In vivo tissue engineering of a trilayered leaflet-shaped tissue construct

Aim: We aimed to develop a leaflet-shaped trilayered tissue construct mimicking the morphology of native heart valve leaflets. Materials & methods: Electrospinning and in vivo tissue engineering methods were employed. Results: We developed leaflet-shaped microfibrous scaffolds, each with circumferentially, randomly and radially oriented three layers mimicking the trilayered, oriented structure of native leaflets. After 3 months in vivo tissue engineering with the scaffolds, the generated leaflet-shaped tissue constructs had a trilayered structure mimicking the orientations of native heart valve leaflets. Presence of collagen, glycosaminoglycans and elastin seen in native leaflets was observed in the engineered tissue constructs. Conclusion: Trilayered, oriented fibrous scaffolds brought the orientations of the infiltrated cells and their produced extracellular matrix proteins into the constructs.

Targeting gap junctional intercellular communication by hepatocarcinogenic compounds

Gap junctions in liver, as in other organs, play a critical role in tissue homeostasis. Inherently, these cellular constituents are major targets for systemic toxicity and diseases, including cancer. This review provides an overview of chemicals that compromise liver gap junctions, in particular biological toxins, organic solvents, pesticides, pharmaceuticals, peroxides, metals and phthalates. The focus in this review is placed upon the mechanistic scenarios that underlie these adverse effects. Further, the potential use of gap junctional activity as an in vitro biomarker to identify non-genotoxic hepatocarcinogenic chemicals is discussed.

[In vitro and in vivo intestinal absorption of Huanglian decoction in multi-component environment]

The effect of drugs in the body is always inseparable with the dynamic processes of absorption, distribution, metabolism and excretion. For oral drug, absorption, as the first link to enter the body, is particularly valued. Traditional Chinese medicine has multiple components and multiple targets, and the nature of its single composition is different from that in the multicomponent environment. Alkaloids in Huanglian extract was used as the main object in this study to establish an analytical method for determining the content of alkaloids in Huanglian. In addition, the compositions of the Huanglian aqueous extract solution which can be absorbed through intestinal wall into blood, were initially determined by the means of everted gut sac and in intestinal perfusion with venous sampling experiment. This paper can provide data reference and support for the further study on the absorption and metabolism of Huanglian.

Surgical Procedures Required for Measurement Reduce Nerve Conduction Velocity: An In Vivo and In Vitro Comparative Study

Background: Although in vitro methods have disadvantages, they are still commonly used to measure nerve conduction velocity (NCV) in experimental studies. Therefore, this study was designed to demonstrate the effect of the surgical procedures required for in vitro methods on nerve fibers and the effect of in vivo and in vitro methods on the results of electrophysiological measurements.Methods: Rats were assigned to the in vivo (control-1, injury-1, and diabetic-1) and in vitro (control-2, injury-2, and diabetic-2) groups. The NCV and compound action potential amplitudes were measured, and the nerve fibers were histologically examined.Results: Damaged axons and myelin sheaths were observed in the control-2 group. The electrophysiological values of the in vitro groups were lower than those of the in vivo groups. Furthermore, these values were lower for the diabetic and injury groups than for the control groups.Conclusions: This study showed that the surgical procedures required for the in vitro method reduced the measured values. Owing to the previous and current disadvantages of the in vitro method, the in vivo method was more sensitive for the NCV measurement. Moreover, measurements can be performed using the current in vivo method for small nerve fibers.