5-HT modulation of a medial septal circuit tunes social memory stability.

Social memory-the ability to recognize and remember familiar conspecifics-is critical for the survival of an animal in its social group1,2. The dorsal CA2 (dCA2)3-5 and ventral CA1 (vCA1)6 subregions of the hippocampus, and their projection targets6,7, have important roles in social memory. However, the relevant extrahippocampal input regions remain poorly defined. Here we identify the medial septum (MS) as a dCA2 input region that is critical for social memory and reveal that modulation of the MS by serotonin (5-HT) bidirectionally controls social memory formation, thereby affecting memory stability. Novel social interactions increase activity in dCA2-projecting MS neurons and induce plasticity at glutamatergic synapses from MS neurons onto dCA2 pyramidal neurons. The activity of dCA2-projecting MS cells is enhanced by the neuromodulator 5-HT acting on 5-HT1B receptors. Moreover, optogenetic manipulation of median raphe 5-HT terminals in the MS bidirectionally regulates social memory stability. This work expands our understanding of the neural mechanisms by which social interactions lead to social memory and provides evidence that 5-HT has a critical role in promoting not only prosocial behaviours8,9, but also social memory, by influencing distinct target structures.

Mitochondrial control of microglial phagocytosis by the translocator protein and hexokinase 2 in Alzheimer's disease.

Microglial phagocytosis is an energetically demanding process that plays a critical role in the removal of toxic protein aggregates in Alzheimer's disease (AD). Recent evidence indicates that a switch in energy production from mitochondrial respiration to glycolysis disrupts this important protective microglial function and may provide therapeutic targets for AD. Here, we demonstrate that the translocator protein (TSPO) and a member of its mitochondrial complex, hexokinase-2 (HK), play critical roles in microglial respiratory-glycolytic metabolism and phagocytosis. Pharmacological and genetic loss-of-function experiments showed that TSPO is critical for microglial respiratory metabolism and energy supply for phagocytosis, and its expression is enriched in phagocytic microglia of AD mice. Meanwhile, HK controlled glycolytic metabolism and phagocytosis via mitochondrial binding or displacement. In cultured microglia, TSPO deletion impaired mitochondrial respiration and increased mitochondrial recruitment of HK, inducing a switch to glycolysis and reducing phagocytosis. To determine the functional significance of mitochondrial HK recruitment, we developed an optogenetic tool for reversible control of HK localization. Displacement of mitochondrial HK inhibited glycolysis and improved phagocytosis in TSPO-knockout microglia. Mitochondrial HK recruitment also coordinated the inflammatory switch to glycolysis that occurs in response to lipopolysaccharide in normal microglia. Interestingly, cytosolic HK increased phagocytosis independent of its metabolic activity, indicating an immune signaling function. Alzheimer's beta amyloid drastically stimulated mitochondrial HK recruitment in cultured microglia, which may contribute to microglial dysfunction in AD. Thus, targeting mitochondrial HK may offer an immunotherapeutic approach to promote phagocytic microglial function in AD.

CellTracer: a comprehensive database to dissect the causative multilevel interplay contributing to cell development trajectories.

During the complex process of tumour development, the unique destiny of cells is driven by the fine-tuning of multilevel features such as gene expression, network regulation and pathway activation. The dynamic formation of the tumour microenvironment influences the therapeutic response and clinical outcome. Thus, characterizing the developmental landscape and identifying driver features at multiple levels will help us understand the pathological development of disease in individual cell populations and further contribute to precision medicine. Here, we describe a database, CellTracer (http://bio-bigdata.hrbmu.edu.cn/CellTracer), which aims to dissect the causative multilevel interplay contributing to cell development trajectories. CellTracer consists of the gene expression profiles of 1 941 552 cells from 222 single-cell datasets and provides the development trajectories of different cell populations exhibiting diverse behaviours. By using CellTracer, users can explore the significant alterations in molecular events and causative multilevel crosstalk among genes, biological contexts, cell characteristics and clinical treatments along distinct cell development trajectories. CellTracer also provides 12 flexible tools to retrieve and analyse gene expression, cell cluster distribution, cell development trajectories, cell-state variations and their relationship under different conditions. Collectively, CellTracer will provide comprehensive insights for investigating the causative multilevel interplay contributing to cell development trajectories and serve as a foundational resource for biomarker discovery and therapeutic exploration within the tumour microenvironment.

