Life and health

Dioon

Dioon is a genus of 18 accepted cycad species in Zamiaceae, native from Mexico to Honduras. Originating about 56 Ma in eastern Mexico, it includes the slow-growing, ethnobotanically important chamal (Dioon edule).

Dioon edule

Dioon edule, chestnut dioon or chamal, a slow-growing Mexican cycad (Zamiaceae) from the Sierra Madre Oriental; dioecious, beetle-pollinated, over 2500 years lifespan, IUCN Near Threatened, CITES Appendix II, cold-hardy to about -12 °C.

Dioon holmgrenii

Dioon holmgrenii, Palmera de Sol, an endangered Mexican cycad (Zamiaceae) described in 1981, endemic to Pacific-slope pine-oak forest of Oaxaca at 580–850 m, with six genetically isolated populations.

DIOPSYS trial

DIOPSYS trial (NCT03642782): a single-arm diagnostic study at Groupe Hospitalier Paris Saint-Joseph, Paris, sponsored by Fondation Hôpital Saint-Joseph, testing the Diopsys NOVA pattern electroretinogram for early glaucoma diagnosis; 12 patients planned, started July 2018, now suspended.

Dioscorea

Dioscorea (yams), genus of c. 630 species of twining climbers in Dioscoreaceae; source of staple tuber crops (D. rotundata, D. alata, D. polystachya) and diosgenin; cosmopolitan, dioecious, x=10 Old World, x=9 New World.

Dioscorea alata

Dioscorea alata, greater yam, water yam, purple yam, or ube, is a wing-stemmed climbing yam from tropical Asia and Melanesia, cultivated for starchy tubers and domesticated independently in Asia and the Pacific.

Dioscorea rotundata

Dioscorea rotundata, white Guinea yam or white yam, is a West African domesticated yam of hybrid origin (D. praehensilis x D. abyssinica) from the Niger River basin, the main yam of the yam belt, grown for starchy tubers used in pounded yam.

Dioscoreaceae

Dioscoreaceae, the yam family (R.Br., 1810), is a pantropical monocot family in Dioscoreales with about 650 species in four genera, dominated by Dioscorea (over 600 species), the source of edible yams and steroidal saponins.

Dioscoreales

Dioscoreales, an order of monocot flowering plants with the families Dioscoreaceae, Nartheciaceae, and Burmanniaceae; its genus Dioscorea (634 species) contains the yams, a tropical staple crop grown mainly in West Africa.

Diospyros

Diospyros (persimmon, ebony) is a genus of about 700-800 Ebenaceae trees and shrubs, pantropical in range, known for D. kaki fruit, ebony timber, and naphthoquinone chemistry.

Diospyros kaki

Diospyros kaki (Oriental, Japanese, or Chinese persimmon; kaki; Sharon fruit) is a hexaploid Ebenaceae tree native to China, cultivated over 2,000 years, with PCNA non-astringent cultivars like Fuyu and astringent ones like Hachiya.

Diospyros melanoxylon

Diospyros melanoxylon (tendu, kendu, Coromandel ebony), an Ebenaceae tree native to India and Sri Lanka, whose leaves wrap bidis, supporting over 12 million livelihoods, and which yields triterpenes with reported antidiabetic activity.

Diospyros virginiana

Diospyros virginiana, American or common persimmon (possumwood, simmon), a slow-growing dioecious Ebenaceae tree of the eastern and central United States with frost-sweetened orange fruit, hard ebony-like wood, and use as rootstock for Diospyros kaki.

Dioxacarb

Dioxacarb (Elocron, Famid, Rovlinka), CAS 6988-21-2, is a phenyl methylcarbamate insecticide and reversible acetylcholinesterase inhibitor with high acute toxicity (LD50 <50 mg/kg); not approved as a plant protection active substance in the EU.

Dioxathion

Dioxathion (Delnav), CAS 78-34-2, an organophosphate cholinesterase-inhibiting insecticide and acaricide for ticks and mites on livestock and crops; cis/trans isomer mixture, now cancelled in the US and not EU-approved.

