Controlling cellular packing and hypoxia in 3D tumor spheroids DNA interactions.

Tumor spheroids represent valuable models for studying cancer biology and evaluating therapeutic strategies. In this study, we investigated the impact of varying lengths of DNA-modified cell surfaces on spheroid formation, cellular adhesion molecule expression, and hypoxia levels within 4T1 mouse breast cancer spheroids. Through a series of experiments, we demonstrated that modifying cell surfaces with biotinylated DNA strands of different lengths facilitated spheroid formation without significantly altering the expression of fibronectin and e-cadherin, key cellular adhesion molecules.

Controlling Cell Organization in 3D Coculture Spheroids Using DNA Interactions.

The role of stromal and immune cells in transforming the tumor microenvironment is a key consideration in understanding tumor cell behavior and anticancer drug development. To better model these systems in vitro, 3D coculture tumor spheroids have been engineered using a variety of techniques including centrifugation to microwells, hanging drop, low adhesion cultures, and culture of cells in a microfluidic platform. Aside from using bioprinting, however, it has remained more challenging to direct the spatial organization of heterotypic cells in standalone 3D spheroids.

Anatomic CAD-CAM post-and-core systems: A mastication simulation study.

Statement Of Problem: Few studies have investigated the differences among various post-and-core systems under mastication simulation. Comparing these systems while simulating the clinical environment should provide a more accurate assessment of their performance.

Purpose: The purpose of this in vitro study was to evaluate the fatigue resistance of conventional cast metal and prefabricated fiber post systems with computer-aided design and computer-aided manufacture (CAD-CAM) prefabricated nonmetal post-and-core systems.

Outcome Assessment of Teeth with Necrotic Pulps and Apical Periodontitis Treated with Long-term Calcium Hydroxide.

Introduction: The aim of this retrospective, cohort case series was 2-fold: (1) to evaluate the outcomes of teeth with necrotic pulps and apical periodontitis using long-term calcium hydroxide (Ca[OH]) (healing was assessed via the periapical index [PAI] system) and (2) to explore the possible association of fractures in relation to long term Ca(OH) exposure.

Methods: A total of 242 cases, diagnosed with pulpal necrosis and apical periodontitis, were treated with long-term Ca(OH) using a standardized protocol. Injectable and powdered Ca(OH) were placed sequentially in the root canal system.

Periapical Microsurgery: Assessment of Different Types of Light-emitting Diode Transilluminators in Detection of Dentinal Defects.

Introduction: This study evaluated 4 different light-emitting diode (LED) transilluminators and the impact of operator experience in the detection of dentinal defects through an ex vivo TRUEJAW surgical model (Dental Engineering Laboratories, Santa Barbara, CA).

Methods: Forty-four extracted and endodontically treated mandibular premolar teeth were evaluated. Teeth were mounted in the models followed by surgical flaps and osteotomies to expose the apical third of the roots.