Evaluating the Impact of Operative Team Familiarity on Cardiac Surgery Outcomes: A Retrospective Cohort Study of Medicare Beneficiaries.

OBJECTIVE: To associate surgeon-anesthesiologist team familiarity (TF) with cardiac surgery outcomes. BACKGROUND: TF, a measure of repeated team member collaborations, has been associated with improved operative efficiency; however, examination of its relationship to clinical outcomes has been limited. METHODS: This retrospective cohort study included Medicare beneficiaries undergoing coronary artery bypass grafting (CABG), surgical aortic valve replacement (SAVR), or both (CABG+SAVR) between January 1, 2017, and September 30, 2018. TF was defined as the number of shared procedures between the cardiac surgeon and anesthesiologist within 6 months of each operation. Primary outcomes were 30- and 90-day mortality, composite morbidity, and 30-day mortality or composite morbidity, assessed before and after risk adjustment using multivariable logistic regression. RESULTS: The cohort included 113,020 patients (84,397 CABG; 15,939 SAVR; 12,684 CABG+SAVR). Surgeon-anesthesiologist dyads in the highest [31631 patients, TF median (interquartile range)=8 (6, 11)] and lowest [44,307 patients, TF=0 (0, 1)] TF terciles were termed familiar and unfamiliar, respectively. The rates of observed outcomes were lower among familiar versus unfamiliar teams: 30-day mortality (2.8% vs 3.1%, P =0.001), 90-day mortality (4.2% vs 4.5%, P =0.023), composite morbidity (57.4% vs 60.6%, P <0.001), and 30-day mortality or composite morbidity (57.9% vs 61.1%, P <0.001). Familiar teams had lower overall risk-adjusted odds of 30-day mortality or composite morbidity [adjusted odds ratio (aOR) 0.894 (0.868, 0.922), P <0.001], and for SAVR significantly lower 30-day mortality [aOR 0.724 (0.547, 0.959), P =0.024], 90-day mortality [aOR 0.779 (0.620, 0.978), P =0.031], and 30-day mortality or composite morbidity [aOR 0.856 (0.791, 0.927), P <0.001]. CONCLUSIONS: Given its relationship with improved 30-day cardiac surgical outcomes, increasing TF should be considered among strategies to advance patient outcomes.

Renal Dysfunction at Discharge and Long-Term Survival in Acute Type A Aortic Dissection.

INTRODUCTION: We aimed to investigate the association between renal dysfunction at discharge and long-term survival in acute type A aortic dissection (ATAAD) patients following surgery. METHODS: From 2000 to 2021, 784 patients underwent aortic repair for an ATAAD. Patients were stratified based on creatinine (Cr) level at discharge alive or dead: normal Cr (n = 582) and elevated Cr defined as >1.3 mg/dL for males and >1.0 mg/dL for females or on dialysis at discharge (n = 202). RESULTS: Preoperatively, both groups had similar rates of comorbidities except for the elevated-Cr group which had more diabetes, chronic obstructive pulmonary disease, and chronic and acute renal insufficiency. Both groups had similar open ATAAD repair procedures. Postoperative outcomes in the elevated-Cr group were significantly worse, including six times higher operative mortality (20% versus 3.4%, P < 0.0001). The landmark long-term survival after discharge alive was significantly worse in the elevated-Cr group than the normal-Cr group (10-y survival: 48% versus 69%, P = 0.0009). The elevated Cr on dialysis at discharge group had significantly worse five-year survival (40%) than the elevated Cr not on dialysis at discharge group (80%, P = 0.02) and the normal-Cr group (87%, P < 0.0001). Additionally, the elevated Cr not on dialysis had a worse five-year survival than the normal-Cr group (80% versus 87%, P = 0.02). Elevated Cr at discharge on dialysis was a significant risk factor for late mortality (hazard ratio = 4.22, 95% confidence interval: [2.07, 8.61], P < 0.0001). CONCLUSIONS: Renal dysfunction at discharge was associated with significantly decreased short-term and long-term survival following open ATAAD repair. Surgeons should aggressively prevent renal dysfunction, especially new-onset dialysis, at discharge as it is correlated with significantly worse short-term and long-term outcomes.

Knockout of the C3a receptor protects against renal ischemia reperfusion injury by reduction of NETs formation.

