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1.
J Med Chem ; 67(8): 6822-6838, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38588468

RESUMO

Weak antigens represented by MUC1 are poorly immunogenic, which greatly constrains the development of relevant vaccines. Herein, we developed a multifunctional lipidated protein as a carrier, in which the TLR1/2 agonist Pam3CSK4 was conjugated to the N-terminus of MUC1-loaded carrier protein BSA through pyridoxal 5'-phosphate-mediated transamination reaction. The resulting Pam3CSK4-BSA-MUC1 conjugate was subsequently incorporated into liposomes, which biomimics the membrane structure of tumor cells. The results indicated that this lipidated protein carrier significantly enhanced antigen uptake by APCs and obviously augmented the retention of the vaccine at the injection site. Compared with the BSA-MUC1 and BSA-MUC1 + Pam3CSK4 groups, Pam3CSK4-BSA-MUC1 evoked 22- and 11-fold increases in MUC1-specific IgG titers. Importantly, Pam3CSK4-BSA-MUC1 elicited robust cellular immunity and significantly inhibited tumor growth. This is the first time that lipidated protein was constructed to enhance antigen immunogenicity, and this universal carrier platform exhibits promise for utilization in various vaccines, holding the potential for further clinical application.


Assuntos
Lipossomos , Mucina-1 , Animais , Mucina-1/imunologia , Mucina-1/química , Camundongos , Humanos , Lipopeptídeos/química , Lipopeptídeos/imunologia , Lipopeptídeos/farmacologia , Vacinas Anticâncer/imunologia , Vacinas Anticâncer/química , Soroalbumina Bovina/química , Adjuvantes Imunológicos/farmacologia , Adjuvantes Imunológicos/química , Feminino , Camundongos Endogâmicos BALB C , Antígenos/imunologia , Linhagem Celular Tumoral
2.
Dalton Trans ; 53(17): 7303-7314, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38587832

RESUMO

The construction of sulfur-incorporated cluster-based coordination polymers was limited and underexplored due to the lack of efficient synthetic routes. Herein, we report facile mechanochemical ways toward a new series of SFe3(CO)9-based dipyridyl-Cu polymers by three-component reactions of [Et4N]2[SFe3(CO)9] ([Et4N]2[1]) and [Cu(MeCN)4][BF4] with conjugated or conjugation-interrupted dipyridyl ligands, 1,2-bis(4-pyridyl)ethylene (bpee), 1,2-bis(4-pyridyl)ethane (bpea), 4,4'-dipyridyl (dpy), or 1,3-bis(4-pyridyl)propane (bpp), respectively. X-ray analysis showed that bpee-containing 2D polymers demonstrated unique SFe3(CO)9 cluster-armed and cluster-one-armed coordination modes via the hypervalent µ5-S atom. These S-Fe-Cu polymers could undergo flexible structural transformations with the change of cluster bonding modes by grinding with stoichiometric amounts of dipyridyls or 1/[Cu(MeCN)4]+. They exhibited semiconducting behaviors with low energy gaps of 1.55-1.79 eV and good electrical conductivities of 3.26 × 10-8-1.48 × 10-6 S cm-1, tuned by the SFe3(CO)9 cluster bonding modes accompanied by secondary interactions in the solid state. The electron transport efficiency of these polymers was further elucidated by solid-state packing, X-ray photoelectron spectroscopy (XPS), X-ray absorption near-edge spectroscopy (XANES), density of states (DOS), and crystal orbital Hamilton population (COHP) analysis. Finally, the solid-state electrochemistry of these polymers demonstrated redox-active behaviors with cathodically-shifted patterns compared to that of [Et4N]2[1], showing that their efficient electron communication was effectively enhanced by introducing 1 and dipyridyls as hybrid ligands into Cu+-containing networks.

