First report of fatal fungemia due Fusarium oxysporum in a patient with COVID-19 in Ecuador.

Filamentous fungal infections are an important cause of systemic infections in immunocompromised patients. Fusarium genus members potentially cause disseminated infections, especially in patients with catheters, due to the ability to adhere to these devices. We describe a case of fatal fungemia due to Fusarium oxysporum in a patient with COVID-19 in Ecuador. The genus identification was carried out with conventional techniques and species identification by molecular and phylogenetic techniques through sequencing of the ITS region.

Routine Immunization Programs for Children during the COVID-19 Pandemic in Ecuador, 2020-Hidden Effects, Predictable Consequences.

The COVID-19 pandemic has led to a global disruption of several services, including routine immunizations. This effect has been described in several countries, but there are few detailed studies in Latin America and no reports in Ecuador. Therefore, this work aims to quantify the reduction in routine immunizations for infants during the 2020 COVID-19 pandemic in Ecuador. 2018, 2019, and 2020 data were obtained from the Ministry of Health, Ecuador. The number of doses and the extent of immunization coverage was descriptively compared for four vaccines: rotavirus (ROTA), poliovirus (PV), pneumococcal (PCV), and pentavalent (PENTA) vaccines. There was no significant difference in doses applied during the 2018 and 2019 years. However, a significant (p < 0.05) drop of 137,000 delivered doses was observed in 2020 compared to the pre-pandemic years. Reductions in the percentage of coverage were more pronounced for the PENTA vaccine (17.7%), followed by PV (16.4%), ROTA (12%), and PCV vaccines (10.7%). Spatial analysis shows a severe impact on vaccination coverage on provinces from the Coast and Highland regions of the country. The pandemic has significantly impacted the immunization programs for infants across Ecuador. This retrospective analysis shows an urgent need to protect vulnerable zones and populations during public health emergencies.

Identification and characterization of a calmodulin binding domain in the plasma membrane Ca2+-ATPase from Trypanosoma equiperdum.

The plasma membrane Ca2+-ATPase (PMCA) from trypanosomatids lacks a classical calmodulin (CaM) binding domain, although CaM stimulated activities have been detected by biochemical assays. Recently we proposed that the Trypanosoma equiperdum CaM-sensitive PMCA (TePMCA) contains a potential 1-18 CaM-binding motif at the C-terminal region of the pump. In the present study, we evaluated the potential CaM-binding motifs using CaM from Trypanosoma cruzi and either the recombinant full length TePMCA C-terminal sequence (P14) or synthetic peptides comprising different regions of the C-terminal domain. We demonstrated that P14 and a synthetic peptide corresponding to residues 1037-1062 (which contains the predicted 1-18 binding motif) competed efficiently for binding to TcCaM, exhibiting similar IC50s of 200 nM. A stable complex of this peptide and TcCaM was formed in the presence of Ca2+, as determined by native-polyacrylamide gel electrophoresis. A predicted structure obtained by molecular docking showed an interaction of the 1-18 binding motif with the Ca2+/CaM complex. Moreover, when the peptide was incubated with CaM and Ca2+, a blue shift in the tryptophan fluorescence spectrum (from 350 to 329 nm) was observed. Substitutions at W1039 and F1056, strongly decreased both CaM-peptide interaction and the complex assembly. Our results demonstrated the presence of a functional 1-18 motif at the TePMCA C-terminal domain. Furthermore, on the basis of spectrofluorometric assays and the resulting structure modeled by docking we propose that the L1042 and W1060 residues might also participate as anchors to form a 1-4-18-22 motif.

Evidence of the presence of a calmodulin-sensitive plasma membrane Ca2+-ATPase in Trypanosoma equiperdum.

Trypanosoma equiperdum belongs to the subgenus Trypanozoon, which has a significant socio-economic impact by limiting animal protein productivity worldwide. Proteins involved in the intracellular Ca2+ regulation are prospective chemotherapeutic targets since several drugs used in experimental treatment against trypanosomatids exert their action through the disruption of the parasite intracellular Ca2+ homeostasis. Therefore, the plasma membrane Ca2+-ATPase (PMCA) is considered as a potential drug target. This is the first study revealing the presence of a PMCA in T. equiperdum (TePMCA) showing that it is calmodulin (CaM) sensitive, revealed by ATPase activity, western-blot analysis and immuno-absorption assays. The cloning sequence for TePMCA encodes a 1080 amino acid protein which contains domains conserved in all PMCAs so far studied. Molecular modeling predicted that the protein has 10 transmembrane and three cytoplasmic loops which include the ATP-binding site, the phosphorylation domain and Ca2+ translocation site. Like all PMCAs reported in other trypanosomatids, TePMCA lacks a classic CaM binding domain. Nevertheless, this enzyme presents in the C-terminal tail a region of 28 amino acids (TeC28), which most likely adopts a helical conformation within a 1-18 CaM binding motif. Molecular docking between Trypanosoma cruzi CaM (TcCaM) and TeC28 shows a significant similarity with the CaM-C28PMCA4b reference structure (2kne). TcCaM-TeC28 shows an anti-parallel interaction, the peptide wrapped by CaM and the anchor buried in the hydrophobic pocket, structural characteristic described for similar complexes. Our results allows to conclude that T. equiperdum possess a CaM-sensitive PMCA, which presents a non-canonical CaM binding domain that host a 1-18 motif.