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Twisted bilayer graphene (tBLG) with C vacancies would greatly improve the density of states (DOS) around the Fermi level (EF) and quantum capacitance; however, the single-band tight-binding model only considering pz orbitals cannot accurately capture the low-energy physics of tBLG with C vacancies. In this work, a three-band tight-binding model containing three p orbitals of C atoms is proposed to explore the modulation mechanism of C vacancies on the DOS and quantum capacitance of tBLG. We first obtain the hopping integral parameters of the three-band tight-binding model, and then explore the electronic structures and the quantum capacitance of tBLG at a twisting angle of θ = 1.47° under different C vacancy concentrations. The impurity states contributed by C atoms with dangling bonds located around the EF and the interlayer hopping interaction could induce band splitting of the impurity states. Therefore, compared with the quantum capacitance of pristine tBLG (â¼18.82 µF cm-2) at zero bias, the quantum capacitance is improved to â¼172.76 µF cm-2 at zero bias, and the working window with relatively large quantum capacitance in the low-voltage range is broadened in tBLG with C vacancies due to the enhanced DOS around the EF. Moreover, the quantum capacitance of tBLG is further increased at zero bias with an increase of the C vacancy concentration induced by more impurity states. These findings not only provide a suitable multi-band tight-binding model to describe tBLG with C vacancies but also offer theoretical insight for designing electrode candidates for low-power consumption devices with improved quantum capacitance.
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Calcific aortic valve disease (CAVD) is a common valve disease characterized by the fibro-calcific remodeling of the aortic valves, which is an actively regulated process involving osteogenic differentiation of valvular interstitial cells (VICs). MicroRNA (miRNA) is an essential regulator in diverse biological processes in cells. The present study aimed to explore the role and mechanism of miR-22 in the osteogenic differentiation of VICs. The expression profile of osteogenesis-related miRNAs was first detected in aortic valve tissue from CAVD patients (n = 33) and healthy controls (n = 12). miR-22 was highly expressed in calcified valve tissues (P < 0.01), and the expression was positively correlated with the expression of OPN (rs = 0.820, P < 0.01) and Runx2 (rs = 0.563, P < 0.01) in VICs isolated from mild or moderately calcified valves. The sustained high expression of miR-22 was also validated in an in-vitro VICs osteogenic model. Adenovirus-mediated gain-of-function and loss-of-function experiments were then performed. Overexpression of miR-22 significantly accelerated the calcification process of VICs, manifested by significant increases in calcium deposition, alkaline phosphate activity, and expression of osteoblastic differentiation markers. Conversely, inhibition of miR-22 significantly negated the calcification process. Subsequently, calcium-binding protein 39 (CAB39) was identified as a target of miR-22. Overexpression of miR-22 significantly reduced the expression of CAB39 in VICs, leading to decreased catalytic activity of the CAB39-LKB1-STRAD complex, which, in turn, exacerbated changes in the AMPK-mTOR signaling pathway, and ultimately accelerated the calcification process. In addition, ROS generation and autophagic activity during VIC calcification were also regulated by miR-22/CAB39 pathway. These results indicate that miR-22 is an important accelerator of the osteogenic differentiation of VICs, and a potential therapeutic target in CAVD.
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Estenose da Valva Aórtica/patologia , Valva Aórtica/patologia , Calcinose/patologia , Proteínas de Ligação ao Cálcio/metabolismo , Diferenciação Celular , MicroRNAs/genética , Osteogênese , Idoso , Valva Aórtica/metabolismo , Estenose da Valva Aórtica/genética , Estenose da Valva Aórtica/metabolismo , Calcinose/genética , Calcinose/metabolismo , Proteínas de Ligação ao Cálcio/genética , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Spin-crossover combined with metal-insulator transition and superconductivity has been found in 2D transition-metal phosphorous trichalcogenides when tuning them by high pressure. Simulation of such intriguing spin-crossover behaviors is crucial to understanding the mechanism. The Hubbard U correction is widely used to describe the strong on-site Coulomb interaction in the d electrons of transition-metal compounds, while the U values are sensitive to the crystal field and spin state varying greatly with pressure. In this work, we show that taking MnPS3 as an example and based on a uniform parameter set, the hybrid functional calculations give a spin-crossover pressure of 35 GPa consistent with experimental observation (30 GPa), which is less than half of the existing reported value (63 GPa) using the Hubbard U correction. Notably, we find a spin-crossover induced transition from an antiferromagnetic semiconductor with monoclinic stacking-order to a ferromagnetic semiconductor with rhombohedral stacking-order, and the ferromagnetism originates from the partially occupied t2g orbitals. Different from previous understanding, the Mott metal-insulator transition of MnPS3 does not occur simultaneously with the spin-crossover but in a pressurized low-spin phase.
