First insights into the vertical habitat use of the whitespotted eagle ray Aetobatus narinari revealed by pop-up satellite archival tags

The whitespotted eagle ray Aetobatus narinari is a tropical to warm-temperate benthopelagic batoid that ranges widely throughout the western Atlantic Ocean. Despite conservation concerns for the species, its vertical habitat use and diving behaviour remain unknown. Patterns and drivers in the depth distribution of A. narinari were investigated at two separate locations, the western North Atlantic (Islands of Bermuda) and the eastern Gulf of Mexico (Sarasota, Florida, U.S.A.). Between 2010 and 2014, seven pop-up satellite archival tags were attached to A. narinari using three methods: a through-tail suture, an external tail-band and through-wing attachment. Retention time ranged from 0 to 180 days, with tags attached via the through-tail method retained longest. Tagged rays spent the majority of time (82.85 ± 12.17% S.D.) within the upper 10 m of the water column and, with one exception, no rays travelled deeper than ~26 m. One Bermuda ray recorded a maximum depth of 50.5 m, suggesting that these animals make excursions off the fore-reef slope of the Bermuda Platform. Individuals occupied deeper depths (7.42 ± 3.99 m S.D.) during the day versus night (4.90 ± 2.89 m S.D.), which may be explained by foraging and/or predator avoidance. Each individual experienced a significant difference in depth and temperature distributions over the diel cycle. There was evidence that mean hourly depth was best described by location and individual variation using a generalized additive mixed model approach. This is the first study to compare depth distributions of A. narinari from different locations and describe the thermal habitat for this species. Our study highlights the importance of region in describing A. narinari depth use, which may be relevant when developing management plans, whilst demonstrating that diel patterns appear to hold across individuals.     

Caveolins and intracellular calcium regulation in human airway smooth muscle

Regulation of intracellular Ca(2+) concentration ([Ca(2+)](i)) is a key factor in airway smooth muscle (ASM) tone. In vascular smooth muscle, specialized membrane microdomains (caveolae) expressing the scaffolding protein caveolin-1 are thought to facilitate cellular signal transduction. In human ASM cells, we tested the hypothesis that caveolae mediate Ca(2+) responses to agonist stimulation. Fluorescence immunocytochemistry with confocal microscopy, as well as Western blot analysis, was used to determine that agonist receptors (M(3) muscarinic, bradykinin, and histamine) and store-operated Ca(2+) entry (SOCE)-regulatory mechanisms colocalize with caveolin-1. Although caveolin-2 coexpressed with caveolin-1, caveolin-3 was absent. In fura 2-loaded ASM cells, [Ca(2+)](i) responses to 1 microM ACh, 10 microM histamine, and 10 nM bradykinin, as well as SOCE, were attenuated (each to a different extent) after disruption of caveolae by the cholesterol-chelating drug methyl-beta-cyclodextrin. Transfection of ASM cells with 50 nM caveolin-1 small interfering RNA significantly weakened caveolin-1 expression and blunted [Ca(2+)](i) responses to bradykinin and histamine, as well as SOCE, but the response to ACh was less intense. These results indicate that caveolae are present in ASM and that caveolin-1 contributes to regulation of [Ca(2+)](i) responses to agonist.     

Engineering clinically relevant volumes of vascularized bone

Vascularization remains one of the most important challenges that must be overcome for tissue engineering to be consistently implemented for reconstruction of large volume bone defects. An extensive vascular network is needed for transport of nutrients, waste and progenitor cells required for remodelling and repair. A variety of tissue engineering strategies have been investigated in an attempt to vascularize tissues, including those applying cells, soluble factor delivery strategies, novel design and optimization of bio‐active materials, vascular assembly pre‐implantation and surgical techniques. However, many of these strategies face substantial barriers that must be overcome prior to their ultimate translation into clinical application. In this review recent progress in engineering vascularized bone will be presented with an emphasis on clinical feasibility.     

A direct,ratiometric, and quantitative MALDI–MS assay for protein methyltransferases and acetyltransferases

Protein methylation and acetylation play important roles in biological processes, and misregulation of these modifications is involved in various diseases. Therefore, it is critical to understand the activities of the enzymes responsible for these modifications. Herein we describe a sensitive method for ratiometric quantification of methylated and acetylated peptides via MALDI–MS by direct spotting of enzymatic methylation and acetylation reaction mixtures without tedious purification procedures. The quantifiable detection limit for peptides with our method is approximately 10 fmol. This is achieved by increasing the signal-to-noise ratio through the addition of NH₄H₂PO₄ to the matrix solution and reduction of the matrix α-cyanohydroxycinnamic acid concentration to 2 mg/ml. We have demonstrated the application of this method in enzyme kinetic analysis and inhibition studies. The unique feature of this method is the simultaneous quantification of multiple peptide species for investigation of processivity mechanisms. Its wide buffer compatibility makes it possible to be adapted to investigate the activity of any protein methyltransferase or acetyltransferase.     

