Blood clotting, which involves the interplay of cellular elements called platelets and a number of clotting factors
that bear common and Roman numeral names, plays an important role in maintaining the integrity of blood vessels.
The addition of small amounts of the patient's plasma to normal plasma (containing clotting factor
activities of about 100 IU/dL, thereby balancing potential clotting factor
deficiencies) produced severe and nonlinear aPTT prolongation (see Fig.
7) These clotting factors
and fibrinogen are critical for normal hemostasis.
Some civilian surgical teams have also recommended increasing the focus on early and aggressive replacement of clotting factors
in the resuscitation process following massive hemorrhage.
In a series of eight consecutive hemophiliac patients with chronic hepatitis C virus (HCV) infection treated at one center with a combination of ribavirin and interferon alfa-2b, five patients had moderate or severe hemophilia that required significantly less use of clotting factors
on average during each month of treatment than in the 6 months prior to combination therapy (1,605 U/mo vs.
An adult with severe hemophilia typically will experience eight to 10 bleeds per month and self-administer 1,500 to 4,000 units of clotting factor
Patients with factor IX levels that are 5% or more of normal typically require infusion of clotting factor
only after an accident or for surgery.
The addition of a human cell is expected to enable the clones, when they grow up and reproduce, to provide milk containing a human clotting factor
that can be used to heal people with haemophilia, Wong said.
Cell Genesys is pursuing gene therapies for hemophilia A and hemophilia B -- genetic deficiencies in factor VIII and factor IX clotting factor
This means their blood lacks an essential clotting factor
The incidence of von Willebrand disease - which is similar to hemophilia but different in that the deficient clotting factor
does not always remain at the same level - is not known.
Recent evolution of clotting factor
concentrates for hemophilia A and B.