressure at which treatment to lower blood pressure results in significant clinical benefit—a level which will vary from patient to patient depending on their absolute cardiovascular risk....
Idiopathic oedema of women
Authors: Firth John D.
Published: April 2017

Idiopathic oedema is an unsatisfactory label that is applied to women who complain of swelling, typically variable, with diagnosis requiring exclusion of known causes of oedema and (most authors would agree) demonstration of weight gain, from morning to evening, of more than 1.4 kg.

The cause of idiopathic oedema is (by definition) unknown: hypotheses include abnormal capillary permeability/leakage, re-feeding oedema, and diuretic-induced oedema. There is no clear relationship to the menstrual cycle. Even if not a primary cause, the use and abuse of diuretics can complicate and exacerbate the problem....
Cardiorenal syndrome
Authors: Green Darren , Kalra Philip A
Published: April 2017

Concurrent renal and cardiovascular disease is common. Renal disease is a potent cardiovascular risk factor and consequently cardiovascular disease is the most important cause of mortality in patients with endstage renal disease. This increased risk is mediated by vascular disease (coronary calcification, endothelial dysfunction, dyslipidaemia, etc.), left ventricular hypertrophy, risk of arrhythmias and left ventricular systolic and diastolic dysfunction. These interactions are further complicated by the presence of anaemia in advanced renal disease.
The coexistence of renal disease and heart failure presents a major therapeutic challenge and requires careful attention to fluid status and renal function. Diuretic resistance is common and the important prognostic benefit of angiotensin converting enzyme (ACE) inhibition in this high-risk group is often neglected. Cardiovascular drugs, in particular antiarrhythmic agents such as digoxin, sotalol, and flecainide, should be used with caution in patients with renal disease. Patients with severe cardiac and renal disease require a multidisciplinary approach to their management.
Acute respiratory failure
Authors: Leaver Susannah , Evans Timothy
Published: April 2017

Acute respiratory failure is defined clinically by hypoxaemia (PaO2 <8 kPa, normal range 10–13.3 kPa) with (type 2) or without (type 1) hypercapnia (PaCO2 >6.5 kPa). It is one of the most common problems afflicting the severely ill patient and often necessitates intensive care unit admission....
Inherited defects of connective tissue: Ehlers–Danlos syndrome, Marfan’s syndrome, and pseudoxanthoma elasticum
Authors: Burrows N.P.
Published: April 2017

The inherited disorders of connective tissue are all conditions in which structural defects in collagen or other extra cellular matrix proteins lead to its fragility, with the commonest sites of involvement being the skin, ligaments and vasculature.

EDS is a heterogeneous group of disorders resulting from abnormalities in collagen synthesis and processing, or of other extracellular matrix proteins. They can be classified on the basis of descriptive clinical phenotype and/or underlying molecular cause. Most cases are autosomal dominant, but 30 to 50% may be sporadic....
Osteonecrosis, osteochondrosis, and osteochondritis dissecans
Authors: Clunie Gavin , O’Gradaigh Donncha , Crisp Adrian
Published: April 2017

Osteonecrosis (‘bone death’) can be caused by a range of conditions including trauma, drugs (e.g. glucocorticoids), metabolic or endocrine conditions (e.g. Cushing’s syndrome, Gaucher disease), and haematological disease (e.g. sickle cell disease, antiphospholipid syndrome [APLS]). There are no specific features on history or examination but the condition may present with pain or localised skeletal failure. Diagnosis is made by Magnetic Resonance (MR) imaging. Treatment involves approaches designed to improve blood supply (vasodilators, low-molecular-weight heparin), promote bone repair (bisphosphonates), revascularize bone (e.g. surgical core decompression), or remove or replace tissue (e.g. osteotomy, arthroplasty)....
Thin membrane nephropathy
Authors: Topham Peter , Feehally John
Published: April 2017

Thin membrane nephropathy is a common autosomal dominant glomerular disorder that results in persistent non-visible haematuria and is pathologically characterized by the presence of diffuse and uniform thinning of the glomerular basement membrane. Recent genetic studies have identified mutations in the COL4A3 and COL4A4 genes in 40% of affected families. There is no specific treatment. Prognosis is excellent for most people, but a few cases with progressive renal impairment have been described....
Malignancy-associated renal disease
Authors: Neil Turner A
Published: April 2017

Malignancies can affect the kidneys by direct invasion, metabolic and remote effects of tumour products, deposition of tumour products, triggering of immune reactions, and effects of treatment.

