Search PubMed⌕ Search

Biomedical subjects

B D Evans

Publications and source records attributed to B D Evans.

At least 55 records · Page 3Linked to original sources
PubMed1984

Prevention of acute deaths in mice after very high dose cyclophosphamide by divided dose schedule.

Very high dose cyclophosphamide (Cy) (500-600 mg kg-1) given by single bolus i.p. injection in mice caused acute deaths in all animals within 48 h of treatment (0/10 survivors). These acute deaths were abolished or very significantly reduced if Cy was administered in divided dosage over 8 h (10/10 survivors) or 12 h (14/15 survivors). The effect was maintained at doses of up to 600 mg kg-1 administered in divided dosage over 24 h (15/15 survivors). In 2 human small cell carcinoma xenografts anti-tumour efficacy was not diminished by divided dosage. In both xenografts tumour growth delay was enhanced, although not significantly so, when treated with divided dosage compared with single dose, and in one of the xenografts 3 complete remissions were achieved with divided dosage compared with none after single dosage. It is postulated that the underlying mechanism concerns diminished cardiotoxicity. These results may have significance in clinical studies investigating very high dose Cy.

Animals↗
PubMed1983

Predictors of favorable outcome following naltrexone treatment.

In order to determine the type of patient most likely to benefit from opiate antagonist therapy, a series of multivariate regression analyses were performed on a sample of male veterans who completed induction on naltrexone. Patient background characteristics, demographic factors and during-treatment variables were used to predict outcome measured at 1-month follow-up. Employment at the start of naltrexone and length of naltrexone therapy were significantly related to better outcome at 1-month follow-up. Treatment duration was clearly the best outcome predictor. The finding that at least 30 days of naltrexone therapy was necessary for significant improvement at 1-month follow-up but that longer periods of treatment were not necessarily associated with greater gains suggests that treatment can be limited and still be relatively successful. A second set of analyses attempted to discover patient characteristics predictive of longer treatment duration. Results showed that patients who were employed and/or married at the start of naltrexone therapy were more likely to stay in treatment longer. Similar results have been obtained by others suggesting that these patients have the best family and social supports to sustain a positive treatment outcome. In addition, they may also be more 'motivated' since they have the most to lose personally and financially by readdiction.

Employment↗
PubMed1983

High dose cyclophosphamide treatment of human oat cell xenografts in immune deprived mice.

Immunodeprived mice survived a high, otherwise lethal dose of cyclophosphamide (Cy) provided they had been "primed" with a low dose (50 mg kg-1) of the drug 4 days earlier. These combinations were then tested on 2 oat cell xenograft lines (which are known to reproduce the chemotherapeutic responses of the parent tumours) grown in immunodeprived mice. In the treatment of the first oat cell xenograft, 200 mg kg-1 Cy produced a growth delay of 34 days in the unprimed group and 45 days in the primed group. At a dose of 300 mg kg-1 a growth delay could not be assessed in the control group as 16/17 of these unprimed mice bearing this xenograft died. However, 14/22 tumours went into complete remission in this group before death occurred. In contrast only 3/16 deaths occurred in the group of mice that were primed before receiving the same challenge dose. In these animals 19/26 tumours went into complete remission and were still completely absent when the experiment was terminated at 60 days. Using the second oat cell xenograft, 300 mg kg-1 Cy produced a growth delay of 27 days. However, at this dose level all the animals were dead by day 46. In mice which had been primed with 50 mg kg-1 Cy 4 days before the administration of 300 mg kg-1 a growth delay of 32 days was achieved and 2/9 animals were alive at day 60. This study shows that priming allows larger doses of Cy to be given to immunodeprived mice bearing human tumour xenografts than would normally be tolerated and that the priming does not alter the anti-tumour efficacy of the large challenge dose as measured by tumour growth delay or complete remission rate. As the tumours were human in origin it raises the question whether high dose cyclophosphamide therapy and priming have a role to play in the treatment of patients with oat cell carcinoma.

Animals↗
PubMed1983

Phase II study of JM8, a new platinum analog, in advanced ovarian carcinoma.

A phase II study of JM8, an analog of cisplatin, has been carried out in 36 patients with advanced ovarian carcinoma. Thirty-three of these patients had recurrent carcinoma and had been heavily pretreated, either with cytotoxic drugs alone (28 patients) or with cytotoxic drugs and radiotherapy (five patients). All patients had previously received cisplatin, either alone or as part of a combination, and some of them had previously been treated with as many as four different chemotherapy regimens. In addition, three patients with stage III ovarian carcinoma were treated with JM8 as first-line therapy. Twenty-eight of the 33 pretreated patients were evaluable for response, and five partial and two complete remissions were achieved. Of the seven responders, four had previously been shown to be completely resistant to cisplatin, and a fifth had initially responded to, but subsequently relapsed, while receiving cisplatin. Renal, aural, and neurotoxic effects were less than would have been expected with cisplatin, but hematologic toxic effects were common, with a wbc count of less than 2000 X 10(9)/L recorded in six patients, and a platelet count of less than 50,000 X 10(9)/L recorded in eight patients.

Antineoplastic Agents↗
PubMed1978

Determination of citrinin in corn and barley.

A method is described for determining citrinin in corn and barley. The initial extraction uses an aqueous acidified acetonitrile solution, and the resulting solution is partially purified by several partition steps. Citrinin is determined by using either high pressure liquid chromatography (HPLC) or thin layer chromatography (TLC). For HPLC, the extract is injected on a reverse phase column, eluted with either 0.25N H3PO4-methanol (45 + 55) or 0.25N H3PO4-acetonitrile (50 + 50), and detected by fluorescence (excitation 325--385 nm, emission above 451 nm). Recovery of added citrinin from corn by this method is 60--87% at levels of 50--4000 microgram/kg. For TLC, the chromatographic plates are impregnated with oxalic acid by dipping them in an oxalic acid-methanol solution before spotting and development. Recovery of added citrinin from corn, using TLC, is 40--100% at levels of 50--40000 microgram-kg.

Benzopyrans↗