Shifts in aquatic macroinvertebrate biodiversity associated with the presence and size of an alien crayfish

To investigate the effects of Procambarus clarkii on macroinvertebrate diversity, we conducted a mesocosm experiment simulating small pools in rice field pads after the rice season. We hypothesized that crayfish predation would negatively impact macroinvertebrate diversity, and the magnitude of this impact should vary with the size of P. clarkii. We conducted a short-term mesocosm experiment to determine macroinvertebrate diversity in the presence of three size classes and in the absence of crayfish, as well as the diet composition of crayfish from the three size classes. At the end of the experiments, the diet of crayfish was composed of the most available taxa (Culicidae, Chironomus, Tanytarsini and Orthocladinae). These results also show evidence that, in confined areas, crayfish are important predators of major rice pests such as rice Chironominae larvae. Macroinvertebrate diversity was negatively affected by crayfish presence, but the effect was inversely proportional to crayfish size. The highest diversity index was obtained in the absence of P. clarkii, and juvenile crayfish significantly reduced macroinvertebrate diversity. Thus, the impact of P. clarkii on aquatic macroinvertebrates is size dependent and may be relevant in small pools formed in rice field pads from early autumn to late winter. Overall, our findings suggest that the negative effects of P. clarkii on macroinvertebrate diversity may be particularly strong in local natural assemblages confined to puddles of water or small ponds in wetland areas.     

Uptake and Function Studies of Maternal Milk-derived MicroRNAs

MicroRNAs (miRNAs) are important regulators of cell-autonomous gene expression that influence many biological processes. They are also released from cells and are present in virtually all body fluids, including blood, urine, saliva, sweat, and milk. The functional role of nutritionally obtained extracellular miRNAs is controversial, and irrefutable demonstration of exogenous miRNA uptake by cells and canonical miRNA function is still lacking. Here we show that miRNAs are present at high levels in the milk of lactating mice. To investigate intestinal uptake of miRNAs in newborn mice, we employed genetic models in which newborn miR-375 and miR-200c/141 knockout mice received milk from wild-type foster mothers. Analysis of the intestinal epithelium, blood, liver, and spleen revealed no evidence for miRNA uptake. miR-375 levels in hepatocytes were at the limit of detection and remained orders of magnitude below the threshold for target gene regulation (between 1000 and 10,000 copies/cell). Furthermore, our study revealed rapid degradation of milk miRNAs in intestinal fluid. Together, our results indicate a nutritional rather than gene-regulatory role of miRNAs in the milk of newborn mice.     

Mast cells and inflammation

Mast cells are well known for their role in allergic and anaphylactic reactions, as well as their involvement in acquired and innate immunity. Increasing evidence now implicates mast cells in inflammatory diseases where they are activated by non-allergic triggers, such as neuropeptides and cytokines, often exerting synergistic effects as in the case of IL-33 and neurotensin. Mast cells can also release pro-inflammatory mediators selectively without degranulation. In particular, IL-1 induces selective release of IL-6, while corticotropin-releasing hormone secreted under stress induces the release of vascular endothelial growth factor. Many inflammatory diseases involve mast cells in cross-talk with T cells, such as atopic dermatitis, psoriasis and multiple sclerosis, which all worsen by stress. How mast cell differential responses are regulated is still unresolved. Preliminary evidence suggests that mitochondrial function and dynamics control mast cell degranulation, but not selective release. Recent findings also indicate that mast cells have immunomodulatory properties. Understanding selective release of mediators could explain how mast cells participate in numerous diverse biologic processes, and how they exert both immunostimulatory and immunosuppressive actions. Unraveling selective mast cell secretion could also help develop unique mast cell inhibitors with novel therapeutic applications. This article is part of a Special Issue entitled: Mast cells in inflammation.     

The posibility of soil micromycetes produced the abscisic acid

The typical soil micromycetes Aspergillus niger and Cladosporium cladosporioides from the family moniliaceae were investigated with emphasis on production of ABA into the culture medium. The both fungi were cultivated in a static liquid Czapek — Dox medium and agar Czapek — Dox medium. Aspergillus niger and Cladosporium cladosporioides showed ability to produce ABA. Analytical detection of ABA from the culture medium was performed by TLC combinated with biotest and HPLC with spectroscopy.     

