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1.
Small ; 20(15): e2307184, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38012533

ABSTRACT

Aqueous zinc-ion hybrid capacitors (ZIHCs), as ideal candidates for high energy-power supply systems, are restricted by unsatisfied energy density and poor cycling durability for further applications. The construction of a surface-functionalized carbon cathode is an effective strategy for improving the performance of ZIHCs. Herein, a high-performance ZIHC is achieved using oxygen-rich hierarchically porous carbon rods (MDPC-X) prepared by the pyrolysis of a metal-organic framework (MOF) assisted by KOH activation. The MDPC-X samples displayed high electric double-layer capacitance (EDLC) and pseudocapacitance owing to their oxygen-rich surfaces, abundant electroactive sites, and short ions/electron transfer lengths. The surface oxygen functional groups for the reversible chemical adsorption/desorption of Zn2+ are identified using ex situ X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). Consequently, the as-assembled ZIHC exhibited a high capacity of 323.4 F g-1 (161.7 mA h g-1) at 0.5 A g-1 and a retention of 147 F g-1 (73.5 mA h g-1) at an ultrahigh current density of 50 A g-1, corresponding to high energy and power densities of 145.5 W h kg-1 and 45 kW kg-1, respectively. Furthermore, an excellent cycling life with 96.5% of capacity retention is also maintained after 10 000 cycles at 10 A g-1, demonstrating its promising potential for applications.

2.
Protein Expr Purif ; 219: 106473, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38508543

ABSTRACT

Recombinant human collagens have attracted intensive interest in the past two decades, demonstrating considerable potential in medicine, tissue engineering, and cosmetics. Several humanized recombinant collagens have been produced, exhibiting similar characteristics as the native species. To get insight into the structural and bioactive properties of different parts of collagen, in this study, the segment of Gly300-Asp329 of type III collagen was first adopted and repeated 18 times to prepare a novel recombinant collagen (named rhCLA). RhCLA was successfully expressed in E. coli, and a convenient separation procedure was established through reasonably combining alkaline precipitation and acid precipitation, yielding crude rhCLA with a purity exceeding 90%. Additionally, a polishing purification step utilizing cation exchange chromatography was developed, achieving rhCLA purity surpassing 98% and an overall recovery of approximately 120 mg/L culture. Simultaneously, the contents of endotoxin, nucleic acids, and host proteins were reduced to extremely low levels. This fragmented type III collagen displayed a triple-helical structure and gel-forming capability at low temperatures. Distinct fibrous morphology was also observed through TEM analysis. In cell experiments, rhCLA exhibited excellent biocompatibility and cell adhesion properties. These results provide valuable insights for functional studies of type III collagen and a reference approach for the large-scale production of recombinant collagens.


Subject(s)
Collagen Type III , Escherichia coli , Recombinant Proteins , Humans , Collagen Type III/chemistry , Collagen Type III/genetics , Collagen Type III/biosynthesis , Collagen Type III/metabolism , Collagen Type III/isolation & purification , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/isolation & purification , Recombinant Proteins/biosynthesis , Escherichia coli/genetics , Escherichia coli/metabolism , Cell Adhesion
3.
Small ; 19(49): e2304172, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37563809

ABSTRACT

As a promising low-cost and high-safety energy storage candidate, zinc-ion hybrid capacitors (ZIHCs) have received extensive attention. For maximizing the advantages of ZIHC with high energy density and high power density, the structural engineering of the porous carbon materials is the crucial and effective strategy. Herein, an oxygen-enriched hierarchical porous carbon has been fabricated from the pyrolysis of olive leaves combing the chemical activation. The abundant interfacial active sites and short ions/electrons transfer length endow the hierarchical porous carbon cathode with high ions adsorption capacity and fast kinetic behaviors. Meanwhile, the oxygen-rich functional groups can provide extra pseudocapacitance and improve the wettability and conductivity of porous carbon. Benefiting from these advantages, an anti-self-discharge ZIHC device with a high energy-power feature has been assembled. The electrochemical process is studied by ex situ X-ray diffraction (XRD) and scanning electron microscope (SEM) methods. Finally, an excellent energy density of 136.3 W h kg-1 , and high power output of 20 kW kg-1 , as well as long cycle life with 91% capacity retention over 20 000 cycles at 10 A g-1 are realized by as-assembled ZIHC.

