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1.
Sci Total Environ ; 937: 173381, 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-38782274

RESUMEN

The chemical weathering process of carbonate rocks consumes a large quantity of CO2. This has great potential as a carbon sink, and it is one of a significant pathway for achieving carbon neutrality. However, the control mechanisms of karst carbon sink fluxes are unclear, and there is a lack of effective and accurate accounting. We took the Puding Shawan karst water­carbon cycle test site in China, which has identical initial conditions but different land use types, as the research subject. We used controlled experiments over six years to evaluate the mechanisms for the differences in hydrology, water chemistry, concentrations and fluxes of dissolved organic carbon (DOC) and dissolved inorganic carbon (DIC). We found that the transition from rock to bare soil to grassland led to increases in the DIC concentration by 0.08-0.62 mmol⋅L-1. The inorganic carbon sink flux (CSF) increased by 3.01-5.26 t⋅C⋅km-2⋅a-1, an increase amplitude of 30-70 %. The flux of dissolved organic carbon (FDOC) increase by 0.28 to 0.52 t⋅C⋅km-2⋅a-1, an increase amplitude of 34-90 %. We also assessed the contribution of land use modifications to regional carbon neutrality, it indicate that positive land use modification can significantly regulate the karst carbon sink, with grassland having the greatest carbon sequestration ability. Moreover, in addition to DOC from soil organic matter degradation, DOC production by chemoautotrophic microorganisms utilizing DIC in groundwater may also be a potential source. Thus, coupled studies of the conversion of DIC to DOC processes in groundwater are an important step in assessing karst carbon sink fluxes.

2.
Gels ; 10(4)2024 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-38667638

RESUMEN

Bacterial infections impede the wound healing process and can trigger local or systemic inflammatory responses. Therefore, there is an urgent need to develop a dressing with antimicrobial and anti-inflammatory properties to promote the healing of infected wounds. In this study, BA/COs/NO-PL/AL hydrogels were obtained by adding brevilin A (BA) camellia oil (CO) submicron emulsion and nitric oxide (NO) to hydrogels consisting of sodium alginate (AL) and Pluronic F127 (PL). The hydrogels were characterized through dynamic viscosity analysis, differential scanning calorimetry, and rheology. They were evaluated through anti-inflammatory, antimicrobial, and wound healing property analyses. The results showed that BA/COs/NO-PL/AL hydrogels were thermo-responsive and had good ex vivo and in vivo anti-inflammatory activity, and they also exhibited strong antimicrobial activity against methicillin-resistant Staphylococcus aureus Pseudomonas aeruginosa (MRPA) and methicillin-resistant Staphylococcus aureus (MRSA). They were able to effectively promote healing of the infected wound model and reduce inflammation and bacterial burden. H&E and Masson's staining showed that BA/COs/NO-PL/AL hydrogels promoted normal epithelial formation and collagen deposition. In conclusion, BA/COs/NO-PL/AL hydrogels are promising candidates for promoting the healing of infected wounds.

3.
IEEE Trans Med Imaging ; 43(2): 886-898, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37847618

RESUMEN

The neuron reconstruction from raw Optical Microscopy (OM) image stacks is the basis of neuroscience. Manual annotation and semi-automatic neuron tracing algorithms are time-consuming and inefficient. Existing deep learning neuron reconstruction methods, although demonstrating exemplary performance, greatly demand complex rule-based components. Therefore, a crucial challenge is designing an end-to-end neuron reconstruction method that makes the overall framework simpler and model training easier. We propose a Neuron Reconstruction Transformer (NRTR) that, discarding the complex rule-based components, views neuron reconstruction as a direct set-prediction problem. To the best of our knowledge, NRTR is the first image-to-set deep learning model for end-to-end neuron reconstruction. The overall pipeline consists of the CNN backbone, Transformer encoder-decoder, and connectivity construction module. NRTR generates a point set representing neuron morphological characteristics for raw neuron images. The relationships among the points are established through connectivity construction. The point set is saved as a standard SWC file. In experiments using the BigNeuron and VISoR-40 datasets, NRTR achieves excellent neuron reconstruction results for comprehensive benchmarks and outperforms competitive baselines. Results of extensive experiments indicate that NRTR is effective at showing that neuron reconstruction is viewed as a set-prediction problem, which makes end-to-end model training available.


