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M O'Rand

Publications and source records attributed to M O'Rand.

6 recordsLinked to original sources

Cloning and sequencing of human Eppin: a novel family of protease inhibitors expressed in the epididymis and testis.

In this report we describe the discovery of Eppin (Epididymal protease inhibitor), a gene on human chromosome 20 expressing three mRNAs encoding two isoforms of a cystine-rich protein containing both Kunitz-type and WAP-type four disuffide core protease inhibitor consensus sequences. Analysis of Eppin's genomic sequence from chromosome 20q12-13.2 predicts the existence of all three splice variants of Eppin and that all the exons conform to the AG/GT splicing rule. The presence of single bands on a Southern blot of human genomic DNA suggests that Eppin is a single copy gene. TATA box transcription initiation sites are present for both of the different Eppin 5' UTRs and examination of the promoter region 1800 bp upstream of the start codon revealed a number of putative transcription enhancer binding sites typical of genes expressed in the epididymis or testis. Northern blot and tissue specific PCR data indicate Eppin-1 is expressed only in the testis and epididymis; Eppin-2 is expressed only in the epididymis and Eppin-3 only in the testis. Antiserum prepared against recombinant EPPIN recognizes several strong bands on Western blots of human epididymal extracts from the caput and corpus regions. Immunohistochemistry indicates a strong pattern of expression by the ciliated cells of the efferent ducts and strong staining of ejaculated spermatozoa. Eppin represents the first member of a family of protease inhibitors characterized by dual inhibitor consensus sequences, both WAP-type and Kunitz-type consensus sequences. A second family member is predicted to exist on chromosome 20 approximately 4 kb downstream from Eppin's exon I, which has two WAP-type sequences and one Kumtz-type consensus sequence.

Alternative Splicing↗

Automated image-based cytometry with fluorescence-stained specimens.

The combination of digitized microscopy, algorithms for object recognition and fluorescent labeling is a promising approach for reliable, quick, automated and cost-effective screening of clinical specimens. We describe two conceptually different algorithms for detecting objects in fluorescence microscopic images. One, which is partially automated, compares a mask that represents a typical object with every position in the image; the other, which is fully automated, calculates threshold intensities to segment the image into regions of objects and background. Applications of the algorithms in conjunction with a prototype image-based cytometer are demonstrated for determining the DNA ploidy distribution of cultured human endometrial cells and determining the DNA ploidy distribution and the fraction of cells expressing the E6 antigen of human papilloma virus serotypes 16 and 18 in a PAP smear. The encouraging results from this study suggest that automated image-based cytometry utilizing fluorescent stains will be a valuable asset for clinical screening.

Algorithms↗

Automated fluorescence image cytometry. DNA quantification and detection of chlamydial infections.

Digitized fluorescence microscopy in conjunction with automated image segmentation is a promising approach for screening clinical specimens quickly and reliably. This paper describes the hardware and software of a prototype image-based cytometer that can identify fluorescent objects, discriminate true objects from artifacts and divide overlapping pairs of objects. The use of this image cytometer is discussed for: (1) the measurement of the DNA ploidy distribution of isolated mature rat liver nuclei labeled with 4',6-diamidine-2-phenylindole; (2) the comparison of the DNA ploidy distributions of the same samples measured by image cytometry (ICM) and flow cytometry (FCM); and (3) the quantification of chlamydial infection by double labeling cells with antichlamydiae antibody and Hoechst 33258 for nuclear DNA analysis. Ploidy distributions measured by the automated image cytometer compared favorably to those obtained by FCM. All pairs of overlapping nuclei were automatically detected by an additional computer algorithm, and those pairs that were clearly more than one nucleus by visual inspection were correctly divided. The irregular morphology of the chlamydiae-infected cells meant that 26% of them were not correctly identified in the fluorescein-stained images (as judged by manual inspection), but all cells were nevertheless detected correctly from the images of the Hoechst-stained samples. Automated fluorescence ICM yielded results similar to those obtained with FCM and had the additional benefit of maintaining cell and tissue architecture while preserving the opportunity for subsequent manual inspection of the specimen.

Algorithms↗

Semen parameters and fertilization of human oocytes in vitro: a multivariable analysis.

Semen parameters in 195 couples undergoing in vitro fertilization and embryo transfer were studied using multivariable analysis. Semen parameters that correlated most closely with reduced ability to fertilize apparently mature oocytes were a slow rate of foreward progression of sperm and the presence of excess numbers of white cells in semen. In men with semen parameters within the normal range, the hamster egg penetration assay (HEPA) test did not add additional predictive power. In men with suspected semen abnormalities, however, a low attachment rating added some, but minimal, predictive value. None of the predictive methods reported thus far in this or other studies offers sufficient accuracy to reliably identify the men who will prove infertile for in vitro fertilization treatment.

Analysis of Variance↗

Positive correlation between body weight, length of human menopausal gonadotropin stimulation, and oocyte fertilization rate.

One hundred four normally cycling women were treated with fixed low-dose human menopausal gonadotropin (hMG) (2 ampules/day) in preparation for oocyte aspiration for in vitro fertilization. The response rate was related to age, weight, and the ratios weight/height2 and weight/height. The required dose of hMG was related to total body weight, but not to age or either of the weight/height ratios. In patients who required fewer than 5 days of hMG (rapid responders), a significantly higher number (P less than 0.02) of oocytes were harvested, compared with slow responders. However, a smaller percentage of the oocytes from rapid responders fertilized (P less than 0.003) and resulted in a reduced rate of embryo transfer. The difference in pregnancy rates was not statistically significant. The results of the study suggest that patients undergoing in vitro fertilization who weigh less than 55 kg may benefit from treatment with a lower dose of hMG to prolong the stimulation cycle.

Adult↗