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T Smythe

Publications and source records attributed to T Smythe.

12 recordsLinked to original sources

Calcium and endoplasmic reticulum dynamics during oocyte maturation and fertilization in the marine worm Cerebratulus lacteus.

To monitor calcium and endoplasmic reticulum (ER) dynamics during oocyte maturation and fertilization, oocytes of the marine worm Cerebratulus lacteus were injected with the calcium-sensitive indicator calcium green dextran and/or the ER-specific probe "DiI." Based on time-lapse confocal imaging of such specimens, prophase-arrested immature oocytes failed to develop normally after insemination and typically produced non-wave-like calcium transients that were lower in amplitude and less persistent than the wave-like oscillations observed during fertilizations of mature oocytes. Accordingly, the ER of DiI-loaded immature oocytes lacked an obvious substructure, whereas ER clusters, or "microdomains," began to form in maturing specimens at about the time that these oocytes became competent to undergo normal fertilization-induced calcium dynamics and cleavage. The ER microdomains of mature oocytes typically reached widths of 1-8 micrometer and disappeared approximately 1 h after fertilization, which in turn coincided with the termination of the calcium oscillations. Collectively, these findings indicate: (i) changes in ER structure are temporally correlated with the onset and cessation of the calcium oscillations required for subsequent cleavage, and (ii) such ER reorganizations may play an important role in early development by enabling mature oocytes to generate a normal calcium response.

Animals↗

5-Fluorouracil, doxorubicin, and mitomycin (FAM) combination chemotherapy for advanced gastric cancer.

Sixty-two patients with advanced measurable gastric cancer were treated with a combination chemotherapy program of 5-fluorouracil, doxorubicin, and mitomycin (FAM). Forty-two percent of patients achieved an objective partial response. The median duration of remission was 9 months and the median survival for responding patients, 12.5 months. The median survival for nonresponding patients was 3.5 months; all patients were dead by 8 months after initiation of therapy. The median survival of all 62 patients treated with FAM was 5.5 months. An analysis of possible prognostic variables including initial performance status, resectability of the primary gastric tumor, and histologic differentiation of the neoplasm failed to account for differences in patient response and survival. The FAM regimen was well tolerated, producing only moderate bone marrow suppression. These results show that patients with metastatic gastric cancer can be effectively palliated with FAM chemotherapy. The efficacy of this regimen should now be tested in patients with less advanced stages of this disease.

Adenocarcinoma↗

5-fluorouracil, adriamycin, and mitomycin-C (FAM) combination chemotherapy in the treatment of advanced gastric cancer.

Thirty-six patients with advanced measurable gastric cancer were treated with a new combination chemotherapy program consisting of 5-fluorouracil, Adriamycin and mitomycin-C (FAM). Fifty percent of patients achieved an objective partial response. The median duration of remission was 9.5 months and the median survival for responding patients was 13.5 months, with 2 remaining alive at 14 and 26 months. The median survival for nonresponding patients was 3.0 months and all were dead by 6 months after initiation of therapy. The median survival of all 36 patients treated with FAM was 5.5 months. An analysis of possible prognostic variables including initial performance status, resectability of the primary gastric tumor and histologic differentiation of the neoplasm failed to account for differences in patient response and survival. The FAM regimen was well tolerated, and produced only moderate bone marrow suppression. These results demonstrate that some patients with advanced gastric cancer can be effectively palliated with FAM chemotherapy. Phase III trials are warranted to assess the effect of the FAM regimen on the survival of patients with advanced gastric cancer.

Adenocarcinoma↗

A phase II trial of ftorafur: adriamycin and mitomycin-C (FAM II) in advanced gastric adenocarcinoma.

