PubMed Health⌕ Search

Biomedical subjects

C Hilliard

Publications and source records attributed to C Hilliard.

5 recordsLinked to original sources

Regional localization of over 300 loci on human chromosome 22 using a somatic cell hybrid mapping panel.

A somatic cell hybrid panel, consisting of 25 cell lines, has been developed to localize loci subregionally on chromosome 22. Over 300 markers in the form of STSs or hybridization probes have been assigned to one of 24 unique regions or "bins" using this panel. This ordered collection of markers will aid in the assembly of physical maps and contigs of chromosome 22 and assist in positional cloning of disease loci mapped to chromosome 22.

Animals↗

A region of consistent deletion in neuroblastoma maps within human chromosome 1p36.2-36.3.

Deletion of the short arm of human chromosome 1 is the most common cytogenetic abnormality observed in neuroblastoma. To characterize the region of consistent deletion, we performed loss of heterozygosity (LOH) studies on 122 neuroblastoma tumor samples with 30 distal chromosome 1p polymorphisms. LOH was detected in 32 of the 122 tumors (26%). A single region of LOH, marked distally by D1Z2 and proximally by D1S228, was detected in all tumors demonstrating loss. Also, cells from a patient with a constitutional deletion of 1p36, and from a neuroblastoma cell line with a small 1p36 deletion, were analyzed by fluorescence in situ hybridization. Cells from both sources had interstitial deletions of 1p36.2-36.3 which overlapped the consensus region of LOH defined by the tumors. Interstitial deletion in the constitutional case was confirmed by allelic loss studies using the panel of polymorphic markers. Four proposed candidate genes--DAN, ID3 (heir-1), CDC2L1 (p58), and TNFR2--were shown to lie outside of the consensus region of allelic loss, as defined by the above deletions. These results more precisely define the location of a neuroblastoma suppressor gene within 1p36.2-36.3, eliminating 33 centimorgans of proximal 1p36 from consideration. Furthermore, a consensus region of loss, which excludes the four leading candidate genes, was found in all tumors with 1p36 LOH.

Base Sequence↗

Gene expression in clonally derived cell lines produced by in vitro transformation of rat fetal hepatocytes: isolation of cell lines which retain liver-specific markers.

The pattern of gene expression in fetal hepatocytes transformed in culture with a hepatocarcinogen (FRL cells) is studied with respect to a range of markers which are either developmentally regulated and/or shown to be expressed at high levels in hepatoma cells. The relative abundance of the respective mRNAs is determined and immunocytochemistry is used to detect the respective proteins in cultured cells. When compared with its normal counterpart, FRL cells retain the expression of transferrin, alpha 1-acid glycoprotein, gamma-glutamyltranspeptidase, and tyrosine aminotransferase at near normal levels, while expression of the liver-specific isoenzymes of pyruvate kinase (L form) and aldolase (B form) is reduced. The cell lines are different in that they fail to express albumin, alpha-fetoprotein, thiostatin and alpha 2-macroglobulin, and they express high levels of M2-pyruvate kinase and aldolase A, markers often found in abundance in hepatoma cells. Therefore transformation has resulted in different effects on different genes. Furthermore, it is of interest to find that the cells coexpress both forms of the pyruvate kinase isoenzymes which does not occur in the normal developing hepatocyte. These results indicate that it is possible to use this model to study changes which accompany transformation of fetal rat hepatocytes. The resulting cell lines have a stable phenotype and retain the changes which result from transformation even after extended passaging. This facilitates comparisons between the precursor cell and the tumor cell, both of which can be maintained under controlled conditions which exist in culture.

Animals↗

Hormonal profiles and embryo quality in women with severe endometriosis treated by in vitro fertilization and embryo transfer.

A study was undertaken comparing the outcomes of 30 women with infertility due to untreated severe (grade IV) pelvic endometriosis with a comparable series of 28 women whose infertility was caused solely by irreversible tubal disease. There were no significant differences in either the follicular phase or luteal phase hormonal profiles of estradiol and progesterone, but there was a significantly reduced pregnancy rate in those women with severe endometriosis. In part, this was due to the recovery of fewer oocytes from the endometriosis patients (P less than 0.001) despite the fact that the peak estradiol levels and ovarian accessibility were similar in the two groups. However, there were no significant differences in the proportion of oocytes that fertilized or the number that demonstrated normal embryo growth and high-grade embryo quality. There also appears to be an implantation inhibitory factor in patients with severe endometriosis as the pregnancy rate/embryo transferred and number of gestational sacs identified/embryo transferred were significantly reduced (P less than 0.05).

Embryo Transfer↗

Using structured reflection on a critical incident to develop a professional portfolio.

This article demonstrates reflective practice by examining a critical incident that took place at a children's burns unit. The development of reflective skills is documented using a method of structured reflection. The concepts of aesthetics, personal knowing, empirics and ethics are considered to reflect on the critical incident. Reflection is considered in the context of developing a portfolio to analyse and demonstrate learning in practice.

Child↗