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1.
World J Urol ; 42(1): 67, 2024 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-38308763

RESUMEN

OBJECTIVE: To compare the stent-related symptoms (SRS) of three commonly used, readily accessible ureteric JJ stents after uncomplicated flexible ureteroscopic lithotripsy (FURL), in a prospective randomised controlled single-blind parallel-group study, in order to see whether structural difference might influence SRS. PATIENTS AND METHODS: Patients undergoing FURL were randomised into three groups: the Cook Group received conventional 6 F Cook Universa Soft JJ stents as control, the Kang Yi Bo (KYB) Group received 6 F KYB anti-reflux JJ stents, and the Urovision Group received 7 F Urovision Visiostar ESWL JJ stents. The ureteric stent symptom questionnaire (USSQ) was administered at 1 week, 4 weeks (before stent removal), and 5 weeks (one week after stent removal as baseline evaluation) after stent insertion. Both raw and baseline-adjusted USSQ domain subscores at 1 week and 4 weeks were compared. RESULTS: A total of 146 patients were included in the analysis. The KYB Group showed significantly lower P6&7 subscore yet higher urinary symptoms score 1 week and 4 weeks after stents insertion than both Cook and Urovision, whilst the Urovision Group achieved similar scores in most domains with Cook. CONCLUSIONS: Although the KYB anti-reflux JJ stent might prevent vesicoureteral reflux, it induces significantly stronger urinary symptoms, both at 1 week or 4 weeks after stent insertion, with or without baseline correction. Despite the unique triangular prismatic shape, the Urovision Visiostar stent does not cause heavier urinary symptoms or pain compared to the conventional cylinder shape counterparts.


Asunto(s)
Uréter , Humanos , Estudios Prospectivos , Método Simple Ciego , Dolor/etiología , Stents/efectos adversos
2.
BMC Urol ; 24(1): 169, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39118072

RESUMEN

INTRODUCTION: Inflammatory and immunological responses are reported involved in the pathogenesis and progression of obstructive nephropathy (ON). This study was designed to investigate the characteristics of peripheral immunity in patients with upper urinary tract urolithiasis and analyze the underlying associations with renal function. METHODS: Patients with unilateral upper urinary tract urolithiasis meeting the operation indications were prospectively enrolled. Preoperative circulating immune cells and inflammatory cytokines were detected in our clinical laboratory, and the indicators of renal function and calculi related parameters were particularly recorded. Patients were sectionalized into subgroups on the basis of the lesion of calculi. Characteristics of peripheral immunity in each subgroup were investigated by statistical approaches, and the underlying correlations with the degree of hydronephrosis (HN) and renal function were discussed in corresponding group. RESULTS: Patients with ureteral calculi presented severer HN compared with renal calculi, especial middle ureteral calculi, acting as the chief culprit of ON, exhibiting the highest serum creatine and blood urea nitrogen, most impaired estimated glomerular filtration rate, and severest HN. In addition, serum interleukin-8 (IL-8) and IL-6 were demonstrated presenting statistical differences between ureteral calculi and renal calculi patients, exhibiting underlying values in comprehending ON. However, circulating immune cells were demonstrated no obvious differences among groups. CONCLUSIONS: Circulating inflammatory cytokines, referred in particular to serum IL-8 and IL-6 were partially associated with kidney injury in patients with upper urinary tract urolithiasis. But the specific influences and mechanisms between them needed to be investigated furthermore.


Asunto(s)
Cálculos Ureterales , Humanos , Masculino , Femenino , Persona de Mediana Edad , Cálculos Ureterales/inmunología , Cálculos Ureterales/complicaciones , Adulto , Estudios Prospectivos , Cálculos Renales/inmunología , Riñón/inmunología , Riñón/fisiopatología , Hidronefrosis/sangre , Hidronefrosis/etiología , Hidronefrosis/inmunología , Urolitiasis/inmunología , Citocinas/sangre , Anciano , Estudios Transversales
3.
Environ Toxicol ; 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38476113

