Discovery of potent,unsuspected sampling disparities for Malaise and Möricke traps,as shown for Neotropical Cryptini (Hymenoptera,Ichneumonidae)

Malaise and Möricke traps, universally used mostly to sample wasps and flies, are compared for the first time at genus level, focusing on Cryptini, one of the most diverse parasitoid taxa. Conclusions are supported by 10,706 man-hours of activities, 5,569 specimens from 20 Atlantic Forest and Amazon Forest localities, 4.81 Malaise trap-years and 89.09 Möricke trap-years. Substantial taxonomic and sexual biases were detected and quantified for Cryptini and for each of its studied genera. Möricke captured a proportion of Cryptini to other Ichenumonidae almost four times greater than Malaise. Most genera were captured mostly or exclusively by one of the traps only. Generally, Malaise collected 2.4 times more males than females, and 20% more species for males than females; Möricke yielded 2.4 times more females, and 2–4 times more species for females than males. The study scrutinizes and reaches beyond an allegedly known, but widely neglected problem. Data interpretation strongly suggests the necessity of sampling with both traps at once, under the risk that biodiversity investigations might otherwise continue to generate grossly biased results. Trap equivalence is discussed and quantified.     

Evolutionary patterns at the <Emphasis Type="Italic">RNase</Emphasis> based gametophytic self - incompatibility system in two divergent Rosaceae groups (Maloideae and <Emphasis Type="Italic">Prunus</Emphasis>)

Background  

Within Rosaceae, the RNase based gametophytic self-incompatibility (GSI) system has been studied at the molecular level in Maloideae and Prunus species that have been diverging for, at least, 32 million years. In order to understand RNase based GSI evolution within this family, comparative studies must be performed, using similar methodologies.     

Codon usage bias and the evolution of influenza A viruses. Codon Usage Biases of Influenza Virus

Background  

The influenza A virus is an important infectious cause of morbidity and mortality in humans and was responsible for 3 pandemics in the 20^th century. As the replication of the influenza virus is based on its host's machinery, codon usage of its viral genes might be subject to host selection pressures, especially after interspecies transmission. A better understanding of viral evolution and host adaptive responses might help control this disease.     

Root proliferation strategies and exploration of soil patchiness in arid communities

Soil patchiness is a key feature of arid rangelands. As root proliferation contributes to soil exploration and resource uptake, it is ecologically relevant to understand how species respond to soil heterogeneity and coexist. Campbell et al.'s influential 1991 hypothesis proposes that dominant species deploy root systems (scale) that maximize soil volume explored. Instead, subordinate species show accurate root systems that exclusively proliferate in nutrient‐rich patches (precision). After many experiments under controlled conditions, the generality of this hypothesis has been questioned but a field perspective is necessary to increase realism in the conceptual framework. We worked with a guild of perennial graminoid species inside a grazing exclosure in an arid Patagonian steppe, a model system for ecological studies in arid rangelands for four decades. We buried root traps in bare ground patches with sieved soil, with or without a pulse of nitrogen addition, to measure specific root biomass and precision at 6 and 18 months after burial. We also estimated scale (root density) in naturally established plants, and root decomposition in litter bags. Several species grew in root traps. Dominant species showed the highest root biomass (in both harvests) and scale. Subordinate species grew more frequently with nitrogen addition and showed lower biomass and scale. Similar total root biomass was found with and without nitrogen addition. Species differed in root decomposition, but correcting species biomass by decomposition did not change our conclusions. We did not find a relation between scale and precision, indicating that Campbell's hypothesis is probably not supported in this Patagonian steppe. Soil resource acquisition differences probably do not utterly explain the coexistence of dominant and subordinate species because the steppe is also affected by large herbivore grazing. We propose that root proliferation in this steppe is the result of the interaction between individual density in the community and specific root growth rates.     