4.
Protein Expr Purif ; 204: 106231, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36623711

ABSTRACT

Recombinant virus-like particles (VLP) with single capsid protein have been successfully produced through prokaryotic system, but for those with multiple capsid proteins such as the foot-and-mouth disease virus (FMDV), this approach is more challenging. In this study, in vitro assembly of FMDV VLP was investigated with its capsids VP1, VP2 and VP3 separately expressed as inclusion bodies. After extraction and solubilization, three capsids were purified in denatured state through a flow-through model, increasing its purity to 90%. VLP assembly for FMDV was observed after diluting the mixture of denatured capsids in the ration of 1: 1: 1, while no VLP appeared if the separately diluted and refolded capsids were co-incubated. This result suggests certain synergetic interactions exist among the three capsids, which are crucial for FMDV VLP assembly. Sodium chloride and capsid protein concentration both greatly affect the assembling efficiency. After purification through size exclusion chromatography, VLP with similar diameter and morphology as inactivated FMDV were obtained, which elicited high IgG titers and B cell activation when vaccinated in mouse. It could also induce specific humoral and cellular immune responses in splenocytes proliferative experiments. Our study demonstrated the feasibility of in vitro assembling FMDV VLP from inclusion bodies of VP1, VP2 and VP3 for the first time.


Subject(s)
Artificial Virus-Like Particles , Capsid Proteins , Foot-and-Mouth Disease Virus , Foot-and-Mouth Disease , Virus Assembly , Animals , Mice , Capsid Proteins/chemistry , Foot-and-Mouth Disease/prevention & control , Foot-and-Mouth Disease Virus/chemistry , Inclusion Bodies , Artificial Virus-Like Particles/chemistry
5.
Stem Cells ; 39(2): 183-195, 2021 02.
Article in English | MEDLINE | ID: mdl-33252829

ABSTRACT

Hematopoietic stem cells (HSCs) maintain quiescence under steady state; however, they are compelled to proliferate and expand to replenish the blood system under stress. The molecular basis underlying stress hematopoiesis remains to be fully understood. In this study, we reported that IRF7 represents an important regulator of stress hematopoiesis. Interferon regulatory factor 7 (IRF7) was dispensable for normal hematopoiesis, whereas its deficiency significantly enhanced hematopoietic stem and progenitor cells (HSPCs) regeneration and improved long-term repopulation of HSCs under stress. Mechanistic studies showed that CXCR4 was identified as a downstream target of IRF7. Overexpression of CXCR4 abrogated the enhanced proliferation and regeneration of IRF7-deficient HSPCs under stress. Similar results were obtained in HSCs from human umbilical cord blood. These observations demonstrated that IRF7 plays an important role in hematopoietic regeneration under stress.


Subject(s)
Cord Blood Stem Cell Transplantation/methods , Hematopoiesis/physiology , Interferon Regulatory Factor-7/metabolism , Oxidative Stress/physiology , Receptors, CXCR4/metabolism , Animals , Cells, Cultured , Fetal Blood/metabolism , Fetal Blood/transplantation , Humans , Interferon Regulatory Factor-7/antagonists & inhibitors , Interferon Regulatory Factor-7/genetics , Mice , Mice, Inbred C57BL , Mice, Knockout , Receptors, CXCR4/genetics
6.
J Immunol ; 205(3): 842-852, 2020 08 01.
Article in English | MEDLINE | ID: mdl-32571839

ABSTRACT

Secretory Ig A (sIgA) plays an important role in the maintenance of intestinal homeostasis via cross-talk with gut microbiota. The defects in sIgA production could elicit dysbiosis of commensal microbiota and subsequently facilitate the development of inflammatory bowel disease. Our previous study revealed activating transcription factor 3 (ATF3) as an important regulator of follicular helper T (TFH) cells in gut. ATF3 deficiency in CD4+ T cells impaired the development of gut TFH cells, and therefore diminished sIgA production, which increased the susceptibility to murine colitis. However, the potential role of microbiota in ATF3-mediated gut homeostasis remains incompletely understood. In this study, we report that both Atf3-/- and CD4creAtf3fl/fl mice displayed profound dysbiosis of gut microbiota when compared with their littermate controls. The proinflammatory Prevotella taxa, especially Prevotella copri, were more abundant in ATF3-deficient mice when compared with littermate controls. This phenotype was obviously abrogated by adoptive transfer of either TFH cells or IgA+ B cells. Importantly, depletion of gut microbiota dramatically alleviated the severity of colitis in Atf3-/- mice, whereas transfer of microbiota from Atf3-/- mice to wild-type recipients increased their susceptibility to colitis. Collectively, these observations indicate the importance of IgA-microbiota interaction in ATF3-mediated gut homeostasis.


