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Biomedical subjects

G Palka

Publications and source records attributed to G Palka.

At least 91 records · Page 5Linked to original sources

Cytogenetic survey of 31 patients treated with bone marrow transplantation for acute nonlymphocytic and acute lymphoblastic leukemias.

The authors report on a sequential cytogenetic study carried out on 31 patients with acute leukemia (20 with acute lymphoblastic leukemia and 11 with acute non-lymphocytic leukemia) who underwent bone marrow transplantation (BMT). Engraftment was documented in all patients with sex-mismatched donors and with donor constitutional aberrations. During the follow-up, ranging from 6 to 110 months, clinical and hematologic relapse was observed in 11 patients (35.5%). Five of these cases showed a normal karyotype, 3 were of undefined relapse origin, 2 were aneuploid karyotypes, and one was donor (male) metaphases. Cytogenetic and immunologic data in the latter patient were suggestive of relapse in donor cells.

Adolescent↗

In situ Hpa II endonuclease digestion on fixed chromatin of solid tumor cells.

Neoplastic cells from different tumors (lung, colon, rectal, and pancreatic carcinoma, synovial sarcoma, and Wilm's tumor) were fixed on slides and in situ digested with Hpa II and Msp I restriction enzymes. Staining of samples with the DNA specific fluorochrome ethidium bromide showed a clearcut decreased fluorescence after Hpa II digestion in neoplastic cells as compared to normal controls, whereas Msp I digestion produced the same pattern in neoplastic and in normal cells. The authors hypothesize that the altered state of methylation in neoplastic cells could affect the Hpa II activity on fixed chromatin.

Chromatin↗

Growth delay in Down syndrome and zinc sulphate supplementation.

Children affected with Down syndrome (DS) show deficient growth, immunodeficiency--especially concerning the T-cell population--and low plasma zinc levels. New growth charts have been recently proposed, and zinc supplementation to the diet has been reported to improve transiently the efficiency of the immune system. The aim of this study was to evaluate if in DS children zinc sulphate therapy could improve the growth rate and affect some endocrine parameters. We studied 22 patients (16 males and 6 females) who received zinc sulphate for 6 to 9 months. Fifteen of 22 patients studied reached a higher centile in their growth rate, whereas the remaining seven showed no change, at least to date. The average height velocity changed from 23.84 +/- 7.98 mm/6 months to 40.80 +/- 7.68 mm/6 months. Growth hormone serum level was 5.94 +/- 4.89 ng/ml compared with 7.49 +/- 6.75 ng/ml before and after therapy, respectively. Somatomedin serum level was 160.27 +/- 68.88 mU/ml and 205 +/- 124.07 mU/ml before and after therapy, respectively. In conclusion, zinc sulphate therapy of patients with DS affects not only the immune system, as previously reported, but can also accelerate growth.

Adolescent↗

Cytogenetic study of the heterochromatic polymorphisms in 100 subjects with Down syndrome and their parents.

We report on a cytogenetic study of 100 subjects with Down syndrome (DS), diagnosed from 1980 to 1988, and their parents. Free trisomy was present in 95% of the patients; 5% had trisomy due to an unbalanced translocation. Approximately 60% of patients were born to mothers younger than age 35 years, the highest number of DS births being in the group of mothers between ages 25 and 29 years. These findings are clearly related to the higher number of pregnancies in this group. However, the prevalence of DS births increased significantly in women older than age 35 years, as expected. A cytogenetic study of heterochromatic polymorphisms showed a significant increase of polymorphisms in DS children and in their parents, mostly in mothers, compared with a control group. Since heterochromatic blocks of acrocentric and nonacrocentric chromosomes are frequently associated during interphase, we discuss a possible correlation between nondisjunction and heterochromatic polymorphism.

Adult↗

Karyotypic changes identified by HaeIII restriction endonuclease banding in a patient with M2 acute non-lymphoblastic leukemia.

A patient with acute non-lymphoblastic leukemia, FAB type M2, showed a complex karyotype involving chromosomes 1 and 11. The breakpoints could not be exactly identified by GTG and QFQ banding. A subsequent analysis with Alul and HaeIII restriction enzyme staining allowed the detection of a translocation of the heterochromatic region of chromosome 1 to 11q21.

Aged↗

Cytogenetic survey of sixty-one patients with preleukemic syndrome including myeloproliferative and myelodysplastic diseases.

The authors report on a cytogenetic survey of 61 patients with preleukemic syndrome (PLS). Of these, 41 had a myeloproliferative disease (MPD) and 20 a myelodysplastic syndrome (MDS). Clonal chromosome abnormalities appeared in 24 patients (39.3%) at disease onset. Such changes had a frequency of 26.8% in patients with MPD and 65% in those with MDS. The authors stress the usefulness of ethidium bromide high resolution techniques. They allow obtaining a larger number of metaphases and elongated chromosomes with higher banding resolution and could account for the frequent detection of chromosome changes in most groups of MDS patients in the present series. Moreover, they discuss the possible significance of some chromosome aberrations suggesting that patients with MPD may live longer than those with MDS because of their higher frequency of normal karyotypes.

Adult↗

Is zinc deficiency a cause of subclinical hypothyroidism in Down syndrome?