Asunto(s)
Encéfalo , Microscopía , Neuronas , Algoritmos , Imagenología Tridimensional/métodos , Procesamiento de Imagen Asistido por Computador
4.
Neuroradiology ; 65(1): 55-64, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35835879

RESUMEN

PURPOSE: To evaluate two advanced diffusion models, diffusion kurtosis imaging and the newly proposed mean apparent propagation factor-magnetic resonance imaging, in the grading of gliomas and the assessing of their proliferative activity. METHODS: Fifty-nine patients with clinically diagnosed and pathologically proven gliomas were enrolled in this retrospective study. All patients underwent DKI and MAP-MRI scans. Manually outline the ROI of the tumour parenchyma. After delineation, the imaging parameters were extracted using only the data from within the ROI including mean diffusion kurtosis (MK), return-to-origin probability (RTOP), Q-space inverse variance (QIV) and non-Gaussian index (NG), and the differences in each parameter in the classification of glioma were compared. Receiver operating characteristic (ROC) curve analysis was used to evaluate the diagnostic performance of these parameters. RESULTS: MK, NG, RTOP and QIV were significantly different amongst the different grades of glioma. MK, NG and RTOP had excellent diagnostic value in differentiating high-grade from low-grade glioma, with largest areas under the curve (AUCs; 0.929, 0.933 and 0.819, respectively; P < 0.01). MK and NG had the largest AUCs (0.912 and 0.904) when differentiating grade II tumours from III tumours (P < 0.01) and large AUCs (0.791 and 0.786) when differentiating grade III from grade IV tumours. Correlation analysis of tumour proliferation activity showed that MK, NG and QIV were strongly correlated with the Ki-67 LI (P < 0.001). CONCLUSION: MK, RTOP and NG can effectively represent the microstructure of these altered tumours. Multimodal diffusion-weighted imaging is valuable for the preoperative evaluation of glioma grade and tumour proliferative activity.


Asunto(s)
Neoplasias Encefálicas , Glioma , Humanos , Estudios Retrospectivos , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/patología , Sensibilidad y Especificidad , Clasificación del Tumor , Glioma/diagnóstico por imagen , Glioma/patología , Imagen de Difusión por Resonancia Magnética/métodos , Imagen por Resonancia Magnética , Proliferación Celular
5.
Front Immunol ; 13: 1008072, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36325336

RESUMEN

Interferons (IFNs) bind to cell surface receptors and activate the expression of interferon-stimulated genes (ISGs) through intracellular signaling cascades. ISGs and their expression products have various biological functions, such as antiviral and immunomodulatory effects, and are essential effector molecules for IFN function. ISGs limit the invasion and replication of the virus in a cell-specific and region-specific manner in the central nervous system (CNS). In addition to participating in natural immunity against viral infections, studies have shown that ISGs are essential in the pathogenesis of CNS disorders such as neuroinflammation and neurodegenerative diseases. The aim of this review is to present a macroscopic overview of the characteristics of ISGs that restrict viral neural invasion and the expression of the ISGs underlying viral infection of CNS cells. Furthermore, we elucidate the characteristics of ISGs expression in neurological inflammation, neuropsychiatric disorders such as depression as well as neurodegenerative disorders, including Alzheimer's disease (AD), Parkinson's disease (PD), and amyotrophic lateral sclerosis (ALS). Finally, we summarize several ISGs (ISG15, IFIT2, IFITM3) that have been studied more in recent years for their antiviral infection in the CNS and their research progress in neurological diseases.


Asunto(s)
Interferones , Virosis , Humanos , Interferones/metabolismo , Antivirales , Virosis/genética , Inmunidad Innata , Sistema Nervioso Central/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas de Unión al ARN
6.
Front Neurosci ; 16: 981772, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36440294

RESUMEN

Spinal cord injury (SCI) is a central nervous system (CNS) disease that can cause sensory and motor impairment below the level of injury. Currently, the treatment scheme for SCI mainly focuses on secondary injury and complications. Recent studies have shown that SCI leads to an imbalance of intestinal microbiota and the imbalance is also associated with complications after SCI, possibly through the microbial-brain-gut axis. Melatonin is secreted in many parts of the body including pineal gland and gut, effectively protecting the spinal cord from secondary damage. The secretion of melatonin is affected by circadian rhythms, known as the dark light cycle, and SCI would also cause dysregulation of melatonin secretion. In addition, melatonin is closely related to the intestinal microbiota, which protects the barrier function of the gut through its antioxidant and anti-inflammatory effects, and increases the abundance of intestinal microbiota by influencing the metabolism of the intestinal microbiota. Furthermore, the intestinal microbiota can influence melatonin formation by regulating tryptophan and serotonin metabolism. This paper summarizes and reviews the knowledge on the relationship among intestinal microbiota, melatonin, and SCI in recent years, to provide new theories and ideas for clinical research related to SCI treatment.

