Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 69
Filter
1.
Rapid Commun Mass Spectrom ; 38(10): e9734, 2024 May 30.
Article in English | MEDLINE | ID: mdl-38504641

ABSTRACT

RATIONALE: Malondialdehyde, one of the peroxidation products of polyunsaturated fatty acids, has been widely reported as an oxidative stress biomarker in many diseases. However, malondialdehyde is inherently unstable in biological matrices, which renders its measurement unreliable with all the reported analytical methods. To find an alternative oxidative stress biomarker, we envisioned that N-(2-carboxyethyl)proline, a modified conjugate of malondialdehyde and proline, could be a stable candidate for this purpose. METHODS: The proposed compound was chemically synthesized, and liquid chromatography-mass spectrometry methods were developed and used to search for the compound in human biological samples. RESULTS: An endogenous metabolite in human feces and urine samples was found to match the synthetic N-(2-carboxyethyl)proline by chromatographic retention and the fragmentation pattern of its molecular ion. CONCLUSION: The results confirmed that N-(2-carboxyethyl)proline was a new metabolite in human feces and urine samples. In addition, our results demonstrated a case of successful identification of true unknown metabolite by knowledge-based hypothesis of possible metabolites followed by experimental confirmation with a synthetic standard.


Subject(s)
Liquid Chromatography-Mass Spectrometry , Proline , Humans , Chromatography, Liquid/methods , Biomarkers/chemistry , Malondialdehyde
2.
J Environ Manage ; 354: 120454, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38412733

ABSTRACT

Mn-containing Li-ion batteries have become primary power sources for electronic devices and electric vehicles because of their high-energy density, extended cycle life, low cost, and heightened safety. In recent years, Li-ion batteries (LIBs) have undergone rapid updates, paralleling the swift advancement of the lithium battery industry, resulting in a growing accumulation of LIB scraps annually, necessitating comprehensive recovery strategies. This article reviews the recent progress in recovering spent Mn-containing LIBs (SM-LIBs), specifically focusing on LiMn2O4 and ternary LiCoxMnyNizO2 (NCM). Initially, the study analyzes the current resource profile of SM-LIBs and elucidates their service mechanisms. Subsequently, the study explores the recovery of SM-LIBs, discussing various methods such as the hydrometallurgical approach, combined pyrolytic treatment-wet leaching process, bioleaching pathway, and electrochemical extraction. These discussions include recovery processes, reaction principles, and technological features. In addition, this study evaluates the potential applications of these recovery technologies, considering aspects such as complexity, economic viability, energy consumption, environmental sustainability, and scalability. Finally, it summarizes the challenges associated with the comprehensive recovery and resource utilization of SM-LIBs and offers insights into future directions.


Subject(s)
Lithium , Metals , Recycling , Electric Power Supplies , Ions
3.
Front Immunol ; 14: 1291534, 2023.
Article in English | MEDLINE | ID: mdl-38149243

ABSTRACT

Background: Adaptive humoral immunity against SARS-CoV-2 has mainly been evaluated in peripheral blood. Human secondary lymphoid tissues (such as tonsils) contain large numbers of plasma cells that secrete immunoglobulins at mucosal sites. Yet, the role of mucosal memory immunity induced by vaccines or natural infection against SARS-CoV-2 and its variants is not fully understood. Methods: Tonsillar mononuclear cells (TMNCs) from adults (n=10) and children (n=11) were isolated and stimulated using positive SARS-CoV-2 nasal swabs. We used endpoint enzyme-linked immunosorbent assays (ELISAs) for the measurement of anti-S1, -RBD, and -N IgG antibody levels and a pseudovirus microneutralization assay to assess neutralizing antibodies (nAbs) in paired serum and supernatants from stimulated TMNCs. Results: Strong systemic humoral response in previously SARS-CoV-2 infected and vaccinated adults and children was observed in accordance with the reported history of the participants. Interestingly, we found a significant increase in anti-RBD IgG (305 and 834 folds) and anti-S1 IgG (475 and 443 folds) in the stimulated TMNCs from adults and children, respectively, compared to unstimulated cells. Consistently, the stimulated TMNCs secreted higher levels of nAbs against the ancestral Wuhan strain and the Omicron BA.1 variant compared to unstimulated cells by several folds. This increase was seen in all participants including children with no known history of infection, suggesting that these participants might have been previously exposed to SARS-CoV-2 and that not all asymptomatic cases necessarily could be detected by serum antibodies. Furthermore, nAb levels against both strains were significantly correlated in adults (r=0.8788; p = 0.0008) and children (r = 0.7521; p = 0.0076), and they strongly correlated with S1 and RBD-specific IgG antibodies. Conclusion: Our results provide evidence for persistent mucosal humoral memory in tonsils from previously infected and/or vaccinated adults and children against recent and old variants upon re-exposure. They also highlight the importance of targeting mucosal sites with vaccines to help control infection at the primary sites and prevent potential breakthrough infections.