Fifteen patients with advanced gastric cancer were treated with the combination of Ftorafur, Adriamycin and mitomycin-C (FAM II). Three patients showed partial responses, in five the disease remained stable for at least 3 months and seven showed progression while on treatment. All responding patients showed survival in excess of 12 months. Hematologic toxicity was of only moderate severity. Median white count nadir was 3500 cells/mm3 and median platelet nadir was 187,000 cells/mm3. Four patients had white count nadirs from 2000--2500 cells/mm3 and three had nadirs from 500--1500 cells/mm3; also there were four with platelet nadirs less than 100,000/mm3. However, no drug-related infections occurred and no platelet transfusions were required. The major non-hematologic toxicities of the regimen were nausea, vomiting, dizziness, vertigo, and rhinorrhea. These toxicities were limiting and resulted in termination of the trial because of poor patient acceptance and the failure of the combination to exhibit a therapeutic advantage over the similar combination (FAM) that employed weekly 5-fluorouracil in place of Ftorafur.

Adenocarcinoma↗

Phase-II trial of tamoxifen in advanced breat cancer.

Seventy-eight advanced breast cancer patients, most of whom had had prior treatment, were treated with the synthetic antiestogen tamoxifen. The overall objective response rate was 27% (21/78). An additional 19% (15/78) showed disease stabilization. Sixty-seven percent (14/21) of the responses were in soft tissue sites, 24% (5/21) on bony sites and one each occurred in liver and nodular lung disease. Forty percent of patients with soft-tissue disease alone responded, while less than 10% of patients with visceral disease showed responses in visceral sites. The response rate was 28% among patients with a known positive estrogen receptor (ER) assay. It was 21% among patients who had previously received cytotoxic drugs. Toxicity was mild and was seen in nausea and vomiting, hot flushes and vaginal bleeding, and occasional myelosuppression. One patient was withdrawn from the study because of a rash. In two patients the disease flared, once with concomitant hypercalcemia. Tamoxifen is a useful agent for advanced breast cancer even in some patients with visceral disease.

Adenocarcinoma↗

Phase II trial of streptozotocin, mitomycin-C and 5-fluorouracil (SMF) in the treatment of advanced pancreatic cancer.

Ten of 23 patients with advanced measureable adenocarcinoma of the pancreas achieved an objective response after treatment with a regimen consisting of streptozotocin, mitomycin-C and 5-fluorouracil (SMF). The median duration of response is in excess of 7 months and responding patients have lived significantly longer than patients with progressive disease (7.5 + months vs. 3 months). The SMF regimen was adequately tolerated. Principal toxicities included myelosuppression, which was generally mild, nausea and vomiting. There was reversible nephrotoxicity in the form of proteinuria in 30% of patients and persistent axotemia in 9% of patients.

Adult↗

5-Fluorouracil (5-FU), methyl-CCNU, and vincristine in the treatment of advanced colorectal cancer: phase II study utilizing weekly 5-FU.

We report a phase II trial of 5-fluorouracil (5-FU), methyl-CCNU, and vincristine (FMV) combination chemotherapy in advanced colorectal carcinoma. Ten of 25 patients (40%) achieved an objective tumor regression after treatment with FMV chemotherapy. The main toxicities of FMV were hematologic and gastrointestinal. 5-FU was administered in a weekly rather than a loading-dose schedule which allowed for sensitive adjustment of drug dosages according to hematologic toxicity; only 16% of the patients (four of 25) had a wbc count less than 2000 cells/mm3. FMV is significantly more active than 5-FU alone in the treatment of advanced colorectal cancer; however this regimen does not significantly improve survival in responding patients.

Adult↗

Phase I clinical trial of spirogermanium.

Spirogermanium is a new azaspirane antitumor agent, with the metal germanium substituted for a one-carbon moiety in the ring structure. This drug inhibits DNA and RNA synthesis in HeLa cells, is cytotoxic in vitro, and has curative in vivo antitumor activity against the ascitic Walker 256 carcinosarcoma in rats. No hematologic toxicity was recorded during the preclinical toxicologic evaluation. The principal clinical toxic effects observed in this phase I trial were neurologic, manifested as lethargy, dizziness, and ataxia, while a grand mal seizure was produced after an accidental overdose. There was no evidence of hematologic, renal, or hepatic toxicity. A partial response was achieved in a patient with a well-differentiated lymphocytic lymphoma. We recommend that phase II trials be conducted with a twice or thrice weekly dose of 50-80 mg/m2, administered in a 30-minute iv infusion.

Adult↗