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Bats provide numerous ecosystem services as they pollinate, disperse seeds, and reduce insect populations. It is thus vital to monitor and understand their foraging habits. We analyzed sterols and stanols in a rare discovery of a ∼4,300‐year‐old bat guano deposit from a Jamaican cave to infer relative changes in bat feeding guilds over four millennia. In this deposit, zoosterols and phytosterols, in conjunction with δ13C and C/N data, revealed two periods of increased frugivory relative to insectivory from ca. 1000‐500 BCE and ca. 700–1900 CE. We propose two possible explanations for these intervals of increased frugivory relative to insectivory. (1) Previous paleoclimate data suggested these intervals were warmer and drier in the region, which we hypothesize resulted in reduced insect availability. We supported these inferences by comparing the same analytes in fresh guano from frugivorous, insectivorous, and sanguinivorous (blood‐drinking) bats, which showed that bats with animal‐based diets produced guano with lower C/N ratios and higher cholesterol/(cholesterol + sitosterol) ratios than those with fruit‐based diets. (2) The change in the chemical composition of the bat guano during these two periods may also be the result of a shift in the relative species composition of the bat roost that is a greater proportion of frugivorous relative to insectivorous bats during these two periods. This novel, non‐invasive method, based on the chemical composition of bat guano, tracked changes in tropical bat foraging habits extending back in time over four millennia. Plain Language Summary: Bats play important roles in pollinating flowers, dispersing seeds, and controlling insect populations. It is therefore important that we understand how human activities and natural events alter bat feeding habits, which can affect their ability to perform these important functions. Our study consisted of two parts. First, we showed how the chemical composition of fresh bat guano revealed whether bats ate plants, insects, or blood. We then used this information to study a ∼4,300‐year‐old bat guano core collected from a cave in Jamaica to determine if we could observe long‐term dietary changes in the bat roost. Our study revealed alternating periods of increased fruit relative to insect consumption. We suggest that (1) the bat roost generally favoured a fruit‐based diet during warmer and drier periods, suggesting that climate affected feeding habits; and/or (2) the roost was composed of more frugivorous relative to insectivorous bats during those two periods. This relatively non‐invasive method offers a new way to study how bat feeding guilds are affected by different environmental conditions and will be useful to monitor and protect bat populations in the future. Key Points: Bat foraging habits can be studied by analyzing their guano for sterols, stanols, and stable isotopes of carbon and nitrogenThe diets of frugivorous, nectarivorous, and sanguinivorous bats were well‐characterized by the sterol and stanol ratios in their guanoWe examined the composition of a 4,300‐year‐old bat guano deposit and identified two periods of increased fruit‐based foraging [ABSTRACT FROM AUTHOR]

The article discusses the implementation of positive blood donation experience to improve the conditioning and perceptions of the donors, partners and employees. The blood donor clinics organizers especially the business sector or in shopping centers are sensitive especially when it comes to the blood donation experience. In evaluating the adopted method it includes visitation of the blood donor clinics and interviews with the employees and the blood donor clinics as well as the administrator of the shopping center.

A letter to the editor in response to article “Vasopressin Antagonists for Patients With Acute Heart Failure: Interpreting New Clinical and Translational Data" by Feldman, A.M in the previous issue is presented.

Zebra mussels (Dreissena polymorpha) are freshwater mollusks that have recently infested the Great Lakes ecosystem. Possessing a large capacity for filtration, these mussel populations act as bioconcentrators for contaminants, such as heavy metals, found in the Great Lakes ecosystem. Metallothionein is a low-molecular-weight, heavy metal-binding protein found in most living organisms. Characterization and partial purification of metallothionein-like Cd-binding proteins from zebra mussels we re performed. Zebra mussels were exposed to 500 mu g/L Cd for 14 d. During the exposure period, two mussels were removed on alternate days for analysis of Cd-binding proteins. Gel-filtration high-performance liquid chromatography-microatomization-atomic absorption spectrophotometry results showed a single Cd-binding molecular weight protein fraction after 2 d of Cd exposure. After 10 d of Cd exposure, however, mussels exhibited an additional, higher molecular weight, Cd-binding protein fraction. The lower molecular weight metallothionein-like Cd-binding protein was further isolated and purified by acetone fractionation, Sephadex G75, and diethylaminoethyl anion-exchange chromatography. The quantities of Zn, Cu, and Cd in the anion-exchange metallothionein-like protein isoforms were determined by inductively coupled plasma-mass spectrometry. The ability to bioconcentrate heavy metals in a metallothionein-like form coupled with their large population in the Great Lakes make zebra mussels suitable for use in a freshwater biomonitoring program for aquatic metal contamination. [ABSTRACT FROM AUTHOR]

Cardiac troponin is extensively used as a biomarker in modern medicine due to its diagnostic capability for myocardial injury, as well as its predictive and prognostic value for cardiac diseases. However, heterophile antibodies, antitroponin antibodies, and macrotroponin complexes can be observed both in seemingly healthy individuals and patients with cardiac diseases, potentially leading to false positive or disproportionate elevation of cTn (cardiac troponin) assay results and introducing discrepancies in clinical interpretations with impact on medical management. In this review article, we describe the possible mechanisms of cTn release and the sources of variations in the assessment of circulating cTn levels. We also explore the pathophysiological mechanisms underlying antitroponin antibody development and discuss the influence exerted by macrotroponin complexes on the results of immunoassays. Additionally, we explore approaches to detect these complexes by presenting various clinical scenarios encountered in routine clinical practice. Finally, unsolved questions about the development, prevalence, and clinical significance of cardiac autoantibodies are discussed.

The unfolded protein response (UPR) is a coordinated program that promotes cell survival under conditions of endoplasmic reticulum stress and is required in tumor progression as well. To date, no specific small molecule inhibitor targeting this pathway has been identified. Pancreatic endoplasmic reticulum kinase (PERK), one of the UPR transducers, is an eIF2α kinase. Compromising PERK function inhibits tumor growth in mice, suggesting that PERK may be a cancer drug target, but identifying a specific inhibitor of any kinase is challenging. The goal of this study was to identify some pair-wise receptor-ligand atomic contacts that confer selective PERK inhibition. Compounds selectively inhibiting PERK-mediated phosphorylation in vitro were identified using an initial virtual library screen, followed by structure-activity hypothesis testing. The most potent PERK selective inhibitors utilize three specific kinase active site contacts that, when absent from chemically similar compounds, abrogates the inhibition: (i) a strong van der Waals contact with PERK residue Met7, (ii) interactions with the N-terminal portion of the activation loop, and (iii) groups providing electrostatic complementarity to Asp144. Interestingly, the activation loop contact is required for PERK selectivity to emerge. Understanding these structure-activity relationships may accelerate rational PERK inhibitor design., (© 2010 John Wiley & Sons A/S.)