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Recently, environmental temperature has been shown to regulate bone homeostasis. However, the mechanisms by which cold exposure affects bone mass remain unclear. In our present study, we observed that exposure to cold temperature (CT) decreased bone mass and quality in mice. Furthermore, a transplant of exosomes derived from the plasma of mice exposed to cold temperature (CT-EXO) can also impair the osteogenic differentiation of BMSCs and decrease bone mass by inhibiting autophagic activity. Rapamycin, a potent inducer of autophagy, can reverse cold exposure or CT-EXO-induced bone loss. Microarray sequencing revealed that cold exposure increases the miR-25-3p level in CT-EXO. Mechanistic studies showed that miR-25-3p can inhibit the osteogenic differentiation and autophagic activity of BMSCs. It is shown that inhibition of exosomes release or downregulation of miR-25-3p level can suppress CT-induced bone loss. This study identifies that CT-EXO mediates CT-induced osteoporotic effects through miR-25-3p by inhibiting autophagy via targeting SATB2, presenting a novel mechanism underlying the effect of cold temperature on bone mass.
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Autofagia , Temperatura Baixa , Exossomos , Camundongos Endogâmicos C57BL , MicroRNAs , Osteogênese , Animais , Autofagia/efeitos dos fármacos , Camundongos , Exossomos/metabolismo , MicroRNAs/metabolismo , MicroRNAs/genética , Osteogênese/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Osteoporose/patologia , Diferenciação Celular/efeitos dos fármacos , Osso e Ossos/metabolismo , Feminino , Densidade Óssea , Sirolimo/farmacologiaRESUMO
BACKGROUND: International experience shows that the suitability of a high-performance healthcare system for its given purposes is reflected in its ability to provide a continuum of services that match the changing health status of the given population. Although many low- and middle-income countries have sought to bring movement away from hospital-centered and towards patient-centered healthcare, such efforts have often had poor results, and one of the major reasons for this is the inability to accurately identify which inpatients need continuing care and what kind of continuing of care is needed. OBJECTIVES: To measure and assess the continuing care needs of discharged patients and its influencing factors in rural China. METHODS: Data were obtained from the hospital database of Medical Center M in County Z from May to July 2022. County Z is a county of 1 million people in central China. The database includes basic patient information, disease-related information, and information on readiness for hospital discharge. Factors related to the need for continuing care were included in the analysis. The Readiness for Hospital Discharge Scale was used to assess the need for continuing care. The statistical data are expressed in terms of both frequency and composition ratio. Finally, linear regression was used to analyze the factors influencing the need for continuing care. RESULTS: The analysis included a total of 3,791 patients, 123 of whom (3.25%) had continuing nursing needs. The need of continuing nursing was related to patients' age group, mode of admission, occupation and major diagnostic categories (P < 0.05). CONCLUSIONS: Developing continuing care is an important initiative for bridging the fragmentation of health services, and an appropriate supply system for continuing care, interconnected with inpatient services, should be established in rural areas in China as soon as possible. And provide more appropriate care for patients in need.
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Hospitalização , Pacientes Internados , Humanos , Atenção à Saúde , Alta do Paciente , ChinaRESUMO
Objective: This study investigates the efficacy of tangerine peel lemon glycerin extract oral spray in improving oral mucosal barrier, reducing microinflammation, and addressing malnutrition in maintenance dialysis (MHD) patients. Methods: Tangerine peel and dry lemon underwent glycerin extraction. From January 2021 to June 2022, 72 MHD patients with thirst were prospectively chosen at Sinopharm Gezhouba Central Hospital. Randomization divided them into an observation group (n=36) and a control group (n=36). Both received routine maintenance dialysis and chronic kidney disease management. Oral conditions were assessed using OHIP-14, a homemade visual thirst score scale, SFR, sAA, and saliva pH. Microinflammatory indexes (CRP, TNF-α, IL-6) and nutritional status indicators (Alb, PA, Hb) were measured. The observation group used 1ml of tangerine peel lemon glycerin extract with a pH value of 5.9~6.1 q6h, while the control group used 1ml of purified water q6h. Results: After 3 months, the observation group showed significant improvement in OHIP-14 and visual thirst score scale (P < .01). Saliva pH, CRP, TNF-α, and IL-6 levels decreased, and SAA activity, SFR, Alb, PA, and Hb levels increased significantly in the observation group compared to the control group (P < .01). Conclusions: Tangerine peel lemon glycerin spray demonstrates promise in improving the oral mucosal barrier, exhibiting antibacterial and anti-inflammatory properties that mitigate microinflammation and malnutrition. This finding suggests a connection between oral health, systemic pathology, psychological state, and social adaptability.