Subject(s)
Activating Transcription Factor 3/immunology , B-Lymphocytes/immunology , Gastrointestinal Microbiome/immunology , Homeostasis/immunology , Immunoglobulin A/immunology , T Follicular Helper Cells/immunology , Activating Transcription Factor 3/genetics , Animals , Dysbiosis/genetics , Dysbiosis/immunology , Dysbiosis/microbiology , Homeostasis/genetics , Immunoglobulin A/genetics , Mice , Mice, Knockout , Prevotella/immunology
7.
Proc Natl Acad Sci U S A ; 116(13): 6286-6291, 2019 03 26.
Article in English | MEDLINE | ID: mdl-30862736

ABSTRACT

Disruption of mucosal immunity plays a critical role in the pathogenesis of inflammatory bowel disease, yet its mechanism remains not fully elucidated. Here, we found that activating transcription factor 3 (ATF3) protects against colitis by regulating follicular helper T (TFH) cells in the gut. The expression of ATF3 in CD4+ T cells was negatively correlated with the severity of ulcerative colitis in clinical patients. Mice with ATF3 deficiency in CD4+ T cells (CD4creAtf3fl/fl ) were much more susceptible to dextran sulfate sodium-induced colitis. The frequencies of TFH cells, not other T cell subsets, were dramatically decreased in Peyer's patches from CD4creAtf3fl/fl mice compared with Atf3fl/fl littermate controls. The defective TFH cells significantly diminished germinal center formation and IgA production in the gut. Importantly, adoptive transfer of TFH or IgA+ B cells caused significant remission of colitis in CD4creAtf3fl/fl mice, indicating the TFH-IgA axis mediated the effect of ATF3 on gut homeostasis. Mechanistically, B cell lymphoma 6 was identified as a direct transcriptional target of ATF3 in CD4+ T cells. In summary, we demonstrated ATF3 as a regulator of TFH cells in the gut, which may represent a potential immunotherapeutic target in colitis.


Subject(s)
Activating Transcription Factor 3/immunology , Activating Transcription Factor 3/pharmacology , Colitis/drug therapy , Colitis/immunology , T-Lymphocytes, Helper-Inducer/drug effects , T-Lymphocytes, Helper-Inducer/immunology , Activating Transcription Factor 3/genetics , Activating Transcription Factor 3/metabolism , Adoptive Transfer , Animals , B-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/drug effects , CD4-Positive T-Lymphocytes/immunology , Colitis/pathology , Colitis, Ulcerative , Colon/pathology , Dextran Sulfate/adverse effects , Disease Models, Animal , Gene Expression Profiling , Homeostasis , Immunity, Mucosal/immunology , Immunoglobulin A , Immunotherapy , Mice , Peyer's Patches/immunology , T-Lymphocyte Subsets
8.
Transp Res Part A Policy Pract ; 155: 128-141, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34728910

ABSTRACT

The COVID-19 pandemic has brought unprecedented disruptions to many industries, and the transportation industry is among the most disrupted ones. We seek to address, in the context of a ride-sharing platform, the response of drivers to the pandemic and the post-pandemic recovery. We collected comprehensive trip data from one of the leading ride-sharing companies in China from September 2019 to August 2020, which cover pre-, during-, and post-pandemic phases in three major Chinese cities, and investigate the causal effect of the COVID-19 pandemic on driver behavior. We find that drivers only slightly reduce their number of shifts in response to increased COVID-19 cases, likely because they have to make a living from providing ride-sharing services. Nevertheless, conditional on working, drivers exhibit strong risk aversion: As the number of new cases increases, drivers strategically adjust the scope of their search for passengers, complete fewer trips, and as a result, make lower daily earnings. Finally, our heterogeneity analyses indicate that the effects appear to vary both across drivers and over time, with generally stronger effects on drivers who are older, more experienced, more active before the pandemic, and higher-status within the firm. Our findings have strong policy implications: These drivers tend to contribute more to the focal company, and also rely more on providing ride-sharing services to make a living. Therefore, they should be prioritized in stimulus plans offered by the government or the ride-sharing company.

9.
Protein Expr Purif ; 178: 105747, 2021 02.
Article in English | MEDLINE | ID: mdl-32898688

ABSTRACT

Structure heterogeneity and host nucleic acids contamination are two major problems for virus-like particles (VLPs) produced by various host cells. In this study, an in vitro optimized disassembly-purification-reassembly process was developed to obtain uniform and nucleic acid free hepatitis B core (HBc) based VLPs from E. coli fermentation. The process started with ammonium sulfate precipitation of all heterogeneous HBc structures after cell disintegration. Then, dissolution and disassembly of pellets into basic subunits were carried out under the optimized disassembly condition. All contaminants, including host nucleic acids and proteins, were efficiently removed with affinity chromatography. The purified subunits reassembled into VLPs by final removal of the chaotropic agent. Two uniform and nucleic acid free HBc-based VLPs, truncated HBc149 and chimeric HBc183-MAGE3 I, were successfully prepared. It was found that disassembly degree of HBc-based VLPs had a great influence on the protein yield, nucleic acid removal and reassembly efficiency. 4 M urea was optimal because lower concentration would not disassemble the particles completely while higher concentration would further denature the subunits into disordered aggregate and could not be purified and reassembled efficiently. For removal of strong binding nucleic acids such as in the case of HBc183-MAGE3 I, benzonase nuclease was added to the disassembly buffer before affinity purification. Through the optimized downstream process, uniform and nucleic acid free HBc149 VLPs and HBc183-MAGE3 I VLPs were obtained with purities above 90% and yields of 55.2 and 43.0 mg/L, respectively. This study would be a reference for efficient preparation of other VLPs.


