ARTICLE | doi:10.20944/preprints202304.0671.v1
Subject: Chemistry And Materials Science, Materials Science And Technology Keywords: Electrospinning; Nanomaterials; Carboxymethyl cellulose; Water purification
Online: 21 April 2023 (05:19:58 CEST)
CMC/PVA composite nanofiber membrane was prepared by electrostatic spinning method, using carboxymethyl cellulose (CMC) and polyvinyl alcohol (PVA) as raw materials and glutaraldehyde as cross-linking agent. The structure, morphology, thermal stability, and filtration performance of CMC/PVA nanofiber membranes were characterized by advanced instrumental analysis methods such as scanning electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, ultraviolet analysis and energy spectrum analysis. The results show that the average fiber diameter decreases from 381 nm to 183 nm, when the spinning voltage is 23 KV and the jet speed is 2 µL/min. The obtained fiber has the smallest particle size and the most uniform distribution. Infrared spectroscopy analysis confirms that the adsorption behavior of nanofiber membranes on Cu2+ and Cr6+ is chemical adsorption. The retention rates of CMC/PVA nanofiber membranes for Cu2+ and Cr6+ reached 97% and 98%, respectively.
ARTICLE | doi:10.20944/preprints202309.1997.v1
Subject: Medicine And Pharmacology, Gastroenterology And Hepatology Keywords: ginsenoside; inflammatory bowel disease; tight junction protein; adherens junction protein; mucosal bacterial community
Online: 28 September 2023 (10:39:16 CEST)
Inflammatory bowel disease (IBD) comprises systemic inflammatory conditions primarily affecting the gastrointestinal tract, including Crohn's disease and ulcerative colitis. This research aims to analyze the clinical symptoms and pathogenesis of Dextran sodium sulfate (DSS)-induced canine IBD model, and evaluate the restorative effect of ginsenoside from a pathogenesis perspective. We established the DSS-induced canine IBD model and studied the pathological mechanisms. Additionally, we examined the therapeutic effect of ginsenosides by assessing the Canine Inflammatory Bowel Disease Activity Index (CIBDAI), C-reactive protein (CRP) levels, colonic tissue morphology, protein expression, and mucosal bacterial community analysis. Our findings revealed a total ginsenoside content of 22.7% in the ginsenoside extract. Animal experiments demonstrated that dogs with IBD exhibited decreased mental state, significantly increased CIBDAI and CRP levels, disrupted colonic epithelial tissue structure, decreased expression of mucin, tight junctions, and adherens junctions, as well as reduced diversity of the colonic mucosal bacterial community. Furthermore, correlation analysis highlighted a total of 38 bacterial strains correlated with physiological indices. Significantly, ginsenoside treatment could improve these symptoms and reverse the relative abundance of some bacterial communities. In conclusion, Alterations in the properties of the colonic mucus layer or the reduction of MUC2, its core component, in dogs with IBD can lead to bacterial penetration of the mucus layer and subsequent contact with intestinal epithelial cells, resulting in inflammation. Remarkably, ginsenoside intervention showcased the capacity to positively influence the relative abundance of bacteria and impact the colonic mucus layer properties, thereby offering promising prospects for IBD management and recovery.
ARTICLE | doi:10.20944/preprints202309.2169.v1
Subject: Environmental And Earth Sciences, Soil Science Keywords: Warming; Soil organic carbon mineralization; Temperature sensitivity; Substrate availability; Enzyme activity; Microbial community structure
Online: 30 September 2023 (09:54:19 CEST)
The subtropical forest soil plays a pivotal role in terrestrial carbon (C) cycling. Although global warming is expected to influence subtropical soil C cycling, a consensus on its impact on soil C dynamics remains elusive. Given the significant response of soil microbial respiration to temperature in subtropical soils, understanding its behavior under varying temperature regimes is critical for predicting soil organic C (SOC) responses to climate warming. We conducted a short-term laboratory soil warming incubation experiment, sampling both warmed and un-warmed soils from a subtropical plantation in southeastern China, incubating them at 20 °C, 30 °C, and 40 °C. Our aim was to study the SOC mineralization response to increasing temperatures. Our findings revealed that the temperature sensitivity (Q10) of SOC mineralization to short-term experimental warming varied between the warmed soil and the un-warmed soil. The Q10 of the un-warmed soil escalated with the temperature treatment (20-30 ℃: 1.31, 30-40℃: 1.63). Conversely, the Q10 of the warmed soil decreased (20-30 ℃:1.57, 30-40 ℃:1.41). Increasing temperature treatments enhanced hydrolytic enzyme activity but decreased soil substrate availability in both un-warmed and warmed soil. The Q10 of un-warmed soil was positively correlated with the response ratio of DOC. Additionally, soil microbial biomass exhibited a significant decline, leading to a reduced total amount of PLFAs and a decreased abundance of bacteria, fungi, and Gram-negative bacteria (GN). The changes in temperature also considerably altered the composition of the warmed soil microbial community. A drop in the microbial quotient coupled with a rise in the metabolic quotient indicated that warming amplified microbial respiration over microbial growth. The differential Q10 of SOC mineralization, in response to temperature across varying soil, can largely be attributed to shifts in soil nutrients, C-degrading enzyme activities, and microbial communities (the ratio of fungal to bacterial PLFAs).