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In this contribution, we report a computational study of the vibrational Resonance Raman (vRR) spectra of cytosine in water, on the grounds of potential energy surfaces (PES) computed by time-dependent density functional theory (TD-DFT) and CAM-B3LYP and PBE0 functionals. Cytosine is interesting because it is characterized by several close-lying and coupled electronic states, challenging the approach commonly used to compute the vRR for systems where the excitation frequency is in quasi-resonance with a single state. We adopt two recently developed time-dependent approaches, based either on quantum dynamical numerical propagations of vibronic wavepackets on coupled PES or on analytical correlation functions for cases in which inter-state couplings were neglected. In this way, we compute the vRR spectra, considering the quasi-resonance with the eight lowest-energy excited states, disentangling the role of their inter-state couplings from the mere interference of their different contributions to the transition polarizability. We show that these effects are only moderate in the excitation energy range explored by experiments, where the spectral patterns can be rationalized from the simple analysis of displacements of the equilibrium positions along the different states. Conversely, at higher energies, interference and inter-state couplings play a major role, and the adoption of a fully non-adiabatic approach is strongly recommended. We also investigate the effect of specific solute-solvent interactions on the vRR spectra, by considering a cluster of cytosine, hydrogen-bonded by six water molecules, and embedded in a polarizable continuum. We show that their inclusion remarkably improves the agreement with the experiments, mainly altering the composition of the normal modes, in terms of internal valence coordinates. We also document cases, mostly for low-frequency modes, in which a cluster model is not sufficient, and more elaborate mixed quantum classical approaches, in explicit solvent models, need to be applied.
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We present a viable protocol to compute vibrational resonance Raman (vRR) spectra for systems with several close-lying and potentially coupled electronic states. It is based on the parametrization of linear vibronic coupling (LVC) models from time-dependent density functional theory (TD-DFT) calculations and quantum dynamics propagations of vibronic wavepackets with the multilayer version of the multiconfiguration time-dependent Hartree (ML-MCTDH) method. Our approach is applied to thymine considering seven coupled electronic states, comprising the three lowest bright states, and all vibrational coordinates. Computed vRR at different excitation wavelengths are in good agreement with the available experimental data. Up to 250 nm the signal is dominated by the lowest HOMO â LUMO transition, whereas at 233 nm, in the valley between the two lowest energy absorption bands, the contributions of all the three bright states, and their interferences and couplings, are important. Inclusion of solvent (water) effects improves the agreement with experiment, reproducing the coalescence of vibrational bands due to CC and CâO stretchings. With our approach we disentangle and assess the effect of interferences between the contribution of different quasi-resonant states to the transition polarizability and the effect of interstate couplings. Our findings strongly suggest that in cases of close-lying and potentially coupled states a simple inclusion of interference effects is not sufficient, and a fully nonadiabatic computation should instead be performed. We also document that for systems with strong couplings and quasi-degenerate states, the use of HT perturbative approach, not designed for these cases, may lead to large artifacts.