7.
Opt Express ; 30(10): 16794-16801, 2022 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-36221514

RESUMEN

Room-temperature polariton lasing is achieved in GaN microrods grown by metal-organic vapor phase epitaxy. We demonstrate a large Rabi splitting (Ω = 2g0) up to 162 meV, exceeding the results from both the state-of-the-art nitride-based planar microcavities and previously reported GaN microrods. An ultra-low threshold of 1.8 kW/cm2 is observed by power-dependent photoluminescence spectra, with the linewidth down to 1.31 meV and the blue shift up to 17.8 meV. This large Rabi splitting distinguishes our coherent light emission from a conventional photon lasing, which strongly supports the preparation of coherent light sources in integrated optical circuits and the study of exciting phenomena in macroscopic quantum states.

8.
Opt Express ; 30(3): 3973-3988, 2022 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-35209645

RESUMEN

The electrical-to-optical power conversion efficiencies of the light-emitting devices based on gallium nitride (GaN) are seriously limited by electron leakage currents due to the relatively low mobility and activation ratio of holes. However, there have been few theoretical models on the behavior of the leakage current with an increasing total current. We develop an Ohmic-law-like method to describe the transport behaviors of the systems with electron and hole currents simultaneously. Based on reasonable assumptions, the ratio of the leakage current to the total current is related to the differential resistances of the devices. Through the method, we develop analytical models of the leakage currents in GaN-based laser diodes (LDs) and light-emitting diodes (LEDs). The ratios of the leakage currents with total currents in LDs and LEDs are shown to increase, which explains the sublinear behaviors of the luminescence-current (LI) curves of the devices. The theory agrees well with the numerical simulation and experimental results in larger current ranges in comparison to the traditional ABC model. The above analytical model can be used to fast evaluate the leakage currents in GaN-based LDs and LEDs.

9.
Biomed Pharmacother ; 145: 112475, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34861636

RESUMEN

BACKGROUND: Jianpi-Qushi-Heluo formula (JQHF) has been used to treat idiopathic membranous nephropathy (IMN) in hospitals for many years. PURPOSE: Elucidating the protective effect and exploring the potential mechanism of JQHF against IMN. METHODS: Passive Heymann nephritis (PHN) was induced in rats by a single tail vein injection of anti-Fx1A antiserum. Then, the animals were treated with JQHF at 16.2 g/kg or 32.4 g/kg, with benzepril (10 mg/kg) as a positive control. Renal function was evaluated by biochemical measurements and pathological testing. Fecal samples were collected before and after treatment to analyze the gut microbiota composition by shotgun whole metagenome sequencing. RESULTS: JQHF exhibited potent efficacy in ameliorating PHN at both doses, as revealed by decreasing the deposition of IgG and C5b-9, relieving podocyte injury, and reducing glomerular and tubular cell apoptosis. The lower dose was corresponding to the clinical dosage and showed better therapeutic effects than the higher dose. Metagenomic analysis showed that gavage with 16.2 g/kg of JQHF shifted the structure of the gut microbiota in PHN rats and significantly increased the relative abundances of Prevotella copri, Lactobacillus vaginalis and Subdoligranulum variabile. Particularly, S. variabile was strongly negatively correlated with serum levels of TC and TG, the deposition of IgG and C5b-9, and apoptosis of glomerular cells. CONCLUSIONS: The JQHF is an effective agent for the treatment of experimental PHN. The PHN-allevating effect of JQHF is associated with specific alternation of gut microbiota.


