Pathogenesis of Influenza A(H7N9) Virus in Aged Nonhuman Primates

The avian influenza A(H7N9) virus has caused high mortality rates in humans, especially in the elderly; however, little is known about the mechanistic basis for this. In the current study, we used nonhuman primates to evaluate the effect of aging on the pathogenicity of A(H7N9) virus. We observed that A(H7N9) virus infection of aged animals (defined as age 20–26 years) caused more severe symptoms than infection of young animals (defined as age 2–3 years). In aged animals, lung inflammation was weak and virus infection was sustained. Although cytokine and chemokine expression in the lungs of most aged animals was lower than that in the lungs of young animals, 1 aged animal showed severe symptoms and dysregulated proinflammatory cytokine and chemokine production. These results suggest that attenuated or dysregulated immune responses in aged animals are responsible for the severe symptoms observed among elderly patients infected with A(H7N9) virus.

Models of Traumatic Brain Injury in Aged Animals: A Clinical Perspective

Traumatic brain injury (TBI) is a major cause of morbidity and mortality in the United States, with advanced age being one of the major predictors of poor prognosis. To replicate the mechanisms and multifaceted complexities of human TBI and develop prospective therapeutic treatments, various TBI animal models have been developed. These models have been essential in furthering our understanding of the pathophysiology and biochemical effects on brain mechanisms following TBI. Despite these advances, translating preclinical results to clinical application, particularly in elderly individuals, continues to be challenging. This review aims to provide a clinical perspective, identifying relevant variables currently not replicated in TBI animal models, to potentially improve translation to clinical practice, especially as it applies to elderly populations. As background for this clinical perspective, we reviewed articles indexed on PubMed from 1970 to 2019 that used aged animal models for studying TBI. These studies examined end points relevant for clinical translation, such as neurocognitive effects, sensorimotor behavior, physiological mechanisms, and efficacy of neuroprotective therapies. However, compared with the higher incidence of TBI in older individuals, animal studies on the basic science of aging and TBI remain remarkably scarce. Moreover, a fundamental disconnect remains between experiments in animal models of TBI and successful translation of findings for treating the older TBI population. In this article, we aim to provide a clinical perspective on the unique attributes of TBI in older individuals and a critical appraisal of the research to date on TBI in aged animal models as well as recommendations for future studies.

PREVALENCE OF BRUCELLOSIS IN PIGS: THE FIRST REPORT IN BANGLADESH

Brucellosis, a bacterial zoonotic disease, has been reported in ruminants but still no report in pigs in Bangladesh. The aim of this study was to describe seroprevalence of brucellosis in swine in Bangladesh. Blood from a total of 105 pigs was collected from selected areas of Bangladesh. All samples were screened using Rose Bengal Test (RBT) and further confirmed by using Slow Agglutination Test (SAT). A structured questionnaire was used to collect the epidemiological data related to the animals and husbandry practices. Out of the 105 sera analyzed, 7 (6.7%) and 5 (4.8%) were found to be positive by RBT and SAT respectively. It was observed that, insignificantly higher prevalence of brucellosis based on SAT was found in female (5.6%) than male (2.9%), in aged animal (8.1%) than young (0.0%) and in pregnant animal (12.5%) than non pregnant animal (2.1%) (p>0.05). Prevalence of brucellosis was 42.9% in aborted pigs and 1.6% in non aborted pigs. The association between abortion status and prevalence of brucellosis was statistically highly significant (p<0.01). This report of prevalence of brucellosis in pigs is very important with regards to the human health and other livestock and might help Government and NGOs to design preventive measurement and establish livestock health policy.DOI: http://dx.doi.org/10.3329/bjvm.v10i1-2.15649