4.
ACS Chem Biol ; 18(4): 915-923, 2023 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-37009726

RESUMO

Modification of antigens to improve their immunogenicity represents a promising direction for the development of protein vaccine. Here, we designed facilely prepared adjuvant-free vaccines in which the N-glycan of SARS-CoV-2 receptor-binding domain (RBD) glycoprotein was oxidized by sodium periodate. This strategy only minimally modifies the glycans and does not interfere with the epitope peptides. The RBD glycoprotein oxidized by high concentrations of periodate (RBDHO) significantly enhanced antigen uptake mediated by scavenger receptors and promoted the activation of antigen-presenting cells. Without any external adjuvant, two doses of RBDHO elicited 324- and 27-fold increases in IgG antibody titers and neutralizing antibody titers, respectively, compared to the unmodified RBD antigen. Meanwhile, the RBDHO vaccine could cross-neutralize all of the SARS-CoV-2 variants of concern. In addition, RBDHO effectively enhanced cellular immune responses. This study provides a new insight for the development of adjuvant-free protein vaccines.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , Adjuvantes Imunológicos , Anticorpos Neutralizantes , COVID-19/prevenção & controle , Vacinas contra COVID-19/química , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/farmacologia , Imunidade , SARS-CoV-2
5.
Neurogastroenterol Motil ; 35(7): e14536, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36780514

RESUMO

BACKGROUND: Irritable bowel syndrome (IBS) is a prevalent gastrointestinal disease characterized by intermittent abdominal pain with altered bowel habits. Due to the condition's chronicity, patients suffer from poor quality of life, while the healthcare burden continues to grow. There is currently no reliable biomarker for the diagnosis of IBS, and the current approach depends on ruling-out organic diseases such as inflammatory bowel disease (IBD) and colorectal cancer by markers of inflammation like fecal calprotectin and C-reactive protein, or invasive procedures like a colonoscopy. Volatile organic compounds (VOCs) are growing in popularity as a biomarker due to its accuracy and ease of use. PURPOSE: This systematic review of Medline and Cochrane's databases aimed to identify VOCs in the diagnosis of IBS. 57% of the studies proved that VOCs could identify IBS patients from healthy controls with AUC ranging from 0.83 to 0.99. Studies that distinguished IBS from IBD patients had slightly higher AUC of 0.87-0.98. Combining VOC into panels allowed the creation of discriminative algorithms. Though current research is limited by areas of heterogeneity in VOC sampling and small sample sizes, our review shows that VOC analysis has the potential to be a noninvasive point-of-care test that differentiates IBS from other organic gastrointestinal diseases.


Assuntos
Gastroenteropatias , Doenças Inflamatórias Intestinais , Síndrome do Intestino Irritável , Compostos Orgânicos Voláteis , Humanos , Síndrome do Intestino Irritável/diagnóstico , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/metabolismo , Qualidade de Vida , Diagnóstico Diferencial , Doenças Inflamatórias Intestinais/diagnóstico , Biomarcadores/metabolismo , Gastroenteropatias/diagnóstico , Fezes/química
6.
Artigo em Inglês | MEDLINE | ID: mdl-36748861

RESUMO

Developing a novel and potent adjuvant with great biocompatibility for immune response augmentation is of great significance to enhance vaccine efficacy. In this work, we prepared a long-term stable, pH-sensitive, and biodegradable Mn3(PO4)2·3H2O nanoparticle (nano-MnP) by simply mixing MnCl2/NaH2PO4/Na2HPO4 solution for the first time and employed it as an immune stimulant in the bivalent COVID-19 protein vaccine comprised of wild-type S1 (S1-WT) and Omicron S1 (S1-Omicron) proteins as antigens to elicit a broad-spectrum immunity. The biological experiments indicated that the nano-MnP could effectively activate antigen-presenting cells through the cGAS-STING pathway. Compared with the conventional Alum-adjuvanted group, the nano-MnP-adjuvanted bivalent vaccine elicited approximately 7- and 8-fold increases in IgG antibody titers and antigen-specific IFN-γ secreting T cells, respectively. Importantly, antisera of the nano-MnP-adjuvanted group could effectively cross-neutralize the SARS-CoV-2 and its five variants of concern (VOCs) including Alpha, Beta, Gamma, Delta, and Omicron, demonstrating that this bivalent vaccine based on S1-WT and S1-Omicron proteins is an effective vaccine design strategy to induce broad-spectrum immune responses. Collectively, this nano-MnP material may provide a novel and efficient adjuvant platform for various prophylactic and therapeutic vaccines and provide insights for the development of the next-generation manganese adjuvant.