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Magnetism in the two-dimensional limit has become an intriguing topic for exploring new physical phenomena and potential applications. Especially, the two-dimensional magnetism is often associated with novel intrinsic spin fluctuations and versatile electronic structures, which provides vast opportunities in 2D material research. However, it is still challenging to verify candidate materials hosting two-dimensional magnetism, since the prototype systems have to be realized by using mechanical exfoliation or atomic layer deposition. Here, an alternative manipulation of two-dimensional magnetic properties via electrochemical intercalation of organic molecules is reported. Using tetrabutyl ammonium (TBA+), we synthesized a (TBA)Cr2Ge2Te6 hybrid superlattice with metallic behavior, and the Curie temperature is significantly increased from 67 K in pristine Cr2Ge2Te6 to 208 K in (TBA)Cr2Ge2Te6. Moreover, the magnetic easy axis changes from the ⟨001⟩ direction in Cr2Ge2Te6 to the ab-plane in (TBA)Cr2Ge2Te6. Theoretical calculations indicate that the drastic increase of the Curie temperature can be attributed to the change of magnetic coupling from a weak superexchange interaction in pristine Cr2Ge2Te6 to a strong double-exchange interaction in (TBA)Cr2Ge2Te6. These findings are the first demonstration of manipulation of magnetism in magnetic van der Waals materials by means of intercalating organic ions, which can serve as a convenient and efficient approach to explore versatile magnetic and electronic properties in van der Waals crystals.
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Exercise preconditioning (EP) attenuates pathological cardiac hypertrophy by increasing the functional capacity of the cardiovascular system; however, the underlying molecular mechanisms remain unclear. MicroRNAs (miRNAs) play important roles in various physiological and pathological processes by regulating the expression of the targeted gene. In this study, we aimed to screen the miRNAs involved in EP-attenuating pathological cardiac hypertrophy. The histological and echocardiographic parameters assessment showed that pathological cardiac hypertrophy induced by transverse aortic constriction (TAC) was significantly alleviated in EP treated rats. The left ventricular tissues (n = 3) from Sham, TAC and EP + TAC groups were subjected to small RNA deep sequencing. A total of 570 known mature miRNAs and 530 putative novel miRNAs were detected. DEGseq analysis showed that there were 37 and 88 differentially expressed miRNAs in the comparisons of TAC versus Sham and EP + TAC versus TAC, respectively. Among them, EP treatment could relieve the expression changes of 32 miRNAs, which were supposed to be involved in EP-attenuating pathological cardiac hypertrophy. After miRNAs target genes prediction by miRDB algorithm, pathway analysis showed that the most frequently represented pathways were involved in Calcium signaling pathway and MAPK signaling pathway. The results would provide valuable clues to finding therapeutic targets for the treatment of pathological cardiac hypertrophy.
