Concomitant Heart and Lung Surgery During Lung Transplantation.

INTRODUCTION: There is limited data concerning concomitant cardiac and lung surgery outcomes during lung transplantation (LTx). While some evidence suggests that cardiac surgery during LTx has no significant impact on surgical outcomes, scarce data examines the role of concomitant lung surgery (CLS). This study compares the survival outcomes of concomitant cardiac and lung surgeries during LTx. METHODS: A retrospective analysis of all single and double LTx patients from March 2012 to June 2023 at a single center was performed (n = 1099). Patients were stratified into three concomitant surgical groups: concomitant cardiac surgery (CCS), CLS, and no concomitant surgeries. Groups were compared on recipient demographics, diagnosis, and surgical intervention using analysis of variance and chi-square tests. Survival (5 y) was analyzed using Kaplan-Meier curves, log-rank test, and univariable Cox proportional hazard model where P value <0.05 was considered significant. RESULTS: In total, 1099 patients were analyzed in this study; 965 had no concomitant surgery, 100 had CCS (mode: coronary artery bypass grafting, n = 75), and 34 had CLS (mode: lung volume reduction surgery, n = 14). Between the three surgical groups, there was no significant difference in body mass index (P = 0.091), total ischemic time (P = 0.194), induction (P = 0.140), or cause of death (P = 0.240). Lung allocation score and length of stay were significantly higher in the concomitant surgical groups, especially the CLS group when compared to the no concomitant surgery group (P = 0.002, P = 004). Patients with no concomitant surgery had a higher incidence of single LTx and off-pump utilization than concomitant surgical groups (P < 0.001). Kaplan-Meier curves and log-rank tests found no significant difference in survival between groups (P = 0.849). This result is supported by Cox proportional hazard model with no significant difference in mortality risk between the CCS group (P = 0.522) and CLS group (P = 0.936) compared to no concomitant surgery during LTx. CONCLUSIONS: Our study provides promising data indicating that individuals undergoing concomitant heart or lung surgery during LTx have similar survival outcomes to those exclusively undergoing LTx. These results highlight the potential advantages of utilizing LTx to address concurrent thoracic surgical needs, such as coronary revascularization. This holds implications for optimizing patient care and decision-making when complex thoracic interventions are necessary.

Carbonate substitution significantly affects the structure and mechanics of carbonated apatites.

Bone mineral comprises nanoparticles of carbonate-substituted bioapatite similar to hydroxylapatite. Yet mechanical values of macroscopic-sized geological hydroxylapatite are often used to model bone properties due to a lack of experimental data for bioapatite. Here, we investigated the effects of carbonate substitution and hydration on biomimetic apatite response to load using in situ hydrostatic pressure loading and synchrotron x-ray diffraction. We find that increasing carbonate levels reduced the bulk modulus and elastic strain ratio. Elastic constants, determined using computational optimization techniques, revealed that compliance values and elastic moduli decreased with increasing carbonate content, likely a result of decreased bond strength due to CO32- substitution and Ca2+ loss. Hydration environment had no clear effects on the elastic properties likely due to dissolution and reprecipitation processes modifying the crystal structure organization. These results reinforce the need to consider carbonate composition when selecting mechanical properties and provide robust data for carbonate-substituted apatite stiffness.

Mechanism for enhancement of visible light response on nitrogen-doped TiO2 by modification with vanadium species.

Photocatalytic activities of nitrogen-doped TiO2 (N-TiO2) will remarkably increase by surface modification with vanadium (+V) species for the decomposition of volatile organic compounds (VOCs) in the presence of O2 under visible light irradiation. Study on the electron spin resonance (ESR) shows that the vanadium (+V) species interacted with N-TiO2 surface is photo-reduced to form vanadium (+IV) in vacuum or in the presence of hole scavengers under visible light irradiation, and subsequently, it is re-oxidized into vanadium (+V) by O2. Furthermore, the concentration of visible light induced holes (.N radicals) on V-oxide/N-TiO2 is much higher than that on N-TiO2. Therefore, it is confirmed that the added vanadium species having oxidation states between +IV and +V that interact with surface N-TiO2 play significant roles as redox mediators in the effective charge separation of holes and electrons, which consequently brings about an enhancement of photocatalytic activity.