Vascular mineralization in the brain of horses
JOURNAL OF VETERINARY DIAGNOSTIC INVESTIGATION
Authors: Martinez, Jorge; Montgomery, Donald L.; Uzal, Francisco A.
Abstract
Vascular mineralization (siderocalcinosis) in the brain of horses has been usually assumed to be an incidental age-related finding with no clinic significance. In the present study, eight 15-32-year-old horses of different breeds with cerebral siderocalcinosis were studied. Four of these horses had acute and severe central nervous system clinical signs of unknown etiology, 2 horses had neurological signs of known cause, and 2 horses did not have neurological signs. Gross examination of the brains in 4 animals revealed symmetrical foci of malacia in the cerebellar white matter. Histologically, moderate to severe mineralization of blood vessels and parenchyma were observed in all 8 horses, occasionally associated with necrosis of the adjacent tissue. Some horses were tested by virus isolation, polymerase chain reaction, immunohistochemistry, and serology to investigate Rabies virus; West Nile virus; Equid herpesvirus 1 and 4; Eastern, Western, Venezuelan, and Saint Louis encephalitis virus; and Sarcocystis neurona infection. These tests were negative in all samples analyzed. Brain cholinesterase activity and heavy metal screening were also unremarkable. The significance of the vascular and parenchymal mineralization in the brains of some of these horses remains undetermined. However, the severity of the lesions observed in the brains of some of the animals in the present study, coupled with the negative results for other common causes of neurological disease in horses, suggests a possible relationship between siderocalcinosis and the clinical signs observed.
Climate Change Influences on the Global Potential Distribution of the Mosquito Culex quinquefasciatus, Vector of West Nile Virus and Lymphatic Filariasis
PLOS ONE
Authors: Samy, Abdallah M.; Elaagip, Arwa H.; Kenawy, Mohamed A.; Ayres, Constancia F. J.; Peterson, A. Townsend; Soliman, Doaa E.
Abstract
Rapid emergence of most vector-borne diseases (VBDs) may be associated with range expansion of vector populations. Culex quinquefasciatus Say 1823 is a potential vector of West Nile virus, Saint Louis encephalitis virus, and lymphatic filariasis. We estimated the potential distribution of Cx. quinquefasciatus under both current and future climate conditions. The present potential distribution of Cx. quinquefasciatus showed high suitability across low-latitude parts of the world, reflecting the current distribution of the species. Suitable conditions were identified also in narrow zones of North Africa and Western Europe. Model transfers to future conditions showed a potential distribution similar to that under present-day conditions, although with higher suitability in southern Australia. Highest stability with changing climate was between 30 degrees S and 30 degrees N. The areas present high agreement among diverse climate models as regards distributional potential in the future, but differed in anticipating potential for distribution in North and Central Africa, southern Asia, central USA, and southeastern Europe. Highest disparity in model predictions across representative concentration pathways (RCPs) was in Saudi Arabia and Europe. The model predictions allow anticipation of changing distributional potential of the species in coming decades.