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Cardiomegalia/patologia , Ventrículos do Coração/patologia , MicroRNAs/genética , Condicionamento Físico Animal/efeitos adversos , Animais , Sinalização do Cálcio/fisiologia , Cardiomegalia/diagnóstico por imagem , Cardiomegalia/metabolismo , Cardiomegalia/prevenção & controle , Ecocardiografia/métodos , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Masculino , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Condicionamento Físico Animal/fisiologia , Ratos , Ratos Sprague-Dawley/genética , Transdução de Sinais/fisiologiaRESUMO
Pathological cardiac hypertrophy, often accompanied by hypertension, aortic stenosis and valvular defects, is typically associated with myocyte remodeling and cardiac dysfunction. Exercise preconditioning (EP) has been proven to enhance the tolerance of the myocardium to cardiac ischemia-reperfusion injury. However, the effects of EP in pathological cardiac hypertrophy are rarely reported. 10-wk-old male Sprague-Dawley rats (n = 80) were randomly divided into four groups: sham, TAC, EP + sham and EP + TAC. Two EP groups were subjected to 4 weeks of treadmill training, and the EP + TAC and TAC groups were followed by TAC operations. The sham and EP + sham groups underwent the same operation without aortic constriction. Eight weeks after the surgery, we evaluated the effects of EP by echocardiography, morphology, and histology and observed the expressions of the associated proteins. Compared with the respective control groups, hypertrophy-related indicators were significantly increased in the TAC and EP + TAC groups (p < 0.05). However, between the TAC and EP + TAC groups, all of these changes were effectively inhibited by EP treatment (p < 0.05). Furthermore, EP treatment upregulated the expression of HSF1 and HSP70, increased the HSF1 levels in the nuclear fraction, inhibited the expression of the NF-κB p65 subunit, decreased the NF-κB p65 subunit levels in the nuclear fraction, and reduced the IL2 levels in the myocardia of rats. EP could effectively reduce the cardiac hypertrophic responses induced by TAC and may play a protective role by upregulating the expressions of HSF1 and HSP70, activating HSF1 and then inhibiting the expression of NF-κB p65 and nuclear translocation.
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Cardiomegalia/metabolismo , Proteínas de Ligação a DNA/fisiologia , Condicionamento Físico Animal , Fator de Transcrição RelA/fisiologia , Fatores de Transcrição/fisiologia , Animais , Sequência de Bases , Cardiomegalia/fisiopatologia , Primers do DNA , Fatores de Transcrição de Choque Térmico , Masculino , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo RealRESUMO
OBJECTIVE: To observe the effect of exercise preconditioning (EP) on pressure overload-induced pathological cardiac hypertrophy and explore related mechanisms. METHODS: Ten-week-old male Sprague-Dawley rats (n = 80) were randomly divided into four groups via random number table method: sham, TAC, EP + sham and EP + TAC. Two EP groups were subjected to 4 weeks of treadmill training, and followed by sham and TAC operations. Eight weeks after the surgery, mean arterial pressure (MAP), cardiac morphology, mRNA expressions of the B-type natriuretic peptide (BNP) and heat shock protein (HSP) 70 and protein expression of the BNP, heat shock transcription factor 1 (HSF1), HSP70, nuclear factor κB (NF-κB) p65, and interleukin-2 (IL-2) were examined. RESULTS: (1) Pathological cardiac hypertrophy index: eight weeks after TAC, MAP, heart size, HW/BW, cross-sectional area of the cardiomyocytes (CSA) and mRNA and protein expressions of BNP in the LV were all significantly higher in the TAC and EP + TAC groups than respective sham groups (all P < 0.05). HW/BW, CSA, and mRNA and protein expressions of BNP in the LV were significantly lower in EP + TAC group than in TAC group (all P < 0.05). (2) mRNA and protein expressions of HSF1 and HSP70 and nuclear HSF1 levels were significantly downregulated post TAC, however, EP treatment significantly increased the expression of HSF1 and nuclear HSF1 levels in TAC rats (all P < 0.05). (3) mRNA and protein expressions of NF-κB p65 and IL-2 were significantly increased in the TAC and EP + TAC groups compared with the respective sham groups (all P < 0.05), which were significantly downregulated in EP + TAC group compared to TAC group (all P < 0.05). CONCLUSIONS: EP could effectively reduce the cardiac hypertrophic responses induced by TAC possibly through upregulating the expressions of HSF1 and HSP70 and inhibiting the expression of NF-κB p65 and its nuclear translocation.