Subject(s)
Hepatitis B Core Antigens , Hepatitis B virus , Virion , Escherichia coli/chemistry , Escherichia coli/genetics , Escherichia coli/metabolism , Hepatitis B Core Antigens/biosynthesis , Hepatitis B Core Antigens/chemistry , Hepatitis B Core Antigens/isolation & purification , Hepatitis B virus/chemistry , Hepatitis B virus/genetics , Nucleic Acids/chemistry , Virion/chemistry , Virion/isolation & purification , Virion/metabolism
10.
Eur Radiol ; 31(8): 5851-5862, 2021 Aug.
Article in English | MEDLINE | ID: mdl-33585991

ABSTRACT

OBJECTIVE: To evaluate the efficacy and safety of stent placement combined with intraluminal radiofrequency ablation (intra-RFA) and hepatic arterial infusion chemotherapy (HAIC) for patients with advanced biliary tract cancers (Ad-BTCs) and biliary obstruction (BO). METHODS: We retrospectively reviewed data for patients with Ad-BTCs and BO who underwent stent placement with or without intra-RFA and HAIC in three centres between November 2013 and November 2018. The stent patency time (SPT), overall survival (OS), and adverse events (AEs) were analysed. RESULTS: Of the 135 enrolled patients, 64 underwent stent placement combined with intra-RFA and HAIC, while 71 underwent only stent placement. The median SPT was significantly longer in the combination group (8.2 months, 95% confidence interval [CI]: 7.1-9.3) than in the control group (4.3 months, 95% CI: 3.6-5.0; p < 0.001). A similar result was observed for OS (combination: 13.2 months, 95% CI: 11.1-16.5; control: 8.5 months, 95% CI: 7.6-9.6; p < 0.001). The incidence of AEs related to biliary tract operation was not significantly different between the two groups (p > 0.05). The most common AE and serious AE related to HAIC were alanine aminotransferase elevation (24/64; 37.5%) and thrombocytopenia (8/64; 12.5%), respectively. All AEs were tolerable, and there was no death from AEs. CONCLUSIONS: Stent placement combined with intra-RFA and HAIC may be a safe, potential treatment strategy for patients with Ad-BTCs and BO. KEY POINTS: • Advanced biliary cancers (Ad-BTCs) with biliary obstruction (BO) can rapidly result in liver failure and cachexia with an extremely poor prognosis. • Stent placement combined with intraluminal radiofrequency ablation and hepatic arterial infusion chemotherapy may be safe and effective for patients with Ad-BTCs and BO. • The long-term efficacy and safety of the combined treatment is promising.


Subject(s)
Biliary Tract Neoplasms , Catheter Ablation , Cholestasis , Radiofrequency Ablation , Biliary Tract Neoplasms/complications , Biliary Tract Neoplasms/therapy , Cholestasis/surgery , Humans , Retrospective Studies , Stents , Treatment Outcome
11.
J Immunol ; 203(4): 864-872, 2019 08 15.
Article in English | MEDLINE | ID: mdl-31243090

ABSTRACT

Cyclooxygenase (COX)-1, one of the critical enzymes required for the conversion of arachidonic acid to PGs, has been demonstrated to play an important role not only in the cardiovascular system but also in the immune system. COX-1 has been found to regulate early B cell differentiation, germinal center formation, and Ab production of B cells. However, the underlying mechanisms of COX-1-mediated B cell activation remains not fully understood. In this study, we reported that COX-1 is a potential regulator for the development of follicular Th (TFH) cells. COX-1-deficient (COX-1-/- ) mice displayed a significant reduction of TFH cells upon influenza infection or immunization with keyhole limpet hemocyanin, which led to a severe impairment of germinal center responses. We further demonstrated that COX-1-derived PGE2, via binding with its receptors EP2/EP4, represents the underlying mechanism. The administration of EP2/EP4 agonists or PGE2 almost completely rescued the defective TFH cell generation in COX-1-/- mice. Taken together, our observations indicate that COX-1 plays an important role in the development of TFH cells.