Asunto(s)
Medicamentos Herbarios Chinos/farmacología , Microbioma Gastrointestinal , Glomerulonefritis Membranosa , Podocitos , Animales , Antioxidantes/farmacología , Apoptosis/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Monitoreo de Drogas , Medicamentos Herbarios Chinos/análisis , Microbioma Gastrointestinal/efectos de los fármacos , Microbioma Gastrointestinal/fisiología , Glomerulonefritis Membranosa/tratamiento farmacológico , Glomerulonefritis Membranosa/metabolismo , Glomerulonefritis Membranosa/microbiología , Estrés Oxidativo/efectos de los fármacos , Podocitos/efectos de los fármacos , Podocitos/metabolismo , Ratas , Resultado del Tratamiento
10.
J Transl Int Med ; 9(3): 161-167, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34900626

RESUMEN

IgA nephropathy (IgAN) is a major cause of chronic kidney disease (CKD) and end-stage renal disease worldwide. Currently, clinical interventions for IgAN are limited, and many patients seek out alternative therapies such as traditional Chinese medicine (TCM). In the last several years, TCM has accumulated ample application experiences and achieved favorable clinical effects. This article summarizes high-quality research from basic science to clinical applications aimed to provide more evidence-based medicine proof for the clinical treatment of IgAN. In summary, qi and yin deficiency accounted for the largest proportion in IgAN patients, and the treatment of IgAN should be based on supplementing qi and nourishing yin. Further, for patients with severe IgAN, the treatment combination of Chinese and Western medicines is better than pure Chinese medicine or hormone therapy. In addition, the pharmacological mechanism of Chinese herbal medicines is mostly based on restoring the immune function, relieving the inflammation damage, and inhibiting proliferation of the glomerular mesangial cells.

11.
Medicine (Baltimore) ; 100(41): e27541, 2021 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-34731154

RESUMEN

ABSTRACT: Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder that affects specific groups of people. The relationship between breakfast consumption frequency and the risk of IBS is unclear. This study aimed to investigate the association between breakfast consumption frequency and the risk of IBS among Chinese female college students.In this cross-sectional study (n = 706) conducted in October 2018, the frequency of breakfast consumption was categorized as 0 to 3 times/week, 4 to 6 times/week, or daily. IBS was diagnosed according to the Rome III criteria and was based on the presence of abdominal pain or discomfort for at least 3 months during the previous 6 months, with at least 2 or more of the following conditions: changes in frequency or form of stool and/or decrease in pain after defecation. We adjusted for confounding factors, including age, only child (yes or no), parents' educational levels (senior high school or below, college, or postgraduate), parents' marital status (married, widowed, or divorced), smoking status (smoker or nonsmoker), drinking status (drinker or nondrinker), body mass index, and depressive symptoms. A multiple logistic regression analysis was performed to determine the relationship between breakfast frequency and the risk of IBS.Among 706 participants, 23.7% were the only child in their family, and the proportion of parents divorced or widowed was 18.5%. The proportion of fathers and mothers with high school education or above was 93.3% and 96.3%, respectively. The prevalence of IBS among the participants was 17.3% (122/706). Multivariate logistic regressions analysis showed that breakfast consumption frequency is negatively associated with the risk of IBS after adjusting for confounding factors. The odds ratios (95% confidence intervals) for IBS in the breakfast frequency category of 0 to 3 times/week, 4 to 6 times/week, and daily were 1.00 (reference), 0.96 (0.58, 1.60), and 0.45 (0.26, 0.78), respectively (P = .002).Our data revealed that regular breakfast consumption is associated with a lower risk of IBS among Chinese college students. Future cohort and/or interventional studies should be conducted to further explore the association between breakfast consumption frequency and IBS.


Asunto(s)
Dolor Abdominal/diagnóstico , Desayuno/etnología , Economía/tendencias , Enfermedades Gastrointestinales/fisiopatología , Síndrome del Colon Irritable/epidemiología , Dolor Abdominal/etiología , Adolescente , Pueblo Asiatico/etnología , Índice de Masa Corporal , Estudios Transversales , Depresión/epidemiología , Ingestión de Líquidos , Escolaridad , Femenino , Humanos , Síndrome del Colon Irritable/diagnóstico , Estado Civil , Padres , Prevalencia , Factores de Riesgo , Fumar/epidemiología , Estudiantes , Universidades/estadística & datos numéricos , Adulto Joven
12.
Opt Express ; 29(24): 39788-39800, 2021 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-34809335

RESUMEN

We investigate the exciton polaritons and their corresponding optical modes in a hexagonal GaN microrod at room temperature. The dispersion curves are measured by the angle-resolved micro-photoluminescence spectrometer, and two types of exciton polaritons are identified with the help of the finite-difference time-domain simulation. By changing the pump position, the photon part of the exciton polaritons is found to switch between the quasi-whispering gallery modes and the two-round quasi-whispering gallery modes. The exciton polaritons formed by the latter are observed and distinguished for the first time, with a giant Rabi splitting as large as 2Ω = 230.3 meV.

