All articles starting with H
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Hispano-Moroccan War (1859–1860)
The Hispano-Moroccan War (1859–1860), called the War of Africa in Spain, saw Spain defeat Morocco, capture Tetouan, and impose the Treaty of Wad-Ras in 1860.
Hispano-Suiza
Hispano-Suiza is a Spanish luxury automobile brand founded in Barcelona in 1904 by Damià Mateu, Francisco Seix, and engineer Marc Birkigt, known for the H6.
Hispano-Suiza H6B Dubonnet Xenia
The Hispano-Suiza H6B Dubonnet Xenia is a one-off streamlined 1938 coupé built for French racing driver André Dubonnet and named for his late wife, Xenia.
Hispano-Suiza HS.404
The Hispano-Suiza HS.404 was a 20 mm aircraft cannon designed by Marc Birkigt in France in the mid-1930s and widely used in World War II.
Hispanophone
Hispanophone (Spanish: hispanófono or hispanohablante) describes a person, community, or country whose mother tongue is Spanish, and by extension the Spanish-speaking world, with over 635 million potential speakers in 2025.
Hispasat (satellite operator)
Hispasat is a Spanish satellite communications operator constituted in 1989 and based in Madrid, operating a geostationary fleet from 30° West and 61° West, controlled since 2025 by Indra.
Hispavox
Hispavox was a Spanish record label founded in Madrid in 1953 by the Vidal Zapater brothers, one of Spain's most important labels until its 1985 merger with EMI.
Hiss (song)
Hiss (song): Megan Thee Stallion single released January 26, 2024 on Hot Girl Productions; its Megan's Law line sparked a feud with Nicki Minaj, whose response "Big Foot" followed, and the track debuted at No. 1 on the Billboard Hot 100.
Hissalel (king of Ammon)
Hissalel, also written Hissal'el or Hissa'il, was a king of the Ammonites in the 7th century BC, known from an inscribed bronze bottle found at Tell Siran, Jordan, in 1972.
Hissène Habré
Hissène Habré, Chadian dictator 1982–1990, exiled in Senegal, first former head of state convicted by another country's courts; Extraordinary African Chambers life sentence 2016, €123 million reparations, died 2021.
Hisss
Hisss (Nagin: The Snake Woman) is a 2010 fantasy-horror film directed by Jennifer Lynch, starring Mallika Sherawat as a shape-shifting naagin seeking revenge when an American captures her mate; Lynch disowned the edited release, which flopped.
HIST (tokamak)
HIST (Helicity Injected Spherical Torus) is a small spherical tokamak operated by the University of Hyogo in Japan, built to test helicity injection as a non-inductive plasma current-drive method.
Histadrut (ההסתדרות)
The Histadrut, also known as the General Federation of Labour in Israel, is Israel's trade union federation, founded in 1920 and representing about 800,000 workers under Arnon Bar-David.
Histamine
Histamine is a biogenic amine synthesized from L-histidine and stored mainly in mast cells, acting through four receptors in allergic reactions, gastric acid secretion, and brain arousal.
Histamine H1 receptor
Histamine H1 receptor (HRH1), a Gq-coupled GPCR on chromosome 3p14-p21 mediating allergy symptoms; target of first- and second-generation H1 antihistamines, which act as inverse agonists.
Histamine H2 receptor
Histamine H2 receptor (HRH2, P25021), a Gs-coupled GPCR mediating gastric acid secretion; defined by burimamide in 1972, cloned 1991, target of cimetidine (Tagamet) and other H2 blockers; cryo-EM structures solved 2024.
Histamine H3 receptor
Histamine H3 receptor (H3R): a Gi/o-coupled GPCR, discovered in 1983 and cloned in 1999, acting mainly as a presynaptic autoreceptor inhibiting histamine release; pitolisant (Wakix) is its approved antagonist/inverse agonist drug for narcolepsy.
Histamine H4 receptor
Histamine H4 receptor (H4R, HRH4): fourth histamine GPCR, discovered circa 2000 via H3 homology, expressed mainly on immune cells, mediates chemotaxis; antagonists JNJ 7777120, JNJ 39758979, and toreforant reached clinical testing but none is approved.
Histamine intolerance
Histamine intolerance (HIT), or sensitivity to dietary histamine, is a proposed nonallergic food hypersensitivity attributed to impaired diamine oxidase (DAO) degradation of ingested histamine; diagnosis is unvalidated, serum DAO is contested, and a low-histamine diet is the mainstay treatment.
Histamine N-methyltransferase
Histamine N-methyltransferase (HNMT; EC 2.1.1.8) is a cytosolic enzyme that inactivates histamine by transferring a methyl group to it, one of the body's two histamine-clearing pathways.
Histamine receptors
Histamine receptors: four human G protein-coupled receptors, H1-H4, mediating histamine's effects in allergy, gastric acid secretion, and neurotransmission; H1 and H2 are established drug targets, pitolisant targets H3.
Histamine Release
Histamine release: rapid discharge of histamine from mast cell and basophil granules, typically triggered by antigen cross-linking surface IgE on FcεRI; measured historically by the histamine release test, now largely supplanted by the basophil activation test.
Histaminergic neuron
Histaminergic neurons, the brain's only histamine-releasing neurons, sit in the tuberomammillary nucleus of the posterior hypothalamus, fire as wake-promoting pacemakers, project throughout the CNS, and signal via H1–H4 receptors.
HiStarlink (氦星光联)
HiStarlink (氦星光联) is a Chinese manufacturer of space laser communication terminals, founded in Shenzhen in 2021 by Tan Jun, and supplied the Three-Body Computing Constellation's laser payloads.
Histatin/statherin family
The histatin/statherin family is a group of small human salivary peptides, including the histatins and statherin, whose genes arose by duplication and which remineralize tooth enamel and defend against Candida albicans.
Histeridae
Histeridae, clown beetles or hister beetles, is a family of over 4800 predatory beetle species under 10 mm long, living in dung, carrion, and wood-boring galleries, with retractable antennae and uses in biological control and forensics.
Histidine
Histidine (His, H) is one of the nine essential amino acids, obtained from meat, fish, eggs, and soy, whose imidazole side chain makes it a versatile catalytic residue, metal ligand, and precursor of histamine.
Histidine ammonia-lyase
Histidine ammonia-lyase (HAL, histidase, EC 4.3.1.3) catalyzes the first step of histidine catabolism, deaminating L-histidine to trans-urocanic acid using an autocatalytic MIO prosthetic group; deficiency causes histidinemia.
Histidine catabolism
Histidine catabolism is the biochemical breakdown of the essential amino acid L-histidine to glutamate via a four-step cytosolic pathway that donates a one-carbon unit to tetrahydrofolate.
Histidine kinase
Histidine kinase (HK, histidine protein kinase): enzyme that autophosphorylates on a conserved histidine and transfers phosphate to a response regulator aspartate in two-component signaling; absent from animals, dominant in bacteria, phosphorelay-based in eukaryotes.