Subject(s)
Cyclooxygenase 1/immunology , Dinoprostone/immunology , Lymphocyte Activation/immunology , T-Lymphocytes, Helper-Inducer/immunology , Animals , Cell Differentiation/immunology , Germinal Center/immunology , Mice , Mice, Inbred C57BL , Mice, Knockout , T-Lymphocytes, Helper-Inducer/cytology
12.
Virol J ; 17(1): 58, 2020 04 22.
Article in English | MEDLINE | ID: mdl-32321526

ABSTRACT

BACKGROUND: Prophylactic vaccines are critical in preventing hand, foot, and mouth disease (HFMD) primarily caused by human enterovirus 71 (EV71) infection. Children aged less than 5 years are especially susceptible to EV71 infections. In addition to the development of vaccines containing the inactivated virus, those containing virus-like particles (VLPs) with repeated antigens also constitute an effective preventive strategy for EV71 infections, with safety and productivity advantages. We previously developed a fusion protein composed with truncated peptides of the EV71 capsid protein, which assembled into spherical particles. This study aimed to assess the immunoprotective effects of this fusion protein as a vaccine candidate in a mouse model of EV71 infection. METHODS: To evaluate the protective effect of fusion protein vaccine candidate, neonatal mice born by immunized female mice, as well as normal neonatal mice immunized twice were infected with EV71 virus. Whereafter, the survival rates, clinical scores and viral loads were measured. RESULTS: The high dosage and booster immunization helped induce specific serum antibodies with high neutralization titers, which were transferred to neonatal mice, thereby facilitating effective resistance towards EV71 infection. An active immune response was also observed in neonatal mice which generated following immunization. CONCLUSIONS: The present results suggest that this fusion protein is a suitable vaccine candidate in treating EV71 infections.


Subject(s)
Enterovirus A, Human/genetics , Enterovirus Infections/prevention & control , Peptides/immunology , Viral Fusion Proteins/immunology , Viral Vaccines/immunology , Animals , Animals, Newborn , Antibodies, Neutralizing/blood , Antibodies, Viral/blood , Cell Line, Tumor , Enterovirus A, Human/immunology , Enterovirus Infections/immunology , Female , Humans , Immunization, Secondary , Mice , Mice, Inbred BALB C , Peptides/genetics , Viral Fusion Proteins/administration & dosage , Viral Load , Viral Vaccines/genetics
13.
J Pak Med Assoc ; 70(10): 1727-1730, 2020 Oct.
Article in English | MEDLINE | ID: mdl-33159742

ABSTRACT

OBJECTIVE: To investigate the clinical characteristics of early recurrent intussusception after ultrasound-guided saline reduction, and to explore the factors leading to early recurrence. METHODS: The retrospective observational case-control study was conducted at Weifang People's Hospital, Shandong, China, and comprised data from January 2015 to December 2017 related to paediatric intussusception patients aged 0-12 years who underwent ultrasound-guided saline enema reduction. The patients were divided into two recurrent and non-recurrent groups. Clinical characteristics of the patients with early recurrence were analysed. Factors compared between the groups were gender, age, onset season, onset-to-treatment time interval, blood in stool, fever, diarrhoea, abdominal pain and vomiting, weight and pathology. Data was analysed using SPSS 22. RESULTS: Of the 672 subjects, 86(13%) were patient with early recurrence while 586(87%) had no early recurrence and acted as controls. Among the patients, 70(81.4%) were aged 6-36 months. In 52(60.5%) patients, recurrence was once, and in 23(26.7%) twice. There were 141 episodes of intussusception; 24(17%) occurring in <12 hours, 85(60.2%) in 12-24 hours. Also, 5(6%) patients required surgery for reduction. Compared to the controls, the second quarter, heavier body weight and pathology were the factors leading to early recurrence of intussusceptions (p<0.05). CONCLUSIONS: The second quarter, heavier body weight and pathological leading points were found to be factors leading to early recurrent intussusception.


Subject(s)
Intussusception , Saline Solution , Case-Control Studies , Child , Child, Preschool , China , Enema , Humans , Infant , Infant, Newborn , Intussusception/diagnostic imaging , Intussusception/epidemiology , Recurrence , Retrospective Studies , Saline Solution/therapeutic use , Treatment Outcome
14.
J Infect Dis ; 220(1): 105-115, 2019 06 05.
Article in English | MEDLINE | ID: mdl-30778554

