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Biomedical subjects

J A Stratton

Publications and source records attributed to J A Stratton.

At least 19 recordsLinked to original sources

Intraperitoneal cisplatin: comparison of antitumor activity and toxicity as a function of solvent saline concentration.

The use of increasing concentrations of NaCl in the solvent during administration of cisplatin is known to decrease nephrotoxicity, but its effect on antitumor activity is less certain. A murine tumor model employing the subrenal capsule assay was used to test the toxicity and antitumor activity of intraperitoneal cisplatin at different doses of the drug using varying concentrations of NaCl in the vehicle of administration. Toxicity (measured by LD50, weight loss, and nephrotoxicity) was significantly lower in mice treated with cisplatin prepared in 4.5% NaCl as compared to cisplatin prepared in distilled water (DW) or 0.9% NaCl. Administration of 4.5% NaCl subcutaneously along with intraperitoneal cisplatin prepared in DW failed to decrease toxicity. Despite lower toxicity, no decrease in antitumor activity could be demonstrated based on increasing concentrations of NaCl in the solvent during intraperitoneal therapy.

Animals↗

Treatment of advanced and recurrent endometrial carcinoma: correlation of patient response to hormonal and cytotoxic chemotherapy and the response predicted by the subrenal capsule chemosensitivity assay.

The tumors from 38 patients with advanced or recurrent endometrial carcinoma were assayed by the subrenal capsule xenograft assay (SRCA) for sensitivity to hormonal and cytotoxic chemotherapy. Three patients initially received radiation therapy. All other patients received maximal surgical debulking followed by treatment with radiation therapy (5), and/or hormonal (19), and cytotoxic (30) chemotherapy. All the patients who received hormonal chemotherapy had progression of disease. There were 2 complete responses, 5 partial responses, and 26 disease progressions with cytotoxic chemotherapy; and 2 complete responses, 2 partial responses, and 5 disease progressions with radiation therapy. The SRCA was 100% predictive of the response of the tumors to hormonal therapy and had 75% sensitivity, 65% specificity, and 66% efficiency of the response of the tumors to cytotoxic chemotherapy. Laboratory assays of tumor response to radiation therapy were not measured. Those patients with early stage, well-differentiated tumors with no residual disease had the longest survival times. Absence of residual disease after the first surgery was the most important delineator of survival for all categories of patients.

Actuarial Analysis↗

Concordance of combination and single agent chemosensitivity prediction in ovarian carcinoma using the subrenal capsule xenograft assay (SRCA).

The tumors from 62 patients with advanced ovarian adenocarcinoma were assayed by the subrenal capsule xenograft assay (SRCA) for sensitivity to doxorubicin (A), cis-platinum (P), and cyclophosphamide (C), individually and in combination. In some instances only one or two of the individual drugs were assayed; however, the combination, CAP, was always tested. All patients received an optimal surgical debulking (absence of any residual tumor masses greater than or equal to 2 cm) followed by chemotherapy with CAP. Forty-two tumors were predicted to be sensitive to CAP by the SRCA; 51 of 71 (72%) individually tested drugs agreed with this determination. Twenty-one tumors were predicted to be resistant to CAP and 32 of 36 (89%) individually tested drugs agreed with this determination. In this preliminary study, 11 patients had surgically documented partial responses to CAP chemotherapy. All of these patients had tumors which prospectively tested as sensitive to CAP in the SRCA: 13 of 18 (72%) of separately tested drugs were in concordance with this sensitivity. Fourteen patients failed CAP therapy and three of these failures were predicted prospectively by the SRCA: 9 of 9 (100%) of separately tested drugs were in concordance. Thus, there is an overall concordance of 82% (22/27) between the individual components of a combination chemotherapy and the combination therapy itself. It would seem that extrapolations of sensitivity or resistance can be made from the individual components.

Adenocarcinoma↗

Use of a murine model for comparison of intravenous and intraperitoneal cisplatin in the treatment of microscopic ovarian cancer.

