There is a deep need for mortality predictors that allow clinicians to quickly triage patients with severe coronavirus disease 2019 (Covid-19) into intensive care units at the time of hospital admission. Thus, we examined the efficacy of the lymphocyte-to-neutrophil ratio (LNR) and neutrophil-to-monocyte ratio (NMR) as predictors of in-hospital death at admission in patients with severe Covid-19. A total of 54 Mexican adult patients with Covid-19 that met hospitalization criteria were retrospectively enrolled, followed-up daily until hospital discharge or death, and then assigned to survival or non-survival groups. Clinical, demographic, and laboratory parameters were recorded at admission. A total of 20 patients with severe Covid-19 died, and 75% of them were men older than 62.90 ± 14.18 years on average. Type 2 diabetes, hypertension, and coronary heart disease were more prevalent in non-survivors. As compared to survivors, LNR was significantly fourfold decreased while NMR was twofold increased. LNR ≤ 0.088 predicted in-hospital mortality with a sensitivity of 85.00% and a specificity of 74.19%. NMR ≥ 17.75 was a better independent risk factor for mortality with a sensitivity of 89.47% and a specificity of 80.00%. This study demonstrates for the first time that NMR and LNR are accurate predictors of in-hospital mortality at admission in patients with severe Covid-19.

SARS-CoV-2 causes COVID-19, which has claimed millions of lives. This virus can infect various cells and tissues, including the brain, for which numerous neurological symptoms have been reported, ranging from mild and non-life-threatening (e.g., headaches, anosmia, dysgeusia, and disorientation) to severe and life-threatening symptoms (e.g., meningitis, ischemic stroke, and cerebral thrombosis). The cellular receptor for SARS-CoV-2 is angiotensin-converting enzyme 2 (ACE2), an enzyme that belongs to the renin-angiotensin system (RAS). RAS is an endocrine system that has been classically associated with regulating blood pressure and fluid and electrolyte balance; however, it is also involved in promoting inflammation, proliferation, fibrogenesis, and lipogenesis. Two pathways constitute the RAS with counter-balancing effects, which is the key to its regulation. The first axis (classical) is composed of angiotensin-converting enzyme (ACE), angiotensin (Ang) II, and angiotensin type 1 receptor (AT1R) as the main effector, which -when activated- increases the production of aldosterone and antidiuretic hormone, sympathetic nervous system tone, blood pressure, vasoconstriction, fibrosis, inflammation, and reactive oxygen species (ROS) production. Both systemic and local classical RAS’ within the brain are associated with cognitive impairment, cell death, and inflammation. The second axis (non-classical or alternative) includes ACE2, which converts Ang II to Ang-(1–7), a peptide molecule that activates Mas receptor (MasR) in charge of opposing Ang II/AT1R actions. Thus, the alternative RAS axis enhances cognition, synaptic remodeling, cell survival, cell signal transmission, and antioxidant/anti-inflammatory mechanisms in the brain. In a physiological state, both RAS axes remain balanced. However, some factors can dysregulate systemic and local RAS arms. The binding of SARS-CoV-2 to ACE2 causes the internalization and degradation of this enzyme, reducing its activity, and disrupting the balance of systemic and local RAS, which partially explain the appearance of some of the neurological symptoms associated with COVID-19. Therefore, this review aims to analyze the role of RAS in the development of the neurological effects due to SARS-CoV-2 infection. Moreover, we will discuss the RAS-molecular targets that could be used for therapeutic purposes to treat the short and long-term neurological COVID-19-related sequelae.

Background: A diet containing non-caloric sweeteners (NCS) could reduce calorie intake; conversely, some animal studies suggest that NCS consumption may increase functional gastrointestinal disorder symptoms (FGDs). This study aimed to compare the effect of consuming a diet containing NCS (c-NCS) versus a non-caloric sweetener-free diet (NCS-f) on FGDs. Methods: We conducted a randomized, controlled, parallel-group study using two different diets for five weeks: the c-NCS diet contained 50–100 mg/day NCS, whereas the NCS-f diet had less than 10 mg/day NCS. At the beginning of the study (PreTx) and at the end (PostTx), we assessed FGDs, dietary intake, and NCS consumption. Results: The percentage of participants with diarrhea (PreTx = 19% vs. PstTx = 56%; p = 0.02), post-prandial discomfort (PreTx = 9% vs. PstTx = 39%; p = 0.02), constipation (PreTx = 30% vs. PostTx = 56%; p < 0.01), and burning (PreTx = 13% vs. PostTx = 33%; p < 0.01) increased in the c-NCS diet group. Conversely, abdominal pain (PreTx = 15% vs. PostTx = 3%; p = 0.04), post-prandial discomfort (PreTx = 26% vs. PostTx = 6%; p = 0.02), burning (PreTx = 15% vs. PostTx = 0%; p = 0.02), early satiety (PreTx = 18% vs. PostTx = 3%; p < 0.01), and epigastric pain (PreTx = 38% vs. PostTx = 3%; p < 0.01) decreased in the NCS-f diet group. Conclusion: A c-NCS diet is associated with increased FGDs, including diarrhea, post-prandial discomfort, constipation, and burning or retrosternal pain. The NCS-f diet also decreased FGDs, as well as abdominal pain, post-prandial discomfort, burning or retrosternal pain, early satiety, and epigastric pain.

Background: Although the essential components of pain pathways have been identified, a thorough comprehension of the interactions necessary for creating focused treatments is still lacking. Such include more standardised methods for measuring pain in clinical and preclinical studies and more representative study populations. Objective: This review describes the essential neuroanatomy and neurophysiology of pain nociception and its relation with currently available neuroimaging methods focused on health professionals responsible for treating pain. Methods: Conduct a PubMed search of pain pathways using pain-related search terms, selecting the most relevant and updated information. Results: Current reviews of pain highlight the importance of their study in different areas from the cellular level, pain types, neuronal plasticity, ascending, descending, and integration pathways to their clinical evaluation and neuroimaging. Advanced neuroimaging techniques such as fMRI, PET, and MEG are used to better understand the neural mechanisms underlying pain processing and identify potential targets for pain therapy. Conclusions: The study of pain pathways and neuroimaging methods allows physicians to evaluate and facilitate decision-making related to the pathologies that cause chronic pain. Some identifiable issues include a better understanding of the relationship between pain and mental health, developing more effective interventions for chronic pain's psychological and emotional aspects, and better integrating data from different neuroimaging modalities for the clinical efficacy of new pain therapies.