ABSTRACT

BACKGROUND: Group B streptococcus (GBS) causes serious diseases in newborn infants, often resulting in lifelong neurologic impairments or death. Prophylactic vaccination of pregnant women prior to delivery could provide comprehensive protection, as early onset and late-onset disease and maternal complications potentially could be addressed. METHODS: Capsular polysaccharide conjugate vaccine GBS6 was designed using surveillance data yielded by whole-genome sequencing of a global collection of recently recovered GBS isolates responsible for invasive neonatal GBS disease. Capsular polysaccharides were isolated, oxidized using sodium periodate, and conjugated to CRM197 by reductive amination in dimethyl sulfoxide. Immune responses in mice and rhesus macaques were measured in a multiplex Luminex immunoglobulin G (IgG) assay and opsonophagocytic activity assays. RESULTS: The optimized conjugates were immunogenic, alone and in combination, in mice and rhesus macaques, inducing IgG antibodies that mediated opsonophagocytic killing. Active immunization of murine dams with GBS6 prior to mating resulted in serotype-specific protection of pups from a lethal challenge with GBS. Protection following passive administration of serotype-specific IgG monoclonal antibodies to dams demonstrated conclusively that anticapsular polysaccharide IgG alone is sufficient for protection. CONCLUSIONS: The findings support the ongoing clinical evaluation of maternal GBS6 vaccination as a potential alternative method to prevent GBS disease in infants.


Subject(s)
Animals, Newborn/immunology , Immunity, Maternally-Acquired/immunology , Polysaccharides, Bacterial/immunology , Streptococcal Infections/immunology , Streptococcal Vaccines/immunology , Streptococcus/immunology , Vaccines, Conjugate/immunology , Animals , Animals, Newborn/microbiology , Antibodies, Bacterial/immunology , Female , Immunization/methods , Immunoglobulin G/immunology , Macaca mulatta/immunology , Macaca mulatta/microbiology , Mice , Serogroup , Streptococcal Infections/microbiology , Vaccination/methods
15.
Immunology ; 156(4): 402-412, 2019 04.
Article in English | MEDLINE | ID: mdl-30575026

ABSTRACT

Hyperactivation of the type 2 immune response is the major mechanism of allergic asthma, in which both group 2 innate lymphoid cells (ILC2s) and type 2 helper T (Th2) cells participate. Myeloid-derived suppressor cells (MDSCs) alleviate asthma by suppressing Th2 cells. However, the potential effects of MDSCs on the biological functions of ILC2s remain largely unknown. Here, we examined the roles of MDSCs (MDSCs) in the modulation of ILC2 function. Our results showed that polymorphonuclear (PMN)-MDSCs, but not monocytic (M-) MDSCs, effectively suppressed the cytokine production of ILC2s both in vitro and in vivo, thereby alleviating airway inflammation. Further analyses showed that cyclo-oxygenase-1 may mediate the suppressive effects of PMN-MDSCs on ILC2 responses. Our findings demonstrated that PMN-MDSCs may serve as a potent therapeutic target for the treatment of ILC2-driven allergic asthma.


Subject(s)
Allergens/immunology , Asthma/immunology , Immunity, Innate/immunology , Inflammation/immunology , Lymphocytes/immunology , Myeloid-Derived Suppressor Cells/immunology , Respiratory System/immunology , Animals , Asthma/pathology , Cell Movement/immunology , Cells, Cultured , Cytokines/biosynthesis , Cytokines/immunology , Disease Models, Animal , Flow Cytometry , Humans , Inflammation/pathology , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Knockout
16.
Biochem Cell Biol ; 97(6): 681-692, 2019 12.
Article in English | MEDLINE | ID: mdl-30817212

ABSTRACT

BACKGROUND: To address the molecular mechanism of the anti-inflammation effects of schisandrin B (Sch B) in atherosclerosis, we examined injured HMEC-1, HBMEC, and HUVEC-12 cells induced by high glucose (HG). METHODS: Western blot was performed to detect the levels of the proteins Hsp27, Noxa, TLR5, p-IκBα, and p-p65 in HG-induced cells, while ELISA was used to analyze the inflammatory cytokines TNF-α, IL-6, MCP-1, and IL-1ß in cells with Hsp27 or Noxa stable expression. RESULTS: Overexpression of Hsp27 upregulated the inflammatory cytokines and the release of IκBα, promoted transportation of p65 into the nucleus, and lastly, affected the inflammation process, while Sch B counteracted the upregulation. In addition, the effect of Noxa overexpression, which is different from Hsp27 overexpression, was consistent with that of Sch B treatment. CONCLUSIONS: Sch B may inhibit the inflammatory cascade and alleviate the injury to HMEC-1, HBMEC, and HUEVC-12 cells caused by HG by regulating the Noxa/Hsp27/NF-κB signaling pathway.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Endothelial Cells/drug effects , Glucose/antagonists & inhibitors , HSP27 Heat-Shock Proteins/antagonists & inhibitors , Lignans/pharmacology , NF-kappa B/antagonists & inhibitors , Polycyclic Compounds/pharmacology , Proto-Oncogene Proteins c-bcl-2/antagonists & inhibitors , Cell Survival/drug effects , Cells, Cultured , Cyclooctanes/pharmacology , Endothelial Cells/metabolism , Endothelial Cells/pathology , Glucose/pharmacology , HSP27 Heat-Shock Proteins/genetics , HSP27 Heat-Shock Proteins/metabolism , Humans , Inflammation/drug therapy , Inflammation/metabolism , Inflammation/pathology , NF-kappa B/genetics , NF-kappa B/metabolism , Proto-Oncogene Proteins c-bcl-2/genetics , Proto-Oncogene Proteins c-bcl-2/metabolism , Signal Transduction/drug effects , Signal Transduction/genetics
17.
Ecotoxicol Environ Saf ; 186: 109822, 2019 Dec 30.
Article in English | MEDLINE | ID: mdl-31634658

