Characteristics of the silver-stained nucleoli of tumor cells from the pleural fluid of lung cancer patients

Tumor cell nucleoli obtained from pleural effusions of 26 patients with different morphologic types of lung cancer were evaluated by silver staining. Distinct heterogeneity of tumor cell populations, with regard to the number of nucleoli as well as their functional activity in respect to ribosomal RNA synthesis, were shown to be the most common feature of all the tumors studied, regardless of their morphologic variants. One likely cause of heterogeneity in Ag nucleolar organized region (NOR) pattern of tumor cells may be due to chromosomal losses and gains from the karyotypes of acrocentric chromosomes with active NORs. Another possible cause for heterogeneity in nucleolar activity might be due to different reactions of tumor cells towards some humoral and cellular factors of pleural fluid including T-lymphocytes.     

Stereoscopic back-scattered electron imaging of silver-stained proteins in nucleoli

By using simultaneously the AgNOR silver staining method, back-scattered electron imaging mode and stereo-tilt in scanning electron microscopy (SEM), it is possible to observe the nucleus through the cell surface, the nucleolus, and the tri-dimensional distribution of the AgNOR-associated acidic proteins. In C3H10T1:2 cells and their 7-12-dimethylbenz--anthracene-treated transformants, the staining demonstrates several intranucleolar silver-staining granules (SSG), surrounded by a weakly staining region. The SSG may represent the fibrillar center (FC) and the weakly staining region, the fibrillar dense component (FD). This component can link several SSG together to form a rope-like structure. In cells with no visible nucleolus and inactive nucleolar organizer regions (NORs) the silver-staining granules are less numerous, close together and the presumed fibrillar dense components are not visible. The SSG are located more peripheraly, and the weakly staining region and the rope-like structure are less prominent in control cell nucleoli than in transformed cells with a comparatively high rate of RNA synthesis.     

Change in morphometric parameters in silver-stained nucleoli from hepatocytes of rats with liver cirrhosis and during rehabilitation from it]

Silver-stained nucleoli of rat hepatocytes were studied in norm, in liver cirrhosis produced by CCl4 poisoning and after cessation of the poisoning. Morphometric parameters of nucleoli were measured using a Videotest computer image analyser. Under cirrhosis the mean number of nucleoli per nucleus was determined to exceed their normal number by 1.27 times. The total volume of nucleoli in the nucleus also exceeded the normal level (by 1.15 times). 3 months after the end of CCl4-poisoning, these parameters decreased almost to normal values. A statistically significant correlation was revealed between the number of nucleoli and their total volume (0.881). Changes of the parameters also correlated with the total protein content in the hepatocytes. Possible reasons for this correlation are discussed. The ratio of the number of chromosomal NORs to the mean number of nucleoli in the nucleus is proposed to be used as a feature for comparative analysis of functional status of nucleoli in the nuclei of different ploidy and in cells of different animal species.     

Measurement of the diameters of nucleoli by the template method

The method of measuring the nucleoli diameters in the light microscope is described. The nucleoli are compared to two standard templates followed by calculation of the means value and the standard deviation by means of special formulas. The scale marks of ocular micrometer or of special ocular scale can be used as the templates. The use of templates makes the measuring of nucleoli diameters 3-3.3 times as quick as the screw ocular micrometer, and with good correlation between the results obtained with both methods, too.     

Experience with using aclarubicin in the treatment of acute leukemia and blast crisis of chronic myeloid leukemia]

The clinical efficacy of aclarubicin, an anthracycline antibiotic, was studied in 48 patients with leukemia. The antibiotic was used in the following combinations with cytarabine: "7 + 7", "5 + 5" and "7 & 3". A complete remission was stated in 14 (42.4 per cent) out of 33 patients with acute nonlymphoid leukemia, 6 (43 per cent) out of the 14 patients having relapses. The combined therapy was effective in 4 out of 5 pre-resistant patients. The "7 + 3" scheme was the most beneficial. The most common adverse reactions were nausea and vomiting.     

