ascus


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ascus

 [as´kus]
the spore case of certain fungi.

ASCUS

In the Bethesda system, acronym for atypical squamous cells of undetermined significance , under cell.
See also: Bethesda system.

as·cus

, pl.

as·ci

(as'kŭs, as'ī),
The saclike cell of Ascomycetes in which ascospores develop following nuclear fusion and meiosis.
[G. askos, bag]

ASCUS

Atypical squamous cell of undetermined significance Cytology A cell seen in a pap smear of the cervix that fulfills some of the criteria–eg nuclear enlargement and irregularity, cytoplasmic clearing, and thickened cell membranes, that define cells typical of either a condyloma or a neoplasm. See CIN, HSIL, LSIL. Cf AGUS, SIL.

ASCUS

Abbreviation for atypical squamous cells of undetermined significance.
Ascusclick for a larger image
Fig. 50 Ascus . An ascus containing ascospores of Neurospora crassa.

ascus or (formerly) theca

(pl. asci) a cell present in the fruiting body of ASCOMYCETE fungi in which the fusion of HAPLOID nuclei occurs during sexual reproduction. This is normally followed by MEIOSIS, giving rise to four haploid cells, after which MITOSIS produces eight ASCOSPORES. The precise arrangement of ascospores within the ascus enables the events at meiosis to be fully analysed (see TETRAD ANALYSIS). The asci are usually enclosed within an aggregation of hyphae termed an ASCOCARP, a number of different types being recognized, e.g. perithecium, cleistothecium, apothecium.
References in periodicals archive ?
Among the women with serial Pap smear screening (3 or more) the majority did not progress beyond ASCUS. No one in this study progressed to HSIL.
studied two approaches to triage women with ASCUS or LSIL: 1) repeating the cytological test, and 2) DNA testing for high-risk types of the human papillomavirus (hrHPV) - the main causal factor of cervical cancer.
Total cervical smears done in 2007 and 2009, with a breakdown of results Cervical 2007 2009 cytology n (%) n (%) results Unsuitable 10 (1.1) 29 (1.8) Normal 654 (73.8) 1 096 (67.3) Benign changes 48 (5.4) 85 (5.2) Atypia 7 (0.8) 32 (2.0) ASCUS 30 (3.4) 30 (1.8) ASC-H 1 (0.1) 5 (0.3) AGUS 1 (0.1) 3 (0.2) LSILs 93 (10.5) 221 (13.6) HSILs 36 (4.1) 125 (7.7) Malignant 6 (0.7) 2 (0.1) Total 886 (100.0) 1 628 (100.0) ASCUS = atypical squamous cells of undetermined significance; ASC-H = atypical squamous cells --cannot exclude HSIL; AGUS = atypical glandular cells of undetermined significance; LSILs = low-grade squamous intraepithelial lesions; HSILs = high-grade squamous intraepithelial lesions.
There are two categories of ambiguous pathological lesions, namely ASCUS (atypical squamous cells of undetermined significance) and AGUS (atypical glandular cells of undetermined significance).
Any Pap report of low-grade squamous intra-epithelial lesions or atypical squamous cells of undetermined significance (ASCUS) was repeated in 6 months.
The abnormalities detected were ASCUS (0.48%), ACS-H (0.06%), LSIL (0.19%), HSIL (0.37%), SCC (0.10%), AGUS (0.25%), and adenocarcinoma (0.05%).
Cannonia differs from other Xylariaceae genera by its ascus features: broad cylindrical to clavate, 8spored, with very short pedicel, inamyloid, lacking apical apparatus, and the ascus can be evanescent.
These tests have high clinical specificity for detecting disease and may also predict which women with LSIL or atypical squamous cells of unknown significance (ASCUS) have the potential to progress to cervical cancer (Fig.
Prevalence and typing of HPV DNA by hybrid capture II in women with ASCUS, ASC-H, LSIL, and AGC on ThinPrep Pap tests.