7 research outputs found
Progression of Pathogenic Events in Cynomolgus Macaques Infected with Variola Virus
Smallpox, caused by variola virus (VARV), is a devastating human disease that affected millions worldwide until the virus was eradicated in the 1970 s. Subsequent cessation of vaccination has resulted in an immunologically naive human population that would be at risk should VARV be used as an agent of bioterrorism. The development of antivirals and improved vaccines to counter this threat would be facilitated by the development of animal models using authentic VARV. Towards this end, cynomolgus macaques were identified as adequate hosts for VARV, developing ordinary or hemorrhagic smallpox in a dose-dependent fashion. To further refine this model, we performed a serial sampling study on macaques exposed to doses of VARV strain Harper calibrated to induce ordinary or hemorrhagic disease. Several key differences were noted between these models. In the ordinary smallpox model, lymphoid and myeloid hyperplasias were consistently found whereas lymphocytolysis and hematopoietic necrosis developed in hemorrhagic smallpox. Viral antigen accumulation, as assessed immunohistochemically, was mild and transient in the ordinary smallpox model. In contrast, in the hemorrhagic model antigen distribution was widespread and included tissues and cells not involved in the ordinary model. Hemorrhagic smallpox developed only in the presence of secondary bacterial infections – an observation also commonly noted in historical reports of human smallpox. Together, our results support the macaque model as an excellent surrogate for human smallpox in terms of disease onset, acute disease course, and gross and histopathological lesions
Language and Student Performance in Junior Secondary Science Examinations: The Case of Second Language Learners in Botswana
Religious Pluralism and Civic Rights in a 'Muslim Nation': An Analysis of Prophet Muhammad's Covenants with Christians
Islamic economics: a survey of the literature
A central thesis of this paper is that social science is the study of human experience, and hence is strongly conditioned by history. Modern Western political, economic and social structures have emerged as a consequence of the repudiation of religion associated with the Enlightenment and are based on secular principles. Many of these are inimical to Islamic principles, and cannot be adapted to an Islamic society. Muslim societies achieved freedom from colonial rule in the first half of the twentieth century and have sought to construct institutions in conformity with Islam. The development of Islamic economics is part of this process of transition away from Western colonial institutions. This paper is a survey of the literature on Islamic economics, which focuses on the contrasts between Western economic theories and Islamic approaches to the organization of economic affairs