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N N Mamaev

Publications and source records attributed to N N Mamaev.

At least 37 records · Page 2Linked to original sources
PubMed1988

[Characteristics of the silver-stained nucleoli in blast elements of various diameters from patients with acute leukemia].

Using silver staining, a study was made of the activity of ribosomal cistrons (RC) in proliferating and non-proliferating subpopulations of bone marrow and peripheral blood blasts, taken from 33 patients with acute non-lymphoblastic leukemia and from 17 patients with acute lymphoblastic leukemia. All the blasts including non-proliferating ones were revealed to synthesize ribosomal RNA (rRNA). The RC activity of large blasts was higher than that of small ones. A significant difference (P less than 0.01) in RC activity between lymphoid and non-lymphoid blasts was found. The relation between nucleolar organizer activity of blasts and their proliferating potentials is discussed, in addition to a possibility for practical use of the above mentioned data.

Bone Marrow↗
PubMed1987

The activity of nucleolar organizer regions of human bone marrow cells studied with silver staining. II. Acute leukemia.

The activity of nucleolar organizer regions (NOR) in chromosomes and interphase nuclei of bone marrow cells from 11 adult patients with acute lymphoblastic leukemia (ALL), 35 patients with acute nonlymphoblastic leukemia (ANLL), and eight healthy donors has been studied with silver nitrate staining. PHA-stimulated lymphocytes of the same individuals were used as standards of the maximum silver-staining patterns for each person. In 90% of patients with acute leukemia the average number of Ag+NOR in metaphases was lower when compared with that of PHA-stimulated lymphocytes. A variable expression of NOR was observed within the cell population and between individual patients. The populations tested showed high heterogeneity in relation to the content of Ag-negative mitoses. Ag+NOR per metaphase and the content of Ag-negative mitoses in bone marrow did not differ between patients with ALL and ANLL. Differences in the staining pattern in leukemic cells are discussed.

Acute Disease↗
PubMed1987

[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.

Adult↗
PubMed1987

[Characteristics of ribosomal RNA synthesis in the blood lymphocytes of chronic lympholeukemia patients].

A study was made of the number of silver grains over the nucleoli and of the content of ribosomes in the lymphocyte cytoplasm for six healthy persons and for 20 patients with chronic lymphatic leukemia. Besides ratios of compact, nucleolonemic and ring types of nucleoli were evaluated in addition to counts of the specific radioactivity of mature 28S rRNA in lymphocytes. In the majority of cases examined, cells with 1 or 2 nucleoli of compact and nucleolonemic types were seen dominating. The number of silver grains over the nucleoli in the control healthy persons did not differ from that in patients who did not receive any treatment, which contrasted with high value grain counts in the treated patients. The lymphocyte ribosome contents varied within the normal and decreased values in both the patient groups. The specific radioactivity in 28S rRNA leukemic lymphocytes was significantly lower in groups of patients with low ribosome contents than in those with the normal ones. The data suggest that in the leukemic cells with a high or unaltered activity of ribosome cistrons and low ribosome levels rRNA processing is broken.

Aged↗
PubMed1986

[Activity of the nucleolar organizers of the cells in epithelial tumors of the human large intestine].

Normal, adenoma and cancer cell nucleoli have been studied by silver impregnation in 13 cancer patients, 48 patients with adenoma (14-tubular, 35-tubulovillous and villous) and 15 controls. It has been shown that the content of silver granules per cell was significantly higher (34.0 +/- 9.7) in cancer cells than in the control (12.3 +/- 3.1). Adenoma cells were heterogeneous. Most villous adenomas, like adenocarcinomas, had high content of Ag granules per cell. The importance of these findings for theoretical and clinical oncology is discussed.

Adenocarcinoma↗
PubMed1986

[Nature of the silver staining and association of acrocentric chromosomes in normal and leukemic human cells].

Silver staining and acrocentric chromosome association (ACA) patterns were investigated in bone marrow cells as well as in peripheral blood cells (cultures with or without PHA) from 39 patients with chronic myelocytic leukemia (CML), including 20 cases being in blastic phase (BP CML), and 51 patients with acute leukemia (AL). Bone marrow cells and PHA-stimulated peripheral blood lymphocytes (from 10 and 17 healthy donors, respectively) were used as a control. The frequency of ACA in metaphases from bone marrow cells of all the above groups of patients was shown to be decreased compared to that in PHA-stimulated lymphocytes. Patients with BP CML and AL constituted the most heterogeneous groups although some of them demonstrated the highest ACA-frequency per cell. There is a pronounced correlation between Ag+-nucleolus organizer regions (NOR's) and the frequency of ACA. With the exception of CML, the correlation coefficients (0.83, 0.74, and 0.72) were highly significant for all the above groups (donors, BP CML, and AL patients, respectively). The distribution pattern of single chromosome pairs, according to their ACA frequency, differed with every individual studied, but it was similar in normal and leukemic cells of the same individual. From the above data a conclusion is made that the frequency of ACA may depend on the functional activity of the NOR's as well as on the cells type.

Acute Disease↗
PubMed1986

[Specific chromosomal changes (aberrations)--supplementary marker of malignant degeneration in oncomorphologic studies].

The paper deals with some methods studying chromosome set in tumour cells. The latest data on tumour chromosome aberrations are reported. The latter are subdivided by the authors into non-specific and specific, characteristic only of certain variants of tumour differentiation, and are of diagnostic significance. The authors put forward further tasks of combined oncomorphologic and cytogenetic studies of specific chromosome aberrations as a valuable marker for the diagnosis of malignancy.