RESUMEN

This study investigates Astragalus's efficacy as a novel therapeutic option for primary liver cancer (PLC), capitalizing on its anti-inflammatory and antiviral effects. We utilized network pharmacology to unveil Astragalus's potential targets against PLC, revealing significant gene expression alterations in treated samples-20 genes were up-regulated, and 20 were down-regulated compared to controls. Our analysis extended to single-cell resolution, where we processed scRNA-seq data to discern 15 unique cell clusters within the immune, malignant, and stromal compartments through advanced algorithms like UMAP and tSNE. To delve deeper into the functional implications of these gene expression changes, we conducted comprehensive gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses, alongside Gene Set Variation Analysis, to elucidate the biological processes and pathways involved. Further, we constructed protein-protein interaction networks to visualize the intricate molecular interplay, highlighting the down-regulation of MT1E in PLC cells, a finding corroborated by quantitative polymerase chain reaction. Molecular docking studies affirmed the potent interaction between Astragalus's active compounds and MT proteins, underscoring a targeted therapeutic mechanism. Our investigation also encompassed a detailed cellular landscape analysis, identifying nine cell subgroups related to MT1 expression and specifying five cell subsets through the SingleR package. Advanced trajectory and cell-cell interaction analyses offered deeper insights into the dynamics of MT1-associated cellular subpopulations. This comprehensive methodology not only underpins Astragalus's promising role in PLC treatment but also advances our understanding of its molecular and cellular mechanisms, paving the way for targeted therapeutic strategies.

4.
Int Arch Allergy Immunol ; 184(11): 1090-1098, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37598672

RESUMEN

INTRODUCTION: Serum cotinine and magnesium intake are often associated with childhood asthma. This study evaluated the interaction between serum cotinine and magnesium intake and childhood asthma. METHODS: This cross-sectional study included 14,159 subjects from the National Health and Nutrition Examination Survey 2005-2018. Serum cotinine levels were classified according to the lower quartile: ≤0.2089 ng/mL as low level and >0.2089 ng/mL as high level. Magnesium intake was categorized as high (>98 mg/1,000 kcal) or low level (≤98 mg/1,000 kcal) based on the upper quartile. Weighted logistic regression analyses were adopted to analyze the association between cotinine, magnesium intake, and childhood asthma. Additionally, the combined effect of cotinine and magnesium intake on childhood asthma risk was examined. The stratified analyses were based on gender, body mass index, and family history of asthma to further examine the relationship between cotinine, magnesium intake, and childhood asthma. RESULTS: The prevalence of asthma was approximately 17.56%. Compared to low-level cotinine, high-level cotinine was associated with asthma (odds ratio [OR] = 1.25, 95% confidence interval (CI): 1.04-1.50). Low-level magnesium intake was related to asthma compared with high-level magnesium intake (OR = 1.21, 95% CI: 1.04-1.40). Using interaction analysis, we also found that the combined effect of cotinine and magnesium intake was associated with childhood asthma risk, and the interaction between high-level cotinine and low-level magnesium intake was associated with the highest risk of childhood asthma (OR = 1.35, 95% CI: 1.04-1.74). Additionally, this interaction was also found in males, overweight/non-overweight, and those with family history of asthma. CONCLUSION: There was an interaction between serum cotinine and magnesium intake on childhood asthma. The results suggested that implementing smoking bans in certain settings (e.g., communities, schools) and promoting the consumption of magnesium-rich foods may be effective strategies for preventing childhood asthma.


Asunto(s)
Asma , Contaminación por Humo de Tabaco , Masculino , Humanos , Encuestas Nutricionales , Cotinina , Estudios Transversales , Magnesio , Asma/diagnóstico
5.
BMC Infect Dis ; 23(1): 192, 2023 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-36997914

RESUMEN

BACKGROUND: Streptococcus dysgalactiae subsp. dysgalactiae has been identified as an animal pathogen that is thought to occur only in animal populations. Between 2009 and 2022, humans infected with SDSD were reported rarely. There is a lack of details on the natural history, clinical features, and management of disease caused by this pathogen. This case outlines a human SDSD with muscle aches and progressive loss of muscle strength leading to immobility and multi-organ dysfunction syndrome. CASE PRESENTATION: She presented with muscle pain and weakness, and later developed a sore throat, headache and fever with a maximum temperature of 40.5 °C. The muscle strength of the extremities gradually decreased to grade 1 and the patient was unable to move on his own. Next-generation blood sequencing and multi-culture confirmed the presence of Streptococcus dysgalactiae and Streptococcus dysgalactiae subsp. Dysgalactiae, respectively. A Sequential Organ Failure Assessment score of 6 indicated septicemia, and therapeutic antibiotics were prescribed empirically. After 19 days of inpatient treatment, the patient's condition greatly improved and completely recovered within a month. CONCLUSION: Symptoms of Streptococcus dysgalactiae subsp. dysgalactiae presenting with progressive limb weakness resemble polymyositis, so a precise differential diagnosis is essential. Multidisciplinary consultation is helpful when polymyositis cannot be ruled out and facilitates the choice of an optimal treatment protocol. In the context of this case, penicillin is an effective antibiotic for Streptococcus dysgalactiae subsp. dysgalactiae infection.