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Teoria Quântica , Timina , Vibração , Solventes , ÁguaRESUMO
The pathogenesis of vascular calcification in diabetic patients remains elusive. As an effective information transmitter, small extracellular vesicles (sEVs) carry abundant microRNAs (miRNAs) that regulate the physiological and pathological states of recipient cells. In the present study, significant up-regulation of miR-126-5p was observed in sEVs isolated from human umbilical vein endothelial cells (HUVECs) stimulated with advanced glycation end-products (A-EC/sEVs). Intriguingly, these sEVs suppressed the osteogenic differentiation of vascular smooth muscle cells (VSMCs) by targeting BMPR1B, which encodes the receptor for BMP, thereby blocking the smad1/5/9 signalling pathway. In addition, knocking down miR-126-5p in HUVECs significantly diminished the anti-calcification effect of A-EC/sEVs in a mouse model of type 2 diabetes. Overall, miR-126-5p is highly enriched in sEVs derived from AGEs stimulated HUVECs and can target BMPR1B to negatively regulate the trans-differentiation of VSMCs both in vitro and in vivo.
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Diabetes Mellitus Tipo 2 , Vesículas Extracelulares , MicroRNAs , Calcificação Vascular , Animais , Vesículas Extracelulares/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Camundongos , MicroRNAs/metabolismo , Osteogênese , Calcificação Vascular/metabolismo , Calcificação Vascular/patologiaRESUMO
BACKGROUND: To investigate new lncRNAs as molecular markers of T2D. METHODS: We used microarrays to identify differentially expressed lncRNAs and mRNAs from five patients with T2D and paired controls. Through bioinformatics analysis, qRT-PCR validation, ELISA, and receiver operating characteristic (ROC) curve analysis of 100 patients with T2D and 100 controls to evaluate the correlation between lncRNAs and T2D, and whether lncRNAs could be used in the diagnosis of T2D patients. RESULTS: We identified 68 and 74 differentially expressed lncRNAs and mRNAs, respectively. The top five upregulated lncRNAs are ENST00000381108.3, ENST00000515544.1, ENST00000539543.1, ENST00000508174.1, and ENST00000564527.1, and the top five downregulated lncRNAs are TCONS_00017539, ENST00000430816.1, ENST00000533203.1, ENST00000609522.1, and ENST00000417079.1. The top five upregulated mRNAs are Q59H50, CYP27A1, DNASE1L3, GRIP2, and lnc-TMEM18-12, and the top five downregulated mRNAs are GSTM4, PODN, GLYATL2, ZNF772, and CLTC. Examination of lncRNA-mRNA interaction pairs indicated that the target gene of lncRNA XR_108954.2 is E2F2. Multiple linear regression analysis showed that XR_108954.2 (r = 0.387, p < 0.01) and E2F2 (r = 0.368, p < 0.01) expression levels were positively correlated with glucose metabolism indicators. Moreover, E2F2 was positively correlated with lipid metabolism indicators (r = 0.333, p < 0.05). The area under the ROC curve was 0.704 (95% CI: 0.578-0.830, p = 0.05) for lncRNA XR_108954.2 and 0.653 (95% CI: 0.516-0.790, p = 0.035) for E2F2. CONCLUSIONS: This transcriptome analysis explored the aberrantly expressed lncRNAs and identified E2F2 and lncRNA XR_108954.2 as potential biomarkers for patients with T2D.
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Diabetes Mellitus Tipo 2 , RNA Longo não Codificante , Biomarcadores , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/genética , Perfilação da Expressão Gênica , Humanos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA Mensageiro/genéticaRESUMO
Based on the newly developed SCAN meta-GGA and the widely used PBE-GGA functionals, ab initio molecular dynamics are performed on water. It is proved that, although the SCAN meta-GGA is not as good as the TIP4P/2005 model potential in describing the equation of state of water, it is much better than the PBE-GGA, the ST2 model potential, and ab initio trained neural network potentials. Moreover, the SCAN meta-GGA predicts a first-order liquid-liquid transition from high- to low-density water at negative pressure, in which the structures are qualitatively consistent with experimental observations, and the spinodal point of high-density water is very close to Speedy's stability limit line.
