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Moraes, M.

Publications and source records attributed to Moraes, M..

2 recordsLinked to original sources

Follow-up of a hospital cohort during the first 3,530 suspected cases of COVID-19 in Sao Jose do Rio Preto, Sao Paulo, Brazil

IntroductionIn a global context, COVID-19 is the most significant health threat in the present days, evidenced by the fact that, in just over four months, SARS-CoV-2 has spread to 171 countries, reaching a Pandemic status. Most patients with COVID-19 have a mild course of the disease. However, approximately 20% develop severe illness with a high mortality rate which is associated with age, comorbidities, and immunosuppression. Epidemiological studies are used to reveal the extent of viral spread in homes, communities, and hospitals. Thus, preventive and control measures can be established by the authorities. ObjectiveIn this study, patients with suspect COVID-19 symptoms who search for hospital care at the city of Sao Jose do Rio Preto (Sao Paulo, Brazil) were monitored, in order to identify the first case of this new disease in the region. In the first two months (March and April), more than 3000 individuals looked for the public and private health system with suspected respiratory symptoms, but only 164 (8.4%) were COVID-19 confirmed. ResultsFrom those, males (56.1%) and patients of the age distribution of 16-59 (91.2%), with diarrhea (22.2%), runny nose (25%), altered taste (15.9%), and anosmia (11.6%) presented statistical significance, although none comorbidities were related with COVID-19 occurrence. The odds ratio analysis supports this finding. Days of onset of symptoms are positively associated with whit viral load, and the same happens with the occurrence of symptoms (dyspnea and low saturation).

molecular biology

BRET sensors unravel that Plasmodium falciparum serpentine receptor 12 (PfSR12) increases surface expression of mammalian GPCRs in HEK293 cells

Considered a significant public health issue, the growing resistance to conventional antimalarials necessitates the identification of new targets for drug development. Given that G protein-coupled receptors (GPCRs) are readily druggable targets, we explored the cellular role and potential structure of a GPCR-like protein identified in the P. falciparum genome, serpentine receptor 12 (SR12). Alphafold structure analysis, coupled with molecular dynamics simulations of SR12, revealed structural similarities to the Golgi dynamics domain (GOLD)-seven-transmembrane helix protein family (GOST proteins). This family of proteins, which includes TMEM87A and the orphan GPCRs GPR180, GPR107, and GPR108, is involved in subcellular trafficking. Consistent with such a trafficking role, SR12 is mainly present in the secretory pathway when expressed in mammalian cells. Co-expression of SR12 with GPCRs PAR1 and M3R led to increased plasma membrane targeting of these receptors. SR12 expression in HEK293 cells conferred Gq-dependent calcium signaling in response to the protease activated receptor 1 (PAR1) agonist thrombin. This response was completely abrogated in cells genetically devoid of PARs (PAR KO cells), consistent with its functions as a chaperone-like protein, promoting receptor trafficking to the plasma membrane. Taken together, the data show that the Plasmodium falciparum SR12 promotes GPCR trafficking when expressed in mammalian cells. Although the physiological consequences of such activity remain to be determined, the finding revealed the presence of a GOST protein in the parasite genome.

cell biology