Asunto(s)
Infecciones Estreptocócicas , Animales , Femenino , Humanos , Infecciones Estreptocócicas/diagnóstico , Infecciones Estreptocócicas/tratamiento farmacológico , Insuficiencia Multiorgánica , Extremidades
6.
BMC Med Inform Decis Mak ; 23(1): 179, 2023 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-37697312

RESUMEN

Addressing the current complexities, costs, and adherence issues in the detection of forward head posture (FHP), our study conducted an exhaustive epidemiologic investigation, incorporating a comprehensive posture screening process for each participant in China. This research introduces an avant-garde, machine learning-based non-contact method for the accurate discernment of FHP. Our approach elevates detection accuracy by leveraging body landmarks identified from human images, followed by the application of a genetic algorithm for precise feature identification and posture estimation. Observational data corroborates the superior efficacy of the Extra Tree Classifier technique in FHP detection, attaining an accuracy of 82.4%, a specificity of 85.5%, and a positive predictive value of 90.2%. Our model affords a rapid, effective solution for FHP identification, spotlighting the transformative potential of the convergence of feature point recognition and genetic algorithms in non-contact posture detection. The expansive potential and paramount importance of these applications in this niche field are therefore underscored.


Asunto(s)
Puntos Anatómicos de Referencia , Pueblos del Este de Asia , Postura , Adolescente , Humanos , Pueblo Asiatico , Aprendizaje Automático , Postura/fisiología , Algoritmos
7.
Ren Fail ; 45(2): 2275714, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37929948

RESUMEN

This study evaluated the clinical value of color Doppler ultrasound-guided percutaneous nephrolithotomy (PCNL) in avoiding bleeding caused by punctured blood vessels. Herein, we retrospectively included patients who underwent color Doppler ultrasound-guided PCNL or PCNL using the conventional channel technique from August 2018 to August 2022. The clinical characteristics of patients during surgery, complications, and hospital stay were recorded and compared. Overall, 228 patients were enrolled, with 126 patients (age, 47.6 ± 13.2 years; men: 57.14%) in the color Doppler ultrasound-guided PCNL group and 102 patients (age, 46.6 ± 12.3 years) in the B-mode ultrasound-guided puncture group. The total operation time (63.5 ± 15.5 vs. 61.3 ± 16.3 min, p = .5236) and stone clearance rate (86.50% vs. 83.33%, p = .7139) were similar between the two groups. However, the puncture time for the color Doppler ultrasound-guided PCNL group was longer than that for the B-mode ultrasound-guided puncture group (5.1 ± 2.3 vs. 2.6 ± 1.6 min, p = .0019). Moreover, the length of postoperative hospital stay in the color Doppler ultrasound-guided PCNL group reduced significantly by ∼1 day compared with that in the B-mode ultrasound-guided puncture group (4.5 ± 1.6 vs. 5.6 ± 2.1 days, p = .0087). The blood transfusion rate (1.58% vs. 4.9%, p = .0399), sedation-related adverse event rate (0.79% vs. 2.9%, p = .0332), perineal hematoma incidence (0% vs. 2.94%, p < .0001), and serum decreased hemoglobin levels (12.2 ± 9.7 vs. 23.5 ± 10.1 g/L, p < .001) after color Doppler ultrasound-guided PCNL were significantly lower than those after B-mode ultrasound-guided puncture. The stone clearance rate was similar between the two groups, with a similar operation time. Moreover, color Doppler ultrasound-guided PCNL shortened the postoperative hospital stay and decreased Hb levels, blood transfusion rate, and perineal hematoma incidence.


