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.

ascus

pl. asci; the spore case of Ascomycetes.
References in periodicals archive ?
Table 1--Demographic characteristics of die study population CYTOLOGICAL DIAGNOSIS DEMOGRAPHIC PARAMETERS NILM ASCUS Mean age 34.
They added that the absence of any high-grade lesions among 845 HPV-negative women with ASCUS cytology "strongly supports the use of HPV in triaging ASCUS when cytology is performed first, as previously reported.
This is different from reflex HPV testing, which takes effect only when a smear is interpreted as ASCUS.
En Estados Unidos existen protocolos de recoleccion, que mezclan el test de VPH con la citologia: en el momento de tomar la citologia convencional se recoge una segunda muestra cervical y se reserva para la tipificacion del VPH, en caso de que el resultado de la citologia corresponda a un ASCUS.
TABLE 4 Parity Number LSIL HSIL ASCUS AGCUS of cases 0 11 1 55 1(1.
4% of ASCUS progressed to HSIL and 7% of LSIL progressed to HSIL.
Another computer-based model evaluated different triage strategies for ASCUS Pap smears and found that reflex HPV testing provides the same or greater life expectancy benefits and is more cost-effective.
In the ongoing ASCUS/LSIL Triage Study (ALTS), a $28 million project funded by the National Cancer Institute, a panel of cytopathologists agreed with original readings of ASCUS (atypical squamous cells of undetermined significance) only 50% of the time, and the majority of reinterpretations were downgraded to normal.
According to the study, more than 75% of patients whose ASCUS smears returned to a normal level also tested negative with the manufacturer's assay.
HPV genotyping may be important to assessing the risk of developing pre-cancerous conditions or cervical cancer in women with either ASCUS (an ambiguous type of cellular abnormality formally called "atypical squamous cells of undetermined significance") or LSIL (mildly abnormal cells formally called "low-grade squamous intraepithelial lesions") results of Pap testing.