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C J Rutty

Publications and source records attributed to C J Rutty.

10 recordsLinked to original sources
PubMed1996

The middle-class plague: epidemic polio and the Canadian state, 1936-37.

During the pre-Salk era, paralytic poliomyelitis was one of the most feared diseases of twentieth-century North America. This perception, held most strongly by the middle class-- polio's principal target--shaped a unique Canadian response to it based on comprehensive, standardized, and unconditional programs of "state medicine" at the provincial level. Of Canada's four major waves of provincial polio epidemics, the second struck Ontario to an unprecedented degree in 1937, generating a similarly unprecedented response from the Ontario government in its control, treatment, hospitalization, and aftercare measures. As this article discusses, the severity of this epidemic led the provincial, and other Canadian public health authorities, to face a central question: How far should governments be compelled to go to ensure the advantages of modern treatment for their people? This article helps place the social impact of, and political and scientific response to, epidemic polio within the context of Canada's evolving public health and state medicine infrastructure at the time.

Canada↗
PubMed1993

Synthesis and cytotoxicity of potential tumor-inhibitory analogues of trimelamol (2,4,6-tris[(hydroxymethyl)methylamino]-1,3,5-triazine) having electron-withdrawing groups in place of methyl.

In exploring the structural features which determine the antitumor activity of 2,4,6-tris-[(hydroxymethyl)methylamino]-1,3,5-triazine (trimelamol, 1), we have synthesized analogues in which the methyl groups have been replaced by the electron-withdrawing substituents 2,2,2-trifluoroethyl (5), propargyl (13), and cyanomethyl (15) via the respective tris(alkylamino)triazines 3, 12, and 14. Three mono[(hydroxymethyl)amino]triazines (4, 7, and 10) were also prepared. All the new tris(hydroxymethyl) derivatives showed cytotoxicities toward a variety of experimental rodent and human ovarian tumor cell lines similar to those shown by 1, the cyanomethyl analogue (15) having the most favorable profile. Mono(hydroxymethyl) derivatives (4 and 7) were ca. one-third as toxic. The new tris(hydroxymethyl) analogues were more stable to aqueous hydrolysis than was 1. Half-life (pH 7.5) values were, for 1, 120 min, for 5, 690 min, for 13, 450 min, and for 15, 275 min, but at pH 2.0, 15 (t1/2 350 min) was the most stable. This cyanomethyl analogue was also the most water-soluble, being comparable to 1 whereas 5 and 13 were poorly soluble.

Animals↗
PubMed1989

Phase I trial and pharmacokinetics of trimelamol (N2,N4,N6-trihydroxymethyl-N2,N4,N6-trimethylmelamine).

Trimelamol is an analogue of hexamethylmelamine and pentamethylmelamine which does not require metabolic activation and is sufficiently soluble to allow parenteral administration. A Phase I trial has been performed at the Royal Marsden Hospital in which two schedules of administration have been evaluated, a single i.v. infusion repeated every 3 weeks and 3 daily doses repeated every 3 weeks. Pharmacokinetic analysis was performed at all dose levels on both schedules and a linear correlation was demonstrated between dose and area under the curve. Myelosuppression was dose limiting for single dose administration with a maximum tolerated dose of 2400 mg/m2. Median leukocyte nadirs at 1800, 2100, and 2400 mg/m2 were 3.2, 2.6, and 1.5 x 10(9)/liter. Thrombocytopenia and anemia also occurred but were not dose limiting. Doses greater than 1500 mg/m2 caused WHO grade 3 nausea and vomiting but no acute sedation. Three day administration appeared to be less myelosuppressive, giving a maximum tolerated dose of 1000 mg/m2. Median leukocyte nadirs at 800, 900, and 1000 mg/m2 daily for 3 days were 3.0, 2.3, and 1.5 x 10(9)/liter. Nonhematological toxicities were also less marked on the fractionated schedule. Antitumor effects were observed including 1 complete and 9 partial responses. Demonstration of activity in ovarian cancer has led to further evaluation in this disease using the 3-day schedule at a dose of 800 mg/m2 daily for 3 days.

Adult↗
PubMed1986

Preclinical toxicology, pharmacokinetics and formulation of N2,N4,N6-trihydroxymethyl-N2,N4,N6-trimethylmelamine (trimelamol), a water-soluble cytotoxic s-triazine which does not require metabolic activation.