The presence of Helicobacter pylori in the liver depends on the Th1, Th17 and Treg cytokine profile of the patient

The hypothesis that Helicobactermight be a risk factor for human liver diseases has arisen after the detection of Helicobacter DNA in hepatic tissue of patients with hepatobiliary diseases. Nevertheless, no explanation that justifies the presence of the bacterium in the human liver has been proposed. We evaluated the presence of Helicobacterin the liver of patients with hepatic diseases of different aetiologies. We prospectively evaluated 147 patients (106 with primary hepatic diseases and 41 with hepatic metastatic tumours) and 20 liver donors as controls. Helicobacter species were investigated in the liver by culture and specific 16S rDNA nested-polymerase chain reaction followed by sequencing. Serum and hepatic levels of representative cytokines of T regulatory cell, T helper (Th)1 and Th17 cell lineages were determined using enzyme linked immunosorbent assay. The data were evaluated using logistic models. Detection of Helicobacter pylori DNA in the liver was independently associated with hepatitis B virus/hepatitis C virus, pancreatic carcinoma and a cytokine pattern characterised by high interleukin (IL)-10, low/absent interferon-γ and decreased IL-17A concentrations (p < 10(-3)). The bacterial DNA was never detected in the liver of patients with alcoholic cirrhosis and autoimmune hepatitis that are associated with Th1/Th17 polarisation. H. pylori may be observed in the liver of patients with certain hepatic and pancreatic diseases, but this might depend on the patient cytokine profile.     

Genetic diversity and statistical parameters of 15 autosomal STR loci in the Pomeranian Subpopulation of Espirito Santo State,Brazil

Allelic frequencies and other population data analysis are reported for the 15 autosomal Short Tandem Repeats (STR) loci included in the PowerPlex^®16 kit (CSF1PO, D13S317, D16S539, D18S51, D21S11, D3S1358, D5S818, D7S820, D8S1179, FGA, Penta D, Penta E, TPOX, TH01 and vWA) in Pomeranian’s descendants from the Espirito Santo State (ES), Brazil, third largest population of Pomeranian’s descendants in the world. They chose the mountain region of the state for their preferred geographic location, and they have a very peculiar lifestyle with a selective mating behavior which has maintained their characteristics as a relatively pure subpopulation. Blood samples were obtained from 82 unrelated volunteers from 11 different cities of Espirito Santo State, where there are the Pomeranian’s descendants. All 15 loci analyzed showed Power of Discrimination (PD) values > 0.75. Except the TPOX locus, all analyzed loci were at Hardy–Weinberg equilibrium. This subpopulation has not yet been characterized for STR allelic frequencies used for forensic and genetic identification studies.     

Risk-Pooling and Herd Survival: An Agent-Based Model of a Maasai Gift-Giving System

We use agent-based modeling to study osotua, a gift giving system used by the Maasai of East Africa. Osotua’s literal meaning is “umbilical cord,” but it is used metaphorically to refer to a specific type of gift-giving relationship. Osotua relationships are characterized by respect, responsibility and restraint. Osotua partners ask each other for help only if they are in need and provide help only when asked and only if they are able. We hypothesize that under the ecologically volatile conditions in which Maasai pastoralists have traditionally lived, such a system is particularly suited to risk pooling. Here we explore whether osotua increases the viability of herds by comparing herd survivorship and stability under osotua rules to a) no exchange and b) probabilistic rules for requesting and giving livestock. Results from this model suggest that this gift-giving system can dramatically increase herd longevity through a limited pooling of risk.     

Activated inositol 1,4,5-trisphosphate receptors are modified by homogeneous Lys-48- and Lys-63-linked ubiquitin chains, but only Lys-48-linked chains are required for degradation

