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48-482: Over 20 species, see text: Digitalis ( / ˌ d ɪ dʒ ɪ ˈ t eɪ l ɪ s / or / ˌ d ɪ dʒ ɪ ˈ t æ l ɪ s / ) is a genus of about 20 species of herbaceous perennial plants, shrubs , and biennials , commonly called foxgloves . Digitalis is native to Europe, Western Asia, and northwestern Africa. The flowers are tubular in shape, produced on a tall spike, and vary in colour with species, from purple to pink, white, and yellow. The name derives from

96-466: A " stool ", removes everything but vital parts of the plant, resulting in long new stems known as "canes". Other shrubs respond better to selective pruning to dead or unhealthy, or otherwise unattractive parts to reveal their structure and character. Shrubs in common garden practice are generally considered broad-leaved plants , though some smaller conifers such as mountain pine and common juniper are also shrubby in structure. Species that grow into

144-577: A century ago) is called a shrubbery , shrub border or shrub garden. There are many garden cultivars of shrubs, bred for flowering, for example rhododendrons , and sometimes even leaf colour or shape. Compared to trees and herbaceous plants, a small number of shrubs have culinary usage. Apart from the several berry -bearing species (using the culinary rather than botanical definition), few are eaten directly, and they are generally too small for much timber use unlike trees. Those that are used include several perfumed species such as lavender and rose , and

192-466: A number of species now seen as synonyms of Digitalis purpurea , or others: D. dubia , D. leucophaea , D. micrantha and D. trojana . As of 2017, Plants of the World Online recognises the following 27 species (and a number of hybrids): The first full monograph regarding this genus was written by Lindley in 1821. He included two sections, a section Isoplexis including two species, and

240-456: A reasonable length beforehand. Many trees can grow in multiple stemmed forms also while being tall enough to be trees, such as oak or ash . An area of cultivated shrubs in a park or a garden is known as a shrubbery . When clipped as topiary , suitable species or varieties of shrubs develop dense foliage and many small leafy branches growing close together. Many shrubs respond well to renewal pruning , in which hard cutting back to

288-400: A result of increased contractility, stroke volume is increased. Ultimately, digitalis increases cardiac output (cardiac output = stroke volume x heart rate). This is the mechanism that makes this drug a popular treatment for congestive heart failure, which is characterized by low cardiac output. Digitalis also has a vagal effect on the parasympathetic nervous system , and can be used to slow

336-517: A shrubby habit may be either deciduous or evergreen . In botany and ecology , a shrub is more specifically used to describe the particular physical canopy structure or plant life-form of woody plants which are less than 8 metres (26 ft) high and usually multiple stems arising at or near the surface of the ground. For example, a descriptive system widely adopted in Australia is based on structural characteristics based on life-form, plus

384-412: A therapy to control epilepsy around this time, and there are two paintings by the artist where the plant is present. Other studies immediately questioned this: there are a large number of other possible explanations for van Gogh's choice of palette, there is no evidence that van Gogh was ever given the drug or that his physician prescribed it, he was tested and had no xanthopsia , and in his many letters of

432-595: A wide range of plants with medicinal uses. Tea and coffee are on the tree-shrub boundary; they are normally harvested from shrub-sized plants, but these would be large enough to become small trees if left to grow instead. Shrubs are perennial woody plants, and therefore have persistent woody stems above ground (compare with succulent stems of herbaceous plants ). Usually, shrubs are distinguished from trees by their height and multiple stems. Some shrubs are deciduous (e.g. hawthorn ) and others evergreen (e.g. holly ). Ancient Greek philosopher Theophrastus divided

480-520: Is about 7 days and not affected by kidney function. Both molecules include a lactone and a triple-repeating sugar called a glycoside . Digitalis works by inhibiting sodium-potassium ATPase . This results in an increased intracellular concentration of sodium ions and thus a decreased concentration gradient across the cell membrane. This increase in intracellular sodium causes the Na/Ca exchanger to reverse potential, i.e., transition from pumping sodium into

528-534: Is also used for drug preparations that contain cardiac glycosides , particularly one called digoxin , extracted from various plants of this genus. Foxglove has medicinal uses but is also very toxic to humans and other animals, and consumption can even lead to death. The generic epithet Digitalis is from the Latin digitus (finger). Leonhart Fuchs first invented the name for this plant in his 1542 book De historia stirpium commentarii insignes ( Notable comments on

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576-406: Is extracted from D. lanata . Digoxigenin can be used as a molecular probe to detect mRNA in situ and label DNA, RNA, and oligonucleotides . It can easily be attached to nucleotides such as uridine by chemical modifications. DIG molecules are often linked to nucleotides; DIG-labelled uridine can then be incorporated into RNA via in vitro transcription . Once hybridisation occurs, RNA with

