Project description:Arthropod-borne viruses (arboviruses) represent a threat to global public health, especially in the tropical and subtropical regions of the world. More than 150 arboviruses can infect humans; they cause mainly febrile illness, although hemorrhagic complications and diseases affecting the central nervous system (SNC) can also be observed. Arboviruses represent a threat to Brazil and, therefore, a permanent surveillance of these viruses is required to timely reduce the risk of epidemic outbreaks. The Brazilian Amazon region is where the highest number of arboviruses has been detected in the world. Besides, malaria is also endemic in the Amazon region, with a significant predominance of Plasmodium vivax. It is often difficult to differentiate between malaria and arboviral diseases, as they share similar clinical features and laboratory findings, mainly undifferentiated fever. This study aimed to estimate possible viral etiology in patients with febrile syndrome negative for Plasmodium infection, in the Brazilian Amazon. We initially analyzed serum samples of 124 participants with a DNA microarray platform designed for the detection of arboviruses and viruses transmitted by small mammals, but no virus was detected. Then, the serum samples of 76 participants were analyzed with a deep New Generation Sequencing, which showed evidence of the presence of only one arbovirus, the Zika virus in only one pool of 9 serum samples. This result is in contrast with our hypothesis, showing that arboviruses are not frequent in suspected malaria cases in Manaus, Brazil. Other viruses instead of arboviruses were found in this study. Primate erythrovirus 1 was the virus most frequently found virus in the suspected malaria patients, followed by Enterobacteria phage lambda. Besides, we detected, in a lower frequency, the Pegivirus C. In addition to the exogenous viruses, we also detected human endogenous retrovirus in all pools. Due to the high number of viruses that are important in the differential diagnosis of malaria, cost-effective and simple high throughput methods are required, helping molecular surveillance of misdiagnosed viral infections. Further studies with more robust sample sizes in other areas in the Amazon are needed.
Project description:The Amazon molly is a unique clonal fish species that originated from an interspecies hybrid between Poecilia species P. mexicana and P. latipinna. It reproduces by gynogenesis, which eliminates paternal genomic contribution to offspring. Earlier study showed that Amazon molly exhibits bi-allelic expression for a large portion of the genome, leading to two main questions: 1. Are the allelic expression patterns from the initial hybridization event stabilized or changed during establishment of the asexual species and its further evolution? 2. Is allelic expression biased toward one parental allele a stochastic or adaptive process? To answer these questions, the allelic expression of P. formosa siblings was assessed to investigate intra- and inter-cohort allelic expression variability. For comparison, interspecies hybrids between P. mexicana and P. latipinna were produced in the laboratory to represent the P. formosa ancestor. We have identified inter-cohort and intra-cohort variation in parental allelic expression. The existence of inter-cohort divergence suggests functional P. formosa allelic expression patterns do not simply reflect the atavistic situation of the first interspecies hybrid but potentially result from long-term selection of transcriptional fitness. In addition, clonal fish exhibit a transcriptional trend representing minimal intra-clonal variability in allelic expression patterns compared to the corresponding hybrids. The intra-clonal similarity in gene expression translates to sophisticated genetic functional regulation at the individuum level. These findings suggest the parental alleles inherited by P. formosa form tightly regulated genetic networks that lead to a stable transcriptomic landscape within clonal individuals.
Project description:The Amazon river basin receives ~2000 mm of precipitation annually and contributes ~17% of global river freshwater input to the oceans; its hydroclimatic variations can exert profound impacts on the marine ecosystem in the Amazon plume region (APR) and have potential far-reaching influences on hydroclimate over the tropical Atlantic. Here, we show that an amplified seasonal cycle of Amazonia precipitation, represented by the annual difference between maximum and minimum values, during the period 1979-2018, leads to enhanced seasonalities in both Amazon river discharge and APR ocean salinity. An atmospheric moisture budget analysis shows that these enhanced seasonal cycles are associated with similar amplifications in the atmospheric vertical and horizontal moisture advections. Hierarchical sensitivity experiments using global climate models quantify the relationships of these enhanced seasonalities. The results suggest that an intensified hydroclimatological cycle may develop in the Amazonia atmosphere-land-ocean coupled system, favouring more extreme terrestrial and marine conditions.