Particular malignancy-associated renal diseases include:

1 Thrombotic microangiopathy—particularly reported for malignancies of the stomach, pancreas, and prostate, and also with certain chemotherapeutic agents....
Atherosclerotic renovascular disease
Authors: Kalra P A , Firth J D
Published: April 2017

Atherosclerotic renovascular disease (ARVD) refers to atheromatous narrowing of one or both renal arteries and frequently co-exists with atherosclerotic disease in other vascular beds. Patients with this condition are at high risk of adverse cardiovascular events, with mortality around 8% per year. Many patients with ARVD have chronic kidney disease, but only a minority progress to end-stage kidney disease (ESKD), suggesting that pre-existing hypertensive and/or ischaemic renal parenchymal injury is the usual cause of renal dysfunction. Many patients with ARVD are asymptomatic, but there can be important complications such as uncontrolled hypertension, rapid decline in kidney function and recurrent acute heart failure (flash pulmonary oedema)....
Renal diseases in the tropics
Authors: Jha Vivekanand
Published: April 2017

Kidney diseases encountered in tropical areas are a mix of conditions that have worldwide distribution and those that are secondary to factors unique to the tropics, e.g. climatic conditions, infectious agents, nephrotoxic plants, envenomations, and chemical toxins. Important presentations are with nephrotic syndrome, acute kidney injury (AKI), and progressive renal insufficiency. In addition to the climate, cultural factors, illiteracy, superstitions, living conditions, level of access to health care, and nutritional status also affect the nature and course of disease. Knowledge of such conditions and issues is important for medical professionals in all parts of the globe, as ease of travel means that individuals and practices are exported with increasing frequency....
Primary myelofibrosis
Authors: Spivak Jerry L.
Published: April 2017

Myelofibrosis is a reactive process common to many malignant and benign disorders. Primary myelofibrosis is a chronic myeloproliferative disorder of unknown aetiology that involves a multipotent haemopoietic progenitor cell and results in abnormalities in red cell, white cell, and platelet production in association with marrow fibrosis and extramedullary haemopoiesis....
Myeloma and paraproteinaemias
Authors: Kyle Robert A. , Vincent Rajkumar S.
Published: April 2017

The paraproteinaemias are a group of neoplastic (or potentially neoplastic) diseases associated with the proliferation of a single clone of immunoglobulin-secreting plasma cells.

This asymptomatic condition of unknown cause is characterized by a serum paraprotein concentration under 30 g/l, less than 10% monoclonal plasma cells in the bone marrow, and no evidence of end-organ damage (CRAB) hypercalcaemia, renal insufficiency, anemia, and bone lesions related to the plasma cell proliferative process....
Erythropoiesis and the normal red cell
Authors: Rita Migliaccio Anna , Papayannopoulou Thalia
Published: April 2017

Erythropoiesis is a highly regulated, multistep process in which stem cells, after a series of amplification divisions, generate multipotential progenitor cells, then oligo- and finally unilineage erythroid progenitors, and then morphologically recognizable erythroid precursors and mature red cells.

Ontogeny of erythropoiesis—this involves a series of well-coordinated events during embryonic and early fetal life: (1) embryo—the fetal yolk sac makes embryonic haemoglobins; (2) fetus—the main site of erythopoiesis is the liver, which initially produces mainly fetal haemoglobin (Hb F, ...
Structure and function of skin
Authors: McGrath John A.
Published: April 2017

Skin provides a mechanical barrier against the external environment, but has further roles in thermoregulation, metabolism, and the regulation of fluid balance, as well as being socially important in contributing to physical and chemical attraction between individuals.

