Life and health

Microsatellite analysis

Microsatellite analysis is a genotyping method that amplifies short tandem-repeat loci by PCR and sizes the fragments to assign codominant genotypes, underpinning forensics, linkage mapping, and parentage testing.

Microscale thermophoresis

Microscale thermophoresis (MST) is an optical biophysical method that measures biomolecular binding in free solution by moving fluorescently labeled molecules in a laser-induced temperature gradient, yielding affinities in about 10 minutes without surface immobilization.

Microscopic colitis

Microscopic colitis (collagenous colitis, lymphocytic colitis) is a chronic inflammatory bowel disease causing watery diarrhea with normal colonoscopy, diagnosed by biopsy histology; budesonide is first-line therapy.

Microscopic haematuria

Microscopic haematuria, or microhematuria, is 3 or more red blood cells per high-power field on urine microscopy with normal-appearing urine. Guided by AUA/SUFU risk stratification (low, intermediate, high) for cystoscopy and imaging.

Microscopic polyangiitis

Microscopic polyangiitis (MPA), also called micropolyangiitis, is a rare pauci-immune ANCA-associated small-vessel vasculitis, usually MPO-ANCA positive, causing crescentic glomerulonephritis and alveolar hemorrhage, distinct from GPA, EGPA, and polyarteritis nodosa.

Microsleep

Microsleep: brief involuntary sleep episode (a few seconds to about 30 s) during wakefulness, caused by sleep deprivation, undetectable to the sufferer, EEG-detectable, and a major factor in drowsy-driving crashes.

Microsomal triglyceride transfer protein

Microsomal triglyceride transfer protein (MTP, MTTP gene) is an ER heterodimer of a 97-kDa subunit and PDI that assembles apoB lipoproteins in liver and intestine; its loss causes abetalipoproteinemia and its inhibitor lomitapide treats HoFH.

Microsomal triglyceride transfer protein large subunit

The microsomal triglyceride transfer protein large subunit (MTTP large subunit, M subunit, or MTPα) is the 97-kDa catalytic subunit of microsomal triglyceride transfer protein, needed to assemble VLDL and chylomicrons.

Oct 20, 2026

Microspheres

Microspheres: spherical particles from ~20 nm to 1000 μm made of polymers, glass, ceramics, or hydrogels; fabricated by emulsion, spray drying, electrospraying, or microfluidics; used for drug delivery, embolization, diagnostics, and tissue engineering.

Microspore culture

Microspore culture is a plant breeding technique in which immature pollen grains are grown in vitro, diverting them to embryogenesis to produce doubled haploid plants homozygous in a single generation.

Microsporidia

Microsporidia: a phylum of unicellular obligate intracellular fungal-related parasites with resistant 1–4 µm spores and a unique ejectable polar tube; over 1,400 species, at least 15 infect humans, most commonly Enterocytozoon bieneusi.

Microsporidian spore structure and invasion mechanism

Microsporidian spores, the resistant infectious stage of microsporidia, are 1 to 12 µm fungal parasite spores that invade host cells by firing a harpoon-like polar tube.

Oct 20, 2026

Microsporidiosis

Microsporidiosis is a rare parasitic disease caused by microsporidia, spore-forming parasites related to fungi, causing chronic diarrhea and weight loss that can be severe in immunodeficient people.

Microsporidiosis in animals

Microsporidiosis in animals is the disease caused by spore-forming microsporidia parasites in mammals and birds, usually chronic, notably E. cuniculi in rabbits and E. bieneusi in livestock.

Oct 20, 2026

Microsporum

Microsporum is a dermatophyte fungus genus in Arthrodermataceae causing skin and hair ringworm; since 2017 restricted to about three species around M. canis, the cat- and dog-associated agent of tinea capitis.

Microstimulation

Microstimulation is an electrophysiological technique delivering weak currents through small electrodes to evoke neural activity, the only clinically viable way to activate neurons on fast time scales.

Microstomia

Microstomia: congenital or acquired abnormal reduction of the oral aperture (narrow mouth), coded ICD-10 Q18.5 and ICD-11 LA31.4. Main causes are burns, caustic ingestion, scleroderma, and lip cancer surgery; treated with splints or commissuroplasty.

Microsurgery

Microsurgery is a surgical technique that uses an operating microscope and fine instruments to join blood vessels, nerves, and lymphatic vessels below about 3 mm in diameter.

Microsurgical reconstruction

Microsurgical reconstruction uses an operating microscope to reattach or transplant blood vessels with lumens under 3 mm, so a transferred flap or amputated part regains a blood supply; it underpins microsurgical breast reconstruction.

Microtia

Microtia is a congenital underdevelopment of the external ear, ranging from a small malformed auricle to anotia; about 1 in 3,800 US births, usually unilateral, treated by rib cartilage or porous polyethylene reconstruction and bone conduction hearing devices.

Microtia reconstruction

Microtia reconstruction is a surgical procedure that builds an external ear for patients with microtia, using rib cartilage or a porous polyethylene implant, typically around age 8.

Microtomy

Microtomy is the laboratory technique of cutting tissue, usually embedded in paraffin wax, into thin slices with a microtome for examination under a light or electron microscope.

Microtransplantation

Microtransplantation (MST) is a transplantation technique, born in China, that infuses small amounts of HLA-mismatched donor stem cells after chemotherapy to fight acute myeloid leukemia with low graft-versus-host disease.

Microtubule

Microtubule: hollow cytoskeletal filament of α/β-tubulin dimers, 13 protofilaments, showing dynamic instability (catastrophe/rescue) driven by GTP hydrolysis; nucleated at centrosomes and other MTOCs; forms mitotic spindle and transport tracks.

Microtubule associated protein 1

Microtubule associated protein 1 (MAP1) is a family of microtubule-stabilizing proteins comprising MAP1A, MAP1B, and MAP1S, expressed mainly in neurons, where MAP1A and MAP1B support axon and dendrite development.

Microtus

Microtus (Schrank, 1798) is the genus of Holarctic voles, Arvicolinae, with about 60 species in six subgenera, ever-growing molars, rapid 1.3-million-year radiation, 2-5 year population cycles, and major crop-pest species like the common and meadow voles.

Microvascular anastomosis

Microvascular anastomosis is the surgical connection of blood vessels under 3 mm wide, done under magnification to restore blood flow in free flap and replantation surgery.

Microvascular decompression

Microvascular decompression is a neurosurgical operation that moves an offending blood vessel away from a compressed cranial nerve, most often to relieve trigeminal neuralgia, hemifacial spasm, or glossopharyngeal neuralgia.

Microvascular Density

Microvascular density (MVD, microvessel density) is the measured density of microvessels in a tissue field, a surrogate biomarker of angiogenesis. Developed by Weidner et al. in 1991, it is assessed by endothelial immunohistochemistry (factor VIII, CD31, CD34, CD105) and studied as a prognostic marker in solid tumors.