ABSTRACT

Nitroaromatic compounds (NACs) are an important type of environmental organic pollutants. However, it is lack of sufficient information relating to their potential adverse effects on human health and the environment due to the limited resources. Thus, using in silico technologies to assess their potential hazardous effects is urgent and promising. In this study, quantitative structure activity relationship (QSAR) and classification models were constructed using a set of NACs based on their mutagenicity against Salmonella typhimurium TA100 strain. For QSAR studies, DRAGON descriptors together with quantum chemistry descriptors were calculated for characterizing the detailed molecular information. Based on genetic algorithm (GA) and multiple linear regression (MLR) analyses, we screened descriptors and developed QSAR models. For classification studies, seven machine learning methods along with six molecular fingerprints were applied to develop qualitative classification models. The goodness of fitting, reliability, robustness and predictive performance of all developed models were measured by rigorous statistical validation criteria, then the best QSAR and classification models were chosen. Moreover, the QSAR models with quantum chemistry descriptors were compared to that without quantum chemistry descriptors and previously reported models. Notably, we also obtained some specific molecular properties or privileged substructures responsible for the high mutagenicity of NACs. Overall, the developed QSAR and classification models can be utilized as potential tools for rapidly predicting the mutagenicity of new or untested NACs for environmental hazard assessment and regulatory purposes, and may provide insights into the in vivo toxicity mechanisms of NACs and related compounds.


Subject(s)
Environmental Pollutants , Hydrocarbons, Aromatic , Mutagens , Nitro Compounds , Algorithms , Computer Simulation , Environmental Pollutants/chemistry , Environmental Pollutants/toxicity , Hydrocarbons, Aromatic/chemistry , Hydrocarbons, Aromatic/toxicity , Machine Learning , Mutagens/chemistry , Mutagens/toxicity , Nitro Compounds/chemistry , Nitro Compounds/toxicity , Quantitative Structure-Activity Relationship , Reproducibility of Results , Salmonella typhimurium/drug effects , Salmonella typhimurium/genetics
18.
Bioconjug Chem ; 29(3): 761-770, 2018 03 21.
Article in English | MEDLINE | ID: mdl-28795800

ABSTRACT

As one of the pathogen-associated molecular patterns (PAMPs), flagellin is recently utilized as a potent adjuvant for many subunit vaccines. In this study, a truncated flagellin (tFL) with deletion of the hypervariable regions was adopted as a carrier-adjuvant by chemical conjugation with a chimeric malaria antigen M.RCAg-1 (M312) via a heterobifunctional polyethylene glycol (PEG) linker. After booster immunization in mice without any extra adjuvants, the M312-PEG-tFL conjugates elicited M312-specific antibody titers 100-1000 times higher than M312 and 10-100 times higher than the physical mixture of M312 and tFL. The elicited specific antibodies could recognize the native parasites, and the immunofluorescence assay (IFA) titer was 2100 for M312-P5k-tFL, which was about 7 times higher than M312. Furthermore, the IFA titers of the conjugates were comparable to the positive control of complete Freund's adjuvant (CFA). Compared to M312, the M312-PEG-tFL conjugates enhanced the proliferation index, lymphocyte activation, and memory T-cell generation. IgG subclasses of sera and cytokines analysis of splenocytes showed that conjugation with tFL could slightly trigger the Th1 polarization, while the antigen alone predominantly induced a Th2-biased immune response. Furthermore, a more-efficient innate immune response was provoked by the M312-PEG-tFL conjugates, as determined by the detection of antigen-specific TNF-α secretion by splenocytes. Our results indicated that tFL mainly retained the function as an agonist of TLR5. Conjugation of antigen to tFL could induce strong humoral and moderate cellular immune responses. Thus, conjugation of antigen to tFL as a potent carrier-adjuvant is an effective strategy for developing a promising protein-based vaccine.