There are more than 1000 different skin diseases, although relatively few are commonly encountered in general medical practice. However, several skin conditions can reflect a general medical problem such as a systemic infection, or a cutaneous manifestation of internal disease (e.g. patients with underlying malignancy, endocrine disorders or chronic inflammatory diseases). An understanding of skin structure and function is also important in dealing with the common clinical scenario of ‘skin failure’ resulting from adverse drug reactions, burns, or extensive trauma....
Tumours of the skin
Authors: O’Toole Edel
Published: April 2017

A wide range of tumours, both benign and malignant, are found in skin. Benign skin lesions such as seborrhoeic keratoses and skin tags are often just a cosmetic nuisance, but some benign skin lesions can be a component of diseases with serious medical consequences, e.g. neurofibromatosis or LEOPARD syndrome....
Parkinsonism and other extrapyramidal diseases
Authors: Ray Chaudhuri K.
Published: April 2017

For video material relating to movement disorders, please go to Movement Disorders Videos.

Parkinson’s disease affects about 0.2% of the population, including 2% of those over 80 years of age. The main pathological feature is degeneration of neuromelanin-containing neurons in the pars compacta of the substantia nigra, which leads directly and indirectly to excessive inhibition of the thalamus and consequent bradikinesia....
Movement disorders other than Parkinson’s disease
Authors: Barker Roger A. , Burn David J.
Published: April 2017

For video material relating to movement disorders, please go to Movement Disorders Videos.

Movement disorders are considered in five main categories—dystonia, chorea, tremor, tics, and myoclonus. Each disorder may occur in several diseases, and each may be the sole manifestation of a given neurological disease, but they also may only represent a component of a more widespread disorder....
Headache
Authors: Goadsby Peter J.
Published: April 2017

Headache is among the most common of human maladies. So much so that it is generally (and often incorrectly) assumed to be understood, especially by doctors. The classification of headache, with formal definitions of different diagnostic entities, by the International Headache Society into (1) primary—occurring in the absence of external causes, and (2) secondary—some of which may have sinister cause, has greatly simplified the description, understanding, and management of this often challenging symptom. It also allows those headaches with serious or life-threatening consequences to be distinguished from other forms....
Psychopharmacology in medical practice
Authors: Cowen Philip J.
Published: April 2017

Psychotropic drugs play an indispensable role in the treatment of severe psychiatric illness such as schizophrenia and bipolar disorder. They are often used to treat other conditions, particularly depression and anxiety disorders, but for these disorders nondrug treatments are effective and—if available—are often preferred by patients....
Central nervous system physiology in anaesthetic practice
Authors: Adapa Ram , Absalom Anthony
Published: April 2017

How and where consciousness is generated and maintained remains an unsolved scientific mystery, and this has impeded progress in understanding anaesthesia. In recent years, however, significant progress has been made in understanding the neurobiology of anaesthetic-induced loss of consciousness. This has been made possible by advances in molecular biology techniques, which have helped shed light on the molecular mechanisms of action of the anaesthetic agents. In parallel, the development of neuroimaging techniques, such as functional magnetic resonance imaging and positron emission tomography, has also provided an enormous impetus. These techniques are providing new insights into the neural correlates of consciousness, and new insights into the alterations in neurophysiology associated with impaired consciousness caused by sleep, sedation, and anaesthesia. The information being gained from these studies on the neurobiology of impairments of attention, awareness, and memory will hopefully eventually not only lead to improvements in our understanding of consciousness and anaesthesia, but also to better clinical care. Understanding of memory functions during sedation and anaesthesia may, for example, lead to better strategies for preventing awareness with subsequent explicit recall of intraoperative events. Further, a better understanding of the neurobiology of anaesthetic-induced unconsciousness may inform future development of better anaesthetic agents, with a broader therapeutic index, and fewer unwanted effects.
Chemical reaction networks for computing logarithm
Authors: Chou Chun Tung
Published: April 2017

