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Biomedical subjects

T M Morris

Publications and source records attributed to T M Morris.

14 recordsLinked to original sources
PubMed1995

Inhibition of organ invasion by the matrix metalloproteinase inhibitor batimastat (BB-94) in two human colon carcinoma metastasis models.

The effect of the matrix metalloproteinase inhibitor batimastat was evaluated in two human colorectal cancer metastasis models involving: (a) the liver-invasive tumor C170HM2 and (b) the lung-invasive tumor AP5LV, both of which have been shown to express the M(r) 72,000 type IV collagenase. Batimastat at concentrations between 0.01 and 3.0 micrograms/ml had no direct cytotoxic effects on the in vitro growth of the cell lines. In the liver-invasive tumor model, batimastat administered i.p. from day 10 to termination of the therapy (day 39) at 40 mg/kg reduced both the mean number of liver tumors (35% of vehicle-treated control; P < 0.05) and the cross-sectional area of the tumors (43% of vehicle-treated control; P < 0.05). In the lung-invasive tumor model, batimastat administered daily (40 mg/kg i.p.) significantly reduced tumor weight within the lung (72% of vehicle-treated control; P < 0.05) but did not significantly affect nodule number. In the latter model, in which the take rate was unaffected, tumor cells were introduced into the lateral tail vein, and lung localization may have been a physical phenomenon not involving invasion. In the former model, tumor cells were introduced directly into the peritoneal cavity, and from there the cells adhered to and invaded the liver capsule. Because the take rate is significantly reduced, it may be that the matrix metalloproteinases are involved in this process. Batimastat may be a therapeutic modality for the treatment of colorectal cancer metastasis.

Animals↗
PubMed1995

Anti-gastrin antibodies raised by gastrimmune inhibit growth of the human colorectal tumour AP5.

The neutralising ability of rabbit anti-gastrin-17 (G17) antiserum raised by Gastrimmune, an immunogen constructed of the N-terminal portion of human G17 conjugated to diptheria toxoid (DT), was evaluated. The anti-serum (denoted anti-G17: DT) was shown to displace 125[I] G17 from the gastrin receptors on AR42J cells. The therapeutic effect of the rabbit anti-G17:DT anti-serum was evaluated on a freshly derived human colorectal cancer cell line, AP5, which was shown to express both gastrin receptors and gastrin immunoreactivity as assessed by immunocytochemistry. Rabbit anti-G17:DT anti-serum was shown to block basal in vitro growth of AP5 cells when used at an antigen binding capacity of 3.75 x 10(-9) M. The same dilution of anti-serum completely reversed growth stimulated by human G17 at concentrations of 1 x 10(-10) and 1 x 10(-9) M but did not inhibit growth at 1 x 10(-8) M G17. When AP5 was grown as a xenograft in nude mice, the sensitivity to the proliferative effect of human G17 was maintained. In addition, the basal growth of AP5 xenografts was significantly reduced by i.v. infusion of rabbit anti-G17:DT anti-serum when compared to treatment with rabbit anti:DT control anti-serum. Thus anti-G17:DT antibodies raised by Gastrimmune may be of clinical value in gastrin-sensitive tumours.

3T3 Cells↗
PubMed1991

Influence of recombinant tumour necrosis factor alpha on blood flow and antibody localisation in human tumour xenografts in nude mice.

Mice with s.c. grafts of gastric carcinoma MKN45 or osteosarcoma 788T were injected i.v. with recombinant tumour necrosis factor alpha (rTNF alpha) and tumour blood flow rates were determined 4 h later as a fraction of the cardiac output g tissue-1. With MKN45, the tumour blood flow rate was significantly reduced from a mean of 1.86% cardiac output g-1 to 0.84% and 0.65% with 50 and 200 micrograms kg-1 rTNF alpha respectively. With 788T, the tumour blood flow rate was reduced at 50 micrograms kg-1 rTNF alpha from 1.13% cardiac output g-1 to 0.56%. There were essentially no changes in blood flow rates in other organs. The effect of rTNF alpha on localisation of monoclonal antibodies into these xenografts were examined. When a single dose of rTNF alpha (50 micrograms kg-1) was given at the same time as labelled NCRC-2 antibody there was a significant reduction in localisation into 788T osteosarcoma xenografts. In other tests, mice were injected daily for 3 days with 50 micrograms kg-1 rTNF alpha. They were injected i.v. with monoclonal antibody 4 h after the first injection and dissected on the 4th day. With 788T there was a small but not statistically significant reduction in the absolute amount of NCRC-2 antibody localising in tumour, although this reduction was greater when results were expressed as tumour-to-blood ratios. With MKN45 xenografts, treatment with rTNF alpha had little effect on tumour localisation of an anti-(carcinoembryonic antigen) monoclonal antibody (NCRC-24). These studies show that TNF can be administered so as to reduce tumour blood flow and with little effect on tumour localisation of antibody, suggesting that combination therapy with TNF and antibodies or their immunoconjugates is feasible. Other studies have suggested that TNF can increase antibody localisation into tumours, but this was not seen here, and in some cases administration could reduce tumour localisation. It appears that this method of enhancing antibody localisation may be critically dependent on scheduling, and therefore it may not be extensively applicable.

Animals↗
PubMed1990

Culturally sensitive family assessment: an evaluation of the family assessment device used with Hawaiian-American and Japanese-American families.

This article reports the results of a study of the McMaster Family Assessment Device (FAD) used with samples drawn from two non-Anglo ethnic groups: Hawaiian-Americans and Japanese-Americans living in Hawaii. The results showed that the FAD appeared to make appropriate assessments of Hawaiian-American study participants' families and inappropriate assessments of Japanese-American study participants' families. Results also suggested that cultural norms regarding family functioning may vary according to socioeconomic status. FAD modifications are suggested.

Asian↗
PubMedDate not supplied

Opening of the blood-brain barrier by intravenous contrast media in euvolemic and dehydrated rabbits.

It has been suggested that intravenous injections of hypertonic contrast media when used in computed tomography and digital subtraction angiography might raise plasma osmolality sufficiently to open the blood-brain barrier (BBB). The current investigation establishes the threshold of plasma osmolality that causes the the opening of the BBB in euvolemic and dehydrated rabbits. Euvolemic rabbits were allowed food and water ad libitum. Dehydrated rabbits received 4.0 mg/kg of furosemide intramuscularly and were deprived of water for 72 hours. Meglumine/sodium diatrizoate 76 per cent (n = 28) or mannitol 20 per cent (n = 12) was administrated intravenously, at a rate of 25 mmol/kg body weight/hour for 2, 3 or 4 hours. Plasma osmolality, blood iodine concentration, blood pressure, heart rate and hematocrit were assessed at regular intervals. Evans blue and 99Tcm-DTPA were used simultaneously as tracers for BBB opening. Rating of BBB opening with 99Tcm-DTPA correlated well with Evans blue staining (r = 0.863, p less than 0.001; n = 42). BBB opening was related to plasma osmolality and was similar for both contrast media and mannitol. Widespread BBB opening occurred above 400 mmol/kg while focal BBB opening occurred above 370 mmol/kg. Dehydration per se increased plasma osmolality but did not reduce the threshold for BBB opening.

Animals↗