Renal ischemia/reperfusion (I/R) injury is a local sterile inflammatory response driven by innate immunity. Emerging data have revealed that complement and neutrophils contribute to hyperinflammation and oxidative stress in I/R induced acute kidney injury (AKI). However, the interplay between the C3a/C3aR axis and neutrophil extracellular traps (NETs) is imcompletelyunderstood. Here, we utilize genetically engineered mouse models and pharmacological inhibitors to investigate this association. The C3a/C3aR axis is found to promote neutrophil recruitment and NETs formation, thereby accelerating renal damage and dysfunction. Knockout of C3aR restores NETs release and improves renal function after I/R injury. Antibody-mediated blockade of NETs can also significantly ameliorate renal tubular injury and inflammation. Consistently, under stimulation by C3a, neutrophils are activated to promote NETs formation and subsequent renal tubular epithelial cell damage, and blocking C3aR rescued the injury. Interfering with reactive oxygen species (ROS) accumulation in neutrophils by antioxidant treatment significantly attenuates NETs formation. Our findings demonstrate that the C3a/C3aR-ROS-NETs axis constitutes a promising target for prevention or treatment of renal I/R injury.

BrABF3 promotes flowering through the direct activation of CONSTANS transcription in pak choi.

Drought stress triggers the accumulation of the phytohormone abscisic acid (ABA), which in turn activates the expression of the floral integrator gene CONSTANS (CO), accelerating flowering. However, the molecular mechanism of ABA-induced CO activation remains elusive. Here, we conducted a yeast one-hybrid assay using the CO promoter from Brassica campestris (syn. Brassica rapa) ssp. chinensis (pak choi) to screen the ABA-induced pak choi library and identified the transcription activator ABF3 (BrABF3). BrABF3, the expression of which was induced by ABA in pak choi, directly bound to the CO promoter from both pak choi and Arabidopsis. The BrABF3 promoter is specifically active in the Arabidopsis leaf vascular tissue, where CO is mainly expressed. Impaired BrABF3 expression in pak choi decreased BrCO expression levels and delayed flowering, whereas ectopic expression of BrABF3 in Arabidopsis increased CO expression and induced earlier flowering under the long-day conditions. Electrophoretic mobility shift assay analysis showed that BrABF3 was enriched at the canonical ABA-responsive element-ABRE binding factor (ABRE-ABF) binding motifs of the BrCO promoter. The direct binding of BrABF3 to the ABRE elements of CO was further confirmed by chromatin immunoprecipitation quantitative PCR. In addition, the induction of BrCO transcription by BrABF3 could be repressed by BrCDF1 in the morning. Thus, our results suggest that ABA could accelerate the floral transition by directly activating BrCO transcription through BrABF3 in pak choi.

PUS7 promotes the proliferation of colorectal cancer cells by directly stabilizing SIRT1 to activate the Wnt/ß-catenin pathway.

Pseudouridine synthase 7 (PUS7) may play key roles in cancer development. However, few studies have been conducted in this area. In the present study, we explored the function and potential mechanisms of PUS7 in colorectal cancer (CRC) progression. We found that PUS7 had higher expression in CRC tissues and cell lines. Clinically, high expression of PUS7 was associated with an unfavorable prognosis for CRC patients. Functionally, knockdown of PUS7 suppressed the proliferation of CRC cells in vitro and inhibited tumorigenicity in vivo. Mechanistically, RNA sequencing and coimmunoprecipitation (Co-IP) indicated that PUS7 exhibited oncogenic functions through the interaction of Sirtuin 1 (SIRT1) and activated the Wnt/ß-catenin signaling pathway. Thus, our findings suggest that PUS7 promotes the proliferation of CRC cells by directly stabilizing SIRT1 to activate the Wnt/ß-catenin pathway.

C3a/C3aR synergies with TGF-ß to promote epithelial-mesenchymal transition of renal tubular epithelial cells via the activation of the NLRP3 inflammasome.

