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Characterization of the diversity of filamentous fungi and protists in the Richmond Mine at Iron Mountain, Calif by utilizing both beta-tubulin and 18S rRNA gene sequence phylogenetic analyses is reported. The development of 18S rRNA fungal probes helped in identifying and studying the distribution of lineages of morphologically indistinguishable fungi in environmental samples. Three isolates with 18s rRNA genes that are closely related to the Dothideomycetes clones were obtained and the name 'Acidomyces richmondensis' is suggested for the isolates on the basis of their genus-level phylogenetic divergence and environmental adaptation.

Research has been conducted on protist endosymbionts from the acid mine drainage. The authors have investigated these endosymbionts via the use of culture-independent approaches.

Background: High consumption of low- and non-fat dairy products improves vascular dysfunction associated with elevated arterial blood pressure (BP). Currently, it is unknown if conventional full-fat dairy products improve vascular functions.Objectives: To determine if adding whole milk and full-fat dairy products to the normal routine diet improves vascular function in adults with elevated BP.Design: Sixty adults (age ± SEM; 58 ± 2 years) with elevated BP (systolic/diastolic; 120-159/ < 99 mmHg) were randomized into a controlled crossover intervention trial consisting of two 4-week dietary periods. The high dairy condition consisted of adding four daily servings of whole milk or full-fat dairy products to the normal diet and eliminated all dairy intake during the control (no dairy) condition. A 2-week washout period separated the dietary conditions.Results: Carotid-femoral pulse wave velocity (cfPWV) did not differ significantly between high dairy (11.3 ± 0.3 versus 10.9 ± 0.3 m/sec) and no dairy conditions (11.2 ± 0.3 versus 11.0 ± 0.3 m/sec). The results were consistent when ultrasound-derived vascular distension measures (arterial compliance, beta-stiffness index, and elastic modulus) were evaluated. Cardiovagal baroreceptor sensitivity (via Valsalva maneuver) demonstrated no significant difference for either dietary condition. Brachial arterial flow-mediated dilation (FMD) did not differ significantly during the high dairy (5.7 ± 0.5 versus 5.4 ± 0.6%) and no dairy conditions (6.5 ± 0.5 versus 5.6 ± 0.6%).Conclusions: The solitary addition of whole milk and full-fat dairy products has no effect on subclinical vascular function in adults with elevated BP. [ABSTRACT FROM AUTHOR]

Chronic pain is a debilitating condition that affects many people. Currently, there is no single treatment known to cure or assure relief from chronic pain. Accordingly, the management of patients' discomfort is an integral part of treating chronic pain. Such treatment, however, is not effective for many patients. We investigated whether mirthful laughter provided by comic relief can influence pain tolerance and muscle soreness in young healthy participants. Forty participants underwent a randomized controlled cross-over designed experiment. Each participant was exposed to a comedy video eliciting mirthful laughter and an uninteresting documentary. Delayed onset muscle soreness was induced in one leg at a time by eccentric exercise. Pain tolerance was tested using blunt force application and assessed subjectively using a visual analog scale. Watching the comedy video elicited a significantly greater irregular breathing pattern compared with watching the documentary video (p < 0.001). After watching the comedy, the participants' positive affect was increased (Δ2 ± 1) while it was largely decreased (Δ-11 ± 2) after watching the documentary video (p < 0.001). Pain tolerance was decreased by 17 ± 5 N after viewing the documentary video (p < 0.001), but did not change significantly after watching the comedy. Thirty minutes of watching a comedy eliciting laughter favorably influenced pain tolerance in healthy humans. #NCT02896075. [ABSTRACT FROM AUTHOR]