Asunto(s)
Cálculos Renales , Nefrolitotomía Percutánea , Nefrostomía Percutánea , Masculino , Humanos , Adulto , Persona de Mediana Edad , Nefrolitotomía Percutánea/efectos adversos , Nefrolitotomía Percutánea/métodos , Estudios Retrospectivos , Cálculos Renales/diagnóstico por imagen , Cálculos Renales/cirugía , Nefrostomía Percutánea/efectos adversos , Nefrostomía Percutánea/métodos , Resultado del Tratamiento , Ultrasonografía Doppler en Color , Hematoma/etiología
8.
Biochem Biophys Res Commun ; 617(Pt 1): 60-67, 2022 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-35679712

RESUMEN

Acute lung injury (ALI) is a life-threatening disease caused by the severe and acute response of the lungs to a variety of direct and indirect insults. Patients with ALI are currently treated mainly with respiratory support due to inadequate understanding of ALI progression. Alveolar epithelial cells produced thymic stromal lymphopoietin (TSLP) has been proved to worsen ALI by triggering airway inflammation. However, the regulation mechanism of TSLP expression remains unclear. In this study, we identified the crucial role played by circNCLN in lipopolysaccharide (LPS)-induced ALI. We demonstrated for the first time that miR-291a-3p could directly bind to the 3'UTR of TSLP and suppress TSLP expression in alveolar epithelial cells. Mechanistically, our data identified that circNCLN acts as a molecular sponge to antagonize miR-291a-3p and thereby maintaining the expression of TSLP in alveolar epithelial cells. Importantly, targeting circNCLN by its antisense oligonucleotide (ASO) markedly alleviated LPS-induced ALI. Therefore, our results suggested that circNCLN/miR-291a-3p/TSLP axis may be an important signaling in LPS-induced ALI and circNCLN inhibition may serve as a potential treatment of ALI.


Asunto(s)
Lesión Pulmonar Aguda , MicroARNs , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/genética , Citocinas/metabolismo , Humanos , Lipopolisacáridos/metabolismo , Pulmón/metabolismo , Linfopoyetina del Estroma Tímico
9.
Inorg Chem ; 61(11): 4555-4560, 2022 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-35257588

RESUMEN

Herein, by replacement of the linear terephthalate linker with the bending 2,5-thiophenedicarboxylate (tdc2-) linker in the typical (3,9)-connected metal-organic framework, with a reduced 8-connected hydroxyl-centered trinuclear cluster, a new (3,8)-connected network, [Ni3(µ3-OH)(tdc)3(tpp)] [DZU-1; tpp = 2,4,6-tris(4-pyridyl)pyridine], was synthesized. The modified pore environment enables DZU-1 to selectively adsorb C2H2 over CO2 in an efficient manner.

10.
Phys Chem Chem Phys ; 24(17): 10114-10123, 2022 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-35416816

RESUMEN

We investigate the low-lying electronic states and feasibility of direct laser cooling of AsH, SbH and BiH by means of the highly accurate ab initio and dynamical methods with the inclusion of the spin-orbit coupling effects. Twelve low-lying Ω states for each of them are computed using the internally contracted multireference configuration interaction method. Our computed spectroscopic constants are in excellent agreement with the available experimental data. The calculated spin-orbit matrix elements are large enough, and thus the intersystem crossings from the A3Π state and the transitions to the a1Δ2 state should be considered in laser cooling. We find that, from AsH to BiH, the location of the crossing point between the A3Π and 5Σ- states moves down towards the ground vibrational level of A3Π along with enhanced spin-orbit coupling effects, which increases the difficulty of laser cooling heavier hydrides. An empirical law of "crossing point shifting down" down a group in the periodic table is generalized, which may become a helpful caveat when cooling diatomic molecules containing heavier elements. By choosing specific spin-orbit states, we construct feasible laser cooling schemes for AsH and SbH based on the A3Π2 → X3Σ-1 transitions, which feature very large vibrational branching ratios R00 (AsH: 0.9662; SbH: 0.9248) and short radiative lifetimes (AsH: 914 ns; SbH: 883 ns). In particular, a constructed laser cooling scheme for AsH is able to scatter 1.24 × 104 photons, whereas that for SbH can scatter 8.60 × 103 photons, which are enough to cool AsH and SbH to the ultracold regime. The present work demonstrates the importance of intersystem crossings and spin-orbit couplings in molecular laser cooling.

