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Marine Biopolymers
Published in Se-Kwon Kim, Marine Biochemistry, 2023
One of the important requirements of the scaffold is the architecture for how to mimic the natural hierarchy of the natural tissue. Nowadays, with the 3D printing technique, the scientists can obtain the microstructure following the design (Alison et al., 2019). In addition, by integrating with the sacrificial template technique, the porosity and pore size of scaffold can be controlled. In this method, the sacrificial template is made by polymer like polylacid polymer (PLA) via 3D printing technique for obtaining fiber template. The solution of chitosan in acetic acid was inhaled to fill the void space in the template. After freeze-drying, the chitosan will cover the fiber of PLA. The dichloromethane (DMC) is used to dissolve the PLA, which means all the template is removed (scarified) and leaves the porous chitosan scaffold (Jiang et al., 2021). For high activities in biomedicine, the chitosan used in these studies has a high degree of deacetylation (>90%).
Principles behind Magnetic Resonance Imaging (MRI)
Published in Michael Ljungberg, Handbook of Nuclear Medicine and Molecular Imaging for Physicists, 2022
Magnetic resonance imaging (MRI) is a well-established medical imaging technique, traditionally associated with excellent soft-tissue contrast properties. Current clinical MRI systems provide not only morphological information throughout the body, but also a number of advanced techniques related to tissue and organ function, physiology, and microstructure.
Functional Foods: Bioavailability, Structure, and Nutritional Properties
Published in Hafiz Ansar Rasul Suleria, Megh R. Goyal, Health Benefits of Secondary Phytocompounds from Plant and Marine Sources, 2021
Tawheed Amin, H. R. Naik, Syed Zameer Hussain, Bazila Naseer
This chapter suggests that the food microstructure modulates various physiological functions inside our body and also plays detrimental or beneficial roles in some diet-related diseases. It is also concluded that the microstructure affects the nutritional composition as well. Bridging food structuring and the physiology of the gastrointestinal tract (GIT), along with the development of the methods for non-obstructive estimation/measurement and interdisciplinary research will offer the basis for the design and development of novel and future food products with a tailor-made useful behavior within the human frame. Such food products may have the potential to overcome the problem of weight loss. While developing food products for specific health, wellness, and nutritional needs, it is important to adapt the food structure. From the harvesting of raw material to its consumption stage, food structure gets changed. Hence, an exhaustive understanding of these time-dependent changes is needed.
Synthetic biodegradable polyesters for implantable controlled-release devices
Published in Expert Opinion on Drug Delivery, 2022
Jinal U. Pothupitiya, Christy Zheng, W. Mark Saltzman
Biodegradable polymeric implants are mostly produced in the form of reservoirs (cylindrical rods) or monolithic matrixes (films, wafers or cylindrical rods). In the case of a reservoir, a depot of drug molecules is surrounded by a polymeric barrier. In these implants, polymer degradation rate, implant manufacturing process, physiological properties of the implant insertion microenvironment, and rate of drug diffusion through the polymer barrier dictate drug-releasing capacity. In contrast, a monolithic implant comprises a drug-embedded polymer matrix, where the manufacturing process of the implant, drug dissolution, and diffusion through the polymer matrix primarily influence drug release. For implants with a dispersed drug phase, the microstructure of the material is critically important in determining the kinetics of drug release [97]. Therefore, control or manipulation of microstructure represents another important approach for achieving desired release kinetics [98]. The drug release profiles from implantable, biodegradable drug delivery systems are governed by diffusion of the drug, degradation of the polymer, and erosion of the material structure of the implant. Degradation and erosion are related events where the former is a chemical phenomenon and the latter a physical. Degradation of polyesters occurs via hydrolysis, which results in the formation of water-soluble oligomers and monomers, eventually leading to erosion (or loss of material structure) as the oligomers and monomers diffuse away from the implant (Figure 1).
Narrative intervention in school-aged children with autism spectrum disorder: a systematic review
Published in Speech, Language and Hearing, 2022
Joyce Yuen Ching Tam, Elizabeth Ann Barrett, Astrid Yuen Hin Ho
Microstructure. The effect of narrative intervention on the production of narrative microstructure was measured in one SCED (Petersen et al., 2014). It demonstrated a significant medium intervention effect for two measurements in a standardized test (n = 3, Tau-U = 0.599; CI [0.27, .93]) and (n = 3, Tau-U = 0.791; CI [0.40, 1]). Since only one study measured microstructure, the strength of evidence for the causal relationship could not be adequately evaluated. During data extraction, it was observed one SCED (Gillam et al., 2015) also included microstructure as an outcome measurement. The data was excluded from synthesis since the measurement in Monitoring Indicator of Scholarly Language (Gillam, Gillam, Fargo, Olszewski, & Segura, 2017) combined scores of macrostructure and microstructure to indicate overall narrative complexity. In order to prevent combining the results of a mix of constructs across studies, the effect size of the outcome construct of this study was not calculated. In terms of maintenance, the treatment gains were not maintained with negative Tau-U for both measurements (n = 3, Tau-U = −0.351; CI [−0.90, 0.20]) and (n = 3, Tau-U = −0.569; CI [−1, 0.01]).
Effect of roll compaction pressure on the properties of high drug-loaded piracetam granules and tablets
Published in Drug Development and Industrial Pharmacy, 2022
Microstructure plays a decisive role in the disintegration and drug release from the tablet [65]. The particle size of the roll compacted granules and the deformation of granules during tableting is influencing the water ingress into the tablet [66]. From another side, it’s logical to assume that the distribution of disintegrant in the tablet, which was produced from roll compacted granules at 4, 5 and 13 MPa was different. In the tablet mixture based on the roll compacted granules at 4 and 5 MPa vs. 13 MPa, the disintegrant should be distributed more evenly because of the smaller granule size. At the same time, in the tablet mixture based on the roll compacted granules at 13 MPa vs 4 and 5 MPa, the disintegrant clusters of disintegrant should be greater. Thus, considering the high solubility of piracetam, the faster disintegration time and drug release (Figure 10B) for tablets based on the roll compacted granules at 13 MPa vs 4 and 5 MPa, can be explained by the microstructure of tablets, higher disintegration force of disintegrant clusters, and faster water ingression into the tablet.