Publications by authors named "Jordan Katz"

Infection associated with tissue-contacting biomedical devices is a compelling clinical problem initiated by the microbial colonization of the device surface. Among the possible sources of contaminating bacteria is the operating room (OR) itself, where viable bacteria in the atmosphere can sediment onto a device surface intraoperatively. We have developed an aerosolizing system that can reproducibly spray small quantities of aerosolized bacteria onto a surface to mimic OR contamination.

View Article and Find Full Text PDF

Background: Endoscopic submucosal dissection (ESD) and transanal endoscopic microsurgery (TEM) are minimally invasive procedures that treat early rectal cancer (ERC). Both are effective treatments, yet there are very few studies comparing them. The aim of our study was to identify ideal candidates for each procedure.

View Article and Find Full Text PDF

The most common risk associated with intradiscal injection of platelet-rich plasma (PRP) is discitis with . It is hypothesized that antimicrobial activity of PRP can be enhanced through inclusion of leukocytes or antibiotics in the injectate. Multiple PRP preparations of varying platelet and leukocyte counts were co-cultured with with or without cefazolin, with viable bacterial colony counts being recovered at 0, 4, 24 and 48 hours post-inoculation.

View Article and Find Full Text PDF

Transcatheter tricuspid valve-in-valve replacement via right internal jugular is safe and feasible for failed bioprosthetic valve implantation. Challenging aspects include stiff wire advancement into the pulmonary artery for rail establishment and multiple push-pull manipulations for balloon and valve advancement.

View Article and Find Full Text PDF

An emerging area in chemical science is the study of solid-phase redox reactions using ultrafast time-resolved spectroscopy. We have used molecules of the photoactive dye 2',7'-dichlorofluorescein (DCF) anchored to the surface of iron(III) oxide nanoparticles to create iron(II) surface atoms via photo-initiated interfacial electron transfer. This approach enables time-resolved study of the fate and mobility of electrons within the solid phase.

View Article and Find Full Text PDF

Reactions taking place at hydrated metal oxide surfaces are of considerable environmental and technological importance. Surface-sensitive X-ray methods can provide structural and chemical information on stable interfacial species, but it is challenging to perform in situ studies of reaction kinetics in the presence of water. We have implemented a new approach to creating a micrometer-scale water film on a metal oxide surface by combining liquid and gas jets on a spinning crystal.

View Article and Find Full Text PDF

Electron mobility within iron (oxyhydr)oxides enables charge transfer between widely separated surface sites. There is increasing evidence that this internal conduction influences the rates of interfacial reactions and the outcomes of redox-driven phase transformations of environmental interest. To determine the links between crystal structure and charge-transport efficiency, we used pump-probe spectroscopy to study the dynamics of electrons introduced into iron(III) (oxyhydr)oxide nanoparticles via ultrafast interfacial electron transfer.

View Article and Find Full Text PDF

Cameron lesions are linear erosions located at the neck of a hiatal hernia (HH) in patients with a large HH. The prevalence has been seen in up to 5% of patients with HH who undergo esophagogastroduodenoscopy, and they can be associated with overt gastrointestinal bleeding or anemia. These lesions occur due to vascular compression by the diaphragm in a large sliding HH.

View Article and Find Full Text PDF

Infected bone defects and osteomyelitis are encountered frequently in trauma cases. Currently, the standard of care for osteomyelitis cases is prolonged systemic antibiotic therapy and implantation of antibiotic carrier beads. However, this method requires a secondary surgery to remove the beads after the infection has cleared.

View Article and Find Full Text PDF

Bone graft substitutes have been developed due to the limited supply and morbidity associated with using autogenous graft material. Allogeneic demineralized bone matrix (DBM) has been used extensively as a clinical graft material because of its inherent osteoinductive and osteoconductive properties. Differential enhancement of these properties may optimize the performance of these products for various orthopedic and craniofacial applications.

View Article and Find Full Text PDF

This study was conducted to determine if a novel cleaning process could extract antigenic material from bovine bone thereby improving incorporation. Cleaned bovine xenograft, untreated bovine xenograft and sheep allograft were implanted into the tibia of mature sheep for 12 and 24 weeks. Inflammation, bone integration and immunological reactions were evaluated via standardized assays.

View Article and Find Full Text PDF

The osteoinductivity of demineralized bone matrix (DBM) varies from donor to donor as a result of varying levels of multiple growth factors, matrix integrity, and artifacts from material processing. Many in vitro assays are currently used for screening the osteoinductivity of DBM. The objectives of this study were to determine the correlation of specific growth factors and in vitro mitotic stimulation to in vivo ectopic bone formation capacity with a large number of DBM samples.

View Article and Find Full Text PDF

Gene delivery from tissue-engineering devices has the potential to improve healing, but better regulation of the level and duration of gene expression is needed. We hypothesized that transgene expression could be controlled by varying the fabrication and soaking parameters used in making collagen- based gene delivery scaffolds. Collagen films were made from acid-insoluble type I bovine dermal collagen and seeded with plasmid DNA encoding firefly luciferase, complexed with polyethylenimine.

View Article and Find Full Text PDF

False aneurysms of the mitral-aortic intervalvular fibrosa are rare and usually complicate aortic valve endocarditis. We report a case of a false aneurysm of the mitral-aortic intervalvular fibrosa after recent bioprosthetic aortic valve replacement in the absence of endocarditis.

View Article and Find Full Text PDF