Evolution of growth traits in invasive Pereskia aculeata (Cactaceae): testing the EICA hypothesis using its specialist herbivore, Catorhintha schaffneri (Coreidae).

BACKGROUND: Species introduced into new habitats are fitter than their native populations, as hypothesized by the 'evolution of increased competitive ability' (EICA). Here, Pereskia aculeata Miller was used as a model to test EICA and explore how 'enemy release' may have influenced the invasion success of its 400-year-old introduced populations (genotypes) compared with native populations. Plant growth traits (height and shoot length) of 15 genotypes [four from the introduced range (South Africa) and 11 from the native range (Brazil and Argentina, Venezuela and The Dominican Republic)] were assessed. Damage and impact of a shoot-feeding, sap-sucking specialist Catorhintha schaffneri Brailovsky & Garcia on ten genotypes were also compared. RESULTS: All but one of the invasive genotypes were significantly taller than native genotypes. Although the invasive genotypes were relatively more damaged by herbivory than some of the native genotypes, the observed differences were not explained completely by their origins. Nonetheless, the findings partially supported the predictions of the EICA hypothesis because invasive genotypes were generally taller than native genotypes, but did not fully support the hypothesis because they were not always more damaged than the native genotypes by C. schaffneri. CONCLUSION: Invasive genotypes had an advantage in the introduced range as they can climb neighbouring vegetation more quickly than native genotypes, but the damage incurred by the invasive genotypes relative to the native genotypes suggests only that C. schaffneri would be as damaging in South Africa, where it serves as a biocontrol agent, as it is in its native distribution in Brazil. © 2020 Society of Chemical Industry.

The South America Tomato Leafminer, Tuta absoluta (Lepidoptera: Gelechiidae), Spreads Its Wings in Eastern Africa: Distribution and Socioeconomic Impacts.

Following the arrival of Tuta absoluta Meyrick in the eastern African subregion in 2012, several studies have shown numerous ecological aspects of its invasion. We investigated the impact of T. absoluta on people's livelihoods across four counties of Kenya. Here, 200 farmers in the country were interviewed in person using semistructured questionnaires. In addition to livelihood surveys, T. absoluta distribution was mapped between 2016 and 2018 to determine its current distribution across four countries (Kenya, Sudan, Tanzania, and Uganda) in the subregion. Albeit a recent invader, T. absoluta is abundant and distributed throughout the subregion and is viewed as the worst invasive alien species of agriculturally sustainable livelihoods by tomato farmers. The arrival of T. absoluta in the subregion has resulted in livelihood losses and increased both the cost of tomato production and frequency of pesticide application. We recommend the implementation of biological control along, with other control measures in an integrated approach, against T. absoluta in the subregion, where its impact on sustainable livelihoods is serious and long-term control strategies are required to curb its detrimental effects.

Efficacy and safety of ursodeoxycholic acid in patients with intrahepatic cholestasis of pregnancy.

UNLABELLED:  Background and aims. Patients with intrahepatic cholestasis of pregnancy (ICP) benefit from ursodeoxycholic acid (UDCA) treatment. Since there is still certain reluctance to use UDCA in pregnant women, mainly due to warnings in the official SPC information in respective drug leaflets, our objective was to assess the efficacy and safety of UDCA during pregnancy. MATERIAL AND METHODS: Our retrospective multicentric study was performed on 191 consecutive pregnant women with ICP treated with UDCA. Any maternal and/or fetal complications of the UDCA treatment were searched for; healthy pregnant women (n = 256) served as controls. RESULTS: The UDCA treatment improved liver disease status in the majority of the affected women (86.1%). This treatment was well tolerated, with only negligible skin reactions (0.5%) and mild diarrhea (4.7%). No complications attributable to UDCA treatment were detected during the fetal life, delivery, or the early neonatal period. CONCLUSION: We confirmed the good efficacy and safety of UDCA treatment in pregnancy for both mothers and fetuses/neonates.

Short communication: Human blood dendritic cells are infected separately from monocytes in HIV type 1 patients.

Monocytes serve as a systemic reservoir of myeloid precursors for the renewal of tissue macrophages and dendritic cells (DCs). Both monocytes and dendritic cells can be infected with HIV-1. Circulating DCs are believed to be derived from a common precursor of monocytes, or, in the case of inflammatory challenge, from monocytes directly. Because there are fewer infected blood monocytes than infected cells after differentiation, we hypothesized that the majority of HIV-1 infection in circulating DCs occurs via direct viral binding to their CD4 and coreceptors after differentiation. We isolated monocytes at one time point and circulating dendritic cells at a second time point from the blood of HIV-1-infected patients. Proviral DNA was isolated from DCs and monocytes, and the C2-V4 region of the HIV-1 env gene was cloned and sequenced. Phylogeny, nucleotide distances, and glycosylation patterns of the env gene were performed. The phylogenetic trees revealed that viral forms from the monocytes clustered distantly from the quasispecies derived from circulating DCs. The nucleotide distances and differing glycosylation patterns suggest that the infection of DCs is independent of the infection of the monocytes.

Influence of CD4+ T cell counts on viral evolution in HIV-infected individuals undergoing suppressive HAART.

We analyzed the viral C2-V4 envelope diversity, glycosylation patterns, and dS/dN ratios of plasma HIV-1 in an attempt to better understand the complex interaction between viral quasispecies and the host-selective pressures pre- and post-HAART. Phylogenetic analysis of the envelope gene of five patients revealed monophyletic clustering in patients with higher CD4+ T cell counts and sequence intermingling in those with lower CD4+ T cells in relation to the stage of HAART. Our analyses also showed clear shifts in N-linked glycosylation patterns in patients with higher CD4+ T cells, suggesting possible distinct immunological pressures pre- and post-HAART. The relative preponderance of synonymous/nonsynonymous changes in the envelope region suggested a positive selection in patients with higher CD4+ T cells, whereas lack of evidence for positive selection was found in the patients with lower CD4+ T cells. An exception to the last analysis occurred in the only patient who reached complete viral suppression, maybe due to drug pressure exerted over the pol gene that may obscure the immune pressure/selection at the envelope in this analysis. All these indications may suggest that even when HAART generates viral suppression, quasispecies evolve in the envelope gene probably resulting from host-selective pressure.

Changes in the human immunodeficiency virus V3 region that correspond with disease progression: a meta-analysis.

In order to determine the changes in the human immunodeficiency virus type-1 (HIV-1) envelope that corresponds with disease progression, a meta-analysis of viral forms was performed using HIV-1 sequences obtained from GenBank. Studies were selected that included longitudinally derived V3 envelope region sequences from multiple time points along with CD4 values as a marker of disease progression. Studies with a total of 58 subjects, 327 time points, and 380,000 total amino acid residues were included in this meta-analysis. Changes at specific amino acid sites over the course of disease progression stages were analyzed. The most common specific changes were found at amino acid sites 324D to N, 306S/G to R, and 360N to R. Other sites had changes from one amino acid type to another including the appearance of a basic form at 327, a charged form at 319, and 320D/E changing to basic or neutral. The timing of these changes was contrasted to CD4 decline with changes at 324 and 327 appearing before and 306, 320, and 319 appearing after the initiation of CD4 decline.