A new approach to neonatal medical management that could transform the prevention of retinopathy of prematurity: Theoretical considerations.

Retinopathy of prematurity (ROP) is a disease of the immature retina and is the leading global cause of blindness in children. Two postnatal phases of the disease are distinguished, the first phase is thought to be caused by hyperoxia. One of the most relevant ROP risk factor in routine clinical practice is blood transfusion which leads to the introduction into the neonatal circulation of 'non-physiological' adult haemoglobin (HbA) rather than the physiological foetal haemoglobin (HbF). Due to their different affinities for oxygen, HbA will release into retina more oxygen than HbF. It can be expected that this much greater influx of oxygen from HbA may be sensed by the relevant retinal receptors as hyperoxia. Based on the above considerations, I propose that the introduction of non-physiological HbA from adult donors during blood transfusion for anaemia is of key importance in the development and progression of ROP. This hypothesis predicts that there is an HbA limit, beyond which the sequence of events described in the pathogenesis of ROP is triggered. To prevent ROP, I propose launching a new medical field: neonatal transfusion medicine. This system would involve the collection and preparation of umbilical cord blood from the placenta of healthy newborns (containing almost 100% HbF), which would then be administered to premature newborns (who are at risk of ROP) instead of adult blood.

Electrical potentials between stent-grafts made from different metals induce negligible corrosion.

OBJECTIVE: Evaluation of the risk of galvanic corrosion in various stent-grafts in current practice, when devices with unmatched alloy compositions are deployed together. METHOD: Five nitinol (NT) and two steel (SS) stent-grafts produced by different companies were used in different combinations to create 21 samples (NT:NT, n = 10; NT:SS, n = 10; SS:SS, n = 1). Electric potential was measured between the metal couplings after immersion in 0.9% NaCl at a temperature of 37 °C. Subsequently, the same samples were incubated for 24 months in 0.9% NaCl at 37-39 °C under hermetic conditions and examined under a scanning electron microscope in order to search for any evidence of corrosion. RESULTS: Electric potentials between different metals alloys were found (means: NT:SS, 181 µV; NT:NT, 101 µV; SS:SS, 160 µV). The mean electrical potential between stainless steel and nitinol samples was significantly higher than between NT:NT couplings (p < .001). During the final scanning electron microscope examination, only one spot of pitting corrosion (>10 µm) on a nitinol surface was found (associated with previous mechanical damage) in an NT:SS sample after 24 months of incubation in vitro and no sign of mechanical failure of the wires was found. CONCLUSION: Direct contact between the stainless steel and the nitinol alloys does indeed create electrical potential but with a minimal risk of galvanic corrosion. No evidence was found for significant galvanic corrosion when two endovascular implants (stent-grafts) made from different metal composition were used in the same procedure.

Childhood leukaemia relapse risk factors. A rough sets approach.

A rough sets approach was applied to a data set consisting of clinical and laboratory examinations (condition attributes) of children with acute lymphoblastic leukaemia to generate a set of rules for the prediction of disease relapse (conclusion attributes). The information system is presented as a table composed of 69 rows corresponding to the patients and 16 columns corresponding to the attributes. Using manipulation based on rough set theory the information system is reduced to get a subset of a minimum number of attributes ensuring an acceptable quality of classification. Then the conclusion algorithm derived from the reduced system is presented as a conclusion table. The relationship between condition and conclusion attributes is being shown. The research leads to the conclusion that intensive, high dose central nervous system prophylactic irradiation seems to be a better prevention against CNS relapse. Rough set theory is a useful and still complementary tool of medical (biological) data analysis.

[Evaluation of rearrangement of immunoglobulin genes and T cell receptors in determining low numbers of leukemic in children with acute lymphoblastic leukemia]. / Ocena przemieszczen genów immunoglobulinowych i receptorów limfocytów T w wykrywaniu sladowej liczby komórek nowotworowych u dzieci z ostra bialaczka limfoblastyczna.

The samples from blood and/or bone marrow were analysed in 7 children at the time of initial diagnosis or relapse and in 9 children with clinical and hematologic remission of ALL. Molecular genetic methods were more sensitive than morphologic ones in leukemic cells detection: 5 children in remission of ALL demonstrated gene rearrangements. Clinical significance of the presence of low numbers of leukemic cells in remissions is still unknown.

CHOP treatment of childhood acute myelogenous leukemia with monocytic differentiation: a report on five cases.

Five children with M4 or M5 acute myelogenous leukemia (AML) not responding to previous treatment or in relapse were treated with a four-drug protocol consisting of cyclophosphamide, adriamycin, vincristine, prednisone, and CNS prophylaxis. There were two treatment failures; the remaining three patients have achieved complete remission, lasting 18+, 13+, and 12+ months respectively. Further follow-up is to be performed.