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1.
Quant Imaging Med Surg ; 14(5): 3731-3743, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38720861

RESUMEN

Background: Post-hepatectomy liver failure (PHLF) is still a predominant cause of hepatectomy-related mortality. However, it is difficult to evaluate the remnant liver functional reserve accurately before surgery to prevent PHLF. In this study, we aimed to explore the role of gadoxetate disodium-enhanced magnetic resonance imaging (MRI) in evaluating remnant liver functional reserve. Methods: For this cross-sectional study, the sample retrospectively included 56 patients undergoing liver resections of at least three segments between June 2019 and September 2022 at The General Hospital of the Western Theater Command. Pre-surgery assessments involved liver computer tomography (CT), an indocyanine green (ICG) clearance test, the Child-Pugh scoring system, and liver function serum biochemical indicators. Each patient underwent a gadoxetate disodium-enhanced MRI before the hepatectomy, and we measured the remnant hepatocellular uptake index (rHUI) as well as the standard remnant hepatocellular uptake index (SrHUI). We examined the diagnostic utility of rHUI, SrHUI, indocyanine green retention rate of 15 minutes (ICG R15), and Albumin for PHLF. Receiver operating characteristics (ROC) analyses were used to measure the preoperative liver function parameters (namely, rHUI, SrHUI, ICG R15, and Albumin) for predicting PHLF. The areas under the curve (AUCs) were calculated and compared between different preoperative liver function parameters using the Wilson/Brown method. The Pearson or Spearman correlation coefficient was used for correlation analysis between ICG R15, Albumin, and rHUI and between ICG R15, Albumin, and SrHUI, respectively. Results: Twelve patients (21.43%) had complications of PHLF. We found significant differences in rHUI, SrHUI, ICG R15, and Albumin between the non-PHLF and PHLF groups. The pooled r between ICG R15 and rHUI was -0.591 [95% confidence interval (CI): -0.740 to -0.389, P<0.001], and between ICG R15 and SrHUI was -0.534 (95% CI: -0.703 to -0.308, P<0.001). The area under the curve (AUC) values of rHUI, SrHUI, ICG R15, and Ablumin were 0.871 (sensitivity 81.82%; specificity 91.67%), 0.878 (sensitivity 79.55%; specificity 83.33%), 0.835 (sensitivity 99.73%; specificity 66.67%), and 0.782 (sensitivity 88.64%; specificity 58.33%), respectively. Conclusions: We found that the rHUI and SrHUI calculated using the gadoxetate disodium-enhanced MRI reflected a combination of remnant hepatocyte function and liver volume, and these were useful as a quantitative assessment indicator of remnant liver functional reserve and can be a better predictor of PHLF after major hepatic resection.

2.
ISME J ; 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38747389

RESUMEN

Spillovers of viruses into human occur more frequently under warmer conditions, particularly arboviruses. The invasive tick species Haemaphysalis longicornis poses a significant public health threat due to its global expansion and its potential to carry a wide range of pathogens. We analyzed meta-transcriptomic data from 3595 adult H. longicornis ticks collected between 2016 and 2019 in 22 provinces across China, encompassing diverse ecological conditions. Generalized additive modelling revealed that climate factors exerted a stronger influence on the virome of H. longicornis compared to other ecological factors, such as ecotypes, distance to coastline, animal host, tick gender, and anti-viral immunity. We investigated the mechanistic understanding of how climate changes drive the tick virome using causality inference and emphasized its significance for public health. Our findings demonstrated that higher temperatures and lower relative humidity/precipitation contribute to variations in animal host diversity, leading to an increased diversity of tick virome, particularly the evenness of vertebrate associated viruses. This finding may explain the evolution of tick-borne viruses into generalists across multiple hosts, thereby increasing the probability of spillover events involving tick-borne pathogens. Deep learning projections indicate that the diversity of H. longicornis virome is expected to increase in 81.9% of regions under the SSP8.5 scenario from 2019-2030. Extension of surveillance should be implemented to avert the spread of tick-borne diseases.

