Overweight and Obese Pet Owners: Respondent and Pet Characteristics in the Rural Midwestern United States

The obesity epidemic has impacted both people and pets in the rural Midwestern United States (MWUS). Tailoring health advice to the socio-demographic characteristics and dietary patterns of owners and their pets can help promote adherence to health behavior changes for owners and foster health improvements for both owners and pets. The authors completed this cross-sectional study in the rural MWUS with the objective of describing health-related characteristics of non-over-weight/obese versus overweight/obese [NOO vs. OO] cat and dog owners and their pets. The primary aim was to detect differences that could inform health recommendations. For both cat and dog owners, dietary and lifestyle profiles differed between those who were non-overweight/obese and those who were overweight/obese. NOO dog owners trended toward fewer health problems, took fewer medications (p < 0.02), took more supplements (p < 0.03), and ate less fast food (p < 0.03) and more fish (p < 0.001) than OO owners. Dogs owned by NOO owners had more owner-initiated activity (M ± SD: 44.6 ± 63.0 vs. 27.2 ± 26.4 min/d) and were on more supplements (p < 0.003). NOO cat owners were younger (p < 0.03), had fewer health problems (p < 0.04), took fewer medications (p < 0.04), engaged in more exercise (p < 0.02), and ate less fast food (p < 0.03) than OO cat owners. The only significant difference between cats of NOO vs. OO owners was their predominant gender: 57% vs. 74% female (p < 0.01). These findings have implications for marketing, education, and health care for both owners and pets. Further investigation of the relationship between pet ownership and health is warranted.     

Photosynthetic Energy Conversion Efficiency: Setting a Baseline for Gauging Future Improvements in Important Food and Biofuel Crops

The conversion efficiency (ε_c) of absorbed radiation into biomass (MJ of dry matter per MJ of absorbed photosynthetically active radiation) is a component of yield potential that has been estimated at less than half the theoretical maximum. Various strategies have been proposed to improve ε_c, but a statistical analysis to establish baseline ε_c levels across different crop functional types is lacking. Data from 164 published ε_c studies conducted in relatively unstressed growth conditions were used to determine the means, greatest contributors to variation, and genetic trends in ε_c across important food and biofuel crop species. ε_c was greatest in biofuel crops (0.049–0.066), followed by C₄ food crops (0.046–0.049), C₃ nonlegumes (0.036–0.041), and finally C₃ legumes (0.028–0.035). Despite confining our analysis to relatively unstressed growth conditions, total incident solar radiation and average growing season temperature most often accounted for the largest portion of ε_c variability. Genetic improvements in ε_c, when present, were less than 0.7% per year, revealing the unrealized potential of improving ε_c as a promising contributing strategy to meet projected future agricultural demand.Substantial increases in yield are needed to feed and fuel the world’s growing human population. With an estimated population of nine billion people by the middle of this century (Lutz and Samir, 2010) and rising affluence resulting in greater consumption of grain-fed animal products (Cirera and Masset, 2010), different studies predict that, by midcentury, global crop production will need to increase 60% to 120% over 2005 levels without the expansion of agricultural land area (Tilman et al., 2011; Alexandratos and Bruinsma, 2012).Doubling yields in major food and fuel crops requires considerable effort, especially as yields are beginning to plateau in many major food crops. Yield increases necessary for doubling productivity by midcentury are estimated at 1.16% to 1.31% each year in all cereals (Hall and Richards, 2013), 1.7% per year in wheat (Triticum aestivum; Rosegrant and Agcaoili, 2010), and 2.4% (noncompounding average per year) across all major grain crops (Ray et al., 2013). However, global mean increases from the past 20 to 30 years suggest that yield gains in rice (Oryza sativa) and wheat are approximately 1% (Lopes et al., 2012; Manès et al, 2012; Ray et al., 2013) and declining in some areas of the world (Cassman et al., 2010; Fischer and Edmeades, 2010; Long and Ort, 2010; Ray et al., 2013). Global yearly increases are estimated at 1.3% in soybean (Glycine max) and 1.6% in maize (Zea mays), with similar concerns that yield trends may also be decreasing in some major growing regions (Lobell and Gourdji, 2012; Ray et al., 2013).Efforts to increase yields in the next few decades must also account for environmental and sustainability goals (Sayer et al., 2013) as well as heightened environmental stresses predicted to occur due to climate change, which are already responsible for some of the stagnation in yield increases. Anthropogenic sources of greenhouse gases have caused an approximately 1°C increase in land surface temperatures since 1900, and global mean surface temperatures are likely to increase by up to 2.4°C to 4.8°C by the end of the century (IPCC, 2013). Drought is also expected to become more frequent and intense in many regions of the world (Dai, 2011; IPCC, 2013). Of the variability present in major food crop yield gains, 30% can be explained by climate change alone (Lobell and Field, 2007), with drastic decreases in barley (Hordeum vulgare), maize, rice, sorghum (Sorghum bicolor), soybean, and wheat yields as average growing season temperatures surpass the temperature optimum for each crop (Lobell and Gourdji, 2012). Current levels of atmospheric CO₂ concentration [CO₂] are the highest they have been in at least 800,000 years (IPCC, 2013). Elevated [CO₂] increases water use efficiency (Ainsworth and Long, 2005, Bernacchi et al., 2007, Leakey et al., 2009), but probably not to an extent that would mitigate the resulting reductions in yield caused by higher temperature and higher vapor pressure deficit (Ort and Long, 2014). Additionally, any fertilization effects on C₃ yields due to elevated [CO₂] would be at least in part negated by drought and temperature stress, leaving yield increases far from optimal (Long et al., 2006a; Lobell and Gourdji, 2012).     

