Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 71
Filtrar
1.
Artículo en Inglés | MEDLINE | ID: mdl-38658508

RESUMEN

The transformation of solid wastes from industrial production into effective adsorbents could significantly contribute to wastewater treatment. In this study, after acidizing and burning soft scale (SS) from coal gasification system, two magnetic adsorbents (mag-ASS and mag-BASS) were prepared via the combination of magnetite with ultrasonic, respectively. The treatment effects of mag-ASS and mag-BASS were then investigated for simulated wastewater containing macromolecular organic matter [i.e., methylene blue (MB)] and Ca2+. The results indicated that the pseudo second order kinetic, Elovich, Freundlich, Langmuir and Temkin model could well describe the adsorption behavior of MB and Ca2+ onto mag-ASS and mag-BASS. The maximum adsorption capacities of mag-ASS for MB and mag-BASS for Ca2+ were 600.53 mg/g and 102.54 mg/g, respectively. Surprisingly, the adsorption abilities of mag-ASS for MB and mag-BASS for Ca2+ show significantly higher than the others. The adsorption mechanisms of MB mainly included electrostatic interaction, π-π conjugate interaction and cation exchange, while those of Ca2+ were mainly electrostatic interaction and cation exchange. The diffusion of MB and Ca2+ onto the magnetic adsorbents might be controlled by the combined effects of intraparticle and liquid film diffusion. There was no significant reduction in adsorption capacity after 8 cycles of adsorption and desorption, indicating that SS-based magnetic adsorbents had good recyclability and stability. Moreover, the removal efficiency of mag-BASS for total hardness and total organic carbon in real coal gasification gray water (CGGW) was 82.60 and 64.10%, respectively. The treatment of CGGW and the resource of wastes would significantly promote the reasonable disposal of coal gasification scales.

2.
Org Lett ; 26(10): 2108-2113, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38440974

RESUMEN

A metal-free photosensitized 1,2-imino-sulfamoylation of olefins by employing a tailor-made sulfamoyl carbamate as the difunctionalization reagent has been established. This protocol exhibits versatility across a broad substrate scope, including aryl and aliphatic alkenes, leading to the synthesis of diverse ß-imino sulfonamides in moderate to good yields. This method is characterized by its metal-free reaction system, mild reaction conditions, excellent regioselectivity, and high atom economy, serving as a promising platform for the preparation of ß-amino sulfonamide-containing molecules, particularly in the context of drug discovery.

3.
Org Lett ; 25(49): 8824-8828, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38032230

RESUMEN

Herein, a visible-light-induced nickel-catalyzed cross-coupling of aryl bromide with nitrile has been reported. By utilization of readily available nitriles as carbonyl precursors, a range of structurally diverse aryl ketones were facilely constructed. The synthetic simplicity, mild reaction conditions, and acidic functional group tolerance would broaden the synthetic utilities of this developed protocol as an expedient alternative to Grignard/organolithium protocols.

4.
Org Lett ; 25(38): 7062-7066, 2023 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-37726866

RESUMEN

A visible-light-induced radical relay strategy to access heterocycles bearing a monofluoromethylsufonyl moiety is reported, with PhI(OCOCH2F)2 as the CH2F radical precursor and DABSO as the SO2 source. A range of oxindoles, containing a CH2FSO2CH2- group at the C3 position, were synthesized from N-arylacrylamides in up to 97% yields. The protocol features catalyst-free photochemical tandem, mild reaction conditions, broad functional group compatibility, and good to excellent yields.

5.
Org Lett ; 25(32): 6077-6081, 2023 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-37550862

RESUMEN

Herein, we report a visible-light-induced, palladium-catalyzed desaturation/sulfonation cascade, offering a concise route to a series of highly valuable 4-sulfonyltetrahydropyridine scaffolds from inexpensive and readily available piperidine derivatives with sodium sulfinates. The key to the success of this transformation is the well-designed sequence of palladium-mediated 1,5-hydrogen atom transfer/ß-hydride elimination/allylic sulfonation process, which demonstrates the synthetic potentials for orchestrating synthetic events by rationally taking advantage of varied catalytic modes.

