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Injectable hydrogels are a sub-type of hydrogels which can be delivered into the host in a minimally invasive manner. They can act as carriers to encapsulate and deliver cells, drugs or active biomolecules across several disease conditions. Polymers, either synthetic or natural, or even a combination of the two, can be used to create injectable hydrogels. Clinically approved injectable hydrogels are being used as dressings for burn wounds, bone and cartilage reconstruction. Injectable hydrogels have recently gained tremendous attention for their delivery into the liver in pre-clinical models. However, their efficacy in clinical studies remains yet to be established. In this article, we describe principles for the design of these injectable hydrogels, delivery strategies and their potential applications in facilitating liver regeneration and ameliorating injury. We also discuss the several constraints related to translation of these hydrogels into clinical settings for liver diseases and deliberate some potential solutions to combat these challenges., (© 2024 Wiley-VCH GmbH.)

When acquiring accurate ultrasonic images, we must precisely estimate the mechanical properties of the soft tissue. This study investigates and estimates the viscoelastic properties of the tissue by analyzing shear waves generated through an acoustic radiation force. The shear waves are sourced from a localized pushing force acting for a certain duration, and the generated waves travel horizontally. The wave velocities depend on the mechanical properties of the tissue such as the shear modulus and viscoelastic properties; therefore, we can inversely calculate the properties of the tissue through parametric studies. [ABSTRACT FROM AUTHOR]

Tissue decellularization has rapidly developed to be a practical approach in tissue engineering research; biological tissue is cleared of cells resulting in a protein-rich husk as a natural scaffold for growing transplanted cells as a donor organ therapy. Minimally processed, acellular extracellular matrix reproduces natural interactions with cells in vitro and for tissue engineering applications in animal models. There are many decellularization techniques that achieve preservation of molecular profile (proteins and sugars), microstructure features such as organization of ECM layers (interstitial matrix and basement membrane) and organ level macrofeatures (vasculature and tissue compartments). While structural and molecular cues receive attention, mechanical and material properties of decellularized tissues are not often discussed. The effects of decellularization on an organ depend on the tissue properties, clearing mechanism, chemical interactions, solubility, temperature, and treatment duration. Physical characterization by a few labs including work from the authors provides evidence that decellularization protocols should be tailored to specific research questions. Physical characterization beyond histology and immunohistochemistry of the decellularized matrix (dECM) extends evaluation of retained functional features of the original tissue. We direct our attention to current technologies that can be employed for structure function analysis of dECM using underutilized tools such as atomic force microscopy (AFM), cryogenic electron microscopy (cryo-EM), dynamic mechanical analysis (DMA), Fourier-transform infrared spectroscopy (FTIR), mass spectrometry, and rheometry. Structural imaging and mechanical functional testing combined with high-throughput molecular analyses opens a new approach for a deeper appreciation of how cellular behavior is influenced by the isolated microenvironment (specifically dECM). Additionally, the impact of these features with different decellularization techniques and generation of synthetic material scaffolds with desired attributes are informed. Ultimately, this mechanical profiling provides a new dimension to our understanding of decellularized matrix and its role in new applications. [ABSTRACT FROM AUTHOR]

Tissue perfusion is essential for transporting blood oxygen and nutrients. Measurement of tissue perfusion rate would have a significant impact in clinical and preclinical arenas. However, there are few techniques to image this important parameter and they typically require contrast agents. A label-free methodology based on tissue compression and imaging with a high-frequency photoacoustic-ultrasound system is introduced for estimating and visualizing tissue perfusion rates. Experiments demonstrate statistically significant differences in depth-resolved perfusion rates in a human subject with various temperature exposure conditions. [ABSTRACT FROM AUTHOR]

HisTOOLogy is an open-source software for the quantification of digital colour images of histological sections. The simple graphical user interface enables both expert and non-expert users to rapidly extract useful information from stained tissue sections. The software's main feature is a generalizable colour separation algorithm based on k-means clustering which accurately and reproducibly returns the amount of colour per unit area for any stain, thus allowing the quantification of tissue components. Here we describe HisTOOLogy's algorithms and graphical user interface structure, showing how it can be used to separate different dye colours inseveral classical stains. In addition, to demonstrate how the tool can be employed to obtain quantitative informationonbiological tissues, the effect of different hepatic tissue decellularization protocols on cell removal and matrix preservation was assessed through image analysis using HisTOOLogy and compared with conventional DNA and total protein content assays. HisTOOLogy's performancewasalso compared with ImageJ's colour deconvolution plug-in, demonstrating its advantages in terms of ease of use and speed of colour separation. [ABSTRACT FROM AUTHOR]

Simple Summary: The Sardo-Modicana is a local cattle breed from Sardinia, Italy. It originated from the crossing of Sardinian local cows with Modicana bulls from Sicily, imported in the late 19th century. In the 1950s, approximately 60,000 heads were present, but nowadays the total population has decreased to about 1800 animals. It is a multipurpose breed, and animals are farmed using extensive methods. Traditionally, cows are hand-milked and milk is destined to produce a traditional pasta filata cheese. In the literature, the information about the dairy potential of this breed is scarce. The present study evidenced the favorable genetic patterns, milk composition and coagulation traits of the Sardo-Modicana cattle breed; such information will be useful for the preservation and enhancement of the breed. The Sardo-Modicana is a local cattle breed from Sardinia, Italy. No information about its dairy potential is available in the literature. This study investigated the genotype at the CSN3 gene and milk traits of the Sardo-Modicana cattle breed. Fifty-four cows were sampled for DNA extraction and genotyping at the κ-casein gene locus, CSN3. Forty individual milk samples were analyzed for milk composition, milk coagulation properties and cheese yield (CY%). All the Sardo-Modicana cows were BB homozygotes at CSN3. Hence, the results were compared with the other two local Sardinian breeds. Eighty-three Sarda and 21 Sardo-Bruna cows were genotyped, and the A allele was found (at frequencies of 0.416 and 0.405, respectively). As regards milk traits, the mean protein value was 3.74 g/100 mL, and the mean casein value was 2.98 g/100 mL. Total bacterial and somatic cell counts showed excellent levels of hygiene considering the extensive farming and hand milking. In addition, milk produced by Sardo-Modicana cows was characterized by favorable values of coagulation properties and cheese yield. This information may represent a starting point for the conservation and enhancement of this breed. [ABSTRACT FROM AUTHOR]

Development of mechanically deformable solid state devices is receiving tremendous attention, and high ionic conductivity solid polymer electrolytes (SPEs) are highly sought after for their development. The process history‐induced polymer alignment anisotropy can lead to anisotropic conductivity to the SPEs. Here, a Li ion SPE membrane developed using poly(ethylene oxide) (PEO) and LiClO4 is demonstrated for its microstructure variations while applying external stress and the corresponding variations in the ionic conductivity are also calculated. The microstructural evolution shows that larger strain values induce large dislocations in the crystallites of PEO leading to the formation of larger amorphous regions which soften the matrix. The anisotropic mechanical responses are observed while applying cyclic strain to thicker SPEs, where the compressive measurements show softening of the matrix while tensile measurements harden the matrix. The ionic conductivities of the softened matrix are found to be enhanced while those of toughened matrix are found to be decreased. This detailed mechanical analysis along with the in situ ionic conductivity studies of PEO‐based Li ion SPE show that along with the thermal history of the polymers, process history and the anisotropic mechanical responses of the polymers also need to be considered while developing SPEs for flexible devices. [ABSTRACT FROM AUTHOR]