We report acute antibody responses to SARS-CoV-2 in 285 patients with COVID-19. Within 19 days after symptom onset, 100% of patients tested positive for antiviral immunoglobulin-G (IgG). ...Seroconversion for IgG and IgM occurred simultaneously or sequentially. Both IgG and IgM titers plateaued within 6 days after seroconversion. Serological testing may be helpful for the diagnosis of suspected patients with negative RT-PCR results and for the identification of asymptomatic infections.
Full text
Available for:
FZAB, GEOZS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Natural macromolecules have attracted increasing attention due to their biocompatibility, low toxicity, and biodegradability. Pectin is one of the few polysaccharides with biomedical activity, ...consequently a candidate in biomedical and drug delivery Applications. Rhamnogalacturonan-II, a smaller component in pectin, plays a major role in biomedical activities. The ubiquitous presence of hydroxyl and carboxyl groups in pectin contribute to their hydrophilicity and, hence, to the favorable biocompatibility, low toxicity, and biodegradability. However, pure pectin-based materials present undesirable swelling and corrosion properties. The hydrophilic groups, via coordination, electrophilic addition, esterification, transesterification reactions, can contribute to pectin's physicochemical properties. Here the properties, extraction, and modification of pectin, which are fundamental to biomedical and drug delivery applications, are reviewed. Moreover, the synthesis, properties, and performance of pectin-based hybrid materials, composite materials, and emulsions are elaborated. The comprehensive review presented here can provide valuable information on pectin and its biomedical and drug delivery applications.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Efficient utilization of pesticides has presented various advantages in the ecological environment, food safety, and agricultural sustainability. Pesticide microcapsule could significantly improve ...the pesticide utilization ratio, and thus, we prepared a sustained‐release microcapsule from cellulose nanocrystal (CNCs) stabilized Pickering emulsion template. The NaCl was added to overcome the strong electrostatic repulsion among CNCs for forming a stable oil‐in‐water (O/W) CNCs‐based Pickering emulsion template, followed by crosslinking with hexamethylene diisocyanate on the interface. UV–vis and zeta‐potential were used to characterize the as‐prepared Pickering emulsion, and the stability and emulsion fraction were calculated. Results indicated that NaCl contributed to the stability of Pickering emulsion, even at a low concentration. The obtained CNCs‐based microcapsule was characterized by FT‐IR, XRD, SEM, TG‐DTG, and three‐phase contact angles. The microcapsule presented an encapsulation efficiency of 96.76% and sustained release of the imidacloprid for more than 82 h. Results indicated the potential for loading and sustained release of imidacloprid, which is beneficial to the environment, food, and agriculture.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The gut microbiota has a crucial effect on regulating the intestinal mucosal immunity and maintaining intestinal homeostasis both in health and in disease state. Many effects are mediated by gut ...microbiota-derived metabolites and tryptophan, an essential aromatic amino acid, is considered important among many metabolites in the crosstalk between gut microbiota and the host. Kynurenine, serotonin, and indole derivatives are derived from the three major tryptophan metabolism pathways modulated by gut microbiota directly or indirectly. Aryl hydrocarbon receptor (AHR) is a cytoplasmic ligand-activated transcription factor involved in multiple cellular processes. Tryptophan metabolites as ligands can activate AHR signaling in various diseases such as inflammation, oxidative stress injury, cancer, aging-related diseases, cardiovascular diseases (CVD), and chronic kidney diseases (CKD). Accumulated uremic toxins in the body fluids of CKD patients activate AHR and affect disease progression. In this review, we will elucidate the relationship between gut microbiota-derived uremic toxins by tryptophan metabolism and AHR activation in CKD and its complications. This review will provide therapeutic avenues for targeting CKD and concurrently present challenges and opportunities for designing new therapeutic strategies against renal fibrosis.
Full text
Available for:
EMUNI, FZAB, GEOZS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Cotton stalk bark fiber (CSBF) was extracted at high temperature and under high pressure, under the condition of the alkali content of 11 wt%. Experimental results proved that the extraction yield of ...CSBF was 27.3 wt%, and the residual alkali concentration was 2.1 wt%. Then five kinds of modifiers including methyl methacrylate (MMA), MMA plus initiator, epoxy propane, copper ethanolamine, and silane coupling agent were chosen to modify the surface of CSBF. It was found by measuring water retention value (WRV) that these five kinds of modifiers were all effective and the silane coupling agent was best modifier among all. The optimal modifying conditions of silane coupling agent were obtained: modifier concentration was 5%, the mixing temperature was 20°C, the mixing time was 1 h, and vacuum drying time was 1 h. Under the optimal condition, the WRV of the modified CSBF was 89%. It is expected that these modified CSBF may be a filler with strengthening effect in wood plastic composites (WPC) fields.