Differences in the localization of Alu-repeats in various chromosomes of peripheral blood cells from normal donors and bone marrow cells from patients with acute leukemia

The dispersion of the Alu-family DNA repeats in phytohemagglutinin-stimulated lymphocytes from peripheral blood of normal donors as well as in nonstimulated bone marrow cells of four patients suffering from acute leukemia was studied by hybridization on metaphase chromosomes in situ. DNA of bacteriophage lambda CAR42 clone containing the insertion of at least 8 copies of Alu-family DNA-repeats and labelled with tritium was used as a probe in hybridization. All patients with acute leukemia had the same pattern of changes in hybridization of the bone marrow cells. It consists of silver grains clustering over 3q26, 8p12, 14q24. The pattern may reflect amplification transposition of Alu-family DNA repeats in the human genome connected with cellular differentiation or malignant transformation of blood cells.     

Hydrocortisone in culture protects the blast cells in acute myeloblastic leukemia from the lethal effects of cytosine arabinoside

The blast cells in acute myeloblastic leukemia (AML) respond to many of the same regulatory mechanisms that control normal hemopoiesis. These include the growth factors that bind to membrane receptors and steroid hormones or vitamins that have intracellular receptors. We report the effects in culture of the steroid glucocorticoid hydrocortisone on freshly explanted AML blasts from patients and on two continuous AML cell lines. Only small changes in clonogenic cell numbers in suspension cultures were seen in the presence of hydrocortisone. The most striking effect of the hormone was on the sensitivity of blasts cells to cytosine arabinoside (ara-C). In contrast to the response of AML blast cells to retinoic acid, a ligand for intracellular steroid receptors that sensitizes some blast populations to ara-C, hydrocortisone reduced the toxic effects of the drug. The protective action of hydrocortisone was not mediated through the cell cycle since exposure of blasts to hydrocortisone did not affect the percentage of cells in DNA synthesis as measured with the tritiated thymidine (3HTdR) "suicide" technique. The hydrocortisone effect could be demonstrated using a pulse (20 min) exposure protocol. Blasts pulsed with increasing specific activities of 3HTdR showed the usual response pattern with an initial loss in plating efficiency to about 50% of control, followed by a plateau, regardless of whether the cells had been exposed to hydrocortisone. Control blasts exposed to increasing ara-C concentrations gave very similar dose-response curves; in striking contrast, blast cells cultured in hydrocortisone, then pulsed with ara-C did not lose colony-forming ability even though the same population was sensitive to 3HTdR. The hydrocortisone effect was dose and time related; protection from ara-C increased from 10(-8) to 10(-5) M and was seen after 4 hr exposure but required 8 hr to reach a maximum. We conclude that hydrocortisone can protect blasts from the lethal effects of ara-C even while the cells are in active DNA synthesis.     

Blood lymphocyte volumes and diameters in patients with chronic lymphocytic leukemia and normal controls

The electronic modal lymphocyte volumes of 151 patients with chronic lymphocytic leukemia (CLL) and 305 normal controls were determined by the hydrodynamically focused multi-channel Coulter TF analyser. The mean volumes of the normally distributed groups were 166 +/- 19.3 (range 126-216) fl in patients with CLL and 206 +/- 14.4 (range 126 +/- 246) fl in normal controls. The calculated cell diameters were 6.8 (6.2-7.4) micron and 7.3 (6.8-7.8) micron respectively. Our data do not support previous reports about relations between cell size and clinical stages of the Rai and Binet classifications.     

Number of nucleoli in various cell types of the mouse

The nucleoli of cells of the adult mouse were examined by staining with toluidine blue after removal of deoxyribonucleic acid from tissue sections by deoxyribonuclease treatment. The nuclei of each cell type examined contained one or more nucleoli. This was observed even in lymphocytes and neuroglia, although these cells have occasionally been described as anucleolated. In mature spermatids and spermatozoa, however, it was not possible to detect a nucleolus. The distribution of the number of nucleoli in many diploid cells exhibited a mode of two or three nucleoli per nucleus, and a range from 1 to 6 nucleoli. In presumedly diploid hepatic nuclei, the maximum number of nucleoli was six; but in presumedly tetraploid hepatic nuclei, it was 11. Thus, nearly twice as many nucleoli are present when the chromosome number is doubled. In view of this observation, it is suggested that six nucleolar organizers are present in the diploid chromosomal complement of the mouse. However, through failure of some nucleolar organizers or more probably through fusion of nucleoli, the number of these organelles in most nuclei is less than six.     

