Biomathematical enzyme kinetics model of prebiotic autocatalytic RNA networks: degenerating parasite-specific hyperparasite catalysts confer parasite resistance and herald the birth of molecular immunity.

Catalysis and specifically autocatalysis are the quintessential building blocks of life. Yet, although autocatalytic networks are necessary, they are not sufficient for the emergence of life-like properties, such as replication and adaptation. The ultimate and potentially fatal threat faced by molecular replicators is parasitism; if the polymerase error rate exceeds a critical threshold, even the fittest molecular species will disappear.

Energy-harnessing problem solving of primordial life: Modeling the emergence of catalytic host-nested parasite life cycles.

All life forms on earth ultimately descended from a primordial population dubbed the last universal common ancestor or LUCA via Darwinian evolution. Extant living systems share two salient functional features, a metabolism extracting and transforming energy required for survival, and an evolvable, informational polymer-the genome-conferring heredity. Genome replication invariably generates essential and ubiquitous genetic parasites.

Upper respiratory tract disease in captive orangutans (Pongo sp.): prevalence in 20 European zoos and predisposing factors.

Background: Upper respiratory tract disease (URTD) is a significant cause of morbidity in captive orangutans (Pongo abelii, Pongo pygmaeus), and the pathogenesis is often unknown.

Methods:  The prevalence of respiratory disease in captive European orangutans (201 animals; 20 zoos) and possible predisposing factors were investigated.

Results: Bornean orangutans (P.

[Accidental fall and word finding problems in heart valve disease].

Abscesses of the spleen are rare and, if untreated, lead to death. The usual mode of development is by hematogenous spread of infection. Treatment options are splenectomy, percutaneous drainage and in selected cases an antibiotic therapy.

[Acute giant cell hepatitis in a 17-year old man].

Abuse of ecstasy is the second most frequent cause of acute liver failure in young adults less than 25 years of age. Typically, the disease has an acute onset and runs a severe course with jaundice, coagulopathy and a tendency to hypoglycemia. Transplantation of the liver may be required.