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C M Montecucco

Publications and source records attributed to C M Montecucco.

34 records · Page 2Linked to original sources
PubMed1986

Proliferative characteristics and ploidy of human brain tumors by DNA flow cytometry.

We studied nuclear DNA distribution by flow cytometry in 59 human brain tumors. Samples were frozen at -20 degrees C immediately after surgery and unicellular suspensions were obtained with a mechanical dissociation technique. Nuclear DNA was stained with propidium iodide. Normal human brain tissue was used as a diploid reference standard. In 86.3% of benign tumors an unimodal DNA distribution with a DNA index usually within the diploid range was found. Among malignant tumors, 64% had un unimodal DNA distribution with diploid or near-diploid modal DNA content. The remaining 36% showed an additional cell peak with a DNA index ranging from 1.15 to 1.92. The percentage of S-phase cells was higher in malignant (median = 3.8) than in benign tumors (median = 1.9) (p less than .001), without correlation to histological tumor subtype.

Aneuploidy↗
PubMed1985

Peptichemio, vincristine, prednisone induction treatment in multiple myeloma.

Twenty-nine patients with multiple myeloma, 16 untreated and 13 relapsing after treatment with melphalan and/or cyclophosphamide, were treated with Peptichemio (PTC), vincristine (VCR) and prednisone (PRD). The treatment was well tolerated and produced rapid resolution of bone pain and improved performance status in symptomatic patients. Rapid and marked monoclonal component reduction (greater than 50 per cent) was noted in 50% of previously untreated and 31% of previously treated patients. The median survival of previously untreated patients was 27 months, 19 months for stage III patients. Four patients resistant to common alkylating agents responded to PTC-VCR-PRD treatment and achieved long remissions (from 18 to 38 months). The therapeutic results suggest that the present combination regimen may be indicated for induction treatment of multiple myeloma patients in an advanced stage of the disease, and for treatment of myeloma patients refractory or resistant to melphalan and/or cyclophosphamide.

Adult↗
PubMed1985

Propidium iodide staining of cytoautoradiographic preparations for the simultaneous determination of DNA content and grain count.

A new method is described for staining cell nuclei with propidium iodide in preparations that have been processed for autoradiography. The permeability of the stripping film to the dye molecule has been studied, as have the staining conditions, in order to optimize the stoichiometry of the DNA-dye interaction. A procedure has also been set up to allow the simultaneous measurement of DNA content and grain count on the same cell.

Anemia, Hemolytic↗
PubMed1981

Effect of vincristine on bone marrow cells of patients with multiple myeloma. A cytokinetic study.

The cytokinetic changes induced by Vincristine (VCR) on bone marrow erythroblasts, myeloid cells and neoplastic plasma cells have been studied in four patients with plasma cell malignancies using combined DNA cytofluorometry and in vitro tritiated thymidine cytoautoradiography. The changes observed 9 h after the administration of the drug were in accordance with its S-phase specificity. The magnitude of the stathmokinetic effect was in fact roughly proportional to the proliferative activity of the different cell lines, i.e., marked on the erythroblasts, less evident on the myeloid cells and still lower on the plasma cells. In this last cell population VCR has also blocked or partially impaired the DNA synthesis. Nine days after VCR, the plasma cells were recruited into the proliferative cycle while the regeneration of the hemopoietic cells was already exhausted. Repeated administrations of VCR spaced at about 9 day intervals are more and more effective on the plasma cell population, since the S place specificity of the drug against the recruited plasma cells is potentiated. On the contrary, the regeneration of the hemopoietic cells is protected by this time interval.

Autoradiography↗
PubMed1980

A rapid cytofluorometric method for quantitative DNA determination on fixed smears.

A study has been made of the possibility of using propidium iodide (PI) for the cytofluorometric determination of DNA in fixed smears. A preliminary spectrofluorometric study made it possible to define the optimal conditions for the excitation wavelength and the intensity of the emitted fluorescence. The stoichiometry and specificity of the DNA-PI bond were studied in different materials and for different fixation procedures. In order to check whether RNA might interfere, it was extracted enzymatically from test preparations selectively. The data from such treated sections were not significantly different from those obtained by means of the fluorescent Feulgen reaction (Pararosaniline-SO2) on the same material. On the other hand, some of the advantages of the PI method are important: (a) the time required for making ready and staining the preparations is very short, and in any case is considerably shorter than the Feulgen method; (b) the high quantum yield of the DNA-PI complex induces very high fluorescence intensities, which can, therefore, be easily measured, even with low sensitivity instruments; (c) the spectral conditions are particularly favourable for excluding the inner filter effect from the measurement; (d) the photo-decomposition is considerably lower compared to that found in preparations stained by the conventional Feulgen method. The wide possibility of excitation (from the u.v. to the green), together with the limited extent of the emission band (which is mainly in the red) are also conditions that are particularly favourable for obtaining multi-parametric determinations simultaneously from the same cell.

DNA↗
PubMed1980

Cytokinetic changes in the peripheral blood of leukemic patients during cytostatic therapy. V. Effect of VP 16 213 studied with flow cytofluorometry and cytoautoradiography.