BACKGROUND: Complement component 3a and its receptor (C3a/C3aR) and the nucleotide-binding oligomerization domain-like receptor protein-3 (NLRP3) inflammasome contribute to epithelial-mesenchymal transition (EMT). However, the relationship between C3a/C3aR and the NLRP3 inflammasome in EMT remains unclear. This study aimed to elucidate the roles of C3a/C3aR and the NLRP3 inflammasome involved in TGF-ß-induced EMT. METHOD: Mouse renal tubular epithelial cells (TCMK-1) were exposed to C3a and TGF-ß for 48 h. C3aR antagonist, MCC950, an inhibitor of the NLRP3 inflammasome and PD98059, an inhibitor of ERK signaling, were respectively applied to pretreat the cells at 30 min before C3a and TGF-ß administration.The cells were collected for western blot, immunofluorescence staining and ELISA. Unilateral ureteral obstruction (UUO) models were established using male C57BL/6 wild-type (WT) mice and age-matched C3aR-deficient mice. MCC950 was intraperitoneally injected in UUO mice. Kidney samples were collected for immunohistochemistry staining. RESULTS: In vitro, C3a synergized with TGF-ß to promote EMT and the activation of the NLRP3 inflammasome. Inhibition of C3aR attenuated EMT and the activation of the NLRP3 inflammasome. Inhibition of the NLRP3 inflammasome alleviated EMT but didn't affect the expression of C3aR. Inhibition of ERK signaling inhibited the activation of the NLRP3 inflammasome. In vivo, the expression of IL-1ß was significantly higher in UUO mice compared to the sham-operated mice. C3aR deficiency and inhibition of the NLRP3 Inflammasome contributed to decreased IL-1ß in UUO mice. CONCLUSION: Our data revealed that C3a/C3aR synergies with TGF-ß to activate the NLRP3 inflammasome to promote epithelial-mesenchymal transition of renal tubular epithelial cells through ERK signaling, and the way in which C3aR activates the inflammasome is to promote the assembly of the NLRP3 inflammasome.

540-degree deflecting lens and its general version.

We demonstrate an isotropic device called 540-degree deflecting lens, which has symmetric refractive index and can deflect parallel beam by 540 degrees. The expression of its gradient refractive index is obtained and generalized. We discover it's an optical absolute instrument with self-imaging characteristic. Using conformal mapping, we deduce its general version in one-dimensional space. We also introduce a combined lens called the generalized inside-out 540-degree deflecting lens similar to the inside-out Eaton lens. Ray tracing and wave simulations are used to demonstrate their characteristics. Our study expands the family of absolute instruments and provides new ideas to design optical systems.

Sp1 Controls the Basal Level of Interleukin-34 Transcription.

Interleukin-34 (IL-34) is a cytokine that plays important roles at steady state and in diseases. The induced or inhibited expression of IL-34 by stimuli has been deeply investigated. However, the regulation of IL-34 basal expression is largely unknown. The aim of this study is to investigate whether IL-34 expression is regulated by a general transcription factor Specificity Protein 1 (Sp1) at transcription level. By using bioinformatic software, four putative Sp1-binding sites overlapping GC boxes were found in the core promoter region of IL-34. Alignment of the core promoter sequences of mammalian IL-34 showed GC box-C (-62/-57) and D (-11/-6) were conserved in some mammals. Luciferase assay results showed that only deletion of GC box-C (-62/-57) significantly reduced luciferase activities of IL-34 core promoter in SH-SY5Y cells. By using electrophoretic mobility shift assay (EMSA), it was found that Sp1 specifically interacted with GC box-C sequence CCCGCC (-62/-57) in the core promoter of IL-34. By using chromatin immunoprecipitation (ChIP), it was discovered that Sp1 bound to the core promoter of IL-34 in living cells. In addition, silencing of Sp1 expression by its specific siRNA reduced IL-34 mRNA and protein levels significantly in SH-SY5Y cells. Likewise, IL-34 expression was inhibited in a dose-dependent manner by a Sp1 inhibitor Plicamycin. Furthermore, silencing of Sp1 also downregulated mRNA and protein expression of IL-34 in GES-1 and 293T cell lines, suggesting that IL-34 transcription regulated by Sp1 was not cell-type specific. Taken together, these results indicate that Sp1 controls the basal level of IL-34 transcription.

Removal of sulfonamide antibiotics by a sonocatalytic Fenton-like reaction: Efficiency and mechanisms.

