Efficacy of ethylene oxide-sterilized waterproof cases for handheld cameras as sterile barriers for intraoperative imaging and recording.

Objective: To evaluate the efficacy of ethylene oxide (EtOH) sterilization of 4 different waterproof camera cases and the ability of those sterilized cases to maintain a sterile barrier for intraoperative camera use.

Sample: 3 action cameras, 1 smartphone, and associated waterproof cases.

Procedures: Cases were inoculated by immersion in medium containing , and and then manually cleaned and subjected to EtOH sterilization.

Biomimetic Model of Contractile Cardiac Tissue with Endothelial Networks Stabilized by Adipose-Derived Stromal/Stem Cells.

Cardiac tissue engineering strategies have the potential to regenerate functional myocardium following myocardial infarction. In this study, we utilized novel electrospun fibrin microfiber sheets of different stiffnesses (50.0 ± 11.

Regenerative and durable small-diameter graft as an arterial conduit.

Despite significant research efforts, clinical practice for arterial bypass surgery has been stagnant, and engineered grafts continue to face postimplantation challenges. Here, we describe the development and application of a durable small-diameter vascular graft with tailored regenerative capacity. We fabricated small-diameter vascular grafts by electrospinning fibrin tubes and poly(ε-caprolactone) fibrous sheaths, which improved suture retention strength and enabled long-term survival.

Adipose-derived Stem/Stromal Cells on Electrospun Fibrin Microfiber Bundles Enable Moderate Muscle Reconstruction in a Volumetric Muscle Loss Model.

Current treatment options for volumetric muscle loss (VML) are limited due to donor site morbidity, lack of donor tissue, and insufficient functional recovery. Tissue-engineered skeletal muscle grafts offer the potential to significantly improve functional outcomes. In this study, we assessed the potential pro-myogenic effects of human adipose-derived stem cells (ASCs) seeded onto electrospun uniaxially aligned fibrin hydrogel microfiber bundles.

Synthetic Nanofiber-Reinforced Amniotic Membrane via Interfacial Bonding.

Severe damage to the ocular surface can result in limbal stem cell (LSC) deficiency, which contributes to loss of corneal clarity, potential vision loss, chronic pain, photophobia, and keratoplasty failure. Human amniotic membrane (AM) is the most effective substrate for LSC transplantation to treat patients with LSC deficiency. However, the widespread use of the AM in the clinic remains a challenge because of the high cost for preserving freshly prepared AM and the weak mechanical strength of lyophilized AM.

Rapid Iron Reduction Rates Are Stimulated by High-Amplitude Redox Fluctuations in a Tropical Forest Soil.

Iron oxides are important structural and biogeochemical components of soils that can be strongly altered by redox-driven processes. This study examined the influence of temporal oxygen variations on Fe speciation in soils from the Luquillo Critical Zone Observatory (Puerto Rico). We incubated soils under cycles of oxic-anoxic conditions (τ:τ = 1:6) at three frequencies with and without phosphate addition.

The thermodynamics of protein aggregation reactions may underpin the enhanced metabolic efficiency associated with heterosis, some balancing selection, and the evolution of ploidy levels.

Identifying the physical basis of heterosis (or "hybrid vigor") has remained elusive despite over a hundred years of research on the subject. The three main theories of heterosis are dominance theory, overdominance theory, and epistasis theory. Kacser and Burns (1981) identified the molecular basis of dominance, which has greatly enhanced our understanding of its importance to heterosis.

Characterization of a novel bioreactor system for 3D cellular mechanobiology studies.

In vitro engineering systems can be powerful tools for studying tissue development in response to biophysical stimuli as well as for evaluating the functionality of engineered tissue grafts. It has been challenging, however, to develop systems that adequately integrate the application of biomimetic mechanical strain to engineered tissue with the ability to assess functional outcomes in real time. The aim of this study was to design a bioreactor system capable of real-time conditioning (dynamic, uniaxial strain, and electrical stimulation) of centimeter-long 3D tissue engineered constructs simultaneously with the capacity to monitor local strains.

Fabrication of 3-dimensional multicellular microvascular structures.

Despite current advances in engineering blood vessels over 1 mm in diameter and the existing wealth of knowledge regarding capillary bed formation, studies for the development of microvasculature, the connecting bridge between them, have been extremely limited so far. Here, we evaluate the use of 3-dimensional (3D) microfibers fabricated by hydrogel electrospinning as templates for microvascular structure formation. We hypothesize that 3D microfibers improve extracellular matrix (ECM) deposition from vascular cells, enabling the formation of freestanding luminal multicellular microvasculature.

Establishing ecological reference conditions and tracking post-application effectiveness of lanthanum-saturated bentonite clay (Phoslock®) for reducing phosphorus in aquatic systems: an applied paleolimnological approach.