7.
J Med Chem ; 66(2): 1467-1483, 2023 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-36625758

RESUMO

Exploring potent adjuvants and new vaccine strategies is crucial for the development of protein vaccines. In this work, we synthesized a new TLR4 agonist, structurally simplified lipid A analogue GAP112, as a potent built-in adjuvant to improve the immunogenicity of SARS-CoV-2 spike RBD protein. The new TLR4 agonist GAP112 was site-selectively conjugated on the N-terminus of RBD to construct an adjuvant-protein conjugate vaccine in a liposomal formulation. It is the first time that a TLR4 agonist is site-specifically and quantitatively conjugated to a protein antigen. Compared with an unconjugated mixture of GAP112/RBD, a two-dose immunization of the GAP112-RBD conjugate vaccine strongly activated innate immune cells, elicited a 223-fold increase in RBD-specific antibodies, and markedly enhanced T-cell responses. Antibodies induced by GAP112-RBD also effectively cross-neutralized SARS-CoV-2 variants (Delta/B.1.617.2 and Omicron/B.1.1.529). This conjugate strategy provides an effective method to greatly enhance the immunogenicity of antigen in protein vaccines against SARS-CoV-2 and other diseases.


Assuntos
COVID-19 , Lipossomos , Humanos , Adjuvantes Imunológicos/farmacologia , Adjuvantes Farmacêuticos , Anticorpos , COVID-19/prevenção & controle , Vacinas contra COVID-19/farmacologia , SARS-CoV-2 , Receptor 4 Toll-Like , Vacinas Conjugadas
8.
J Control Release ; 355: 238-247, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36716860

RESUMO

Self-adjuvanting protein vaccines have been proved to be highly immunogenic with efficient codelivery of adjuvant and antigen. Current protein vaccines with built-in adjuvants are all modified at the peptide backbone of antigen protein, which could not achieve minor epitope interference and adjuvant multivalency at the same time. Herein, we developed a new conjugate strategy to construct effective adjuvant-protein vaccine with adjuvant cluster effect and minimal epitope interference. The toll-like receptor 7 agonist (TLR7a) is covalently conjugated on the terminal sialoglycans of SARS-CoV-2-S1 protein, leading to intracellular release of the small-molecule stimulators with greatly reduced risks of systemic toxicity. The resulting TLR7a-S1 conjugate elicited strong activation of immune cells in vitro, and potent antibody and cellular responses with a significantly enhanced Th1-bias in vivo. TLR7a-S1-induced antibody also effectively cross-neutralized all variants of concern. This sialoglycoconjugation approach to construct protein conjugate vaccines will have more applications to combat SARS-CoV-2 and other diseases.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , COVID-19/prevenção & controle , SARS-CoV-2 , Adjuvantes Imunológicos , Antígenos , Adjuvantes Farmacêuticos , Epitopos
9.
Pest Manag Sci ; 79(5): 1963-1976, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36680499