With the widespread use of sulfonamide antibiotics (SAs), SAs are detected as residues in aquatic environments, posing a serious threat to human life and safety. Because of their high water solubility, fast transmission rate, and strong antibacterial properties, the safe disposal of SAs has become a key constraint for water quality assurance. Therefore, an ultrasound (US)-assisted zero-valent iron (ZVI)/persulfate (PS) system was proposed to explore the rapid and effective degradation of SAs. Comparative experiments were performed to study the removal of sulfadiazine (SDZ) by US, ZVI, PS, US/ZVI, US/PS, ZVI/PS, and US-ZVI/PS systems, respectively. Experimental results indicated that the highest removal efficiency of SDZ was ahieved in US-ZVI/PS system (97.4%), which were 2-44 times higher than that in other systems. Furthermore, the degradation efficiency of five typical SAs was achieved over 95%, demonstrating the effectiveness of the US ZVI/PS system for SAs removal. Also, quantum chemical computations for potential reactive sites of SAs and intermediate product detection by HPLC‒MS/MS were performed. The radical attack on active sites of SAs, such as N atom (number 7), was the main reason for SAs removal in US-ZVI/PS system. Besides, the common degradation pathways of six typical SAs were defined as S-N bond cleavage, C-N bond cleavage, benzene ring hydroxylation, aniline oxidation, and R substituent oxidation. Interestingly, the unique pathway of "SO2 group extraction" was observed in the degradation of six-membered ring SAs. Therefore, the US-ZVI/PS system is a promising and cost-effective method for the removal of SAs and other refractory pollutants.

ADAR2 increases in exercised heart and protects against myocardial infarction and doxorubicin-induced cardiotoxicity.

Exercise training benefits the heart. The knowledge of post-transcription regulation, especially RNA editing, in hearts remain rare. ADAR2 is an enzyme that edits adenosine to inosine nucleotides in double-stranded RNA, and RNA editing is associated with many human diseases. We found that ADAR2 was upregulated in hearts during exercise training. AAV9-mediated cardiac-specific ADAR2 overexpression attenuated acute myocardial infarction (AMI), MI remodeling, and doxorubicin (DOX)-induced cardiotoxicity. In vitro, overexpression of ADAR2 inhibited DOX-induced cardiomyocyte (CM) apoptosis. but it could also induce neonatal rat CM proliferation. Mechanistically, ADAR2 could regulate the abundance of mature miR-34a in CMs. Regulations of miR-34a or its target genes (Sirt1, Cyclin D1, and Bcl2) could affect the pro-proliferation and anti-apoptosis effects of ADAR2 on CMs. These data demonstrated that exercise-induced ADAR2 protects the heart from MI and DOX-induced cardiotoxicity. Our work suggests that ADAR2 overexpression or a post-transcriptional associated RNA editing via ADAR2 may be a promising therapeutic strategy for heart diseases.

FOSL1 promotes proneural-to-mesenchymal transition of glioblastoma stem cells via UBC9/CYLD/NF-κB axis.

Proneural (PN) to mesenchymal (MES) transition (PMT) is a crucial phenotypic shift in glioblastoma stem cells (GSCs). However, the mechanisms driving this process remain poorly understood. Here, we report that Fos-like antigen 1 (FOSL1), a component of AP1 transcription factor complexes, is a key player in regulating PMT. FOSL1 is predominantly expressed in the MES subtype, but not PN subtype, of GSCs. Knocking down FOSL1 expression in MES GSCs leads to the loss of MES features and tumor-initiating ability, whereas ectopic expression of FOSL1 in PN GSCs is able to induce PMT and maintain MES features. Moreover, FOSL1 facilitates ionizing radiation (IR)-induced PMT and radioresistance of PN GSCs. Inhibition of FOSL1 enhances the anti-tumor effects of IR by preventing IR-induced PMT. Mechanistically, we find that FOSL1 promotes UBC9-dependent CYLD SUMOylation, thereby inducing K63-linked polyubiquitination of major nuclear factor κB (NF-κB) intermediaries and subsequent NF-κB activation, which results in PMT induction in GSCs. Our study underscores the importance of FOSL1 in the regulation of PMT and suggests that therapeutic targeting of FOSL1 holds promise to attenuate molecular subtype switching in patients with glioblastomas.

Low Skeletal Muscle Mass and the Incidence of Delirium in Hospitalized Older Patients: A Systematic Review and Meta-Analysis of Observational Studies.