The cytokinetic effects induced by VP 16 213 (50-60 mg/sqm/12 hrs for 10 doses) on the peripheral blood and bone marrow blasts of two patients with acute myelomonocytic leukemia have been studied using DNA flow cytofluorometry and in vitro tritiated thymidine cytoautoradiography. Besides a striking cytocidal effect, the drug induced cell synchronization in the G2 phase of the cell cycle as evidenced by the building up of tetraploid nuclei without an increase in mitotic figures. The synchronizing effect was greater in the bone marrow than in peripheral blood. In one patient, the removal of the G2 block was observed which paralleled an increase in proliferative activity. The usefulness of flow cytofluorometry for rapidly detecting the cytokinetic changes induced in acute leukemia blasts by cytostatic drugs is affirmed.

Autoradiography↗
PubMed1980

Cytokinetic changes in the peripheral blood of leukemic patients during cytostatic therapy. VI. Effect of arabinosylcytosine.

Flow and conventional DNA-cytofluorometry and in vitro tritiated thymidine cytoautoradiography were employed in the study of the cytokinetic changes induced by Ara-c on the peripheral blood blast cells of six patients with acute non-lymphoblastic leukemias. Nine courses of therapy were studied, in 5 of which Ara-c was administered in low pulse doses (20-60 mg/sqm) repeated every 12 hrs and in the other 4 it was administered in continuous infusion (90-150 mg/sqm) lasting 24 hrs. Low repeated pulse doses have little cytocidal effect and increase the 2n-4n cell percentage and, less markedly, the LI, while the median grain count is reduced. Many U-like cells and accumulation of 3H-TdR labeled blasts in early S phase were observed during therapy. The continuous infusion of Ara-c induces striking cytoreduction and concomitantly decreases the 2n-4n percentage and LI. Progressive recovery of 2n-4n percentage and LI over pretreatment values was observed 24-48 hrs after stopping infusion in one case and was probably due to cell recruitment following tumor mass reduction. Our data agree with the literature, which is briefly reviewed, in that they indicate that Ara-c in a low intravenous pulse frequently dose synchronizes the blasts in S phase while higher doses of the drug are more often cytocidal in S phase and cell recruitment can follow cytoreduction.

Adult↗
PubMed1980

Cytokinetic studies on circulating neoplastic cells of Hodgkin's disease.

In two patients with advanced Hodgkin's disease the DNA content, the mitotic index and the in vitro tritiated thymidine labeling index of the neoplastic cells found in peripheral blood, bone marrow and, in one case, in ascitic fluid have been determined. Cytologically the tumor cells were classified into three groups: atypical mononuclear cells, Hodgkin (H) cells and Reed-Sternberg (R-S) cells. Two populations with clearly different kinetic features were recognized. The first one was that of atypical mononuclear cells which exhibited diploid DNA content and proliferative activity of moderate degree: tetraploid cells were, however, observed more frequently than expected. The second population grouped together H and R-S cells, had tetraploid modal DNA content and very high proliferative activity. Hodgkin cells had tetraploid or slightly greater DNA content while R-S cells exhibited also DNA values as high as octoploid and sometimes greater. It can be postulated that by endomitosis some atypical mononuclear cells give origin to H cells and that these assume the monstrous features of R-S cells while increasing their DNA content during the DNA synthesis phase.

Adult↗
PubMedDate not supplied

Cutaneous vasculitis and reactive arthritis following respiratory infection due to Chlamydia pneumoniae: report of a case.

Unlike Chlamydia trachomatis and C. psittaci, the association of C. pneumoniae infection with immunological complications, such as reactive arthritis (ReA) or erythema nodosum (EN) has been rarely reported. Here we present the case history of a patient with C. pneumoniae community acquired pneumonia (CAP) who subsequently developed a ReA and a cutaneous vasculitis. A 45-year-old HLA B27 negative male developed an asymmetric and additive arthritis and a cutaneous leukocytoclastic vasculitis with IgM and complement papillary deposition along hypodermic vessel walls about three weeks after the onset of respiratory symptoms. The diagnosis of chronic Chlamydia pneumoniae infection was based on serology and PCR. Cultural and serological investigations for other infectious agents commonly involved in ReA were negative. This is the first report on the occurrence of two immune-based complications, associated to Chlamydia pneumoniae infection. Therefore, since this infection is very common in our population, although often asymptomatic, should be systematically considered as a common causative agent of ReA and of vasculitis.

Arthritis, Reactive↗
PubMedDate not supplied

Purpura fulminans as clinical manifestation of atypical SLE with antiphospholipid antibodies: a case report.

Purpura Fulminans and DIC were the main clinical manifestations of the antiphospholipid syndrome observed in a 62-year-old man. The patient was well until 44 years of age when he began to suffer from recurrent thrombophlebitis, without other symptoms suggestive of immune disease. At the time of hospital admission the pt. appeared acutely ill, showing high fever, severe anemia, massive urinary blood loss, multiple purpuric patches evolving to hemorrhagic bullae and gangrene rapidly spreading over about 30% of the total body area. No signs of neurological involvement or of visceral thrombotic occlusions were present. Clotting tests were consistent with a diagnosis of DIC, further confirmed by skin biopsy showing the presence of thrombi in dermal arterioles. The autoantibody research was positive as follows: Waaler-Rose 1:40, Anti-DNA 1:80; ANF 1:640, aCA IgG 100 GPL. LA was diagnosed according to standard criteria: prolonged KCT and RVVT not corrected by a mixture of normal plasma and abnormal TTI. Plasma exchange in association with heparin and prednisone was effective in arresting the progression of the skin lesion; nevertheless the patient died ten days after hospital admission for sepsi and acute renal failure.

Autoantibodies↗