Metagenomics of marine sediments has uncovered a broad diversity of new uncultured taxa, and provided the insights into their metabolic capabilities. Here, we detected microbial lineages from a sediment core near the Jiulong methane reef of the northern South China Sea (at 1100 m depth). Assembly and binning of the metagenomes resulted in 11 genomes (>85% complete) that represented nine distinct phyla including candidate phyla TA06 and LCP-89, Lokiarchaeota, Heimdallarchaeota, and a newly described globally distributed phylum (B38). The genome of LCP-89 has pathways for nitrate, selenate and sulfate reduction, suggesting that they may be involved in mediating these important processes. The B38 is able to participate in the cycling of hydrogen and selenocompounds. Many of these uncultured microbes may also be capable of autotrophic CO2 fixation, as exemplified by identification of the Wood-Ljungdahl (W-L) pathway. The carbohydrate degradation, W-L pathway, Rnf-dependent energy conservation and Ni/Fe hydrogenases were detected in the transcriptomes of these novel members. Characterizations of these new lineages provide insights to the undescribed branches in the tree of life. IMPORTANCE Sedimentary microorganisms in the South China Sea (SCS) remain largely unknown, due to the complexity of sediment communities impacted by continent rifting and extension. Distinct geochemical environments may breed special microbial communities including microbes that are still enigmatic. Functional inference of their metabolisms and transcriptional activity provided the insights in the ecological roles and substrate-based interactivity of these uncultured Archaea and Bacteria. These microorganisms play different roles in utilizing inorganic carbon and scavenging diverse organic compounds to involve in deep-sea carbon cycle. The genomes recovered here contributed undescribed species to the tree of life and laid a foundation for future study on these novel phyla persisting in marginal sediments of the SCS. [ABSTRACT FROM AUTHOR]

We determined whether the incidence of injuries would increase with advancing age and whether the participation in cross-training would be related to a decreased rate of injuries and healthcare costs in Masters swimmers. A total of 499 swimmers (55 ± 14 years of age) belonging to US Masters Swimming completed a comprehensive questionnaire that included questions regarding their medical history as well as their training history. In average, swimmers had been training for 13 ± 12 years, and 35, 40, and 47 % participated in running, cycling, and dryland resistance training, respectively. According to the logistic regression, prevalence of injuries increased significantly but modestly with advancing age (p < 0.05). Linear regression analysis showed that for every 1 month increase in the length of injury, healthcare costs increased by 7.4 % (p < 0.05). Linear regression and logistic regression analyses determined that overall volume of swimming training was not related to age or incidence of injuries, respectively. Multinomial logistic regression analyses using age and sex as predictors demonstrated that the odds of reporting a swim-related injury were significantly lower for individuals who participated in any number of cross-training activities compared with those who do not cross-train (p < 0.05). Regular participation in any cross-training modality was inversely related to age (p < 0.05). We concluded that the diversification of the overall training program by incorporating cross-training may be an important strategy to reduce sport-specific injuries among Masters athletes. [ABSTRACT FROM AUTHOR]

The Zn(ii)–(Imidazole(ate))n coordination motif occurs in numerous biochemical systems, including carbonic anhydrase and the matrix metalloproteinases (MMPs). Additionally, it has been used in synthetic materials, such as the zinc-based zeolitic imidazolate framework (ZIF) structures. Zinc centers in these systems typically act as Lewis acids that form complexes with small molecules, such as H2O, which is activated catalytically toward a number of important and useful hydrolysis reactions. The results reported herein from density functional theory (M05-2X) and ab initio (MP2 and CCSD(T)) calculations demonstrate that both the coordination number and the molecular geometry have a sizable impact on the binding strength, deprotonation energy, and acidity of the Zn(ii) coordinated water. Through a series of quantum mechanical calculations on [(ImH)nZn–OH2]2+ complexes (n = 1–5), both the solution-phase pKa and the gas-phase proton dissociation energy significantly increase as n increases. While this should not be too surprising, the Zn–OH2 bond dissociation energies and bond lengths don’t necessarily undergo a concurrent decrease, and therefore would be of limited use as a prediction tool regarding Zn–OH2 acidity. In an effort to dissect the impacts of coordination number and molecular geometry on these thermodynamic parameters, we performed constrained geometry optimizations on the three- (n = 2) and four-coordinate (n = 3) complexes. These calculations surprisingly reveal a marked impact on the pKa and proton dissociation energy of the coordinated water, upon exclusive changes in the Zn(ii) coordination geometry, whether in the gas-phase or in aqueous solution. We discuss the relevance of these results to the catalytic peptide hydrolysis mechanism of the MMPs and possible implications for catalytic activity within or on the surfaces of ZIFs. [ABSTRACT FROM AUTHOR]