624-414: Is no empirical evidence for these claims, and it is not used for these conditions in modern medicine, only for slowing excessive heart rate in certain circumstances and/or strengthening heart muscle contraction in heart failure. Digitalis is an example of a drug derived from a plant that was formerly used by herbalists ; herbalists have largely abandoned its use because of its narrow therapeutic index and

672-455: Is sometimes brewed into a tea, with fatal consequences. Other fatal accidents involve children drinking the water in a vase containing digitalis plants. Drying does not reduce the toxicity of the plant. The plant is toxic to animals, including all classes of livestock and poultry, as well as felines and canines. According to 1981 speculation, Vincent van Gogh 's "Yellow Period" may have been influenced by digitalis, because it had been proposed as

720-432: Is to increase contraction of the cells, both in force and frequency, tending to produce tachycardia (increased heart rate), depending on the dose, the condition of one's heart, and the prevailing chemistry of the blood (specifically any of: low potassium, high calcium and low magnesium). Electrical cardioversion (to "shock" the heart) is generally not indicated in ventricular fibrillation in digitalis toxicity, as it can make

768-424: Is toxic (including the roots and seeds). Mortality is rare, but case reports do exist. Most plant exposures occur in children younger than six years and are usually unintentional and without associated significant toxicity. More serious toxicity occurs with intentional ingestion by adolescents and adults. In some instances, people have confused foxglove with the relatively harmless comfrey ( Symphytum ) plant, which

816-783: The Flora of Turkey , which was finally completed in 1985. In 1963 he obtained a D.Sc. qualification from the University of Edinburgh , presenting the thesis "Contributions to the flora of Turkey" . He was invited to serve as regional adviser for Turkey on the Flora Europaea project. He was awarded the Symposium Medal during the International Symposium on the Problems of Balkan Flora and Vegetation , and

864-964: The Flora of Turkey and the East Aegean Islands . In 1952 he received his PhD on Taxonomy of Middle East flora . In the 1950s, Davis made many overseas trips, collecting plants in Kurdistan, Russia and the Middle East. In 1959 he was honoured with the Cuthbert Peek Award of the Royal Geographical Society for his expedition to Kurdistan. In 1955 he was elected a Fellow of the Royal Society of Edinburgh . His proposers were Sir William Wright Smith , Alexander Nelson, John Anthony and Brian Burtt . From 1961 he intensified his efforts to complete

912-399: The 19 species, but molecular studies into the phylogeny of the genus published in 2004 found that although four of Werner's sections were supported by the genetics, the section Tubiflorae was polyphyletic , and that the species D. lutea and D. viridiflora should be placed in the section Grandiflorae . This study, as well as a number of other studies published around that time, reunited

960-414: The 2004 study found these two species situated within the section Globiflorae . Larvae of the foxglove pug , a moth, consume the flowers of the common foxglove for food. Other species of Lepidoptera eat the leaves, including the lesser yellow underwing . The shape of the foxglove's flowers makes it especially attractive to long-tongued bees, such as the common carder bee . The bright flowers attract

1008-517: The Food and Drug Administration and the guideline recommendations, the therapeutic use of digoxin is declining in patients with heart failure—likely the result of several factors. The main factor is the more recent introduction of several drugs shown in randomised controlled studies to improve outcomes in heart failure. Safety concerns regarding a proposed link between digoxin therapy and increased mortality seen in observational studies may have contributed to

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1056-756: The Latin word for "finger". The genus was traditionally placed in the figwort family, Scrophulariaceae , but phylogenetic research led taxonomists to move it to the Veronicaceae in 2001. More recent phylogenetic work has placed it in the much enlarged family Plantaginaceae . The best-known species is the common foxglove, Digitalis purpurea . This biennial is often grown as an ornamental plant due to its vivid flowers, which range in colour from various purple tints through pink and purely white. The flowers can also possess various marks and spottings. Other garden-worthy species include D. ferruginea , D. grandiflora , D. lutea , and D. parviflora . The term digitalis

1104-458: The Middle East and Turkey, but had to break off his trip in 1939 at the beginning of World War II. He was called up into the army and served until 1945. The last two years of his time in the army he spent time in Cairo . Immediately after he was demobbed, Davis moved to Scotland to study botany and biology at the University of Edinburgh . In 1950 he began the research project that eventually became

1152-413: The Na/Ca exchanger to provide all or a majority of the cytoplasmic calcium required for cardiac contraction. For this to occur, cytoplasmic sodium must exceed its typical concentration to favour a reversal in potential, which naturally occurs in human newborns and some animals primarily through an elevated heart rate; in patients with chronic heart failure it occurs through the administration of digitalis. As