Subject(s)
COVID-19 , Vaccines , Adult , Child , Humans , Immunity, Humoral , Palatine Tonsil , SARS-CoV-2 , Immunoglobulin G , Antibodies, Neutralizing
4.
Saudi J Biol Sci ; 30(10): 103809, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37766886

ABSTRACT

Intranasal live attenuated influenza vaccine (LAIV) was used to stimulate tonsillar monocular cells (MNCs) following isolation. Haemagglutinin (HA) proteins of several influenza strains were used for the detection of HA-specific IgG, IgM and IgA antibodies using ELISA. Significant anti-sH1N1 HA IgG IgA and IgM antibody titres were detected in cell culture supernatants after stimulation (mean ± SE: 0.43 ± 0.09, mean ± SE: 0.23 ± 0.04 and mean ± SE: 0.47 ± 0.05 respectively, p < 0.01). LAIV stimulation of tonsillar MNCs induced significant IgG, IgA and IgM antibodies to the pH1N1 HA (mean ± SE:1.35 ± 0.12), (mean ± SE: 0.35 ± 0.06) and (mean ± SE: 0.58 ± 0.10) respectively, p < 0.01. Surprisingly, LAIV was shown to induce cross-reactive anti-aH5N1 HA antibodies (mean ± SE: 0.84 ± 0.20, p < 0.01) to avian influenza virus (aH5N1). Anti-H2N2 HA IgG antibody was also detected in the cell culture supernatants in a significant level after LAIV stimulation (mean ± SE: 0.93 ± 0.23, p < 0.01). High levels of anti-sH3N2 HA IgG antibody was discovered after LAIV stimulation of tonsillar MNCs, (mean ± SE: 1.2 ± 0.23p < 0.01). The current model of human nasal-associated lymphoid tissue (NALT) to evaluate B cells responses to LAIV was evident that it is a successful model to study future intranasal vaccines.

5.
Bioresour Technol ; 369: 128464, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36509308

ABSTRACT

In this study, a renewable organic acid (xylonic acid), which can be prepared by the biooxidation of xylose, is used for pretreating sugarcane bagasse. The effects of reaction temperature and time on the release of fermentable xylose and glucose were investigated. On the basis of guaranteeing the good enzymatic hydrolysis efficiency and minimizing the effects of inhibitors, the pretreatment with 1 % xylnoic acid at 190 °C for 30 min was selected after optimization. In this case, 70 % xylose was released, while enzymatic hydrolysis yield was also up to 86.5 %. Meanwhile, the pretreated hydrolysate liquor was proved that it could be used for producing xylonate by biooxidation of Gluconobacter oxydans. Finally, the sequential process of the xylonic acid pretreatment and saccharification also clear the path for recycling the lignin as value-added bioproducts. Overall, this study presents a green-like strategy for fully exploiting sugarcane bagasse.


