Although the excellent review on the contact system by Colman and Schmaier1 that appeared recently in Blood examines the subject in great detail, there are some points that deserve further discussion. A major item in that review is the novel observation, described recently in Blood,2 that prekallikrein (PK) becomes activated when it is bound to high molecular weight kininogen (HK) on endothelia...

RATIONALE Patients with obstructive sleep apnea (OSA) adapt to the anatomical vulnerability of their upper airway by generating increased activity in upper airway-dilating muscles during wakefulness. Norepinephrine (NE) and serotonin (5-HT) mediate, through α₁-adrenergic and 5-HT₂A receptors, a wake-related excitatory drive to upper airway motoneurons. In patients with OSA, this drive is necess...

Polyphosphate is an inorganic procoagulant polymer. Here we develop specific inhibitors of polyphosphate and show that this strategy confers thromboprotection in a factor XII-dependent manner. Recombinant Escherichia coli exopolyphosphatase (PPX) specifically degrades polyphosphate, while a PPX variant lacking domains 1 and 2 (PPX_Δ12) binds to the polymer without degrading it. Both PPX and PPX...

In this paper, we present a new class of public key cryptosystem based on Reed-Solomon codes, a member of the code based PKC(CBPKC), referred to as K(XII)SE(1)PKC. We show that K(XII)SE(1)PKC can be secure against the various attacks. Particularly we present a member of K(XII)SE(1)PKC constructed based on the Reed-Solomon code over the extension field F28 , which is extensively used in the pres...

Activated mast cells trigger edema in allergic and inflammatory disease. We report a paracrine mechanism by which mast cell-released heparin increases vascular permeability in vivo. Heparin activated the protease factor XII, which initiates bradykinin formation in plasma. Targeting factor XII or kinin B2 receptors abolished heparin-triggered leukocyte-endothelium adhesion and interfered with a ...

Differentiated osteoblasts are polarized in regions of bone deposition, demonstrate extensive cell interaction and communication, and are responsible for bone formation and quality. Type XII collagen is a fibril-associated collagen with interrupted triple helices and has been implicated in the osteoblast response to mechanical forces. Type XII collagen is expressed by osteoblasts and localizes ...

Neonatal Mortality Rate (NMR) can be defined as the number of newborn deaths’ aged 0 to 28 days. The most significant factor influenced NMR is low birth weight of newborn babies approximately 48%, followed by asphyxia 37% and sepsis 32.5%. This paper deploys a Burr XII distribution to model the Non-Normal Neonatal Weight data. The parameters of the fitted Burr XII distribution are estimated usi...

In situ Raman spectra of transformations of H2O as functions of pressure and temperature have been measured starting from high-density amorphous ice (HDA). Changes above Tx, the crystallization temperature of HDA, were observed. The spectra provide evidence for an abrupt, first-order-like, structural change that appears to be distinct from those associated with the transformation between low-de...

Structural studies on a congenital abnormal coagulation factor XII (Hageman factor), factor XII Washington D.C., have been performed to identify the defect responsible for its lack of procoagulant activity. Amino acid sequence analysis of a tryptic peptide isolated from the abnormal factor XII indicated that Cys-571 (equivalent to Cys-220 in the chymotrypsin numbering system) had been replaced ...