Characteristics of DNA replication of the chromosomes of the bone marrow cells in patients with acute leukemia]

A study of the late DNA replication pattern in chromosomes of human acute leucaemia cells revealed a significant diffrence from control. Chromosomes, 2,3 and 4-5 of the acute leucaemia cells finish their DNA replication earlier, and chromosomes 1, 13-15 and 16 later, compared to the control chromosomes. The difference in the pattern of DNA replication between analogous chromosomes of acute leucaemia and donor cells was associated with the discovery of large late-replicating chromatin blocks in the pericentromeric regions of leucaemia cell chromosomes. Some relationship is suggested between the pattern of pericentromeric heterochromatin DNA replication and cell differentiation.     

Risk factors occurring in various types of acute leukemia

The present investigations demonstrate that as far as the genesis of non-lymphatic leukemias is concerned environmental factors may be assumed as an aetiological factor to an increasing extent. Medicaments, particularly cytostatics, exogenous noxious occupational agents and infectious-inflammatory diseases might be significant for developing ANLL, whereas virus infection, immunizations, and acclimatization to specific conditions of climate may be rather attributed as risk factors for ALL. A tendency to deviations from the blood picture ( lymphomonocytosis , leukocytopenia, toxic granulation of neutrophilic granulocytes) can be increasingly observed in workers engaged in chemical industry, with these changes, being still reversible. A permanent effect of exogenous toxic agents, however, will produce a serious damage of the bone-marrow. Further investigations are provided for elucidating the function of different haemopoietic cell systems, particularly the immune status, in workers of those enterprises where an exposure to noxious substances can be found.     

Human deoxycytidine kinase. Purification and characterization of the cytoplasmic and mitochondrial isozymes derived from blast cells of acute myelocytic leukemia patients.

A procedure for purifying human cytoplasmic and mitochondrial deoxycytidine kinase (NTP:deoxycytidine 5'-phosphotransferase, EC 2.7.1.74) was developed. Both purified isozymes have a similar molecular weight, activation energy and catalyze the reaction by a sequential mechanism. These two isozymes differ with respect to their substrate specificities. With cytoplasmic deoxycytidine kinase, ATP, GTP and TTP have the highest reaction velocity. Pyrimidine nucleoside triphosphates have higher affinity but lower V than purine nucleoside triphosphates. Cytidine and arabinosylcytidine can serve as substrates. With mitochondrial isozyme only ATP gives the highest reaction velocity. ATP and dATP have the same Km but different V values. Besides deoxycytidine, also deoxythymidine but not cytidine or arabinosylcytidine can serve as substrates. There are also differences between these two isozymes with respect to their sensitivity to inhibition. For cytoplasmic enzyme, Br5dCyd and Iodo5dCyd are not inhibitory. Both dCTP and UTP are competitive inhibitors (Ki 0.25 and 0.5 micronM, respectively) with respect to ATP. For mitochondrial isozyme both Br5dCyd and Iodo5dCyd are inhibitory and dCTP and TTP are competitive inhibitors (Ki 2 and 10 micronM, respectively) with respect to ATP.     

In vitro autologous blast cell sensitization as immunotherapy in acute non-lymphocytic leukemia

Summary Remission mononuclear cells incubated in vitro for 96 h with autologous stored blast cells were reinfused IV on two occasions as adjuvant maintenance therapy. The procedures were well tolerated, but in vitro response to the blast cells was negligible.The present mean duration of complete remission (15.7 months) appears to be similar to that of 28 patients (12.4 months) treated at the same time with chemotherapy alone by the same physicians.