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Cardiomegalia , Transdução de Sinais , Animais , Proteínas de Ligação a DNA , Regulação para Baixo , Proteínas de Choque Térmico HSP70 , Fatores de Transcrição de Choque Térmico , Interleucina-2 , Masculino , Miócitos Cardíacos , Peptídeo Natriurético Encefálico , Condicionamento Físico Animal , RNA Mensageiro , Ratos , Ratos Sprague-Dawley , Fator de Transcrição RelA , Fatores de TranscriçãoRESUMO
BACKGROUND AND AIM OF THE STUDY: Intra-aortic balloon pump (IABP) in heart valve surgical patients is associated with a higher mortality than coronary artery bypass grafting (CABG). The study aim was to analyze the early outcome of heart valve surgical patients requiring IABP support, and to assess the risk factors for early mortality. METHODS: Among a cohort of 5,786 patients undergoing heart valve replacement without CABG, 81 (1.4%) required IABP support. Data from these latter patients were collected and analyzed retrospectively, and univariate and multivariate logistic regression were applied to identify risk factors for early mortality in patients requiring IABP support. RESULTS: IABP was inserted in 30 patients intraoperatively, and in 51 patients postoperatively. The overall mortality was 50.6%. Mortality in the intraoperative IABP subgroup was significantly lower than in the postoperative IABP subgroup (26.7% versus 64.7%, p = 0.001). The independent risk factors for early mortality were: age increasing by 10 years (OR 1.906, 95% CI: 1.165-3.116, p = 0.010) and pulmonary hypertension (OR 4.153, 95% CI: 1.380-12.499, p = 0.011). Intraoperative IABP insertion (OR 0.297, 95% CI: 0.100-0.876, p = 0.028) was identified as a protective factor compared to postoperative insertion. CONCLUSION: The mortality of patients requiring IABP support after heart valve replacement was high. The efficacy of intraoperative IABP insertion was better than a postoperative mandatory use. Clearly, more attention should be paid to older patients or those with pulmonary hypertension, who may benefit less from IABP.
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Implante de Prótese de Valva Cardíaca , Valvas Cardíacas/cirurgia , Balão Intra-Aórtico , Adulto , Fatores Etários , Feminino , Implante de Prótese de Valva Cardíaca/mortalidade , Humanos , Hipertensão Pulmonar/complicações , Período Intraoperatório , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Estudos Retrospectivos , Fatores de Risco , Resultado do TratamentoRESUMO
In this paper, we have systematically studied the electronic instability of pressured black phosphorous (BP) under strong magnetic field. We first present an effective model Hamiltonian for pressured BP near theLifshitzpoint. Then we show that when the magnetic field exceeds a critical value, the nodal-line semimetal (NLSM) state of BP with a small band overlap re-enters the semiconductive phase by re-opening a small gap. This results in a narrow-bandgap semiconductor with a partially flat valence band edge. Moreover, we demonstrate that above this critical magnetic field, two possible instabilities, i.e. charge density wave phase and excitonic insulator (EI) phase, are predicted as the ground state for high and low doping concentrations, respectively. By comparing our results with the experiment (Sunet al2018Sci. Bull.631539), we suggest that the field-induced instability observed experimentally corresponds to an EI. Furthermore, we propose that the semimetallic BP under pressure with small band overlaps may provide a good platform to study the magneto-exciton insulators. Our findings bring the first insight into the electronic instability of topological NLSM in the quantum limit.
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A variety of distinct anisotropic exchange interactions commonly exist in one magnetic material due to complex crystal, magnetic and orbital symmetries. Here we investigate the effects of multiple anisotropic exchange interactions on topological magnon in a honeycomb ferromagnet, and find a chirality-selective topological magnon phase transition induced by a complicated interplay of Dzyaloshinsky-Moriya interaction and pseudo-dipolar interaction, accompanied by the bulk gap close and reopen with chiral inversion. Moreover, this novel topological phase transition involves band inversion at high symmetry pointsKandK', which can be regarded as a pseudo-orbital reversal, i.e. magnon valley degree of freedom, implying a new manipulation corresponding to a sign change of the magnon thermal Hall conductivity. Indeed, it can be realized in 4dor 5dcorrelated materials with both spin-orbit coupling and orbital localized states, such as iridates and ruthenates,etc.This novel regulation may have potential applications on magnon devices and topological magnonics.