Subject(s)
Cellulose , Saccharum , Xylose , Sugars , Hydrolysis
6.
Adv Sci (Weinh) ; 9(26): e2202187, 2022 09.
Article in English | MEDLINE | ID: mdl-35853696

ABSTRACT

Current interest toward ionic liquids (ILs) stems from some of their novel characteristics, like low vapor pressure, thermal stability, and nonflammability, integrated through high ionic conductivity and broad range of electrochemical strength. Nowadays, ionic liquids represent a new category of chemical-based compounds for developing superior and multifunctional substances with potential in several fields. ILs can be used in solvents such as salt electrolyte and additional materials. By adding functional physiochemical characteristics, a variety of IL-based electrolytes can also be used for energy storage purposes. It is hoped that the present review will supply guidance for future research focused on IL-based polymer nanocomposites electrolytes for sensors, high performance, biomedicine, and environmental applications. Additionally, a comprehensive overview about the polymer-based composites' ILs components, including a classification of the types of polymer matrix available is provided in this review. More focus is placed upon ILs-based polymeric nanocomposites used in multiple applications such as electrochemical biosensors, energy-related materials, biomedicine, actuators, environmental, and the aviation and aerospace industries. At last, existing challenges and prospects in this field are discussed and concluding remarks are provided.


Subject(s)
Ionic Liquids , Nanocomposites , Electrolytes/chemistry , Ionic Liquids/chemistry , Polymers/chemistry , Solvents/chemistry
7.
Appl Biochem Biotechnol ; 194(10): 4946-4958, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35674923

ABSTRACT

Corncob as an abundant and low-cost waste resource has received increasing attention to produce value-added chemicals, it is rich in xylan and regarded as the most preferable feedstock for preparing high value added xylooligosaccharides. The use of xylooligosaccharides as core products can cut costs and improve the economic efficiency in biorefinery. In this study, maleic acid, as a non-toxic and edible acidic catalyst, was employed to pretreat corncob and produce xylooligosaccharides. Firstly, the response surface methodology experimental procedure was employed to maximize the yield of the xylooligosaccharides; a yield of 52.9% (w/v) was achieved with 0.5% maleic acid (w/v) at 155 °C for 26 min. In addition, maleic acid pretreatment was also beneficial to enhance the enzymatic hydrolysis efficiency, resulting in an enzymatic glucose yield of 85.4% (w/v) with a total of 10% solids loading. Finally, a total of 160 g of xylooligosaccharides and 275 g glucose could be produced from 1000 g corncob starting from the maleic acid pretreatment. Overall, a cascade processing for converting corncob to xylooligosaccharides and glucose by sequential maleic acid pretreatment and enzymatic hydrolysis was successfully designed for the corncob wastes utilization.


Subject(s)
Xylans , Zea mays , Glucose , Glucuronates , Hydrolysis , Maleates , Oligosaccharides
8.
Exp Biol Med (Maywood) ; 247(15): 1335-1349, 2022 08.
Article in English | MEDLINE | ID: mdl-35666095

ABSTRACT

Annual influenza vaccine is recommended to reduce the occurrence of seasonal influenza and its complications. Thus far, Madin-Darby canine kidney (MDCK) cell line has been used to manufacture cell-based influenza vaccines. Even though host microRNAs may facilitate viral replication, the interaction between MDCK cells-derived microRNAs and seasonal influenza viruses has been less frequently investigated. Therefore, this study highlighted microRNA profiles of MDCK cells to increase the yield of seasonal influenza virus production by manipulating cellular microRNAs. MDCK cells were infected with influenza A or B virus at a multiplicity of infection (MOI) of 0.01, and microRNA collections were then subjected to MiSeq (Illumina) Sequencing. The validated profiles revealed that cfa-miR-340, cfa-miR-146b, cfa-miR-197, and cfa-miR-215 were the most frequently upregulated microRNAs. The effect of candidate microRNA inhibition and overexpression on viral replication was determined using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and enzyme-linked immunosorbent assay (ELISA). The hybridization pattern between candidate miRNAs and viral genes was performed using miRBase and RNAhybrid web-based programs. Moreover, the predicted microRNA-binding sites were validated by a 3'-UTR reporter assay. The results indicated that cfa-miR-146b could directly target the PB1 gene of A/pH1N1 and the PA gene of B/Yamagata. Furthermore, cfa-miR-215 could silence the PB1 gene of A/pH1N1 and the PB1 gene of B/Victoria. However, the PB2 gene of the A/H3N2 virus was silenced by cfa-miR-197. In addition, the HA and NA sequences of influenza viruses harvested from the cell cultures treated with microRNA inhibitors were analyzed. The sequencing results revealed no difference in the antigenic HA and NA sequences between viruses isolated from the cells treated with microRNA inhibitors and the parental viruses. In conclusion, these findings suggested that MDCK cell-derived microRNAs target viral genes in a strain-specific manner for suppressing viral replication. Conversely, the use of such microRNA inhibitors may facilitate the production of influenza viruses.


