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The objective of this study was to describe changes in the gene expression in the Chilean catfish, Trichomycterus areolatus, based on their geographic location within the Choapa River. Genes of choice included those that are biomarkers of exposure to metals, oxidative stress, and endocrine disruption. Male and female T. areolatus were sampled from four sites in January 2015 differently impacted by human activities. In males, but not females, hepatic gene expression of heat shock protein (HSP70) and cytochrome P450 1A (CYP1A) were significantly elevated at the site adjacent to the small city of Salamanca, relative to the other sites. In females, hepatic HSP70, the aryl hydrocarbon receptor (AHR), and the estrogen responsive genes, vitellogenin (VTG) and estrogen receptor alpha (ERα), were significantly lower at the site located furthest downstream. A similar downstream pattern of lower expression levels also was found in ovarian tissue for the genes, HSP70 and ERα. Gill gene expression showed a unique pattern in females as levels of metallothionein were elevated at the site furthest downstream. While analytical chemistry of water samples provided limited evidence of agrichemical contamination, the gene expression data are consistent with an exposure to agrichemicals and metals. T. areolatus may be a valuable sentinel organism and its use as a bioindicator species in some rivers within Chile can provide considerable insight, particularly in situations analytical chemistry is limited by environmental constraints.

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Water quality management is an ongoing struggle for many locations worldwide. Current testing of water supplies can be time-consuming, expensive, and lack sensitivity. This study describes an alternative, easy-to-use, and inexpensive method to water sampling and testing at remote locations. This method was employed to detect a number of intestinal pathogens in various locations of Lima, Peru. A total of 34 PCR primer pairs were tested for specificity and high-yield amplification for 12 different pathogens using known DNA templates. Select primers for each pathogen were then tested for minimum detection limits of DNA. Water samples were collected from 22 locations. PCR was used to detect the presence of a pathogen, virulence factors, or differentiate between pathogenic species. In 22 water samples, cholera toxin gene was detected in 4.5% of samples, C. perfringens DNA was detected in 50% of samples, E. histolytica DNA was detected in 54.5% of samples, Giardia intestinalis DNA was detected in 4.5% of samples, Leptospira spp. DNA was detected in 29% of samples, and T. gondii DNA was detected in 31.8% of samples. DNA from three pathogens, C. perfringens, E. histolytica, and T. gondii, were found in residential samples, which accounted for 10 out of 22 samples.

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Trichomycterus areolatus is an endemic species of pencil catfish that inhabits the riffles and rapids of many freshwater ecosystems of Chile. Despite its unique adaptation to Chile's high gradient watersheds and therefore potential application in the investigation of ecosystem integrity and environmental contamination, relatively little is known regarding the molecular biology of this environmental sentinel. Here, we detail the assembly of the Trichomycterus areolatus transcriptome, a molecular resource for the study of this organism and its molecular response to the environment. RNA-Seq reads were obtained by next-generation sequencing with an Illumina® platform and processed using PRINSEQ. The transcriptome assembly was performed using TRINITY assembler. Transcriptome validation was performed by functional characterization with KOG, KEGG, and GO analyses. Additionally, differential expression analysis highlights sex-specific expression patterns, and a list of endocrine and oxidative stress related transcripts are included.

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This study aims to explore the different connotations and potential offensiveness of ten mechanistic labels in newly referred Mexican patients with rheumatic symptoms as well as in Mexican and Canadian rheumatologists. Patients with musculoskeletal complaints newly referred for a rheumatology assessment were interviewed consecutively before they saw the rheumatologist. Patients were asked to choose one of nine feelings provoked by ten different illness mechanism labels. Rheumatologists gave a medical diagnosis after seeing the patients. Mexican and Canadian rheumatologists were invited to answer a structured questionnaire about their feelings at the moment they identified each of the ten different provided scenarios. Patients' and rheumatologists' feelings were classified as "offended" or "nonoffended." The "offensive score" was used to calculate a "number needed to offend" (NNO). One hundred and fifty patients were included. Inherited, immunological, and inflammatory labels had the fewest negative connotations (NNOs 17, 12, and 14, respectively), and psychological, functional, idiopathic, and sleep disturbance labels had the most (NNO 2 and 3, respectively). Functional labels were almost four times more offensive than organic labels. Stratified by rheumatologist diagnosis, patients with functional disorders were more accepting of organic-based mechanistic labels. A higher potential to offend was observed when patients with functional somatic conditions were given functional mechanistic labels (NNOs 1 to 4). The survey was completed by 186 Mexican rheumatologists and 71 Canadian rheumatologists. Primarily functional disorders such as somatization and anxiety had a high potential to evoke offensive feelings (NNOs 3 to 7). No significant differences in the NNO were found between Mexican and Canadian rheumatologists. Getting or giving mechanistic/explanatory labels is emotional. Both patients and rheumatologists experienced offended feelings with functional or idiopathic labels.