Flow regulation of collecting duct endothelin-1 production

Collecting duct (CD) endothelin-1 (ET-1) is an important autocrine inhibitor of CD Na(+) reabsorption. Salt loading is thought to increase CD ET-1 production; however, definitive evidence of this, as well as understanding of the mechanisms transducing this effect, is lacking. Tubule fluid flow increases in response to Na(+) loading; hence, we studied flow modulation of CD ET-1 production. Three days of a high-salt diet increased mouse and rat inner medullary CD (IMCD) ET-1 mRNA expression. Acute furosemide infusion increased urinary ET-1 excretion in anesthetized rats. Primary cultures of mouse or rat IMCD detached in response to flow using a closed perfusion chamber, consequently a CD cell line (mpkCCDcl4) was examined. Flow increased ET-1 mRNA at shear stress rates exceeding 1 dyne/cm(2), with the maximal effect seen between 2 and 10 dyne/cm(2). Induction of ET-1 mRNA was first evident after 1 h, and most apparent after 2 h, of flow. Inhibition of calmodulin or dihydropyridine-sensitive Ca(2+) channels did not alter the flow response; however, chelation of intracellular Ca(2+) or removal of extracellular Ca(2+) largely prevented flow-stimulated ET-1 mRNA accumulation. Downregulation of protein kinase C (PKC) using phorbol 12-myristate 13-acetate, or PKC inhibition with calphostin C, markedly reduced flow-stimulated ET-1 mRNA levels. Flow-stimulated ET-1 mRNA accumulation was abolished by inhibition of phospholipase C (PLC). Taken together, these data indicate that flow increases CD ET-1 production and this is dependent on extracellular and intracellular Ca(2+), PKC, and PLC. These studies suggest a novel pathway for coupling alterations in extracellular fluid volume to CD ET-1 production and ultimately control of CD Na(+) reabsorption.     

Trends in sheltering and welfare at the Hawaiian Humane Society, Oahu, Hawaii

One of the major goals of an animal welfare organization is to reduce the number of homeless, nonhuman animals in a community. In Hawaii, the Hawaiian Humane Society has provided numerous animal welfare services to work toward this goal, such as offering sterilizations and microchipping at reduced rates and facilitating animal adoptions and education. In addition, the Leash Law and the Cat Identification Program have increased animal welfare through increasing the responsibilities of companion animal caregivers (owners). The goal of this research was to assess if temporal changes in animal sheltering have occurred in Hawaii. The study assessed this by analyzing historical data on dogs (Canis familiaris) and cats (Felis catus) admitted, returned to owner, sterilized, euthanized, and adopted from the Humane Societies of Oahu, Hawaii, from 1993 to 2008. The study also analyzed dog and cat admittance and Honolulu population growth from 1975 to 2008. Sterilizations and pets returned to owners have increased significantly, whereas admittance and euthanasia rates have decreased significantly. Thus, although these data cannot conclusively state that there are fewer homeless animals in Hawaii, the results provide positive indicators of reducing homeless pets, especially when coupled with an increase in both the human population of Honolulu County and dog ownership.     

Relationship of 2D:4D finger ratio with muscle strength, testosterone, and androgen receptor CAG repeat genotype

This study aimed to examine the relationship between the ratio of the length of the second and fourth digits (2D:4D) and locomotor muscle strength. Furthermore, two putative mechanisms that might explain any relationship of 2D:4D with muscle strength, specifically serum total and free testosterone, and androgen receptor genotype CAG repeat number (AR CAGn) were investigated. Seventy-seven healthy young Caucasian men completed a thorough assessment of isometric and isokinetic knee extensor strength, with unilateral measurements averaged across both legs and repeated on two occasions. The lengths of the second and fourth fingers of each hand were measured to calculate 2D:4D ratio. Serum total testosterone (TT) and serum hormone binding globulin (SHBG) were measured by ELISA and used to calculate free testosterone (FT). AR CAGn was determined by PCR and microchip electrophoresis. There was no association between mean, left or right hand 2D:4D and isometric or isokinetic knee extensor strength (all, R < 0.12, P > 0.32). TT and FT were unrelated to mean, left or right hand 2D:4D ratio (all, R < 0.12, P > 0.34). Finally AR CAGn was not associated with mean, right or left hand 2D:4D ratio (all, R < 0.20, P > 0.10). This study found no evidence of 2D:4D being related to locomotor muscle strength, TT, FT, or AR CAGn. The reported association of 2D:4D with sports performance does not seem to be explained by an influence on locomotor muscle strength, and could be due to an effect on motor or cognitive skills.     

Were arachnids the first to use combinatorial peptide libraries?

Spiders, scorpions, and cone snails are remarkable for the extent and diversity of gene-encoded peptide neurotoxins that are expressed in their venom glands. These toxins are produced in the form of structurally constrained combinatorial peptide libraries in which there is hypermutation of essentially all residues in the mature-toxin sequence with the exception of a handful of strictly conserved cysteines that direct the three-dimensional fold of the toxin. This gene-based combinatorial peptide library strategy appears to have been first implemented by arachnids almost 400 million years ago, long before cone snails evolved a similar mechanism for generating peptide diversity.     

Sediment inputs from retrogressive thaw slumps drive algal biomass accumulation but not decomposition in Arctic streams,NWT

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