Background: Both low skeletal muscle mass and delirium are prevalent in older hospitalized patients, while their associations are unclear. This systematic review and meta-analysis aim to investigate the associations between low skeletal muscle mass and the incidence of delirium in hospitalized patients. Methods: The PubMed, Web of Science, and Embase were searched for relevant studies published before May 2022, and we conducted this systematic review and meta-analysis according to the PRISMA and MOOSE guidelines. The summary odds ratios (OR) and 95% confidence intervals (CI) were estimated, and subgroup analyses were also conducted according to the age and major surgeries. Results: Finally, nine studies with 3 828 patients were included. The pooled result showed no significant association between low skeletal muscle mass and the incidence of delirium (OR 1.69, 95% CI 0.85 to 2.52). However, sensitivity analysis suggested that one study caused a significant alteration of the summary result, and the meta-analysis of the remaining 8 studies showed that low skeletal muscle mass was significantly associated with an 88% increased incidence of delirium (OR 1.88, 95% CI 1.43 to 2.33). Furthermore, subgroup analyses indicated that low skeletal muscle mass was associated with a higher incidence of delirium in patients ≥75 years old or undergoing major surgeries instead of those <75 years old or without surgeries, respectively. Conclusions: Hospitalized patients with low skeletal muscle mass might have higher incidence of delirium, particularly in those of older age and undergoing major surgeries. Therefore, great attention should be paid to these patients.

Prevalence of mental disorders among middle school students in Shaoxing, China.

BACKGROUND: In China, adolescents account for about a quarter of those treated for mental disorders each year, and adolescent mental health issues have become a social hotspot. Although several epidemiological surveys of mental disorders have been conducted in China, no study has yet focused on the prevalence of mental disorders among adolescents in a certain region of Zhejiang. METHODS: In the first stage, 8219 middle school students aged 12-18 years in a city of Zhejiang Province (Shaoxing) were screened with the mental health screening checklist. In the second stage, participants who screened positive were tested with the Mini International Neuropsychiatric Interview for Children and Adolescents (MINI-KID) and the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV). Then, the prevalence of mental disorders were calculated. RESULTS: The overall prevalence in this population was 12.4%, with prevalence rates exceeding 20% in both the 17- and 18-year-old age groups. The most common mental disorders were obsessive-compulsive disorder (OCD) (9.1%) and major depressive disorder (MDD) (8.9%). CONCLUSIONS: Mental disorders are common among middle school students, and girls are at higher risk than boys. As the most prevalent mental disorders, OCD and MDD should receive timely attention, especially for upper grade students.

Facial Kinship Verification: A Comprehensive Review and Outlook.

The goal of Facial Kinship Verification (FKV) is to automatically determine whether two individuals have a kin relationship or not from their given facial images or videos. It is an emerging and challenging problem that has attracted increasing attention due to its practical applications. Over the past decade, significant progress has been achieved in this new field. Handcrafted features and deep learning techniques have been widely studied in FKV. The goal of this paper is to conduct a comprehensive review of the problem of FKV. We cover different aspects of the research, including problem definition, challenges, applications, benchmark datasets, a taxonomy of existing methods, and state-of-the-art performance. In retrospect of what has been achieved so far, we identify gaps in current research and discuss potential future research directions.

Progression of aortic root based on long-term imaging studies after acute type A dissection repair.

BACKGROUND: To determine the progression of aortic root in acute type A aortic dissection (ATAAD) patients after aortic root repair (ARr) or replacement (ARR) based on long-term follow-up imaging studies. METHODS: From 1996 to 2019, 732 patients had ATAAD repair at our institution. Six hundred and seven of these patients had either ARr, (n = 383) or ARR (n = 224). Eighty-one patients were excluded due to a lack of postoperative imaging. Three hundred and thirty-two patients were included in the repair group and 194 patients in the replacement group for long-term follow-up imaging study. RESULTS: Compared to the ARR group, the ARr group was significantly older (60 years vs. 55 years) and had more patients with hypertension (79% vs. 63%) but less male patients (63% vs. 79%) and connective tissue disorder (1.8% vs 8%). The ARr group had more zone two arch replacement (22% vs. 11%), similar HCA time (35 min vs. 31 min), shorter cardiopulmonary bypass time (203 min vs. 266 min), aortic cross-clamp time (128 min vs. 214 min), and fewer concomitant coronary artery bypass (3.9% vs. 8.9%). The root growth rate over 12 years was similar between the repair and replacement group (0.20 mm/year vs. 0.18 mm/year, p = .75). Both the repair and replacement group had similar 15-year cumulative incidence of reoperation (6.9% vs. 5.9%; p = .67), operative mortality (7.8% vs. 8.5%; p = .78), and 15-year survival (51% vs. 52%; p = .40). CONCLUSIONS: There was minimal growth of the aortic root after root repair or replacement for ATAAD patients. Both aortic root repair and replacement were acceptable techniques for ATAAD surgery in select patients.

