Role of saprophagous fly biodiversity in ecological processes and urban ecosystem services

1. Direct consumption of organic matter by the saprophagous larvae provides the ecosystem with a fundamental service by recycling nutrients and reducing exposure to decomposing matter. The present study aimed to assess the functional role of saprophagous flies in the mass loss of different types of decomposing organic matter. 2. Two types of common urban waste were used to measure the role of flies in reducing organic matter: chicken viscera (chicken) and a mixture of flour and uncooked eggs (flour and eggs), representing leftover food. Ten traps baited with each substrate, under field conditions, allowed fly access (exposed to flies) and three traps from each substrate did not (unexposed controls); adult flies entering the traps or emerging from the substrates and substrate mass loss were recorded. 3. Species from Calliphoridae, Sarcophagidae, Muscidae, and Fanniidae families were collected mainly in traps baited with chicken, with Phoridae being the most abundant in traps with flour and eggs as bait. A significantly richer (P < 0.05) assemblage of fly species accessed the traps baited with chicken viscera (21 species) compared with those emerging (11 species), whereas similar numbers of species accessed (n = 5) or emerged (n = 1) from traps baited with flour and eggs (average richness accessing 7.97, emerging 2.83). Chicken substrate mass loss and species richness were positively related (r = 0.56, P = 0.001). In traps where richness was larger than 10 species, the substrates were reduced by more than 85% of their initial weight compared with unexposed controls, which lost 30%. Substrate mass loss significantly increased with the abundance of flies (r = 0.73, P < 0.0001). 4. The results of the present study support the functional role of saprophagous species diversity on the decomposition rates of organic matter, reinforcing the negative consequences of loss or gain of species in modified landscapes and for ecosystem function.     

Neuroinvasion of the Highly Pathogenic Influenza Virus H7N1 Is Caused by Disruption of the Blood Brain Barrier in an Avian Model

Influenza A virus (IAV) causes central nervous system (CNS) lesions in avian and mammalian species, including humans. However, the mechanism used by IAV to invade the brain has not been determined. In the current work, we used chickens infected with a highly pathogenic avian influenza (HPAI) virus as a model to elucidate the mechanism of entry of IAV into the brain. The permeability of the BBB was evaluated in fifteen-day-old H7N1-infected and non-infected chickens using three different methods: (i) detecting Evans blue (EB) extravasation into the brain, (ii) determining the leakage of the serum protein immunoglobulin Y (IgY) into the brain and (iii) assessing the stability of the tight-junction (TJ) proteins zonula occludens-1 and claudin-1 in the chicken brain at 6, 12, 18, 24, 36 and 48 hours post-inoculation (hpi). The onset of the induced viremia was evaluated by quantitative real time RT-PCR (RT-qPCR) at the same time points. Viral RNA was detected from 18 hpi onward in blood samples, whereas IAV antigen was detected at 24 hpi in brain tissue samples. EB and IgY extravasation and loss of integrity of the TJs associated with the presence of viral antigen was first observed at 36 and 48 hpi in the telencephalic pallium and cerebellum. Our data suggest that the mechanism of entry of the H7N1 HPAI into the brain includes infection of the endothelial cells at early stages (24 hpi) with subsequent disruption of the TJs of the BBB and leakage of virus and serum proteins into the adjacent neuroparenchyma.     

13C NMR analysis of alkaloids from peschiera fuchsiaefolia

Fractionation of an ethereal extract of Peschiera fuchsiaefolia resulted in the isolation of decarbomethoxyvoacamine, demethylvoacamine, voacamidine, perivine, 16-epiaffinine and voacanginehydroxyindolenine, together with the previously reported alkaloids voacamine, voacangine, voachalotine and affinisine. Analysis of the ¹³C NMR spectra of the bisindole alkaloids and of 16-epiaffinine is reported.     

High Prevalence of Schistosoma mansoni in Six Health Areas of – Kasansa Health Zone,Democratic Republic of the Congo: Short Report

School-aged children suffer the most from schistosomiasis infection in sub Saharan Africa due to poverty and limited sanitary conditions. Mapping of disease burden is recommended and there is a need of updating prevalence data which is as old as 20 years in the Democratic Republic of Congo. An epidemiological and parasitological study was carried out in 2011 in the health zone of Kasansa. Six health areas (HA) were included in the study. In each health area, one primary school was selected. School-aged children were screened for S. mansoni infection using parallel Kato-Katz and direct microscopy techniques. A total of 335 school-aged children were screened. The average prevalence was 82.7% and ranged between 59.5–94.9%. Four of the six HAs had a prevalence level over 91%. Of all infected children, about half 112 (43.2%) had light parasite density. These results demonstrate that Schistosoma mansoni infection is a bigger problem than anticipated and there is an urgent need to implement effective control measures.     

Callus induction and culture from explants of Erysimum scoparium in a growth regulator-free medium

Calli from cotyledon, hypocotyl and radicle explants of Erysimum scoparium (Brassicaceae) were induced and cultured using a MS medium without growth regulators. Calli obtained from cotyledon or hypocotyl explants showed a higher growth rate while radicle-derived calli exhibited poor growth. Cotyledon-derived calli were compact and green-colored while hypocotyl- and radicle-derived calli were friable and with creamy-green pigmentation. Histological analysis was carried out during culture and the development of abundant vascular elements and meristematic nodules were found. Subculture on a growth regulator-free medium during 10 months did not ecrease callus growth.     

Scientific societies fostering inclusivity through speaker diversity in annual meeting programming: a call to action

Scientific societies aiming to foster inclusion of scientists from underrepresented (UR) backgrounds among their membership often delegate primary responsibility for this goal to a diversity-focused committee. The National Science Foundation has funded the creation of the Alliance to Catalyze Change for Equity in STEM Success (ACCESS), a meta-organization bringing together representatives from several such STEM society committees to serve as a hub for a growing community of practice. Our goal is to coordinate efforts to advance inclusive practices by sharing experiences and making synergistic discoveries about what works. ACCESS has analyzed the approaches by which member societies have sought to ensure inclusivity through selection of annual meeting speakers. Here we discuss how inclusive speaker selection fosters better scientific environments for all and identify challenges and promising practices for societies striving to maximize inclusivity of speakers in their scientific programming.     

Selective enrichment of aromatic amino acid auxotrophs in Hansenula polymorpha.

Aromatic amino acid auxotrophs of the methanol-utilizing yeast Hansenula polymorpha were effectively selected by the use of nystatin and a medium that inhibits the growth of tyrosine auxotrophs. The procedure resulted in a frequency of aromatic auxotrophs of 2% of survivors and an enrichment of 20-fold. The new procedure also takes less time than traditional procedures. Of the auxotrophic mutants isolated, two-thirds required tyrosine and the remainder were tyrosine-phenylalanine double auxotrophs.