The most effective method for the delivery of cisplatin chemotherapy in the treatment of epithelial ovarian cancer limited to the presence of microscopic intraperitoneal disease is a controversial issue. The use of intravenous (iv) versus intraperitoneal (ip) cisplatin was evaluated in a murine tumor model of human epithelial ovarian cancer. Using single dose cisplatin therapy for microscopic disease limited to positive cytology of abdominal disease and microscopic peritoneal involvement, ip therapy had significantly greater (P less than 0.001) survival time than iv therapy (28 +/- 1.6 days vs. 23 +/- 1.6 days, respectively). Once ascites and macroscopically evident intraperitoneal tumor became apparent, no difference could be found in survival time based on iv versus ip therapy (16 +/- 3 days for both groups); though both forms of therapy significantly (P less than 0.05) prolonged survival in mice with macroscopic disease when compared to control animals (13 +/- 1.2 days). The evidence presented implies that ip cisplatin therapy is significantly more effective than iv therapy when dealing with microscopic intraperitoneal disease.

Animals↗

Relationship of serum CA125 and lipid-associated sialic acid tumor-associated antigen levels to the disease status of patients with gynecologic malignancies.

Serum samples obtained from 133 patients with gynecologic malignancies were assayed for two tumor-associated antigen markers: CA125, an ovarian marker, and lipid-associated sialic acid, a nonspecific marker. In the patient population, there were 77 papillary serous and 19 unspecified ovarian adenocarcinomas, and 24 miscellaneous ovarian carcinomas. Thirteen patients had nonovarian malignancies. Sixty-nine percent (74 of 108) of the patients with known disease had abnormal CA125 levels, whereas only 32% (20 of 63) had abnormal lipid-associated sialic acid levels. Changes in CA125 serum levels reflected the disease status of the patients for whom there were serial serum samples. Normal levels of CA125 corresponded to no evidence of disease in 100% (six of six) surgically evaluated patients and 75% (30 of 40) of clinically evaluated patients. Changes in CA125 levels from normal to abnormal corresponded to disease progression in 80% (12 of 15) of the patients. Decreases in CA125 levels from abnormal to normal corresponded to complete clinical response in 55% (11 of 20), and partial clinical response in 45% (nine of 20). No such correlations were available for lipid-associated sialic acid antigen levels. For tumors that express CA125 antigen, serum levels appear to be a good marker for the extent of malignant gynecologic disease. Levels of CA125 that rose from normal to abnormal were usually associated with recurrent disease.

Adenocarcinoma↗

Treatment of a syngeneic rat tumor with magnetically responsive albumin microspheres labeled with doxorubicin or protein A.

The tumoricidal activity of magnetically responsive albumin microspheres tagged with either doxorubicin or Staphylococcal protein A was tested against an induced mammary adenocarcinoma, 13762, implanted subcutaneously in the tail of female Fischer-344 rats. Magnetically responsive albumin microspheres containing Fe3O4 particles were prepared by an emulsion polymerization method incorporating either doxorubicin or protein A into the albumin matrix. Microspheres were produced with an average diameter of 1 micron (0.2 to 1.5 micron) in a concentration of 10(9) microspheres/mg. Microspheres were injected either directly into the tail artery and localized to the implanted tumor using a permanent bipolar adjustable gap magnet with a field strength of 8000 Oe, or directly into the femoral vein with no magnetic localization. Control groups consisted of animals treated with intravenously or intraarterially administered microspheres containing no active agent, and a no-treatment group. Survival was significantly greater in both the doxorubicin- and protein A-treated animals than in the control groups. First appearance of local metastases was prolonged in only the intraarterial magnetically localized doxorubicin-treated group of animals. Tumor growth rate was significantly depressed in both intraarterially magnetically localized treatment groups when compared to intravenously administered nonlocalized treatment groups. Magnetically responsive albumin microspheres appear to be an effective delivery system for cytotoxic agents and biologic response modifiers. Significant tumoricidal activity can be produced with a one-time administration of these agents utilizing this drug delivery system.

Adenocarcinoma↗

Quantitative nuclear DNA analysis of human ovarian adenocarcinoma: compared before and after chemotherapy and correlated with clinical response.