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The anharmonic force fields and spectroscopic constants of the electronic ground state (XÌ1A') for the HAsO molecule are reported employing the MP2, B3LYP, B3P86, and B3PW91 methods with cc-pVQZ and cc-pV5Z basis sets. The calculated molecular geometries, rotational constants, vibrational frequencies, and anharmonic constants of the HAsO molecule are compared with the experimental data. It is found that the best agreement between the calculated results and experiment data is at the B3LYP/cc-pV5Z theoretical level. The predicted cubic and quartic force fields, vibration-rotation interaction constants, quartic and sextic centrifugal distortion constants, and Coriolis coupling constants of the HAsO molecule at the B3LYP/cc-pV5Z theoretical level are expected to be reliable.
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Lysobacter harbors a plethora of cryptic biosynthetic gene clusters (BGCs), albeit only a limited number have been analyzed to date. In this study, we described the activation of a cryptic polyketide synthase (PKS)/nonribosomal peptide synthetase (NRPS) gene cluster (lsh) in Lysobacter sp. DSM 3655 through promoter engineering and heterologous expression in Streptomyces sp. S001. As a result of this methodology, we were able to isolate two novel linear lipopeptides, lysohexaenetides A (1) and B (2), from the recombinant strain S001-lsh. Furthermore, we proposed the biosynthetic pathway for lysohexaenetides and identified LshA as another example of entirely iterative bacterial PKSs. This study highlights the potential of heterologous expression systems in uncovering cryptic biosynthetic pathways in Lysobacter genomes, particularly in the absence of genetic manipulation tools.
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Lysobacter , Streptomyces , Lysobacter/genética , Lysobacter/metabolismo , Streptomyces/genética , Streptomyces/metabolismo , Lipopeptídeos/genética , Lipopeptídeos/metabolismo , Policetídeo Sintases/genética , Família MultigênicaRESUMO
Introduction: Necroptosis is an alternative, caspase-independent programmed cell death that appears when apoptosis is inhibited. A gowing number of studies have reflected the link between necroptosis and tumors. However, only some systematical bibliometric analyses were focused on this field. In this study, we aimed to identify and visualize the cooperation between countries, institutions, authors, and journals through a bibliometric analysis to help understand the hotspot trends and emerging topics regarding necroptosis and cancer research. Methods: The articles and reviews on necroptosis and cancer were obtained from the Web of Science Core Collection on 16 September 2022. Countries, institutions, authors, references, and keywords in this field were visually analyzed by CtieSpace 5.8.R3, VOSviewer 1.6.18, and R package "bibliometrix." Results: From 2006 to 2022, 2,216 qualified original articles and reviews on necroptosis in tumors were published in 685 academic journals by 13,009 authors in 789 institutions from 75 countries/regions. Publications focusing on necroptosis and cancer have increased violently in the past 16 years, while the citation number peaked around 2008-2011. Most publications were from China, while the United States maintained the dominant position as a "knowledge bridge" in necroptosis and cancer research; meanwhile, Ghent University and the Chinese Academy of Sciences were the most productive institutions. Moreover, only a tiny portion of the articles were multiple-country publications. Peter Vandenabeele had the most significant publications, while Alexei Degterev was most often co-cited. Peter Vandenabeele also gets the highest h-index and g-index in this research field. Cell Death and Disease was the journal with the most publications on necroptosis and cancer, which was confirmed to be the top core source by Bradford's Law. At the same time, Cell was the leading co-cited journal, and the focus area of these papers was molecular, biology, and immunology. High-frequency keywords mainly contained those that are molecularly related (MLKL, NF-kB, TNF, RIPK3, RIPK1), pathological process related (necroptosis, apoptosis, cell-death, necrosis, autophagy), and mechanism related (activation, expression, mechanisms, and inhibition). Conclusion: This study comprehensively overviews necroptosis and cancer research using bibliometric and visual methods. Research related to necroptosis and cancer is flourishing. Cooperation and communication between countries and institutions must be further strengthened. The information in our paper would provide valuable references for scholars focusing on necroptosis and cancer.