Living cells constantly process information from their living environment. It has recently been shown that a number of cell signaling mechanisms (e.g. G protein-coupled receptor and epidermal growth factor) can be interpreted as computing the logarithm of the ligand concentration. This suggests that logarithm is a fundamental computation primitive in cells. There is also an increasing interest in the synthetic biology community to implement analog computation and computing the logarithm is one such example. The aim of this article is to study how the computation of logarithm can be realized using chemical reaction networks (CRNs). CRNs cannot compute logarithm exactly. A standard method is to use power series or rational function approximation to compute logarithm approximately. Although CRNs can realize these polynomial or rational function computations in a straightforward manner, the issue is that in order to be able to compute logarithm accurately over a large input range, it is necessary to use high-order approximation that results in CRNs with a large number of reactions. This article proposes a novel method to compute logarithm accurately in CRNs while keeping the number of reactions in CRNs low. The proposed method can create CRNs that can compute logarithm to different levels of accuracy by adjusting two design parameters. In this article, we present the chemical reactions required to realize the CRNs for computing logarithm. The key contribution of this article is a novel method to create CRNs that can compute logarithm accurately over a wide input range using only a small number of chemical reactions.
Physicochemical Characterization of Different Varieties of Quinoa
Authors: Aluwi Nicole A. , Murphy Kevin M. , Ganjyal Girish M.
Published: April 2017

Quinoa is a pseudocereal from South America known for its unique nutritional properties. Hundreds of varieties and experimental lines are currently either grown or in development in many countries around the world. There exists a lack of information about, and understanding of, the nutritional composition and processing characteristics of these varieties and their potential end‐use applications. Twenty‐eight quinoa varieties and experimental lines tested in the Washington State University breeding program were evaluated for their chemical composition and physicochemical characteristics. Both compositional and physicochemical analysis demonstrated wide variation in properties among the varieties. Analysis of flour swelling power, water absorption index, and differential scanning calorimetry further supported the differences hypothesized between varieties. Hierarchical cluster analysis grouped the varieties into four clusters. Principal component analysis was used to visually display the data on a biplot, representing most of the variance (>60%) in the set. These results reflect possible end uses in bread, cakes, and noodles for varieties exhibiting high viscosities.
Pathogenic Variability of Meloidogyne incognita Populations Occurring in Pepper-Production Greenhouses in Israel Toward Me1, Me3 and N Pepper Resistance Genes
Authors: Bucki Patricia , Paran Ilan , Ozalvo Rachel , Iberkleid Ionit , Ganot Liana , Braun Miyara Sigal
Published: April 2017

Natural variation in the root-knot nematode Meloidogyne incognita is problematic for breeding programs: populations possessing similar morphological characteristics can produce different reactions on the same host. We collected 30 widely dispersed M. incognita populations from protected pepper production systems in major pepper-growing regions of Israel and accurately identified their virulence characteristics by modified differential host test in a growth chamber on tomato, tobacco, cotton, melon, pepper, and peanut. Galling indices and reproduction were determined on the different hosts. All populations fit the published scheme for M. incognita race 2, except for reproduction on cotton plants by five out of 25 tested M. incognita populations, indicating host-range variations. Reaction of three genes that confer resistance to M. incognita—Me1, Me3 and N—to the collected populations was evaluated. Several M. incognita populations induced galling and reproduced successfully on pepper genotypes carrying Me3 and N, whereas plant resistance conferred by Me1 was more robust for all examined populations. Moreover, the effect of genetic background on Me1 resistance demonstrated a relative advantage of several genotypes in nematode infestations. Efficiency of Me3 under local nematode infestation was further studied with a homozygous line carrying two Me3 alleles. Reproduction of virulent populations on the homozygotes (Me3/Me3) and heterozygotes (Me3/Me3+) was similar, suggesting a limited quantitative effect of Me3. These results present the first characterization of host range, reproduction, and molecular aspects of M. incognita from Israel and highlight the importance of taking a multidimensional approach in pepper-breeding programs for resistance to M. incognita.
Together into the future...Pharmacogenomics and documentation
Authors: McCormick Kathleen A.
Published: April 2017