6.
Chem Commun (Camb) ; 59(67): 10125-10128, 2023 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-37491978

RESUMEN

Reported herein is the design and development of a new photo-induced amidation protocol with the readily available N-chlorosulfonyl carbamate as an effective amidyl-radical precursor, which could be readily prepared from commercial low-cost chlorosulfonyl isocyanate (CSI) and alcohol feedstocks. The synthetic potency of this developed protocol was well demonstrated by direct amidation of various quinoxalin-2(1H)-ones. The protocol could be further streamlined by implementing a one-pot/two-step/three-component process of CSI, alcohol, and quinoxalin-2(1H)-one, with significantly improved reaction efficiency. This methodology offers an intriguing opportunity for rapid expansion of nitrogen-containing molecular complexity, thus inspiring comprehensive exploration of a new reaction mode of CSI reagent.

7.
Org Lett ; 25(22): 4056-4060, 2023 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-37255226

RESUMEN

A Giese reaction of aryl bromides with electron-deficient alkenes was developed, enabled by a dual catalyst system containing NiII complex and IrIII photocatalyst. This protocol could accommodate a variety of aryl bromides and electron-deficient alkenes, delivering the conjugate adducts in up to 97% yield. The utilization of photoexcited (dtbbpy)NiII(aryl)Br intermediate as an aryl radical source allows this novel transformation of aryl halides, thus expanding the chemical space of excited nickel catalysis.


Asunto(s)
Alquenos , Bromuros , Catálisis , Níquel , Electrones
8.
Org Lett ; 25(10): 1782-1786, 2023 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-36884012

RESUMEN

A metal-free photosensitized three-component reaction of oxime esters, alkenes, and DABCO·(SO2)2 was developed. This protocol could accommodate a wide substrate scope, including activated and unactivated alkenes and aryl and aliphatic carboxylic acid oxime esters, delivering a broad range of ß-amino sulfones in moderate to high yields. The insertion of SO2 as a linker moiety allows the manipulation of the functionality in the reaction process, expanding the utility of oxime esters as bifunctional reagents.

9.
Chemosphere ; 311(Pt 1): 136898, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36257394

RESUMEN

To prevent the scale formation in the equipments and pipelines after pre-treated coal gasification gray water (CGGW) entering the reuse system and reduce the influence of various pollutants in the effluent on subsequent biochemical treatment, this study presented a coupled use of pulse electrocoagulation (PEC) and chemical precipitation (CP) coupling method for the pretreatment of coal gasification gray water (CGGW). In addition, the operation parameters of PEC and the reaction conditions of PEC-CP were optimized based on iron plate as electrode and total hardness, turbidity and sludge yield as assessment indicators. Due to the formation of multi-hydroxyl iron by several minutes of pulse current, and the addition of pH regulator and coagulant aid, the efficient removal of various ions, hardness and turbidity was significantly reduced via various mechanism such as redox, precipitation, adsorption and coagulation reaction. The result indicated that under the optimal operation conditions, the total hardness, turbidity, and Fen+ of PEC-CP effluents were 275.0 mg/L, 3.0 NTU and 5.6 mg/L, respectively and sludge amount was 0.88 kg/m3. The removal rates of Si, B, Mn, Ba, COD, NPOC and NH4+-N by PEC-CP reached 80.0%, 75.4%, 97.0%, 99.8%, 35.0%, 33.6% and 23.8%, respectively. The present results suggested that the CGGW pretreatment effluents could be not only reused directly, but also greatly alleviate the scaling problem of water pipeline and coal gasification production facilities.


Asunto(s)
Contaminantes Ambientales , Contaminantes Químicos del Agua , Carbón Mineral , Aguas Residuales , Aguas del Alcantarillado , Agua , Precipitación Química , Electrocoagulación , Hierro , Contaminantes Químicos del Agua/análisis , Eliminación de Residuos Líquidos/métodos
10.
Neural Regen Res ; 18(6): 1293-1299, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36453414

RESUMEN

Treadmill exercise and mesenchymal stem cell transplantation are both practical and effective methods for the treatment of cerebral ischemia. However, whether there is a synergistic effect between the two remains unclear. In this study, we established rat models of ischemia/reperfusion injury by occlusion of the middle cerebral artery for 2 hours and reperfusion for 24 hours. Rat models were perfused with bone marrow mesenchymal stem cell-derived exosomes (MSC-exos) via the tail vein and underwent 14 successive days of treadmill exercise. Neurological assessment, histopathology, and immunohistochemistry results revealed decreased neuronal apoptosis and cerebral infarct volume, evident synaptic formation and axonal regeneration, and remarkably recovered neurological function in rats subjected to treadmill exercise and MSC-exos treatment. These effects were superior to those in rats subjected to treadmill exercise or MSC-exos treatment alone. Mechanistically, further investigation revealed that the activation of JNK1/c-Jun signaling pathways regulated neuronal apoptosis and synaptic-axonal remodeling. These findings suggest that treadmill exercise may exhibit a synergistic effect with MSC-exos treatment, which may be related to activation of the JNK1/c-Jun signaling pathway. This study provides novel theoretical evidence for the clinical application of treadmill exercise combined with MSC-exos treatment for ischemic cerebrovascular disease.

