الفهرس 
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Abstract
Our study included
(42) B thalassaemia major patients
which were divided into two groups splenectomized (14) and
non splenectomized (28) patients, age ranged (1-17 years).
And also (14) age matched normal healthy children, age
ranged (2-13 years), were included as control group.
The present study is a modest attempt to evaluate the
possible changes which may occur in the thalassaemic red
cell membrane
lipids (phospholipids, triglycerides and
cholesterol), ATP, ATPase and protein kinase. Moreover,
plasma and intra-corpascular Ca++ that might account for
their rapid lysis, and might have a clinical and scientific
value.
The results obtained in this studY revealed significant
decrease in red cell membrane phospholipids and
triglycerides and a non significant decrease in red cell
membrane cholesterol in both B-thalassaemia major
(splenectomized
and non splenectomized) as compared to
normal control one.
However there were a significant increase and a
significant decrease in red cell membrane phospholipids and
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triglycerides respectively in B thalassaemic non
splenectomized patients as compared to splenectomized one.
Our finding concerning the significant decrease of red
cell membrane phospholipids and triglycerides, and the non
significant decrease of red cell membrane cholesterol in B
thalassaemic patients could be explained by :
* The possible decrease of erythrocyte membrane ATP
formation, which could affect fatty acid acylation
pathway to renew native phospho-lipids.
* Decreased activity of the acylase enzyme which is
needed to prevent accumulation of deleterious
lysophospholipids within the membrane.
* Abnormalities in plasma lipids and lipoprotein
metabolism which were associated with the possible
changes in composition and fluidity of erythrocyte
membrane.
* Accelerated erythropoiesis and histiocytes of the
reticulo endothelial system may be one of the factors
which may lead to low plasma cholesterol levels.
* And, or,
activity
the possibility of decreased synthesis and
of acylase enzyme due to disturbance in
nucleotides precursors and ATP production caused by the
disturbed metabolism in the thalassaemic red cell
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membrane, together with the formation of abnormal
active sites of acylase enzyme on the cell membrane due
to the abnormal precipitation and disorganization of ~
globin chain.
All these factors, together with the possible decrease
of acylase activity on the cell membrane lysophospholipids
leading to decrease phospho-lipids and concomitant increase
in lysophospholipids with its powerful haemolytic activity.
Also in this work, we found a significant decrease in
red cell membrane ATP, ATPase and protein kinase in the
thalassaemic patients as compared to normal control one, a
findings could be explained by :
* Impaired 5 phosphoribosy -1- pyrophosphate (PRPPl
synthesis which is a precursor for adenine nucleotides.
* Decreased ATP synthesis due to defective metabolism in
the glycolytic pathway.
* Defective in Ca++. haemostasis and its absorption may
lead to decrease activity of ATPase and protein kinase.
* And or, the decrease of red cell membrane ATP synthesis
may lead to the decrease of ATPase and protein kinase
which is needed for their synthesis.
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As regards plasma and intracorpascu1ar Ca++ a non
significant changes in the thalassaemic patients were found
as compared to normal control one.
Finally, from this study, we could conclude that, a
significant decrease in red cell membrane phospholipids,
triglycerides, ATP, ATPase and protein kinase in
thalassaemic patients.
Together with a non significant changes was found in
red cell membrane cholesterol, plasma and intracorpascular
Ca++ in the thalassaemic patients.
All, these finding aight be the cause of decreased
flexibility and deformability of thalassaemic red cells
leading to decrease in red cell survival and its rapid
lysis.
We recommend future studies on plasma and red cell
membrane in thalassaemic patients especially the following
parameters.
* Lipids and phospholipids fractionation especially fatty
acids.
* Proteins and lipoproteins fractionation.
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* Evaluation of the acylase enzyme activity.
* Study of Ca++ haemostasis.