Skin and hair on-a-chip: in vitro skin models versus ex vivo tissue maintenance with dynamic perfusion.

Substantial progress has been achieved over the last few decades in the development of skin equivalents to model the skin as an organ. However, their static culture still limits the emulation of essential physiological properties crucial for toxicity testing and compound screening. Here, we describe a dynamically perfused chip-based bioreactor platform capable of applying variable mechanical shear stress and extending culture periods.

A dynamic multi-organ-chip for long-term cultivation and substance testing proven by 3D human liver and skin tissue co-culture.

Current in vitro and animal tests for drug development are failing to emulate the systemic organ complexity of the human body and, therefore, to accurately predict drug toxicity. In this study, we present a multi-organ-chip capable of maintaining 3D tissues derived from cell lines, primary cells and biopsies of various human organs. We designed a multi-organ-chip with co-cultures of human artificial liver microtissues and skin biopsies, each a (1)/100,000 of the biomass of their original human organ counterparts, and have successfully proven its long-term performance.

De novo formation and ultra-structural characterization of a fiber-producing human hair follicle equivalent in vitro.

Across many tissues and organs, the ability to create an organoid, the smallest functional unit of an organ, in vitro is the key both to tissue engineering and preclinical testing regimes. The hair follicle is an organoid that has been much studied based on its ability to grow quickly and to regenerate after trauma. But hair follicle formation in vitro has been elusive.

Design and prototyping of a chip-based multi-micro-organoid culture system for substance testing, predictive to human (substance) exposure.

Dynamic miniaturized human multi-micro-organ bioreactor systems are envisaged as a possible solution for the embarrassing gap of predictive substance testing prior to human exposure. A rational approach was applied to simulate and design dynamic long-term cultures of the smallest possible functional human organ units, human "micro-organoids", on a chip the shape of a microscope slide. Each chip contains six identical dynamic micro-bioreactors with three different micro-organoid culture segments each, a feed supply and waste reservoirs.

Submural histopathologic changes attributable to peracute laminitis in horses.

Objective: To describe submural histopathologic changes attributable to peracute laminitis in horses.

Animals: 20 adult horses.

Procedure: A concurrent-control design was used to compare laminar lesions in 10 horses subjected to carbohydrate-induced laminitis with laminar characteristics of 10 sex- and aged-matched control horses with normal feet.

Evaluation of systemic immunologic hyperreactivity after intradermal testing in horses with chronic laminitis.

Objective: To determine whether systemic immunologic hyperreactivity exists in horses with chronic laminitis, compared with responses for nonlaminitic horses.

Animals: 7 nonlaminitic horses and 7 CL horses.

Procedure: In experiment 1, intradermal testing (IDT) was performed on 7 nonlaminitic and 7 CL horses to evaluate the response to a combination of 70 allergens at 15 and 30 minutes and 4 and 24 hours after injection.

Short-term effect of therapeutic shoeing on severity of lameness in horses with chronic laminitis.

Objective: To evaluate the short-term effects of 4 therapeutic shoeing systems on lameness and voluntary limb-load distribution in horses with chronic laminitis.

Animals: 10 horses with chronic laminitis.

Procedures: A clinical trial was conducted that used a concurrent control, crossover design to evaluate the relative effectiveness of a standard flat shoe, fullered egg-bar shoe, heart-bar shoe, and modified equine digital support system to alleviate chronic lameness in horses.

Effect of prolonged water immersion on equine hoof epidermis in vitro.

Objective: To evaluate the effect of prolonged water exposure on tissue mass and solutes of outer and inner layers of the stratum medium, sole, frog, and the stratum medium (SMZA) zona alba layer of horses' hooves. SPECIMEN POPULATION: 10 hooves from 10 horses without foot abnormalities.

Procedures: Hoof wall tissue specimens were obtained and immersed for 10 days in distilled deionized water.

Effectiveness of glyceryl trinitrate for enhancing digital submural perfusion in horses.

Objective: To evaluate the clinical efficacy of topically administered glyceryl trinitrate (GTN) for inducing digital submural vasodilation in clinically normal horses.

Animals: 7 adult horses without foot abnormalities.

Procedures: A concurrent-control crossover design was used to determine whether topical application of GTN ointment for prevention or treatment of laminitis would result in a detectable increase in digital perfusion.

Effectiveness of a unique dihydropyridine (BAYTG 1000) for prevention of laminitis in horses.

Objective: To determine whether a unique dihydropyridine (BAYTG 1000) would be beneficial in preventing laminitis in horses.

Animals: 16 clinically normal adult horses.

Procedure: 8 pairs of horses were used in a controlled double-blind study, using sex- and age-matched horses randomly assigned to treatment or control groups.