Hypothermic circulatory arrest versus aortic clamping in thoracic and thoracoabdominal aortic aneurysm repair.

BACKGROUND: To compare perioperative and midterm outcomes in thoracic and thoraco-abdominal aortic aneurysm (TAA and TAAA) repair using hypothermic circulatory arrest (HCA) or aortic clamping (AC) with mild hypothermia. METHODS: From 2012 to 2021 there were 180 open repairs of a TAA or TAAA, of which 90 (50%) were done with HCA and 90 (50%) with aortic clamping with mild hypothermia. The indications for HCA were arch aneurysm, TAA from chronic aortic dissection, and inability to clamp the aorta for proximal anastomosis. RESULTS: Compared to AC, the HCA group had less prior descending aorta replacement/repair (9.1% vs. 32%, p = 0.0001). Intraoperatively, the HCA group had more TAAs (70% vs. 20%, p < 0.0001) while the AC group had more TAAAs (80% vs. 30%, p < 0.0001). HCA group had longer cardiopulmonary bypass times (242 vs. 181 min, p < 0.0001) but shorter cross-clamp time (39 vs. 120 min, p < 0.0001) and lower temperatures (18°C vs. 34°C, p < 0.0001). Postoperatively, the HCA group had longer intubation times (31 vs. 26 h, p = 0.002), but all other postoperative outcomes including paralysis (2.2% vs. 8.9%, p = 0.08), and operative mortality (4.4% vs. 2.2%, p = 0.68) were similar between HCA and AC groups. Patient age was an independent risk factor for postoperative paralysis (OR 1.07, p = 0.03) while HCA was not significant (OR 0.37, p = 0.21). Five-year survival was similar between HCA and AC groups (85% vs. 80%, p = 0.36). CONCLUSIONS: Postoperative outcomes and midterm survival were acceptable in thoracic and thoracoabdominal aneurysm patients after HCA or AC. Both HCA and AC with mild hypothermia were valid approaches in TAA/A repair.

Determining optimal donor heart ischemic times in adult cardiac transplantation.

OBJECTIVES: Unsupervised statistical determination of optimal allograft ischemic time (IT) on heart transplant outcomes among ABO donor heart types. METHODS: We identified 36,145 heart transplants (2000-2018) from the United Network for Organ Sharing database. Continuous and categorical variables were analyzed with parametric and nonparametric testing. Determination of IT cutoffs for survival analysis was performed using Contal and O'Quigley univariable method and Vito Muggeo multivariable segmented modeling. RESULTS: Univariable and multivariable IT threshold determination revealed a cutoff at about 3 h. The hourly increase in survival risk with ≥3 h IT is asymmetrically experienced at the early 90 days (hazard ratio [HR] = 1.29, p < .001) and up to 1-year time point (HR = 1.16, p < .001). Beyond 1 year the risk of prolonged IT is less impactful (HR = 1.04, p = .022). Longer IT was associated with more postoperative complications such as stroke (2.7% vs. 2.3, p = .042), dialysis (11.6% vs. 9.1%, p < .001) and death from primary graft dysfunction (1.8% vs. 1.2%, p < .001). O blood type donor hearts with IT ≥ 3 h has significantly increased hourly mortality risk at 90 days (HR = 1.27, p < .001), 90 days to 1 year (HR = 1.22, p < .001) and >1 year (HR = 1.05, p = .041). For non-O blood types with ≥3 h IT hourly mortality risk was increased at 90 days (HR = 1.33, p < .001), but not at 90 days to 1 year (HR = 1.09, p = .146) nor ≥1 year (HR = 1.08, p = .237). CONCLUSIONS: The donor heart IT threshold for survival determined from unbiased statistical modeling occurs at 3 h. With longer preservation times, transplantation with O donor hearts was associated with worse survival.