RESUMO

BACKGROUND: A key challenge for unmanned aerial vehicle (UAV) spraying sometimes used in tea plantations is the downwash flow structure there stronger than in crops. In addition, the UAV spray is affected by the relationship between the nozzle design and the pesticide. However, there is little current research on this aspect. As a preliminary step this study focuses on the most appropriate pesticide for a designated nozzle in a six-rotor UAV according to the nozzle-pesticide relationship using a three-dimensional computational fluid dynamics model. This model considers the downwash flow structure effect and nozzle spray performance in hover. Nozzle FVP110-02, widely used in six-rotor UAVs, is used as a representative nozzle and bifenthrin and tea saponin water, commonly used in tea plantations, are used as the pesticides. RESULTS: The downwash flow structure of the six-rotor UAV in hover was conveniently controlled by the flight height and rotational speed, thereby causing the turbulence to be more stable. For nozzle FVP110-02, bifenthrin was more appropriate than tea saponin water at the same concentration, whilst bifenthrin and tea saponin water at a concentration of 1:1000 showed the best performance under identical working conditions. CONCLUSION: The numerical model developed here was shown to be effective for investigating the relationship between nozzle and pesticide. Our findings will help to not only improve UAV spraying for tea cultivation but also provide guidelines for pesticide selection in crops. Further work will address the comparison of the rigorous qualification of the numerical simulations with the measurements by the field test. © 2023 Society of Chemical Industry.


Assuntos
Praguicidas , Praguicidas/análise , Dispositivos Aéreos não Tripulados , Produtos Agrícolas , Chá
10.
Singapore Med J ; 64(5): 313-318, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-35706407

RESUMO

Introduction: There has been a global decrease in operative vaginal deliveries, with a marked shift towards the vacuum extractor. However, little is known about the trends in operative vaginal delivery in Singapore. Methods: A retrospective study was conducted on all operative vaginal deliveries performed from 2012 to 2017 at Singapore General Hospital (SGH). Maternal outcomes in terms of postpartum haemorrhage and obstetric anal sphincter injuries were compared between forceps- and vacuum-assisted deliveries. Neonatal outcomes in terms of neonatal intensive care unit (NICU) admission and clinically significant neonatal events were compared. The instrument preference of obstetricians was analysed. Results: A total of 906 consecutive operative vaginal deliveries were included in the study, comprising 461 forceps- and 445 vacuum-assisted deliveries. The rate of operative vaginal delivery was maintained at approximately 10% from 2012 to 2017. Neonatal cephalohematomas were more common after vacuum-assisted deliveries. Other maternal and neonatal outcomes did not differ significantly between the two groups. Clinically significant neonatal events were mostly due to shoulder dystocia, whereas all cases of NICU admissions were not directly related to the mode of delivery. Obstetricians' choice of instrument appeared to reflect personal preference and was not affected by the year of graduation. Conclusion: The rates of neonatal and maternal morbidity were low at SGH. Overall instrument use of forceps and vacuum was balanced, and proficiency in both was demonstrated by all operators. Operative vaginal delivery remains an essential skill in facilitating safe vaginal delivery, which should be maintained to keep Caesarean section rates in check.


Assuntos
Cesárea , Vácuo-Extração , Recém-Nascido , Gravidez , Humanos , Feminino , Estudos Retrospectivos , Vácuo-Extração/efeitos adversos , Hospitais Gerais , Forceps Obstétrico/efeitos adversos , Parto Obstétrico
11.
Food Chem ; 403: 134377, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36182848

RESUMO

This study developed a simple, rapid, stable, and reliable technique for acrylamide (AAm) detection through surface-enhanced Raman scattering (SERS) on an AgNPs substrate with an aggregating agent. Specifically, the agglomeration effects of five types of salt solutions (NaCl, KCl, MgCl2, Na2SO4, and MgSO4) were investigated at different concentrations and optimized using an orthogonal experiment. The optimal amounts of the aggregating agent, analytes, and AgNPs were 4, 4, and 12 µL, respectively. A linear relationship (peak area I1449 = 7.4197x + 5984.8, R2 = 0.9971) between the characteristic peak area and AAm concentration was established in the range of 10 to 500 µg/L, and the LOD was 2.5 µg/L. The recoveries and relative standard deviations in the analysis of potato chips samples were 94.67 %-117.50 % and 8.43 %-12.29 %, respectively. The results of the proposed method were consistent with those obtained by LC-MS/MS method. This study demonstrated that SERS has excellent potential for application in the qualitative and quantitative analyses of AAm in fried foods.