Subject(s)
Influenza A virus , Influenza Vaccines , Influenza, Human , MicroRNAs , Animals , Dogs , Humans , Influenza A Virus, H3N2 Subtype/genetics , Influenza A virus/genetics , Influenza Vaccines/genetics , Kidney , Madin Darby Canine Kidney Cells , MicroRNAs/genetics , Seasons , Virus Replication/genetics
9.
Molecules ; 27(10)2022 May 12.
Article in English | MEDLINE | ID: mdl-35630579

ABSTRACT

This study investigated the effect of sweet potato starch (SPS) and konjac glucomannan (KGM) on the textural, color, sensory, rheological properties, and microstructures of plant-based pork rinds. Plant-based gels were prepared using mixtures of soy protein isolate (SPI), soy oil, and NaHCO3 supplemented with different SPS and KGM concentrations. The texture profile analysis (TPA) results indicated that the hardness, cohesiveness, and chewiness of the samples improved significantly after appropriate SPS and KGM addition. The results obtained via a colorimeter showed no significant differences were found in lightness (L*) between the samples and natural pork rinds after adjusting the SPS and KGM concentrations. Furthermore, the rheological results showed that adding SPS and KGM increased both the storage modulus (G') and loss modulus (G''), indicating a firmer gel structure. The images obtained via scanning electron microscopy (SEM) showed that the SPS and KGM contributed to the formation of a more compact gel structure. A mathematical model allowed for a more objective sensory evaluation, with the 40% SPS samples and the 0.4% KGM samples being considered the most similar to natural pork rinds, which provided a comparable texture, appearance, and mouthfeel. This study proposed a possible schematic model for the gelling mechanism of plant-based pork rinds: the three-dimensional network structures of the samples may result from the interaction between SPS, SPI, and soybean oil, while the addition of KGM and NaHCO3 enabled a more stable gel structure.


Subject(s)
Ipomoea batatas , Pork Meat , Red Meat , Animals , Colloids , Gels/chemistry , Mannans , Soybean Proteins/chemistry , Starch/chemistry , Swine
10.
Appl Biochem Biotechnol ; 194(8): 3609-3620, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35476190

ABSTRACT

As the emerging functional food additives, xylooligosaccharides are receiving high commercial interest due to their excellent gut microbiota modulation capacity, and accumulating studies have suggested that acidic hydrolysis for xylooligosaccharides preparation is the most convenient and cost-effective approach, whereas liquid acids are still limited due to the challenges in acid catalysts separation and products recovery. In the present study, a strong acidic cationic resin (NKC-9), as a recyclable solid acid catalyst, was successfully applied to xylooligosaccharides production by acidic hydrolysis of xylan. Additionally, a central composite design with response surface methodology was employed to optimize the conditions for maximizing xylooligosaccharides yields. The results suggested that xylooligosaccharides with the desired degree of polymerization (2-6) could be prepared, and the maximum yield was reached 47.7% in the case of 5% solid acid loading at 131 °C for 42 min. Finally, the recyclability of the solid acid catalysts confirmed that it was a cost-effective strategy for xylooligosaccharides production.


