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M Rozman

Publications and source records attributed to M Rozman.

At least 55 records · Page 3Linked to original sources
PubMed1993

[The adaptation of human bone marrow adipose tissue to various degrees of hematopoietic cellularity].

PURPOSE: To assess whether the variations in the number and size of the adipocytes are proportional, or not, to the changes of the fat tissue fraction (FF) associated to different degrees of hematopoietic cellularity of the bone-marrow. MATERIAL AND METHODS: The material was made up of 28 specimens of bone marrow biopsy, from which 265 microscopic fields representing a wide range of FF were obtained. As index of proportionality, the ratio N/S (adipocyte number/size) was employed. RESULTS: The parameters FF and N/S showed a highly significant correlation (r = 0.89; p = 0.00000003) at low-normal FF range (< 40%), whereas at high FF range (> 40%), such a correlation was lacking (r = 0.01; p = 0.86). CONCLUSION: At low-normal FF the adipocyte number and size vary proportionally. Conversely, at high FF, in some cases a more marked increase of number and in other instances of adipocyte size is detected. Further investigations are needed to find out the responsible factors for this different behaviour.

Adaptation, Physiological↗
PubMed1993

Sequential study of myeloid differentiation antigens of neutrophil granulocytes in different phases of chronic myeloid leukaemia: natural history and prognostic significance.

In an attempt to contribute to the knowledge of the natural history of Philadelphia-chromosome-positive chronic myeloid leukaemia (CML) and its prognosis, we analyzed sequentially the myeloid differentiation antigens of peripheral blood neutrophil granulocytes (NG) in different evolutive stages of the disease. Four monoclonal antibodies (CD15, CD24, 31D8, and 13F6) were used, and a total number of 116 sequential studies were performed in 43 patients. At diagnosis, there is a significant decrease of NG expressing myeloid differentiation antigens, which recover to nearly normal levels after initial control of the disease. The onset reduction is probably due to the circulation of incompletely mature NG. In accelerated/blastic phase NG expressing myeloid differentiation antigens decrease again, probably due to a true antigen loss. This reduction could herald by a few months the development of accelerated/blastic phase. In such a case, its predictive strength is higher than that of the well recognized initial prognostic parameters in CML. These results indicate that the sequential study of NG myeloid differentiation antigens may contribute to both a better understanding of the natural history of CML and the evolutive prognosis of this disease.

Adult↗
PubMed1993

[Adaptation of human bone marrow adipose tissue to different grades of hemopoietic cellularity].

PURPOSE: To assess whether the variations in the number and size of the adipocytes are proportional, or not, to the changes of the fat tissue fraction (FF) associated to different degrees of hematopoietic cellularity of the bone-marrow. MATERIAL AND METHODS: The material was made up of 28 specimens of bone marrow biopsy, from which 265 microscopic fields representing a wide range of FF were obtained. As index of proportionality, the ratio N/S (adipocyte number/size) was employed. RESULTS: The parameters FF and N/S showed a highly significant correlation (r = 0.89; p = 0.00000003) at low-normal FF range (< 40%), whereas at high FF range (> 40%), such a correlation was lacking (r = 0.01; p = 0.86). CONCLUSION: At low-normal FF the adipocyte number and size vary proportionally. Conversely, at high FF, in some cases a more marked increase of number and in other instances of adipocyte size is detected. Further investigations are needed to find out the responsible factors for this different behaviour.

Adipose Tissue↗
PubMed1992

Dyserythropoiesis in iron-deficiency anemia: ultrastructural reassessment.

Iron deficiency is usually included among the causes of acquired dyserythropoiesis. This concept was derived mainly from light microscopic studies. To reassess such a notion at ultrastructural level, a transmission electron microscopic evaluation of bone marrow was performed in seven patients with iron-deficiency anemia. In contrast to the widely accepted concept, derived from light microscopic studies, only a small proportion (2-4%, not different from controls) of erythroblasts displayed some of the features of nuclear dyserythropoiesis. On the contrary, when examining the cytoplasm, we found a significantly increased number of void ropheocytotic vesicles in the majority of late erythroblasts as compared to controls (P less than 0.001). This feature may be considered as an ultrastructural marker of iron deficiency and is consistent with the present knowledge on transferrin-mediated delivery of iron to the cell.

Adolescent↗
PubMed1992

[Stereological study of the fat cells in bone marrows with a heterogeneous distribution of adipose tissue].

