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Growing concern over rapid species declines and extinctions has led to considerable interest in the role of biodiversity for maintaining ecological processes. However, the loss of particular species has more pronounced effects on ecosystem services than others, highlighting the importance of key functional species traits and their relationships to ecosystem functioning. Human‐induced disturbances, such as species invasions, land use changes, or abiotic changes, appear to disproportionally impact larger species rather than smaller ones. The loss of large‐bodied species in the community diminishes key ecosystem services like seed dispersal, pest control, pollination and decomposition.Here, we use carrion, a nutrient‐rich ephemeral resource, to test the hypotheses that ants positively affect decomposition rates and that their role in the necrophilous community—as predator or decomposer—is mediated by body size. We further investigate the relative contribution of maggots versus ants to biomass decomposition.Our results show that ants contributed positively to the decomposition process. Moreover, decomposition was shaped by an intricate interplay between competition and predation among the guild of decomposer insects. As predicted, larger ants show a double action in increasing decomposition rate and predating on maggots, while small ants are rather inefficient decomposers and did not act as predators on other decomposer species.Our study shows that differentiating key taxonomic groups in function of their body size is key to untangle the diversity and directions of the various roles they play within complex ecological processes. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

The authors aim to develop siRNA therapeutics for cancer that can be administered systemically to target tumors and retard their growth. The efficacy of systemic delivery of siRNA to tumors with nanoparticles based on lipids or polymers is often compromised by their rapid clearance from the circulation by the liver. Here, multifunctional cationic and anionic siRNA nanoparticle formulations are described, termed receptor‐targeted nanocomplexes (RTNs), that comprise peptides for siRNA packaging into nanoparticles and receptor‐mediated cell uptake, together with lipids that confer nanoparticles with stealth properties to enhance stability in the circulation, and fusogenic properties to enhance endosomal release within the cell. Intravenous administration of RTNs in mice leads to predominant accumulation in xenograft tumors, with very little detected in the liver, lung, or spleen. Although non‐targeted RTNs also enter the tumor, cell uptake appears to be RGD peptide‐dependent indicating integrin‐mediated uptake. RTNs with siRNA against MYCN (a member of the Myc family of transcription factors) in mice with MYCN‐amplified neuroblastoma tumors show significant retardation of xenograft tumor growth and enhanced survival. This study shows that RTN formulations can achieve specific tumor‐targeting, with minimal clearance by the liver and so enable delivery of tumor‐targeted siRNA therapeutics. [ABSTRACT FROM AUTHOR]

A 22 month old child with thalassaemia major received unrelated umbilical cord blood transplantation. She was born to mother of HBsAg carrier and received hepatitis B immunoglobulin at birth and hepatitis B vaccination. She was HBsAg negative and anti-HBs positive before transplantation. After transplant, she was taken care by her mother and found to be HBsAg positive at 2 year post-transplant. Genotyping of the mother's and child's HBV status confirmed to be of same genotype and demonstrated horizontal transmission in post-transplant setting. Passive immunization of HBV may be considered in early post-transplant phase to prevent horizontal transmission of HBV, and antiviral treatment of the carer should be offered to prevent transmission of infection to immunocompromised child. [ABSTRACT FROM AUTHOR]

Sweet potato (Ipomoea batatas [L.] Lam.) is an important subsistence crop in Sub‐Saharan Africa, yet as for many crops, yield can be severely impacted by drought stress. Understanding the genetic mechanisms that control drought tolerance can facilitate the development of drought‐tolerant sweet potato cultivars. Here, we report an expression profiling study using the US‐bred cultivar, Beauregard, and a Ugandan landrace, Tanzania, treated with polyethylene glycol (PEG) to simulate drought and sampled at 24 and 48 hr after stress. At each time‐point, between 4,000 to 6,000 genes in leaf tissue were differentially expressed in each cultivar. Approximately half of these differentially expressed genes were common between the two cultivars and were enriched for Gene Ontology terms associated with drought response. Three hundred orthologs of drought tolerance genes reported in model species were identified in the Ipomoea trifida reference genome, of which 122 were differentially expressed under at least one experimental condition, constituting a list of drought tolerance candidate genes. A subset of genes was differentially regulated between Beauregard and Tanzania, representing genotype‐specific responses to drought stress. The data analyzed and reported here provide a resource for geneticists and breeders toward identifying and utilizing drought tolerance genes in sweet potato. [ABSTRACT FROM AUTHOR]

1. The present study was designed to test the hypotheses whether platelet degranulation across the coronary bed is detectable during non-ischaemic periods in patients with vasospastic angina (VSA) and whether the exogenous nitric oxide (NO) donor nitroglycerin (GTN) is able to modify platelet degranulation, reflecting an impaired endothelial production of NO. 2. We studied 13 patients with VSA and 10 controls. The time course of coronary sinus (CS) plasma 5-hydroxytryptamine (5-HT) levels was evaluated every 4 h before and after intravenous infusion of GTN over a period of 40 h. Coronary sinus plasma 5-HT levels were significantly higher at any measured time point in patients with VSA compared with control and were significantly decreased in patients with VSA following treatment with GTN, but not in controls. Femoral artery plasma 5-HT levels remained almost constant throughout the study. The ratio of CS:aorta 6-keto-prostaglandin F1 alpha was significantly and inversely correlated with the transcardiac plasma 5-HT difference only in patients with VSA (r = -0.68; P < 0.02; n = 13). 3. The time course of CS 5-HT levels confirmed significant platelet degranulation across the coronary bed supplied by the spasming artery in patients with VSA and this was modified by GTN. The present data suggest that platelet degranulation occurs during non-ischaemic periods in patients with VSA and that prostacyclin biosynthesis may be a compensatory response to an impaired endothelial release of NO, limiting the degree of the effects of platelet degranulation.