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This research aimed to synthesize Chitosan/PVA-blank and a series of Cs/PVA/Sepolite based pH-sensitive membranes using a solution casting process. The synthesized Cs/PVA-blank and Cs/PVA/Sep based membranes were investigated via SEM, FTIR, XRD, and TGA techniques. The SEM results of Cs/PVA/Sep based membrane reveal that the hydrolytic stability and strength were improved in acidic and basic media owing to the incorporation of sepiolite content into chitosan. The characteristic band at 3741 cm-1 in the FTIR spectra of the Cs/PVA/Sep membrane confirmed the successful synthesis. The obtained XRD results showed higher d-spacing for Cs/PVA/Sep membranes as compared to the Cs/PVA-blank membranes owing to the intercalation of chitosan in the interlayer spacing of the sepiolite. The obtained TGA results show higher thermally stability for Cs/PVA/Sep membrane as compared to the Cs/PVA-blank sample due to the interaction of sepiolite content with the chitosan matrix. The obtained hydrolytic and swelling studies revealed that the Cs/PVA/Sep membrane displayed enhanced stability in basic and neutral media while showing minimum swelling in an acidic medium. The water uptake ability was checked for Cs/PVA/-blank and Cs/PVA/Sep-60% membrane and the results exhibited that the Cs/PVA/-blank membrane had maximum water uptake value as compared to the Cs/PVA/Sep-60% membrane. While those with a considerable amount of filler had the lowest water uptake values. As Sepolite content increased, the water uptake % values decreases because of weakness in H-bonding (of hydrophilic groups) and due to intercalation in Sepolite layers during polymer formation.
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Quitosana , Polímeros Responsivos a Estímulos , Concentração de Íons de Hidrogênio , ÁguaRESUMO
Kaempferol, a flavonoid derived from various herbs such as cocoyam, propolis, and grapefruit, has garnered interest due to its numerous pharmacological benefits, including anti-inflammatory, antioxidant, and anti-diabetic properties. Kaempferol has been shown to possess notable anti-tumour bioactivity, indicating potential for treating gynaecological malignancies. To date, numerous studies have demonstrated the potential of kaempferol to induce tumour cell apoptosis, inhibit proliferation, and prevent metastasis and invasion in several gynaecological malignancies, including breast, ovarian and endometrial cancers. However, there is currently insufficient research investigating the efficacy of kaempferol for the treatment of gynaecological malignancies, and a lack of systematic review of its mechanism of action. Therefore, this review is founded on a literature analysis of the anticancer effects of kaempferol on gynaecological malignancies. The goal is to provide valuable reference material for scientific researchers and medical practitioners.
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Background: Although inactivated COVID-19 vaccines are proven to be safe and effective in the general population, the dynamic response and duration of antibodies after vaccination in the real world should be further assessed. Methods: We enrolled 1067 volunteers who had been vaccinated with one or two doses of CoronaVac in Zhejiang Province, China. Another 90 healthy adults without previous vaccinations were recruited and vaccinated with three doses of CoronaVac, 28 days and 6 months apart. Serum samples were collected from multiple timepoints and analyzed for specific IgM/IgG and neutralizing antibodies (NAbs) for immunogenicity evaluation. Antibody responses to the Delta and Omicron variants were measured by pseudovirus-based neutralization tests. Results: Our results revealed that binding antibody IgM peaked 14-28 days after one dose of CoronaVac, while IgG and NAbs peaked approximately 1 month after the second dose then declined slightly over time. Antibody responses had waned by month 6 after vaccination and became undetectable in the majority of individuals at 12 months. Levels of NAbs to live SARS-CoV-2 were correlated with anti-SARS-CoV-2 IgG and NAbs to pseudovirus, but not IgM. Homologous booster around 6 months after primary vaccination activated anamnestic immunity and raised NAbs 25.5-fold. The neutralized fraction subsequently rose to 36.0% for Delta (p=0.03) and 4.3% for Omicron (p=0.004), and the response rate for Omicron rose from 7.9% (7/89)-17.8% (16/90). Conclusions: Two doses of CoronaVac vaccine resulted in limited protection over a short duration. The inactivated vaccine booster can reverse the decrease of antibody levels to prime strain, but it does not elicit potent neutralization against Omicron; therefore, the optimization of booster procedures is vital. Funding: Key Research and Development Program of Zhejiang Province; Key Program of Health Commission of Zhejiang Province/ Science Foundation of National Health Commission; Major Program of Zhejiang Municipal Natural Science Foundation; Explorer Program of Zhejiang Municipal Natural Science Foundation.
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Vacinas contra COVID-19 , COVID-19 , Adulto , Humanos , Estudos de Coortes , Estudos Transversais , COVID-19/prevenção & controle , SARS-CoV-2 , Anticorpos Neutralizantes , Imunoglobulina G , Anticorpos Antivirais , ChinaRESUMO
Hexavalent chromium (Cr(VI)) and methyl orange (MO) are highly toxic and difficult to treat. Electron beam irradiation (EB) can produce ·OH, H·, ·O2-, hydrated electron (eaq-) and other active substances, which have strong redox ability to pollutants. However, the penetration capacity of EB is limited (the penetration depth of water is 10 cm). Therefore, the photocatalytic method of graphitic carbon nitride (CN) was used as the synergistic method of EB in this project to degrade Cr(VI) and MO. The results showed that the maximum treatment efficiency of 100 mg L-1 Cr(VI) and 50 mg L-1 MO with liquid surface height of 5 cm was 95.0% and 99.1%, respectively, which was much higher than that of single photocatalytic method (39.5%, 23.4%) and EB (79.6%, 92.1%), and the efficiency of synergistic treatment was higher under acidic condition. When the liquid depth increased to 30 cm, the efficiency of synergistic system decreased by 14.7% and 15.2% for the degradation of Cr(VI) and MO, respectively, less than the single EB treatment (47.2%, 45.7%). Additionally, the performance of the morphology, the light absorption performance, and the separation of photogenerated electron-hole pairs of the CN were evaluated before and after the synergistic system. Lastly, the mechanism illustrates that the electron and thermal effects of EB, eaq-, photogenerated electrons played key roles for the Cr(VI) reduction, and the electron and thermal effects of EB, ·O2-, photogenerated holes played key roles for the MO degradation. This study provides a new opportunity for the synergistic system of photocatalyst and EB in the treatment of pollutants.
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Cromo , Elétrons , Compostos Azo , Catálise , Grafite , Compostos de NitrogênioRESUMO
An efficient decoloration method for polysaccharides from the sprouts of Toona sinensis (A. Juss.) Roem (PSTS) by anion exchange macroporous resins (AEMR) was investigated in the present paper. The results suggested that D941 resin offered better decoloration efficiency than other tested resins. Based on single-factor experiments, the optimal decoloration parameters of D941 resin were obtained as follows: temperature of 45°C, sample initial concentration of 30mg/ml, pH value of 8.5, static decoloration time of 90min, dynamic decoloration processing volume of 5.5BV with the flow rate of 2BV/h. Decoloration ratio, PSTS recovery ratio and selectivity coefficient were 91.94±1.23%, 90.05±2.35% and 10.92±0.63, respectively. Most of pigment impurities were successfully removed from PSTS solutions after treated by D941 resin, and there was no significant difference in carbohydrate concentration, characteristic groups and molecular weight. Compared with H2O2 oxidation and activated carbon adsorption, this developed method is superior.