Assuntos
Acrilamida , Nanopartículas Metálicas , Acrilamida/análise , Análise Espectral Raman/métodos , Cromatografia Líquida , Espectrometria de Massas em Tandem , Contaminação de Alimentos/análise , Nanopartículas Metálicas/análise
12.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-978515

RESUMO

Objective To investigate the mechanisms underlying allergic conjunctivitis caused by conjunctival epithelial cell damage, neutrophil migration and neutrophil extracellular traps (NETs) formation induced by crude extracts of Dermatophagoides farinae mite (CDM). Methods Human conjunctival epithelial cells were stimulated with 500, 1 000, 2 000, 4 000 ng/mL, and the expression levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ) and IL-8 were detected using quantitative real-time PCR (qPCR) assay and enzyme-linked immunosorbent assay (ELISA). The culture supernatant of human conjunctival epithelial cells was collected and co-cultured with neutrophils. Neutrophil migration was measured using Transwell migration assay, and the expression of NETs markers myeloperoxidase (MPO) and citrullinated histone H3 (CitH3) was quantified using immunofluorescence staining. Neutrophils were stimulated with phorbol 12-myristate 13-acetate (PMA), and then NETs were collected for treatment of human conjunctival epithelial cells. Cell apoptosis was detected using flow cytometry, and the levels of IL-6, TNF-α, IFN-γ and IL-8 were measured in the cell culture supernatant using ELISA. Results Treatment with CDM at concentrations of 2 000 ng/mL and 4 000 ng/mL up-regulated IL-6, TNF-α, IFN-γ and IL-8 expression in human conjunctival epithelial cells. Following treatment with CDM at concentrations of 2 000 ng/mL and 4 000 ng/mL, the culture supernatant of human conjunctival epithelial cells promoted neutrophil migration and induced increases in the staining intensity of MPO and CitH3. In addition, increased NETs triggered the apoptosis of human conjunctival epithelial cells and IL-6, TNF-α, IFN-γ and IL-8 secretion in the culture supernatant of human conjunctival epithelial cells. Conclusions CDM induces human conjunctival epithelial cell damages, thereby promoting neutrophil migration and NETs formation, while the release of NETs further aggravates human conjunctival epithelial cell damages.

13.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-986137

RESUMO

OBJECTIVE@#To investigate the mechanisms underlying allergic conjunctivitis caused by conjunctival epithelial cell damage, neutrophil migration and neutrophil extracellular traps (NETs) formation induced by crude extracts of Dermatophagoides farinae mite (CDM).@*METHODS@#Human conjunctival epithelial cells were stimulated with 500, 1 000, 2 000, 4 000 ng/mL, and the expression levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ) and IL-8 were detected using quantitative real-time PCR (qPCR) assay and enzyme-linked immunosorbent assay (ELISA). The culture supernatant of human conjunctival epithelial cells was collected and co-cultured with neutrophils. Neutrophil migration was measured using Transwell migration assay, and the expression of NETs markers myeloperoxidase (MPO) and citrullinated histone H3 (CitH3) was quantified using immunofluorescence staining. Neutrophils were stimulated with phorbol 12-myristate 13-acetate (PMA), and then NETs were collected for treatment of human conjunctival epithelial cells. Cell apoptosis was detected using flow cytometry, and the levels of IL-6, TNF-α, IFN-γ and IL-8 were measured in the cell culture supernatant using ELISA.@*RESULTS@#Treatment with CDM at concentrations of 2 000 ng/mL and 4 000 ng/mL up-regulated IL-6, TNF-α, IFN-γ and IL-8 expression in human conjunctival epithelial cells. Following treatment with CDM at concentrations of 2 000 ng/mL and 4 000 ng/mL, the culture supernatant of human conjunctival epithelial cells promoted neutrophil migration and induced increases in the staining intensity of MPO and CitH3. In addition, increased NETs triggered the apoptosis of human conjunctival epithelial cells and IL-6, TNF-α, IFN-γ and IL-8 secretion in the culture supernatant of human conjunctival epithelial cells.@*CONCLUSIONS@#CDM induces human conjunctival epithelial cell damages, thereby promoting neutrophil migration and NETs formation, while the release of NETs further aggravates human conjunctival epithelial cell damages.


