Echocardiography, Transesophageal ; Humans ; Monitoring, Physiologic ; standards ; Pulmonary Circulation ; physiology ; Pulmonary Wedge Pressure ; Stroke Volume

Objective: The aim of this study was to introduce a gelatin/bovine serum albumin (BSA) tissue standard, which provides dissolution properties identical to those of biological tissues. Further, the study evaluated whether the utilization of endodontic activating devices led to enhanced phantom dissolution rates. Materials and Methods: Bovine pulp tissue was obtained to determine a benchmark of tissue dissolution. The surface area and mass of samples were held constant while the ratio of gelatin and BSA were varied, ranging from 7.5% to 10% gelatin and 5% BSA. Each sample was placed in an individual test tube that was filled with an appropriate sodium hypochlorite solution for 1, 3, and 5 minutes, and then removed from the solution, blotted dry, and weighed again. The remaining tissue was calculated as the percent of initial tissue to determine the tissue dissolution rate. A radiopaque agent (sodium diatrizoate) and a fluorescent dye (methylene blue) were added to the phantom to allow easy quantification of phantom dissolution in a canal block model when activated using ultrasonic (EndoUltra) or sonic (EndoActivator) energy. Results: The 9% gelatin + 5% BSA phantom showed statistically equivalent dissolution to bovine pulp tissue at all time intervals. Furthermore, the EndoUltra yielded significantly more phantom dissolution in the canal block than the EndoActivator or syringe irrigation. Conclusions Our phantom is comparable to biological tissue in terms of tissue dissolution and could be utilized for in vitro tests due to its injectability and detectability.

Objective: The aim of this study was to introduce a gelatin/bovine serum albumin (BSA) tissue standard, which provides dissolution properties identical to those of biological tissues. Further, the study evaluated whether the utilization of endodontic activating devices led to enhanced phantom dissolution rates. Materials and Methods: Bovine pulp tissue was obtained to determine a benchmark of tissue dissolution. The surface area and mass of samples were held constant while the ratio of gelatin and BSA were varied, ranging from 7.5% to 10% gelatin and 5% BSA. Each sample was placed in an individual test tube that was filled with an appropriate sodium hypochlorite solution for 1, 3, and 5 minutes, and then removed from the solution, blotted dry, and weighed again. The remaining tissue was calculated as the percent of initial tissue to determine the tissue dissolution rate. A radiopaque agent (sodium diatrizoate) and a fluorescent dye (methylene blue) were added to the phantom to allow easy quantification of phantom dissolution in a canal block model when activated using ultrasonic (EndoUltra) or sonic (EndoActivator) energy. Results: The 9% gelatin + 5% BSA phantom showed statistically equivalent dissolution to bovine pulp tissue at all time intervals. Furthermore, the EndoUltra yielded significantly more phantom dissolution in the canal block than the EndoActivator or syringe irrigation. Conclusions Our phantom is comparable to biological tissue in terms of tissue dissolution and could be utilized for in vitro tests due to its injectability and detectability.

Background: Early reports have indicated a relationship between ABO and rhesus blood group types and infection with SARS-CoV-2. We aim to examine blood group type associations with COVID-19 mortality and disease severity. Methods: This is a retrospective chart review of patients ages 18 years or older admitted to the hospital with COVID-19 between January 2020 and December 2021. The primary outcome was COVID-19 mortality with respect to ABO blood group type. The secondary outcomes were 1. Severity of COVID-19 with respect to ABO blood group type, and 2. Rhesus factor association with COVID-19 mortality and disease severity. Disease severity was defined by degree of supplemental oxygen requirements (ambient air, low-flow, high-flow, non-invasive mechanical ventilation, and invasive mechanical ventilation). Results: The blood type was collected on 596 patients with more than half (54%, N=322) being O+. The ABO blood type alone was not statistically associated with mortality (P=0.405), while the RH blood type was statistically associated with mortality (P＜0.001). There was statistically significant association between combined ABO and RH blood type and mortality (P=0.014). Out of the mortality group, the O+ group had the highest mortality (52.3%), followed by A+ (22.8%). The combined ABO and RH blood type was statistically significantly associated with degree of supplemental oxygen requirements (P =0.005).The Kaplan-Meier curve demonstrated that Rh- patients had increased mortality. Conclusion ABO blood type is not associated with COVID-19 severity and mortality. Rhesus factor status is associated with COVID-19 severity and mortality. Rhesus negative patients were associated with increased mortality risk.