No abstract

Hepatic encephalopathy (HE) is a neuropsychiatric hepatic‑induced syndrome in which several factors are involved in promoting brain perturbations, with ammonia being the primary factor. Motor impairment, incoordination, and gut dysbiosis are some of the well‑known symptoms of HE. Nevertheless, the link between the direct effect of hyperammonemia and associated gut dysbiosis in the pathogenesis of HE is not well established. Thus, this work aimed to assess motor function in hyperammonemia and gut dysbiosis in mice. Twenty‑eight Swiss mice were distributed into three groups: two‑week and four‑week hyperammonemia groups were fed with an ammonia‑rich diet (20% w/w), and the control group was pair‑fed with a standard diet. Motor performance in the three groups was measured through a battery of motor tests, namely the rotarod, parallel bars, beam walk, and static bars. Microbial analysis was then carried out on the intestine of the studied mice. The result showed motor impairments in both hyperammonemia groups. Qualitative and quantitative microbiological analysis revealed decreased bacterial load, diversity, and ratios of both aerobic and facultative anaerobic bacteria, following two and four weeks of ammonia supplementation. Moreover, the Shannon diversity index revealed a time‑dependent cutback of gut bacterial diversity in a treatment‑time‑dependent manner, with the presence of only Enterobacteriaceae, Streptococcaceae, and Enterococcaceaeat at four weeks. The data showed that ammonia‑induced motor coordination deficits may develop through direct and indirect pathways acting on the gut‑brain axis.

No abstract

No abstract

Coronaviruses are a large family of viruses that usually cause mild to moderate upper-respiratory tract illnesses, like the common cold. They were named according to the shape of glycoprotein spikes present on the viral surface and resembling to the solar corona. The first coronaviruses identified in human were HCoV 229E and the HCoV OC43, known also as β-coronavirus. This virus family has become increasingly important and received more attention within scientific community in the past two decades because of three new viruses that can cause serious, even fatal, disease. These are SARS coronavirus (SARS-CoV), which emerged in November 2002 and caused severe acute respiratory syndrome (SARS); Middle East respiratory syndrome (MERS) caused by the MERS coronavirus (MERS-CoV), identified in September 2012 and continues to cause sporadic and localized outbreaks. The third novel coronavirus to emerge in this century is called SARS-CoV-2. This chapter will describe the history of the coronavirus family discovery, emergence, and classification of the main coronaviruses.