darkfield microscopy

darkfield microscopy

Etymology: AS, deorc, hidden, feld, field; Gk, mikros, small, skopein, to look
examination of a microscopic specimen illuminated by a peripheral light source. The illumination causes the specimen to appear to glow against a dark background. In laboratory diagnosis, the technique is used primarily to identify the syphilis spirochete. Also called darkfield illumination, ultramicroscopy.
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Darkfield microscopy: positive examination
References in periodicals archive ?
The researchers used several methods for examining the cultures for spirochetes including light and darkfield microscopy, silver staining, immunohistochemical staining, molecular hybridization, and PCR analysis.
The US Centers for Disease Control and Prevention (CDC) recently updated the definitions for confirmed cases of primary and secondary syphilis and now considers Treponema pallidum PCR (Tp-PCR) to be a valid diagnostic method along with darkfield microscopy (DFM) (2), which is still considered the reference test (although it remains imperfect) (3).
Darkfield microscopy is not utilized to a great extent today in hospital microbiology laboratories.
Among the topics are light and color, diffraction and spatial resolution, phase contrast microscopy and darkfield microscopy, the fluorescence imaging of dynamic molecular processes, super-resolution imaging, and digital image processing.
3 megapixel image sensor results in crisp color quality for the most demanding brightfield and darkfield microscopy applications including clinical pathology and cytology, life science and geology.
By 1950 Germans identified Borrelia in blood form by darkfield microscopy and gave Penicillium to the sick and they recovered, if not always forever.
Direct methods include darkfield microscopy, molecular assays to detect T pallidum DNA, and histopathologic examination of biopsies of skin or mucous membranes (which can also provide indirect evidence of infection, on the basis of patterns of inflammation in the tissue).
Results of darkfield microscopy were positive for 17 (74%) of 23 patient specimens, 5 from genital mucosa and 12 from skin lesions.
Although this may seem obtuse at first consideration, Enderlein observed through darkfield microscopy from 1900 through the 1950s that we have symbionts or endobionts in our blood and tissues which are pleomorphic.
minus has not been recovered on artificial media but can be seen by using darkfield microscopy with Giemsa or Wright stains.
DECEMBER 1-4: DARKFIELD MICROSCOPY COURSE@Hilton Garden Inn Austin in Austin, Texas.
Cultures were incubated for 6 weeks at 35[degrees]C and examined weekly for spirochetes by darkfield microscopy.