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Head and neck squamous cell carcinoma (HNSCC) is a highly prevalent and heterogeneous malignancy with a dismal overall survival rate. Nevertheless, the effective biomarkers remain ambiguous and merit further investigation. Cuproptosis is a novel defined pathway of programmed cell death that contributes to the progression of cancers. Meanwhile, long non-coding RNAs (lncRNAs) play a crucial role in the biological process of tumors. Nevertheless, the prognostic value of cuproptosis-related lncRNAs in HNSCC is still obscure. This study aimed to develop a new cuproptosis-related lncRNAs (CRLs) signature to estimate survival and tumor immunity in patients with HNSCC. Herein, 620 cuproptosis-related lncRNAs were identified from The Cancer Genome Atlas database through the co-expression method. To construct a risk model and validate the accuracy of the results, the samples were divided into two cohorts randomly and equally. Subsequently, a prognostic model based on five CRLs was constructed by the Cox regression analysis with the least absolute shrinkage and selection operator (LASSO) algorithm. In addition, the prognostic potential of the five-CRL signature was verified via Cox regression, survival analysis, the receiver operating characteristic (ROC) curve, nomogram, and clinicopathologic characteristics correlation analysis. Furthermore, we explored the associations between the signature risk score (RS) and immune landscape, somatic gene mutation, and drug sensitivity. Finally, we gathered six clinical samples and different HNSCC cell lines to validate our bioinformatics results. Overall, the proposed novel five-CRL signature can predict prognosis and assess the efficacy of immunotherapy and targeted therapies to prolong the survival of patients with HNSCC.
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The structural diversity of polycyclic tetramate macrolactams (PoTeMs) are mainly generated by the cyclases and cytochrome P450s (CYPs). The PoTeM cluster sah in Saccharopolyspora hirsuta harboring two CYP genes was combinatorially reassembled and heterologously expressed in Streptomyces. As a result, six new cytotoxic PoTeMs, sahamides A-F (1-6), were discovered, and 1-3 are the first examples of oxidized one-ring PoTeMs. Remarkably, SahE represents the first CYP performing oxidative modification on the ornithine moiety of PoTeMs.
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Streptomyces , Sistema Enzimático do Citocromo P-450/metabolismo , Ornitina/metabolismo , Oxirredução , Streptomyces/químicaRESUMO
Fungal pathogens are common causes of superficial clinical infection. Their increasing drug resistance gradually makes existing antifungal drugs ineffective. Heat stable antifungal factor (HSAF) is a novel antifungal natural product with a unique structure. However, the application of HSAF has been hampered by very low yield in the current microbial producers and from extremely poor solubility in water and common solvents. In this study, we developed an effective mode of treatment applying HSAF to superficial fungal infections. The marine-derived Lysobacter enzymogenes YC36 contains the HSAF biosynthetic gene cluster, which we activated by the interspecific signaling molecule indole. An efficient extraction strategy was used to significantly improve the purity to 95.3%. Scanning electron microscopy images revealed that the Type I collagen-based HSAF (Col-HSAF) has a transparent appearance and good physical properties, and the in vitro sustained-release effect of HSAF was maintained for more than 2 weeks. The effective therapeutic concentration of Col-HSAF against superficial fungal infection was explored, and Col-HSAF showed good biocompatibility, lower clinical scores, mild histological changes, and antifungal capabilities in animals with Aspergillus fumigatus keratitis and cutaneous candidiasis. In conclusion, Col-HSAF is an antifungal reagent with significant clinical value in the treatment of superficial fungal infections.
