Biomedical subjects

D C Abrams

Publications and source records attributed to D C Abrams.

4 recordsLinked to original sources

PubMed1997

Follicular density in ovarian biopsy of infertile women: a novel method to assess ovarian reserve.

The ageing ovary appears to be characterized by depletion of primordial follicles. The relationship between infertility and the number of follicles in the ovarian cortex is not known. Moreover, there are no accurate markers or clinical methods to predict the decline in ovarian reserve. This study investigates the correlation between early follicular follicle stimulating hormone, ovarian size and follicular density in 60 infertile women aged 19-45 years (mean = 34.4 +/- 5.5). An ovarian biopsy was taken from each patient while performing diagnostic laparoscopy (n = 28) or laparotomy for tubal surgery or myomectomy (n = 32). The median number of follicles was similar in tubal and unexplained infertility patients (9.5 versus 5.5). Increasing age showed a significant negative correlation with follicular density and ovarian volume (r = -0.46, P = 0.0003;. r = -0.43, P = 0.0016, respectively). In women > or = 35 years of age the ovarian volume showed a strong correlation with follicular density (r = 0.71, P < 0.0001). Our results indicate that infertile women in their late thirties and over have a decreased ovarian reserve which could possibly be predicted by ovarian volume measurement. Ovarian biopsy may have a place as part of infertility evaluation in older women.

Adult↗

PubMed1997

Stereological estimation of blood vessel surface and volume densities in human normal and rhinitic nasal mucosa.

A technique is proposed for applying well-established stereological methods to study fixed nasal biopsy material to obtain an unbiased estimate of blood vessel surface and volume densities. Biopsies of the nasal mucosa from the anterior 10 mm of an inferior turbinate were obtained from 18 subjects (15 males, 3 females with a mean age of 28.5 years [range: 17-54 years]), ten of whom had perennial allergic rhinitis, and eight control subjects. The mucosal tissue volumes were estimated by water displacement. Zamboni's-fixed cryostat sections (10 microns thick), stained with haematoxylin and eosin, were examined histologically. Computerised images of randomly selected tissue sections were analysed with point-counting and intercept-counting techniques to determine large blood vessel volume and surface densities, respectively. There were no significant differences between the volumes of tissue analysed from the control and rhinitic subjects (p = 0.35). The average volume density of the vessels was similar in the control group (6.17 +/- 1.41%) and the rhinitic group (7.8 +/- 5.59%; p = 0.38), but with a greater variability in the rhinitic group. Surface density estimations were 3.14 +/- 0.74 mm-1 in the control group and 3.10 +/- 1.41 mm-1 in the rhinitic group. Therefore, on average, the volume and surface densities of the cavernous blood vessels in rhinitis were unaltered and there was no evidence of vascular remodelling.

Adolescent↗

PubMed1994

A computer-assisted stereological quantification program: OpenStereo.

At present, the stereological assessment of histological sections is made possible by the use of manual counting techniques which estimate measurement parameters. These methods are tedious, time-consuming, and subject to operator error. This paper describes a UNIX-based computer program, OpenStereo, which was developed to facilitate the quantitative investigation of innervation and vascularity from histological sections. We designed OpenStereo to reduce operator error and increase the efficiency of stereological point counting for volume estimation and intercept counting for surface area analysis. The program was written in the C language for the Sun Workstation and uses the XView graphics user interface. Digital images, obtained by a variety of modalities, may be processed using stereological point counting, interceptions, planimetry, or thresholding techniques. The program displays selected images in a random fashion for analysis or processing and records the number of manually selected points or interceptions. Delineation of the reference space provides the computer with the data necessary to calculate volume or surface densities. The efficiency of OpenStereo was demonstrated by performing a pilot study on the quantification of innervation in the normal human colon and ileum. This stereological package benefits from the features of the X-windowing environment and has proved to be suitable for what has hitherto been a tedious and time-consuming task.

Adult↗

PubMed1994

Morphological and quantitative analyses of normal epidermal Langerhans cells using confocal scanning laser microscopy.

Confocal scanning laser microscopy (CSLM), when used in conjunction with computerized image processing systems, provides a powerful tool for morphological and quantitative analyses of biological tissues. In this study, normal human epidermal sheets were stained by an indirect immunofluorescence method using anti-CD1a monoclonal antibody. Positively stained epidermal Langerhans cells (LCs) were visualized using the Bio-Rad MRC-600 Confocal Imaging System. Images obtained from the confocal microscope were volumetrically rendered and quantitatively analysed using ANALYZE (Version 4.0) running on a Sun SPARC 2 Workstation. Normal epidermal LCs were shown to be large disc-like structures with five to nine long dendritic processes per cell, orientated with their flat surfaces parallel to the skin surface. LCs form a monolayer network of cells distributed evenly throughout the suprabasal layers of the epidermis, with no direct physical contact between dendritic processes. Mean LC density was estimated to be 582 per mm2 (95% confidence intervals, CI = 233-940), and mean cell volume was 612 microns3 (95% CI = 257-1020). LCs in sun-exposed sites were significantly lower in mean cell density, but larger in mean cell volume, than in covered sites. Mean surface area projected by LCs was estimated to be 26.8% (95% CI = 18.9-34.2), and this value did not show significant regional or individual variation. Our data support the notion that epidermal LCs are organized in such a way as to maximize their surface area for efficient trapping of antigens, and a reduction in LC density per unit area in sun-exposed sites is compensated for by an increase in the mean cell volume.

Cell Count↗