Subject(s)
Cation Exchange Resins , Xylans , Acids , Endo-1,4-beta Xylanases , Glucuronates , Hydrolysis , Oligosaccharides
11.
J Healthc Eng ; 2022: 8124343, 2022.
Article in English | MEDLINE | ID: mdl-35378949

ABSTRACT

Objective: The aim of this study was to evaluate whether myosin light chain kinase (MLCK) knockdown attenuated H9C2 cell hypoxia/reoxygenation (H/R) injury and downstream signaling pathway. Methods: The MLCK expression in H/R injury model H9C2 cell was determined by western blot and qRT-PCR. H/R cells were transfected with si-MLCK in the presence of P38 inhibitor (SB203580) or ERK inhibitor (U0126). Then, cell apoptosis was verified by flow cytometry. Apoptosis-related proteins were detected by western blot. The contents of reactive oxygen species (ROS), lactate dehydrogenase (LDH), superoxide dismutase (SOD), interleukin-6 (IL-6), interleukin (IL)-1ß (IL-1ß), and tumor necrosis factor-α (TNF-α) were measured using flow cytometry and colorimetric assays, respectively. Results: MLCK expression was higher in H/R cells. Knockdown of MLCK diminished the amounts of ROS, LDH, IL-6, IL-1ß, and TNF-α and elevated the release of SOD in H/R model H9C2 cells. Additionally, H/R injury induced the cumulative expression and phosphorylation of ERK and the phosphorylation of P38, whereas MLCK siRNA-treated cells showed decreased ERK1/2 and P38 activation. Inversely, P38 inhibitor (SB203580) and ERK inhibitor (U0126) could reverse the cardioprotective effects induced by si-MLCK. Conclusion: MLCK knockdown attenuated H/R injury in H9C2 cells via regulating the ERK/P38 signaling pathway. MLCK/ERK/p38 axis may provide novel insight into therapeutic targets to restrain I/R injury caused by revascularization therapy after acute myocardial infarction.


Subject(s)
Myocardial Ischemia , Myocardial Reperfusion Injury , Humans , Hypoxia/metabolism , Myocardial Reperfusion Injury/drug therapy , Myocardial Reperfusion Injury/metabolism , Myocardial Reperfusion Injury/pathology , Myosin-Light-Chain Kinase/metabolism , Myosin-Light-Chain Kinase/therapeutic use , Phosphorylation
12.
Front Nutr ; 9: 843832, 2022.
Article in English | MEDLINE | ID: mdl-35356728

ABSTRACT

In this study, soybean protein isolate (SPI) and coconut oil were emulsified and konjac flour was added to prepare the protein/polysaccharide composite emulsion gel. The SPI/polysaccharide compound fat substitute was obtained by vacuuming. The effects of protein and konjac flour addition on the gel system of the mixed emulsion were explored. Sensory evaluation experiments showed that the overall acceptability of fat substitutes added with 1% SPI was higher. With the increase of protein and konjac content, the juiciness of the samples decreased gradually. The increase of konjac content reduced the brightness of compound fat substitutes, and the yellowness of compound fat substitute increases significantly with the increase of protein content. The rheological results showed that the G' and loss modulus (G″) increased with the increase of protein and konjac content, forming a rigid elastic gel matrix, which provided a basis for the preparation of fat substitutes. Texture profile analysis (TPA) results showed that the springiness of all samples was similar to the natural fat after 20 min of heating. With the increase of protein and konjac content, the hardness of the samples increased gradually. The results of oral tribology showed that the friction coefficients of all samples were very small. The friction behavior of the samples with SPI content of 1% was similar to that of natural fat, which could better simulate the swallowing feeling and lubricity of natural fat. To sum up, the appearance of solid fat substitutes prepared with SPI and konjac flour is similar to pork fat. They show ideal functional characteristics in mechanical properties and oral tribology. Among them, the fat substitute with the protein content of 1% and konjac content of 4% is the most popular among consumers.

