Intravascular fragment

Whereas IgG is the most abundant antibody in the hyperimmunized host, in the newly immunized animal, IgM is the first humoral antibody detectable. The primary antibody formation proceeds in several major stages. Injected immunogen first reaches equilibrium between extra-and intravascular spaces, then undergoes catabolism resulting in smaller fragments, and finally is eliminated from the intravascular spaces by the newly formed antibodies. The period from the introduction of an immunogen until the first appearance of humoral IgM antibodies is called the latent period and may last approximately one week. Within two weeks, or in response to a second injection, IgG class antibodies usually predominate. Like all proteins, antibodies are subject to catabolism. Whereas antibodies of class IgM have a relatively short half-life of only four to six days, IgG antibodies have a mean survival of approximately three weeks. Unless repeated booster... 

Thrombotic thrombocytopenic purpura is a rare acute or subacute disease in adults, rather similar to the hemolytic uremic syndrome in children, in which there is systemic malaise, fever, skin purpura, renal failure, hematuria and proteinuria. Hemorrhagic infarcts caused by platelet microthrombi occur in many organs in the brain they may cause stroke-like episodes (Matijevic and Wu 2006) although more commonly there is global encephalopathy. The blood film shows thrombocytopenia, hemolytic anemia and fragmented red cells. The differential diagnosis includes infective endocarditis, idiopathic thrombocytopenia, heparin-induced thrombocytopenia with thrombosis, systemic lupus erythematosus, non-bacterial thrombotic endocarditis and disseminated intravascular coagulation. 

Intravascular destruction of sickle cells may occur at an accelerated rate. The stresses of circulation, and repetitive sickle-unsickle cycles are likely to lead to cell fragmentation. Damage to the cell membrane promotes cell recognition by macrophages. Rigid ISCs are easily trapped, resulting in short circulatory survival and chronic hemolysis. The typical sickled cell survives for about 10 to 20 days, while life spans of normal RBCs are 100 to 120 days. 

A recent report by Parsons et a/." presented evidence for simultaneous elevation of complement fragments and measurable levels of endotoxin in plasma from patients with ARDS. Because complement activation by toxins and by other mechanisms" is thought to cause neutrophil and platelet activation" and subsequent generation of toxic oxygen species and eico-sanoids various strategies known to activate intravascular complement have been used to examine the role of eicosanoids in lung injury . To... 

The transfemoral approach is adopted in many centers as a primary approach when free-floating leads are involved and as an alternative approach in case of failed primary approach through the implant vein [23, 43-45]. Some techniques using the transfemoral approach allow grasping and removal of exposed or intravascular leads, fragments of... 

The intravascular position of the leads or lead fragments is relatively common in patients undergoing transvenous lead extraction. Lead to remove can be free floating either as (1) the result of lead fracture in its intravascular course or (2) the result of an intervention. 

Curry JA. Recovery of a detached intravascular catheter or guidewire fragments a proposed method. Am J Radiol 1969 105 894. 

The haemolytic uraemic syndromes (HUSs) are a heterogeneous group of similar entities with variable expression and severity. Renovascular endothelial cell injury is central to the pathogenesis, leading to platelet activation and intravascular coagulation, haemolytic anaemia with fragmented erythrocytes, thrombocytopenia, and renal failure. 

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