A specific, sensitive, and reproducible radioimmunoassay for human plasma thromboplastin antecedent (PTA, factor Xl) has been developed with purified PTA and monospecific rabbit antiserum. Precise measurements of PTA antigen were possible for concentrations as low as 0.3% of that in normal pooled plasma. Normal plasma contained approximately 6 zg PTA/mI. A good correlation (correlation coeffici...

The expression of the pre-T cell receptor alpha (pTa) gene occurs exclusively in immature T lymphocytes and is regulated by poorly defined mechanisms. We have analyzed the role of the upstream enhancer in pTa expression using conventional and bacterial artificial chromosome (BAC) reporter transgenes. The deletion of the enhancer completely abolished the expression of pTa BAC reporter in transge...

A persistent puzzle in our understanding of hemostasis has been the absence of hemorrhagic symptoms in the majority of patients with Hageman trait, the hereditary deficiency of Hageman factor (factor XII). One proposed hypothesis is that alternative mechanisms exist in blood through which plasma thromboplastin antecedent (PTA, factor XI) can become active in the absence of Hageman factor. In or...

OBJECTIVE To evaluate the feasibility, technical effectiveness and limb salvage potential of percutaneous transluminal angioplasty (PTA), particularly infrapopliteal, in diabetic subjects with ischaemic foot ulcer. DESIGN Intervention study with PTA in consecutive series. SETTING Six Diabetology Foot Centres and one Cardiovascular Catheterization Laboratory in Italy. SUBJECTS Two hundred ...

The effect of the polyclonal T-cell activators (PTA) Con A and PHA on the specific immune response to sheep red blood cells (SRC) was studied. Addition of PTA either enhanced or suppressed the anti-SRC response, and two variables were found to affect the results: time of addition of the PTA and the strength of the response in control cultures not given PTA. If the response was high, even subopt...

A pivotal-differential evolution pattern is when two allopolyploids share a common genome, which is called pivotal, and differ with respect to the other genome or genomes, called differential. This feature induces the intergenomic recombination between chromosomes of differential genomes, which can lead to speciation. Our study is a cytomolecular insight into this mechanism which was adapted fo...

The structure of the title compound, [Cu(PTA)(4)]Cl·6H(2)O (PTA is 1,3,5-triaza-7-phosphaadamantane, C(6)H(12)N(3)P), is composed of discrete monomeric [Cu(PTA)(4)](+) cations, chloride anions and uncoordinated water mol-ecules. The Cu(I) atom exhibits tetra-hedral coordination geometry, involving four symmetry-equivalent P-bound PTA ligands. The structure is extended to a regular three-dimensi...

Records of coma and post-traumatic amnesia (PTA) were collected for a group of 38 patients with closed head injury. The results confirmed earlier studies indicating that patients may have short or negligible coma but report prolonged PTA. Comparison of eight patients with prolonged PTA (> 7 days) and short coma (< 6 hours) with the rest of the group on MRI in the acute stage showed that these p...

The efficacy of percutaneous transluminal angioplasty (PTA) is usually expressed as the angiographic result. Access flow (Qa) measurements offer a means to quantify the functional effects. This study was performed to evaluate the short-term functional and angiographic effects of PTA and to determine the longevity of the functional effects during the follow-up period. Patients with an arterioven...

BACKGROUND The previous studies have demonstrated that the polysaccharide isolated from Tarphochlamys affinis (PTA) exhibits anti-tumor effect on S180 tumor-bearing mice and protective effects against hepatic injury. METHODS In this study, we investigated the anti-tumor activity and possible underlying mechanism of PTA on liver cancer using a murine H22 hepatocarcinoma model. RESULTS PTA wa...