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Biomedical subjects

R Ford

Publications and source records attributed to R Ford.

At least 73 records · Page 4Linked to original sources
PubMed1996

Implantation of human colorectal carcinoma cells in the liver studied by in vivo fluorescence videomicroscopy.

In vivo fluorescence videomicroscopy (IVFM) was used to analyse the behavior of weakly and highly metastatic human colorectal carcinoma (CRC) cells during implantation in the liver. A highly metastatic human CRC cell line, CX-1, and a weakly metastatic line, Clone A, were double-labeled with rhodamine B isothiocyanate-dextran (Rd-Dx) to locate cells and with calcein AM to assess cell metabolic activity in an experimental metastasis model. Double-labeled CRC cells (2.0 x 10(6)) were injected into the spleens of groups of nude mice and the livers observed by IVFM over the next 72 h. CRC cells were implanted within 30 s after injection into either portal venules or the proximal third of hepatic sinusoids. Approximately 0.5% of CRC cells traversed the liver through portal-central venous shunts and implanted in the lung. The number of CX-1 cells in the liver was similar to that of Clone A cells during the first 12 h. However, more CX-1 cells than Clone A cells remained in the liver at 4 h and were in groups of 8-12 cells whereas only a few, single Clone A cells were detected in the liver at 72 h. Not all Clone A cells are committed to die within 4 h of implantation because cells harvested 4 h after hepatic implantation proliferated normally in vitro when removed from the hepatic microenvironment. Since the stress of mechanical deformation during implantation may cause differences in cell survival, CX-1 and Clone A cells were passed through filters with 8 microM pores in vitro at 10-15 cm of water pressure to recreate the trauma of hepatic implantation. Approximately 50% of both CX-1 and Clone A cells were lysed. Furthermore, both CRC lines remained metabolically active when co-cultivated with liver cells for at least 24 h in vitro. Thus, the difference in metastatic potential between the two CRC lines may reside in their response to the combination of mechanical implantation and subsequent growth in the liver parenchyma.

Animals↗
PubMed1995

Identification of B-cell growth factors (interleukin-14; high molecular weight-B-cell growth factors) in effusion fluids from patients with aggressive B-cell lymphomas.

The molecular basis of neoplastic B-cell growth is complex and poorly understood. Cytokines have been postulated to contribute to neoplastic cell growth, and many in vitro studies have confirmed this prediction, but little is known about the in vivo role of these growth factors. We have examined the production of interleukin-14 (IL-14) (high molecular weight [HMW], B-cell growth factor [BCGF]) by aggressive intermediate (diffuse large cell) lymphomas of the B-cell type non-Hodgkin's lymphoma (NHL-B) in four patients with lymphomatous effusions. In these studies, IL-14 was detected in the effusion fluids by Western blots and IL-14 mRNA was constitutively expressed in the freshly isolated lymphoma cells that also expressed the receptor for IL-14 (IL14R). Lymphoma B cells placed at low serum and cell density proliferated in vitro to either purified IL-14 or IL-14 derived from effusion fluids. Antibodies to IL-14 removed the growth-stimulating cytokine(s) from the effusions. Cell lines developed from these patients produced IL-14 in vitro and antisense oligos to IL-14 blocked their growth in vitro. Thus, autocrine or paracrine production of IL-14 may play a significant role in the rapid proliferation of aggressive NHL-B. Interrupting this pathway could be a useful goal of therapy for patients resistant to conventional chemotherapy.

Aneuploidy↗
PubMed1995

Expression, purification, and use as an antigen of recombinant sugarcane mosaic virus coat protein.

A high titre (1:10,000) antiserum was raised in a rabbit against the coat protein of sugarcane mosaic potyvirus (SCMV), by injecting a preparation of recombinant coat protein purified from a fusion protein expressed in E. coli. The fusion protein consisted of the MalE maltose binding protein (MBP) and the viral coat protein separated by the protease factor Xa cleavage site. The fusion protein was encoded by the plasmid pMAL-cCPM, which was constructed by cloning a modified coat protein gene to the 3' end of the MBP/factor Xa coding region. The coat protein gene was modified by site-directed mutagenesis so that the ATG start codon in the original construct was replaced by the codon AGC, deleting the NcoI restriction site (C/CATGG) and creating a unique Eco47III site (AGC/GCT). Endonuclease restriction with Eco47III resulted in a DNA fragment with GCT as the first three nucleotides. This triplet encodes alanine, which is the proposed N-terminal amino acid residue of the mature native coat protein. This modified coat protein coding region was ligated directly behind the nucleotide code for the amino acid recognition sequence for factor Xa. Expression was induced with IPTG and the recombinant fusion protein was extracted from the bacterial lysate by amylose resin column affinity chromatography and the two domains separated by factor Xa proteolysis. The coat protein was then purified from the maltose binding protein by ion exchange chromatography in buffer containing 6 M urea. A highly purified sample which contained 150 micrograms of both full-length and truncated coat proteins, was recovered from a litre of bacterial broth. The antiserum reacted with native coat protein in SCMV-infected sugarcane, and with recombinant coat proteins expressed in E. coli and sugarcane protoplasts with little or no cross-reaction with sugarcane proteins.

Amino Acid Sequence↗
PubMed1995

Housing aspirations and migration in later life: developments during the 1980s.

"This paper tests hypotheses concerning the differentiation of early and late old age in the United Kingdom with reference to housing preferences and requirements and their translation into migration. Evidence is drawn from the 1991...census and from a representative sample of elderly people in SE England. The sources demonstrate the continued elaboration of long-distance, metropolitan-decentralizing migrations around the age of retirement. Also shown are relatively high rates of residential mobility among people in their seventies and eighties. Most of their migrations are short distance, but nonetheless with a net redistributional effect that sustains urban decentralization at the oldest ages. There is no evidence of significant return migration to London at advanced ages. From the survey responses, distinctive housing dissatisfactions are identified in early and late retirement, but neither set exactly matches expressed motivations for moves."

Adult↗