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Arterial medial calcification is a common disease in patients with type 2 diabetes, end-stage renal disease and hypertension, resulting in high incidence and mortality of cardiovascular event. H19 has been demonstrated to be involved in cardiovascular diseases like aortic valve diseases. However, role of H19 in arterial medial calcification remains largely unknown. We identified that H19 was upregulated in ß-glycerophosphate (ß-GP) induced vascular smooth muscle cells (VSMCs), a cellular calcification model in vitro. Overexpression of H19 potentiated while knockdown of H19 inhibited osteogenic differentiation of VSMCs, as demonstrated by changes of osteogenic genes Runx2 and ALP as well as ALP activity. Notably, H19 interacted with miR-140-5p directly, as demonstrated by luciferase report system and RIP analysis. Mechanistically, miR-140-5p attenuated osteoblastic differentiation of VSMCs by targeting Satb2 and overexpression of miR-140-5p blocked H19 induced elevation of Satb2 as well as the promotion of osteoblastic differentiation of VSMCs. Interestingly, over-expression of Satb2 induced phosphorylation of ERK1/2 and p38MAPK. In conclusion, H19 promotes VSMC calcification by acting as competing endogenous RNA of miR-140-5p and at least partially by activating Satb2-induced ERK1/2 and p38MAPK signaling.
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Arterial calcification is highly prevalent, particularly in patients with end-stage renal disease (ESRD). The osteogenic differentiation of vascular smooth muscle cells (VSMCs) is the critical process for the development of arterial calcification. However, the detailed mechanism of VSMCs calcification remains to be elucidated. Here, we investigated the role of exosomes (Exos) derived from endothelial cells (ECs) in arterial calcification and its potential mechanisms in ESRD. Accelerated VSMCs calcification was observed when VSMCs were exposed to ECs culture media stimulated by uremic serum or high concentration of inorganic phosphate (3.5 mM Pi). and the pro-calcification effect of the ECs culture media was attenuated by exosome depletion. Exosomes derived from high concentrations of inorganic phosphate-induced ECs (ECsHPi-Exos) could be uptaken by VSMCs and promoted VSMCs calcification. Microarray analysis showed that miR-670-3p was dramatically increased in ECsHPi-Exos compared with exosomes derived from normal concentrations of inorganic phosphate (0.9 mM Pi) induced ECs (ECsNPi-Exos). Mechanistically, insulin-like growth factor 1 (IGF-1) was identified as the downstream target of miR-670-3p in regulating VSMCs calcification. Notably, ECs-specific knock-in of miR-670-3p of the 5/6 nephrectomy with a high-phosphate diet (miR-670-3pEC-KI + NTP) mice that upregulated the level of miR-670-3p in artery tissues and significantly increased artery calcification. Finally, we validated that the level of circulation of plasma exosomal miR-670-3p was much higher in patients with ESRD compared with healthy controls. Elevated levels of plasma exosomal miR-670-3p were associated with a decline in IGF-1 and more severe artery calcification in patients with ESRD. Collectively, these findings suggested that ECs-derived exosomal miR-670-3p could promote arterial calcification by targeting IGF-1, which may serve as a potential therapeutic target for arterial calcification in ESRD patients.
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Exossomos , Falência Renal Crônica , MicroRNAs , Calcificação Vascular , Animais , Meios de Cultura/farmacologia , Células Endoteliais/metabolismo , Exossomos/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Falência Renal Crônica/metabolismo , Camundongos , MicroRNAs/metabolismo , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Osteogênese , Fosfatos/metabolismo , Fósforo/metabolismo , Fósforo/farmacologia , Calcificação Vascular/metabolismoRESUMO
Histone methylation is an epigenetic change mediated by histone methyltransferase, and has been connected to the beginning and progression of several diseases. The most common ailments that affect the elderly are cardiovascular and cerebrovascular disorders. They are the leading causes of death, and their incidence is linked to vascular calcification (VC). The key mechanism of VC is the transformation of vascular smooth muscle cells (VSMCs) into osteoblast-like phenotypes, which is a highly adjustable process involving a variety of complex pathophysiological processes, such as metabolic abnormalities, apoptosis, oxidative stress and signalling pathways. Many researchers have investigated the mechanism of VC and related targets for the prevention and treatment of cardiovascular and cerebrovascular diseases. Their findings revealed that histone lysine methylation modification may play a key role in the various stages of VC. As a result, a thorough examination of the role and mechanism of lysine methylation modification in physiological and pathological states is critical, not only for identifying specific molecular markers of VC and new therapeutic targets, but also for directing the development of new related drugs. Finally, we provide this review to discover the association between histone methylation modification and VC, as well as diverse approaches with which to investigate the pathophysiology of VC and prospective treatment possibilities.