3.
Materials (Basel) ; 17(9)2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38730822

RESUMEN

Thermal deformation behavior of Cu-Cr-Sn alloy ingots under deformation temperatures ranging from 600 °C to 950 °C and strain rates from 0.01 s-1 to 10 s-1 was investigated in detail. The thermal deformation constitutive equation and thermal processing map of the alloy were established, respectively. The activation energy Q was determined as 430.61 KJ/mol. The optimal deformation system corresponding to the hot working diagram was a deformation temperature of 900 °C and strain rate of 0.1 s-1. Under these deformation conditions, twin dynamic recrystallization (TDRX), continuous dynamic recrystallization (CDRX), and discontinuous dynamic recrystallization (DDRX) occurred simultaneously, with the twinning process causing the stress-strain curve to exhibit a wavy change. The thermal deformation microstructure of the alloy is co-regulated by different recrystallization mechanisms, with DDRX occurring mainly at low deformation temperatures, and both CDRX and DDRX occurring at high deformation temperatures.

5.
Bioorg Med Chem ; 107: 117760, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38762978

RESUMEN

Oncolytic peptides represented potential novel candidates for anticancer treatments especially drug-resistant cancer cell lines. One of the most promising and extensively studied is LTX-315, which is considered as the first in class oncolytic peptide and has entered phase I/II clinical trials. Nevertheless, the shortcomings including poor proteolytic stability, moderate anticancer durability and high synthesis costs may hinder the widespread clinical applications of LTX-315. In order to reduce the synthesis costs, as well as develop derivatives possessing both high protease-stability and durable anticancer efficiency, twenty LTX-315-based derived-peptides were designed and efficiently synthesized. Especially, through solid-phase S-alkylation, as well as the optimized peptide cleavage condition, the derived peptides could be prepared with drastically reduced synthesis cost. The in vitro anticancer efficiency, serum stability, anticancer durability, anti-migration activity, and hemolysis effect were systematically investigated. It was found that derived peptide MS-13 exhibited comparable anticancer efficiency and durability to those of LTX-315. Strikingly, the D-type peptide MS-20, which is the enantiomer of MS-13, was demonstrated to possess significantly high proteolytic stability and sustained anticancer durability. In general, the cost-effective synthesis and stability-guided structural optimizations were conducted on LTX-315, affording the highly hydrolysis resistant MS-20 which possessed durable anticancer activity. Meanwhile, this study also provided a reliable reference for the future optimization of anticancer peptides through the solid-phase S-alkylation and L-type to D-type amino acid substitutions.

6.
J Chem Phys ; 160(18)2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38738611

RESUMEN

We perform detailed potential energy surface explorations of BeM(CO)3- (M = Co, Rh, Ir) and BeM(CO)3 (M = Ni, Pd, Pt) using both single-reference and multireference-based methods. The present results at the CASPT2(12,12)/def2-QZVPD//M06-D3/def2-TZVPPD level reveal that the global minimum of BeM(CO)3- (M = Co, Rh, Ir) and BePt(CO)3 is a C3v symmetric structure with an 1A1 electronic state, where Be is located in a terminal position bonded to M along the center axis. For other cases, the C3v symmetric structure is a low-lying local minimum. Although the present complexes are isoelectronic with the recently reported BFe(CO)3- complex having a B-Fe quadruple bond, radial orbital-energy slope (ROS) analysis reveals that the highest occupied molecular orbital (HOMO) in the title complexes is slightly antibonding in nature, which bars a quadruple bonding assignment. Similar weak antibonding nature of HOMO in the previously reported BeM(CO)4 (M = Ru, Os) complexes is also noted in ROS analysis. The bonding analysis through energy decomposition analysis in combination with the natural orbital for chemical valence shows that the bonding between Be and M(CO)3q (q = -1 for M = Co, Rh, Ir and q = 0 for M = Ni, Pd, Pt) can be best described as Be in the ground state (1S) interacting with M(CO)30/- via dative bonds. The Be(spσ) → M(CO)3q σ-donation and the complementary Be(spσ) ← M(CO)3q σ-back donation make the overall σ bond, which is accompanied by two weak Be(pπ) ← M(CO)3q π-bonds. These complexes represent triply bonded terminal beryllium in an unusual zero oxidation state.