N2,N4,N6-Trihydroxymethyl-N2,N4,N6-trimethylmelamine (Trimelamol) is a water-soluble synthetic s-triazine which, unlike hexamethylmelamine (HMM) and pentamethylmelamine (PMM), does not require metabolic activation. The physico-chemical characteristics of Trimelamol were studied with the aim of overcoming the problems of chemical instability, low solubility and polymerisation which had hindered the development of the drug for clinical use. Trimelamol had similar activity to PMM against the murine PC6 plasmacytoma, but enhanced activity with respect to PMM against the Walker 256 carcinosarcoma in the rat, a species which metabolizes PMM less efficiently. Pharmacokinetic studies in mouse, rat and man did not show the major species differences characteristic of PMM. The drug exhibited similar toxicity to PMM against rodents, but had virtually no neurotoxicity. The potential advantages of Trimelamol over previously tested melamines are discussed.

Altretamine↗
PubMed1986

Low central nervous system penetration of N2,N4,N6,-trihydroxymethyl-N2,N4,N6,-trimethylmelamine (Trimelamol): a cytotoxic s-triazine with reduced neurotoxicity.

Trimelamol (N2,N4,N6-trihydroxymethyl-N2,N4,N6-trimethylmelamine) is an analogue of pentamethylmelamine (PMM). In early clinical trials PMM failed to show significant anti-tumour activity in man which was attributed to poor metabolic activation. Trimelamol does not require activation and is therefore expected to be more active in man. PMM caused dose-limiting emesis and sedation whereas Trimelamol is much less neurotoxic in rodents. The relative penetration of PMM and Trimelamol into mouse brain has therefore been examined. Mice receiving PMM at 90 mg kg-1 i.p. were found to have high concentrations of the drug in the CNS compared to plasma (mean brain/plasma ratio 1.04) whereas animals receiving Trimelamol had consistently low CNS concentrations (mean brain/plasma ratio 0.08). This difference did not correlate with plasma protein binding which is greater for PMM (68.2%) than for Trimelamol (17.5%). However, it does appear to be related to lipophilicity. In Phase I clinical trial Trimelamol has proved much less emetic than PMM and causes no acute sedation. It is likely that this reduction in toxicity may be explained by the relatively poor ability of Trimelamol to enter the CNS.

Altretamine↗
PubMed1982

The comparative pharmacokinetics of pentamethylmelamine in man, rat, and mouse.

The pharmacokinetics of pentamethylmelamine (PMM) have been investigated in mouse (Balb C-, CBA/LAC, nude), rat (Wistar), and man. In all three species, PMM was extensively demethylated to N2,N2,N4,N6-tetramethylmelamine and N2,N4,N6-trimethylmelamine, although marked species differences in the rate of metabolism were observed. PMM metabolism was more rapid in the mouse (plasma t1/2 = less than 15 min) than in the rat (plasma t1/2 = 40 min), and slower in man (plasma t1/2 = 102 min) than in either mouse or rat. Furthermore, the peak plasma concentrations of N-methylolmelamines, intermediates generated during oxidative N-demethylation, were correspondingly higher in the mouse (563-773 microM) than in the rat (211 microM), whilst in man they were undetectable (less than 50 microM). In view of the highly cytotoxic nature of N-methylolmelamines, we conclude that these pharmacokinetic differences may be related to the antitumour effectiveness of PMM in mouse, rat, and man.

Altretamine↗
PubMed1980

In vitro cytotoxicity of the methylmelamines.

Hexamethylmelamine (HMM) and a number of its derivatives are toxic to PC6 plasmacytoma cells in vitro. However, there is no correlation between in vitro cytotoxicity and activity against this tumour in vivo. N-Methylolmelamines are significantly more toxic than HMM itself. These compounds break down to release formaldehyde which is itself a highly cytotoxic agent. Pentamethylmonomethylolmelamine rapidly inhibits the growth of PC6 cells in culture, whereas HMM and pentamethylmelamine (PMM) require prolonged contact with the cells in order to exert a cytotoxic effect. HMM and its metabolites are also toxic to a number of other cell lines. The toxicity of the N-methylols to cultured L1210 leukaemia and Walker 256 ascites cells appears to be due entirely to formaldehyde release, whereas in PC6 cells the methylols appear to be acting more selectively.

Altretamine↗