Physical Activity Differentially Affects the Cecal Microbiota of Ovariectomized Female Rats Selectively Bred for High and Low Aerobic Capacity

The gut microbiota is considered a relevant factor in obesity and associated metabolic diseases, for which postmenopausal women are particularly at risk. Increasing physical activity has been recognized as an efficacious approach to prevent or treat obesity, yet the impact of physical activity on the microbiota remains under-investigated. We examined the impacts of voluntary exercise on host metabolism and gut microbiota in ovariectomized (OVX) high capacity (HCR) and low capacity running (LCR) rats. HCR and LCR rats (age = 27wk) were OVX and fed a high-fat diet (45% kcal fat) ad libitum and housed in cages equipped with (exercise, EX) or without (sedentary, SED) running wheels for 11wk (n = 7-8/group). We hypothesized that increased physical activity would hinder weight gain, increase metabolic health and shift the microbiota of LCR rats, resulting in populations more similar to that of HCR rats. Animals were compared for characteristic metabolic parameters including body composition, lipid profile and energy expenditure; whereas cecal digesta were collected for DNA extraction. 16S rRNA gene-based amplicon Illumina MiSeq sequencing was performed, followed by analysis using QIIME 1.8.0 to assess cecal microbiota. Voluntary exercise decreased body and fat mass, and normalized fasting NEFA concentrations of LCR rats, despite only running one-third the distance of HCR rats. Exercise, however, increased food intake, weight gain and fat mass of HCR rats. Exercise clustered the gut microbial community of LCR rats, which separated them from the other groups. Assessments of specific taxa revealed significant (p<0.05) line by exercise interactions including shifts in the abundances of Firmicutes, Proteobacteria, and Cyanobacteria. Relative abundance of Christensenellaceae family was higher (p = 0.026) in HCR than LCR rats, and positively correlated (p<0.05) with food intake, body weight and running distance. These findings demonstrate that exercise differentially impacts host metabolism and gut microbial communities of female HCR and LCR rats without ovarian function.     

In vivo bipartite interaction between the Hsp40 Sis1 and Hsp70 in Saccharomyces cerevisiae

The essential Hsp40, Sis1, is a J-protein cochaperone for the Ssa class of Hsp70's of Saccharomyces cerevisiae. Sis1 is required for the maintenance of the prion [RNQ(+)], as Sis1 lacking its 55-amino-acid glycine-rich region (G/F) does not maintain [RNQ(+)]. We report that overexpression of Sis1DeltaG/F in an otherwise wild-type strain had a negative effect on both cell growth and [RNQ(+)] maintenance, while overexpression of wild-type Sis1 did not. Overexpression of the related Hsp40 Ydj1 lacking its G/F region did not cause inhibition of growth, indicating that this dominant effect of Sis1DeltaG/F is not a characteristic shared by all Hsp40's. Analysis of small deletions within the SIS1 G/F region indicated that the observed dominant effects were caused by the absence of sequences known to be important for Sis1's unique cellular functions. These inhibitory effects of Sis1DeltaG/F were obviated by alterations in the N-terminal J-domain of Sis1 that affect interaction with Ssa's ATPase domain. In addition, a genetic screen designed to isolate additional mutations that relieved these inhibitory effects identified two residues in Sis1's carboxy-terminal domain. These alterations disrupted the interaction of Sis1 with the 10-kD carboxy-terminal regulatory domain of Ssa1, indicating that Sis1 has a bipartite interaction with Ssa in vivo.     

Low and annually variable migratory connectivity in a long‐distance migrant: Whinchats Saxicola rubetra may show a bet‐hedging strategy