11.
J Am Chem Soc ; 143(3): 1485-1492, 2021 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-33439004

RESUMEN

Ethylene production from C2 hydrocarbon mixtures through one separation step is desirable but challenging because of the similar size and physical properties of acetylene, ethylene, and ethane. Herein, we report three new isostructural porous coordination networks (NPU-1, NPU-2, NPU-3; NPU represents Northwestern Polytechnical University) that are sustained by 9-connected nodes based upon a hexanuclear metal cluster of composition [Mn6(µ3-O)2(CH3COO)3]6+. NPU-1/2/3 exhibit a dual cage structure that was systematically fine-tuned in terms of cage size to realize selective adsorption of C2H2 and C2H6 over C2H4. Dynamic breakthrough experiments demonstrated that NPU-1 produces ethylene in >99.9% purity from a three-component gas mixture (1:1:1 C2H2/C2H4/C2H6). Molecular modeling studies revealed that the dual adsorption preference for C2H2 and C2H6 over C2H4 originates from (a) strong hydrogen-bonding interactions between electronegative carboxylate O atoms and C2H2 molecules in one cage and (b) multiple non-covalent interactions between the organic linkers of the host network and C2H6 molecules in the second cage.

12.
Cancer Cell Int ; 21(1): 129, 2021 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-33622324

RESUMEN

BACKGROUND: Renal cell carcinoma (RCC) is one of the most common malignant tumors originating from the renal parenchymal urinary epithelial system. Tripartite motif 47 (TRIM47) is a member of the TRIM family proteins, which has E3 ligase activity and has been demonstrated to be involved in the occurrence and prognosis of many tumors. The main purpose of this study is to explore the role and potential mechanism of TRIM47 in promoting malignant biological behavior of RCC. MATERIALS AND METHODS: TRIM47 mRNA and protein levels in human renal cancer and paired normal adjacent tissues were detected by qRT-PCR and Western blot. The effects of TRIM47 knockdown and overexpression in renal cell carcinoma cells on cell proliferation, invasion and xenograft tumor growth in nude mice were analyzed. The molecular mechanism was explored by mass spectrometric exploration,Western blot and immunoprecipitation assays. RESULTS: TRIM47 promoted RCC cell proliferation in vitro and in vivo as an oncogene. Mechanistically, TRIM47 exerted an E3 ligase activity by interacting with P53 protein to increase its ubiquitination and degradation, which further promoted the malignant biological behavior of RCC. CONCLUSIONS: Our study demonstrated that the TRIM47-P53 axis played a functional role in RCC progression and suggested a potential therapeutic target for RCC.

13.
Chemistry ; 27(36): 9446-9453, 2021 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-33837618

RESUMEN

Rigid molecular sieving materials are the ideal candidates for gas separation (e. g., C2 H2 /C2 H4 ) due to their ultrahigh adsorption selectivity and the absence of gas co-adsorption. However, the absolute molecular sieving effect for C2 H2 /C2 H4 separation has rarely been realized because of their similar physicochemical properties. Herein, we demonstrate the absolute molecular sieving of C2 H2 from C2 H4 by a rigid ultra-microporous metal-organic framework (F-PYMO-Cu) with 1D regular channels (pore size of ca. 3.4 Å). F-PYMO-Cu exhibited moderate acetylene uptake (35.5 cm3 /cm3 ), but very low ethylene uptake (0.55 cm3 /cm3 ) at 298 K and 1 bar, yielding the second highest C2 H2 /C2 H4 uptake ratio of 63.6 up to now. One-step C2 H4 production from a binary mixture of C2 H2 /C2 H4 and a ternary mixture of C2 H2 /CO2 /C2 H4 at 298 K was achieved and verified by dynamic breakthrough experiments. Coupled with excellent thermal and water stability, F-PYMO-Cu could be a promising candidate for industrial C2 separation tasks.

14.
Chemistry ; 27(50): 12753-12757, 2021 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-34173276

RESUMEN

Low-concentration ethane capture is crucial for environmental protection and natural gas purification. The ideal physisorbent with strong C2 H6 interaction and large C2 H6 uptake at low-concentration level has rarely been reported, due to the large pKa value and small quadrupole moment of C2 H6 . Herein, we demonstrate the perfectly size matching between the ultramicropore (pore size of 4.6 Å) and ethane (kinetic diameter of 4.4 Å) in a nickel pyridine-4-carboxylate metal-organic framework (IISERP-MOF2), which enables the record-breaking performance for low concentration C2 H6 capture. IISERP-MOF2 exhibits the large C2 H6 adsorption enthalpy of 56.7 kJ/mol, and record-high C2 H6 uptake at low pressure of 0.01-0.1 bar and 298 K (1.8 mmol/g at 0.01 bar). Molecule simulations and C2 H6 -loading crystal structure analysis revealed that the maximized interaction sites in IISERP-MOF2 with ethane molecule originates the strong C2 H6 adsorption. The dynamic breakthrough experiments for gas mixtures of C2 H6 /N2 (1/999, v/v) and C2 H6 /CH4 (5/95, v/v) proved the excellent low-concentration C2 H6 capture performance.


