scholarly journals Multiple evolutionary lineages for the main vector of Leishmania guyanensis, Lutzomyia umbratilis (Diptera: Psychodidae), in the Brazilian Amazon

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Vera Margarete Scarpassa ◽  
Antônio Saulo Cunha-Machado ◽  
Ronildo Baiatone Alencar
Keyword(s):  
Phylogenetic Trees ◽  
Isolation By Distance ◽  
Brazilian Amazon ◽  
Amazon River ◽  
Evolutionary Forces ◽  
Negro River ◽  
Genetic Groups ◽  
Brazilian Amazon Region ◽  
Leishmania Guyanensis ◽  
Evolutionary Lineages

AbstractLutzomyia umbratilis is the main vector of Leishmania guyanensis in the Brazilian Amazon and in neighboring countries. Previous biological and molecular investigations have revealed significant differences between L. umbratilis populations from the central Brazilian Amazon region. Here, a phylogeographic survey of L. umbratilis populations collected from nine localities in the Brazilian Amazon was conducted using two mitochondrial genes. Statistical analyses focused on population genetics, phylogenetic relationships and species delimitations. COI genetic diversity was very high, whereas Cytb diversity was moderate. COI genealogical haplotypes, population structure and phylogenetic analyses identified a deep genetic differentiation and three main genetic groups. Cytb showed a shallower genetic structure, two main haplogroups and poorly resolved phylogenetic trees. These findings, allied to absence of isolation by distance, support the hypothesis that the Amazon and Negro Rivers and interfluves are the main evolutionary forces driving L. umbratilis diversification. The main three genetic groups observed represent three evolutionary lineages, possibly species. The first lineage occurs north of the Amazon River and east of Negro River, where Le. guyanensis transmission is intense, implying that L. umbratilis is an important vector there. The second lineage is in the interfluve between north of Amazon River and west of Negro River, an area reported to be free of Le. guyanensis transmission. The third lineage, first recorded in this study, is in the interfluve between south of Amazonas River and west of Madeira River, and its involvement in the transmission of this parasite remains to be elucidated.

scholarly journals Surgical Site Infection Following Caesarean Section by Acinetobacter Species: A Report from a Hyperendemic Setting in the Brazilian Amazon Region

2021 ◽  
Vol 9 (4) ◽  
pp. 743
Author(s):  
Blenda Gonçalves Cabral ◽  
Danielle Murici Brasiliense ◽  
Ismari Perini Furlaneto ◽  
Yan Corrêa Rodrigues ◽  
Karla Valéria Batista Lima
Keyword(s):  
Caesarean Section ◽  
Surgical Site Infection ◽  
Carbapenem Resistance ◽  
Brazilian Amazon ◽  
Amazon Region ◽  
Site Infection ◽  
Acinetobacter Species ◽  
Brazilian Amazon Region ◽  
Acinetobacter Spp ◽  
The Impact

Surgical site infection (SSI) following caesarean section is associated with increased morbidity, mortality, and significant health care costs. This study evaluated the epidemiological, clinical, and microbiological features of Acinetobacter spp. in women with SSIs who have undergone caesarean section at a referral hospital in the Brazilian Amazon region. This study included 69 women with post-caesarean SSI by Acinetobacter spp. admitted to the hospital between January 2012 and May 2015. The 69 Acinetobacter isolates were subjected to molecular species identification, antimicrobial susceptibility testing, detection of carbapenemase-encoding genes, and genotyping. The main complications of post-caesarean SSI by Acinetobacter were inadequate and prolonged antibiotic therapy, sepsis, prolonged hospitalization, and re-suture procedures. A. baumannii, A. nosocomialis and A. colistiniresistens species were identified among the isolates. Carbapenem resistance was associated with OXA-23-producing A. baumannii isolates and IMP-1-producing A. nosocomialis isolate. Patients with multidrug-resistant A. baumannii infection showed worse clinical courses. Dissemination of persistent epidemic clones was observed, and the main clonal complexes (CC) for A. baumannii were CC231 and CC236 (Oxford scheme) and CC1 and CC15 (Pasteur scheme). This is the first report of a long-term Acinetobacter spp. outbreak in women who underwent caesarean section at a Brazilian hospital. This study demonstrates the impact of multidrug resistance on the clinical course of post-caesarean infections.

Population Subdivision and Molecular Sequence Variation: Theory and Analysis of Drosophila ananassae Data

Genetics ◽  
2003 ◽  
Vol 165 (3) ◽  
pp. 1385-1395
Author(s):  
Claus Vogl ◽  
Aparup Das ◽  
Mark Beaumont ◽  
Sujata Mohanty ◽  
Wolfgang Stephan
Keyword(s):  
Sequence Data ◽  
Isolation By Distance ◽  
Allele Frequencies ◽  
Drosophila Ananassae ◽  
Population Subdivision ◽  
Variation Theory ◽  
Peripheral Populations ◽  
Molecular Variation ◽  
Data Set ◽  
Evolutionary Forces

Abstract Population subdivision complicates analysis of molecular variation. Even if neutrality is assumed, three evolutionary forces need to be considered: migration, mutation, and drift. Simplification can be achieved by assuming that the process of migration among and drift within subpopulations is occurring fast compared to mutation and drift in the entire population. This allows a two-step approach in the analysis: (i) analysis of population subdivision and (ii) analysis of molecular variation in the migrant pool. We model population subdivision using an infinite island model, where we allow the migration/drift parameter 0398; to vary among populations. Thus, central and peripheral populations can be differentiated. For inference of 0398;, we use a coalescence approach, implemented via a Markov chain Monte Carlo (MCMC) integration method that allows estimation of allele frequencies in the migrant pool. The second step of this approach (analysis of molecular variation in the migrant pool) uses the estimated allele frequencies in the migrant pool for the study of molecular variation. We apply this method to a Drosophila ananassae sequence data set. We find little indication of isolation by distance, but large differences in the migration parameter among populations. The population as a whole seems to be expanding. A population from Bogor (Java, Indonesia) shows the highest variation and seems closest to the species center.

scholarly journals Inadequate management of natural ecosystem in the Brazilian Amazon region results in the emergence and reemergence of arboviruses

2001 ◽  
Vol 17 (suppl) ◽  
pp. S155-S164 ◽  
Author(s):  
Pedro F. C. Vasconcelos ◽  
Amélia P. A. Travassos da Rosa ◽  
Sueli G. Rodrigues ◽  
Elizabeth S. Travassos da Rosa ◽  
Nicolas Dégallier ◽  
...  
Keyword(s):  
Environmental Changes ◽  
Epidemiological Data ◽  
Brazilian Amazon ◽  
Host Population ◽  
Amazon Region ◽  
Laboratory Animals ◽  
Natural Ecosystem ◽  
Brazilian Amazon Region ◽  
Mining Dam ◽  
The Impact

A total of 187 different species of arboviruses and other viruses in vertebrates were identified at the Evandro Chagas Institute (IEC) from 1954 to 1998, among more than 10,000 arbovirus strains isolated from humans, hematophagous insects, and wild and sentinel vertebrates. Despite intensive studies in the Brazilian Amazon region, especially in Pará State, very little is known about most of these viruses, except for information on date, time, source, and method of isolation, as well as their capacity to infect laboratory animals. This paper reviews ecological and epidemiological data and analyzes the impact of vector and host population changes on various viruses as a result of profound changes in the natural environment. Deforestation, mining, dam and highway construction, human colonization, and urbanization were the main manmade environmental changes associated with the emergence and/or reemergence of relevant arboviruses, including some known pathogens for humans.

Sign in / Sign up

Export Citation Format

Share Document