Full text
Available for:
FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The development of cellulose-based hydrogel has occupied a pivotal position in almost all walks of life. However, the native cellulose can not be directly used for preparing hydrogel due to the ...complex non-covalent interactions. Some literature has discussed the dissolution and modification of cellulose but has yet to address the influence of the pretreatment on the as-prepared hydrogels. Firstly, the "touching" of cellulose by derivative and non-derivative solvents was introduced, viz., the dissolution of cellulose. Secondly, the "conversion" of functional groups on the cellulose surface by special routes, viz., the modification of cellulose. The above-mentioned two parts were intended to explain the changes in physicochemical properties of cellulose by these routes and their influences on the subsequent hydrogel preparation. Finally, we summarized the "reinforcement" of cellulose-based hydrogels by physical and chemical techniques, viz., improving the mechanical properties of cellulose-based hydrogels and the changes in the multi-level structure of the interior of cellulose-based hydrogels.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Abstract
Background
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel β-coronavirus, causes severe pneumonia and has spread throughout the globe rapidly. The disease associated ...with SARS-CoV-2 infection is named coronavirus disease 2019 (COVID-19). To date, real-time reverse-transcription polymerase chain reaction (RT-PCR) is the only test able to confirm this infection. However, the accuracy of RT-PCR depends on several factors; variations in these factors might significantly lower the sensitivity of detection.
Methods
In this study, we developed a peptide-based luminescent immunoassay that detected immunoglobulin (Ig)G and IgM. The assay cutoff value was determined by evaluating the sera from healthy and infected patients for pathogens other than SARS-CoV-2.
Results
To evaluate assay performance, we detected IgG and IgM in the sera from confirmed patients. The positive rate of IgG and IgM was 71.4% and 57.2%, respectively.
Conclusions
Therefore, combining our immunoassay with real-time RT-PCR might enhance the diagnostic accuracy of COVID-19.
A peptide-based magnetic chemiluminescence enzyme immunoassay for the detection of SARS-CoV-2 antibodies was developed; 71.4% (197 of 276) and 57.2% (158 of 276) of the COVID-19 inpatients were positive for IgG and IgM against SARS-CoV-2.
Self-healing hydrogels with pH-responsiveness could protect loaded drugs from being destroyed till it arrives to the target. The pectin-based hydrogel is a candidate due to the health benefit, ...anti-inflammation, antineoplastic activity, nontoxicity, and biospecific degradation, et al. However, the abundant existence of water-soluble branched heteropolysaccharide chains influenced its performance resulting in limitation of the potential. In the present study, we prepared a series of self-healing pectin/chitosan hydrogels via the Diels-Alder reaction. Moreover, pectin/chitosan composite hydrogel was prepared as a contrast. By comparison, it can be seen that the Diels-Alder reaction greatly improved the cross-linking density of hydrogels. The self-healing experiments showed excellent self-healing performance. In different swelling mediums, significant transformation in the swelling ratio was shown, indicating well-swelling property, pH- and thermo-responsiveness. The drug loading and release studies presented high loading efficiency and sustained release performance. The cytotoxicity assay that showed a high cell proliferation ratio manifested great cytocompatibility.
Display omitted
•Diels-Alder reaction was firstly employed to prepare self-healing pectin/chitosan hydrogel.•The crosslinking density was mainly controlled by the Diels-Alder reaction.•The obtained hydrogel presented a high swelling ratio and pH-responsiveness.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Natural macromolecules have been used to adsorb pollutants including heavy metal ions and organic dyes due to low-cost, accessible, biodegradable, and eco-friendly advantages. Pectin, an important ...natural polymer, possesses abundant carboxyl and hydroxyl functional groups that can interact with the metal and organic cations via electrostatic interaction; as well as be modified by other chemicals for preparing hybrid and composite materials. The resultant materials have been employed to remove pollutants from aqueous solution; the importance of chemical composition was unlocked. Here, we reviewed contaminant removal by pectin, and pectin-based hybrid and composite materials, and highlighted the role of functional groups on pollutant removal. The removal of heavy metal ions was mainly due to surface coordination, while that of organic cations to electrostatic interactions of the functional groups. Moreover, the influence of initial contaminant concentration was critically discussed. The comprehensive review can provide valuable information on pectin and its application in contaminant removal.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Injectable hydrogels with self-healing ability present great potential for drug delivery. They could be facilely implanted in vivo and maintained structural and functional integrity till the hydrogel ...arriving at target sites. Herein, a series of injectable and self-healing composite hydrogel were developed as delivery vehicles for anti-cancer drug. The hydrogels were obtained with varying ratios of oxidized pectin/chitosan to nano γ-Fe2O3, which present excellent injectable, self-healing, magnetic, high biocompatible, and anti-cancer properties. The nano γ-Fe2O3 with particle size of about 0.25 μm loaded on the surface of hydrogel. Magnetic hysteresis loops of the hydrogel presented S-shape over the applied magnetics and the MS value was 4.86 emu/g. When pH dropped from 7.4 to 6.5 or temperature increased form 36 °C to 37 °C, the percentage increase in the swelling rate of OP4-400 reached to 35.89% and 25.13%, respectively. The composite hydrogels could continuously release water-soluble 5-FU for more than 12 h. In addition, the drug delivery systems indicated acceptable anti-cancer property though trace amounts of 5-FU were added in the hydrogel systems. The addition of γ-Fe2O3 could not only be beneficial to the targeting but also collectively enhance the anti-cancer property.
Display omitted
•γ-Fe2O3 was firstly introduced into pectin/chitosan hydrogel to enhance anti-cancer properties.•Injectability and self-healing property of pectin/chitosan/γ-Fe2O3 hydrogel was firstly studied.•The hydrogels present high injectable, self-healing, pH- and thermo-sensitive performance.•The γ-Fe2O3 significantly enhanced the anti-cancer properties without decreasing biocompatibility.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
PDF