13.
Front Pharmacol ; 12: 730681, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34475825

RESUMEN

Background: Administration of aspirin has the potential for significant side effects of gastrointestinal (GI) injury mainly caused by gastric acid stimulation, especially in long-term users or users with original gastrointestinal diseases. The debate on the optimal treatment of aspirin-induced gastrointestinal injury is ongoing. We aimed to compare and rank the different treatments for aspirin-induced gastrointestinal injury based on current evidence. Methods: We searched PubMed, EMBASE, Cochrane Library (Cochrane Central Register of Controlled Trials), and Chinese databases for published randomized controlled trials (RCTs) of different treatments for aspirin-induced gastrointestinal injury from inception to 1 May 2021. All of the direct and indirect evidence included was rated by network meta-analysis under a Bayesian framework. Results: A total of 10 RCTs, which comprised 503 participants, were included in the analysis. The overall quality of evidence was rated as moderate to high. Eleven different treatments, including omeprazole, lansoprazole, rabeprazole, famotidine, geranylgeranylacetone, misoprostol, ranitidine bismuth citrate, chili, phosphatidylcholine complex, omeprazole plus rebamipide, and placebo, were evaluated in terms of preventing gastrointestinal injury. It was suggested that omeprazole plus rebamipide outperformed other treatments, whereas geranylgeranylacetone and placebo were among the least treatments. Conclusion: This is the first systematic review and network meta-analysis of different treatments for aspirin-induced gastrointestinal injury. Our study suggested that omeprazole plus rebamipide might be considered the best option to treat aspirin-induced gastrointestinal injury. More multicenter, high quality, large sample size randomized controlled trials will confirm the advantages of these medicines in the treatment of aspirin-induced gastrointestinal injury in the future.

14.
Sci Rep ; 11(1): 18338, 2021 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-34526554

RESUMEN

Jianpi Qushi Heluo Formula (JQHF) is an empirical traditional Chinese medicine prescription for treating Membranous Nephropathy (MN) clinically in China. The therapeutic effect of JQHF has been reported in our previous studies. However, the exact mechanism is still unknown. In this study, by establishing an experimental rat model of MN induced by Sheep anti-rat Fx1A serum, we evaluated the effects of JQHF and Tetrandrine (TET), and Benazepril was used as a positive control. As an autophagy agonist, TET is one of the most active components in JQHF. After 4 weeks, significant kidney damage was observed in the rats in the Model group; comparatively, JQHF markedly decreased 24 h urinary protein, Total Cholesterol (TC), and increased serum total Albumin (ALB). Histology showed that JQHF caused significant improvements in glomerular hyperplasia, renal tubular damage, IgG immune complex deposition, and the ultrastructure of mitochondria in MN rats. Flow cytometry analysis showed that treatment with JQHF reduced the level of reactive oxygen species and apoptosis rate, and upregulated mitochondrial membrane potential. Western blot analysis demonstrated that JQHF could protect against mitochondrial dysfunction and apoptosis by upregulating the expression of PINK1, Mitochondrial Parkin, and LC3-II/I, downregulating the expression of Cytoplasmic Parkin, P62, Cytochrome c, and Caspase-3 in the kidneys of MN rats. From images of co-immunofluorescence, it is observed significantly increase in the co-localization of PINK1 and Parkin, as well as LC3 and mitochondria. Similarly, TET treatment significantly upregulated the mitochondrial autophagy and reduced apoptosis in rats after 4 weeks compared with the model group. Comparatively, the ability of JQHF to alleviate renal damage was significantly higher than those of Benazepril and TET. It was demonstrated that JQHF could delay pathology damage to the kidney and hold back from the progression of MN by inhibiting apoptosis and upregulating the mitochondrial autophagy by PINK1/Parkin pathways.