7.
Org Lett ; 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38738813

RESUMEN

Herein, we present a decarboxylative nucleophilic fluorination of carboxylic acids with a silver catalyst. This strategy enables the synthesis of a myriad of diverse and valuable fluorinated motifs under mild conditions, demonstrating good functional-group tolerance and utility in late-stage functionalization. In contrast to traditional electrophilic fluorination, this nucleophilic method utilizes a more readily available nucleophilic fluorinating reagent, providing substantial advantages in terms of cost efficiency, broad substrate scope, and functional-group compatibility.

8.
J Mater Chem B ; 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38775254

RESUMEN

Pancreatic cancer is an aggressive and highly fatal malignant tumor. Recent studies have shown that cancer stem cells (CSCs) play an important role in resisting current therapeutic modalities. Furthermore, CD133 is highly expressed in CSCs. High-intensity focused ultrasound (HIFU) is a promising non-invasive therapeutic strategy for unresectable pancreatic cancers. In our study, we synthesized targeted CD133 organosilane nanomicelles by encapsulating perfluorohexane (PFH). The CD133 antibody on the surface could specifically bind to CD133-positive pancreatic cancer cells and selectively concentrate in pancreatic cancer tumor tissues. PFH was introduced to improve the ablation effect of HIFU due to its liquid-gas phase transition properties. By combining with the dorsal skinfold window chamber model (DSWC) of pancreatic cancer in nude mice, multiphoton fluorescence microscopy was used to evaluate the targeting effect of nanomicelles on pancreatic cancer tumor tissue. These multifunctional nanomicelles synergistically affected HIFU treatment of pancreatic cancer, providing an integrated research platform for diagnosing and treating pancreatic cancer with HIFU.

9.
Nat Commun ; 15(1): 4105, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38750023

RESUMEN

Molybdenum and its alloys are known for their superior strength among body-centered cubic materials. However, their widespread application is hindered by a significant decrease in ductility at lower temperatures. In this study, we demonstrate the achievement of exceptional ductility in a Mo alloy containing rare-earth La2O3 nanoparticles through rotary-swaging, a rarity in Mo-based materials. Our analysis reveals that the large ductility originates from substantial variations in the electronic density of states, a characteristic intrinsic to rare-earth elements. This characteristic can accelerate the generation of oxygen vacancies, facilitating the amorphization of the oxide-matrix interface. This process promotes vacancy absorption and modification of dislocation configurations. Furthermore, by inducing irregular shapes in the La2O3 nanoparticles through rotary-swaging, incoming dislocations interact with them, creating multiple dislocation sources near the interface. These dislocation sources act as potent initiators at even reduced temperatures, fostering diverse dislocation types and intricate networks, ultimately enhancing dislocation plasticity.

10.
Sci Adv ; 10(18): eadk1698, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38701206

RESUMEN

Deltas are threatened by erosion due to climate change and reduced sediment supply, but their response to these changes remains poorly quantified. We investigate the abandoned Yellow River delta that has transitioned from rapid growth to ongoing deterioration due to a river avulsion removing the sediment supply. Integrating bathymetric data, process observations, and sediment transport modeling, we find that while the subaerial delta was stabilized by engineering measures, the subaqueous delta continued to erode due to intensified storms, losing 39% of its mass deposited before the avulsion. Long-term observations show that winter storms initiate scouring of the subaqueous delta, contributing up to 70% of seabed erosion. We then analyze 108 global deltas to assess subaqueous delta erosion risks and identify 17 deltas facing similar situations of sediment decline and storm intensification during the past 40 years. Our findings suggest that subaqueous delta erosion must be integrated into delta sustainability evaluations.

11.
Biomed Pharmacother ; 175: 116682, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38703507

RESUMEN

The interaction between endoplasmic reticulum (ER) and mitochondria has been shown to play a key role in hepatic steatosis during chronic obesity. ß-nicotinamide mononucleotide (NMN) has been reported to regulate obesity, however, its molecular mechanism at the subcellular level remains unclear. Here, NMN improved liver steatosis and insulin resistance in chronic high-fat diet (HFD) mice. RNA-seq showed that compared with the liver of HFD mice, NMN intervention enhanced fat digestion and absorption and stimulated the cholesterol metabolism signaling pathways, while impaired insulin resistance and the fatty acid biosynthesis signaling pathways. Mechanistically, NMN ameliorated mitochondrial dysfunction and ER oxidative stress in the liver of HFD mice by increasing hepatic nicotinamide adenine dinucleotide (NAD+) (P < 0.01) levels. This effect increased the contact sites (mitochondria-associated membranes [MAMs]) between ER and mitochondria, thereby promoting intracellular ATP (P < 0.05) production and mitigating lipid metabolic disturbances in the liver of HFD mice. Taken together, this study provided a theoretical basis for restoring metabolic dynamic equilibrium in the liver of HFD mice by increasing MAMs via the nutritional strategy of NMN supplementation.

