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Mechanical loading bioreactors capable of applying uniaxial tensile strains are emerging to be a valuable tool to investigate physiologically relevant cellular signaling pathways and biochemical expression. In this study, we have introduced a simple and cost-effective uniaxial tensile strain bioreactor for the application of precise and homogenous uniaxial strains to 3D cell-encapsulated collagen constructs at physiological loading strains (0-12%) and frequencies (0.01-1 Hz). The bioreactor employs silicone-based loading chambers specifically designed to stretch constructs without direct gripping to minimize stress concentration at the ends of the construct and preserve its integrity. The loading chambers are driven by a versatile stepper motor ball-screw actuation system to produce stretching of the constructs. Mechanical characterization of the bioreactor performed through Finite Element Analysis demonstrated that the constructs experienced predominantly uniaxial tensile strain in the longitudinal direction. The strains produced were found to be homogenous over a 15 × 4 × 2 mm region of the construct equivalent to around 60% of the effective region of characterization. The strain values were also shown to be consistent and reproducible during cyclic loading regimes. Biological characterization confirmed the ability of the bioreactor to promote cell viability, proliferation, and matrix organization of cell-encapsulated collagen constructs. This easy-to-use uniaxial tensile strain bioreactor can be employed for studying morphological, structural, and functional responses of cell-embedded matrix systems in response to physiological loading of musculoskeletal tissues. It also holds promise for tissue-engineered strategies that involve delivery of mechanically stimulated cells at the site of injury through a biological carrier to develop a clinically useful therapy for tissue healing. Biotechnol. Bioeng. 2017;114: 1878-1887. © 2017 Wiley Periodicals, Inc.

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The thoracic surgery patient population and surgical techniques introduce unique physiologic considerations when devising an anesthetic plan. Premedication prior to induction of anesthesia can be utilized to mitigate the risk of perioperative bronchospasm. Induction agents should be chosen on a case-by-case basis, with considerations given to propensity for reactive airway complications and concomitant cardiopulmonary disease. Thoracic surgery often utilizes one-lung ventilation techniques, which can be accomplished with a double-lumen endotracheal tube or an endobronchial blocker. One-lung ventilation, hypoxic pulmonary vasoconstriction, avoidance of acute lung injury, and postoperative pain control all complicate devising an anesthetic plan for thoracic surgical patients and can be addressed in several ways.