Abstract:In vitro studies have shown that human myeloid leukemia cell lines: HL60 and NB4 can be stimulated to differentiation by various agents, for example, all-trans retinoic acid (ATRA) and phorbol 12-myristate 13-acetate (PMA). The purpose of this study was to investigate whether differentiation of HL60 and NB4 leukemia cell lines induced by ATRA and PMA alters their drug sensitivity. The differentiation along the neutrophil lineage (upon stimulation with ATRA) and along the monocyte/macrophage lineage (upon stimulation with PMA) was proved by decreased proliferative potential of cells, changes in their morphology, increased ability for NBT reduction and increased expression of CD11b and CD14 cell surface markers. The effect of drugs: cytosine arabinoside, daunorubicin, mitoxantrone and etoposide was examined by Alamar Blue test (proliferation and survival rates), as well as by evaluation of cell smears stained with Hoechst 33342 (apoptotic index). Differentiation resulted in the change of drug sensitivity in both cell lines: the differentiation along the neutrophil pathway (after stimulation with ATRA) increased sensitivity to cytosine arabinoside and mitoxantrone but decreased sensitivity to etoposide; the differentiation along the monocyte/macrophage pathway (induced by PMA) resulted in the decreased sensitivity of both cell lines to all drugs tested. In conclusion, we have shown that ATRA-and PMA-mediated differentiation of HL60 and NB4 cell lines results in the changes of their drug sensitivity. Our data may provide a contribution to a strategy aimed at a rational combination of differentiating agents and conventional anticancer drugs.
A new monoclonal antibody prepared against a fragment of Ki-67 antigen MIB, from Dianova, was applied for investigation of malignant melanomas of facial skin (25 cases) and the oral cavity (25 cases), which were routinely embedded in paraffin. The values of the Ki-67 index (expressed as a percentage of positive nuclei) were correlated with TNM characteristics of tumors and patient survival. Significant correlation was found between the Ki-67 index and the level of lymph node involvement (N value), the presence of distant metastases and the time of patient survival. A positive relationship between the Ki-67 value and tumor size was also observed although it lacked statistical significance.
The subject of the presented work was an attempt at optimization of the methods used for verification of the candidates for medical voluntary workers in a hospice and decreasing the danger of a negative influence of an incompetent volunteer on a person in a terminal stage of a disease and his or her relatives. The study was carried out in St. Lazarus Hospice in Krakow, Poland, and included 154 adult participants in four consecutive editions of “A course for volunteers – a guardian of the sick” organized by the hospice. In order to improve the recruitment of these workers, the hitherto methods of selection (an interview with the coordinator of volunteering and no less than 50% of attendance in classes of a preparatory course for volunteers”) were expanded by additional instruments—the tests whose usefulness was examined in practice. Knowledge of candidates was tested with the use of a written examination which consisted of four open questions and an MCQ test comprising 31 questions. Practical abilities were checked by the Objective Structured Clinical Examination (OSCE). A reference point for the results of these tests was a hidden standardized long-term observation carried out during the subsequent work of the volunteers in the stationary ward in the hospice using the Amsterdam Attitude and Communication Scale (AACS). Among the tests used, the greatest value (confirmed by a quantitative and qualitative analysis) in predicting how a given person would cope with practical tasks and in contact with the sick and their relatives had a practical test of the OSCE type.
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