Recent studies have shown that mesenchymal stem cells (MSC) with the potential for cell-mediated therapies and tissue engineering applications can be isolated from extracted dental tissues. Here, we investigated the collection, processing, and cryobiological characteristics of MSC from human teeth processed under current good tissue practices (cGTP). Viable dental pulp-derived MSC (DPSC) cultures were isolated from 31 of 40 teeth examined. Of eight DPSC cultures examined more thoroughly, all expressed appropriate cell surface markers and underwent osteogenic, adipogenic, and chondrogenic differentiation in appropriate differentiation medium, thus meeting criteria to be called MSC. Viable DPSC were obtained up to 120 h postextraction. Efficient recovery of DPSC from cryopreserved intact teeth and second-passage DPSC cultures was achieved. These studies indicate that DPSC isolation is feasible for at least 5 days after tooth extraction, and imply that processing immediately after extraction may not be required for successful banking of DPSC. Further, the recovery of viable DPSC after cryopreservation of intact teeth suggests that minimal processing may be needed for the banking of samples with no immediate plans for expansion and use. These initial studies will facilitate the development of future cGTP protocols for the clinical banking of MSC.

Dental pulp is a promising source of mesenchymal stem cells with the potential for cell-mediated therapies and tissue engineering applications. We recently reported that isolation of dental pulp-derived stem cells (DPSC) is feasible for at least 120 hours after tooth extraction, and that cryopreservation of early-passage cultured DPSC leads to high-efficiency recovery post thaw. This study investigated additional processing and cryobiological characteristics of DPSC, ending with development of procedures for banking. First, we aimed to optimize cryopreservation of established DPSC cultures, with regards to optimizing the cryoprotective agent (CPA), the CPA concentration, the concentration of cells frozen, and storage temperatures. Secondly, we focused on determining cryopreservation characteristics of enzymatically digested tissue as a cell suspension. Lastly, we evaluated the growth, surface markers and differentiation properties of DPSC obtained from intact teeth and undigested, whole dental tissue frozen and thawed using the optimized procedures. In these experiments it was determined that Me2SO at a concentration between 1 and 1.5M was the ideal cryopreservative of the three studied. It was also determined that DPSC viability after cryopreservation is not limited by the concentration of cells frozen, at least up to 2 × 106 cells/mL. It was further established that DPSC can be stored at −85°C or −196°C for at least six months without loss of functionality. The optimal results with the least manipulation were achieved by isolating and cryopreserving the tooth pulp tissues, with digestion and culture performed post-thaw. A recovery of cells from >85% of the tissues frozen was achieved and cells isolated post thaw from tissue processed and frozen with a serum free, defined cryopreservation medium maintained morphological and developmental competence and demonstrated MSC-hallmark trilineage differentiation under the appropriate culture conditions.

The pathophysiology of hepatic ischemia/reperfusion injury (IRI) includes a number of complex and diverse mechanisms involving interactions between hepatocytes, Kupffer cells, neutrophils, macrophages, sinusoidal endothelial cells, and platelets. Tumor Necrosis Factor-α (TNF-α), a cytokine produced by numerous cell types in response to inflammatory stimuli, is a well-known mediator during ischemia/reperfusion (IR) that plays a central role in injury to hepatocytes. TNF-α has a multifactorial effect in hepatic IRI because of the many interactions between TNF-α and reactive oxygen species, nitric oxide, adhesion molecules, and various cytokines and chemokines. The intracellular cascades that TNF-α triggers and their downstream effects are clearly presented throughout this manuscript. With these mechanisms in mind, ischemic preconditioning and pharmacological interventions with potential clinical application to prevent or attenuate IRI will be emphasized.

Fluoroscopic CBCT guidance for percutaneous osteoid osteoma ablation yields similar technical and clinical success, reduced radiation dose, and increased total room utilization time compared to conventional CT guidance.

Purpose Assess national trends in utilization, demographics, hospital characteristics, and outcomes of patients undergoing surgical or percutaneous portal decompression since the introduction of the transjugular intrahepatic portosystemic shunt (TIPS). Materials/Methods Retrospective analysis of patients undergoing surgical portal decompression and TIPS using Medicare Physician Supplier Procedure Summary files from January 2003 through December 2013 and National/Nationwide Inpatient Sample data from 1993, 2003, and 2012. Utilization rates normalized to annual number of Medicare enrollees, estimated means, and 95% confidence intervals were calculated. Results Medicare total annual utilization rate for all portosystemic decompression procedures decreased 6.5% during the study period, from 15.3 in 2003 to 14.3 in 2013 per 1,000,000. TIPS utilization increased 19.4% (10.3 to 12.3 per 1,000,000) while open surgical shunt utilization decreased by 60.0% (5.0 to 2.0 per 1,000,000). TIPS represented 86% of all procedures in 2013. From 1993 to 2012, mean age increased slightly (53.0 to 55.5 years, p-value <0.05). The percentage of procedures performed at teaching hospitals increased, while in-hospital mortality and length of stay decreased by 42% (p<0.05) and 20% (p<0.05), respectively. Of factors evaluated, performance of procedures on an elective basis was the most influential on in-hospital mortality (p<0.01, all years studied) and length of stay (p<0.0001, all years studied). Conclusions Approximately two decades following the introduction of TIPS, utilization of all portal decompression procedures has remained relatively stable. TIPS represents the dominant portal decompression technique. In-hospital mortality and mean length of stay following decompression have decreased, partially due to performance of procedures during elective admissions.