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C Greco

Publications and source records attributed to C Greco.

At least 91 records · Page 5Linked to original sources
PubMed1983

Influence of scheduling on therapeutic and toxic effect of AMSA in Lewis lung carcinoma.

The antitumor activity and toxic effect of AMSA were studied in Lewis lung carcinoma (3LL) at various stages of growth. The total dose of drug injected IP was 15 mg/kg, which is equivalent to the LD10. Different administration schedules were tested, these being single-injection schedules (day 1, 7, or 10 after tumor implantation) and repeated low-dose-injection regimens (days 1, 4, and 7 and days 1-7 after tumor implantation). Tumor weight inhibition, retardation of growth, reduction in the number of metastases, and median survival time of treated mice over controls were analyzed as end-points to evaluate the antitumor activity of AMSA. Early deaths and changes in white blood cell count were considered as parameters of toxicity. Our findings can be summarized as follows: (1) AMSA is only minimally effective against primary 3LL tumor at all the growth stages examined and no schedule-dependency is detected; (2) a greater reduction in metastases (70%-77%) is found when the drug is administered fractionally than when it is given in a single dose (39%-60%); (3) irreversible leukopenia is induced by the single-dose schedule of AMSA administration while after repeated low doses the white blood cell counts are in the same range of those of the control groups. Therefore, because of the schedule-dependency of toxicity and reduction in metastases, fractionated administration of AMSA at this dose level would be suitable for adjuvant chemotherapy.

Aminoacridines↗
PubMed1983

Signaled tailshock is perceived as similar to a stronger unsignaled tailshock: implications for a functional analysis of classical conditioning.

Water-deprived rats given fixed-electrode, variable-intensity tailshock at random times rated each trial by pressing either a "high-aversiveness" or "low-aversiveness" lever in order to obtain water. Trials on which a warning signal preceded tailshock resulted in more "high-aversiveness" leverpressing than did otherwise equivalent unsignaled trials. The magnitude of this effect increased and decreased as a function of several parameters including signal-shock interval, signal duration, and range and absolute value of shock intensities but was never reversed despite efforts to achieve such a reversal. Variation in the size of the effect as a function of signal parameters as well as lick suppression scores indicated that the signal had acquired aversive characteristics, which suggests that the effect of the signal on lever choice was due largely to the aversiveness of the signal summating with the aversiveness of the tailshock. Several hypotheses concerning factors that might have either masked or prevented classically conditioned preparatory responses elicited by the signal from reducing tailshock aversiveness were tested and rejected. Despite the greater aversiveness of the signaled condition, when given the choice of receiving or not receiving the signal, the animals displayed a preference for signaled tailshock. Implications for the role of preparatory responding both in the preference-for-signaled-shock phenomenon and in classical conditioning are discussed.

Animals↗
PubMed1982

DNA content distribution of in vivo and in vitro lines of Lewis lung carcinoma.

The kinetic features of Lewis lung carcinoma (3LL) and of two in vitro and two in vivo derivative lines were studied by flow cytometry. The in vitro lines C108 and BC215 show the same tetraploid DNA content and a very similar cell cycle structure, characterized by a prevalent S fraction. Also, the in vivo lines, the original 3LL and M1087, show a tetraploid DNA content, while the BM21548 is characterized by a hyperdiploid DNA mode and a broader distribution of DNA values. No difference in the modal DNA value is found between each primary tumor and the corresponding lung metastases for all the in vivo lines. In addition, an increase in the G1 component corresponding to a decrease in the S fraction is observed during the tumor growth. These kinetic features were related to some malignant properties of 3LL lines, such as growth pattern and metastatic potential. Our findings indicate that a direct correlation is not always possible to establish.

Animals↗
PubMed1982

Extracellular paraprotein globules in a patient with monoclonal gammopathy.

A patient with a plasma cell disorder and IgA lambda paraprotein had the unusual finding of numerous, large, opaque, extracellular globules in her bone marrow and liver. While plasma cell intracellular inclusions are well documented, identification of such material in extracellular sites is not. These globules were of various sizes, stained light to dark blue with Wright's stain, were gray in hematoxylin-eosin preparations, and were fluorescent when stained with conjugated antibodies to lambda, but not to kappa, light chains. They strongly resembled the inclusions (Russell bodies) seen in plasma cells and are believed to be massive accumulations of immunoglobulin. The clinical significance of this morphological finding is unknown, but physicians interpreting bone marrow specimens should be aware of this unusual feature.

Aged↗
PubMed1981

Different metastatic potential of in vitro and in vivo lines selected from Lewis lung carcinoma: correlation with response to different bleomycin schedulings.

In vitro and in vivo variant cell lines selected from Lewis lung carcinoma are described. In vitro tumor lines are shown to differ in their metastatic potential, evaluated as lung colony-forming ability. Moreover, corresponding in vivo sublines, derived from intramuscular implant of cultured tumor cells, exhibit the same behavior for metastases formation as their in vitro counterpart. The metastatic potential of the in vivo lines has been evaluated both as lung colony-forming ability and as spontaneous metastasis formation. Response to bleomycin (BLM) treatment has been studied on the in vitro and the in vivo lines. Results reported show that the most metastatic lines, in vitro and in vivo, appear to be more resistant to a BLM treatment and that appropriate fractionation regimens can improve both the percentage of cell kill and the percentage of metastases reduction.

Animals↗
PubMed1980

Cell proliferation kinetics of the intramuscularly implanted Lewis lung carcinoma.

The growth kinetics of the Lewis lung carcinoma tumor was studied. The main proliferative parameters of an early stage of the growth (8th day after tumor implantation) were derived from the analysis of the growth curve and the fraction of labeled mitoses (FLM curve). The occurrence of proliferative changes due to the transplantation was confirmed. The main variations observed concern a shortening of the cell cycle time, a prolongation of the S phase duration and an increase in cell loss. A critical analysis of the results of this preliminary study is reported.

Animals↗
PubMed1980

Chemotherapeutic activity and histopathologic feature of BCNU + 5-FU effect on Lewis lung carcinoma.

In this study we investigated the effects of BCNU + 5-FU on the intramuscularly implanted Lewis lung carcinoma and on its spontaneous lung metastases. Chemotherapeutic agents were given i. v. either alone and in combination seven days after transplantation of 2.5 x 10(5) viable tumor cells, when the average weight of the primary tumor was 500 mg. The analysis of the following parameters: T/C, T--C, of %-metastases reduction, indicates that the simultaneous administration of BCNU + + 5-FU induces a more relevant response on the Lewis lung carcinoma than single drug therapy, especially evident at level of lung metastases.

Animals↗
PubMed1979

Cyclophosphamide and iphosphamide against Lewis lung carcinoma: evaluation of toxic and therapeutic effects.

In the present report, investigations have been carried out to evaluate toxic and therapeutic effects of cyclophosphamide vs its isomer iphosphamide. Cytostatic action of the 2 drugs was assayed on the murine Lewis lung carcinoma (3LL). It has been observed that iphosphamide is less toxic as compared to cyclophosphamide (LD50 IP LD50 CP = 1.5); on the other hand, to reach the same therapeutic effectiveness on 3LL, an iphosphamide dose 1.6 - 2 times higher than that of its parent compound is necessary.

Animals↗