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Kagome lattice provides a distinctive platform to investigate various correlated electron orders. Recently, an unconventional charge density wave (CDW) with novel chirality is observed in the kagome metalAV3Sb5(A= K, Rb, Cs), and the origin of which is still unclear. Here, using a tight-binding model and the mean-field method, we calculate the electron order in the quasi-two-dimensional kagome lattice with 1/3 electron filling, and show that the chiral CDW emerges under a set of parameters withC6rotational symmetry but without mirror symmetry. Physically, the reason why we choose this set of parameters is based on the possible tangential distortion of the kagome lattice. Our results provide a fresh insight to understand the microscopic origin of the unconventional CDW inAV3Sb5.
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The Mn-Bi-Te family displaying magnetism and non-trivial topological properties has received extensive attention. Here, we predict that the antiferromagnetic structure of Mn3Bi2Te6with three MnTe layers is energetically stable and the magnetic energy difference of Mn-Mn is enhanced four times compared with that in the single MnTe layer of MnBi2Te4. The predicted Néel transition point is raised to 102.5 K, surpassing the temperature of liquid nitrogen. The topological properties show that with the variation of the MnTe layer from a single layer to three layers, the system transforms from a non-trivial topological phase to a trivial topological phase. Interestingly, the ferromagnetic state of Mn3Bi2Te6is a topological semimetal and it exhibits a topological transition from trivial to non-trivial induced by the magnetic transition. Our results enrich the Mn-Bi-Te family system, offer a new platform for studying topological phase transitions, and pave a new way to improve the working temperature of magnetically topological devices.
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BACKGROUND: The polymorphisms of VKORC1 and CYP2C9 play increasingly important roles in the inter-individual variability in warfarin dose. This study aimed to evaluate the feasibility of clinical application of pharmacogenetic-based warfarin-dosing algorithm in patients of Han nationality with rheumatic heart disease after valve replacement in a randomized and controlled trial. METHODS: One hundred and one consecutive patients of Han nationality with rheumatic heart disease undergoing valve surgery were enrolled and randomly assigned to an experimental group (n=50, based on CYP2C9 and VKORC1 genotypes, pharmacogenetic-based "predicted warfarin dose" for 3 days and then was adjusted to INR until stable warfarin maintenance dose) or a control group (n=51, 2.5mg/d for 3 days and then was adjusted to INR until stable warfarin maintenance dose). All included patients were followed for 50 days after initiation of warfarin therapy. The primary end-point was the time to reach a stable warfarin maintenance dose. RESULTS: During the follow-up, 84.0% patients in the experimental group and 58.8% patients in the control group received warfarin maintenance dose. Compared with control group, patients in the experimental group had shorter mean time elapse from initiation of warfarin therapy until warfarin maintenance dose (27.5±1.8 d versus 34.7±1.8 d, p<0.001). Cox regression revealed that group (HR for experimental versus control group: 1.568, 95%CI 1.103-3.284) and age were two significant variables related to the time elapse from initiation of warfarin therapy until warfarin maintenance dose. The predicted warfarin maintenance dose was prominently correlated with the actual warfarin maintenance dose (r=0.684, p<0.001). CONCLUSION: Based on CYP2C9 and VKORC1 genotypes, the pharmacogenetic-based warfarin-dosing algorithm may shorten the time elapse from initiation of warfarin therapy until warfarin maintenance dose. It is feasible for the clinical application of the pharmacogenetic-based warfarin-dosing algorithm in patients of Han nationality with rheumatic heart disease after valve replacement.
