Biochemical characterization and molecular cloning of a plasminogen activator proteinase (LV-PA) from bushmaster snake venom.

The protein (LV-PA) from bushmaster (Lachesis muta muta) venom is a serine proteinase which specifically activates the inactive proenzyme plasminogen. LV-PA is a single chain glycoprotein with an apparent molecular mass of 33 kDa that fell to 28 kDa after treatment with N-Glycosidase F (PNGase F). Approximately 93% of its protein sequence was determined by automated Edman degradation of various fragments derived from a digestion with trypsin.

Interaction of a plasminogen activator proteinase, LV-PA with human alpha2-macroglobulin.

Lachesis venom plasminogen activator (LV-PA) is a 33-kDa serine proteinase isolated from bushmaster (Lachesis muta muta) snake venom, which activates the fibrinolytic system in vitro. This study has examined the effect of the plasma proteinase inhibitor alpha2-macroglobulin (alpha2-M) towards LV-PA and compares it with the effect on tissue type plasminogen activator (t-PA). The proteolytic activity of LV-PA alone or previously incubated with human plasminogen (Plg) on the large molecular mass protein substrates, dimethylcasein (DMC) and fibrinogen (Fg) was completely inhibited by human alpha2-M.

Isolation and biochemical characterization of a fibrinolytic proteinase from Bothrops leucurus (white-tailed jararaca) snake venom.

In investigations aimed at characterizing snake venom clot-dissolving enzymes, we have purified a fibrinolytic proteinase from the venom of Bothrops leucurus (white-tailed jararaca). The proteinase was purified to homogeneity by a combination of molecular sieve chromatography on Sephacryl S-200 and ion-exchange chromatography on CM Sepharose. The enzyme called leucurolysin-a (leuc-a), is a 23 kDa metalloendopeptidase since it is inhibited by EDTA.

The efficacy of influenza vaccine in elderly persons. A meta-analysis and review of the literature.

Objective: To quantify the protective efficacy of influenza vaccine in elderly persons.

Data Sources: A MEDLINE search was done using the index terms influenza vaccine, vaccine efficacy, elderly, mortality, hospitalized, and pneumonia. Appropriate references in the initially selected articles were also reviewed.

Influenza virus vaccine: a need for emphasis.

Each year, there are more than 20,000 influenza associated deaths during influenza virus epidemics. There is an increase in hospital admission for patients with pneumonia, exacerbation of chronic obstructive pulmonary disease, croup, and congestive heart failure, and an increase in school and industrial absenteeism. Yet only 30% of the high-risk target population receives influenza vaccination annually.