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Alcohols carbonylation is of great importance in industry but remains a challenge to abandon the usage of the halide additives and noble metals. Here we report the realization of direct alcohols heterogeneous carbonylation to carbonyl-containing chemicals, especially in methanol carbonylation, with a remarkable space-time-yield (STY) of 4.74 molacetyl/kgcat./h and a durable stability as long as 100 h on Ni@MoS2 catalyst. Mechanistic analysis reveals that the Mo-Ni dual sites localized at edge sulfur vacancies of Ni@MoS2 exhibit distinct charge density, which strongly activate CH3OH to break its C-O bond and non-dissociatively activate CO. Density functional theory calculations further suggest that the low charge density in Mo-Ni, the Ni site, could significantly lower the barrier for CO migration and nucleophilic attack of methoxy species, and finally leads to the rapid formation of acetyl products. Ni@MoS2 catalyst could also effectively realize the carbonylation of ethanol, n-propanol and n-butanol to their acyl products, which may demonstrate its universal application for alcohols carbonylation.
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Intrinsic and extrinsic aging affect the health of human skin. Extracellular matrix protein degradation, DNA damage and oxidative stress are known to disturb skin architecture and skin homeostasis leading to skin aging. Traditional Chinese Medicine (TCM) delivers a large amount of knowledge regarding the phytotherapeutic power of diverse plants. Panax ginseng, Polygonatum cyrtonema, Epiphyllum oxypetalum, Nelumbo nucifera and Osmanthus fragrans are five plants used in TCM for their protective effect. In this study, several combinations of these TCM plants were explored: first, an in silico analysis was performed to predict their potential to target biological activities in the skin and then, some predictions were verified with in vitro studies to underline the synergistic effect of plant extracts. The results showed a stronger anti-aging activity for the combination with the five plants compared to the combination with Panax ginseng, Polygonatum cyrtonema, Epiphyllum oxypetalum and, compared to Panax ginseng alone.
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Alginate oligosaccharides (AOS), extracted from marine brown algae, are a common functional feed additive; however, it remains unclear whether they modulate the gut microbiota and microbial metabolites. The response of Salmonella enterica serovar Typhimurium, a common poultry pathogen, to AOS fermented with chicken fecal inocula was investigated using metabolomic and transcriptomic analyses. Single-strain cultivation tests showed that AOS did not directly inhibit the growth of S. Typhimurium. However, when AOS were fermented by chicken fecal microbiota, the supernatant of fermented AOS (F-AOS) exhibited remarkable antibacterial activity against S. Typhimurium, decreasing the abundance ratio of S. Typhimurium in the fecal microbiota from 18.94 to 2.94%. Transcriptomic analyses showed that the 855 differentially expressed genes induced by F-AOS were mainly enriched in porphyrin and chlorophyll metabolism, oxidative phosphorylation, and Salmonella infection-related pathways. RT-qPCR confirmed that F-AOS downregulated key genes involved in flagellar assembly and the type III secretory system of S. Typhimurium, indicating metabolites in F-AOS can influence the growth and metabolism of S. Typhimurium. Metabolomic analyses showed that 205 microbial metabolites were significantly altered in F-AOS. Among them, the increase in indolelactic acid and 3-indolepropionic acid levels were further confirmed using HPLC. This study provides a new perspective for the application of AOS as a feed additive against pathogenic intestinal bacteria. Supplementary Information: The online version contains supplementary material available at 10.1007/s42995-023-00176-z.
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Objective: To investigate the value of the retinal nerve fiber layer (RNFL) thickness in the optic disc and the cross-sectional area (CSA) of lower limb nerves in the diagnosis of diabetic peripheral neuropathy (DPN) separately and in combination. Methods: A total of 140 patients with type 2 diabetes were enrolled, including 51 patients with DPN (DPN group) and 89 patients without DPN (NDPN group). Clinical data and biochemical parameters were collected. Electromyography/evoked potential instrument was performed for nerve conduction study. Optical coherence tomography was performed to measure the RNFL thickness of the optic disc. Color Doppler ultrasound was performed to measure CSA of lower limb nerves. Results: The RNFL thickness was lower and the CSA of the tibial nerve (TN) in the DPN group was larger than that in the NDPN group. The album/urine creatinine ratio, diabetic retinopathy, and CSA of TN at 3 cm were positively correlated with DPN. The RNFL thickness in the superior quadrant of the optic disc was negatively correlated with DPN. For RNFL thickness to diagnose DPN, the area under the curve (AUC) of the superior quadrant was the largest, which was 0.723 (95% confidence interval [CI]: 0.645-0.805), and the best cutoff value was 127.5 µm (70.5% sensitivity, 72.1% specificity). For CSA of TN to diagnose DPN, the AUC of the distance of 5 cm was the largest, which was 0.660 (95% CI: 0.575-0.739), and the best cutoff value was 13.50 mm2 (82.0% sensitivity, 41.6% specificity). For the combined index, the AUC was greater than that of the above two indicators, which was 0.755 (95% CI: 0.664-0.846), and the best cutoff value was 0.376 (64.3% sensitivity, 83.0% specificity). Conclusions: Patients with DPN have a reduction of the RNFL thickness and an increase in the CSA of TN, and these two changes are related to DPN. The RNFL thickness of the optic disc and the CSA of TN can be used as diagnostic indicators of DPN, and the combination of the two indicators has a higher diagnostic value.
Asunto(s)
Diabetes Mellitus Tipo 2 , Neuropatías Diabéticas , Humanos , Diabetes Mellitus Tipo 2/complicaciones , Neuropatías Diabéticas/diagnóstico por imagen , Fibras Nerviosas , Retina , Células Ganglionares de la Retina , Nervio Tibial , Tomografía de Coherencia Óptica/métodos , Ultrasonografía Doppler en ColorRESUMEN
Egg-shell, egg-yolk and egg-white types of Co/SiO2 catalysts were prepared by utilizing entrapped air to inhibit the entrance of impregnation or leaching solution into the cores of catalyst pellets during the preparation procedure; the entrapped air played the important role because the capillary pressure was reduced to a suitable range by adjusting the concentration of ethanol in the impregnation or leaching solution for a hydrophobized silica surface.