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Algoritmos , Implante de Prótese de Valva Cardíaca/métodos , Farmacogenética/métodos , Doenças Reumáticas/cirurgia , Varfarina/administração & dosagem , Varfarina/uso terapêutico , Adulto , Povo Asiático , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: To investigate the effectiveness of surgical approaches, outcomes and prognosis of aortic root pathology due to Stanford A aortic dissection. METHODS: Retrospective analysis the clinical data of 161 patients (122 male and 39 female, mean age of (44 ± 21) years) underwent surgical treatment for Stanford A aortic dissection between January 2001 and June 2011. There were 146 patients of acute aortic dissection and 15 patients of chronic aortic dissection. All the patients had aortic root pathologies that included commissural prolapsed in 140 cases, more than moderate aortic insufficiency in 75 cases, aortic sinus intima rupture in 15 cases, right and/or left coronary artery tearing in 8 cases, right and/or left coronary artery dissection in 16 cases, aortic root aneurysm in 31 cases. RESULTS: Aortic root replacement (Bentall procedures) were used in 72 cases, aortic root remodeling (including aortic valve replacement) in 80 cases, aortic root reimplantation (David procedure) in 9 cases. The cardiopulmonary bypass time was shorter in aortic root remodeling group ((193 ± 42) minutes) than the other two groups ((210 ± 61) minutes, (197 ± 34) minutes, F = 3.22, P = 0.04). The in-hospital mortality was 8.1% (13 cases), 5 cases (6.9%) in aortic root replacement group, 7 cases (8.8%) in aortic root remodeling group, 1 case in aortic root reimplantation. The cause of death included respiratory failure (4 cases), permanent neurological deficits (3 cases), multiple organ failure (4 cases), acute renal failure (2 cases). The survivors were followed up for 6 months to 6 years. There was no patient required reoperation for aortic root pathologies. There was no statistically significant difference between aortic root remodeling group and reimplantation group (P > 0.05). CONCLUSIONS: The surgical treatment for aortic root pathology due to Stanford A aortic dissection is challenging. Appropriate procedures according to the specialty of aortic root pathology can be performed with favorable functional results.
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Aorta/cirurgia , Aneurisma Aórtico/cirurgia , Dissecção Aórtica/cirurgia , Implante de Prótese Vascular/métodos , Adolescente , Adulto , Idoso , Aorta/patologia , Valva Aórtica/cirurgia , Feminino , Implante de Prótese de Valva Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Adulto JovemRESUMO
Topological magnons in a one-dimensional (1D) ferromagnetic Su-Schrieffer-Heeger (SSH) model with anisotropic exchange interactions are investigated. Apart from the intercellular isotropic Heisenberg interaction, the intercellular anisotropic exchange interactions, i.e. Dzyaloshinskii-Moriya interaction and pseudo-dipolar interaction, also can induce the emergence of the non-trivial phase with two degenerate in-gap edge states separately localized at the two ends of the 1D chain, while the intracellular interactions instead unfavors the topological phase. The interplay among them has synergistic effects on the topological phase transition, very different from that in the two-dimensional (2D) ferromagnet. These results demonstrate that the 1D magnons possess rich topological phase diagrams distinctly different from the electronic version of the SSH model and even the 2D magnons. Due to the low dimensional structural characteristics of this 1D topological magnonic system, the magnonic crystals can be constructed from bottom to top, which has important potential applications in the design of novel magnonic devices.