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We used stable isotope ratios to determine the metabolic routing fraction of carbon and nitrogen in feathers in addition to faecal analysis to estimate diet overlap of six sympatric species of manakins in the eastern lowland forest of Ecuador. Collectively, all species varied from-23.7 to-32.7 ‰ for δ(13)C, and from 6.0 to 9.9‰ for δ(15)N, with Machaeropterus regulus showing isotopic differences from the other species. We developed a mixing model that explicitly addresses the routing of carbon and nitrogen to feathers. Interestingly, these results suggest a higher proportion of nitrogen and carbon derived from insects than anticipated based on feeding observations and faecal analysis. A concentration-dependent mixing isotopic model was also used to look at dietary proportions. While larvae and arachnids had higher δ(15)N values, these two groups may also be preferred prey of manakins and may be more assimilated into tissues, leading to a potential overestimation of the contribution to diet. This study supports the finding that manakin species, previously thought be primarily frugivorous, contain a significant amount of arthropods in their diet.

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Great earthquakes have repeatedly occurred on the plate interface in a few shallow-dipping subduction zones where the subducting and overriding plates are strongly locked. Silent earthquakes (or slow slip events) were recently discovered at the down-dip extension of the locked zone and interact with the earthquake cycle. Here, we show that locally observed converted SP arrivals and teleseismic underside reflections that sample the top of the subducting plate in southern Mexico reveal that the ultra-slow velocity layer (USL) varies spatially (3 to 5 kilometers, with an S-wave velocity of approximately 2.0 to 2.7 kilometers per second). Most slow slip patches coincide with the presence of the USL, and they are bounded by the absence of the USL. The extent of the USL delineates the zone of transitional frictional behavior.

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Bacillus thuringiensis Cry1Ac toxin is 100 times less toxic than Cry1C to Mamestra brassicae. An R(423)S mutation abolishes Cry1Ac toxin proteolysis in M. brassicae gut juice but does not increase its toxicity to this insect. The CryAAC hybrid toxin (1Ac/1Ac/1Ca) is toxic to M. brassicae but is susceptible to gut protease digestion at the R(423) residue. Accordingly we have investigated the effect of the R(423)S mutation in CryAAC on its toxicity for M. brassicae and Pieris brassicae. Bioassays demonstrated that the R(423)S mutation slightly increased the toxicity of CryAAC for M. brassicae by having a significantly inhibitory effect on the growth of surviving larvae. The mutant hybrid was still highly toxic to P. brassicae. Features of CryAACR(423)S such as, (1) stability in M. brassicae gut juice and (2) crystal solubility were investigated. Computer simulations suggest that a possible major increase in flexibility in the CryAAC loop beta7/beta8 (G(391)-P(397)) caused by the R(423)S substitution could be a reason for the increase in M. brassicae toxicity.

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OBJECTIVE: To test the hypothesis that oxidative stress signaling contributes to post-transplant endothelial dysfunction and hypertension in pediatric post-transplant hypertension. STUDY DESIGN: This study evaluated in 16 pediatric renal transplant patients, divided in two groups based on the presence of post-transplant hypertension, the oxidative stress status measuring the gene expression (reverse transcription-polymerase chain reaction) of two major oxidative stress-related proteins, p22(phox) and heme oxygenase-1 (HO-1). Total plasma antioxidant power (ELISA) was also evaluated. RESULTS: Mononuclear cell p22(phox) gene expression was higher in hypertensive patients compared with the normotensive group (0.91 +/- 0.06 vs 0.79 +/- 0.08 densitometric units, P < .02), whereas HO-1 RNA production and total plasma antioxidant power were higher in the normotensive group (0.38 +/- 0.04 vs 0.20 +/- 0.11 d.u., P < .006, and 1189.35 +/- 145.75 vs 772.71 +/- 196.03 micromol/L, P < .01, respectively). CONCLUSIONS: Oxidative stress is associated with post-transplant hypertension in hypertensive pediatric kidney-transplant patients, who therefore are at risk of oxidative stress-induced organ damage. They might benefit from treatments addressing not only hypertension but also oxidant-related complications.

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