13.
Am J Transl Res ; 13(11): 12285-12301, 2021.
Article in English | MEDLINE | ID: mdl-34956453

ABSTRACT

OBJECTIVE: Osteosarcoma (OS) is a common bone cancer that usually influences children. Metastasis and recurrence are the main reasons for the poor prognosis. In this study, we investigated the functions and mechanisms of KCNQ1 opposite strand/antisense transcript 1 (KCNQ1OT1) in OS. METHODS: Cell viability and proliferation were detected using the CCK-8 assay and the 5-Ethynyl-2'-deoxyuridine (EdU) assay. Wound-healing assays, transwell assay and flow cytometry were used to identify cell migration, invasion, and apoptosis, respectively. The relationship among KCNQ1OT1, miR-154-3p, and KLF12 was verified by luciferase reporter assay and restricting protein immunoprecipitation (RIP) assay. Xenograft models were established to confirm the function of KCNQ1OT1 in vivo. RESULTS: The expression of KCNQ1OT1 was higher in OS than in non-tumor tissues and cells. Knockdown of KCNQ1OT1 could reduce OS cell proliferation, migration, and invasion and promoted cell death. Mechanistically, KCNQ1OT1 contributed to OS formation by acting as a competitive endogenous RNA (ceRNA) and influencing miR-154-3p expression. Furthermore, we confirmed that miR-154-3p affected KLF12 expression through binding the 3'UTR region. Finally, rescue experiments determined that KCNQ1OT1 exerted major roles in OS through the miR-154-3p/KLF12 axis. CONCLUSION: In conclusion, our research explains the mechanism of KCNQ1OT1 in OS progression, which could serve as a new therapeutic target.

14.
Biotechnol Biofuels ; 14(1): 194, 2021 Oct 01.
Article in English | MEDLINE | ID: mdl-34598725

ABSTRACT

BACKGROUND: Sunflower stalk pith, residue from the processing of sunflower, is rich in pectin and cellulose, thereby acting as an economic raw material for the acquisition of these compounds. In order to increase the commercial value of sunflower processing industry, a two-step dilute sulfuric acid treatment process was conducted on spent sunflower stalk pith to obtain the value-added products, pectin and glucose. RESULTS: In this study, pectin was firstly extracted under mild acid condition to avoid pectin degradation, which was conducted at 90 °C with a pH of 2.0 for 2 h, and ~0.14 g/g of pectin could be recovered. Then the remaining solids after pectin extraction were subjected to the reinforced treatment process with 0.75% H2SO4 at 150 °C for 30 min to further improve enzymatic hydrolysis efficiency. Moreover, by combining a fed-batch enzymatic hydrolysis strategy, a solid loading content of 16% was successfully achieved and the glucose titer reached 103.1 g/L with a yield of 83.6%. CONCLUSION: Finally, ~140 g pectin and 260 g glucose were produced from 1 kg of raw sunflower stalk pith using the integrated biorefinery process. This work puts forward a two-step dilute acid pretreatment combined with enzymatic hydrolysis method to produce pectin and glucose from sunflower spent waste.