Inositol 1,4,5-trisphosphate (IP(3)) receptors (IP(3)Rs) are large, ubiquitously expressed, endoplasmic reticulum membrane proteins that form tetrameric IP(3) and Ca(2+)-gated Ca(2+) channels. Endogenous IP(3)Rs provide very appealing tools for studying the ubiquitin-proteasome pathway in intact mammalian cells because, upon activation, they are rapidly ubiquitinated and degraded. Using mass spectrometry, we previously examined the ubiquitination of IP(3)R1 in αT3-1 pituitary gonadotrophs and found that IP(3)R1 ubiquitination is highly complex, with receptors being modified at multiple sites by monoubiquitin and polyubiquitin chains formed through both Lys-48 and Lys-63 linkages (Sliter, D. A., Kubota, K., Kirkpatrick, D. S., Alzayady, K. J., Gygi, S. P., and Wojcikiewicz, R. J. H. (2008) J. Biol. Chem. 283, 35319-35328). Here, we have extended these studies to determine whether IP(3)R2 and IP(3)R3 are similarly modified and if ubiquitination is cell type-dependent. Using mass spectrometry and linkage-specific ubiquitin antibodies, we found that all IP(3)R types are subject to ubiquitination at approximately the same locations and that, independent of cell type, IP(3)Rs are modified by monoubiquitin and Lys-48- and Lys-63-linked ubiquitin chains, although in differing proportions. Remarkably, the attached Lys-48- and Lys-63-linked ubiquitin chains are homogeneous and are segregated to separate IP(3)R subunits, and Lys-48-linked ubiquitin chains, but not Lys-63-linked chains, are required for IP(3)R degradation. Together, these data provide unique insight into the complexities of ubiquitination of an endogenous ubiquitin-proteasome pathway substrate in unperturbed mammalian cells. Importantly, although Lys-48-linked ubiquitin chains appear to trigger proteasomal degradation, the presence of Lys-63-linked ubiquitin chains suggests that ubiquitination of IP(3)Rs may have physiological consequences beyond signaling for degradation.     

Insertion Sequence Element Single Nucleotide Polymorphism Typing Provides Insights into the Population Structure and Evolution of Mycobacterium ulcerans across Africa

Buruli ulcer is an indolent, slowly progressing necrotizing disease of the skin caused by infection with Mycobacterium ulcerans. In the present study, we applied a redesigned technique to a vast panel of M. ulcerans disease isolates and clinical samples originating from multiple African disease foci in order to (i) gain fundamental insights into the population structure and evolutionary history of the pathogen and (ii) disentangle the phylogeographic relationships within the genetically conserved cluster of African M. ulcerans. Our analyses identified 23 different African insertion sequence element single nucleotide polymorphism (ISE-SNP) types that dominate in different areas where Buruli ulcer is endemic. These ISE-SNP types appear to be the initial stages of clonal diversification from a common, possibly ancestral ISE-SNP type. ISE-SNP types were found unevenly distributed over the greater West African hydrological drainage basins. Our findings suggest that geographical barriers bordering the basins to some extent prevented bacterial gene flow between basins and that this resulted in independent focal transmission clusters associated with the hydrological drainage areas. Different phylogenetic methods yielded two well-supported sister clades within the African ISE-SNP types. The ISE-SNP types from the “pan-African clade” were found to be widespread throughout Africa, while the ISE-SNP types of the “Gabonese/Cameroonian clade” were much rarer and found in a more restricted area, which suggested that the latter clade evolved more recently. Additionally, the Gabonese/Cameroonian clade was found to form a strongly supported monophyletic group with Papua New Guinean ISE-SNP type 8, which is unrelated to other Southeast Asian ISE-SNP types.     

The Dose-Dependent Antioxidant Effects of Physical Exercise in the Hippocampus of Mice

Exercise increases both the consumption of oxygen and the production of reactive species in biological tissues, and this is counterbalanced by antioxidant adaptations to regular physical training. When the intensity of exercise fluctuates between mild and moderate, it improves the status of reduction–oxidation balance in the brain and induces neuroplasticity. However, intense exercise can oxidize the brain and impair neurological function. The effect of the frequency of exercise, which is an important factor in physical training, is still unknown. The effect of periodic exercise on biomarkers of oxidative stress in the hippocampus of mice was evaluated in this study. Mice were made to run on a treadmill for 8 weeks, two, three, or five times per week, and their hippocampi and quadriceps femoris muscles were then dissected. Biomarkers of oxidative damage were negatively correlated with the frequency of exercise and mitochondrial muscular activity, while the sulfhydryl contents were positively correlated with exercise frequency. A logistic analysis revealed a dose-dependent effect of exercise on these biomarkers. In summary, these results suggested that manipulating the frequency of physical exercise could induce antioxidant-related adaptations in the hippocampi of adult mice.