Genome concentration limits cell growth and modulates proteome composition in .

Defining the cellular factors that drive growth rate and proteome composition is essential for understanding and manipulating cellular systems. In bacteria, ribosome concentration is known to be a constraining factor of cell growth rate, while gene concentration is usually assumed not to be limiting. Here, using single-molecule tracking, quantitative single-cell microscopy, and modeling, we show that genome dilution in cells arrested for DNA replication limits total RNA polymerase activity within physiological cell sizes across tested nutrient conditions.

Photon-counting in dual-contrast-enhanced computed tomography: a proof-of-concept quantitative biomechanical assessment of articular cartilage.

This proof-of-concept study explores quantitative imaging of articular cartilage using photon-counting detector computed tomography (PCD-CT) with a dual-contrast agent approach, comparing it to clinical dual-energy CT (DECT). The diffusion of cationic iodinated CA4 + and non-ionic gadolinium-based gadoteridol contrast agents into ex vivo bovine medial tibial plateau cartilage was tracked over 72 h. Continuous maps of the contrast agents' diffusion were created, and correlations with biomechanical indentation parameters (equilibrium and instantaneous moduli, and relaxation time constants) were examined at 28 specific locations.

Comparison of site-specific tensile, compressive, and friction properties of human tibiofemoral joint cartilage and their relationship to degeneration.

Site-specific differences in the compressive properties of tibiofemoral joint articular cartilage are well-documented, while exploration of tensile and frictional properties in humans remains limited. Thus, this study aimed to characterize and compare the tensile, compressive and frictional properties of articular cartilage across different sites of the tibiofemoral joint, and to establish relationships between these properties and cartilage degeneration. We cut human tibiofemoral joint (N = 5) cartilage surfaces into tensile testing samples (n = 155) and osteochondral plugs (n = 40) to determine the tensile, friction and compressive properties, as well as OARSI grades.

Imatinib decreases germ cell survival and germline stem cell proliferation in rodent testis ex vivo and in vitro.

Background: Imatinib and dasatinib are tyrosine kinase inhibitors (TKIs) increasingly used to treat several diseases in both children and adults at fertile age. We have previously shown that imatinib has adverse effects on developing testis, and imatinib-treated male patients have been reported to have reduced sperm counts. However, the cellular level effects of imatinib and dasatinib on adult male germ cells and germline stem cells (mGSCs) have not been thoroughly investigated.