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OBJECTIVE: To observe the trend of change in perioperative blood glucose level in patients undergoing deep hypothermic circulatory arrest (DHCA), in order to evaluate the influencing factors of inciting hyperglycemia and the clinical effects of insulin control. METHODS: In the Department of Cardiothoracic Surgery of Changhai Hospital, 176 patients underwent aortic operation under DHCA from January 2000 to January 2010. Blood glucose, arterial blood gas and lactate levels were determined at four time points, including pre-cardiopulmonary bypass (CPB), pre-DHCA, post-DHCA, and at admission to intensive care unit (ICU). Hyperglycemia after surgery was controlled at the level of 6-8 mmol/L by intermittent subcutaneous injection or intravenous micropump injection of insulin. At the same time, the cumulative amount of insulin within 24 hours after surgery was recorded. RESULTS: The blood glucose (mmol/L) level at pre-DHCA time point was significantly higher than that of pre-CPB (9.62 ± 1.79 vs. 5.04 ± 1.401,P<0.05), and the blood glucose level was further elevated at the time point of post-DHCA (14.91 ± 2.36,P<0.01) and in-ICU (15.32 ± 2.47) compared with that of pre-CPB (P<0.01). The level of blood glucose elevation was positively correlated with blood lactate level. One hundred and thirty-four patients (76.1%) insulin was given with intravenous micropump due to poor effect of intermittent subcutaneous injection of insulin in controlling blood glucose. Among whom 30 patients (17.0%) developed the phenomenon of insulin resistance. Perioperative hyperglycemia during DHCA was associated with old age (≥ 50 years old), primary hypertension, serious aortic valve disease, diabetes or coronary heart disease, emergency operation, CPB time ≥ 3 hours and DHCA time ≥ 45 minutes. The cumulative amount of insulin within 24 hours after surgery was increased significantly. The results of blood glucose (mmol/L) in-ICU were as follows : age ≥ 50 years old or < 50 years old (18.66 ± 2.52 vs. 12.90 ± 2.27); hypertension with and without (18.98 ± 2.55 vs. 12.31 ± 2.34); serious aortic valve disease with and without (19.59 ± 2.95 vs. 12.13 ± 2.23); diabetes with and without (20.62 ± 1.76 vs. 11.75 ± 1.11); coronary heart disease with and without (19.77 ± 2.98 vs. 12.01 ± 2.02); emergency operation with and without (19.78 ± 1.97 vs. 12.23 ± 1.38); CPB time ≥ 3 hours or < 3 hours (19.86 ± 1.89 vs. 11.70 ± 1.15); DHCA time ≥ 45 minutes or < 45 minutes (19.92 ± 1.88 vs. 11.64 ± 1.12), and all of them should statistical difference (all P < 0.05). The cumulative amount of insulin (U) within 24 hours after surgery was as follows: age ≥ 50 years old or < 50 years old (169.5 ± 56.6 vs. 110.2 ± 38.5); hypertension with and without (171.6 ± 64.0 vs. 104.8 ± 34.3); aortic valve disease with and without (171.4 ± 36.8 vs. 109.4 ± 27.6); diabetes with and without (202.5 ± 46.7 vs. 100.4 ± 31.5); coronary heart disease with and without (178.5 ± 38.6 vs. 104.6 ± 26.4 ); emergency operation with and without (178.3 ± 35.7 vs. 102.7 ± 26.8); CPB time ≥ 3 hours or < 3 hours (168.6 ± 37.2 vs. 107.3 ± 27.5); DHCA time ≥ 45 minutes or < 45 minutes (172.5 ± 36.1 vs. 105.4 ± 28.7), and all of them showed significant statistical difference (all P < 0.05). and all of them showed significant statistical difference (all P < 0.05). CONCLUSION: DHCA may cause significant increase in perioperative blood glucose and lactate, and even may lead to insulin resistance. Patients often require continuous intravenous administration of large doses of insulin. Perioperative hyperglycemia during DHCA is related to many factors, which should be considered in control of blood glucose.
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Parada Circulatória Induzida por Hipotermia Profunda , Hiperglicemia/etiologia , Hiperglicemia/prevenção & controle , Assistência Perioperatória , Glicemia/metabolismo , Feminino , Humanos , Ácido Láctico/metabolismo , Masculino , Pessoa de Meia-IdadeRESUMO
Motivated by recent experimental observation [N. Z. Wang, et al., Inorg. Chem., 2019, 58, 9897], we investigated the electronic properties and chemical bonding in layered nitride-halide compounds ThNF and ThNCl using first-principles calculations to illustrate the interlayer interaction. The energy gaps and chemical valences of both compounds are in agreement with experimental data. The crystal orbital Hamiltonian population (COHP) and charge density differential analysis show that interlayer chemical bonding plays a more important role than that van der Waals interactions in ThNF and ThNCl, in contrast to isostructural ZrNCl and HfNCl. These results explain why it is difficult to intercalate ThNF and ThNCl with charged particles, as observed in experiments.