12.
Indian J Hematol Blood Transfus ; 40(2): 289-296, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38708160

RESUMEN

Reliable indicators that can predict drug responsiveness in primary immune thrombocytopenia (ITP) patients are urgent. We aimed to establish a reference interval of percentage of immature platelet fraction (IPF%) and absolute immature platelet count (A-IPC), and assess their efficacy in discriminating ITP patients from controls, especially their predictive value for responsiveness to drug treatment. We retrospectively studied 72 treatment-naive adult patients with ITP who received Dexamethasone monotherapy or combination therapy. Baseline (pretreatment) information was collected from medical records. Reference intervals for A-IPC and IPF% were established based on controls and their effectiveness in discriminating ITP patients from controls was assessed. Predictive value of pretreatment IPF% and A-IPC at four co-primary endpoints of treatment response in patients were investigated. The 95% reference intervals for A-IPC and IPF% were (2.7-15.6) × 109/L and 1.2%-7.3%, respectively. Both A-IPC and IPF% had excellent discrimination ability for ITP patients from controls. It showed highly statistically significant differences in pretreatment A-IPC for predicting treatment response at day 7 between responders and non-responders, but not at days 14, 21 and 28. Pretreatment A-IPC had the higher area under the ROC curve with a cut-off of 0.86 than that of IPF% with a cut-off of 14.5% in predicting the treatment response in ITP patients at day 7. Pretreatment A-IPC exhibited acceptable predictive power and could be a promising predictor of response to short-term Dexamethasone monotherapy or combination therapy at day 7 in ITP patients.

13.
Int J Biol Macromol ; : 132408, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38754683

RESUMEN

Porcine Epidemic Diarrhea Virus (PEDV) is a highly contagious virus that causes Porcine Epidemic Diarrhea (PED). This enteric disease results in high mortality rates in piglets, leading to significant financial losses in the pig industry. However, vaccines cannot provide sufficient protection against epidemic strains. Spike (S) protein exposed on the surface of virion mediates PEDV entry into cells. Our findings imply that matrine (MT), a naturally occurring alkaloid, inhibits PEDV infection targeting S protein of virions and biological process of cells. The GLY434 residue in the autodocking site of the S protein and MT conserved based on sequence comparison. This study provides a comprehensive analysis of viral attachment, entry, and virucidal effects to investigate how that MT inhibits virus replication. MT inhibits PEDV attachment and entry by targeting S protein. MT was added to cells before, during, or after infection, it exhibits anti-PEDV activities and viricidal effects. Network pharmacology focuses on addressing causal mechanisms rather than just treating symptoms. We identified the key genes and screened the cell apoptosis involved in the inhibition of MT on PEDV infection in network pharmacology. MT significantly promotes cell apoptosis in PEDV-infected cells to inhibit PEDV infection by activating the MAPK signaling pathway. Collectively, we provide the biological foundations for the development of single components of traditional Chinese medicine to inhibit PEDV infection and spread.

14.
Trends Mol Med ; 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38719712

RESUMEN

While the dopaminergic system is important for cognitive processes, it is also sensitive to the influence of physical activity (PA). We summarize current evidence on whether PA-related changes in the human dopaminergic system are associated with alterations in cognitive performance, discuss recent advances, and highlight challenges and opportunities for future research.

15.
Nanomaterials (Basel) ; 14(9)2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38727391

RESUMEN

Nanomaterials, with unique physical, chemical, and biocompatible properties, have attracted significant attention as an emerging active platform in cancer diagnosis and treatment. Amongst them, metal-organic framework (MOF) nanostructures are particularly promising as a nanomedicine due to their exceptional surface functionalities, adsorption properties, and organo-inorganic hybrid characteristics. Furthermore, when bioactive substances are integrated into the structure of MOFs, these materials can be used as anti-tumor agents with superior performance compared to traditional nanomaterials. In this review, we highlight the most recent advances in MOFs-based materials for tumor therapy, including their application in cancer treatment and the underlying mechanisms.

