Macrophages hold vital roles in immune defense, wound healing, and tissue homeostasis, and have the exquisite ability to sense and respond to dynamically changing cues in their microenvironment. Much of our understanding of their behavior has been derived from studies performed using in vitro culture systems, in which the cell environment can be precisely controlled. Recent advances in miniaturized culture platforms also offer the ability to recapitulate some features of the in vivo environment and analyze cellular responses at the single-cell level.
View Article and Find Full Text PDFAnimals can mitigate human threats, but how do they do this, and how fast can they adapt? Hunting sperm whales was a major nineteenth century industry. Analysis of data from digitized logbooks of American whalers in the North Pacific found that the rate at which whalers succeeded in harpooning ('striking') sighted whales fell by about 58% over the first few years of exploitation in a region. This decline cannot be explained by the earliest whalers being more competent, as their strike rates outside the North Pacific, where whaling had a longer history, were not elevated.
View Article and Find Full Text PDFMacrophages are versatile cells of the innate immune system that can adopt a variety of functional phenotypes depending on signals in their environment. In previous work, we found that culture of macrophages on fibrin, the provisional extracellular matrix protein, inhibits their inflammatory activation when compared to cells cultured on polystyrene surfaces. Here, we sought to investigate the role of matrix stiffness in the regulation of macrophage activity by manipulating the mechanical properties of fibrin.
View Article and Find Full Text PDFMechanical cues including stretch, compression, and shear stress play a critical role in regulating the behavior of many cell types, particularly those that experience substantial mechanical stress within tissues. Devices that impart mechanical stimulation to cells in vitro have been instrumental in helping to develop a better understanding of how cells respond to mechanical forces. However, these devices often have constraints, such as cost and limited functional capabilities, that restrict their use in research or educational environments.
View Article and Find Full Text PDFMacrophages are versatile and plastic effector cells of the immune system, and contribute to diverse immune functions including pathogen or apoptotic cell removal, inflammatory activation and resolution, and tissue healing. Macrophages function as signaling regulators and amplifiers, and influencing their activity is a powerful approach for controlling inflammation or inducing a wound-healing response in regenerative medicine. This review discusses biomaterials-based approaches for altering macrophage activity, approaches for targeting drugs to macrophages, and approaches for delivering macrophages themselves as a therapeutic intervention.
View Article and Find Full Text PDFWe introduce a new method to geometrically reconstruct eye volume and placement in small-bodied primates based on the three-dimensional contour of the intraorbital surface. We validate it using seven species of living primates, with dry skulls and wet dissections, and test its application on seven species of Paleogene fossils of interest. The method performs well even when the orbit is damaged and incomplete, lacking the postorbital bar and represented only by the orbital floor.
View Article and Find Full Text PDFUnlabelled: Fibrin is a major component of the provisional extracellular matrix formed during tissue repair following injury, and enables cell infiltration and anchoring at the wound site. Macrophages are dynamic regulators of this process, advancing and resolving inflammation in response to cues in their microenvironment. Although much is known about how soluble factors such as cytokines and chemokines regulate macrophage polarization, less is understood about how insoluble and adhesive cues, specifically the blood coagulation matrix fibrin, influence macrophage behavior.
View Article and Find Full Text PDFIntegr Biol (Camb)
September 2016
Macrophages are versatile cells of the immune system that play an important role in both advancing and resolving inflammation. Macrophage activation has been described as a continuum, and different stimuli lead to M1, M2, or mixed phenotypes. In addition, macrophages expressing markers associated with both M1 and M2 function are observed in vivo.
View Article and Find Full Text PDFSecreted proteins play a major role in orchestrating the response of cell populations. However, a quantitative understanding of the dynamic changes in protein secretion in response to microenvironmental cues at the single cell level remains elusive. Measurements taken using traditional molecular techniques typically require bulk cultures, and therefore cannot capture the diversity within cell populations.
View Article and Find Full Text PDFMacrophages adopt a variety of phenotypes that are a reflection of the many functions they perform as part of the immune system. In particular, metabolism is a phenotypic trait that differs between classically activated, proinflammatory macrophages, and alternatively activated, prohealing macrophages. Inflammatory macrophages have a metabolism based on glycolysis while alternatively activated macrophages generally rely on oxidative phosphorylation to generate chemical energy.
View Article and Find Full Text PDFThe North Atlantic right whale (NARW) (Eubalaena glacialis) is one of the world's most threatened whales. It came close to extinction after nearly a millennium of exploitation and currently persists as a population of only approximately 500 individuals. Setting appropriate conservation targets for this species requires an understanding of its historical population size, as a baseline for measuring levels of depletion and progress toward recovery.
View Article and Find Full Text PDFThe Reproducibility Project: Cancer Biology seeks to address growing concerns about reproducibility in scientific research by conducting replicating selected results from a number of high-profile papers in the field of cancer biology. The papers, which were published between 2010 and 2012 were selected on the basis of citations and Altimetric scores (Errington et al., 2014).
View Article and Find Full Text PDFRight whales (Eubalaena spp.) were the focus of worldwide whaling activities from the 16th to the 20th century. During the first part of the 19th century, the southern right whale (E.
View Article and Find Full Text PDFAmerican whalemen sailed out of ports on the east coast of the United States and in California from the 18(th) to early 20(th) centuries, searching for whales throughout the world's oceans. From an initial focus on sperm whales (Physeter macrocephalus) and right whales (Eubalaena spp.), the array of targeted whales expanded to include bowhead whales (Balaena mysticetus), humpback whales (Megaptera novaeangliae), and gray whales (Eschrichtius robustus).
View Article and Find Full Text PDFThe conformational preferences of ethanolamine and its hydrochloride in solution were estimated by comparing experimental NMR vicinal proton-proton coupling constants to semiemprical coupling constants for each staggered rotamer, derived by the Haasnoot-Altona method. Strong gauche preferences are observed for both ethanolamine and its hydrochloride over a wide range of solvent polarities. Concentration was not observed to significantly affect the position of the conformer equilibria.
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