A developmentally modulated chromatin structure at the mouse immunoglobulin kappa 3' enhancer.

Transcription of the mouse immunoglobulin kappa gene is controlled by two enhancers: the intronic enhancer (Ei) that occurs between the joining (J kappa) and constant (C kappa) exons and the 3' enhancer (E3') located 8.5 kb downstream of the gene. To understand the role of E3' in the activation of the mouse immunoglobulin kappa gene, we studied its chromatin structure in cultured B-cell lines arrested at various stages of differentiation. We found that 120 bp of the enhancer's transcriptional core becomes DNase I hypersensitive early in B-cell development. Genomic footprinting of pro-B and pre-B cells localized this chromatin alteration to B-cell-specific protections at the region including the direct repeat (DR) and the sequence downstream of the DR (DS), the PU.1-NFEM-5 site, and the core's E-box motif, identifying bound transcription factors prior to kappa gene rearrangement. Early footprints were, however, not detected at downstream sites proposed to play a negative role in transcription. The early chromatin structure persisted through the mature B-cell stage but underwent a dramatic shift in plasma cells, correlating with the loss of guanosine protection within the DR-DS junction and the appearance of novel footprints at a GC-rich motif upstream and the NF-E1 (YY1/delta)-binding site downstream. Gel shift analysis demonstrated that the DR-DS junction is bound by a factor with properties similar to those of BSAP (B-cell-specific activator protein). These results reveal developmental-stage-specific changes in the composition of nuclear factors bound to E3', clarify the role of factors that bind constitutively in vitro, and point to the differentiation of mature B cells to plasma cells as an important transitional point in the function of this enhancer. The observed changes in nuclear factor composition were accompanied by the rearrangement of positioned nucleosomes that flank the core region, suggesting a role for both nuclear factors and chromatin structure in modulating kappa E3' function during B-cell development. The functional implications of the observed chromatin alterations are discussed in the context of recent studies on kappa E3' and the factors that bind to it.

[Treatment of acute lymphoid leukemia (ALL) in the child]. / Tratamiento de la leucemia linfoide aguda (LLA) en el niño.

PURPOSE: To analyse the results of the therapy administered to children with ALL in Cuba. PATIENTS AND METHODS: Four-hundred and twenty-five children (aged below 15 years), diagnosed of ALL in 8 different Cuban hospitals between 1973 and 1991, were evaluated. Five different therapeutic regimes were used: three "classic" GLATHEM protocols in the first period (1973-1981) and two intensive BFM-like protocols in the second period (1982-1991). The Kaplan-Meier method was applied for survival analysis, and the differences were evaluated by the log-rank and Mantel-Cox methods. RESULTS: Two-hundred and sixty-five patients were included in the first period, 81 with low-risk disease, 133 with standard risk and 51 with poor-risk leukaemia. The second period comprised 160 cases, 50 of low-risk, 83 with standard risk and 27 with poor-risk leukaemia. The disease-free survival probability at 60 months was 35% for the first group and 55% for the second (p < 0.0001). The 60-month survival (SV) as a whole was 45% for the "classic" treatments and 60% for the BFM-like protocols (p < 0.01). The disease-free survival (DFS) probability for each prognostic group was as follows: 50% for low-risk, 43% for standard risk, and 25% for poor-risk (p < 0.001) and the probability of survival as a whole was, respectively, 65%, 49% and 28% (p < 0.001). as for this compilation, 172 patients were out of any treatment for periods ranging between 14 and 168 months. CONCLUSIONS: 1) The percentage of remissions was similar for both groups of treatments. 2) The results attained with BFM-like protocols were better than those of the "classic" therapy with regard to the SV and DFS differences. 3) Significant differences can be appreciated between good- and poor-prognosis groups for both types of treatment.

[Incorporation of transferrin into the erythron in anemic and polycythemic conditions]. / Incorporación de la transferrina al eritrón en estados anémicos y policitémicos.

A ferrokinetic study was performed in 79 patients, 25 with absolute polycythaemia, 19 with relative polycythaemia and 35 presenting anaemia of different aetiology. The incorporation of transferrin into the erythron (ITE) was estimated on each case. The mean ITE values found in absolute primary and secondary polycythaemia and in secondary polycythaemia were, respectively, 281 +/- 85, 181 +/- 99 and 74 +/- 19 mumol/L tb/d (i.e., micromoles per litre of total blood per day). The mean ITE in iron deficiency anaemia was 110 +/- 43 mumol/L tb/d, in haemolytic anaemia this was 274 +/- 151 mumol/L tb/d, and in patients with myelodysplastic syndromes such values was 116 +/- 49 mumol/L tb/d. Significant differences were found for each group of patients with respect to a normal control group. Such findings are in accordance with the pathophysiology of the different pathologies studied. The values found in haemolytic anaemia and myelodysplastic syndromes are similar to those reported by others. The results of this study stress the advantages of evaluating the erythropoietic activity of the bone marrow by means of the ITE.

[Psychogeriatrics and psychoballet]. / Psicogeriatria y psicoballet.

Third age within humanity has a very important place at world level and it is 11% of total population in our country. Because of the importance that our Ministry of Public Health gives to this determined population move us to carry on this paper, therefore, 26 psychogeriatric patients were selected at random, to who direct attention was offered in elemental ballet techniques. These patients are under the medical care required because of their mental affection, but they also attend to the occupational therapeutical area at the Psychiatric Hospital, Havana, where an adequate therapeutical treatment is given to them, from Monday to Friday at 8:00 a.m. until 10 a.m., and during the year in the performance of this activity we were able to observe a remarkable improvement in such patients, who have improved their interpersonal relationships, and doses of psychopharmaceuticals have been decreased.

[Effect of intracerebroventricular injection of histamine on the behavior of the white rat]. / Efectos de la inyección intracerebroventricular de histamina sobre el comportamiento de la rata blanca.

Previous references showed that the histamine injected peripherically produced a deterioration of the learning in experimental animals. The effects of 100 and 200 micrograms of histamine administered in the cerebral lateral ventricle, have been tested using an experimental paradigm which isolated attentional, motivational, and motor factor from the complex learned behavior. The obtained results showed to be similar to those produced by peripheric injection, and demonstrated a worsening in attentional, motivational, and motor parameters.