bluuebunny/crossref_metadata_2025_split huggingface dataset:
Clostridium difficile
Authors: Eyre David W. , Wilcox Mark H. 
Published: February 2020

Abstract
Clostridium difficile (recently renamed as Clostridioides difficile) is a Gram-positive spore-forming anaerobic bacillus that is ubiquitous in nature, and particularly common in healthcare environments. Its spores are part of the colonic flora in about 2–3% of healthy adults, with colonization rates increasing, typically up to 10–20%, during hospitalization. Disease occurs when the organism shifts from quiescent spores to replicating vegetative cells with toxin (A and B) production; this happens when there is inhibition of the resident colonic flora (gut microbiome) by prescribed antibiotics, although cases can occur when no such precipitant is identified. C. difficile infection is now recognized as the most important bacterial enteric pathogen in wealthier countries, epidemics, and outbreaks of which are common, most notoriously now due to the ribotype 027 (NAP-1) strain that is associated with more severe disease and poor outcomes.
Nocardiosis
Authors: Hay Roderick J. 
Published: February 2020

Abstract
Nocardia species—Nocardia asteroides, N. brasiliensis, and N. otidiscaviarum—are Gram-positive, filamentous, partially acid-fast bacteria. They are occasionally detectable in environmental sources such as soil, but they rarely cause infections in humans, although they can give rise to a variety of different diseases. In healthy individuals, most commonly in the tropics, they can present with cutaneous abscesses or subcutaneous infections (actinomycetoma) in which the organisms are present as clusters of filaments or grains. In immunocompromised patients they cause a disseminated or localized deep infection, with particular sites affected being the lungs or brain. Diagnosis of Nocardia infection depends on culture, although histopathology is very useful in Nocardia actinomycetomasiii. Antibiotic treatment is typically with a sulphonamide (often as co-trimoxazole for lung infections), but combinations of drugs are usually given because the responsiveness of Nocardia species is very variable.
Syphilis
Authors: Read Phillip , Donovan Basil 
Published: February 2020

Abstract
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.
Since the availability of penicillin, syphilis has become primarily (&gt;90%) a disease of less affluent countries or of minority subpopulations in more affluent countries with poor access to healthcare. It is also a disease of people with rapid rates of partner change (e.g. men who have sex with men and commercial sex workers).
Rickettsioses
Authors: Griffiths Karolina , Eldin Carole , Raoult Didier , Parola Philippe 
Published: February 2020

Abstract
Rickettsioses are mild to life-threatening zoonoses caused by obligate intracellular bacteria of the order Rickettsiales (family Rickettsiaceae). Arthropods, including ticks, fleas, and mites, are implicated as their vectors, reservoirs, or amplifiers. With an increasing number of new pathogens and recognition of new pathogenicity and affected geographical areas over the past few decades, there is a better understanding of the scope and importance of these pathogens, particularly as a paradigm to understanding emerging and remerging infections. The taxonomy has undergone numerous changes, with now three main groups classified as rickettsioses according to morphological, antigenic and metabolic characteristics: (1) Rickettsioses due to the bacteria of the genus Rickettsia, including the spotted fever group, typhus groups (Rickettsiaceae), (2) Ehrlichioses and Anaplasmoses due to bacteria of the Anaplasmataceae and (3) scrub typhus due to Orientia tsutsugamushi.
Coxiella burnetii infections (Q fever)
Authors: Marrie Thomas J. 
Published: February 2020

Abstract
Q fever is a zoonosis caused by Coxiella burnetii, an intracellular Gram-negative spore-forming bacterium, the common animal reservoirs of which are cattle, sheep, and goats. Rats and mice have been implicated as reservoirs in some areas. In French Guiana the three-toed sloth is the reservoir. C. burnetti is trophic for the endometrium and mammary glands of female animals, and during pregnancy the organism reaches very high concentrations in the placenta such that at the time of parturition organisms are aerosolized and contamination of the environment occurs. Inhalation of even one microorganism can result in infection. Diagnosis is confirmed by serological testing: in acute disease antibodies to phase II antigen are higher than those to phase I, whereas the reverse is true in chronic disease.
Paracoccidioidomycosis
Authors: Shikanai-Yasuda M.A. 
Published: February 2020

