72,234 articles
Host (biology)
Host (biology): the organism a parasite lives on or in, nourishing it without benefit to itself. Key types are definitive, intermediate, paratenic, reservoir, and accidental hosts, plus vectors; humans host nearly 300 parasitic worm species.
Host cell factor
Host cell factor (HCF-1, HCFC1; related HCF-2) is a family of nuclear transcriptional coactivators. HCF-1 binds VP16 and Oct-1 to activate herpesvirus immediate-early genes, is proteolytically processed into N and C subunits, and regulates cell cycle and chromatin.
Host cell factor C1 regulator 1
HCFC1R1 (HPIP, HCF-1 beta-propeller-interacting protein), gene at 16p13.3 encoding a 138-aa nuclear/cytoplasmic protein that regulates HCF-1 localization via CRM1-dependent export; studied in breast cancer metabolism.
Host disease index conventions
Host disease index conventions are the editorial rules behind lists that organize plant diseases by host plant, pairing approved common names with pathogens, guided by APS standards and ISPP naming principles.
Host Specificity
Host specificity: the degree to which a parasite or pathogen (also called host range or tropism) is restricted to particular host species. Most pathogens are specialists; specificity reflects ecological encounter filters, physiological compatibility, and coevolutionary history.
Host-Directed Therapy
Host-directed therapy (HDT) treats infections by targeting host cell factors and immune pathways instead of the pathogen, as an adjunct against antimicrobial resistance in tuberculosis, viral hepatitis, COVID-19, and sepsis.
Host-Parasite Interactions
Host-parasite interactions are the relationships in which a parasite draws resources from its host for survival and reproduction while the host mounts defenses against infection.
Host-Pathogen Interactions
Host-pathogen interactions: the dynamic interplay between hosts and infective agents (bacteria, viruses, fungi, parasites), covering damage-response frameworks, immune evasion, host genetics, systems modeling, and host-directed therapies.
Host-seeking and prey biology of scolioid wasps
Scolioid wasps are parasitoid hunting wasps whose females locate buried scarab beetle grubs by chemical cues, paralyze them with a sting, and lay one egg on each host.
Hosta
Hosta, or plantain lily, is a genus of shade-loving foliage perennials in Asparagaceae native to East Asia, introduced to the West by von Siebold in 1829-1830, with thousands of registered cultivars and slugs and Hosta Virus X as chief problems.
Hot flash
Hot flash (hot flush): sudden feeling of heat in the upper body and face, the main vasomotor symptom of menopause, lasting 30 seconds to 10 minutes; affects up to 80% of midlife women, also men on androgen deprivation therapy; treated with hormone therapy, hypnosis, CBT, SSRIs/SNRIs, gabapentin, fezolinetant, elinzanetant.
Hot plate test
The hot plate test is a behavioral pharmacology assay measuring how quickly a mouse or rat responds to a heated surface, used mainly to screen analgesic drugs.
Hot springs as microbial habitats
Hot springs are geothermal features, including geysers and mud pots, that sustain thermophilic archaea and bacteria; no known bacteria grow above 95 °C and no eukaryotes above about 65 °C.
Hot yoga
Hot yoga: yoga practiced in rooms of 95–104°F (35–40°C), including Bikram's 26-posture, 90-minute sequence created by Bikram Choudhury; covers physiology, calorie burn, safety, and pregnancy guidance.
HOTAIR
HOTAIR (HOX transcript antisense intergenic RNA) is a long non-coding RNA from the HOXC cluster that recruits PRC2 and LSD1 to repress HOXD genes in trans; its mouse knockout phenotype and PRC2 role are contested.
Hôtel-Dieu de Montréal
Hôtel-Dieu de Montréal, Montreal's first hospital, founded by Jeanne Mance in 1642 and run by the Religious Hospitallers of Saint Joseph; moved to Mount Royal in 1861, merged into the CHUM in 1996, patients transferred 2017.
Hôtel-Dieu de Paris
Hôtel-Dieu de Paris, traditionally founded by Saint Landry around 651/660, is the oldest hospital site in Paris, on the Île de la Cité beside Notre-Dame; now an AP-HP university hospital being transformed into the Nouvel Hôtel-Dieu.
Hotlines
A hotline is a direct communication channel, usually telephone, kept in readiness to provide immediate crisis assistance, counseling, referrals, and information, from suicide prevention to poison control and diplomatic use.
Hottest chili pepper
Hottest chili pepper: Pepper X, bred by Ed Currie of PuckerButt Pepper Company, holds the Guinness record since October 2023 at 2,693,000 SHU average, dethroning the Carolina Reaper (1.64 million SHU).
Hotwheels sisyphus
Hotwheels sisyphus is a ground spider (Gnaphosidae) described in 2024 from southwest China, the only species of the genus Hotwheels, named for the Hot Wheels toy brand and Sisyphus because of its coiled genitalia.
Houge-Janssens syndrome
Houge-Janssens syndrome (HJS, Jordan's syndrome for type 1) is a spectrum of rare autosomal dominant PP2A-related neurodevelopmental disorders (types 1-4, genes PPP2R5D, PPP2R1A, PPP2CA, PPP2R5C) marked by developmental delay, hypotonia, seizures, and macrocephaly or microcephaly.
Hound
Hound: a type of domestic dog bred to hunt by scent (scent hounds like the Bloodhound and Beagle) or by sight (sighthounds like the Greyhound, up to 40 mph). AKC Hound Group has 33 breeds; FCI Group 6 covers scent hounds.
Houpo Mahuang Decoction
厚朴麻黄汤 (Houpo Mahuang Decoction), a nine-herb classical formula from Zhang Zhongjing's Jingui Yaolüe for cough with floating pulse from cold fluid retention with heat; first-batch ancient classical formula, used mainly for COPD and chronic bronchitis.
Houpo Qiwu Tang
厚朴七物汤 (Houpo Qiwu Tang), Magnolia Bark Seven-Ingredient Decoction, a Zhang Zhongjing formula from the Jin Gui Yao Lue combining Houpo Sanwu Tang with Guizhi Tang minus peony for abdominal fullness with fever.
Houpo Sanwu Tang
厚朴三物汤 (Houpo Sanwu Tang), a classic formula from the Jingui Yaolüe of magnolia bark, rhubarb, and bitter orange, heavy on magnolia bark, for abdominal fullness from qi stagnation; distinguished from Xiao Chengqi Tang and Houpo Dahuang Tang only by proportions.
House burping
House burping is the American TikTok name for German Lüften, briefly opening windows even in winter to swap stale indoor air for fresh, reducing mold, humidity, and pollutants.
House Calls
House calls (home visits) are physician or clinician visits to a patient's home for diagnosis or treatment. Once 40% of US doctor visits in 1930, they fell below 1% by 1980 and revived as home-based primary care and virtual house calls.
House dust mite
House dust mite (Dermatophagoides pteronyssinus, D. farinae) is a humidity-dependent domestic arachnid whose fecal allergens Der p 1 and Der p 2 drive asthma and rhinitis; controlled trials show avoidance measures give little clinical benefit, while immunotherapy is disease-modifying.
House finch
House finch (Haemorhous mexicanus), a small red-headed North American finch, native to the West and Mexico, established in the East by a 1940 Long Island release of "Hollywood finches"; host of Mycoplasma gallisepticum conjunctivitis.
House mouse
The house mouse (Mus musculus) is a small rodent living in close association with humans, feeding on stored food, nesting in buildings, and found on every continent except Antarctica.