The spatial scale of non‐breeding areas used by long‐distance migrant animals can vary from specific, relatively small non‐breeding areas for each independent breeding population (high connectivity) to a distribution over a large non‐breeding area with mixing of breeding populations (low connectivity). Measuring variation in the degree of connectivity and how it arises is crucial to predict how migratory animals can respond to global habitat and climate change because low connectivity is likely to be an adaptation to environmental uncertainty. Here, we assess whether use of non‐breeding areas in a long‐distance migrant may be stochastic by measuring the degree of connectivity, and whether it is annually variable. Twenty‐nine wintering Whinchats tagged with geolocators over 2 years within 40 km² in central Nigeria were found to be breeding over 2.55 million km² (26% of the land area of Europe), without an asymptote being approached in the relationship between area and sample size. Ranges differed in size between years by 1.51 million km² and only 15% of the total breeding range across both years overlapped (8% overlap between years when only first‐year birds were considered), well above the range size difference and below the proportion of overlap that would be predicted from two equivalent groups breeding at random locations within the observed range. Mean distance between breeding locations (i.e. migratory spread) differed significantly between years (604 ± 18 km in 2013 and 869 ± 33 km in 2014). The results showed very low and variable connectivity that was reasonably robust to the errors and assumptions inherent in the use of geolocators, but with the caveat of having only ranges of 2 years to compare, and the sensitivity of range to the breeding locations of a small number of individuals. However, if representative, the results suggest the scope for between‐year variation (cohort effects) to determine migrant distribution on a large scale. Furthermore, for species with similarly low connectivity, we would predict breeding population trends to reflect average conditions across large non‐breeding areas: thus, as large areas of Africa become subject to habitat loss, migrant populations throughout Europe will decline.     

Caspase-resistant Golgin-160 disrupts apoptosis induced by secretory pathway stress and ligation of death receptors

Golgin-160 is a coiled-coil protein on the cytoplasmic face of the Golgi complex that is cleaved by caspases during apoptosis. We assessed the sensitivity of cell lines stably expressing wild-type or caspase-resistant golgin-160 to several proapoptotic stimuli. Cells expressing a caspase-resistant mutant of golgin-160 were strikingly resistant to apoptosis induced by ligation of death receptors and by drugs that induce endoplasmic reticulum (ER) stress, including brefeldin-A, dithiothreitol, and thapsigargin. However, both cell lines responded similarly to other proapoptotic stimuli, including staurosporine, anisomycin, and etoposide. The caspase-resistant golgin-160 dominantly prevented cleavage of endogenous golgin-160 after ligation of death receptors or induction of ER stress, which could be explained by a failure of initiator caspase activation. The block in apoptosis in cells expressing caspase-resistant golgin-160 could not be bypassed by expression of potential caspase cleavage fragments of golgin-160, or by drug-induced disassembly of the Golgi complex. Our results suggest that some apoptotic signals (including those initiated by death receptors and ER stress) are sensed and integrated at Golgi membranes and that golgin-160 plays an important role in transduction of these signals.     

Taxonomic patterns in the nitrogen assimilation of soil prokaryotes

Nitrogen (N) is frequently a limiting nutrient in soil; its availability can govern ecosystem functions such as primary production and decomposition. Assimilation of N by microorganisms impacts the availability of N in soil. Despite its established ecological significance, the contributions of microbial taxa to N assimilation are unknown. Here we measure N uptake and use by microbial phylotypes and taxonomic groups within a diverse assemblage of soil microbes through quantitative stable isotope probing (qSIP) with ¹⁵N. Following incubation with ¹⁵ , distinct patterns of ¹⁵N assimilation among taxonomic groups were observed. For instance, glucose addition stimulated ¹⁵N assimilation in most members of Actinobacteria and Proteobacteria but generally decreased ¹⁵N use by Firmicutes and Bacteriodetes. While is considered a preferred and universal source of N to prokaryotes, the majority (> 80%) of N assimilation in our soils could be attributed to a handful of active orders. Characterizing N assimilation of taxonomic groups with ¹⁵N qSIP may provide a basis for understanding how microbial community composition influences N availability in the environment.     

Complexities in horseradish peroxidase-catalyzed oxidation of dihydroxyphenoxazine derivatives: appropriate ranges for pH values and hydrogen peroxide concentrations in quantitative analysis

The highly sensitive, convenient fluorescence assay, based on the oxidation of nonfluorescent 10-acetyl-3,7-dihydroxyphenoxazine (Amplex Red) to highly fluorescent resorufin, is becoming increasingly popular for hydrogen peroxide quantitation. Yet, the intricacies of the horseradish peroxidase-catalyzed oxidation of the reductant substrate Amplex Red by hydrogen peroxide and the resulting resorufin could complicate the assay design and data interpretation. In particular, substrate inhibition and enzyme inactivation at higher hydrogen peroxide concentrations were known to affect the enzyme kinetics and end-point fluorescence. In addition, here we report the spontaneous transformation of resorufin to less or nonfluorescent product(s) in the absence of hydrogen peroxide and horseradish peroxidase. This spontaneous decay of resorufin fluorescence is most prominent in the pH range 6.2-7.7, likely due to general base-catalyzed de-N-acetylation and polymerization of resorufin. From a practical point of view, precautions for properly designing assays for hydrogen peroxide or characterizing hydrogen peroxide-generating systems are discussed based on the spontaneous transformation of resorufin to less fluorescent compound(s), substrate inhibition and enzyme inactivation at higher (>100 microM) hydrogen peroxide concentrations, and enzymatic oxidation of resorufin to nonfluorescent resazurin.