Abstract
Paracoccidioidomycosis is a systemic endemic mycosis caused by dimorphic fungus found in soil and in a variety of animals, and transmitted to humans by inhalation. It is restricted geographically to Central and South America, where it is the most common endemic chronic human mycosis, acquired in rural and periurban areas. In its chronic form is is more frequqnt in men than women (10:1) and in the acute form, it is equally distributed among boys and girls (children, adolescents and young adults) areas. It involves the lung and mucous membranes, adrenal, gastrointestinal, central nervous system and other organs in thechronic form and the phagocytic mononuclear system in the acute form. Diagnosis is made by direct microscopy or culture from sputum, plus histopathology.and/or serology, which is useful for therapeutic control. Treatment is required for long courses of oral drugs (itraconazole or sulfamethoxazole– trimethoprim) for non severe cases) or intravenous amphotericin B or other amphotericin formulations in severe cases followed by oral drugs.for severe cases. Sequels are represented by microstomia, laryngeal/tracheal/bronchial stenosis, pulmonary emphysema/fibrosis, respiratory insufficiency, and cor pulmonale.
Human African trypanosomiasis
Authors: Brun Reto , Blum Johannes 
Published: February 2020

Abstract
Human African trypanosomiasis (sleeping sickness) is caused by subspecies of the protozoan parasite Trypanosoma brucei. The disease is restricted to tropical Africa where it is transmitted by the bite of infected tsetse flies (Glossina spp.). Control programmes in the 1960s were very effective, but subsequent relaxation of control measures led to recurrence of epidemic proportions in the 1980s and 1990s. Control is now being regained. Untreated human African trypanosomiasis is almost invariably fatal. Specific treatment depends on the trypanosome subspecies and the stage of the disease. Drugs used for stage 1 include pentamidine and suramin, and for stage 2 include melarsoprol, eflornithine, and nifurtimox, but regimens are not standardized, and treatment is difficult and dangerous; all of the drugs used have many side effects, some potentially lethal.
Cutaneous filariasis
Authors: Burnham Gilbert 
Published: February 2020

Abstract
The cutaneous filariae are transmitted by biting insects. Some, such as Onchocerca volvulus, are transmitted by Simulium flies and can cause debilitating conditions such as visual impairment and disfiguring skin conditions. The Mansonella infections are transmitted either by Simulium flies or biting midges (genus Culicoides), but consequences of infections are general mild. Loa loa is transmitted by the bite of the Chrysops fly. Loaisis is manifest by adult worms periodically passing beneath the sclera and by subcutaneous swellings, usually of the forearm. Onchocerciasis, or river blindness, historically occurred in 34 countries in Africa, Yemen, and Latin America. It is estimated that 18 million people are infected, and 87 million at risk of infection. Most are in Africa. Mass treatment with ivermectin has now greatly lessened the ocular burden of infection.
Strongyloidiasis, hookworm, and other gut strongyloid nematodes
Authors: Brown Michael 
Published: February 2020

Abstract
Strongyloides stercoralis and hookworms are common soil-transmitted nematodes in tropical and subtropical regions. After the organisms penetrate exposed skin, most infections are asymptomatic, but heavy infections can result in significant morbidity. The roundworm S. stercoralis infects an estimated 30 million to 100 million people. Infection is persistent and may present decades after exposure. Diagnosis is usually by microscopy or culture of stool; serology is useful as a screening test. Treatment is typically with ivermectin or albendazole. Improved sanitation and appropriate footwear can reduce the acquisition of infection. Hookworm infections, mainly caused by Ancylostoma duodenale and Necator americanus, affect more than 500 million people, predominantly in sub-Saharan Africa and Asia. Population-based control programmes, using single-dose antihelmintic therapies, aim to reduce anaemia, and improve childhood growth and cognitive development in countries with high prevalence of soil-transmitted helminths.
Cestodes (tapeworms)
Authors: Knight Richard 
Published: February 2020