In Down syndrome there is a high incidence of overt or subclinical hypothyroidism as well as some immunological defects, early thymic involution associated to low serum zinc levels. Zinc supplementation to the diet has been reported to transiently improve thymic function; moreover thymic function has been shown to be in relation with the pituitary-thyroid axis. The aim of this study was to evaluate if, in Down patients, zinc therapy could improve also thyroid function, by determining serum levels of total and free thyroid hormones and basal TSH levels. In 52 patients studied, we found a high incidence of subclinical hypothyroidism (30%); in 17 patients treated with zinc sulphate we showed a reduction of FT3. More significantly, we detected 9 patients with low zinc levels in which zinc supplementation improved thyroid function, thus reducing the incidence of subclinical hypothyroidism.

Adolescent↗

Hinf I restriction endonuclease digestion on human fixed metaphase chromosomes.

The authors report on the activity of Hinf I restriction endonuclease on human fixed metaphase chromosomes. Experiments performed by digesting chromosomes just after harvesting or after ageing in methanol-acetic acid displayed a different pattern of digestion on metaphases, since only aged preparations showed gaps on heterochromatic regions of chromosomes 1, 9 and 16 and C-like bands on other chromosomes. In this view, the authors suggest that structural modifications of the DNA, induced by acid fixation, can influence Hinf I activity on fixed metaphase chromosomes.

Chromosomes↗

Cytogenetics in patients with chronic myelogenous leukemia treated with bone marrow transplantation.

Cytogenetic data are reported from 16 patients with Philadelphia chromosome (Ph) positive chronic myelogenous leukemia (CML) treated with bone marrow transplantation (BMT). The usefulness of cytogenetic investigations for the assessment of marrow engraftment is stressed. The significance of persistence or reappearance of Ph after BMT, possibly due to a defective leukemic clone eradication by the conditioning regimen, is also discussed. Generally, Ph-positive cells are damaged and disappear within the first year of BMT. Sometimes, however, the cells may repair the damage and proliferate again, resulting in disease relapse. Rarely, clinical and hematologic relapse does not follow Ph-positive clone expansion although leukemic cells represent more than 50% of marrow metaphases examined. Finally, the effect of interferon on Ph-positive clones after BMT and random chromosome changes, that appear transiently after BMT and are of uncertain significance, are discussed.

Adolescent↗

A new case of partial 2p trisomy due to de novo interstitial duplication 2p21-22.

We report on a case of "de novo" interstitial duplication of bands 2p21-22 in a 31-month-old female with mild mental retardation and dysmorphism. Cytogenetic investigations were performed on peripheral blood by adding 5-BrdU and 5-FdU. Measurements of enzymatic activity of malate dehydrogenase, whose gene has been mapped on the band 2p23, added reliability to the identification of bands 2p21-22 as the duplicated segment. The authors suggest that the duplication of this segment is able to cause the clinical picture of the syndrome of partial 2p trisomy.

Abnormalities, Multiple↗

Effect of HpaII and MspI restriction endonucleases on chronic myelogenous leukemia chromosomes. Detection of CpG dinucleotide demethylation in situ.

The restriction endonucleases HpaII and MspI both cleave the nucleotide sequence CCGG, but the action of HpaII is inhibited if the internal cytosine is methylated. HpaII and MspI were used on fixed chromosomes from bone marrow cells of individuals suffering from chronic myelogenous leukemia and healthy individuals. We found that MspI acts with the same efficiency on all chromosome samples, whereas HpaII extracts more DNA from the chromosomes of leukemic individuals than from the chromosomes of nonleukemic individuals. We postulate that demethylation of cytosine in the CpG dinucleotide of leukemic cell DNA accounts for our findings.

Cytidine Monophosphate↗

A new case of chronic myelogenous leukemia with 14q+ marker and review of the literature.

We report a new case of Ph 1 positive chronic myelogenous leukemia (CML) with 14q+ marker shown during chronic phase (CP) and subsequently in blastic crisis (BC). After a review of the literature, we discuss the biological significance of 14q+ marker in developing lymphoid cellular differentiation, during evolution of CML, that remains still unclear. Besides, we also discuss the prognostic value of this change, concluding that a larger number of cases may clarify this question, as also the unresponsivity to chemotherapy of the patient studies so far, may not be related to 14q+ marker.

Adult↗

[Cytogenetic study of 140 patients with changes in sexual features].

Cytogenetic studies on a group of 140 patients with alterations of sex features (sex uncertainty, gynecomasty, menstrual abnormality and so on) confirmed a high incidence of chromosome abnormalities (25%). Most frequent abnormal kariotypes were X0 and XXY. Furthermore, cytogenetic investigations showed a higher rate of heterochromatic polymorphism in patients (33.7%) than in controls (13.4%), the most frequent being 1qh, 9qh and 16qh. A possible role of heterochromatic polymorphism in determining sex chromosome abnormalities or, directly, sex diseases, and in possibly enhancing neoplastic risk, is suggested.

Adolescent↗

Chromosome changes in 19 patients with Waldenström's macroglobulinemia.

We report on 19 patients with Waldenström's macroglobulinemia (WM) who were studied cytogenetically at the onset and during progression of the disease. We found a high frequency of chromosome changes confirming the claim of other authors that, during progression of the disease, a large number of residual neoplastic cells, insensitive to conventional chemotherapy, persist. In turn, this may be the cause of the difficulty of inducing remission (21% of cases) and of the short survival (mean, 35 months). In our experience it is difficult to identify the primary chromosome abnormalities because of the late clinical stage at which the chromosomes were examined. However, changes involving chromosomes #10, #11, and #12 may be unfavorable events in patients with WM.

Adult↗