Quantitative DNA measurements on 18 human ovarian adenocarcinomas were made by computerized image analysis. The DNA content of the tumor cells was measured on specimens of tumor obtained at the initial diagnostic surgery and at second-look surgery after treatment with chemotherapy. The mean DNA content of the specimens and the ploidy pattern of the tumor cells were determined. With the exception that borderline tumors had near normal ploidy patterns and mean DNA content, there was no consistent correlation between the stage of disease, grade, or histiologic character of the tumor and either the DNA content or ploidy pattern. But it was noteworthy that all three of the patients who had complete responses (negative second-looks), also had tumors with DNA content and ploidy patterns near triploid. When the ratio of mean DNA content before and after chemotherapy was determined for each ploidy group, there was an apparent correlation between this ratio and clinical status of the patient 10 month after chemotherapy. That is, patients with low ploidy tumors and high DNA content ratio (greater than 1.25) had a better prognosis than patients with high ploidy tumors and lower DNA content ratios (less than 1.25). Thus, although the mean DNA content of the tumor at the initial surgery was not in itself of sufficient prognostic value, when the mean DNA content of the tumor after chemotherapy is also known, an accurate picture of the patients clinical response could be determined.

Adenocarcinoma↗

Accurate laboratory predictions of the clinical response of patients with advanced ovarian cancer to treatment with cyclophosphamide, doxorubicin, and cisplatin.

Seventy-six patients with advanced ovarian cancer treated with cyclophosphamide, doxorubicin, and cisplatin (CAP) at 3-week intervals were tested for the response of their tumors to treatment with CAP in the subrenal capsule tumor implant assay. Thirty-four of the patients' tumors were assayed prospectively before clinical treatment and 33 were assayed retrospectively, after clinical treatment with CAP. Nine of the patients' tumors were assayed both prospectively and retrospectively. All of the patients underwent a tumor debulking laparotomy. Of the patients with clinically measurable residual disease, 17 had a partial response of at least 50% regression of disease, and 11 had a progression of disease. Of the patients with known residual but nonmeasureable disease, 7 had surgically verified complete responses, 8 at least 50% regression, and 23 had progression of disease: 10 had no evidence of disease clinically but had not had surgical confirmation. Twenty-six of the tumors were adenocarcinomas not otherwise specified (2 grade I, 2 grade II, and 22 grade III), 39 were serous adenocarcinomas (7 grade I, 9 grade II, and 23 grade III), 7 were endometrioid adenocarcinoma (all grade III), 3 were mucinous adenocarcinomas (1 each of grade I, II, and III) and 1 was an adenosquamous carcinoma (grade III). Thirty-four of the patients failed the therapy. The subrenal capsule (SRC) assay predicted 21 of these failures (4 prospective and 17 retrospective). Thirty-two of the patients responded to CAP chemotherapy. The SRC assay accurately predicted the clinical regression of the tumors of 22 of the patients (15 prospective and 7 retrospective). Second-look laparotomy confirmed 7 patients with no evidence of disease, 5 patients with minimal disease, and 5 patients with a greater than 50% reduction of their disease. The SRC assay predicted the response of all these patients except 2 with partial responses to chemotherapy. Thus, while the overall positive predictive value of the SRC assay in this study is 65%, it is 100% for those patients whose tumors respond completely and for those who have minimal residual disease after CAP chemotherapy.

Animals↗

Effect of oral contraceptives on leukocyte phagocytic activity and plasma levels of prostaglandin E2 and thromboxane B2 in normal menstruating women.

Mononuclear and polymorphonuclear cells were isolated from the peripheral blood of normal menstruating women. Four of the subjects were not using oral contraceptives and five were taking various formulations. The women were tested once a week for 12 consecutive weeks. Plasma levels of 6-keto-prostaglandin F2 alpha (6-KF), prostaglandin E2 (PGE2), thromboxane B2 (TxB2), estrogen, and progesterone were measured by specific radioimmunoassays. The phagocytic activity of the mononuclear and polymorphonuclear cells isolated from the peripheral blood was measured with a bacterial phagocytosis and killing assay. The phagocytic activity of both types of cells was depressed perimenstrually in both groups of women. However, examination of individuals showed that those subjects not taking oral contraceptives had a worsening of phagocytic activities with approaching menses while the oral contraceptive subjects generally had an improving of these activities at this time. We were unable to correlate the phagocytic activities with either hormone or prostaglandin levels in the plasma of these subjects. However, the subjects on oral contraceptives had significantly lower levels of PGE2 and TxB2 than those women who were not using oral contraceptives.

