Case Series: Report of the First Two Human Indigenous Cases of <Emphasis Type="Italic">Cryptococcus gattii</Emphasis> Infection in Eastern Canada

We report the two first cases of human C. gattii meningoencephalitis acquired on the Canadian east coast, from the province of Quebec. Unlike C. neoformans, C. gattii is not known to have an established ecological niche on the North American east coast. C. gattii has recently been responsible for major outbreaks in British Columbia, Canada, and in the American pacific northwest. However, no human cases acquired in other Canadian provinces have been reported to our knowledge. The source of acquisition remains unclear for both patients but since neither had traveled outside of the province of Quebec, we discuss the possibilities of environmental and animal-associated acquisition, as well as the possible established endemicity in new areas. These cases add to the growing reported human and animal cases in areas previously not thought to be endemic for C. gattii.     

Biotechnological potential of plant growth-promoting bacteria from the roots and rhizospheres of endemic plants in ironstone vegetation in southeastern Brazil

Microorganisms associated with plants have a great biotechnological potential, but investigations of these microorganisms associated with native plants in peculiar environments has been incipient. The objective of this study was to analyze the plant growth-promoting bacteria potential of cultivable bacteria associated with rare plants from the ferruginous rocky fields of the Brazilian Iron Quadrangle. The roots and rhizospheres of nine endemic plants species and samples of a root found in a lateritiric duricrust (canga) cave were collected, the culturable bacteria isolated and prospected for distinct biotechnological and ecological potentials. Out of the 148 isolates obtained, 8 (5.4%) showed potential to promote plant growth, whereas 4 (2.7%) isolates acted as biocontrol agents against Xanthomonas citri pathotype A (Xac306), reducing the cancrotic lesions by more than 60% when co-inoculated with this phytopathogen in Citrus sinensis plants. Moreover, other 4 (2.7%) isolates were classified as potential bioremediation agents, being able to withstand high concentrations of arsenite (5 mM As³⁺) and arsenate (800 mM As⁵⁺), by removing up to 35% and 15% of this metalloid in solution, respectively. These same four isolates had a positive influence on the growth of both the roots and the aerial parts when inoculated with tomato seeds in the soil contaminated with arsenic. This is the first time that an investigation highlights the potentialities of bacteria associated with rare plants of ferruginous rocky fields as a reservoir of microbiota of biotechnological and ecological interest, highlighting the importance of conservation of this area that is undergoing intense anthropic activity.

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Functional impairment of MSC induced by transient warming events: Correlation with loss of adhesion and altered cell size

Background

We recently showed that transient warming effects decreased the functional and adhesion properties of mesenchymal stromal cells (MSC) while post-thaw viability remained high. In an attempt to better predict functional impairment of cryopreserved MSC, we further analysed the correlation between viability, immunosuppressive activity and adhesion of cells exposed or not to warming events.

Cord blood–derived cytokine-induced killer cells combined with blinatumomab as a therapeutic strategy for CD19+ tumors

Background

Cytokine-induced killer cells (CIKs) are an advanced therapeutic medicinal product (ATMP) that has shown therapeutic activity in clinical trials but needs optimization. We developed a novel strategy using CIKs from banked cryopreserved cord blood units (CBUs) combined with bispecific antibody (BsAb) blinatumomab to treat CD19⁺ malignancies.

Estimating consumable biomass from body length and order in insects and spiders

1. Current models used to estimate insect prey biomass for diet studies use whole weight. However, a large proportion of an arthropod's body is taken up by an indigestible exoskeleton, leading to erroneous estimation of the food intake of insectivorous animals. 2. Linear mixed effect models were used to obtain equations to predict consumable biomass from body length for a variety of Neotropical insects and spiders. These data were obtained by feeding taxa of various orders to groups of 100 social spiders and comparing pre‐ and post‐consumption weights using size‐matched controls. 3. Significant linear relationships were found relating body size to consumed biomass for all orders, with slopes ranging from 1.276 to 4.011 and R² values from 0.476 to 0.929. For orders other than spiders and Orthoptera, the increase in weight with size exhibited negative allometric scaling, suggesting a decrease in tissue density, or an increase in internal air space, with size. 4. Although there were significant differences across taxonomic orders in the proportion of biomass consumed, within most orders the proportion consumed did not differ significantly with body size. The estimated regression coefficients may be used by other workers to estimate consumable biomass of arthropod prey for studies requiring large sample sizes or non‐lethal sampling of rare or endangered species.     