Asunto(s)
Gases , Estructuras Metalorgánicas , Adsorción , Termodinámica
15.
Phys Chem Chem Phys ; 23(10): 6141-6153, 2021 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-33684184

RESUMEN

Recent studies on the exothermic complex-forming reactions have improved our understanding of complex-forming reactions greatly, however, so far a similar level of study on endothermic ones has been rather limited. In this work, the endothermic complex-forming reaction Si(1D) + H2 → SiH + H and its deuterated isotopic variant are investigated by quantum dynamics (QD) and ring polymer molecular dynamics (RPMD) calculations on a new global ab initio potential energy surface (PES) for the ground electronic state, which is constructed based on 8996 symmetry unique points computed at the icMRCI+Q/aug-cc-pVQZ level. The PES reproduces our ab initio data very well in the dynamically important regions, on which the ro-vibrational energy levels of SiH2 are calculated and general good agreement with experiment is obtained. The integral cross sections and product angular and state distributions are computed in a wide range of collision energies, and interesting dynamics behaviors are revealed. The rate coefficients are also investigated, which display an exponential rise from 2.09 × 10-20 to 6.00 × 10-12 cm3 s-1 for the Si(1D) + H2 reaction as the temperature increases from 300 to 1500 K, in contrast to the nearly temperature-independent behavior of exothermic complex-forming reactions. In addition, the applicability of the RPMD approach is demonstrated, and the kinetic isotope effect is investigated, the ratio of which decreases from 7.89 (300 K) to 1.70 (1500 K). The effects of tunneling and initial rotational excitation are also discussed.

16.
Inorg Chem ; 59(18): 13019-13023, 2020 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-32865397

RESUMEN

The pore-size effect on ethane adsorption and ethane/ethylene separation in three isostructural metal azolate frameworks (MAF-123-Mn/Zn/Cu) were thoroughly investigated. MAF-123-Mn/Zn/Cu were synthesized by the solvothermal method on a gram scale. Decreasing the pore size from 6.1 to 4.9 Å leads to an increase in the ethane adsorption energy from 23 to 27.5 kJ mol-1 and further ethane/ethylene separation efficiency. Molecule simulations revealed that a shorter ethane-framework interaction distance in MAF-123-Zn than that in MAF-123-Mn is responsible for the increased adsorption energy. Dynamic breakthrough experiments manifest that these metal azolate frameworks can effectively produce high-purity ethylene from ethane in one adsorption step.

17.
J Phys Chem A ; 124(32): 6536-6543, 2020 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-32662997

RESUMEN

The formic acid dimer (FAD) is an important benchmark system for understanding the double hydrogen transfer process. Most recently, Zhang et al. measured a few tunneling splittings upon fundamental excitation of FAD precisely (Zhang, Y. et al. J. Chem. Phys. 2017, 146, 244306); however, relevant theoretical studies are very limited. Here, we present a multidimensional quantum dynamics study on mode-specific tunneling splittings upon fundamental excitation in FAD with an efficient theoretical scheme developed by our group in which the process-oriented basis function customization strategy is combined with the preconditioned inexact spectral transform method. Various mode-specific tunneling splittings upon fundamental excitation are systematically calculated, and interesting mode-specific excitation effects on tunneling rate are identified. In particular, the calculated tunneling splittings for the ν22 and ν21 states are in good agreement with experiment, and the remarkable mode-specific suppression effects upon excitation should result from that the antisymmetric vibrational modes hinder the concerted double H-transfer. The present work is helpful to acquire a better understanding of the mode-specific excitation effects on tunneling processes.

18.
J Phys Chem A ; 124(5): 801-809, 2020 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-31958231

RESUMEN

We present an in-depth theoretical study of the C(1D) + HD (v = 0, j = 0) → CD (CH) (v', j') + H (D) reaction using a time-dependent wave packet method with full Coriolis coupling on the Zhang-Ma-Bian potential energy surfaces (PESs) recently constructed by our group. The integral cross sections (ICS), differential cross sections, CD/CH branching ratios, and product state distributions are calculated over a wide range of collision energies. We find that the vibrational branching ratio defined as ICS(v'=1)/ICS(v'=0) obtained from the b̃1A″ PES is much smaller than that from the ã1A' PES for both product channels, which may be attributed to the dynamical effects of the conical intersection regulated (CI-R) intermediate on the b̃1A″ PES. The collision energy dependence of CD/CH branching ratios displays oscillatory structures, which may be caused by the resonance states supported by the wells on the PESs. The high-temperature rate coefficients are also obtained and compared with previous results. The role of the excited-state PESs is also discussed.