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The high-pressure (HP) properties of TlFeSe2are investigated based on the first-principles calculations combined with structure-searching method. The low-pressureC2/mphase will transform into the orthorhombicPnmaphase at 2 GPa, with 8% volume collapse, the insulator-metal transition and the bicollinear antiferromagnetic-to-nonmagnetic spin-crossover. At pressure higher than 8 GPa, the HPC2/mphase will become the ground state. BothPnmaphase and HPC2/mphase are constituted by one-dimensional chains of edge-sharing FeSe5tetragonal pyramids. Pressuring decrease the Se-Se bond length giving rise to the transition from [Se2]3-to [Se2]2-. Negative charge transfer causes the Fe2+with â¼2 µBmagnetic moment at ambient pressure and the nonmagnetic Fe1.5+at higher pressure. The Fermi surfaces of HP phases are also discussed.
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To clarify the role of glutathione S-transferases (GSTs; GSTM1 and GSTT1) status in susceptibility to coronary heart disease (CHD), a meta-analysis of published studies was performed. A total of 19 studies including 8020 cases and 11 501 controls were included in this meta-analysis. In a combined analysis, the relative risks for CHD of the GSTM1 null and GSTT1 null polymorphisms were 1.47 [95% confidence interval (CI): 1.08-2.01] and 1.26 (95% CI: 0.90-1.75), respectively. Three potential sources of heterogeneity including ethnicity, source of control and sample size of study were also assessed. However, no significant association was found in stratified analyses. By pooling data from eight studies (2909 cases and 3745 controls) that considered combinations of GSTT1 and GSTM1 genotypes, a statistically significant increased risk for CHD [odds ratio (OR = 2.38, 95% CI: 1.03-5.48)] was detected for individuals with combined deletion mutations in both genes compared with positive genotypes. Results from the meta-analysis of five studies on GSTs stratified according to smoking status showed an increased risk for individuals with null genotype (OR = 2.21, 95% CI: 1.24-3.92 for GSTM1 and OR = 3.29, 95% CI: 1.49-7.26 for GSTT1) versus non-null genotypes. This meta-analysis suggests that the GSTM1 null genotype may slightly increase the risk of CHD and that interaction between unfavourable GSTs genotypes may exist.
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Doença das Coronárias/genética , Glutationa Transferase/genética , Polimorfismo Genético , Intervalos de Confiança , Doença das Coronárias/epidemiologia , Predisposição Genética para Doença , Genótipo , Humanos , Razão de Chances , Fatores de RiscoRESUMO
OBJECTIVE: To improve the understanding of congenital quadricuspid aortic valve (QAV), explore its echocardiographic diagnostic value and summarize the methods and outcomes of surgical treatments. METHODS: The clinical data of 11 QAV patients from January 2000 to December 2008 were retrospectively analyzed. There were 9 males and 2 females with a mean operative age of (32±16) years (range: 4-55). RESULTS: In 766 patients undergoing aortic valve surgery, 11 were of congenital quadricuspid aortic valve (1.4%); cardiac pathology: infective endocarditis (n=1), left superior vena cava (n=1), aortic aneurysm (n=1), mitral prolapse (n=1) and tricuspid insufficiency (n=1). The patients of congenital QAV deformity was diagnosed by echocardiography (n=7), misdiagnosed as single valve (n=1), misdiagnosed as bicuspid valve (n=1) and misdiagnosed as rheumatic heart disease (n=2). Type B (n=7), Type A (n=2), Type F (n=1) and Type G (n=1). Eleven patients underwent the procedure of aortic valve replacement. And the concomitant procedures were aortic root broadening (n=1), ascending aortoplasty (n=1), mitral valvuloplasty (n=1) and tricuspid valvuloplasty (n=1). CONCLUSION: Quadricuspid aortic valve is rare in clinical practice. And echocardiography plays an important diagnostic role. Surgical replacement of aortic valve is the first-line therapy for these patients.