Follow-up of patients affected by COVID-19 has unveiled remarkable findings. Among the several sequelae caused by SARS-CoV-2 viral infection, it is particularly noteworthy that patients are prone to developing depression, anxiety, cognitive disorders, and dementia as part of the post-COVID-19 syndrome. The multisystem aspects of this disease suggest that multiple mechanisms may converge towards post-infection clinical manifestations. The literature provides mechanistic hypotheses related to changes in classical neurotransmission evoked by SARS-CoV-2 infection; nonetheless, the interaction of peripherally originated classical and non-canonic peptidergic systems may play a putative role in this neuropathology. A wealth of robust findings shows that hemoglobin-derived peptides are able to control cognition, memory, anxiety, and depression through different mechanisms. Early erythrocytic death is found during COVID-19, which would cause excess production of hemoglobin-derived peptides. Following from this premise, the present review sheds light on a possible involvement of hemoglobin-derived molecules in the COVID-19 pathophysiology by fostering neuroscientific evidence that supports the contribution of this non-canonic peptidergic pathway. This rationale may broaden knowledge beyond the currently available data, motivating further studies in the field and paving ways for novel laboratory tests and clinical approaches.

Abstract Introduction The evolving COVID-19 pandemic became a hallmark in human history, not only by changing lifestyles, but also by enriching scientific knowledge on viral infection and its consequences. Objective Although the management of cardiorespiratory changes is pivotal to a favorable prognosis during severe clinical findings, dysregulation of other systems caused by SARS-CoV-2 infection may imbalance erythrocyte dynamics, such as a bidirectional positive feedback loop pathophysiology. Method and Results Recent evidence shows that SARS-CoV-2 is capable of affecting the genetics and dynamics of erythrocytes and this coexists with a non-homeostatic function of cardiovascular, respiratory and renal systems during COVID-19. In hypothesis, SARS-CoV-2-induced systematical alterations of erythrocytes dynamics would constitute a setpoint for COVID-19-related multiple organ failure syndrome and death. Conclusion The present review covers the most frequent erythrocyte-related non-homeostatic findings during COVID-19 capable of providing mechanistic clues of SARS-CoV-2-induced infection and inspiring therapeutic-oriented scientific evidence.

RESUMO: Considerado um dos melhores detectores de odores, os cães passam por um rigoroso processo de seleção e treinamento. Baseado nas teorias da aprendizagem, utilizam-se técnicas modernas para a formação do cão respeitando suas características individuais, eficiência e o bem-estar. Uma vez que o trabalho de detecção de narcóticos seja entendido como uma grande brincadeira para o cão, isso na prática promove um alto índice de aproveitamento no serviço. O desempenho dos condutores influencia o trabalho dos cães, que bem treinados e bem conduzidos, devem trabalhar de forma confortável e precisa. Este trabalho objetiva revisar aspectos relacionados à seleção, formação e desempenho dos cães de detecção (K9) de narcóticos.

ABSTRACT: Considered one of the best odor detectors, dogs go through a rigorous selection and training process. Based on learning theories, modern techniques are used for dog training, respecting individual characteristics, efficiency, and well-being. Since narcotics detection work is perceived as a “play” for the dog, in practice, this promotes a high use rate in the service. The performance of handlers influences the work of the dogs, and well-trained and well-run dogs must work comfortably and accurately. This paper aimed to review the aspects related to the selection, training, and performance of narcotics detection dogs.