PURPOSE: 1) To analyze to what extent the fat tissue fraction of the human bone marrow with heterogeneous distribution depends on size and number of adipocytes. 2) To infer the influence of local factors on the two aforementioned parameters. MATERIAL AND METHODS: The material was made up of 15 specimens of bone marrow biopsy with markedly heterogeneous distribution of fat tissue, alternating normal or hyperplastic zones (area I) with aplastic ones (area II). The method of study was the stereological technique on plastic-embedded specimen sections. RESULTS: In the area II, with a fat tissue fraction markedly higher than in area I, both adipocyte number and size were significatively increased. The fat tissue fraction difference (Dif FRGR) between both areas was significatively correlated with the difference of the adipocytes number (Dif Nv) but not of the size (Dif D). However, in multiple regression both Dif Nv and Dif D contributed significatively to Dif FRGR. CONCLUSIONS: Since the histopathological pattern investigated in this work represents a model caused by intervention of local factors, it can be concluded that these can modify both the size and number of adipocytes.

Adipose Tissue↗
PubMed1992

[Granulocyte alkaline phosphatase activity in the chronic phase and blastic crisis of chronic myeloid leukemia. Sequential study of 43 patients].

PURPOSE: To evaluate in a sequential fashion the activity of the leukocyte alkaline phosphatase (LAP) in the chronic phase and the blastic crisis of chronic myelogenous leukaemia (CML). MATERIAL AND METHODS: This study is comprised of 43 patients diagnosed of CML according to standard criteria. The initial LAP scores were compared with those recorded in the blastic crisis, using cytochemical methods. The statistical analysis was performed with Student's test and chi-square. RESULTS: The LAP activity at diagnosis was low in 40 of the 43 cases (93%), the score being 0 in 20 instances. In the blastic crisis low scores were found in 27 patients (63%), while LAP activity appeared normal or increased in 16 others (37%). When the LAP scores of the two phases of the disease were compared the differences were found statistically significant (p less than 0.0001 and p less than 0.0007, respectively). CONCLUSIONS: These results confirm that the onset of the blastic crisis of CML is often accompanied by an increase of the LAP activity, although this last persists low in the majority of the patients.

Adolescent↗
PubMed1991

A study of the myeloid differentiation antigens of the peripheral blood neutrophil granulocytes in the different evolutive phases of chronic myeloid leukemia.

To ascertain whether progression from the chronic to the accelerated and blastic phases of chronic myeloid leukemia (CML) is associated with the loss of the myeloid differentiation antigens of the neutrophil granulocytes (NG), we analyzed two monoclonal antibodies (PMN 31D8 and PMN 13F6) recognizing normal peripheral blood NG membrane antigens in 49 patients in different evolutive stages of CML. Since five patients were studied twice, a total of 54 studies were carried out. Fourteen patients were evaluated at diagnosis, 12 in the controlled chronic phase within 1 year from diagnosis, 14 in the advanced chronic phase (median evolution 3.25 years), and 14 in the accelerated (five cases) or blastic (nine cases) phases. Fourteen normal subjects served as a control group. At diagnosis, a significant decrease in the positivity for both antigens was observed with respect to controls, probably due to the circulation of incompletely mature NG. In the early chronic phase the values were within the normal range, whereas a significant decrease was registered in the advanced chronic phase and especially in the accelerated/blastic phase. A negative correlation between the NG positivity for both markers and the time elapsed from the moment of obtaining the initial control of the disease was found, suggesting that a progressive loss of the myeloid antigens of the NG occurs during the evolutive course of CML. These results seem to confirm the usefulness of the NG myeloid differentiation antigen study as an evolutive parameter in CML.

Antibodies, Monoclonal↗
PubMed1990

Variations of fat tissue fraction in abnormal human bone marrow depend both on size and number of adipocytes: a stereologic study.

Studies dealing with the number or size of individual adipose cells in abnormal human bone marrow are lacking. To ascertain whether variations in fat tissue fraction depend on the size of individual adipocytes or their number or both, a stereologic study of 30 human bone marrow specimens (10 with aplasia, 10 with hyperplasia, and 10 with dysplasia) was performed. A total of 23,435 adipocyte profiles were measured and two stereologic parameters were obtained in each specimen: mean diameter and number of cells per mm3 of bone marrow. The fat tissue fraction correlated positively with the size (r = .79; P less than .001) and the number/volume (r = .77; P less than .001) of adipocytes. The significance of both adipocyte size and adipocyte number/volume was confirmed by stepwise multiple regression, in which the size alone explained 62.5% of fat tissue fraction and both size and number/volume explained 95.8% of fat tissue fraction. These results are discussed from a pathophysiologic point of view.

Adipose Tissue↗
PubMed1990

[Blast crisis of chronic myeloid leukemia with positive Philadelphia chromosome: course and clinico-hematologic profile in 80 patients].