New partnerships target optimal care quality and outcomes
Cerclage Wiring Through a Mini-Open Approach to Assist Reduction of Subtrochanteric Fractures Treated With Cephalomedullary Fixation: Surgical Technique
Authors: Codesido Pablo , Mejía Ana , Riego Jonathan , Ojeda-Thies Cristina
Published: April 2017

Despite advances in the management of subtrochanteric fractures, in particular with the use of cephalomedullary nails, outcomes remain worse than other fractures of the proximal femur. Because an anatomic reduction is needed to offer the best results, several methods of reduction, using clamps and wires have been described. Reduction of fractures in elderly patients is especially complicated because of poor bone quality, comorbidities, and unfavorable fracture patterns. We describe a new technique of reduction and cerclage wiring through a mini-open approach for isolated subtrochanteric, as well as intertrochanteric fractures with extension into the subtrochanteric area, and report our results in a series of patients.
Smoking, Quitting, and the Provision of Smoking Cessation Support: A Survey of Orthopaedic Trauma Patients
Authors: McCrabb Sam , Baker Amanda L. , Attia John , Balogh Zsolt J. , Lott Natalie , Palazzi Kerrin , Naylor Justine , Harris Ian A. , Doran Christopher M. , George Johnson , Wolfenden Luke , Skelton Eliza , Bonevski Billie
Published: April 2017

Objective:

This study investigates orthopaedic trauma patients smoking cessation history, intentions to quit, receipt of smoking cessation care during hospital admission, and patient-related factors associated with receipt of smoking cessation care.

Methods:

An online cross-sectional survey of orthopaedic trauma patients was conducted in 2 public hospitals in New South Wales, Australia. Prevalence of smoking and associated variables were described. Logistic regressions were used to examine whether patient characteristics were associated with receipt of smoking cessation care.

Results:

Eight hundred nineteen patients (response rate 73%) participated. More than 1 in 5 patients (21.8%) were current smokers (n = 175). Of the current smokers, more than half (55.3%) indicated making a quit attempt in the last 12 months and the majority (77.6%) were interested in quitting. More than a third of smokers (37.4%) were not advised to quit; 44.3% did not receive any form of nicotine replacement therapy; and 24.1% reported that they did not receive any of these 3 forms of smoking cessation care during their admission. Provision of care was not related to patient characteristics.

Conclusions:

The prevalence of smoking among the sample was high. Respondents were interested in quitting; however, the provision of care during admission was low. Smoking cessation interventions need to be developed to increase the provision of care and to promote quit attempts in this Australian population.

Level of Evidence:

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.
Time From Injury to Surgical Fixation of Diaphyseal Humerus Fractures Is Not Associated With an Increased Risk of Iatrogenic Radial Nerve Palsy
Authors: Shoji Kristin , Heng Marilyn , Harris Mitchel B. , Appleton Paul T. , Vrahas Mark S. , Weaver Michael J.
Published: April 2017

Objectives:

To determine whether time from injury to fixation of diaphyseal humeral fractures and nonunions is associated with the risk of iatrogenic radial nerve palsy.

Design:

Retrospective review.

Setting:

Two Level 1 trauma centers.

Patients/Participants:

Between 2001 and 2015, 325 patients who had documented intact radial nerve function preoperatively were treated with fixation of a humerus fracture or humerus nonunion.

Intervention:

Open reduction and internal fixation.

Main Outcome Measurements:

Development of an iatrogenic radial nerve injury. Those with an injury were followed to either resolution of the nerve palsy or definitive treatment.