19.
J Chem Phys ; 153(5): 054309, 2020 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-32770895

RESUMEN

We present accurate quantum dynamics calculations on vinylidene-d2 (fully deuterated vinylidene) isomerization. This is achieved by large-scale parallel computations with an efficient theoretical scheme developed by us in which basis functions are customized for the deuterium migration process. Mode-specific permutation tunneling splittings of vinylidene-d2 states are reported here for the first time, and evident isotope effects are revealed. The A1 ', B2 ', A1 ″, and B2 ″ symmetric vinylidene-d2 states are calculated, and the peaks recently observed in the cryo-SEVI spectra are analyzed, with very good agreement between theory and experiment achieved for the energy levels. In addition, a few vinylidene-d2 states beyond the experimental energy region are reported. Our studies are helpful for acquiring a better understanding of isotope effects in the double-hydrogen migration processes.

20.
Cardiovasc Drugs Ther ; 33(1): 45-54, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30675709

RESUMEN

Myocardial ischemia/reperfusion (I/R) injury is a serious threat to the health of people around the world. Recent evidence has indicated that high-mobility group box-1 (HMGB1) is involved in I/R-induced inflammation, and inflammation can cause necroptosis of cells. Interestingly, dexmedetomidine (DEX) has anti-inflammatory properties. Therefore, we speculated that DEX preconditioning may suppress H/R-induced necroptosis by inhibiting expression of HMGB1 in cardiomyocytes. We found that hypoxia/reoxygenation (H/R) significantly increased cellular damage, as measured by cell viability (100 ± 3.26% vs. 53.33 ± 3.29, p < 0.01), CK-MB (1 vs. 3.25 ± 0.26, p < 0.01), cTnI (1 vs. 2.69 ± 0.31, p < 0.01), inflammation as indicated by TNF-α (1 ± 0.09 vs. 2.57 ± 0.12, p < 0.01), IL-1ß (1 ± 0.33 vs. 3.87 ± 0.41, p < 0.01) and IL-6 (1 ± 0.36 vs. 3.60 ± 0.45, p < 0.01), and necroptosis, which were accompanied by significantly increased protein levels of HMGB1. These changes [cellular damage as measured by cell viability (53.33 ± 3.29% vs. 67.59 ± 2.69%, p < 0.01), CK-MB (3.25 ± 0.26 vs. 2.27 ± 0.22, p < 0.01), cTnI (2.69 ± 0.31 vs. 1.90 ± 0.25, p < 0.01), inflammation as indicated by TNF-α (2.57 ± 0.12 vs. 1.75 ± 0.15, p < 0.01), IL-1ß (3.87 ± 0.41 vs. 2.09 ± 0.36, p < 0.01) and IL-6 (3.60 ± 0.45 vs. 2.21 ± 0.39, p < 0.01), and necroptosis proteins] were inhibited by DEX preconditioning. We also found that silencing expression of HMGB1 reinforced the protective effects of DEX preconditioning and overexpression of HMGB1 counteracted the protective effects of DEX preconditioning. Thus, we concluded that DEX preconditioning inhibits H/R-induced necroptosis by inhibiting expression of HMGB1 in cardiomyocytes.


Asunto(s)
Antiinflamatorios/farmacología , Dexmedetomidina/farmacología , Proteína HMGB1/antagonistas & inhibidores , Mediadores de Inflamación/antagonistas & inhibidores , Daño por Reperfusión Miocárdica/prevención & control , Miocitos Cardíacos/efectos de los fármacos , Animales , Muerte Celular/efectos de los fármacos , Hipoxia de la Célula , Línea Celular , Microambiente Celular , Citocinas/metabolismo , Proteína HMGB1/genética , Proteína HMGB1/metabolismo , Mediadores de Inflamación/metabolismo , Daño por Reperfusión Miocárdica/metabolismo , Daño por Reperfusión Miocárdica/patología , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Ratas , Transducción de Señal/efectos de los fármacos
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