Abstract
Adult tapeworms maintain anchorage to the host small-gut mucosa by means the scolex, a holdfast structure. The rest of the body forms the strobila and consists of a chain of flattened proglottids, which proliferate just behind the scolex. The life cycle then includes larval stages in one or more intermediate hosts. Many species of tapeworm, all zoonoses, infect humans as adult worms or larval stages. Serious disease can result when larval stages occur accidentally in humans, whereas infections by the adult stages often cause little harm. Two groups of cestode infect humans: the Cyclophyllidea and the Pseudophyllidea. The former have a terrestrial life cycle and cystic larvae; the latter have an aquatic cycle and worm-like larvae.
Urethritis
Authors: Horner Patrick 
Published: February 2020

Abstract
Urethritis is defined as detectable urethral inflammation in the presence of symptoms or an observable urethral discharge. It is conventionally classified into gonococcal urethritis (GU, caused by Neisseria gonorrhoeae) and non-gonococcal urethritis (NGU, caused by Chlamydia trachomatis, Mycoplasma genitalium, and other causes, but with no known pathogen detected in over 30% of cases). Diagnosis is by urethral smear and microbiological investigations. Treatment with appropriate antibiotics should be given only to those with proven urethritis, and the diagnosis and its implications should be discussed with the patient. Partner notification is essential, not only to prevent re-infection but also to prevent onward transmission from partner(s) and the development of complications if left untreated.
Genital ulceration
Authors: French Patrick , Patel Raj 
Published: February 2020

Abstract
Genital ulceration can be caused by many common and rare sexually transmitted infections (STIs), dermatological conditions, and trauma. Key to making a specific diagnosis that will direct treatment is a standard sexual and travel history followed by appropriate diagnostic tests. Genital ulcer disease is a major risk factor for the acquisition and transmission of HIV. Various classifications and algorithms are proposed to help identify pathogens and guide immediate management, but care must be taken when working through these.
Anogenital lumps and bumps
Authors: de Vries Henry J.C. , Lacey Charles J.N. 
Published: February 2020

Abstract
Anogenital lesions can be related to sexually transmitted infections, physiological variants that worry the patient, or dermatological conditions unrelated to infection. The clinical diagnostic approach is based on the colour of the lesion and the skin layer involved (epidermis, dermis, or subcutaneous fat compartment). A strong element of pattern recognition is involved in accurate diagnosis. This can only be learnt with experience, but is essential for determination of appropriate treatment. In this chapter the most common anogenital dermatological diagnoses are discussed using an approach based on the colour of the lesion and the skin layer involved. Many of these infections are asymptomatic, enabling ongoing transmission. Some sexually transmitted infections cause symptoms, especially in the anogenital region, and therefore need to be considered in the differential diagnosis of patients presenting with anogenital lesions.
Diving medicine
Authors: Denison David M. , Glover Mark A. 
Published: February 2020

Abstract
Diving remains the principal means of exploring and exploiting shallower underwater zones. Immersion and rapid change in pressure with depth cause most problems unique to diving. Gas density, partial pressures, and solubility vary proportionately with ambient pressure. At elevated partial pressure, nitrogen becomes narcotic, as can other inert gases, and contaminants barely detectable at the surface can become toxic. Hyperoxia irritates the lungs and the central nervous system, sometimes causing generalized seizures. A safe gas mixture at depth can become hypoxic as the partial pressure of oxygen decreases during the return to surface. Ventilation is compromised at depth and failure of CO2 elimination increasingly limits activity. Some divers are not distressed by elevated CO2, but this does not protect them from its toxic effects.
Air pollution and health
Authors: Kurmi Om P. , Lam Kin Bong Hubert , Ayres Jon G. 
Published: February 2020