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Lisina , Calcificação Vascular , Idoso , Histonas/metabolismo , Humanos , Metilação , Estudos Prospectivos , Calcificação Vascular/genética , Calcificação Vascular/patologiaRESUMO
Vascular calcification is prevalent in aging, diabetes, chronic kidney disease, cardiovascular disease, and certain genetic disorders. However, the pathogenesis of vascular calcification is not well-understood. It has been progressively recognized that vascular calcification depends on the bidirectional interactions between vascular cells and their microenvironment. Exosomes are an essential bridge to mediate crosstalk between cells and organisms, and thus they have attracted increased research attention in recent years. Accumulating evidence has indicated that exosomes play an important role in cardiovascular disease, especially in vascular calcification. In this review, we introduce vascular biology and focus on the crosstalk between the different vessel layers and how their interplay controls the process of vascular calcification.
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We compute the line shapes of absorption (ABS), emission (EMI), electronic circular dichroism (ECD), and circularly polarized luminescence (CPL) of a fluorene-fused [7]helicene. To elucidate different physico-chemical factors responsible for the spectral shapes, we account for Franck-Condon (FC) contribution, Herzberg-Teller (HT) effect and Duschinsky rotation, as well as the solvent inhomogenous broadening. The latter is connected to the solvent reorganization energy which is calculated with the state-specific (SS) implementation of Polarizable Continuum Model (PCM). To understand the relative importance of different effects of equilibrium geometry displacements, frequencies changes, and Duschinsky mixing, we carefully compare and discuss the results of Adiabatic Hessian (AH), Adiabatic Shift and Frequencies (ASF), and Adiabatic Shift (AS) models in details. Our results agree with the experimental spectra very well. They show that FC contribution dominates the spectral shapes and HT effect leads to the break of mirror images between absorptive (ABS + ECD) and emissive (EMI + CPL) spectra.
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This work presents a systematic investigation of the spectroscopic properties at anharmonic force fields of ground electronic state ([Formula: see text]) of LiNH2, which are calculated using second-order Møller-Plesset perturbation theory (MP2) and density functional theory (DFT) with hybrid GGA and meta-hybrid GGA (M06-2X) exchange-correlation functional. Two high angular momentum basis sets of 6-311+g (2d, p) and 6-311++g (3df, 2pd) are used. The equilibrium geometries, ground-state rotational constants, harmonic frequencies, and quartic and sextic centrifugal distortion constants of LiNH2 are calculated and compared with corresponding experimental or theoretical data. The predicted accuracy of the calculated constants has been confirmed by analyzing the deviations with respect to experiment. In addition, the anharmonic constants, vibration-rotation interaction constants, force constants, and Coriolis coupling constants of LiNH2 are firstly obtained. The infrared spectrum is predicted and together with the first prediction on the higher-order anharmonic constants contributes to a better understanding of the vibrational and rotational characteristics of LiNH2, thus revealing its internal structure. Graphical abstract The IR spectra and the magnified IR spectra at 3500 cm-1 in harmonic approximations of LiNH2 using B3P86, M06-2X and MP2 methods combining with 6-311++g(3df,2pd).