The oxidized κ-carrageenans with different oxidation levels were prepared through the hydrogen peroxide and copper sulfate redox system. The oxidation level of oxidized κ-carrageenan was successfully controlled by adjusting the dosage of hydrogen peroxide. The results showed that the microtopography of oxidized κ-carrageenan changed from rough granules to smooth flakes, mainly resulting from the easily melting property of oxidized κ-carrageenan induced by introduced carboxyl and aldehyde groups. Especially, the antibacterial activity of oxidized κ-carrageenans against Gram-positive bacteria (Staphylococcus aureus and Listeria monocytogenes) and Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa) was systematically investigated. The results showed that the oxidized κ-carrageenan could damage the bacterial cell wall and cytoplasmic membrane and suppress the growth of both Gram-positive and Gram-negative bacteria. The oxidized κ-carrageenan possessed broad-spectrum antibacterial activity, which may be used as a new antibacterial agent.
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http://dx.doi.org/10.1016/j.carbpol.2017.07.029 | DOI Listing |
J Am Chem Soc
January 2025
Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, P. R. China.
Effective delivery and controlled release of metallo-prodrugs with sustained activation and rapid response feed the needs of precise medicine in metal chemotherapeutics. However, gold-based anticancer drugs often suffer from detoxification binding and extracellular transfer by sulfur-containing peptides. To address this challenge, we integrate a thiol-activated prodrug strategy of newly prepared hypercoordinated carbon-centered gold(I) clusters (HCGCs) with their photosensitization character to augment the mitochondrial release of Au(I) in tumors.
View Article and Find Full Text PDFNano Lett
January 2025
Key Lab for the Physics and Chemistry of Nanodevices and Center for Carbon-based Electronics, School of Electronics, Peking University, Beijing 100871, China.
One-time programmable (OTP) memory is an essential component in chips, which has extremely high security to protect the stored critical information from being altered. However, traditional OTP memory based on the thermal breakdown of the dielectric has a large programming current, which leads to high power consumption. Here, we report a gate tunneling-induced "cold" breakdown phenomenon in carbon nanotube (CNT) field-effect transistors, and based on this we construct a "cold" fuse (C-fuse) memory where applying a mild gate voltage can break down the CNT channel without damaging the gate dielectric.
View Article and Find Full Text PDFHistol Histopathol
January 2025
Department of Neurology, The Affiliated People's Hospital of Jiangsu University, Zhenjiang Jiangsu, PR China.
Parkinson's disease (PD) is a limb movement disorder caused by the degeneration of brain neurons and seriously affects the quality of life of the elderly. However, the current drugs are symptomatic treatments that cannot prevent or delay the development of the disease. Targeted therapy for pathogenesis may be the direction of development in the future.
View Article and Find Full Text PDFStroke
January 2025
Wolfson Centre for the Prevention of Stroke and Dementia, Nuffield Department of Clinical Neurosciences, University of Oxford, United Kingdom. (D.M.K., P.M.R.).
Cardiovascular diseases such as stroke are a major cause of morbidity and mortality for patients with chronic kidney disease (CKD). The underlying mechanisms connecting CKD and cardiovascular disease are yet to be fully elucidated, but inflammation is proposed to play an important role based on genetic association studies, studies of inflammatory biomarkers, and clinical trials of anti-inflammatory drug targets. There are multiple sources of both endogenous and exogenous inflammation in CKD, including increased production and decreased clearance of proinflammatory cytokines, oxidative stress, metabolic acidosis, chronic and recurrent infections, dialysis access, changes in adipose tissue metabolism, and disruptions in intestinal microbiota.
View Article and Find Full Text PDFMediators Inflamm
January 2025
Institute of Digestive Diseases, Xiyuan Hospital of China Academy of Chinese Medical Sciences, Beijing, China.
This study aims to reveal the potential molecular mechanisms of modified Gegen Qinlian decoction (MGQD) in relieving ulcerative colitis (UC). C57BL/6J mice were used to establish experimental colitis via dextran sodium sulfate (DSS). Body weight, disease activity index (DAI), spleen weight, colon length, and histopathologic features were measured to evaluate the therapeutic effects of MGQD on mice with UC.
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