16.
Eur Radiol ; 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38750169

RESUMEN

OBJECTIVES: To evaluate signal enhancement ratio (SER) for tissue characterization and prognosis stratification in pancreatic adenocarcinoma (PDAC), with quantitative histopathological analysis (QHA) as the reference standard. METHODS: This retrospective study included 277 PDAC patients who underwent multi-phase contrast-enhanced (CE) MRI and whole-slide imaging (WSI) from three centers (2015-2021). SER is defined as (SIlt - SIpre)/(SIea - SIpre), where SIpre, SIea, and SIlt represent the signal intensity of the tumor in pre-contrast, early-, and late post-contrast images, respectively. Deep-learning algorithms were implemented to quantify the stroma, epithelium, and lumen of PDAC on WSIs. Correlation, regression, and Bland-Altman analyses were utilized to investigate the associations between SER and QHA. The prognostic significance of SER on overall survival (OS) was evaluated using Cox regression analysis and Kaplan-Meier curves. RESULTS: The internal dataset comprised 159 patients, which was further divided into training, validation, and internal test datasets (n = 60, 41, and 58, respectively). Sixty-five and 53 patients were included in two external test datasets. Excluding lumen, SER demonstrated significant correlations with stroma (r = 0.29-0.74, all p < 0.001) and epithelium (r = -0.23 to -0.71, all p < 0.001) across a wide post-injection time window (range, 25-300 s). Bland-Altman analysis revealed a small bias between SER and QHA for quantifying stroma/epithelium in individual training, validation (all within ± 2%), and three test datasets (all within ± 4%). Moreover, SER-predicted low stromal proportion was independently associated with worse OS (HR = 1.84 (1.17-2.91), p = 0.009) in training and validation datasets, which remained significant across three combined test datasets (HR = 1.73 (1.25-2.41), p = 0.001). CONCLUSION: SER of multi-phase CE-MRI allows for tissue characterization and prognosis stratification in PDAC. CLINICAL RELEVANCE STATEMENT: The signal enhancement ratio of multi-phase CE-MRI can serve as a novel imaging biomarker for characterizing tissue composition and holds the potential for improving patient stratification and therapy in PDAC. KEY POINTS: Imaging biomarkers are needed to better characterize tumor tissue in pancreatic adenocarcinoma. Signal enhancement ratio (SER)-predicted stromal/epithelial proportion showed good agreement with histopathology measurements across three distinct centers. Signal enhancement ratio (SER)-predicted stromal proportion was demonstrated to be an independent prognostic factor for OS in PDAC.

17.
Artículo en Inglés | MEDLINE | ID: mdl-38565964

RESUMEN

Graft failure is a fatal complication following allogeneic stem cell transplantation where a second transplantation is usually required for salvage. However, there are no recommended regimens for second transplantations for graft failure, especially in the haploidentical transplant setting. We recently reported encouraging outcomes using a novel method (haploidentical transplantation from a different donor after conditioning with fludarabine and cyclophosphamide). Herein, we report updated outcomes in 30 patients using this method. The median time of the second transplantation was 96.5 (33-215) days after the first transplantation. Except for one patient who died at +19d and before engraftment, neutrophil engraftments were achieved in all patients at 11 (8-24) days, while platelet engraftments were achieved in 22 (75.8%) patients at 17.5 (9-140) days. The 1-year OS and DFS were 60% and 53.3%, and CIR and TRM was 6.7% and 33.3%, respectively. Compared with the historical group, neutrophil engraftment (100% versus 58.5%, p < 0.001) and platelet engraftment (75.8% versus 32.3%, p < 0.001) were better in the novel regimen group, and OS was also improved (60.0% versus 26.4%, p = 0.011). In conclusion, salvage haploidentical transplantation from a different donor using the novel regimen represents a promising option to rescue patients with graft failure after the first haploidentical transplantation.