15.
J Oncol ; 2021: 9972051, 2021.
Article in English | MEDLINE | ID: mdl-34194503

ABSTRACT

OBJECTIVE: The purpose of the study was to investigate the clinical effect of radiotherapy combined with capecitabine in rectal cancer patients after neoadjuvant therapy. METHODS: 80 rectal cancer patients who underwent neoadjuvant therapy in our hospital from February 2016 to February 2018 were selected as the study subjects and divided into the control group (n = 40) and experimental group (n = 40) according to the order of admission. Among them, the control group was treated with radiotherapy, while the experimental group was treated with radiotherapy combined with capecitabine. The therapeutic efficacy, CEA levels, the incidence and recurrence rate of adverse reactions, as well as the progression-free survival and survival rate after 2-year treatment were analyzed in the two groups. RESULTS: The effective rate of treatment in the experimental group of 87.5% (35/40) was significantly higher than 50% (20/40) in the control group, with statistical significance (X 2 = 13.09, P < 0.001). After treatment, the CEA levels in the two groups both decreased significantly, and the CEA level in the experimental group of 3.75 ± 1.76 ng/ml was significantly lower than 7.35 ± 2.11 ng/ml in the control group, with statistical significance (T = 8.29, P < 0.001). The incidence and the recurrence rate of adverse reactions of 5% (2/40) and 10% (4/40), respectively, in the experimental group were significantly lower than those of 40% (16/40) and 30% (12/40) in the control group, with statistical significance (X 2 = 14.05, 5.00, P < 0.001, 0.05). After the 2-year follow-up, it was found that the progression-free survival of 21.53 ± 6.23 months in the experimental group was significantly longer than that of 18.18 ± 5.41 months in the control group, with statistical significance (T = 2.57, P < 0.05), and the 2-year survival rate of 97.5% (39/40) in the experimental group was significantly higher than 80% (32/40) in the control group, with statistical significance (T = 6.13, P < 0.05). CONCLUSION: Radiotherapy combined with capecitabine in rectal cancer patients after neoadjuvant therapy can improve the therapeutic efficacy with fewer adverse reactions and longer patients' survival, which is worthy of popularization and application after neoadjuvant therapy for rectal cancer.

16.
J Infect Dis ; 224(8): 1305-1315, 2021 10 28.
Article in English | MEDLINE | ID: mdl-34161567

ABSTRACT

BACKGROUND: A notable feature of coronavirus disease 2019 (COVID-19) is that children are less susceptible to severe disease. Children are known to experience more infections with endemic human coronaviruses (HCoVs) compared to adults. Little is known whether HCoV infections lead to cross-reactive anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies. METHODS: We investigated the presence of cross-reactive anti-SARS-CoV-2 IgG antibodies to spike 1 (S1), S1-receptor-binding domain (S1-RBD), and nucleocapsid protein (NP) by enzyme-linked immunosorbent assays, and neutralizing activity by a SARS-CoV-2 pseudotyped virus neutralization assay, in prepandemic sera collected from children (n = 50) and adults (n = 45), and compared with serum samples from convalescent COVID-19 patients (n = 16). RESULTS: A significant proportion of children (up to 40%) had detectable cross-reactive antibodies to SARS-CoV-2 S1, S1-RBD, and NP antigens, and the anti-S1 and anti-S1-RBD antibody levels correlated with anti-HCoV-HKU1 and anti-HCoV-OC43 S1 antibody titers in prepandemic samples (P < .001). There were marked increases of anti-HCoV-HKU1 and - OC43 S1 (but not anti-NL63 and -229E S1-RBD) antibody titers in serum samples from convalescent COVID-19 patients (P < .001), indicating an activation of cross-reactive immunological memory to ß-coronavirus spike. CONCLUSIONS: We demonstrated cross-reactive anti-SARS-CoV-2 antibodies in prepandemic serum samples from children and young adults. Promoting this cross-reactive immunity and memory response derived from common HCoV may be an effective strategy against SARS-COV-2 and future novel coronaviruses.


Subject(s)
Antibodies, Viral/blood , COVID-19/immunology , Immunoglobulin G/blood , SARS-CoV-2/immunology , Adolescent , Adult , Antibodies, Viral/immunology , COVID-19/blood , COVID-19/virology , Child , Child, Preschool , Convalescence , Coronavirus 229E, Human/immunology , Coronavirus Envelope Proteins/immunology , Coronavirus OC43, Human/immunology , Cross Reactions , Enzyme-Linked Immunosorbent Assay , Female , HEK293 Cells , Humans , Immunoglobulin G/immunology , Immunologic Memory , Male , Middle Aged , Spike Glycoprotein, Coronavirus/immunology , Young Adult
18.
J Colloid Interface Sci ; 588: 476-484, 2021 Apr 15.
Article in English | MEDLINE | ID: mdl-33429344