1200-424: The appearance of blurred outlines ('halos'). Other things mentioned are dilated pupils, drooling, weakness, collapse, seizures, and even death. Digitalis poisoning can cause indirect inhibition of the atrioventricular node via a direct effect on the vagal nucleus . This results in bradycardia (decreased heart rate) or if severe enough, heart block . The direct effect of cardiac glycosides on heart muscle cells

1248-572: The bee, which lands on the lower lip of the bloom before climbing up the tube. This means that the bee is likely to drop any pollen it may have collected from other foxgloves, thereby facilitating propagation. Nicholas Culpeper included Foxglove in his 1652 herbal medicine guide, The English Physician . He cited its use for healing wounds (both fresh and old), as a purgative, for "the King's Evil" ( mycobacterial cervical lymphadenitis ), for "the falling sickness" ( epilepsy ), and for "a scabby head". There

1296-577: The cell in exchange for pumping calcium out of the cell, to pumping sodium out of the cell in exchange for pumping calcium into the cell. This leads to an increase in cytoplasmic calcium concentration, which improves cardiac contractility. Under normal physiological conditions, the cytoplasmic calcium used in cardiac contractions originates from the sarcoplasmic reticulum , an intracellular organelle that stores calcium. Human newborns, some animals, and patients with chronic heart failure lack well developed and fully functioning sarcoplasmic reticula and must rely on

1344-458: The classification as proposed by Davis was largely correct: Globiflorae contained as distinct species D. cariensis , D. ferruginea , D. lamarckii , D. lanata and D. nervosa , and D. trojana was subsumed at the infraspecific rank as D. lanata subsp. trojana . This study listed 23 species: D. transiens , D. cedretorum , D. ikarica and D. fuscescens were not mentioned. D. parviflora and D. subalpina were not tested in this study, but

1392-502: The control of ventricular response rate for patients with atrial fibrillation. American College of Cardiology/American Heart Association guidelines recommend digoxin for symptomatic chronic heart failure for patients with reduced systolic function, preservation of systolic function, and/or rate control for atrial fibrillation with a rapid ventricular response. Heart Failure Society of America guidelines for heart failure provide similar recommendations. Despite its relatively recent approval by

1440-407: The decline in therapeutic use of digoxin, however a systematic review of 75 studies including four million patient years of patient follow-up showed that in properly designed randomised controlled studies, mortality was no higher in patients given digoxin than in those given placebo. Romani people use foxglove to treat eczema. A group of pharmacologically active compounds are extracted mostly from

1488-474: The difficulty of determining the amount of active drug in herbal preparations. Once the usefulness of digitalis in regulating the human pulse was understood, it was employed for a variety of purposes, including the treatment of epilepsy and other seizure disorders, which are now considered to be inappropriate treatments. A group of medicines extracted from foxglove plants are called digitalin . The use of D. purpurea extract containing cardiac glycosides for

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1536-531: The foxes made their dens were often covered with the toxic flowers. Some of the more menacing names, such as "witch's glove", reference the toxicity of the plant. Henry Fox Talbot (1847) proposed 'folks' glove', where 'folk' means fairy. Similarly, R. C. A. Prior (1863) suggested an etymology of 'foxes-glew', meaning 'fairy music'. However, neither of these suggestions account for the Old English form foxes glofa . The Flora Europaea originally recognised

1584-466: The genus Isoplexis with Digitalis , increasing the number of species to 23. Peter Hadland Davis , an expert on the flora of Turkey , had used a different circumscription than Werner in his works, and recognised eight species in the country. A 2016 molecular phylogenetic study into the relationships of the Turkish species in the section Globiflorae aimed to reconcile this discrepancy, finding that

1632-467: The height and amount of foliage cover of the tallest layer or dominant species . For shrubs that are 2–8 metres (6.6–26.2 ft) high, the following structural forms are categorized: For shrubs less than 2 metres (6.6 ft) high, the following structural forms are categorized: Those marked with * can also develop into tree form if in ideal conditions. Peter Hadland Davis Peter Hadland Davis FLS, FRSE (18 June 1918 – 5 March 1992)

1680-553: The history of plants ), based upon the German vernacular name Fingerhut , which translates literally as 'finger hat', but actually means 'thimble'. The name is recorded in Old English as 'foxes glofe/glofa' or 'fox's glove'. Over time, folk myths obscured the literal origins of the name, insinuating that foxes wore the flowers on their paws to silence their movements as they stealthily hunted their prey. The woody hillsides where

1728-529: The incorporated DIG-U can be detected with anti-DIG antibodies conjugated to alkaline phosphatase . To reveal the hybridised transcripts, a chromogen can be used which reacts with the alkaline phosphatase to produce a coloured precipitate. Depending on the species, the digitalis plant may contain several deadly physiological and chemically related cardiac and steroidal glycosides. Thus, the digitalis plants have earned several, more sinister, names: dead man's bells and witch's gloves. The toxins can be absorbed via