Dioxins and dioxin-like compounds

Dioxins and dioxin-like compounds (PCDDs, PCDFs, dioxin-like PCBs) are persistent organic pollutants formed as combustion and industrial by-products; TCDD is the most toxic congener, over 90% of human exposure is dietary, and toxicity is scaled with WHO TEFs.

Dip2-like domain

Dip2-like domain (InterPro IPR037337), a conserved domain of disco-interacting protein 2 (DIP2) homologs, related to adenylate-forming enzymes; DIP2 proteins carry two such AFD domains plus a DMAP1-binding domain and act in lipid and neuronal maintenance.

Dipak Kotecha

Dipak Kotecha is a British cardiologist, Professor of Cardiology and Cardiac Imaging at the University of Birmingham, known for research on heart failure and atrial fibrillation and for chairing the 2024 ESC atrial fibrillation guidelines.

Dipali Sashital

Dipali Sashital is an American biochemist and professor at Iowa State University who studies CRISPR-Cas bacterial immune systems and received a 2025 Presidential Early Career Award for Scientists and Engineers.

Dipanjan Chowdhury

Dipanjan Chowdhury is a molecular biologist who studies DNA repair and genome stability, and is Svanberg Family Professor at Harvard Medical School and Chief of Radiation and Genomic Stability at Dana-Farber.

Dipanjan Pan

Dipanjan Pan is a nanomedicine researcher who holds the Huck Chair Professorship at Pennsylvania State University, known for 2020 nanoparticle tests diagnosing COVID-19 in 10 minutes.

Dipankar Sen

Dipankar Sen is an Indian-born biochemist at Simon Fraser University since 1991, known for early Nature papers on four-stranded G4-DNA and for showing that DNA can act as a catalyst.

Dipeptidyl peptidase-4

Dipeptidyl peptidase-4 (DPP-4, DPP-IV, CD26, EC 3.4.14.5) is a serine protease discovered in 1966 that inactivates incretin hormones GLP-1 and GIP; its inhibitors (sitagliptin, vildagliptin) treat type 2 diabetes with low hypoglycemia risk and neutral cardiovascular outcomes.

Dipeptidyl peptidase-4 inhibitor

Dipeptidyl peptidase-4 (DPP-4) inhibitors, or gliptins, are oral type 2 diabetes drugs that prolong incretin action; sitagliptin was first approved in 2006, with neutral cardiovascular outcomes but a saxagliptin heart failure signal.

DIPG trial

DIPG trial: clinical studies for diffuse intrinsic pontine glioma (DIPG), a fatal pediatric brainstem tumor. Key trials include hypofractionated radiotherapy comparisons, BIOMEDE targeted therapy, NCT03620032 re-irradiation, and CAR T studies.

Diphacinone

Diphacinone (diphenadione, CAS 82-66-6) is a first-generation indandione anticoagulant rodenticide inhibiting vitamin K epoxide reductase; multi-dose rat, mouse, vole, and island rodent control poison, WHO Class IA, vitamin K1 antidote.

Diphallia

Diphallia (duplicate penis) is an extremely rare congenital anomaly, about 1 in 5–6 million births, with roughly 100 reported cases since Wecker's 1609 report; it ranges from accessory tissue to complete penile duplication with associated anomalies.

Diphasiastrum

Diphasiastrum, ground cedars, is a genus of clubmosses (Lycopodiaceae) published by Holub in 1975, with flattened fan-like branches, underground mycorrhizal gametophytes, x=23, and extensive hybridization in Central Europe; sometimes synonymized with Lycopodium.

Diphasiastrum digitatum

Diphasiastrum digitatum (Dill. ex A. Braun) Holub, southern ground-cedar or fan clubmoss, is a North American clubmoss (Lycopodiaceae) with flat fan-shaped branches, 15–50 cm erect shoots, and 2–5 strobili, native from eastern Canada to the eastern and north-central USA, globally secure (G5).