Assuntos
Animais , Humanos , Armadilhas Extracelulares , Neutrófilos , Interleucina-8/metabolismo , Dermatophagoides farinae , Interleucina-6/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Células Epiteliais , Interferon gama/metabolismo , Acetato de Tetradecanoilforbol/farmacologia
14.
Singapore medical journal ; : 313-318, 2023.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-984216

RESUMO

INTRODUCTION@#There has been a global decrease in operative vaginal deliveries, with a marked shift towards the vacuum extractor. However, little is known about the trends in operative vaginal delivery in Singapore.@*METHODS@#A retrospective study was conducted on all operative vaginal deliveries performed from 2012 to 2017 at Singapore General Hospital (SGH). Maternal outcomes in terms of postpartum haemorrhage and obstetric anal sphincter injuries were compared between forceps- and vacuum-assisted deliveries. Neonatal outcomes in terms of neonatal intensive care unit (NICU) admission and clinically significant neonatal events were compared. The instrument preference of obstetricians was analysed.@*RESULTS@#A total of 906 consecutive operative vaginal deliveries were included in the study, comprising 461 forceps- and 445 vacuum-assisted deliveries. The rate of operative vaginal delivery was maintained at approximately 10% from 2012 to 2017. Neonatal cephalohematomas were more common after vacuum-assisted deliveries. Other maternal and neonatal outcomes did not differ significantly between the two groups. Clinically significant neonatal events were mostly due to shoulder dystocia, whereas all cases of NICU admissions were not directly related to the mode of delivery. Obstetricians' choice of instrument appeared to reflect personal preference and was not affected by the year of graduation.@*CONCLUSION@#The rates of neonatal and maternal morbidity were low at SGH. Overall instrument use of forceps and vacuum was balanced, and proficiency in both was demonstrated by all operators. Operative vaginal delivery remains an essential skill in facilitating safe vaginal delivery, which should be maintained to keep Caesarean section rates in check.


Assuntos
Recém-Nascido , Gravidez , Humanos , Feminino , Cesárea , Estudos Retrospectivos , Vácuo-Extração/efeitos adversos , Hospitais Gerais , Forceps Obstétrico/efeitos adversos , Parto Obstétrico
15.
Inorg Chem ; 61(50): 20433-20444, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36475687

RESUMO

The transition metal-stabilized heavy main group radicals are extremely scarce due to their highly reactive natures, making them difficult to be isolated and identified. We report here a rare class of the Se radical-containing manganese carbonyl anionic cluster, [(µ-Se)(µ3-Se2)2Mn3(CO)9]•2- (1), which was successfully obtained from the one-pot reaction of Se powder and Mn2(CO)10 in concentrated KOH/MeOH/MeCN solutions at 90 °C. Dianion 1 and its dimeric cluster, [(µ4-Se2){(µ3-Se2)2Mn3(CO)9}2]4- [(1)2], could undergo the reversible Se-Se bond breakage or reformation by the thermal cracking of (1)2 or self-dimerization of 1, showing the µ-Se•- radical character of 1. Complex 1 could react with (2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO) to form the Se radical-captured complex [(µ-Se(TEMPO)) (µ3-Se2)2Mn3(CO)9]2- (1-TEMPO) or could react with alkylene bromides (CH2)nBr2 (n = 1, 2) to give the Mn4-based oxidative coupling products, [(µ4-Se2)(µ-Se2LSe)2Mn4(CO)12]2- (L = CH2, 2-CH2; Se, 2-Se). In addition, dianion 1 and its aggregated derivatives (1)2, 1-TEMPO, 2-CH2, and 2-Se exhibited unusual paramagnetic properties with the spin-state switching from S = 1 (Mn) + 1/2 (Se) to S = 1 (Mn), in which their magnetic centers were proved to be mixed-valent Mn atoms and the µ-Se•- radical, as evidenced by Evans method, superconducting quantum interference device, X-ray photoelectron spectra, electron paramagnetic resonance, and density functional theory calculations. Importantly, these clusters showed semiconducting behaviors with low and tunable energy gaps (1.50-2.01 eV) and varied electrical conductivities (2.52 × 10-8-4.58 × 10-9 S/cm), where efficient electron transports mainly arose from C-H(phenyl)···O(carbonyl) interactions within the solid-state frameworks.