Innovative management strategies for nutrient enrichment of freshwater are important in the face of this increasing global problem, however many strategies are not assessed over long enough time periods to establish effectiveness. Paleolimnological techniques using diatoms as biological indicators were utilized to establish ecological reference conditions, environmental variation, and the effectiveness of lanthanum-saturated bentonite clay (brand name: Phoslock(®)) applied to reduce water column phosphorus (P) concentrations in four waterbodies in Ontario, Canada, and eastern Australia. In sediment cores from the two Canadian sites, there were short-lived changes to diatom assemblages, relative to inferred background conditions, and a temporary reduction in both measured and diatom-inferred total phosphorus (TP) before returning to pre-application conditions (particularly in the urban stormwater management pond which has a high flushing rate and responds rapidly to precipitation and surface run-off).

Creating polymer hydrogel microfibres with internal alignment via electrical and mechanical stretching.

Hydrogels have been widely used for 3-dimensional (3D) cell culture and tissue regeneration due to their tunable biochemical and physicochemical properties as well as their high water content, which resembles the aqueous microenvironment of the natural extracellular matrix. While many properties of natural hydrogel matrices are modifiable, their intrinsic isotropic structure limits the control over cellular organization, which is critical to restore tissue function. Here we report a generic approach to incorporate alignment topography inside the hydrogel matrix using a combination of electrical and mechanical stretching.

A novel in vitro model for microvasculature reveals regulation of circumferential ECM organization by curvature.

In microvascular vessels, endothelial cells are aligned longitudinally whereas several components of the extracellular matrix (ECM) are organized circumferentially. While current three-dimensional (3D) in vitro models for microvasculature have allowed the study of ECM-regulated tubulogenesis, they have limited control over topographical cues presented by the ECM and impart a barrier for the high-resolution and dynamic study of multicellular and extracellular organization. Here we exploit a 3D fibrin microfiber scaffold to develop a novel in vitro model of the microvasculature that recapitulates endothelial alignment and ECM deposition in a setting that also allows the sequential co-culture of mural cells.

The implications of gene heterozygosity for protein folding and protein turnover.

The offspring of closely related parents often suffer from inbreeding depression, sometimes resulting in a slower growth rate for inbred offspring relative to non-inbred offspring. Previous research has shown that some of the slower growth rate of inbred organisms can be attributed to the inbred organisms' increased levels of protein turnover. This paper attempts to show that the higher levels of protein turnover among inbred organisms can be attributed to accumulations of misfolded and aggregated proteins that require degradation by the inbred organisms' protein quality control systems.

Adhesion of Shewanella oneidensis MR-1 to iron (Oxy)(Hydr)oxides: microcolony formation and isotherm.

The adhesion of dissimilatory metal reducing bacteria (DMRB) to iron (oxy)(hydr)oxides may play an important role in their respiration on ferric iron-containing minerals, but few quantitative surface cell density measurements have been made thus far. We used confocal microscopy to examine the adhesion of a common DMRB species, Shewanella oneidensis MR-1, onto iron (oxy)(hydr)oxide particulate-coated glass slides across a broad range of bulk (i.e.

Outer membrane-associated serine protease involved in adhesion of Shewanella oneidensis to Fe(III) oxides.

The facultative anaerobe Shewanella oneidensis MR-1 respires a variety of anaerobic electron acceptors, including insoluble Fe(III) oxides. S. oneidensis employs a number of novel strategies for respiration of insoluble Fe(III) oxides, including localization of respiratory proteins to the cell outer membrane (OM).

The widespread threat of calcium decline in fresh waters.

Calcium concentrations are now commonly declining in softwater boreal lakes. Although the mechanisms leading to these declines are generally well known, the consequences for the aquatic biota have not yet been reported. By examining crustacean zooplankton remains preserved in lake sediment cores, we document near extirpations of calcium-rich Daphnia species, which are keystone herbivores in pelagic food webs, concurrent with declining lake-water calcium.

Propagation failure dynamics of wave trains in excitable systems.

We report experimental and numerical results on temporal patterns of propagation failures in reaction-diffusion systems. Experiments employ the 1,4-cyclohexanedione Belousov-Zhabotinsky reaction. The propagation failures occur in the frontier region of the wave train and can profoundly affect its expansion speed.

Front aggregation in multiarmed excitation vortices.

Using the Belousov-Zhabotinsky reaction, we study the pinning of multiarmed spiral waves to nonexcitable obstacles. With increasing obstacle size, the individual arms switch from a repulsive to an attractive state. This transition yields densely aggregated spiral arms and is caused by anomalous dispersion.

Quantized spiral tip motion in excitable systems with periodic heterogeneities.

Meandering spiral tips in homogeneous reaction-diffusion systems are characterized by two generically incommensurate radii and frequencies. Here, we create periodic perturbations in space to induce a transition to commensurate radii and frequencies that exhibit a devil's staircase. The plateaus of the staircase correspond to pinned or complex periodic orbits of the spiral tip.

Conduit properties and karstification in the unconfined Floridan aquifer.

Exchange of water between conduits and matrix is an important control on regional chemical compositions, karstification, and quality of ground water resources in karst aquifers. A sinking stream (Santa Fe River Sink) and its resurgence (River Rise) in the unconfined portion of the Floridan Aquifer provide the opportunity to monitor conduit inflow and outflow. The use of temperature as a tracer allows determination of residence times and velocities through the conduit system.