The Deepwater Horizon (DWH) blowout resulted in the deposition to the seafloor of up to 4.9% of 200 million gallons of oil released into the Gulf of Mexico. The petroleum hydrocarbon concentrations near the wellhead were high immediately after the spill, but returned to background levels a few years after the spill. Microbial communities in the seafloor are thought to be responsible for the degradation of hydrocarbons, however, our knowledge is primarily based upon gene diversity surveys and hydrocarbon concentration in field sediment samples. Here, we investigated the oil degradation potential and changes in bacterial community by amending seafloor sediment collected near the DWH site with crude oil and both oil and Corexit dispersant. Polycyclic aromatic hydrocarbons were rapidly degraded during the first 30 days of incubation, while alkanes were degraded more slowly. With the degradation of hydrocarbons, the relative abundances of Colwelliaceae, Alteromonadaceae, Methylococales, Alcanivorax, Bacteriovorax, and Phaeobacter increased remarkably. However, the abundances of oil-degrading bacteria changed with oil chemistry. Colwelliaceae decreased with increasing oil degradation, whereas Alcanivorax and Methylococcales increased considerably. We assembled seven genomes from the metagenome, including ones belonging to Colwellia, Alteromonadaceae, Rhodobacteraceae, the newly reported genus Woeseia, and candidate phylum NC10, all of which possess a repertoire of genes for hydrocarbon degradation. Moreover, genes related to hydrocarbon degradation were highly enriched in the oiled treatment, suggesting that the hydrocarbons were biodegraded, and that the indigenous microflora have a remarkable potential for the natural attenuation of spilled oil in the deep-sea surface sediment. [ABSTRACT FROM AUTHOR]

Sediment runoff has been cited as a major contributor to the declining health of the Great Barrier Reef (GBR), however, climate and land use drivers have not been jointly evaluated. This study used alluvial archives from fluvial benches in two tributaries of the Upper Burdekin catchment together with the best available land use history and climate proxy records to provide insights into the timing of depositional events in this region over the past 500 years. This study suggests that mining and the increased runoff variability in the latter half of the nineteenth century are the likely sources of the original excess sediment that was used to build the bench features in these catchments. Grazing also contributed to increased bench sedimentation prior to 1900, however, the contribution of grazing was likely more significant in the second half of the 20th century, and continues to be a dominant land use contributor today. [ABSTRACT FROM AUTHOR]

Small acidophilic archaea belonging to Micrarchaeota and Parvarchaeota phyla are known to physically interact with some Thermoplasmatales members in nature. However, due to a lack of cultivation and limited genomes on hand, their biodiversity, metabolisms, and physiologies remain largely unresolved. Here, we obtained 39 genomes from acid mine drainage (AMD) and hot spring environments around the world. 16S rRNA gene based analyses revealed that Parvarchaeota were only detected in AMD and hot spring habitats, while Micrarchaeota were also detected in others including soil, peat, hypersaline mat, and freshwater, suggesting a considerable higher diversity and broader than expected habitat distribution for this phylum. Despite their small genomes (0.64-1.08 Mb), these archaea may contribute to carbon and nitrogen cycling by degrading multiple saccharides and proteins, and produce ATP via aerobic respiration and fermentation. Additionally, we identified several syntenic genes with homology to those involved in iron oxidation in six Parvarchaeota genomes, suggesting their potential role in iron cycling. However, both phyla lack biosynthetic pathways for amino acids and nucleotides, suggesting that they likely scavenge these biomolecules from the environment and/or other community members. Moreover, low-oxygen enrichments in laboratory confirmed our speculation that both phyla are microaerobic/anaerobic, based on several specific genes identified in them. Furthermore, phylogenetic analyses provide insights into the close evolutionary history of energy related functionalities between both phyla with Thermoplasmatales. These results expand our understanding of these elusive archaea by revealing their involvement in carbon, nitrogen, and iron cycling, and suggest their potential interactions with Thermoplasmatales on genomic scale. [ABSTRACT FROM AUTHOR]