16.
World J Clin Cases ; 10(23): 8360-8366, 2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-36159534

RESUMO

BACKGROUND: Relapsing polychondritis is a rare multisystem autoimmune disease that mainly involves systemic cartilage and proteoglycan-rich tissues. If the larynx and trachea are involved, the patient's condition deteriorates rapidly. When relapsing polychondritis becomes more advanced, the airways collapse and treatment is difficult, rendering a poor prognosis. Therefore, the diagnosis method, treatment strategy and prognosis of relapsing polychondritis with larynx and trachea involvement need to be elucidated to improve clinicians' awareness of the disease. CASE SUMMARY: A man and a woman were admitted because of breathlessness. Relapsing polychondritis was diagnosed after a series of accessory examinations. They were both treated with glucocorticoids and immunosuppressants, and underwent tracheotomy as their breathing difficulties could not be relieved by the medication. CONCLUSION: The two cases highlight the importance of the timely diagnosis, full evaluation and initiating individualized treatment of relapsing polychondritis with larynx and trachea involvement. Laryngoscopy, bronchoscopy and pathological examination are helpful in diagnosis of this disease.

17.
Aging Dis ; 13(4): 1252-1266, 2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35855330

RESUMO

Short-chain fatty acids (SCFAs) are important metabolites derived from the gut microbiota through fermentation of dietary fiber. SCFAs participate a number of physiological and pathological processes in the human body, such as host metabolism, immune regulation, appetite regulation. Recent studies on gut-brain interaction have shown that SCFAs are important mediators of gut-brain interactions and are involved in the occurrence and development of many neurodegenerative diseases, including Alzheimer's disease. This review summarizes the current research on the potential roles and mechanisms of SCFAs in AD. First, we introduce the metabolic distribution, specific receptors and signaling pathways of SCFAs in human body. The concentration levels of SCFAs in AD patient/animal models are then summarized. In addition, we illustrate the effects and mechanisms of SCFAs on the cognitive level, pathological features (Aß and tau) and neuroinflammation in AD. Finally, we analyze the translational value of SCFAs as potential therapeutic targets for the treatment of AD.

18.
Food Res Int ; 158: 111512, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35840220

RESUMO

Geographic-label is a remarkable feature for Chinese tea products. In this study, the UHPLC-Q/TOF-MS-based metabolomics approach coupled with chemometrics was used to determine the five narrow-geographic origins of Keemun black tea. Thirty-nine differentiated compounds (VIP > 1) were identified, of which eight were quantified. Chemometric analysis revealed that the linear discriminant analysis (LDA) classification accuracy model is 91.7%, with 84.7% cross-validation accuracy. Three machine learning algorithms, namely feedforward neural network (FNN), random forest (RF) and support vector machine (SVM), were introduced to improve the recognition of narrow-geographic origins, the performances of the model were evaluated by confusion matrix, receiver operating characteristic curve (ROC) and area under the curve (AUC). The recognition of RF, SVM and FNN for Keemun black tea from five narrow-geographic origins were 87.5%, 94.44%, and 100%, respectively. Importantly, FNN exhibited an excellent classification effect with 100% accuracy. The results indicate that metabolomics fingerprints coupled with chemometrics can be used to authenticate the narrow-geographic origins of Keemun black teas.