Results:

The risk of iatrogenic radial nerve palsy was 7.7% (25/325). Time to surgery was not significantly associated with iatrogenic radial nerve palsy. In a multiple variable analysis, when comparing patients treated within 4 weeks to those treated 4–8 weeks (P = 0.41), 8–12 weeks (P = 0.94), and over 12 weeks (0.20), there were no significant associations. Independent risk factors for iatrogenic radial nerve palsy included distal location of fracture (P = 0.04, odds ratio 3.71) and previous fixation (P = 0.03, odds ratio 3.80). Of the 25 iatrogenic nerve injuries, 22 recovered fully with expectant management, 1 was lost to follow-up, and 2 required either nerve graft or tendon transfers.

Conclusions:

Time from injury to surgery does not seem to be a risk factor for developing an iatrogenic radial nerve palsy when treating diaphyseal humerus fractures. Patients with distal fractures, and those with previous fracture implants, are at increased risk of iatrogenic radial nerve palsy.

Level of Evidence:

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.
Sunitinib Induces NK-κB-dependent NKG2D Ligand Expression in Nasopharyngeal Carcinoma and Hepatoma Cells
Authors: Huang Yu-xian , Chen Xin-tong , Guo Kun-yuan , Li Yu-hua , Wu Bing-yi , Song Chao-yang , He Yan-jie
Published: April 2017

Multitargeted tyrosine kinase inhibitors (MTKIs) have been shown to combine with natural killer (NK) cell adoptive transfer for the treatment in various cancers. MTKIs sensitize cancer cells to NK cell therapy through upregulation of nature killer group 2 member D ligands (NKG2DLs) on tumor cells. However, the molecular mechanism of MTKIs-mediated upregulation of NKG2DLs is still unknown. In this study, we confirmed sunitinib induced downregulation of its targets, such as vascular endothelial growth factor, platelet-derived growth factor, and c-kit in multiple-drug–resistant nasopharyngeal carcinoma cell line CNE2/DDP and hepatoma cell line HepG2. Then, we further showed sunitinib induced cell proliferation inhibition, apoptosis, and DNA damage in CNE2/DDP and HepG2 cells. Coculture experiments showed that sunitinib-treated CNE2/DDP and HepG2 cells were able to increase the activation and cytotoxicity of NK cells. Quantitative polymerase chain reaction results showed that sunitinib upregulated NKG2DLs, apoptotic genes, DNA damage repair genes, and nuclear factor (NF)-κβ family genes. Silencing of NF-κβ1, NF-κβ2, or RelB (NF-κβ pathway) inhibited sunitinib-induced upregulation of NKG2DLs. Taken together, we concluded that sunitinib upregulated NKG2DLs through NF-κβ signaling noncanonical pathway which might mediate higher cytotoxic sensitivity of CNE2/DDP and HepG2 cells to NK cells.
HEALTH CONDITIONS LINKED TO AGE-RELATED MACULAR DEGENERATION ASSOCIATED WITH DARK ADAPTATION
Authors: Laíns Inês , Miller John B. , Mukai Ryo , Mach Steven , Vavvas Demetrios , Kim Ivana K. , Miller Joan W. , Husain Deeba
Published: April 2017

Purpose:

To determine the association between dark adaption (DA) and different health conditions linked with age-related macular degeneration (AMD).

Methods:

Cross-sectional study, including patients with AMD and a control group. Age-related macular degeneration was graded according to the Age-Related Eye Disease Study (AREDS) classification. We obtained data on medical history, medications, and lifestyle. Dark adaption was assessed with the extended protocol (20 minutes) of AdaptDx (MacuLogix). For analyses, the right eye or the eye with more advanced AMD was selected. Multivariate linear and logistic regressions were performed, accounting for age and AMD stage.

Results:

Seventy-eight subjects (75.6% AMD; 24.4% controls) were included. Multivariate assessments revealed that body mass index (BMI; β = 0.30, P = 0.045), taking AREDS vitamins (β = 5.51, P < 0.001), and family history of AMD (β = 2.68, P = 0.039) were significantly associated with worse rod intercept times. Abnormal DA (rod intercept time ≥ 6.5 minutes) was significantly associated with family history of AMD (β = 1.84, P = 0.006), taking AREDS supplements (β = 1.67, P = 0.021) and alcohol intake (β = 0.07, P = 0.017).