Asunto(s)
Antiinflamatorios/uso terapéutico , Medicamentos Herbarios Chinos/uso terapéutico , Glomerulonefritis Membranosa/tratamiento farmacológico , Riñón/efectos de los fármacos , Mitofagia , Ubiquitina-Proteína Ligasas/metabolismo , Animales , Antiinflamatorios/farmacología , Apoptosis , Medicamentos Herbarios Chinos/farmacología , Riñón/metabolismo , Potencial de la Membrana Mitocondrial , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Mitocondrias/ultraestructura , Estrés Oxidativo , Proteínas Quinasas/metabolismo , Ratas , Ratas Sprague-Dawley
15.
Artículo en Inglés | MEDLINE | ID: mdl-34335822

RESUMEN

BACKGROUND: Aspirin is the first-line medication for prevention and treatment of coronary heart disease (CHD). However, long-term use of aspirin resulting in gastrointestinal mucosal injury and bleeding limits the regularity of medication. Xuesaitong is a marketed Chinese medicine contained main active component in Panax notoginseng saponins (PNS), which can significantly inhibit platelet aggregation in patients with CHD. Our previous studies have already showed that PNS could reduce the gastrointestinal mucosal injury caused by aspirin in preclinical study. However, there is a need for further clinical studies to evaluate synergy and attenuation effect of the combination. METHODS: This trial is a prospectively planned, open-labeled, parallel-grouped, single-centered clinical trial. A total of eligible 480 participants will be randomly allocated into three groups: aspirin group, Xuesaitong group, and drug combination group at a ratio of 1 : 1 : 1. The primary outcome is the change of platelet aggregation rate and calprotectin activity. Secondary outcomes include PAC-1, P-selectin, P2Y12, I-FABP activity, and fecal occult blood. Discussion. The results of the study are expected to provide evidence of high methodological and reporting quality on the synergy function of Xuesaitong and aspirin upon the antiplatelet and anti-gastrointestinal injury effect for CHD. It also provides an experimental basis for clinical rational drug combination therapy. Trial Registration. This trial was registered in the Chinese Clinical Trail Registry, ChiCTR2000036311, on 22 August 2020, http://www.chictr.org.cn/edit.aspx?pid=58798&htm=4.

16.
Chem Asian J ; 16(18): 2622-2625, 2021 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-34403212

RESUMEN

Single-atom catalysis has become a new branch in heterogeneous catalysis. Although the naturally produced SiO2 -based materials are abundant and stable, fabrication of single-atom catalysts on such supports with high loading remains as a formidable challenge due to the lack of bonding sites to anchor the isolated metal species. Herein, modifying the diatomite, a kind of pure SiO2 mineral, with CeO2 nanoparticles is demonstrated to increase the defect sites on the support. The enhanced metal-support interaction maintains the atomic dispersion of Pt species with above 1 wt.% loading, exhibiting good performance in the selective hydrogenation of phenylacetylene to styrene.

17.
Chem Rev ; 120(21): 11986-12043, 2020 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-33112599

RESUMEN

Metal atoms dispersed on the oxide supports constitute a large category of single-atom catalysts. In this review, oxide supported single-atom catalysts are discussed about their synthetic procedures, characterizations, and reaction mechanism in thermocatalysis, such as water-gas shift reaction, selective oxidation/hydrogenation, and coupling reactions. Some typical oxide materials, including ferric oxide, cerium oxide, titanium dioxide, aluminum oxide, and so on, are intentionally mentioned for the unique roles as supports in anchoring metal atoms and taking part in the catalytic reactions. The interactions between metal atoms and oxide supports are summarized to give a picture on how to stabilize the atomic metal centers, and rationally tune the geometric structures and electronic states of single atoms. Furthermore, several directions in fabricating single-atom catalysts with improved performance are proposed on the basis of state-of-the-art understanding in metal-oxide interactions.

