SARS-CoV-2's brain impact: revealing cortical and cerebellar differences via cluster analysis in COVID-19 recovered patients

BACKGROUND

COVID-19 is a disease known for its neurological involvement. SARS-CoV-2 infection triggers neuroinflammation, which could significantly contribute to the development of long-term neurological symptoms and structural alterations in the gray matter. However, the existence of a consistent pattern of cerebral atrophy remains uncertain.

OBJECTIVE

Our study aimed to identify patterns of brain involvement in recovered COVID-19 patients and explore potential relationships with clinical variables during hospitalization.

METHODOLOGY

In this study, we included 39 recovered patients and 39 controls from a pre-pandemic database to ensure their non-exposure to the virus. We obtained clinical data of the patients during hospitalization, and 3 months later; in addition we obtained T1-weighted magnetic resonance images and performed standard screening cognitive tests.

RESULTS

We identified two groups of recovered patients based on a cluster analysis of the significant cortical thickness differences between patients and controls. Group 1 displayed significant cortical thickness differences in specific cerebral regions, while Group 2 exhibited significant differences in the cerebellum, though neither group showed cognitive deterioration at the group level. Notably, Group 1 showed a tendency of higher D-dimer values during hospitalization compared to Group 2, prior to p-value correction.

CONCLUSION

This data-driven division into two groups based on the brain structural differences, and the possible link to D-dimer values may provide insights into the underlying mechanisms of SARS-COV-2 neurological disruption and its impact on the brain during and after recovery from the disease.

Life cycle assessment of swine and dairy manure: pyrolysis and combustion processes

The valorization of three different manure samples via pyrolysis and combustion processes was evaluated. Dairy manure (sample Pre) was biologically pretreated by anaerobic digestion (sample Dig R) whereas swine manure (sample SW) was pretreated by a biodrying process. Thermal behavior of manure samples were studied by means of thermogravimetric analysis coupled with mass spectrometry (TGA-MS). These processes could be divided into four general stages: dehydration, devolatilization, char transformation (oxidation for combustion) and inorganic matter decomposition. The main differences observed among the samples were attributed to their different composition and pretreatment. The economic feasibility, energetic and environmental impacts of pyrolysis and combustion technologies for dairy samples were carried out by means of life cycle assessment (LCA) methodology. Four different scenarios were analyzed. The economic feasibility of the pyrolysis process was demonstrated, being sample Dig R the best environmental option. However, the combustion of sample Pre was the best energetic option.