Conclusion:

Besides age and AMD stage, a higher body mass index, higher alcohol intake, and a family history of AMD seem to impair DA. In this cohort, the use of AREDS vitamins was also statistically linked with impaired DA, most likely because of an increased severity of disease in subjects taking them.
Shoulder Dynamic Control Ratio and Rotation Range of Motion in Female Junior Elite Handball Players and Controls
Authors: van Cingel Robert , Habets Bas , Willemsen Linn , Staal Bart
Published: April 2017

Objective:

To compare glenohumeral range of motion and shoulder rotator muscle strength in healthy female junior elite handball players and controls.

Design:

Cross-sectional case–control study.

Setting:

Sports medical center.

Participants:

Forty elite female handball players and 30 controls active in nonoverhead sports participated in this study.

Main Outcome Measures:

Passive external rotator (ER), internal rotator (IR), and total range of motion (TROM) of the dominant and nondominant arm were examined with a goniometer. An isokinetic dynamometer was used to evaluate concentric and eccentric rotator muscle strength at 60 and 120 degrees/s with dynamic control ratio (DCR = ERecc:IRcon) as the main outcome parameter.

Results:

Except for the ER range of motion in the nondominant arm, no significant differences were found between groups for IR, ER of the dominant arm, and the TROM. Within the handball group, the side-to-side difference for IR of the dominant arm was −1.4 degrees. The ER and the TROM of the dominant arm were significantly larger, 6.3 and 4.9 degrees, respectively. For both groups, the DCR values were above 1 and no significant differences were found between the dominant and nondominant arm. The DCR values in the handball group were significantly lower than in the control group.

Conclusions:

Based on the adopted definitions for muscle imbalance, glenohumeral internal range of motion deficit and TROM deficit our elite female handball players seem not at risk for shoulder injuries. Prospective studies are needed to support the belief that a DCR below 1 places the shoulder at risk for injury.
Telephone Encounters Predict Future High Financial Expenditures in Inflammatory Bowel Disease Patients
Authors: Click Benjamin , Anderson Alyce M. , Ramos Rivers Claudia , Koutroubakis Ioannis E. , Hashash Jana G. , Dunn Michael A. , Schwartz Marc , Swoger Jason , Barrie Arthur , Szigethy Eva , Regueiro Miguel , Schoen Robert E. , Binion David G.
Published: April 2017

Background:

Telephone activity is essential in management of complex chronic diseases including inflammatory bowel disease (IBD). Telephone encounters logged in the electronic medical record have recently been proposed as a surrogate marker of disease activity and impending health care utilization; however, the association between telephone calls and financial expenditures has not been evaluated.

Study:

We performed a 3-year prospective observational study of telephone encounters logged at a tertiary referral IBD center. We analyzed patient demographics, disease characteristics, comorbidities, clinical activity, and health care financial charges by telephone encounter frequency.

Results:

Eight hundred one patients met inclusion criteria (52.3% female; mean age, 44.1 y), accounted for 12,669 telephone encounters, and accrued $70,513,449 in charges over 3 years. High telephone encounter frequency was associated with female gender (P=0.003), anxiety/depression (P<0.001), and prior IBD surgery (P<0.001). High telephone encounter categories had significantly more hospitalizations (P<0.001), IBD surgery (P<0.001), worse quality of life (P<0.001), more corticosteroid (P<0.001), biological (P<0.001), and opiate prescriptions (P<0.001). High telephone encounter frequency patients amassed higher total available charges in each year (P<0.001) and over the 3 years (P<0.001). Telephone encounters in 2009 (P=0.02) and 2010 (P<0.001) were significantly associated with financial charges the following year after controlling for demographic, utilization, and medication covariates.

Conclusions:

Increased telephone encounters are associated with significantly higher health care utilization and financial expenditures. Increased call frequency is predictive of future health care spending. Telephone encounters are a useful tool to identify patients at risk of clinical deterioration and large financial expense.