Commercial agrochemical applications in vineyards do not influence ant communities

Ants have been widely used as bioindicators for various terrestrial monitoring and assessment programs but are seldom considered in evaluation of nontarget pesticide effect. Much chemical assessment has been biased toward laboratory and bioassay testing for control of specific pest ant species. Several field studies that did explore the nontarget impacts of pesticides on ants have reported contradictory findings. To address the impact of chemical applications on ants, we tested the response of epigeal ant assemblages and community structure to three pesticide gradients (cumulative International Organization for Biological and Integrated Control toxicity rating, chlorpyrifos use rate, and sulfur use rate) in 19 vineyards. Ordination analyses using nonmetric multidimensional scaling detected community structures at species and genus levels, but the structures were not explained by any pesticide variables. There was no consistent pattern in species and genus percentage complementarities and ant assemblages along pesticide gradients. In contrast, ant community structure was influenced by the presence of shelterbelts near the sampling area. Reasons for the resilience of ants to pesticides are given and assessment at the colony level instead of workers abundance is suggested. The presence of Linepithema humile (Mayr) is emphasized.     

Effect of solar ultraviolet radiation on survival of krill larvae and copepods in Antarctic Ocean

The effect of solar ultraviolet radiation on the survival rate of Antarctic zooplankton was examined in February–March in 2002. We investigated survival rate of calyptopis larvae of Euphausia superba and late copepodite stages (IV and V) of large dominant calanoid species, Calanoides acutus and Calanus propinquus reared in quartz jars with three different radiation regimes (total radiation, exclusion of UVB, exclusion of UVA and UVB) and a dark control. The survival rates of the krill larvae decreased after 3 days from start of the experiment, being below 50% at 4 days in the treatments with total radiation and exclusion of UVB, although most individuals could survive until the end of the experiments in the treatments with exclusion of both UVA and UVB and dark control. The calanoid juveniles showed almost same pattern of survival curves as the krill larvae did, but survived slightly longer. Although >10% of surface UVA radiation at 340 and 380 nm penetrated down to 30 m, both C. acutus and C. propinquus were mostly distributed above 20 m. Surface swarm of the krill larvae can be often recognized in the previous studies. These results suggest that not only solar UVB but also UVA radiation potentially lower the survival rate of Antarctic zooplankton at depth less than 20 m.     

Secondhand Smoke Exposure and Maternal Action to Protect Children from Secondhand Smoke: Pre- and Post-Smokefree Legislation in Hong Kong

Background

Smokefree legislation may protect children from secondhand smoke (SHS) in the home from smoking parent(s). We examined the effect of the 2007 smokefree legislation on children’s exposure to SHS in the home and maternal action to protect children from SHS exposure in Hong Kong.

Methods

Families with a smoking father and a non-smoking mother were recruited from public clinics before (2005–2006, n = 333) and after the legislation (2007–2008, n = 742) which led to a major extension of smokefree places in Hong Kong. Main outcomes included children’s SHS exposure in the home, nicotine level in mothers’ and children’s hair and home environment, mothers’ action to protect children from SHS, and their support to the fathers to quit.

Results

Fewer mothers post-legislation reported children’s SHS exposure in the home (87.2% versus 29.3%, p<0.01), which was consistent with their hair nicotine levels (0.36ng/mg versus 0.04ng/mg, p<0.01). More mothers post-legislation in the last month took their children away from cigarette smoke (6.3% versus 92.2%; p<0.01) and advised fathers to quit over 3 times (8.3% versus 33.8%; p<0.01). No significant change was found in the content of smoking cessation advice and the proportion of mothers who took specific action to support the fathers to quit.

Conclusions

SHS exposure in the home decreased and maternal action to protect children from SHS increased after the 2007 smokefree legislation. Maternal support to fathers to quit showed moderate improvement. Cessation services for smokers and specific interventions for smoking families should be expanded together with smokefree legislation.     

