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Biomedical subjects

R E Lloyd

Publications and source records attributed to R E Lloyd.

50 records · Page 3Linked to original sources
PubMed1984

Synergism of antiviral activity in cell cultures treated with low concentrations of interferon and interferon-treated lymphocytes.

Human T cells treated with low levels of interferon (IFN) (1-10 units/ml), and washed to remove the IFN, transferred the same level of antiviral activity to recipient WISH cells as an equivalent IFN treatment alone could induce in WISH cells. Further, when T cells pretreated with IFN (1-10 units/ml) were cocultivated with WISH cells in the presence of IFN (1-10 units/ml), a 2.5- to 5-fold greater level of protection developed than could be expected from the additive effect of each. Antibody to leukocyte, fibroblast, or immune IFN blocked the antiviral effect of the respective IFN types but had no effect on the transfer of antiviral activity initiated by leukocyte, fibroblast, or immune IFN. Also, treatment of T cells with actinomycin D blocked the transfer of antiviral activity of IFN-treated T cells. Taken together, the data suggest that the increased antiviral activity is not merely an additive effect of the IFN, but represents a synergistic amplification of protection most likely due to the combination of the separate effects of IFN and IFN-induced transfer. Such interactions would be expected to play a major role in early protection against virus infections in vivo when low levels of interferon are present and lymphocytes are migrating into the area.

Amnion↗
PubMed1983

Cell-to-cell transfer of interferon-induced antiproliferative activity.

Interferon-treated cells rapidly and efficiently transferred the antiproliferative activity of interferon to untreated cells. This phenomenon was not due to the carry-over of interferon by the interferon-treated cells. Thus, to evoke an antiproliferative state, interferon did not directly contact each cell in a population. The results suggest a novel mechanism by which interferon may indirectly regulate cell growth, and suggests that cells other than those of the immune system may play a role in controlling tumor growth in tissue where cell-to-cell contact occurs.

Animals↗
PubMed1983

Microassay for Sindbis virus and interferon activity.

A simple and rapid microplaque assay for Sindbis virus was developed which uses microtiter plates and overlay medium consisting of methylcellulose and specific antibody to Sindbis virus. Discrete plaque formation was consistently observed on baby hamster kidney (BHK-15) cells within 24 h. The assay was reproducible, quantitative, and had about the same sensitivity as the agar overlay technique on chicken embryo cells in 35-mm petri dishes. The microplaque assay could be accurately applied to measuring interferon activity, particularly at low interferon levels. Overall, the microassay methods described here for assay of Sindbis virus yields and interferon activity retain the accuracy of chicken cell macroplaque assays while offering greater simplicity, rapidity, and economy of materials. This assay is also potentially applicable for use with other togaviruses.

Antibodies, Viral↗
PubMed1980

Lipids as a principle for the identification of archaebacteria.

The 'Archaebacteria' consist of several distinct subgroups including methanogens, extreme halophiles and specific thermoacidophiles. These bacteria are distinct from other bacteria with respect to their characteristic RNA compositions, the absence of muramic acid in the cell walls and the predominance of nonsaponifiable [correction of nonsaponifable] lipids. The lipid composition of the archaebacteria consists of isoprenoid and hydroisoprenoid hydrocarbons and isopranyl glycerol ether lipids. The pathways for the biosynthesis of the lipid components are those shared by most microorganisms and demonstrate a close relationship; however, an independent line of descent is indicated by the formation of the isopranyl glycerol ether lipids. This discontinuity formulates a point for delineating the early stages of biological evolution and for dividing bacteria into two subgroups.

Archaea↗
PubMed1979

Comparative trial of low-dose adriamycin plus cyclophosphamide with or without additive hormonal therapy in advanced breast cancer.

We treated 56 women with advanced metastatic breast cancer who had not received prior chemotherapy in a comparative trial of cytotoxic chemotherapy with low-dose adriamycin plus cyclophosphamide alone or in combination with the androgenic steroid calusterone. The response rate to chemohormonal therapy (65%) could not be shown to be statistically better than that for chemotherapy alone (53%) for this size patient population. However, the median remission duration (21.5 months) was significantly prolonged over the 11.5-month remission duration for chemotherapy alone (p = 0.03). The median survival of the chemohormonal therapy group was 23.5 months, whereas that for chemotherapy alone was 13.5 months (p = 0.05). These results indicate that the addition of a potent hormonal agent to effective cytotoxic chemotherapy improves the results of treatment of women with metastatic breast cancer.

Breast Neoplasms↗
PubMed1976

Combination chemotherapy with adriamycin (NSC-123127) and cyclophosphamide (NSC-26271) for solid tumors: a phase II trial.

One hundred and nine adult patients with metastatic carcinoma were treated at 3-4-week intervas with a combination of adriamycin (40 mg/m2 given iv on Day 1) and cyclophosphamide (200 mg/m2/day given orally in divided doses on Days 3-6). Ninety-two of 96 patients who had an adequate trial (minumum of two courses or progression of disease after one course) had follow-up observations of tumor sites and were considered evaluable for response. Overall objective response rates by tumor type were as follows: stage III or IV ovarian adenocarcinoma, 61% (14 of 23 patients); endometrial adenocarcinoma, 67% (four of six patients); cervical adenocarcinoma, 33% (one of three patients); prostatic adenocarcinoma, 18% (two of 11 patients); testicular carcinoma, 33% (one of three patients); lung carcinoma, 21% (four of 19 patients); renal adenocarcinoma, 14% (one of seven patients); gastrointestinal adenocarcinoma, 18% (two of 11 patients); melanoma, 25% (one of four patients); and miscellaneous tumors, no responses in five patients. In patients with ovarian adenocarcinoma who had not previously received any cytotoxic chemotherapy the response rate was 80% (12 of 15 patients) with 33% five of 15 patients achieving complete clinical remission. CRs in these patients have now been maintained for periods ranging from 7 to 12 months. The major toxic effects were mild to moderate leukopenia, alopecia, and nausea with vomiting. Hemorrhagic cystitis was observed in three patients. The combination of adriamycin and cyclophosphamide is an effective treatment for carcinoma of the breast (reported elsewhere), ovary, and endometrium and should be considered for initial chemotherapy in patients with these tumors. Further investigations of its use for melanoma and carcinoma of the lung, prostate, kidney, and gastrointestinal tract are also warranted.

Adult↗