18.
Chronic Dis Transl Med ; 6(2): 124-133, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32596649

RESUMEN

BACKGROUND: The incidence of idiopathic membranous nephropathy (IMN) has recently increased remarkably. Immune dysfunction caused by disordered intestinal flora might be an important factor affecting IMN. The Jian Pi Qu Shi Formula (JPQSF) shows promise in treating IMN. Here, we sequenced 16S rRNA genes to compare intestinal flora between patients with IMN and healthy persons. We also conducted a randomized controlled clinical trial to further compare the intestinal flora of patients with IMN treated with traditional Chinese medicine (TCM) and western medicine (WM). METHODS: Among 40 patients with IMN treated at Department of Nephrology in Xiyuan Hospital, Chinese Academy of Traditional Chinese Medicine between July 2016 and December 2018, we compared 30 of them with 10 healthy persons (controls). The IMN group was randomly assigned to receive JPQSF (TCM) or immunosuppressant WM therapy in (n = 15 per group) for 6 months. Intestinal microbiota diversity was analyzed using alpha diversity and beta diversity. Intestinal flora that significantly differed between the groups was analyzed using MetaStat. The effects and safety of the therapies were determined based on the values for plasma albumin, 24-h urine protein excretion, serum creatinine, urea nitrogen, estimate glomerular filtration rate (eGFR), complete blood count, and liver enzymes. All data were statistically analyzed using Statistical Package for the Social Sciences (SPSS) 20.0 statistical software. RESULTS: Baseline characteristics did not significantly differ between the IMN and healthy groups, or the TCM and WM groups. After six months of treatment, 24-h urinary protein significantly declined in the TCM and WM groups (before and after treatment: 3.24 ± 1.74 vs. 1.73 ± 1.85 g, P < 0.05 and 3.94 ± 1.05 vs. 1.91 ± 1.18 g, P < 0.05, respectively). Plasma albumin was significantly increased in the TCM group (before vs. after treatment: 32.44 ± 9.04 vs. 39.99 ± 7.03 g/L, P < 0.05), but did not significantly change in the WM group (31.55 ± 4.23 vs. 34.83 ± 9.14 g/L, P > 0.05). Values for urea nitrogen, serum creatinine, and eGFR did not significantly change in either group. The alpha diversity index for intestinal flora differed between the IMN and healthy groups, and the TCM and WM groups. Comparisons of multiple samples (beta diversity) revealed differences in intestinal flora between the IMN and healthy groups, and the TCM and WM groups. The Metastat analysis findings showed that the main genera that differed between the IMN group before treatment and the healthy group were Christensenellaceae_R-7_group, Bifidobacterium (77), Dorea, Escherichia-Shigella, Parabacteroides, Bifidobacterium, and Coprococcus_3. After TCM therapy, the main differential genera were Butyricimonas, Bacteroides, Alistipes, and Lachnospira, and after WM therapy, these were Ruminococcus_2, Lachnospiraceae_ND3007_group, Lachnospira, Bifidobacterium, Alistipes, and [Eubacterium]_ventriosum_group. CONCLUSION: Patients with IMN might have disordered intestinal flora, and JPQSF can regulate intestinal flora in patients with IMN.

19.
J Transl Int Med ; 8(1): 3-8, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32435606

RESUMEN

This article reviews the most significant literature of the recent years on the treatment of idiopathic membranous nephropathy (IMN) with traditional Chinese medicine (TCM). One major goal of the article is to classify and summarize the research on the clinical aspects and the associated mechanisms of the use of Chinese herbal compounds and single drugs to treat IMN. It was found that TCM treats IMN via two major approaches: by benefiting qi, activating blood circulation and eliminating dampness, or by benefiting qi and nourishing yin. The method of benefiting qi, to activate blood circulation and eliminate dampness for dredging channels, is the most popular. The commonly used drugs in this approach include Huang Qi (astragalus), Dang Shen (codonopsis root), Bai Zhu (white atractylodes rhizome), Fu Ling (poria cocos), Dang Gui (angelica sinensis), and so on. Several randomized, controlled, clinical trials are reviewed in the article, including a multicenter one.

20.
Angew Chem Int Ed Engl ; 59(19): 7430-7434, 2020 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-32037716

RESUMEN

The hydroformylation of olefins is one of the most important homogeneously catalyzed industrial reactions for aldehyde synthesis. Various ligands can be used to obtain the desired linear aldehydes in the hydroformylation of aliphatic olefins. However, in the hydroformylation of aromatic substrates, branched aldehydes are formed preferentially with common ligands. In this study, a novel approach to selectively obtain linear aldehydes in the hydroformylation of styrene and its derivatives was developed by coupling with a water-gas shift reaction on a Rh single-atom catalyst without the use of ligands. Detailed studies revealed that the hydrogen generated in situ from the water-gas shift is critical for the highly regioselective formation of linear products. The coupling of a traditional homogeneous catalytic process with a heterogeneous catalytic reaction to tune product selectivity may provide a new avenue for the heterogenization of homogenous catalytic processes.

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