Subject(s)
Adjuvants, Immunologic/therapeutic use , Flagellin/therapeutic use , Immunity, Humoral , Malaria Vaccines/therapeutic use , Malaria, Falciparum/prevention & control , Plasmodium falciparum/immunology , Vaccines, Conjugate/therapeutic use , Adjuvants, Immunologic/chemistry , Adjuvants, Immunologic/pharmacology , Animals , Antibody Formation , Flagellin/chemistry , Flagellin/pharmacology , Immunity, Cellular , Malaria Vaccines/chemistry , Malaria Vaccines/pharmacology , Malaria, Falciparum/immunology , Mice, Inbred BALB C , Vaccines, Conjugate/chemistry , Vaccines, Conjugate/pharmacology
19.
Biomacromolecules ; 19(3): 773-781, 2018 03 12.
Article in English | MEDLINE | ID: mdl-29328653

ABSTRACT

Nanoparticles based on the heavy chain of the human ferritin (HFn) are arousing growing interest in the field of drug delivery due to their exceptional characteristics. However, the unsatisfied plasma half life of HFn substantially limits its application as a delivery platform for antitumor agents. Herein we fused an albumin binding domain (ABD) variant that basically derives from the streptococcal protein G and possesses a long-acting characteristic in serum albumin to the N-terminus of the HFn for the aim of half-life extension. This ABD-HFn construct was highly expressed and fully self-assembled into symmetrical and spherical structure in E. coli bacteria. The purified ABD-HFn showed a similar particle size with wild-type HFn and also exhibited an extremely high binding affinity with human serum albumin. To evaluate the therapeutic potential of this ABD-HFn construct in terms of half-life extension, we encapsulated a model antitumor agent doxorubicin (DOX) into the ABD-HFn. Significantly outstanding loading efficacy of above 60 molecules doxorubicin for each ABD-HFn cage was achieved. The doxorubicin-loaded ABD-HFn nanoparticle was characterized and further compared with the recombinant HFn counterpart. The ABD-HFn/DOX nanoparticle showed dramatically improved stability and comparable cell uptake rate when compared with HFn/DOX counterpart. Pharmacokinetics study in Sprague-Dawley rats showed that ABD-HFn/DOX nanoparticle possessed significantly prolonged plasma half life of ∼17.2 h, exhibiting nearly 19 times longer than that of free doxorubicin and 12 times for HFn/DOX. These optimal results indicated that fusion with ABD will be a promising strategy to extend the half life for protein-based nanoparticles.


Subject(s)
Doxorubicin , Drug Carriers , Ferritins , Recombinant Fusion Proteins , Serum Albumin, Human , A549 Cells , Animals , Doxorubicin/chemistry , Doxorubicin/pharmacokinetics , Doxorubicin/pharmacology , Drug Carriers/chemistry , Drug Carriers/pharmacokinetics , Drug Carriers/pharmacology , Ferritins/chemistry , Ferritins/pharmacokinetics , Ferritins/pharmacology , Half-Life , Humans , Protein Domains , Rats , Rats, Sprague-Dawley , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/pharmacokinetics , Recombinant Fusion Proteins/pharmacology , Serum Albumin, Human/chemistry , Serum Albumin, Human/pharmacokinetics , Serum Albumin, Human/pharmacology
20.
Pediatr Surg Int ; 34(11): 1225-1231, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30151752

ABSTRACT

OBJECTIVE: To investigate the safety and effectiveness of ultrasound-guided saline enema to treat intussusception and to analyze the risk factors affecting short-term recurrence and reduction failure. MATERIALS AND METHODS: We selected patients who had undergone intussusception reduction via ultrasound-guided saline enema from January 2010 to December 2017. The overall success rate, overall pathologic intussusception rate, and pathologic intussusception rate were calculated in each group. All the patients were divided into two groups: the successfully reduced group and the failed reduction group. Then, the successfully reduced patients were divided into two groups: the short-term recurrence group and the short-term non-recurrence group. The differences between each of the two sets of groups were analyzed, and the risk factors affecting short-term recurrence and failure of intussusception were analyzed. RESULTS: During the 8-year study period, a total of 1793 patients with intussusception were treated with ultrasound-guided saline enema reduction in our hospital. Among these patients, 1743 (97.2%) experienced successful reduction, 29 (1.6%) had pathologic intussusception, and 1 experienced perforation. After applying the univariate analysis and logistic regressive multivariate analysis, we found that age above 2 years and the absence of fever were risk factors for the early recurrence of intussusception. Pathologic intussusception was a risk factor for reduction failure. CONCLUSION: The overall success rate of ultrasound-guided saline enemas was 97.2%, and the pathologic intussusception rate was 1.6%. Age above 2 years and the absence of fever were risk factors for short-term recurrence, and pathologic intussusception was a risk factor for the failure of reduction.


Subject(s)
Enema , Intussusception/therapy , Age Factors , Child, Preschool , Female , Humans , Infant , Male , Multivariate Analysis , Recurrence , Retrospective Studies , Risk Factors , Saline Solution , Ultrasonography, Interventional
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