The Human-Baited Double Net Trap: An Alternative to Human Landing Catches for Collecting Outdoor Biting Mosquitoes in Lao PDR

Estimating the exposure of individuals to mosquito-borne diseases is a key measure used to evaluate the success of vector control operations. The gold standard is to use human landing catches where mosquitoes are collected off the exposed limbs of human collectors. This is however an unsatisfactory method since it potentially exposes individuals to a range of mosquito-borne diseases. In this study several sampling methods were compared to find a method that is representative of the human-biting rate outdoors, but which does not expose collectors to mosquito-borne infections. The sampling efficiency of four odour-baited traps were compared outdoors in rural Lao PDR; the human-baited double net (HDN) trap, CDC light trap, BG sentinel trap and Suna trap. Subsequently the HDN, the best performing trap, was compared directly with human landing catches (HLC), the ‘gold standard’, for estimating human-biting rates. HDNs collected 11–44 times more mosquitoes than the other traps, with the exception of the HLC. The HDN collected similar numbers of Anopheles (Rate Ratio, RR = 1.16, 95% Confidence Intervals, 95% CI = 0.61–2.20) and Culex mosquitoes (RR = 1.26, 95% CI = 0.74–2.17) as HLC, but under-estimated the numbers of Aedes albopictus (RR = 0.45, 95% CI = 0.27–0.77). Simpson’s index of diversity was 0.845 (95% CI 0.836–0.854) for the HDN trap and 0.778 (95% CI 0.769–0.787) for HLC, indicating that the HDN collected a greater diversity of mosquito species than HLC. Both HLC and HDN can distinguish between low and high biting rates and are crude ways to measure human-biting rate. The HDN is a simple and cheap method to estimate the human-biting rate outdoors without exposing collectors to mosquito bites.     

Conscientiousness is a predictor of diurnal preference

The relationship between diurnal preference, as measured by the Horne-Ostberg questionnaire, and quantifiable personality traits was investigated in 617 participants. A hierarchical multiple regression analysis demonstrated that out of the personality variables, conscientiousness was the single biggest predictor of diurnal preference (beta=0.246), after controlling for depression, sleep disorders, shift work, age, gender, and demographic characteristics. Morningness has previously been associated with physiological parameters of the circadian clock and with polymorphisms in circadian clock genes, suggesting the possibility that conscientiousness, too, may be linked to the same parameters.     

Structural variation in two human genomes mapped at single-nucleotide resolution by whole genome de novo assembly

Here we use whole-genome de novo assembly of second-generation sequencing reads to map structural variation (SV) in an Asian genome and an African genome. Our approach identifies small- and intermediate-size homozygous variants (1-50 kb) including insertions, deletions, inversions and their precise breakpoints, and in contrast to other methods, can resolve complex rearrangements. In total, we identified 277,243 SVs ranging in length from 1-23 kb. Validation using computational and experimental methods suggests that we achieve overall <6% false-positive rate and <10% false-negative rate in genomic regions that can be assembled, which outperforms other methods. Analysis of the SVs in the genomes of 106 individuals sequenced as part of the 1000 Genomes Project suggests that SVs account for a greater fraction of the diversity between individuals than do single-nucleotide polymorphisms (SNPs). These findings demonstrate that whole-genome de novo assembly is a feasible approach to deriving more comprehensive maps of genetic variation.     

Virus-derived anti-inflammatory proteins: potential therapeutics for cancer

Inflammatory responses now have a defined central role in cancer cell growth, invasion, and metastases. Anti-inflammatory proteins from viruses target key stages in immune response pathways and have potential as novel therapeutics for cancer, including highly potent virus-derived inhibitors of protease, chemokine, cytokine, and apoptotic cascades that have been identified. Serine proteases, in addition to their conventional roles in thrombosis, thrombolysis, and apoptotic pathways, are essential regulators of inflammation and are associated with developing cancers. Chemokines drive other inflammatory response pathways with central roles in cell invasion and activation as well as establishing the microenvironment of tumors, modulating immune cell infiltration, cancer cell proliferation, metastasis, and angiogenesis. This review focuses on the mechanisms of action and potential for application of viral immunomodulatory proteins as anticancer therapeutics.