26 research outputs found
Genomic history of coastal societies from eastern South America
Sambaqui (shellmound) societies are among the most intriguing archaeological phenomena in pre-colonial South America, extending from approximately 8,000 to 1,000 years before present (yr bp) across 3,000 km on the Atlantic coast. However, little is known about their connection to early Holocene hunter-gatherers, how this may have contributed to different historical pathways and the processes through which late Holocene ceramists came to rule the coast shortly before European contact. To contribute to our understanding of the population history of indigenous societies on the eastern coast of South America, we produced genome-wide data from 34 ancient individuals as early as 10,000 yr bp from four different regions in Brazil. Early Holocene hunter-gatherers were found to lack shared genetic drift among themselves and with later populations from eastern South America, suggesting that they derived from a common radiation and did not contribute substantially to later coastal groups. Our analyses show genetic heterogeneity among contemporaneous Sambaqui groups from the southeastern and southern Brazilian coast, contrary to the similarity expressed in the archaeological record. The complex history of intercultural contact between inland horticulturists and coastal populations becomes genetically evident during the final horizon of Sambaqui societies, from around 2,200 yr bp, corroborating evidence of cultural change
Ceratocystis fimbriata isolates on Mangifera indica have different levels of aggressiveness
Mango is amongst the most exported fruits worldwide and the mango tree has been cultivated in many countries with tropical and subtropical climates. Currently, Ceratocystis wilt caused by Ceratocystis fimbriata is among the most important diseases on mango tree. Planting of resistant genotypes is the best strategy for disease control. In the selection of resistant plants a highly aggressive isolate should be used in inoculations under controlled conditions. Thus, the objective of this study was to evaluate whether there are differences in aggressiveness among isolates of C. fimbriata obtained from diseased mango trees in Brazil. Before inoculation, five randomly selected isolates were tested for sporulation and mycelial growth in different culture media in order to select the best conditions for inoculum production. Twenty-four isolates from the States of SĂŁo Paulo, Rio de Janeiro, Minas Gerais and Mato Grosso do Sul were inoculated in the susceptible mango cultivar Espada. Subsequently, the four most aggressive isolates were inoculated in other five different mango cultivars. The culture media MEA provided the best levels of sporulation and mycelial growth for four of the five tested isolates. Isolates SEMG1-1 from Minas Gerais and SESP8-3 from SĂŁo Paulo were the most aggressive. The response of cultivars to the most aggressive isolates tested in the present work varied from highly resistant to highly susceptible, âUbĂĄâ being the most resistant regardless of the isolate tested. These results demonstrate that there are significant differences in aggressiveness among C. fimbriata isolates from mango in Brazil, as well as cultivarâĂâisolate interaction
Genetic variation, morphology and pathogenicity of Ceratocystis fimbriata on Hevea brasiliensis in Brazil
Ceratocystis fimbriata causes diseases on a wide variety of plants in Brazil, including rubber tree (Hevea brasiliensis), on which it causes gray mold or moldy rot on tapping panels affecting latex yield. However, C. fimbriata isolated from rubber tree have not been critically studied. Phylogenetic analyses of sequences of ITS rDNA and a mating type gene placed rubber tree isolates from Acre and Bahia among Brazilian isolates of C. fimbriata from other hosts. In the analyses of 14 microsatellite loci, the rubber tree isolates from Bahia were identical to each other and had alleles similar to those of Brazilian isolates from mango and eucalyptus. The microsatellite alleles of the Acre rubber tree isolates were identical to each other but distinct from other Brazilian isolates. The rubber tree isolates were morphologically indistinguishable from each other and very similar to the isolates of C. fimbriata on Ipomoea batatas, on which the species was originally described. Based on inoculation experiments results, the Bahia and Acre rubber tree isolates do not appear to be host specialized, which is typical for Brazilian isolates of C. fimbriata sensu stricto
Interleukin-6 and C-Reactive Protein Are Overexpressed in the Liver of Perinatal Deaths Diagnosed with Fetal Inflammatory Response Syndrome
Anatomopathologic studies have failed to define the fetal inflammatory response syndrome (FIRS) as a cause of fetal death. Here, liver fragments of perinatal autopsies were collected at a university hospital from 1990 to 2009 and classified according to the cause of death, perinatal stress, and gestational age (GA) of the fetus. IL-6, TNF-α, and C-reactive protein (CRP) expression were immunostained, respectively, with primary antibody. Cases with congenital malformation, ascending infection, and perinatal anoxia showed increased IL-6, CRP, and TNF-α, respectively. Prematures presented higher expression of IL-6 whereas term births showed higher expression of CRP. Cases classified as acute stress presented higher expression of IL-6 and TNF-α and cases with chronic stress presented higher expression of CRP. GA correlated negatively with IL-6 and positively with CRP and TNF-α. Body weight correlated negatively with IL-6 and positively with CRP and TNF-α. Despite the diagnosis of FIRS being clinical and based on serum parameters, the findings in the current study allow the inference of FIRS diagnosis in the autopsied infants, based on an in situ liver analysis of these markers