11.
J Phys Condens Matter ; 34(50)2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36261040

RESUMEN

The ongoing exploration of the ambiguous boundary between the quantum and the classical worlds has spurred substantial developments in quantum science and technology. Recently, the nonclassicality of dynamical processes has been proposed from a quantum-information-theoretic perspective, in terms of witnessing nonclassical correlations with Hamiltonian ensemble simulations. To acquire insights into the quantum-dynamical mechanism of the process nonclassicality, here we propose to investigate the nonclassicality of the electron spin free-induction-decay process associated with an NV-center. By controlling the nuclear spin precession dynamics via an external magnetic field and nuclear spin polarization, it is possible to manipulate the dynamical behavior of the electron spin, showing a transition between classicality and nonclassicality. We propose an explanation of the classicality-nonclassicality transition in terms of the nuclear spin precession axis orientation and dynamics. We have also performed a series of numerical simulations supporting our findings. Consequently, we can attribute the nonclassical trait of the electron spin dynamics to the behavior of nuclear spin precession dynamics.

12.
Oxid Med Cell Longev ; 2022: 3589277, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35340214

RESUMEN

The disorder of mitochondrial dynamic equilibrium of lung epithelial cell is one of the critical causes of acute lung injury (ALI). Kinsenoside (Kin) serves as an active small-molecule component derived from traditional medicinal herb displaying multiple pharmacological actions in cancers, hyperglycemia, and liver disease. The objective of this study was to investigate the effects of Kin on lipopolysaccharide- (LPS-) induced ALI and further explore possible molecular mechanisms. Kin was administered orally (100 mg/kg/day) for 7 consecutive days before LPS instillation (5 mg/kg). After 12 hours, pathological injury, inflammatory response, and oxidative stress were detected. The results demonstrated that Kin significantly alleviated lung pathological injury and decreased the infiltration of inflammatory cells and the release of inflammatory mediators in bronchoalveolar lavage fluid (BALF), apart from inhibiting the production of reactive oxygen species (ROS) and lipid peroxidation. Meanwhile, Kin also promoted mitochondrial fusion and restrained mitochondrial fission in mice with ALI. In terms of mechanism, Kin pretreatment increased the phosphorylation of AMP-activated protein kinase (AMPK) and the protein level of nuclear factor erythroid 2-related factor 2 (NRF2). In Ampk-α knockout mice challenged with LPS, Kin lost its pulmonary protective effects, accompanied by lower NRF2 level. In vitro experiments further unveiled that either AMPK inhibition by Compound C or NRF2 knockdown by siRNA abolished the protective roles of Kin in LPS-treated A549 lung epithelial cells. And NRF2 activator TAT-14 could reverse the effects of Ampk-α deficiency. In conclusion, Kin possesses the ability to prevent LPS-induced ALI by modulating mitochondrial dynamic equilibrium in lung epithelial cell in an AMPK/NRF2-dependent manner.


Asunto(s)
Lesión Pulmonar Aguda , Lipopolisacáridos , 4-Butirolactona/análogos & derivados , Proteínas Quinasas Activadas por AMP/metabolismo , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/tratamiento farmacológico , Lesión Pulmonar Aguda/metabolismo , Animales , Células Epiteliales/metabolismo , Lipopolisacáridos/farmacología , Pulmón/patología , Ratones , Monosacáridos , Factor 2 Relacionado con NF-E2/metabolismo
13.
World J Clin Cases ; 10(5): 1592-1597, 2022 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-35211597