1776-399: The irregular (and often fast) atrial fibrillation . Digitalis is hence often prescribed for patients in atrial fibrillation, especially if they have been diagnosed with congestive heart failure . Digoxin was approved for heart failure in 1998 under current regulations by the Food and Drug Administration on the basis of prospective, randomized study and clinical trials. It was also approved for

1824-560: The leaves of the second year's growth, and in pure form are referred to by common chemical names, such as digitoxin or digoxin , or by brand names such as Crystodigin and Lanoxin, respectively. The two drugs differ in that digoxin has an additional hydroxyl group at the C-3 position on the B-ring (adjacent to the pentane). This results in digoxin having a half-life of about one day (and increasing with impaired kidney function), whereas digitoxin's

1872-438: The main section Digitalis with three subsections, including 2Y species, a number of which are now seen as synonyms or hybrids. In the last full monograph of the genus in 1965, Werner classified the 19 recognised species in five sections (four species from Macaronesia were separated in the genus Isoplexis at the time): In their 2000 book about Digitalis , Luckner and Wichtl continued to uphold Werner's classification of

1920-543: The plant world into trees, shrubs and herbs. Small, low shrubs, generally less than 2 m (6.6 ft) tall, such as lavender , periwinkle and most small garden varieties of rose , are often termed as subshrubs . Most definitions characterize shrubs as possessing multiple stems with no main trunk below. This is because the stems have branched below ground level. There are exceptions to this, with some shrubs having main trunks, but these tend to be very short and divide into multiple stems close to ground level without

1968-557: The potential to grow taller in ideal conditions. For longevity, most shrubs are classified between perennials and trees. Some only last about five years in good conditions. Others, usually larger and more woody, live beyond 70. On average, they die after eight years. Shrubland is the natural landscape dominated by various shrubs; there are many distinct types around the world, including fynbos , maquis , shrub-steppe , shrub swamp and moorland . In gardens and parks, an area largely dedicated to shrubs (now somewhat less fashionable than

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2016-446: The rhythm disturbance more complicated or sustained. Furthermore, the classic drug of choice for ventricular fibrillation in emergency setting, amiodarone , can worsen the dysrhythmia caused by digitalis, therefore, the second-choice drug lidocaine is more commonly used. Mild toxicity is treated by stopping the medication and general supportive measures; severe toxicity is treated with anti-digoxin antibody fragments . The entire plant

2064-574: The skin or ingestion. Digitalis intoxication, known as digitalism , results from an overdose of digitalis and can cause gastrointestinal, cardiac and neurological effects. The former include appetite loss, nausea, vomiting and diarrhoea; the cardiac symptoms include both tachycardia , and bradycardia (either of which, if severe enough, can result in syncope —see below); and the neurological effects include fatigue, delirium, and rarely xanthopsia (jaundiced or yellow vision). Other oculotoxic effects of digitalis include generalized blurry vision, as well as

2112-442: The time he makes it clear that he simply liked using the colour yellow, but it has remained a popular theory. Shrub Some define a shrub as less than 6 m (20 ft) and a tree as over 6 m. Others use 10 m (33 ft) as the cutoff point for classification. Many trees do not reach this mature height because of hostile, less than ideal growing conditions, and resemble shrub-sized plants. Others in such species have

2160-491: The treatment of heart conditions was first described in the English-speaking medical literature by William Withering , in 1785, which is considered the beginning of modern therapeutics. In contemporary medicine, digitalis (usually digoxin ) is obtained from D. lanata . It is used to increase cardiac contractility (it is a positive inotrope ) and as an antiarrhythmic agent to control the heart rate, particularly in

2208-436: The ventricular rate during atrial fibrillation (unless there's an accessory pathway , when it can paradoxically increase the heart rate). The dependence on the vagal effect means digitalis is not effective when a patient has a high sympathetic nervous system drive, which is the case with acutely ill persons, and also during exercise. Digoxigenin (DIG) is a steroid found in the flowers and leaves of Digitalis species, and

2256-731: Was a British botanist. Davis was born on 18 June 1918 in Weston-super-Mare . Initially he was educated at the Nash House, Burnham-on-Sea and then continued his education at Bradfield College and later in Maiden Erlegh near Reading, Berkshire . In 1937 he began training at Ingwersen 's Alpine Plant Nursery in East Grinstead and became interested in botany. In 1938 he began his first botanical expedition, albeit as an amateur on his own initiative. He visited

2304-692: Was honoured by the Turkish government for his outstanding achievements in science. He later received the Gold Medal of the Linnean Society of London for his commitment to the Royal Botanic Garden Edinburgh . In the 1980s, he was awarded the Neill Medal of the Royal Society of Edinburgh for his contributions to plant taxonomy. Peter was not only a plant collector but a collector of pottery and modern art. He had

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