Recent developments in antiviral agents against enterovirus 71 infection

Enterovirus 71 (EV-71) is the main etiological agent of hand, foot and mouth disease (HFMD). Recent EV-71 outbreaks in Asia-Pacific were not limited to mild HFMD, but were associated with severe neurological complications such as aseptic meningitis and brainstem encephalitis, which may lead to cardiopulmonary failure and death. The absence of licensed therapeutics for clinical use has intensified research into anti-EV-71 development. This review highlights the potential antiviral agents targeting EV-71 attachment, entry, uncoating, translation, polyprotein processing, virus-induced formation of membranous RNA replication complexes, and RNA-dependent RNA polymerase. The strategies for antiviral development include target-based synthetic compounds, anti-rhinovirus and poliovirus libraries screening, and natural compound libraries screening. Growing knowledge of the EV-71 life cycle will lead to successful development of antivirals. The continued effort to develop antiviral agents for treatment is crucial in the absence of a vaccine. The coupling of antivirals with an effective vaccine will accelerate eradication of the disease.     

Effects of a synthetic antitumoral catechin and its tyrosinase-processed product on the structural properties of phosphatidylcholine membranes

Catechin flavonoids are the main components of green tea extracts which present broad potential physiological activities. Several of their biological activities seem to affect membrane-dependent cellular processes and it is known that some catechins interact with phospholipid membranes. In this study we examine the interactions of a 3-O-(3,4,5-trimethoxybenzoyl)-(−)-catechin (TMCG), and its quinone methide (QM) activated product with 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) membranes by means of differential scanning calorimetry, X-ray diffraction, Fourier-Transform infrared spectroscopy and molecular dynamics simulation. We report that there are extensive interactions between TMCG and DPPC involving the perturbation of the thermotropic gel to liquid crystalline phase transition of the phospholipid, the decrease of bilayer thickness and the promotion of interdigitated gel phase, together with an increase of the hydrogen bonding pattern of the interfacial region of the bilayer. In contrast, QM shows a weak interaction with the phospholipid bilayer. Molecular dynamics simulation indicates that TMCG locates in the interior of the bilayer, while QM is found interacting with the surface of the membrane. The observations are interpreted in terms of the mechanism of membrane prodrug activation and the underlying membrane perturbations of the biological actions of natural catechins.     

Identification of recurrent regions of copy-number variants across multiple individuals

Background  

Algorithms and software for CNV detection have been developed, but they detect the CNV regions sample-by-sample with individual-specific breakpoints, while common CNV regions are likely to occur at the same genomic locations across different individuals in a homogenous population. Current algorithms to detect common CNV regions do not account for the varying reliability of the individual CNVs, typically reported as confidence scores by SNP-based CNV detection algorithms. General methodologies for identifying these recurrent regions, especially those directed at SNP arrays, are still needed.     

Study of monocyte membrane proteome perturbation during lipopolysaccharide‐induced tolerance using iTRAQ‐based quantitative proteomic approach

Human monocytes' exposure to low‐level lipopolysaccharide (LPS) induces temporary monocytic insensitivity to subsequent LPS challenge. The underlying mechanism of this phenomenon could have important clinical utilities in preventing and/or treating severe infections. In this study, we used an iTRAQ‐based quantitative proteomic approach to comprehensively characterize the membrane proteomes of monocytes before and after LPS exposure. We identified a total of 1651 proteins, of which 53.6% were membrane proteins. Ninety‐four percent of the proteins were quantified and 255 proteins were shown to be tightly regulated by LPS. Subcellular location analysis revealed organelle‐specific response to LPS exposure: more than 90% of identified mitochondrial membrane proteins were significant downregulated, whereas the majority of proteins from other organelles such as ER, Golgi and ribosome were upregulated. Moreover, we found that the expression of most receptors potentially involved in LPS signal pathway (CD14, toll‐like receptor 4, CD11/CD18 complex) were substantially decreased, while the expression of molecules involved in LPS neutralization were enhanced after LPS challenge. Together, these findings could be of significance in understanding the mechanism of LPS tolerance and provide values for designing new approaches for regulating monocytic responses in sepsis patients.