RESUMEN

BACKGROUND: Unroofed coronary sinus syndrome (UCSS) is a rare congenital heart disease, which has variable morphologic features and is strongly associated with persistent left superior vena cava (PLSVC). However, it is often difficult to visualize the left-to-right shunt pathway through the CS by transthoracic echocardiography (TTE). CASE SUMMARY: A 37-year-old female was admitted to the hepatological surgery department of a hospital with complaint of subxiphoid pain that had started 1 wk prior. Physical examination revealed a grade 3/6 systolic murmur at the left margin of the sternum, between the 2nd and 3rd intercostal cartilage. The patient underwent echocardiography and was diagnosed with ostium primum atrial septal defect (ASD); thus, she was subsequently transferred to the cardiovascular surgery department. A second TTE evaluation before surgery showed type IV UCSS with secundum ASD. Right-heart contrast echocardiography (RHCE) showed that the right atrium and right ventricle were immediately filled with microbubbles, but no microbubble was observed in the CS. Meanwhile, negative filling was observed at the right atrium orifice of the CS and right atrium side of the secundum atrial septal. RHCE identified UCSS combined with secundum ASD but without PLSVC in this patient. CONCLUSION: This rare case of UCSS highlights the value of TTE combined with RHCE in confirming UCSS with ASD or PLSVC.

14.
Sci Rep ; 12(1): 2869, 2022 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-35190613

RESUMEN

It is commonly known that the dephasing in open quantum systems is due to the establishment of bipartite correlations with ambient environments, which are typically difficult to be fully characterized. Recently, a new approach of average over disordered Hamiltonian ensemble is developed and shown to be capable of describing the nonclassicality of incoherent dynamics based on inferring the nonclassical nature of the correlations. Here we further extend the approach of Hamiltonian ensemble in the canonical form to the realm of structural disorder. Under the variable separation of the probability distribution within the Hamiltonian ensemble, the geometrical structure is easily visualized and can be characterized according to the degree of symmetry. We demonstrate four degrees and investigate the effects of different types of symmetry breaking on the incoherent dynamics. We show that these effects are easily understood from the emergences of additional terms in the master equations, leading to rather general master equations and, consequently, going beyond the previous frameworks of pure dephasing or isotropic depolarization.

15.
Curr Med Sci ; 42(1): 48-55, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35089495

RESUMEN

OBJECTIVE: The nuclear factor erythroid 2 (NFE2)-related factor 2 (Nrf2) is associated with doxorubicin (DOX)-induced cardiac injury. It has been reported that microRNA-24-3p (miR-24-3p) may regulate the Keapl by mRNA degradation, whereas Keapl can suppress the activation of Nrf2. However, the role of miR-24-3p in DOX-related cardiotoxicity remains unclear. METHODS: The mice receiving DOX were used as cardiac injury model. In this study, an adenoassociated virus 9 system was used to deliver miR-24-3p or miR-scramble to mice hearts. The echocardiographic and hemodynamic analyses were used to evaluate the effects of miR-24-3p on cardiac function under DOX stimulation. ELISA and RT-PCR were used to detect protein or mRNA expressions associated with cardiac injury, inflammation response, apoptosis and oxidative stress. Western Blot were used for quantitative analysis of the roles of miR-24-3p in regulating Nrf2 expression. H9C2 cells used to verify the role of miR-24-3p in vitro. RESULTS: We found that miR-24-3p mRNA was significantly decreased in DOX-treated mice and cardiomyocytes. Overexpression of miR-24-3p blocked cardiac injury caused by DOX injection, as reflected by the reduction in the levels of cardiac troponin I, creatinine kinase isoenzyme MB and the N-terminal pro brain natriuretic peptide. Furthermore, miR-24-3p reduced oxidative stress and cell loss without affecting the inflammation response. As expected, we found that Nrf2 was upregulated by miR-24-3p supplementation, and that the protective efforts of miR-24-3p supplementation were abolished when Nrf2 was silenced. CONCLUSION: The results from this study suggest that miR-24-3p protects cardiomyocytes against DOX-induced heart injury via activation of the Nrf2 pathway. miR-24-3p supplementation may be a novel strategy to counteract the cardiac side effects of DOX treatment.


Asunto(s)
Antibióticos Antineoplásicos/farmacología , Doxorrubicina/farmacología , Lesiones Cardíacas/inducido químicamente , Lesiones Cardíacas/tratamiento farmacológico , MicroARNs/farmacología , Miocitos Cardíacos/efectos de los fármacos , Factor 2 Relacionado con NF-E2/efectos de los fármacos , Animales , Cardiotoxicidad/tratamiento farmacológico , Ratones , MicroARNs/administración & dosificación
16.
Phys Rev Lett ; 128(2): 027701, 2022 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-35089765

RESUMEN

Integrating the Kondo correlation and spin-orbit interactions, each of which have individually offered unprecedented means to manipulate electron spins, in a controllable way can open up new possibilities for spintronics. We demonstrate electrical control of the Kondo correlation by coupling the bound spin to leads with tunable Rashba spin-orbit interactions, realized in semiconductor quantum point contacts. We observe a transition from single to double peak zero-bias anomalies in nonequilibrium transport-the manifestation of the Kondo effect-indicating a controlled Kondo spin reversal using only spin-orbit interactions. Universal scaling of the Kondo conductance is demonstrated, implying that the spin-orbit interactions could enhance the Kondo temperature. A theoretical model based on quantum master equations is also developed to calculate the nonequilibrium quantum transport.

