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The new coronavirus (COVID‐19) was first reported in Wuhan in China, on 31 December 2019. COVID‐19 is a new virus from the family of coronaviruses that can cause symptoms ranging from a simple cold to pneumonia. The virus is thought to bind to the angiotensin‐converting enzyme 2, as a well‐known mechanism to enter the cell. It then transfers its DNA to the host in which the virus replicates the DNA. The viral infection leads to severe lack of oxygen, lung oxidative stress because of reactive oxygen species generation, and overactivation of the immune system by activating immune mediators. The purpose of this review is to elaborate on the more precise mechanism(s) to manage the treatment of the disease. Regarding the mechanisms of the virus action, the suggested pharmacological and nutritional regimens have been described.

The Coronaviridae family comprises large enveloped single-stranded RNA viruses. The known human-infecting coronaviruses; severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), novel SARS-CoV-2, human coronavirus (HCoV)-NL63, HCoV-229E, HCoV-OC43 and HKU1 cause mild to severe respiratory infections. The viral diseases induced by mammalian and avian viruses from Coronaviridae family pose significant economic and public health burdens. Due to increasing reports of viral resistance, co-infections and the emergence of viral epidemics such as COVID-19, available antiviral drugs show low or no efficacy, and the production of new treatments or vaccines are also challenging. Therefore, demand for the development of novel antivirals has considerably increased. In recent years, antiviral peptides have generated increasing interest as they are from natural and computational sources, are highly specific and effective, and possess the broad-spectrum activity with minimum side effects. Here, we have made an effort to compile and review the antiviral peptides with activity against Coronaviridae family viruses. They were divided into different categories according to their action mechanisms, including binding/attachment inhibitors, fusion and entry inhibitors, viral enzyme inhibitors, replication inhibitors and the peptides with direct and indirect effects on the viruses. Reported studies suggest optimism with regard to the design and production of therapeutically promising antiviral drugs. This review aims to summarize data relating to antiviral peptides particularly with respect to their applicability for development as novel treatments.

Deficits in executive functions have been hypothesized and documented for children with severe mathematics anxiety (MA) or developmental dyscalculia, but the role of inhibition-related processes has not been specifically explored. The main aim of the present study was to shed further light on the specificity of these profiles in children in terms of working memory (WM) and the inhibitory functions involved. Four groups of children between 8 and 10 years old were selected: one group with developmental dyscalculia (DD) and no MA, one with severe MA and developmental dyscalculia (MA-DD), one with severe MA and no DD (MA), and one with typical development (TD). All children were presented with tasks measuring two inhibition-related functions, that is, proactive interference and prepotent response, and a WM task. The results showed that children with severe MA (but no DD) were specifically impaired in the proactive interference task, while children with DD (with or without MA) failed in the WM task. Our findings point to the importance of distinguishing the cognitive processes underlying these profiles.

The eyes of zebra finches are placed laterally, the foveae are looking into different directions. It is unlikely that the birds are able to process different images from both eyes simultaneously. A neural mechanism might therefore be necessary to guide the birds' attention to one of the two eyes and to reduce the processing of information of the other. Previous studies revealed that information from the ipsilateral eye is indeed suppressed on its way to the telencephalon by the activity of the contralateral eye. It has been suggested that two nuclei of the tecto-thalamic tract, nucleus subpraetectalis and nucleus interstitio praetecto subpraetectalis, are a central part of such a suppressive mechanism. Using electrophysiological recordings, we investigated the influence of these two nuclei and nucleus rotundus on the processing of binocular visual information by treating the nuclei with picrotoxin or electrolytic lesions. Deactivation of inhibitory neurons within SP/IPS leads to a significant increase of the ectostriatal responses to ipsilateral and bilateral stimulation, the responses to contralateral stimulation remain unaffected. Lesioning SP/IPS does not alter the responses to visual stimuli. Treatment of nucleus rotundus with picrotoxin increases contralaterally and bilaterally, but not ipsilaterally evoked responses. A wiring diagram is presented which interprets these findings.

Motor directional tuning (Georgopoulos et al., 1982) has been found in every brain area in which it has been sought for during the past 30-odd years. It is typically broad, with widely distributed preferred directions and a population signal that predicts accurately the direction of an upcoming reaching movement or isometric force pulse (Georgopoulos et al., 1992). What is the basis for such ubiquitous directional tuning? How does the tuning come about? What are the implications of directional tuning for understanding the brain mechanisms of movement in space? This review addresses these questions in the light of accumulated knowledge in various sub-fields of neuroscience and motor behavior. It is argued (a) that direction in space encompasses many aspects, from vision to muscles, (b) that there is a directional congruence among the central representations of these distributed directions arising from rough but orderly topographic connectivities among brain areas, (c) that broad directional tuning is the result of broad excitation limited by recurrent and non-recurrent (i.e. direct) inhibition within the preferred direction loci in brain areas, and (d) that the width of the directional tuning curve, modulated by local inhibitory mechanisms, is a parameter that determines the accuracy of the directional command.

The control of routine action is a complex process subject both to minor lapses in normals and to more severe breakdown following certain forms of neurological damage. A number of recent empirical studies (e.g. Humphreys & Ford, 1998; Schwartz et al., 1991, 1995, 1998) have examined the details of breakdown in certain classes of patient, and attempted to relate the findings to existing psychological theory. This paper complements those studies by presenting a computational model of the selection of routine actions based on competitive activation within a hierarchically organised network of action schemas (cf. Norman & Shallice, 1980, 1986). Simulations are reported which demonstrate that the model is capable of organised sequential action selection in a complex naturalistic domain. It is further demonstrated that, after lesioning, the model exhibits behaviour qualitatively equivalent to that observed by Schwartz et al., in their action disorganisation syndrome patients.