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C Delfini

Publications and source records attributed to C Delfini.

At least 73 records · Page 4Linked to original sources
PubMed1980

[The brain of Gallus domesticus L., a quantitative analysis of embryonic and postnatal growth].

The study among domestic fowls (Gallus domesticus L.) of the growth allometry of various brain structures in comparison with the body weight during the embryonic and post natal period leads to two different conclusions: Every structure shows a growth alteration which occurs about hatching time and is characterized by an abrupt decrease of the slope of the reducted major axis. The comparison of the allometric characteristics of every structure with those of the entire brain allows to distinguish between three kinds of growth; regressive, steady or progressive. A slow and early growth is typical of a phylogenetically ancient structure; a dynamic and late growth shows a phylogenetically recent structure. This corroborates the corticoid trend among some striated complexes (Neostriatum, ventral Hyperstriatum) that several authors had thought of.

Animals↗
PubMed1979

Resistance of African green monkey kidney cell lines to actinomycin D: drug uptake in 37 RC cells after persistent inhibition of transcription.

37 RC cells, a cultured line derived from African green monkey kidneys, survived long treatments with actinomycin D (AMD; 0.1 to 0.5 mug/ml) under strong inhibition of ribonucleic acid synthesis and blocking of cell division. One aspect of the complex cellular response to this treatment was a progressive lowering of the influx rate of AMD and, consequently, of its endocellular concentration, leading to a late resurgence of transcription. Overall protein synthesis decreased in AMD-treated cells, but more of the residual protein was exported to the cell surface, a fact associated with the development of numerous strands of endoplasmic reticulum and Golgi bodies in the cytoplasm. The lowering of AMD influx during the treatment was not simply due to the decay of protein synthesis, and there was no evidence for a carrier-mediated transport of the drug. It was paralleled by, but seemingly not related to, modifications in cellular microtubules and microfilaments. The rate of AMD influx was restored to levels comparable to those of untreated cells by short exposure to ethylenediaminetetraacetic acid and trypsin. It is concluded that the changes in plasma membrane of 37 RC cells, creating an obstacle to the influx of AMD after long treatment with this drug, probably consist of an accumulation and/or a different distribution of glycoproteins or other surface components on the cell surface.

Animals↗
PubMed1975

Study on the reinitiation of transcription in 37 RC cells after actinomycin D inhibition. Spectrum of major RNA species resynthesized after maximal suppression by the drug.

The reinitiation of the synthesis of major RNA species has been studied in 37 RC cells after maximal inhibition of RNA synthesis by actinomycin D (AMD). During the period of recovery from AMD, resynthesized RNA (rec-RNA) is initially composed of almost exclusively light (4-14S) heterogeneous RNA species. All normal species of RNA can be detected in the rec-RNA spectrum as early as 3 h after AMD removal. The synthesis of low molecular weight methylated RNA species increases slightly during the early period after AMD removal, while the increase of low molecular weight unmethylated species is more significant during the same period. Much of the radioactivity in the polyribosomal fraction is EDTA and puromycin sensitive. Since polysomal, puromycin-sensitive RNA is polyadenylated (as evidenced by the binding of poly-U filters), and is heterogenous in size, it belongs to the m-RNA class. The synthesis of m-RNA increases immediately after AMD removal, whereas the reinitiation of the r-RNA synthesis occurs after a lag period of about 2 h. The kinetics of recovery of the synthesis of major RNA species from AMD inhibition show a size dependency comparable to the size-related sensitivity to AMD inhibition in other cellular systems. This dependency is most clearly seen in HnRNA, the AMD sensitivity of which is measured by the length of the lag period between AMD removal and the appearance of HnRNA fractions in a sucrose density gradient. Low molecular weight HnRNA reappears first, whereas heavier fractions of HnRNA appear in the spectrum after a lag period, the length of which is in direct relation to the position of the HnRNA fraction in the gradient.

Cell Line↗
PubMedDate not supplied

An attempt to obtain a specific antiserum for in vitro immunological conditioning of bone marrow in acute non-lymphoblastic leukemia.

An antiserum was produced in rabbits to acute undifferentiated leukemia (AUL) antigens. Partial absorption of the antiserum allowed the removal of the cytotoxic activity against normal mononuclear cells of peripheral blood and bone marrow, in contrast to blast cells from acute and chronic leukemias, which were killed by the antiserum in a standard NIH cytotoxicity test. These observations suggest that antigens present on blast cells of AUL are also expressed on some acute and chronic leukemic cells and that these antigens could be interpreted as B or leukemia-associated antigens because of the disappearance of all cytotoxic activity of the immune serum after extensive absorption with B cells from chronic lymphoid leukemia.

Acute Disease↗
PubMedDate not supplied

Cryopreservation of human lymphoid cells from various tissues.

Normal and pathological lymphoid cells, collected from different sources, were cryopreserved using a programmed freezing procedure. With this cryopreservation technique, the percentage of T and B cell surface markers and the proliferative response to mitogens were not influenced by 21 and 35 days of storage in liquid nitrogen. The recovery percentage of the lymphoid cells was satisfactory when fetal calf serum was added, as a protein source, to the medium during freezing and thawing phases, while a very low percentage of cells was recovered if the fetal calf serum was omitted.

Antigens, Surface↗
PubMedDate not supplied

Effectiveness of fludarabine in advanced B-cell chronic lymphocytic leukemia.

AIMS: The study was carried out to investigate the efficacy and toxicity of fludarabine phosphate in the treatment of B-cell chronic lymphocytic leukemia (B-CLL) in previously treated patients. METHODS: Sixteen patients, 11 males and 5 females, 9 in stage B and 7 in stage C, according to the Binet Staging System, were treated with a maximum of 6 cycles of fludarabine (25 mg/m2) for 5 days, every 4 weeks. All patients had been pretreated, 10 were refractory to standard regimens, 5 were in relapse, and 1 patient was in partial remission. RESULTS: Thirteen patients were judged suitable for evaluation. Overall 9 patients were responsive to treatment; 4 complete and 5 partial responses were observed. Of the 4 patients in complete remission, 3 were alive at 6, 10 and 13 months, respectively, from the beginning of treatment. One patient died after 11 months for acute graft-versus-host disease after allogenic bone marrow transplantation by an HLA sibling donor. Two of the 5 patients in partial remission were alive at 7 and 17 months, respectively, and the other 3 died (2 of disease reexpansion after 14 and 16 months and 1 of septic shock following pneumonia). Four patients were not responsive to treatment: 1 died from disease progression after 8 months from the beginning of therapy, 1 from cardiac failure after 9 months, 1 from septic shock following meningitis, and 1 was alive after 7 months of follow-up. Treatment was well tolerated, with nausea and vomiting in only one patient. We observed two episodes of pneumonitis, without any evidence of the responsible agent, a tumor lysis syndrome with acute renal failure, a recurrence of autoimmune thrombocytopenia, and a Coombs-positive hemolytic anemia. CONCLUSIONS: Fludarabine phosphate is effective in the treatment of patients with advanced B-CLL, even in those refractory to multiple chemotherapy regimens.

Aged↗