B-Lymphocytes↗
PubMed1985

[Evaluation of the nucleolar organizer activity of tumor cells in patients with esophageal and stomach cancers].

Silver impregnation findings of normal and cancer cell nucleoli are given for 30 cancer patients with esophageal (16) and gastric (14) carcinoma and 5 controls. It has been shown that the content of silver granules per cell (35.3 +/- 2.4) and per nucleolus (13.3 +/- 0.7) in tumor cells were significantly higher than in normal ones (11.4 +/- 1.9 and 5.3 +/- 0.5, respectively). The importance of these findings for clinical oncology is discussed.

Biopsy↗
PubMed1984

[Nucleolar organizer activity of normal and leukemic cells in human bone marrow].

The nucleolus organizer activity of bone marrow cell chromosomes has been studied by silver staining (Howell, Black, 1980) for 6 healthy donors, 24 patients with acute leukemia, and 17 patients with chronic myelocytic leukemia, including 6 cases of blast crisis. In respect to the nucleolus organizer silver staining pattern, bone marrow cells of donors and of patients with leukemias appeared to be more heterogeneous than PHA-stimulated lymphocytes of the same individuals. The average numbers of Ag-stained nucleolus organizers per metaphase in donors (5.2 +/- 0.22), patients with chronic phases (4.9 +/- 0.30), and patients with blast crisis of myelocytic leukemia (5.3 +/- 0.37), and in those with acute leukemia (5.2 +/- 0.46) were lower than those in PHA-stimulated lymphocytes of the same individuals; a great part of bone marrow cell mitoses (from 19 up to 46%) being Ag-negative in all the above groups. A conclusion is made that the heterogeneity in silver staining of the nucleolus organizers in bone marrow cells is due mostly to differences in their mitotic cell maturity degrees. Prospects of employment of silver staining of nucleolus organizers in cells for clinical purposes are discussed.

Acute Disease↗
PubMed1983

Complete or partial trisomy for the long arm of chromosome 1 in patients with various hematologic malignancies.

This study contains data obtained from a cytogenetic investigation of six patients with acute and chronic leukaemia. The karyotypes of bone marrow or blood cells of these patients showed a partial or complete trisomy for the long arm of chromosome 1. Three observations revealed a pronounced resistance of cell clones with 1q+ towards cytostatic therapy, and a comparatively short life span of patients after detection of 1q+. The importance of these changes for the role of some chromosomes and chromosome loci in leukaemogenesis is discussed.

Acute Disease↗
PubMed1983

[Clinical and kinetic characteristics of a temporarily nonproliferating subpopulation of bone marrow blast cells from acute leukemia patients (based on data on DNA autoradiography and cytophotometry].

The morphology of Paramecium bursaria cells, both originally possessing 2 micronuclei (MI), or one MI, has been studied after a local UV irradiation of the germ nuclei. Elimination of one of the MI in bimicronuclear cells usually did not lead to general cytological damage in the UV progeny. Irradiation of MI in the unimicronuclear cells resulted in the following: producing of amicronuclear (MI-) UV subclones, 86% of which appeared to be non-viable. The MI- cells are characterized by the appearance of somatic deciliation and the loss of mobility, disorganization structures of the oral apparatus, the feeding process and the cell division. It is remarkable that the macronucleus (MA) of cells from those cultures displays fragmentation and aberrant division. The structure of MA was changed. Dimensions of the MI- ciliates decreased (by 1.7--1.8 times in average); sometimes these cells had 3--5 contractile vacuoles with one pore. These data suggest that the MI has important role during the vegetative phase of the cell life. Possible asexual cellular functions of the MI and the role of the break of nuclear interactions in the appearance of the morphological damage are discussed.

Acute Disease↗
PubMed1980

[Study of the activity of the nucleolus organizer segments in the chromosomes of normal, leukemic and neoplastic human cells by silver nitrate staining].

The application of a modified Ag-1 method for staining nucleolar organizer regions (NOR) in chromosomes has shown that the total number of AgNO3-stained NOR varies from 6 to 8 in cells of normal individuals as well as in the phytohemagglutinin (PHA) stimulated blood cells of patients suffering from acute leukemia (AL) and chronic myelocytic leukemia (CML). No AgNO3-stained NOR were detected either in non-PHA stimulated blood cells of AL or CML patients, apart from one case of a 48 hours blood culture without PHA from blast crisis CML, where 100 per cent mitotic cells displayed 3-6 AgNO3-stained chromosomes. In a Hela cell line with the modal number equal to 50 and the average number od acrocentrics being 9.3 per cell, the AgNO3-stained NOR numbered constantly 5. In tumor cells from pleural fluid of metastatic ovary tumor patient, with the modal number of cells varying from 50 to 160, the total number of AgNO3-stained NOR increased from 13 to 26 per metaphase. A hypothesis is forward to explain the negative Nor staining property in leukemia, according to which the activities of ribosomal cistrons (rDNA) in the miotic cells of relatively mature granulocytic and erythrocytic cells are either very much reduced or totally arrested.

Acute Disease↗
PubMed1978

[Combined study of leukemic blasts using DNA autoradiography and cytophotometry].

The 3H-thymidine incorporation capacity and DNA contents were studied in the same bone marrow blasts in 4 patients suffering from acute leucaemia. The blast populations were both proliferating and non-proliferating. Actively proliferating cells were blasts of large and medium diameters. Mitotically inactive cells were blasts of medium and small diameters. Cells that stopped dividing were established as being in period G1 of the cell cycle. A high variation in DNA contents was noted in blasts unlabeled with 3H-thymidine, a possible reason of the above phenomenon being discussed.

Adult↗
PubMed1976

[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.

Acute Disease↗