The major initial clinical, hematological and cytogenetical features of a series of 80 patients with blastic crisis (BC) in chronic myelocytic leukemia with positive Philadelphia chromosome (Ph) were evaluated, and also were their outcome and response to therapy. Mean age of patients was 45 years (SD: 14.3). Ten patients fulfilled the criteria for initial BC, and 14 had extramedullary blastic infiltration. In one third there was an acceleration phase before the development of BC. The mean leukocyte count was 69 (SD 75) X 10(9)/l. In 40% there was anemia with hemoglobin less than 90 g/l, and 37.5% had thrombopenia with less than 100 X 10(9) cells/l. In most patients, serum lactic dehydrogenase activity was increased, and in one fourth the index of granulocyte alkaline phosphatase was high. In 9 patients, blast cells had a lymphoid phenotype and in 47 (59%) cytogenetic abnormalities in addition to Ph chromosome were found, usually consisting of 8 trisomy, duplication of Ph chromosome, and the presence of a 17q isochromosome. The median survival of the series was 4.8 months. When analyzed as a time-dependent variable, the achievement of a favorable therapeutic response (found in 26% of patients) was associated with a longer survival.

Blast Crisis↗
PubMed1990

A study of prognostic factors in blast crisis of Philadelphia chromosome-positive chronic myelogenous leukaemia.

In 80 patients with Ph-positive chronic myelogenous leukaemia the main clinical, haematological and cytogenetical data were recorded at diagnosis of blast crisis and evaluated for prognostic significance. At the time of the analysis 73 patients had died, with a median survival of 4-8 months from diagnosis of blast crisis for the whole series. When analysed as a time-dependent variable, the achievement of a favourable response to chemotherapy resulted in a longer patient's survival. On the other hand, the univariate analysis identified six pretreatment characteristics associated with a poorer prognosis: a longer chronic phase, presence of extramedullary blastic involvement, a platelet count below 200 x 10(9)/l, a less marked leucocytosis, a blood blast cell percentage higher than 10%, and presence of trisomy 8. The latter parameters were included in a multiple regression model together with the blast cell phenotype (lymphoid versus non-lymphoid), and only four of them (trisomy 8, duration of chronic phase, platelet count, and leucocyte count) retained their prognostic influence. When the therapeutical response was also included in the regression model, it proved to be the most important prognostic variable, followed by trisomy 8, length of chronic phase, extramedullary disease, and platelet count, whereas the leukocyte count lost its predictive value. Thus, in spite of the short overall survival of blast crisis patients, the identification of prognostic factors in such a haematological condition may be of interest, especially in the interpretation of new therapeutical approaches.

Adult↗
PubMed1990

[Treatment with cyclosporin A of the anemia associated with chronic lymphatic leukemia].

The anaemia accompanying chronic lymphocytic leukaemia (CLL) may have different causes (bone marrow infiltration, hypersplenism, immune haemolysis, haemorrhages) and is one of the poor-prognosis features of the disease. Treatment of advanced CLL patients with tumoral-infiltrative anaemia is based on chemotherapy. Nevertheless, some proofs seem to stress the important role played by suppressor T cells on the mechanism of the anaemia in such patients. As a result of these observations, cyclosporin A, a drug with proven efficacy in autoimmune diseases and bone marrow insufficiency, is being used in these cases. Three patients with advanced B-CLL and anaemia, refractory to treatment, received cyclosporin A (8-10 mg/kg, p.o. daily for 2-4 months). One of them recovered from anaemia and thrombocytopenia and is still in this situation after 11 months of suppression of therapy. Two other such cases are revised from the literature, as well as the role played by cyclosporin A in the therapy of CLL.

Adult↗
PubMed1990

[Treatment of multiple myeloma using vincristine, cyclophosphamide, melphalan and prednisone (VCMP). Long-term results in 63 patients].

The results achieved in a series of 63 patients diagnosed of multiple myeloma in one Centre between February 1981 and December 1984 are reported. One patient was in stage IA, 27 in stage II (A, 24; B, 3), and the remaining 35 were in stage III (A, 22; B, 13). The initial therapy consisted of courses of vincristine, cyclophosphamide, melphalan and prednisone combination chemotherapy (VCMP) given every 4th week. Among the 56 patients who were evaluable, 28 (50%) showed objective response, 6 (10.7%) clinical improvement, and therapeutical failure was seen in 14, whereas 8 patients died during the first two months of treatment. The haematological tolerance to VCMP was acceptable, but neurotoxicity due to vincristine appeared in 17.8% of the cases. Thirty-two patients showing resistance to VCMP at any given moment received vincristine, BCNU, adriamycin and prednisone or dexamethasone (VBAP/D) as salvage therapy, only 5 responses (15.6%) being achieved. Only 5 patients are still alive and the median survival of the series is 23 months. Progression of the disease and infections were the major causes of death.

Antineoplastic Combined Chemotherapy Protocols↗