what is the exact problem in PNH?

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what is the exact problem in PNH?

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4 Posts

tess
Forum Guru

Topics: 131
Posts: 368

06/23/04 - 02:45 PM

What is the exact problem in PNH, defect in CD59, or PIG-A (Phosphatidyl inositol glycan A), or decay accelerating factor (DAF)?

Confused! Please clearify! :shock:

prep4usmle
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06/23/04 - 04:31 PM

The exact defect in Paroxysmal Nocturnal Hemoglobinuria (PNA) is a non-inherited (aquired) mutation on the gene responsiblle for the synhtesis of the enzyme PIG-A (phosphatidylinositol glycan class A) in the X chromosome of some stem cells.

This PIG-A is involved in the synthesis of the glycosyl-phosphatidylinositol (GPI) anchor which binds some complement-regulating surface proteins on all hematopoietic cell membranes (like DAF and CD59) and protect the cells from complement atack.

no enzyme > no anchor > no protection > hemolysis

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tess
Forum Guru

Topics: 131
Posts: 368

06/24/04 - 06:47 AM

Thank you very much! smiling face

BellKicker
Forum Junior

Topics: 3
Posts: 49

06/24/04 - 04:03 PM

"prep4usmle" wrote:
The exact defect in Paroxysmal Nocturnal Hemoglobinuria (PNA) is a non-inherited (aquired) mutation on the gene responsiblle for the synhtesis of the enzyme PIG-A (phosphatidylinositol glycan class A) in the X chromosome of some stem cells.

This PIG-A is involved in the synthesis of the glycosyl-phosphatidylinositol (GPI) anchor which binds some complement-regulating surface proteins on all hematopoietic cell membranes (like DAF and CD59) and protect the cells from complement atack.

no enzyme > no anchor > no protection > hemolysis

I understood maybe 50% of those words........

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