Serological surveillance for Tahyna virus (California encephalitis orthobunyavirus, Peribunyaviridae) neutralizing antibodies in wild ungulates in Austria, Hungary and Romania.

A serosurvey for Tahyna virus (TAHV), a mosquito-borne California encephalitis orthobunyavirus (Peribunyaviridae) endemic to Europe, was performed to estimate the activity of TAHV on a broad geographic scale. Sera from wild boar (Sus scrofa), roe deer (Capreolus capreolus) and red deer (Cervus elaphus) were collected from Austria, Hungary and Romania. Samples were tested for neutralizing antibodies against TAHV using a virus microneutralization assay. The results demonstrate that TAHV transmission to mammals is widespread in Europe, particularly in the wild boar population where the mean rate of seroconversion is 15.2%.

Genogroup I picobirnaviruses in pigs: evidence for genetic diversity and relatedness to human strains.

Picobirnaviruses (PBVs) are small, non-enveloped viruses with a bisegmented double-stranded RNA genome. Their pathogenic potential, ecology, and evolutionary features are largely unexplored. Here, we describe the molecular analysis of porcine PBVs identified in the intestinal content of dead pigs. Six of 13 positive samples were cloned and then subjected to single-strand conformation polymorphism analysis and nucleotide sequencing. All clones belonged to genogroup I PBVs and almost all clones clustered on separate branches from human strains. A single strain shared a notably close genetic relationship with a Hungarian human PBV strain (89.9 nt and 96.4% aa identity). Genetic diversity was also observed among strains identified in mixed infections. Single point mutations and deleterious mutations within highly related strains suggested that PBVs exist as quasispecies in the swine alimentary tract. Clones with complete sequence identities originating from different animals suggested effective animal-to-animal transmission of the virus. Our findings indicate that infection with genogroup I PBVs is common in pigs.

Studies on tumor induced angiogenesis.

Methods were developed to test angiogenic response to human tumor implants and various biologic agents in the cornea of rabbits and non-human primates (Macaca arctoides). Crude PDGF preparations were found to have significant angiogenic effect. Purified, recombinant PDGF preparations were also effective inhibitors (e.g. pentoxifylline (Px) (which also were found to release PgI2 and t-PA) inhibited human tumor implant induced angiogenesis and reduced spontaneous metastases in 3 transplantable murine tumors (Furth-Columbia Wilms' tumor in Furth-Wistar rats, C-1300 neuroblastoma in A/J mice and HM-Kim mammary carcinoma in Wistar rats) but not in the NIH adenocarcinoma in Balb/c mice. Sodium diethyldithiocarbamate (DDTC), a metal complexing agent with special affinity to copper and anti-thyroid as well as, immune stimulating activity was shown to be anti-angiogenic and to potentiate the effect of Px. The anti-fibrinolytic agents epsilon amino caproic acid (EACA) and tranaxamic acid (t-AMCHA) were anti-angiogenic. DDTC and Px were synergistic from this point of view.

Studies on tumor induced angiogenesis.

Methods were developed to test the angiogenic response to human tumor implants and various biologic agents in the cornea of rabbits and non-human primates (Macaca arctoides). Human malignant melanoma tissue and crude platelet derived growth factor (PDGF) preparations had significant angiogenic effects. Purified, recombinant PDGF preparations were also effective initiators. Hemorheologic agents which also inhibit platelet aggregation [e.g. pentoxifylline (Px) (Trental) (also found to release PgI2 and tissue plasminogen activator (t-PA)] inhibited human tumor implant-induced angiogenesis. Sodium diethyldithiocarbamate (DDTC), a metal complexing agent with special affinity to copper and anti-thyroid as well as immune stimulating activity, was shown to be anti-angiogenic and to increase the effect of Px. The anti-fibrinolytic agents epsilon amino caproic acid (EACA) and tranexamic acid (t-AMCHA) were anti-angiogenic.

Choroidal metastases arising from carcinoma of the breast. Review and analysis of five cases.

Five cases of breast carcinoma metastasizing to the choroid were investigated and compared with the current literature. Choroidal metastases were found to bear an unfavorable prognostic factor (median survival of 11 months), and are related to heavy metastatic involvement even when the latter is not evident. Two patients responded to treatment, one to irradiation and one to systemic chemotherapy. The peak incidence is in perimenopasual women (mean age 48.2) which suggests that in this group of patients ocular examination may be advised for the routine followup.