In functional tissue engineering, the application of dynamic loading has been shown to improve the mechanical properties of chondrocyte-seeded agarose hydrogels relative to unloaded free swelling controls. The goal of this study is to determine the effect of dynamic loading on the transport of nutrients in tissue-engineered constructs. To eliminate confounding effects, such as nutrient consumption in cell-laden disks, this study examines the response of solute transport due to loading using a model system of acellular agarose disks and dextran in phosphate-buffered saline (3 and 70 kDa). An examination of the passive diffusion response of dextran in agarose confirms the applicability of Fick's law of diffusion in describing the behavior of dextran. Under static loading, the application of compressive strain decreased the total interstitial volume available for the 70 kDa dextran, compared to free swelling. Dynamic loading significantly enhanced the rate of solute uptake into agarose disks, relative to static loading. Moreover, the steady-state concentration under dynamic loading was found to be significantly greater than under static loading, for larger-molecular-mass dextran (70 kDa). This experimental finding confirms recent theoretical predictions that mechanical pumping of a porous tissue may actively transport solutes into the disk against their concentration gradient. The results of this study support the hypothesis that the application of dynamic loading in the presence of growth factors of large molecular weight may result in both a mechanically and chemically stimulating environment for tissue growth.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2726307 | PMC |
http://dx.doi.org/10.1016/j.bpj.2009.05.047 | DOI Listing |
AAPS PharmSciTech
January 2025
Department of Pharmaceutical Sciences and Technology, Maharaja Ranjit Singh Punjab Technical University (MRSPTU), Bathinda, 151001, Punjab, India.
Microneedles (MNs) appear as a transformative and minimally invasive platform for transdermal drug delivery, representing a highly promising strategy in wound healing therapeutics. This technology, entailing the fabrication of micron-scale needle arrays, enables the targeted and efficient delivery of bioactive agents into the epidermal and dermal layers without inducing significant pain or discomfort. The precise penetration of MNs facilitates localized and sustained drug release, which significantly enhances tissue regeneration and accelerates wound closure.
View Article and Find Full Text PDFCarbohydr Polym
March 2025
School of Materials Science and Engineering, China University of Petroleum (East China), Qingdao 266580, China; Institute of Advanced Materials, China University of Petroleum (East China), Qingdao 266580, China.
Research on stimuli-responsive micro-nanocontainers has gained attention for targeted corrosion inhibition and controlled emulsification-demulsification in oil recovery. However, existing nanocontainers face issues like irreversible drug release and limited functionality. This study presents a multi-functional nanocontainer design with reversible drug release and emulsification-demulsification capabilities.
View Article and Find Full Text PDFJ Chiropr Med
December 2024
Department of Sports, Postgraduate Program in Physical Education, Federal University of Espirito Santo, Vitoria, Espirito Santo, Brazil.
Objective: : The purpose of this study was to characterize the dynamic distribution of training loads in a kettlebell program and evaluate its effects on muscle strength and aerobic capacity.
Methods: Fourteen recreationally active women with no kettlebell training experience (age: 25.86 ± 5.
Theranostics
January 2025
Beijing Key Laboratory of Molecular Pharmaceutics and Drug Delivery Systems, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China.
Radiofrequency ablation (RFA), as a minimally invasive surgery strategy based on local thermal-killing effect, is widely used in the clinical treatment of multiple solid tumors. Nevertheless, RFA cannot achieve the complete elimination of tumor lesions with larger burden or proximity to blood vessels. Incomplete RFA (iRFA) has even been validated to promote residual tumor growth due to the suppressive tumor immune microenvironment (TIME).
View Article and Find Full Text PDFJ Biochem
January 2025
Department of Molecular Biology, Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
For bidirectional replication in E. coli, higher-order complexes are formed at the replication origin oriC by the initiator protein DnaA, which locally unwinds the left edge of oriC to promote the loading of two molecules of DnaB onto the unwound region via dynamic interactions with the helicase-loader DnaC and the oriC-bound DnaA complex. One of the two helicases must translocate rightwards through oriC-bound DnaA complex.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!