Abstract
The term ‘occupational and environmental health’ includes any act of emission of any substance, likely to be hazardous in nature, which is either not originally present or is present in a higher concentration than normal in the natural atmosphere. Most air pollutants are generated from human activities (e.g. energy, transportation, industry, agriculture), but natural events in the living (e.g. methane emissions in wetlands) and non-living environment (e.g. volcanic eruptions) also contribute to atmospheric air pollution, although their relative importance has declined since the Industrial Revolution and the advent of modern fossil fuel-based economies. Pollutants may be classified as (1) primary (emitted directly into the atmosphere) or secondary (formed in the air through chemical reactions with other pollutants and gases); (2) indoor or outdoor; (3) gaseous or particulate.
Cold
Authors: Stroud Michael A. 
Published: February 2020

Abstract
Humans are poorly adapted to cold, which can cause hypothermia, non-freezing cold injury, and frostbite. Hypothermia occurs especially with wind and wetting, and is seen indoors in older people and those who are thin. Non-freezing cold injury occurs when skin temperatures below 12°C are maintained for prolonged periods, particularly in water. This causes paralysis of nerve and muscle, which can be permanent (e.g. trench foot). Meanwhile, with frostbite the frozen tissues initially appear hard, white, and anaesthetic, but with rewarming become swollen, painful, and blistered. There may be irreversible necrosis, but initial appearances can be misleading and hence early amputation should be avoided. Once thawed, frostbite treatment is similar to that for burns.
Drowning
Authors: Fenner Peter J. 
Published: February 2020

Abstract
Drowning is a major preventable cause of death, most frequently in children and in developing countries. Aspiration (whether of salt or fresh water) is usual in drowning and near-drowning (known as non-fatal, or submersion injury) and leads to cardiac arrest within a few minutes. Death or severe neurological impairment occurs after submersion for more than 5–10 min, but much longer durations may be tolerated in hypothermic conditions. Prognosis cannot reliably be predicted, but cardiovascular status is a better prognostic indicator than neurological presentation. Patients who are neurologically responsive at the scene of immersion, in sinus rhythm and with reactive pupils, have good outcomes. Those who are asystolic on arrival at hospital and remain comatose for more than 3 h have a poor prognosis unless they are hypothermic. Patients with a normal chest radiograph on admission usually survive.
Disasters: Earthquakes, hurricanes, floods, and volcanic eruptions
Authors: Baxter Peter J. 
Published: February 2020

Abstract
Natural disasters (including earthquakes, volcanic eruptions, hurricanes, floods) cause tens of thousands of deaths and adversely affect the lives of hundreds of millions of people every year. The trend is for the impacts to increase alongside the continuing expansion of human populations into regions at risk and with environmental degradation making human settlements more vulnerable, especially in heavily urbanized areas and megacities. This reckless development is going on in most countries of the world, even in places prone to natural disasters. Recent remarkable advances in forecasting weather-related disasters (hurricanes and floods) have to be matched with adequate disaster preparedness in those communities at high risk if they are to be translated into effective warnings, especially in low-income countries. Earthquakes remain notoriously unpredictable and have the greatest mortality toll of all natural disasters.
Poisonous plants
Authors: Eddleston Michael , Persson Hans 
Published: February 2020