Assuntos
Camellia sinensis , Chá , Algoritmos , Cromatografia Líquida de Alta Pressão , Aprendizado de Máquina , Metabolômica
19.
ACS Infect Dis ; 8(7): 1367-1375, 2022 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-35748575

RESUMO

With the global pandemic of the new coronavirus disease (COVID-19), a safe, effective, and affordable mass-produced vaccine remains the current focus of research. Herein, we designed an adjuvant-protein conjugate vaccine candidate, in which the TLR7 agonist (TLR7a) was conjugated to S1 subunit of SARS-CoV-2 spike protein, and systematically compared the effect of different numbers of built-in TLR7a on the immune activity for the first time. As the number of built-in TLR7a increased, a bell-shaped reaction was observed in three TLR7a-S1 conjugates, with TLR7a(10)-S1 (with around 10 built-in adjuvant molecules on one S1 protein) eliciting a more potent immune response than TLR7a(2)-S1 and TLR7a(18)-S1. This adjuvant-protein conjugate strategy allows the built-in adjuvant to provide cluster effects and prevents systemic toxicity and facilitates the co-delivery of adjuvant and antigen. Vaccination of mice with TLR7a(10)-S1 triggered a potent humoral and cellular immunity and a balanced Th1/Th2 immune response. Meanwhile, the vaccine induces effective neutralizing antibodies against SARS-CoV-2 and all variants of concern (B.1.1.7/alpha, B.1.351/beta, P.1/gamma, B.1.617.2/delta, and B.1.1.529/omicron). It is expected that the adjuvant-protein conjugate strategy has great potential to construct a potent recombinant protein vaccine candidate against various types of diseases.


Assuntos
COVID-19 , SARS-CoV-2 , Adjuvantes Imunológicos/farmacologia , Adjuvantes Farmacêuticos , Animais , COVID-19/prevenção & controle , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Glicoproteína da Espícula de Coronavírus , Receptor 7 Toll-Like , Vacinas Conjugadas
20.
Front Immunol ; 13: 857779, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35371101

RESUMO

The tumor-associated antigen mucin 1 (MUC1) is an attractive target of antitumor vaccine, but its weak immunogenicity is a big challenge for the development of vaccine. In order to enhance immune responses against MUC1, herein, we conjugated small molecular toll-like receptor 7 agonist (TLR7a) to carrier protein BSA via MUC1 glycopeptide to form a three-component conjugate (BSA-MUC1-TLR7a). Furthermore, we combined the three-component conjugate with Alum adjuvant to explore their synergistic effects. The immunological studies indicated that Alum adjuvant and built-in TLR7a synergistically enhanced anti-MUC1 antibody responses and showed Th1-biased immune responses. Meanwhile, antibodies elicited by the vaccine candidate effectively recognized tumor cells and induced complement-dependent cytotoxicity. In addition, Alum adjuvant and built-in TLR7a synergistically enhanced MUC1 glycopeptide-specific memory CD8+ T-cell immune responses. More importantly, the vaccine with the binary adjuvant can significantly inhibit tumor growth and prolong the survival time of mice in the tumor challenge experiment. This novel vaccine construct provides an effective strategy to develop antitumor vaccines.


Assuntos
Vacinas Anticâncer , Neoplasias , Adjuvantes Imunológicos/química , Adjuvantes Imunológicos/farmacologia , Compostos de Alúmen , Hidróxido de Alumínio , Animais , Glicopeptídeos , Imunidade , Camundongos , Mucina-1 , Neoplasias/terapia , Receptor 7 Toll-Like/agonistas
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