17.
Comput Math Methods Med ; 2021: 6636396, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34691239

RESUMEN

Group testing (or pool testing), for example, Dorfman's method or grid method, has been validated for COVID-19 RT-PCR tests and implemented widely by most laboratories in many countries. These methods take advantages since they reduce resources, time, and overall costs required for a large number of samples. However, these methods could have more false negative cases and lower sensitivity. In order to maintain both accuracy and efficiency for different prevalence, we provide a novel pooling strategy based on the grid method with an extra pool set and an optimized rule inspired by the idea of error-correcting codes. The mathematical analysis shows that (i) the proposed method has the best sensitivity among all the methods we compared, if the false negative rate (FNR) of an individual test is in the range [1%, 20%] and the FNR of a pool test is closed to that of an individual test, and (ii) the proposed method is efficient when the prevalence is below 10%. Numerical simulations are also performed to confirm the theoretical derivations. In summary, the proposed method is shown to be felicitous under the above conditions in the epidemic.


Asunto(s)
Prueba de COVID-19/métodos , Prueba de COVID-19/normas , COVID-19/diagnóstico , Algoritmos , Simulación por Computador , Reacciones Falso Negativas , Humanos , Laboratorios/normas , Modelos Teóricos , Prevalencia , Probabilidad , Reproducibilidad de los Resultados
19.
Sci Rep ; 11(1): 18532, 2021 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-34535743

RESUMEN

Leydig cells in the testes produce testosterone in the presence of gonadotropins. Therefore, male testosterone levels must oscillate within a healthy spectrum, given that elevated testosterone levels augment the risk of cardiovascular disorders. We observed that the expression of death-associated protein-like 1 (DAPL1), which is involved in the early stages of epithelial differentiation and apoptosis, is considerably higher in the testes of sexually mature mice than in other tissues. Accordingly, Dapl1-null mice were constructed to evaluate this variation. Notably, in these mice, the testicular levels of steroidogenic acute regulatory protein (StAR) and serum testosterone levels were significantly elevated on postnatal day 49. The findings were confirmed in vitro using I-10 mouse testis-derived tumor cells. The in vivo and in vitro data revealed the DAPL1-regulated the expression of StAR involving altered transcription of critical proteins in the protein kinase A and CREB/CREM pathways in Leydig cells. The collective findings implicate DAPL1 as an important factor for steroidogenesis regulation, and DAPL1 deregulation may be related to high endogenous levels of testosterone.


Asunto(s)
Células Intersticiales del Testículo/metabolismo , Testosterona/metabolismo , Animales , Línea Celular , Eliminación de Gen , Masculino , Ratones , Ratones Endogámicos C57BL , Testículo/metabolismo
20.
World J Clin Cases ; 9(24): 7085-7091, 2021 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-34540963

RESUMEN

BACKGROUND: Lymphangioleiomyomatosis (LAM) is a rare cystic lung disease characterized by the proliferation, metastasis, and infiltration of smooth muscle cells in the lung and other tissues, which can be associated with tuberous sclerosis complex (TSC). The disorder of TSC has a variable expression, and there is great phenotypic variability. CASE SUMMARY: A 32-year-old Chinese woman with a history of multiple renal angioleiomyolipoma presented with a productive cough persisting for over 2 wk. High-resolution chest computed tomography revealed interstitial changes, multiple pulmonary bullae, bilateral pulmonary nodules, and multiple fat density areas of the inferior mediastinum. Conventional and contrast ultrasonography revealed multiple high echogenic masses of the liver, kidneys, retroperitoneum, and inferior mediastinum. These masses were diagnosed as angiomyolipomas. Pathology through thoracoscopic lung biopsy confirmed LAM. Furthermore, high-throughput genome sequencing of peripheral blood DNA confirmed the presence of a heterozygous mutation, c.1831C>T (p.Arg611Trp), of the TSC2 gene. The patient was diagnosed with TSC-LAM. CONCLUSION: We highlight a rare case of TSC-LAM and the first report of a mediastinum lymphangioleiomyoma associated with TSC-LAM.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...