ABSTRACT

Construction of strong metal-support interaction (SMSI) is of fundamental interest in the preparation of supported metal nanoparticle catalysts with enhanced catalytic activity. Herein, we report a facile in situ electrochemical redox tuning approach to build strong interactions between metals and supports. As for a typical example, a composite electrocatalyst of Pd-Co hybrid nanoparticles directly developed on Ni substrate is found to follow a distinct surface self-reconstruction process in alkaline media via an in situ electrochemical redox procedure, which results in structural transition from the original nanoparticles (NPs) to nanosheets (NSs) coupled with a phase transformation of the Co component, Co â†’ CoO/Co(OH)2. The SMSI is observed in the electrochemically tuned Pd-Co hybrid system and leads to significantly enhanced catalytic activity for methanol oxidation reaction (MOR) due to the modified atomic/electronic structure, increased surface area, and more exposed electroactive sites. Compared with commercial Pd/C catalyst, the electrochemically tuned Pd-Co hybrid catalyst with SMSI exhibits superior catalytic activity (2330 mA∙mgPd-1) and much better stability (remains 503 mA∙mgPd-1 after 1000 cycles and 172 mA∙mgPd-1 after 5000 s), and therefore has great potential in practical applications.

19.
J Colloid Interface Sci ; 583: 594-604, 2021 Feb 01.
Article in English | MEDLINE | ID: mdl-33039858

ABSTRACT

Herein, self-supported Ni3S2 spherical clusters packed with well-defined nanosheets developed on Ni foam (NF) were rationally fabricated via a novel low-temperature solvothermal sulfurization approach in a choline chloride/ethylene glycol (Ethaline)-based deep eutectic solvent (DES). The DES-based sulfurization process drove an interesting time-dependent surface restructuring and phase transformation that occurred on the Ni substrate, leading to the in-situ formation of a Ni3S2 layer with controllable architecture. Pre-deposition of a Ni interlayer on the NF substrate provides more assessable electrochemical surface area and reaction sites, which favored fast crystal nucleation/growth and structural reconstruction. Benefiting from the integrated design and unique 3D interdigital architecture, the optimized Ni3S2_5/Ni/NF with a sulfurization time of 5 h exhibits a high specific capacitance (specific capacity) of 5,633 mF cm-2 (860.6 µAh cm-2) at a current density of 10 mA cm-2, and maintains 87.7% of initial specific capacitance after 1,000 charge-discharge process at a current density of 20 mA cm-2. This facile DES-driven solvothermal sulfurization strategy for the fabrication of integrated metal sulfides-based electrode materials could be promising for practical applications in high-performance electrochemical devices.

20.
Viruses ; 12(4)2020 03 31.
Article in English | MEDLINE | ID: mdl-32244330

ABSTRACT

Autophagy and apoptosis are two important evolutionarily conserved host defense mechanisms against viral invasion and pathogenesis. However, the association between the two pathways during the viral infection of T lymphocytes remains to be elucidated. Simian type D retrovirus (SRV) is an etiological agent of fatal simian acquired immunodeficiency syndrome (SAIDS), which can display disease features that are similar to acquired immunodeficiency syndrome in humans. In this study, we demonstrate that infection with SRV-8, a newly isolated subtype of SRV, triggered both autophagic and apoptotic pathways in Jurkat T lymphocytes. Following infection with SRV-8, the autophagic proteins LC3 and p62/SQSTM1 interacted with procaspase-8, which might be responsible for the activation of the caspase-8/-3 cascade and apoptosis in SRV-8-infected Jurkat cells. Our findings indicate that autophagic responses to SRV infection of T lymphocytes promote the apoptosis of T lymphocytes, which, in turn, might be a potential pathogenetic mechanism for the loss of T lymphocytes during SRV infection.


Subject(s)
Apoptosis , Autophagy , Retroviruses, Simian/pathogenicity , T-Lymphocytes/pathology , Virus Replication , Autophagosomes/metabolism , Caspase 8/metabolism , Host-Pathogen Interactions , Humans , Jurkat Cells , Microtubule-Associated Proteins/metabolism , Sequestosome-1 Protein/metabolism , T-Lymphocytes/metabolism , T-Lymphocytes/virology
SELECTION OF CITATIONS
SEARCH DETAIL
...