18.
Open Med (Wars) ; 19(1): 20240926, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38584830

RESUMEN

Ex vivo liver resection combined with autologous liver transplantation offers the opportunity to treat otherwise unresectable hepatobiliary malignancies and has been applied in clinic. The implementation of enhanced recovery after surgery (ERAS) program improves the outcome of surgical procedures. This is a retrospective single-center study including 11 cases of patients with liver cancer that underwent autologous liver transplantation and received ERAS: cholangiocarcinoma of the hilar region (n = 5), intrahepatic cholangiocarcinoma (n = 3), gallbladder cancer (n = 1), liver metastasis from colorectal cancer (n = 1), and liver metastasis from gastrointestinal mesenchymal tumor (n = 1). There were no deaths within 30 days and major complications occurred in two patients, and four patients were readmitted upon the first month after the surgery. Median hospital stay was 20 days (range 13-44) and median open diet was Day 4 (range 2-9) after surgery and median early post-operative activity was Day 5 (range 2-9) after surgery. In conclusion, autologous liver transplantation is feasible in the treatment of otherwise unresectable hepatobiliary malignancies, and our study showed favorable results with autologous liver transplantation in ERAS modality. ERAS modality provides a good option for some patients whose tumors cannot be resected in situ and offers a chance for rapid recovery.

19.
Br J Radiol ; 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38588565

RESUMEN

PURPOSE: To conduct a meta-analysis to assess the efficacy of intravascular ultrasound (IVUS) during transjugular intrahepatic portosystemic shunt (TIPS) creation. METHODS: MEDLINE and Embase databases were queried until July 2022 for comparative studies reporting procedure metrics for TIPS creation with or without IVUS guidance. Meta-analysis was performed with random-effects modeling for total procedural time, time to portal venous access, fluoroscopy time, iodinated contrast volume use, air kerma, dose area product, and number of needle passes. Intraoperative procedure-related complications were also reviewed. RESULTS: Of 95 unique records initially identified, 6 were eligible for inclusion. A total of 194 and 240 patients underwent TIPS with and without IVUS guidance. Pooled analyses indicated that IVUS guidance was associated with reduced total procedure time (SMD -0.76 [95% CI -1.02, -0.50] P < 0.001), time to portal venous access (SMD -0.41 [95% CI -0.67, -0.15] P = 0.002), fluoroscopy time (SMD, -0.54 [95% CI -1.02, -0.07]; P = 0.002), contrast volume use (SMD, -0.89 [95% CI -1.16, -0.63]; P < 0.001), air kerma (SMD, -0.75 [95% CI -1.11, -0.38]; P < 0.001) and dose area product (SMD, -0.98 [95% CI -1.77, -0.20]; P = 0.013). 4.2 and 7.8 needle passes were required in the IVUS and non-IVUS group, respectively (SMD, -0.60 [95% CI -1.42, 0.21]; P = 0.134), whereas pooled complication rates were 15.2% (12/79), and 21.4% (28/131), respectively. CONCLUSION: IVUS guidance during TIPS creation improves procedural metrics including procedural time, contrast usage, and radiation exposure.

20.
Chemistry ; : e202400714, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38622057

RESUMEN

Quantum chemical calculations using ab initio methods at the MRCI+Q(8,9)/def2-QZVPPD and CCSD(T)/def2-QZVPPD levels as well as density functional theory are reported for the diatomic molecules AeN- (Ae = Ca, Sr, Ba). The nature of the bonds is analyzed with a variety of methods. The anions CaN- and SrN- have electronic triplet (3Π) ground states with nearly identical bond dissociation energies De ~57 kcal/mol calculated at the MRCI+Q(8,9)/def2-QZVPPD level of theory. In contrast, the heavier homologue BaN- has a singlet (1Σ+) ground state, which is only 1.1 kcal/mol below the triplet (3Σ-) state. The computed bond dissociation energy of (1Σ+) BaN- is 68.4 kcal/mol. The calculations at the CCSD(T)-full/def2-QZVPPD and BP86-D3(BJ)/def2-QZVPPD levels of theory are in reasonable agreement with the MRCI+Q(8,9)/def2-QZVPPD data except for the singlet (1Σ+) state, which has a large multireference character. The calculated atomic partial charges given by the CM5, Voronoi and Hirshfeld methods suggest small to medium-sized charge donation toward Ae atom Ae←N- for most electronic states. In contrast, the NBO method predicts for all species medium to large electronic charge donation toward nitrogen Ae→N-, which is due to the neglect of the (n)p AOs of Ae atoms as genuine valence orbitals.

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