Abstract
Many plants contain toxic substances—heterogeneous in chemical composition and diverse in toxic effects. When classifying plant poisonings, a pragmatic approach is to look at the main clinical effects, but it should be emphasized that few plant toxins produce just one type of symptom and that symptomatology is often multiple, with some features predominating. Ingestion of, or contact with, poisonous plants is common but serious plant poisoning is rare worldwide because most plant exposures are accidental: the majority occur in small children, the ingested dose is usually small, and no treatment is required. Treatment of severe plant poisoning includes careful decontamination and symptomatic and supportive care. Specific antidotes are only available for poisoning by plants containing belladonna alkaloids (physostigmine), cardiac glycosides (digoxin-specific Fab fragments), and cyanogenic agents (dicobalt edetate, hydroxocobalamin).
Vitamins
Authors: Hill Tom R. , Bender David A. 
Published: February 2020

Abstract
The vitamins are a disparate group of organic compounds that are required in small amounts (mg or µg per day) for the maintenance of normal health and metabolic integrity. Four vitamins (A, D, E, and K) are lipid soluble, while the others are water-soluble. Determining how much of any particular vitamin is required for health is not straightforward, a standard technique being to deprive volunteers of the vitamin in question until there is detectable metabolic change and then replete with graded doses of the vitamin until normal metabolism is restored, with the reference intake (recommended daily intake or amount or recommended dietary allowance) set at 2× standard deviation above the average requirement.
Severe malnutrition
Authors: Jackson Alan A. 
Published: February 2020

Abstract
Severe malnutrition is the consequence of systemic deficiency of energy and nutrients over a prolonged period: in children development is stunted and the individual is at risk of fatal (often clinically ‘silent’) infection and other illnesses. It is a medical and societal emergency: mortality is high, despite attempts to provide appropriate care.
When severe malnutrition affects several individuals in a society, it reflects a state in which basic needs and justice are not met. Severe malnutrition may also result from clinical disorders affecting a single person with gastrointestinal disease, poor appetite, or reduced food intake for other reasons. The World Health Organization has produced guidelines for facility-based care of patients suffering severe malnutrition, and this chapter explains the diagnosis, treatment, and management of the condition, along with its possible complications.
Disorders of galactose, pentose, and pyruvate metabolism
Authors: Cox Timothy M. 
Published: February 2020

Abstract
Inborn errors of galactose metabolism—galactose is principally found as free lactose in dairy products. Three inborn errors of galactose metabolism are recognized: (1) galactokinase deficiency (‘galactose diabetes’)—a very rare condition which impairs the assimilation of dietary galactose such that the free sugar and its metabolites appear in plasma and urine; (2) classical galactosaemia (galactose-1-phosphate uridylyltransferase deficiency)—the commonest (1/47 000 births) and most important disorder. High concentrations of galactose in the plasma and tissues lead to aberrant glycosylation of glycoproteins and other glycoconjugates, including lipids. The principal manifestations are a bactericidal defect associated with neonatal Escherichia coli sepsis; failure to thrive; and—in older patients—growth retardation, mental retardation, renal Fanconi’s syndrome, jaundice, and hepatosplenomegaly: without exclusion of lactose and galactose, death with cirrhosis is the rule. (3) Uridine diphosphate galactose-4´-epimerase deficiency—a rare but often harmless disorder which may be identified by neonatal screening. Rarely, cataract, sensorineural deafness and impaired psychomotor development with hepatorenal features of classical galactosaemia occur, with favourable responses to the galactose exclusion diet. Pentosuria—essential pentosuria is an asymptomatic, autosomal recessive trait affecting glucuronate metabolism, principally found in Ashkenazi Jews. Disorders of pyruvate metabolism—deficiency of the pyruvate dehydrogenase complex is the most common inherited disorder with lactic acidaemia, most often due to deficiency of the E1α subunit inherited as a dominant X-linked character. Presentation is with overwhelming neonatal acidosis; moderate lactic acidosis with progressive neurological features; or—in male children and young adults—an indolent neurological course without overt acidosis but with episodes of cerebellar ataxia induced by carbohydrate administration. Pyruvate carboxylase deficiency causes lactate/pyruvate acidosis with a necrotizing encephalopathy resembling Wernicke’s encephalopathy. Hypoglycaemia may complicate intercurrent infections and starvation.