In vitro establishment of nitrogen-fixing strawberry (Fragaria × ananassa) via artificial symbiosis with Azomonas insignis

Summary Artificial symbiosis was established between diazotrophic Azomonas insignis and strawberry (Fragaria × ananassa). The partnership was created by in vitro techniques through callus induction and organogenesis. Suitable micropropagation [M3=Murashige and Skoog (1962) (MS) basal medium supplemented with 2.5 μM N⁶-benzyladenine (BA), 0.3 μM gibberellic acid (GA₃), 2.2 μM indole-3-butyric acid (IBA), and 3% sucrose] and plant regeneration [R3=MS mineral salts+555 μM myo-inositol, 1.2 μM thiamine HCl, 4.4 μM BA, 0.5 μM IBA, 0.3 μM α-naphthaleneacetic acid (NAA), 0.5 μM 2,4-dichlorophenoxyacetic acid (2,4-D)] media were developed for the test cultivar Fert?di F5. New shoots containing bacteria were rooted, acclimatized, and planted outdoors. The basis of the partnership during the in vitro phase is the bacterial dependence on the plant metabolic activity, using maltose in the medium as carbon and energy source that can be utilized by the plant cells only. The presence of bacteria in the intercellular spaces of the callus tissues and regenerated plants was proved by re-isolation and microscopic techniques. Nitrogenase activity was also detected in the plant tissues.     

Low Resolution Structure of Glyceraldehyde 3-Phosphate Dehydrogenase

The structure of the holo enzyme shows that the four chemically identical sub-units are arranged with almost perfect 222 symmetry. There are indications, however, that the active centre regions might only be related in pairs.     

Non-native fish species in Neotropical freshwaters: how did they arrive,and where did they come from?

The invasion of aquatic ecosystems by introduced invasive alien species (IAS) has become a worldwide phenomenon, and often leads to competitive interactions with native species. At high-nutrient levels, native species mostly are outcompeted by the introduced species. We performed an outdoor competition experiment between IAS free-floating Lemna minuta and native Lemna minor in a eutrophicated pond to examine whether the invasive species is the better competitor. We additionally performed an indoor experiment resembling mesotrophic phosphorus (P) conditions to investigate both species’ competitiveness in low P availability and compared with previous experiments at high-nutrient levels. Our results showed that in field conditions, the alien L. minuta was the better competitor. In the mesotrophic indoor condition, however, the native L. minor was the better competitor. Both species produced longer roots in the indoor experiment compared to field conditions. The species’ relative growth rates were also lower in the indoor experiment. A P reduction to mesotrophic condition in the water column thus might reduce invasive L. minuta growth and competitive performance. Additionally, introduction and recovery of L. minor could reduce L. minuta cover, but only following P reduction. Field experiments in mesotrophic ponds are needed to confirm these indoor findings.     

Vertical oviposition activity of mosquitoes in the Atlantic Forest of Brazil with emphasis on the sylvan vector,Haemagogus leucocelaenus (Diptera: Culicidae)

This study aimed to assess the vertical patterns of oviposition and temporal changes in the distribution of mosquito species in an area of the Atlantic Forest in Rio de Janeiro State, Brazil, and in particular, the behavior and oviposition of potential yellow fever virus vectors. Mosquito samples were collected from the Ecological Reserve Guapiaçu (REGUA, Brazil), which includes a somewhat disturbed forest, with a large diversity of plants and animals. In all, 5,458 specimens (ten species from seven genera) were collected. Haemagogus leucocelaenus was the most frequently captured species, representing 73% of the specimens collected. Species richness and diversity were the highest in the samples collected from the ground‐level ovitraps and decreased with height. Species composition also differed significantly among heights. The largest species differences were detected between ovitraps set at the ground level and those set at 7 m and 9 m; Hg. leucocelaenus, Limatus durhamii, and Limatus paraensis contributed most to these differences. Sampling month and climatic variables had significant effects on species richness and diversity. Species diversity and richness decreased with height, suggesting that the conditions for mosquito breeding are more favorable closer to the ground. Species composition also showed vertical differences.