Contraceptives, Oral↗

Action of 2-beta-D-ribofuranosylthiazole-4-carboxamide (tiazofurin) against untreated human ovarian cancers in the murine xenograft assay.

The activity of 2-beta-D-ribofuranosylthiazole-4-carboxamide (tiazofurin) was determined in nine untreated human ovarian cancer specimens, using the murine subrenal capsule xenograft assay. Tumor cytotoxic effect was demonstrated in seven out of the nine tumors implanted. The drug was well tolerated by the test animals. Tiazofurin may prove to be an effective chemotherapeutic agent in the treatment of ovarian cancer.

Animals↗

Effect of maternal parasitic disease on the neonate.

Parasitic disease is the most common infectious disease complication of pregnancy worldwide, resulting in maternal debilitation and fetal prematurity and low birth weight. The increasing incidence of these diseases in our population led to the present study of 125 patients, 34 of whom were found to be infected with at least one intestinal parasite. In contrast to studies in developing countries, no significant differences in either maternal anemia, or fetal birth weight, or prematurity were found between the infected and non-infected groups. However, there was a three-fold increase in the incidence of significant neonatal hyperbilirubinemia in the parasitized group. Parasitic disease complicating pregnancy in our population does not appear to exert the same adverse effect on mother and fetus as that described in other countries. In view of the limited pathology associated with parasitic disease, treatment, other than with iron and vitamin supplementation, is not routinely indicated in pregnancy in populations similar to ours. However, due to the increased incidence of neonatal jaundice and morbidity we would recommend close observation of the neonates in the immediate postpartum period.

Adult↗

In vivo alteration of RES phagocytosis by magnetic albumin microspheres.

The effect of non-localized magnetically responsive albumin microspheres (MR-AMS) on RES phagocytic function was investigated. MR-AMS and MR-AMS containing Adriamycin (MR-AMS-ADR) were injected intravenously in rats at a dose which saturated all RES phagocytes. The ability of the RES to clear the bloodstream of a subsequent suspension of MR-AMS or streptococci was then analyzed over a three day period. MR-AMS clearance was enhanced after initial RES saturation with MR-AMS but depressed when the saturating agent was MR-AMS-ADR. Bloodstream clearance of streptococci was depressed by MR-AMS and MR-AMS-ADR. Localization of MR-AMS in the RES might depress RES phagocytosis by physical saturation of phagocytes or by a direct toxic effect of encapsulated chemotherapeutic agents.

Animals↗

Response of human adenocarcinoma to chemotherapy: as sole agents and in combination with sodium ibuprofen.

The sensitivity of 12 human tumors to various chemotherapeutic agents was measured in the 6-day subrenal capsule xenograft assay. All of the tumors were adenocarcinomas: 9 ovarian, 2 colon, and one endometrial. Doxorubicin, cisplatin, melphalan, 5- fluorouracil , methotrexate, and vinblastine sulfate were tested for antineoplastic activity on all tumors. In addition, a prostaglandin synthetase inhibitor, sodium ibuprofen, was assayed for cytostatic activity and for the ability to enhance the cytotoxic activity of melphalan and vinblastine sulfate. The response of the tumors to the cytotoxic agents were variable, but 5 of the 12 tumors showed a significant reduction of growth when the animals were treated with sodium ibuprofen alone. The addition of ibuprofen to the chemotherapeutic agents did not significantly alter the therapeutic activity of melphalan, but decreased the effectiveness of vinblastine in one case. When ibuprofen was given in combination with a cytotoxic drug, the primary cytoreductive effect was that of the cytotoxic agent.

Adenocarcinoma↗

Chemosensitivity testing of nonsolid tumors by the subrenal-capsule implant assay.

A procedure to test chemosensitivity of nonsolid tumors using the subrenal-capsule xenograft assay has been developed. This technique is applicable to the study of malignant effusions and hematopoietic tumors. The tumor cells are centrifuged to form a pellet and the pellet is resuspended in the presence of bovine fibrinogen to form a jelled clot. This clot is cut into fragments which are implanted beneath the renal capsule of normal mice. The growth of the tumor cells from ovarian adenocarcinoma obtained from ascitic fluid is better than that of tumor fragments from the solid tumors. This is probably a reflection of the greater viability of tumor cells from ascitic fluids. The sensitivity to chemotherapy was the same for the solid tumor and its malignant effusions.

Adenocarcinoma↗

The subrenal capsule tumor implant assay as a predictor of clinical response to chemotherapy: 3 years of experience.

The clinical response to chemotherapy of a series of female patients with advanced pelvic malignancies was compared to the response of their tumors to the same agents in the murine subrenal capsule implant assay. A total of 194 different patients were studied in 242 different assays; 89.3% of the assays were evaluable. There were 83 prospective assays (assays performed before the patient received the chemotherapy) of 66 different patients for which clinical correlations were available. In these assays the sensitivity (frequency of positive test results in responding patients) was 85.0%, the specificity (frequency of negative test results in nonresponding patients) was 57.1%, and the efficiency (percentage correctly classified) was 63.9%. There were 100 retrospective assays (assays performed after the patient had been treated with the chemotherapy) of 69 different patients for which clinical correlations were available. In these assays the sensitivity was 66.7%, the specificity 70.7%, and the efficiency 70.0%. Thirty-one of the patients had both prospective and retrospective assays. There were 59 patients for whom the clinical response to chemotherapy could not be determined. It is believed that the clinical utility of the SRC assay has been validated by the good prospective sensitivity of the assay.

Animals↗

A murine model of squamous intraepithelial neoplasia.

Focal areas of intraepithelial neoplasia were induced in the skin of mice by 1 intraperitoneal injection of urethane followed by twice weekly topical applications of 12-0-tetra-decanoyl phorbol-13-acetate (TPA). Microscopic lesions with histologic characteristics of intraepithelial neoplasia were seen in all animals after 11 weeks of TPA application. Fluorescence microscopy verified the increased DNA content of these lesions. This easily produced animal model of premalignant disease might be valuable in the preclinical testing of topically applied antineoplastic agents.

Administration, Topical↗

Depressed mononuclear cell phagocytic activity associated with menstruation.

The peak of the normal distribution curve for pelvic inflammatory disease occurs near the onset of menses. This study was undertaken to determine if there were changes in the cell-mediated immunity of normal menstruating women which could explain the increase in inflammatory disease. The cellular immune response of 8 normal women, measured by number of T- and B-cells and response of mononuclear cells to stimulation with mitogen, was not dependent on the menstrual cycle. However, there was a significant decrease in phagocytic activity of mononuclear cells early in the cycle. The depressed phagocytic activity was not altered by treating the subjects with ibuprofen.

Female↗

Depressed natural killer cell activity in tumor-bearing rats: effect of immunotherapy and cytoreductive chemotherapy.

A single-cell cytotoxicity assay was used to determine the number of effector cells in the peripheral blood of normal and tumor-bearing Fischer 344 female rats which bound to and lysed K562 target cells. Of the blood leukocytes of normal rats 18.4 +/- 2.6% bound to K562 target cells; one-third of the conjugated target cells were killed as evidenced by trypan blue uptake. Cells isolated from the blood of rats bearing mammary adenocarcinoma R3230 or 13762 bound fewer target cells, 6.3 +/- 1.1 and 7.1 +/- 1.8%, respectively. The proportion of dead conjugated target cells was not different from that of normal rat leukocytes if the leukocytes were from rats bearing 13762 but was reduced by one-half if the leukocytes came from rats bearing R3230. Treatment of the tumor-bearing rats with cytoreductive chemotherapy returned the percentage conjugation to target cells to normal levels if the tumor growth was inhibited more than 70%. Treatment of the tumor-bearing rats with immunomodulating agents did not inhibit the growth of the tumors, but treatment with sodium ibuprofen or muramyl dipeptide increased the percentage conjugation significantly.

Acetylmuramyl-Alanyl-Isoglutamine↗